Polycystography in the evaluation of carcinoma of the urinary bladder. Polycystography is a safe, simple, useful, radiological procedure to assess the degree of infiltration of bladder tumors. It broadly classifies bladder tumors into two groups: infiltrating and noninfiltrating. This information is important to plan the treatment. In 96% of the cases, the radiological findings correlated well with other methods of assessing the degree of infiltration. The standard technic, modifications, advantages and disadvantages of this procedure are discussed.


Treatment of lithiasis by the forced injection of liquid and ureteral catheterization by the translumbar route. We have used translumbar intrapelvic injection of liquid and intraureteral sliding of a catheter to push ureteral calculi and obtain their elimination through the bladder in 32 patients. We have described the technic and the results obtained. We had more success with the intraureteral catheter technic. No complications were observed in our cases. Ureteral physiology in relation to the favorable results obtained is discussed.


Effect of cataract on intraocular pressure. Cases of immature and mature cataract were selected to study normal values in relation to hypermature cataract. We observed that cases of hypermature cataract had a high intraocular tension which was associated with a high protein level and increase in the number of macrophages in the aqueous. We concluded that a phacolytic mechanism is responsible for a secondary rise of intraocular tension in cases of hypermature cataract.


Candida sepsis successfully treated by parenteral administration of 5-fluorocytosine. Candida sepsis has become one of the most common and dangerous forms of hospital acquired infection. The recommended drug for parenteral treatment of Candida sepsis is amphotericin B, however, its toxic effects preclude its usage in many patients, particularly in the presence of renal failure. A less toxic antifungal agent is 5-fluorocytosine. A patient with Candida albicans sepsis was treated successfully with 5-fluorocytosine by intravenous administration. The fungal infection developed during the course of acute renal failure, repeated surgical intervention, intravenous hyperalimentation, gastrointestinal bleeding and five months of antibiotic therapy. The clinical symptoms receded rapidly and cultures became sterile after one week of intravenous treatment. The predisposing factors, difficulties in prevention and diagnosis of fungal infection are discussed.


Solid tumors of the liver. Diagnostic and therapeutic problems. The diagnostic and therapeutic problems involved in 29 cases of isolated hepatic tumors have been presented. In nine cases the hepatoma was discovered during emergency treatment for complications. Selective arteriography was the most accurate method of establishing the etiologic diagnosis. Suprahepatic phlebography indicated the possibilities for surgical treatment. These possibilities are not influenced by the volume of the tumor, but are closely dependent on damage to the suprahepatic vascular system. Effective surgery was performed in 22 cases, of which 14 were excisions.


Malignant tumors of the thyroid.

Malignant tumors of the thyroid. Carcinoma of the thyroid gland is not common. The majority of lesions in this series were differentiated in type. The treatment of choice is almost total thyroidectomy supplemented by I131 in some cases. L-thyroxine was prescribed routinely for all patients postoperatively for replacement and depression treatment. The immediate postoperative mortality was about 1% and prognosis is relatively good. Undifferentiated thyroid carcinomas are fast growing and very lethal and unfortunately no method of treatment is effective. Only four patients in this group survived more than a year.


Perineovulvovaginal preoperative preparation in minor gynecological surgery. Fifty consecutive patients underwent minor elective gynecologic surgery. Most of them were from the low socioeconomic class. Twenty-five patients had their pubic, vulval and perineal hair shaved as part of the preoperative preparation. All patients underwent the same routine perineal, vulval and vaginal swabbing in the operating room. All patients were then examined for postoperative complications. Only two women (who were shaved) complained of mild lower abdominal pain 48 hours after operation, but neither had any clinical evidence of genital or urinary infection. Their symptoms disappeared with the use of analgesics. Even in developing countries where patients with poor personal hygiene are common, preoperative vulval, pubic and perineal hair shaving prior to minor gynecologic surgery is unnecessary. We suggest that this procedure should be discontinued.


Incidence and evolution of moles and the relationship to malignant melanoma in eastern India. Malignant melanoma is rather uncommon in India. Pigmented moles are also less common than among Caucasians. The fewer number of moles probably is one factor responsible for the relative rarity of malignant melanomas in this area.


Hormonal therapy and cholelithiasis.

Hormonal therapy and cholelithiasis. This report is to alert the abdominal surgeon to a new factor responsible for a rising incidence of cholelithiasis in the younger woman. The cause of cholelithiasis has been explained on the basis of biochemical changes with mechanical obstruction. The role of estrogen-progesterone elevation in pregnancy with associated hypercholesteremia is well-known. Little known are reports (more common in non-American literature) that female hormones effect a sluggishness of gallbladder function. Thus, a chemical change with a functional type of obstruction in the biliary tree predisposes toward cholelithiasis. A survey of 1346 cholecystic operations from 1969 through 1973 showed the expected greater incidence in women. Women under 40 years of age who received hormonal medication were younger when operated upon than a comparable group not receiving hormonal therapy. The incidence of gallbladder disease in young women using hormonal therapy should be expected to increase in the coming years. Cholelithiasis should be suspected in the young female taking birth control medication. X-ray study is indicated and early surgery is desirable to prevent morbidity, mortality and the complications of cholecystic disease.


Pattern of acute head injuries in Ibadan. A series of 525 patients with head injuries was analyzed. Males and young people, especially children under 10, predominated. More injuries were sustained on Sunday than any other day, and were mostly caused by road traffic accidents and domestic accidents. Limb injuries were the most common associated wounds. The more severely disturbed the level of consciousness on admission, the worse was the prognosis.


Surgical management of pyogenic pericarditis. Sixteen cases of acute pyogenic pericarditis have been reviewed. Uncontrollable septic course, episodes of cardiac tamponade and failure of the nonsurgical regimen were the main indications for surgery. Medical management is often ineffective because of the relentless septic course, presence of thick, viscid pus and granulation tissue, and loculation. Even if it is effective, it may not halt the progression to constriction. We treated these cases by emergency pericardiectomy. The results were gratifying, the risk of cardiac tamponade was eliminated and termination of the septic course was dramatic. The mortality rate was within acceptable limits. All the survivors have remained asymptomatic.


Triple isotope scintiphotography for differentiating between renal cysts and renal tumors. As a routine diagnostic approach to patients who present hematuria or abnormal findings in X-ray films such as intravenous pyelograms, the cases are submitted to serial scintiphotography every two minutes after the intravenous administration of 250 muCi of 131I-Hippuran and to renography with PHO/GAMMA Scintillation Camera (Nuclear-Chicago). When scintiphotography with 131I-Hippuran reveals filling defect in the kidney region, scintiphotography with 150 muCi of 203Hg-chlormerodrin and renal blood flow scintiphotography after antecubital intravenous injection of 10 mCi of 99mTc are carried out. The present report concerns 8 cases of renal tumor and 5 cases of renal cyst confirmed by X-ray examination and surgical operation. The scintiphotography revealed decreased uptake of 131I-Hippuran and 203Hg-chlormerodrin in both tumor and cyst sites, exhibiting round or band-shaped filling defects. On the other hand, renal blood flow scintiphotography with 99mTc demonstrated the cyst as a filling defect but failed to visualize most of tumors. Accordingly, these techniques are available for differential diagnosis of the two lesions.


Four-channel radioisotope renography (complex investigations). An attempt has been made at a fuller utilization of the information content of 131I-Hippurate in four-channel renography, recording the activities over the kidneys, heart and bladder. The four-channel system was supplemented with a digital scaler, which enabled also the volume of residual urine to be determined after renography. In functional disorder of the upper outflow tract, the examinations were performed in both supine and sitting positions. The expanded procedure has rendered the familiar method of renography more valuable and has often given essential diagnostic help when used in combination with other clinical data.


Renal colic and associated pyelorenal reflux as a cause of some diseases. Renal colic always involves pelvic hypertension and severe urodynamic disturbances which result in fornical reflux, urine leakage to renal interstitial tissues, to tissues of the renal sinus, and sometimes to the retroperitoneal space. If the urinary tract is infected, renal colic may lead to acute pyelonephritis and generalized infection, as well as to bacteriemic shock. Of great importance in the origin of retroperitoneal fibrosis are fornical refluxes. Since renal colic is the most frequent cause of pyelorenal reflux, patients with renal colic should be promptly given appropriate treatment aimed at eliminating or at least lowering pelvic hypertension.


The angiographic appearance of renal angiomyolipoma and problems of its preoperative diagnosis. The radiodiagnostic difficulties of renal hamartoma (renal angiomyolipoma) have been discussed in connection with the authors' two cases. In the first case a unifocal cystic renal angiomyolipoma without tuberous sclerosis caused retroperitoneal haematoma and acute symptoms. In the second case a preoperative tentative diagnosis of angiomyolipoma was made, however, the Pringle-type dermal lesions were only observed 6 months after surgery on control examination. The authors state that the radiographic functional findings vary depending on the tissue structure of the tumour. Differential diagnosis of cystic angiomyolipoma containing little fatty and angiomatous tissue is impossible, whereas for the hypervascular variant a tentative diagnosis can be established even in the case of unifocal hamartoma.


Results of operative treatment of vesicoureteral reflux by the Leadbetter-Politano method in children. In this work the results of vesicoureteroplasty performed by the Leadbetter-Politano method in 77 children are presented. The indications for a vesicoureteroplasty procedure are outlined. Bad results are analysed and the causes of failure and possibilities of preventing them are considered. Probable causes of vesicoureteral reflux on the side opposite to the operated one, and the influence of coexisting congenital anomalies of urinary tract upon operative results are discussed.


Congenital stricture of male urethra.

Congenital stricture of male urethra. Seven cases of anterior urethral stricture were studied. The diagnosis was made by exclusion of the inflammatory and traumatic causes. In three cases the stricture was located in the bulbar and in four cases in the penile urethra. The results obtained were good, with a follow-up of 5 to 50 months. Considerations are made about embryogenic, diagnostic, clinical picture and treatment. The verification of extensive lesions of the urethra determined the use of more complex surgical techniques of Johansen's urethroplasty devised for the treatment of this kind of pathology.


Piromidic acid and its ethylic ester: absorption, distribution, excretion. The absorption, distribution and excretion of piromidic acid and its ethyl ester were investigated in the rat. When administered orally the ethyl ester was well absorbed and subsequently hydrolysed, giving much higher blood and tissue concentration than a corresponding dose of the parent compound. The antimicrobial activity of urine and bile samples was also investigated.


Appendectomies in patients with nephritis. A retrospective study of 150 records of patients attending a renal clinic revealed a high (10 per cent) incidence of history of appendectomy. The possibility that an acute exacerbation of pyelonephritis, especially on the right side, might be misdiagnosed in some cases as appendicitis is discussed. Acute renal failure following unnecessary appendectomy in a patient with previously unrecognized and asymptomatic chronic renal disease may occur if this possibility is not borne in mind before operating on an atypical case of appendicitis.


Use of absorbable material for the closure of experimental longitudinal nephrotomy. Large nephrotomy incisions made in 15 dogs were closed by sewing up the cavity system with stitches of 5/0 catgut and by sealing the renal parenchyma with tissue adhesive being pinpointed at the opened vessels. The incision was covered with a preparation of oxidized cellulose which was then likewise impregnated with tissue adhesive. This technique was found rapid and convenient and provided for adequate haemostasis. Its essential advantage lies in eliminating the deep through-and-through sutures involving a major loss of functioning renal parenchyma. All substances used were absorbed in due time.


Haemorrhagic pericarditis and cardiac tamponade during chronic haemodialysis. Three cases of uraemic haemorrhagic pericarditis observed during haemodialysis treatment are described. The condition is explained with uraemic toxicosis, cyclic heparinaemia resulting from dialysis, deficient thrombocyte function, and decreased capillary resistance. The clinical appearance of haemorrhagic pericarditis was not typical in any of the cases. Two patients died, while in one patient partial pericardiectomy was performed with success.


Method of choice for urinary diversion in surgical treatment of bladder carcinoma. Evidence is presented concerning 94 patients with malignancy of bladder in whom diversion of urine was performed after cystectomy for exclusion of the bladder. There were 80 men and 14 women, ages ranging from 30 to 81 years. In 35 of these 94 cases ureterosigmoidoanastomosis, in 38 cases ureterocutaneostomy, in 15 Portilla's operation, in 2 Bricker's method and in 4 nephro-pyelostomy were performed. For the prevention of bleeding cystectomy was preceded by bilateral ligation of the internal iliac artery in 14 cases. Continuous postoperative follow-up of the patients (from a few months to 14 years) and analysis of the early and late results allow to regard the combined technique of Coffey II-Nesbit-Goodwin as the method of choice having the slightest risk of peritonitis, intestinoureteral reflux and other complications inherent in other procedures. Of the existing methods of ureterocutaneostomy the authors have chosen Le Dentu's method with some modifications. They consider ureterostomy to be the simplest and quickest method owing to the higher location of ureterostoma. Portilla's method is no longer used because of its unfavourable long-term results. Of 94 patients with cancer of the bladder, who had been subjected to different methods of urinary diversion in the years 1954-1974, 16 have survived up till now. There are 10 survivors after ureterosigmoidoanastomosis, 5 after ureterocutaneostomy and 1 after Bricker's operation.


Vascular changes in the urinary bladder wall after irradiation (an experimental study in rabbits with angiography and scanning electron microscopy of vascular casts). Seven adult rabbits were used to study radiation-induced vascular changes in the urinary bladder by angiography and scanning electron microscopy of vascular casts. The angiographic studies, in which a magnification techniques was used, revealed a state of hypervascularization in the irradiated area of the bladder. With the angiographic method, however, it was not possible to visualize specific radiation-induced vascular changes within the irradiated area of the urinary bladder. Scanning electron microscopy of vascular casts made possible a detailed study of finer vessels in which typical radiation changes, teleangiectases, could be demonstrated.


Hydrostatic pressure technique and intravesical instillation of formalin: new methods for the control of severe bleeding from the bladder. Intractable haemorrhages of the bladder in consequence of wide-spread tumours or of haemorrhagic cystitis secondary to radiation therapy involve serious therapeutic problems. Failure of the conventional therapy to bring the haemorrhage under control imposes more active measures so as to avert the danger of exsanguination. The condition of the patients is, however, generally incompatible with major surgery. In this situation the authors resorted to the hydrostatic pressure technique and to intravesical instillations of formalin. Their observations with these procedures are reported.


Liver function in porstatic carcinoma patients. Liver function tests were carried out for serum zinc turbidity test, icterus index, alkaline phosphatase, bilirubin and transaminases in a series of 222 patients, of whom 119 had prostatic carcinoma, 63 benign hyperplasia of the prostate and 40 congenital abnormality without prostatic trouble. Patients having prostatic carcinoma often displayed abnormally high levels of zinc turbidity test, alkaline phosphatase, bilirubin and transaminases.


Single-needle haemodialysis.

Single-needle haemodialysis. The single-needle method, which greatly simplifies the technique of haemodialysis, was tested for its efficiency by in vitro and in vivo studies. It has proved equal in efficiency to the conventional double-needle techniques. The possibilities of unilateral puncture of the femoral vein in association with the single-needle technique are pointed out.


Diagnostic value of ceruloplasmin, haptoglobin and sialic acid in chronic pyelonephritis. In a group of 84 patients with exacerbated chronic pyelonephritis the authors have determined the blood serum levels of ceruloplasmin, haptoglobin and sialic acid before, during and after antibacterial treatment. They have found a decrease in these levels following treatment. The results of ceruloplasmin, haptoglobin and sialic acid assays could be used as an index for the activity of the pathologic process, as well as in the differential diagnosis between pyelonephritis and glomerulonephritis.


Peritoneal clearances in scleroderma and diabetes mellitus: effects of intraperitioneal isoproterenol. Reduced peritoneal clearances of creatinine and urate were demonstrated repeatedly in a patient with scleroderma and a patient with diabetes mellitus. Urea clearances were not significantly different from usual values. The findings suggest decreased peritoneal membrane permeability and/or area (if urea clearance is flow limited). Clearances increased to usual values with intraperitioneal isoproterenol in the patient with diabetes. There was no effect of isoproterenol in the patient with scleroderma.


Non-deflating Foley catheter.

Non-deflating Foley catheter. The different methods of removal of a non-deflating ureteral catheter were compared with the stylet technique. Two hundred and sixty randomly selected catheters were tested. Overdistention of the balloon with water or air and chemically induced rupture of the balloon produced fragments of various sizes in almost 100%. Our stylet technique failed to demonstrate any of the complications reported in the literature i.e., chemical or mechanical injury to the bladder or retained rubber fragments causing stone formation.


Malignant tumours of the renal pelvis.

Malignant tumours of the renal pelvis. A review of the clinical data of 22 patients with malignant tumours of the renal pelvis, accounting for 10% of the total patient material of renal tumours, is presented. The earliest manifestation was prevalently haematuria, less often pain. In two thirds of the cases the diagnosis was established on radiological evidence and in one third the process remained undetected until surgical exposure of the kidney. The diagnostic difficulties involved by tumours of the renal pelvis and the value of the diagnostic methods are discussed. Nephroureterectomy with excision of a cuff of bladder was carried out in 15, nephrectomy in 5 cases. Three of the 22 patients have survived five years. Early diagnosis followed by total nephroureterectomy without delay may bring some improvement in the poor prognosis of these tumours.


Contribution of a nurse clinician to office practice productivity: comparison of two solo primary care practices. A comparison of two solo primary care practices with similar patient populations reveals a significant difference in productivity. A nurse clinician was employed in the more productive practice. She independently managed 1,848 patient visits a year that would otherwise have required the time and attention of a physician. She contributed to the productivity of the physician by performing some tasks he would normally have performed during visits they managed jointly. It was primarily because of the assistance he received from the nurse clinician that the physician in practice II was 12 percent more productive than the physician in practice I. The nurse clinician and physician managed 31 percent more patient visits during a standard day than the physician in practice I, or a difference of 2,856 patient visits a year. This annual difference is based on a work schedule that could be matched in other practices: an eight-hour day and a 240-day work year.


A managerial accounting analysis of hospital costs. Variance analysis, an accounting technique, is applied to an eight-component model of hospital costs to determine the contribution each component makes to cost increases. The method is illustrated by application to data on total costs from 1950 to 1973 for all U.S. nongovernmental not-for-profit short-term general hospitals. The costs of a single hospital are analyzed and compared to the group costs. The potential uses and limitations of the method as a planning and research tool are discussed.


Utility of the injury severity score: a confirmation. Independent results obtained from Illinois Trauma Registry data confirm an earlier finding of a fixed, monotonic relationship between expected mortality and the Injury Severity Score (ISS) value of injuries sustained in both vehicular and nonvehicular incidents. Further results show the ISS measure to be a good indicator of hospitalization demand from accident victims and suggest that this variable can be used to control for variations in injury severity in comparative evaluations of EMS systems.


A staff allocation model for mental health facilities. This article describes a model for allocating staff within a large psychiatric hospital. The model provides an objective framework within which one can test alternative staff operating policies before making critical decisions concerning the employment of one category of personnel as opposed to another. It is based on objective data describing patient needs and staff functioning patterns, rather than subjective opinions concerning staff deployment. Besides being useful for the short-term deployment of staff and budgetary resources, it can also be used as a long-range planning tool for testing modifications in policy decisions and budget proposals. The algorithm employed, mixed-integer linear programming, is readily available; computer costs and running time are relatively minimal.


Determinants of output in group and solo medical practice. Certain structural and environmental factors other than technical combination of resources and firm size are hypothesized to affect medical practice output. Four groups of variables related to physician attributes and activities, practice organization and patient characteristics, community characteristics, and factors specific to medical groups are examined by regression for correlation with two measures of practice output: gross revenue and total patient visits. Some tentative conclusions are discussed in relation to policies that might increase practice output.


[The management of sudden deafness (author's transl)]. The mean hearing gain (125-8,000 Hz) in 46 cases of sudden deafness treated with low molecular weight dextran was found to be significantly greater (20.9 dB) than that obtained in twelve cases treated differently (9.4 dB). These alternate measures of care included stellate ganglion blockade, vasoactive drugs, sodium bicarbonate infusions, and CO2-insufflation. Early diagnosis and treatment are considered to be crucial for successful therapy: the mean hearing gain in those patients who came for dextran treatment later than one week was less than half of the gain that resulted after treatment beginning within the first week. The results obtained conform with the hypothesis of cochlear microcirculation impairment or "sludging" as the prevalent cause of sudden deafness.


[The facial nerve and the parotid gland (author's transl)]. The modern histological classification of epithelial salivary gland tumours is described. An exact knowledge of the behaviour of each type of tumour permits correct surgical planning. Contrary to the teaching that the superficial parotidectomy is the minimal safe resection, the author feels that in many cases dependent on tumour site, size and histological type, a simple excision is sufficient. The application of microsurgical techniques permits careful and safe surgery.


[Bacterial airborne dispersal during the drilling of infected bone (author's transl)]. The hazards of infection by bacterial airborne dispersal secondary to drilling bone in the surgical treatment of infection of the air spaces of the skull were assessed experimentally. This included estimation of the furthest distance that the cooling fluid, using coloured water, and the bone chips of a dry petrous temporal bone can be thrown, and the spread of the fine dust produced by the drilling using a staph. albus suspension as the rinsing fluid. The drops and bone chips were flung to a distance of about 90 cm in the working area around a cutting burr rotating at 80 000 r.p.m. The fine dust thrown off by cutting and diamond burrs and the infected fluid mist stays suspended in the air for hours and can be carried across the whole room by air currents. The surgeon and operating theatre personnel are therefore always at risk of infection. Preventive measures are discussed.


[Deafness due to topical neomycin (author's transl)]. Today neomycin is almost exclusively given as an ointment in combination with other antibiotics, because of its known oto- and nephrotoxicity. Topical application in high dosage can cause ototoxicity as proved by one patient from this clinic. After laryngectomy and neck dissection for an extensive carcinoma of the epiglottis a 2 X 2 cm dehiscent pyocyaneus infected wound was treated daily with neomycin sulphate solution. A total of 30 gm was given over 3 months during which time the patient became deaf neomycin caused the deafness.


[The significance of tympanometry in pediatric audiometry (author's transl)]. Audiological findings through tympanometry and audiometry were correlated with pathological findings involving the tympanic membranes and the nasopharynx in 232 patients (406 ears) with various hearing disorders in order to determine the probability of a conductive hearing deficit when only tympanogram and clinical findings are known. These measures hold special import to patients in whom exact evaluations of pure tone hearing thresholds are not possible (ie, in small infants and in patients with severe hearing losses in low frequency ranges).


[Results of otoplasty (author's transl)]. 77 patients with uni- or bilateral otoplasty have been reviewed between 6 months and 5 years postoperatively. Surgery had been performed using a modified Converse technique. A comparison was made between the objective results and the patient's satisfaction. Using our own classification, we listed 64.9% as good results and 3.9% as failures, suggesting a reoperation. 31.2% of the cases demonstrated only some improvement. Evaluating our results listed as "good", the average distance helix: planum mastoideum, measured between the upper and middle third of the ear, was 18.8 mm and between the middle and lower third 18.0 mm.


[Tracheal stenosis in children and its operative management (author's transl)]. The problem of tracheal stenosis in children is discussed, with emphasis placed on subglottic disease. The primary etiologies for the stenosis were chronic intubation and emergency tracheostomies following accidents. The operative technique described utilizes vertical division of the trachea and cricoid in the midline. The margins are then stretched laterally and sutured to skin incision lines. Granulations, scar and dislocated cartilage are removed, and the denuded area covered with free mucosal grafts or with pedicle skin flaps. After reestablishing an adequate airway (with use of an acrylic prosthesis for several weeks), the tracheal groove is closed with a composite graft from the auricle. A tracheostomy is left in place an additional 2-3 weeks, while the raw neck area is resurfaced by a transposition flap from adjacent skin. The technique has worked well since 1971 in three children (aged 3, 5 and 7 years), and was also performed successfully on five adult patients.


[The use of microlaryngoscopy in phoniatry (author's transl)]. Definite diagnostic advantages exist in the use of combined microlaryngoscopy and microstroboscopy in vocal rehbilitation since objective determination of vocal pathology can be made. The phoniatric considerations used in determining the indications for operative investigation are described. Reference is made to specific clinical problems, including the "hormone voice" in the Reinke edema from medications used in therapy and arytenoid dislocations from insufflation anesthesias. The postoperative prognosis after endolaryngeal surgery depends on the effectiveness of the surgical intervetion and the appropriate phoniatric-logopedic care employed. The author suggests that post-operative voice pauses should be minimized and not depend upon complete re-epithelialization of operative sites. Phoniatric and logopedic treatment used is based on considerations for appropriate vocal cord movements. The advantages of endolaryngeal faradization for vocal rehabilitation are discussed. In addition, the theoretical considerations of fitness for work are also discussed.


[Operative repair of the traumatically disrupted ossicular chain (author's transl)]. Consequent to the large number of skull injuries following traffic accidents, a significant number of patients experience traumatic disruption of the ossicular chain. Although most of these injuries can be managed by standard otologic procedures, this communication deals with three special clinical problems. Although not previously encountered, the diagnosis in the first could be made by otoscopy. In the second, infracture of the malleolar head had produced injury to the facial nerve which was exposed in its horizontal course. Although transposition of the malleus was required in repair, significant interference with hearing had not occurred since a spontaneous tympanoincudopexy had been produced by the injury.


[Dysphonia in acromegaly (author's transl)]. Acromegalic dysphonia is described in a series of 80 acromegalic patients. Subjective dysphonia was observed in most patients, objective dysphonia, however, wasnoted in only 50% of the cases. The patients with objective dysphonia usually had progenia, moderate to high acromegalic activity and duration of disease of more than five years. The different factors of importance for the development of acromegalic dysphonia are summarized.


[Management of median cysts and fistulae (author's transl)]. The total extirpation of thyroglossal duct remnants with resection of the mid hyoid bone is reported as the only method for successful surgical therapy. Convoluted ducts of cysts and fistulae must be dissected to the base of the tongue and excised. As our cases demonstrate, recurrences will be avoided and revision surgery, when required, will be most successful.


[Puncture of the maxillary sinus (author's transl)]. In some texts on operative technique it is recommended, when puncturing the maxillary sinus via the inferior meatus, to aim towards the outer canthus of the eye. It is demonstrated on a skull that aiming at the inner canthus avoids the danger of piercing the premaxillary tissue and in addition the diameter of the sinus is greater at this angle.


[Treatment of Menière's disease with betahistine (author's transl)]. Betahistine was gien to 86 patients with Meniere's disease in a thric daily dose of 8 mg. All patients except for three had earlier been treated medically without success. Symptomatic improvement occurred overall in 82,5%, including in 66% ear pressure symptoms, in 59.5% headache in 57% tinnitus, and in 35% hearing, although this latter statistically was not confirmed. The duration of administration of betahistine is therapeutically important and benefit from 4 months' continued use was demonstrated. After stopping treatment, the therapeutic effects were maintained and more than 6 months later improvement in hearing and ear pressure symptoms was still recorded. There was though a deterioration in symptoms of vertigo, tinnitus and headache in 18% over the same period. The shorter the duration of the symptoms the better the therapeutic effect gained. Improvement estimations of 81% in patients affected for up to 1 month, of 65% in patients affected from 1 to 12 months, and of 50% in patients affected more than one year were obtained. These results compare averagedly with the widely varible results of others. The management of Meniere's disease with betahistine can be regarded as an improvement in the conservative therapy of this disorder.


The fistula and Hennebert tests.

The fistula and Hennebert tests. The fistula and Hennebert tests are used to detect the structural integrity of the bony labyrinth or to detect when the membranous labyrinth is in contact with the footplate of the stapes. Both tests may be administered with the manometer of an electroacoustic impedance instrument. When vertigo is a symptom, these tests should be a part of the routine impedance test battery.


Audiologic and metabolic findings in 90 patients with fluctuant hearing loss. Fluctuant hearing loss is a common occurrence. It is difficult to diagnose in its early stages when hearing thresholds are near normal and the only complaints the patient has are of fullness and tinnitus. Audiologic tests are helpful in confirming the diagnosis. Impedance measurements are an accurate assessment of middle ear status and can assist in localizing the fullness experienced by these patients. Site of lesion tests and discrimination scores at various sensation levels are sensitive indexes of disease activity. Observations during medical treatment of 90 patients with metabolic dysfunction (hyperlipoproteinemia: hypoglycemia; hypothyroidism) suggest that discrimination scores fluctuate more widely than do pure tone thresholds over a period of time. Thirty patients were given complete audiologic testing after dietary management and treatment. All reported relief from tinnitus and fullness, and 15 or 50% showed improved audiograms and discrimination scores. Any change in the energy reserve or metabolic rate of the inner ear by a systemic metabolic dysfunction can contribute to or cause sensorineural hearing loss. Energy flow from metabolic sources is needed to transduce the acoustic stimuli into neural excitation patterns. The presence of any systemic metabolic dysfunction can be expected to contribute to and cause fluctuant hearing loss.


Dichotic listening in adults with sensorineural hearing loss. Digits and consonant-vowel (CV) nonsense syllables were presented dichotically to 36 normal-hearing subjects and 36 subjects with bilaterally symmetrical sensorineural hearing loss. The normal-hearing subjects performed significantly better in the recall of both digits and CV nonsense syllables, and recall decreased significantly as the degree of hearing loss increased. The expected right ear advantage was observed for the normal-hearing subjects on both tests. As a group, the hearing-loss subjects showed no significant ear preference, and ear preference did not vary significantly with the degree of hearing loss. However, individual hearing-loss subjects showed marked ear asymmetry for the dichotic digits. For both dichotic tests, individual ear preference increased as the degree of hearing loss increased. Significant but low correlations were observed between better ear speech discrimination scores for the hearing-loss subjects and the preferred ear for dichotic CV nonsense syllables.


Performance by cortical lesion patients on 40 and 60% time-compressed materials. Tape recordings of time-compressed (40 and 60%) monosyllables were administered to 11 patients with diffuse unilateral temporal lobe lesion, 4 hemispherectomy patients, and 16 patients with discrete unilateral temporal lobe lesion. Time compression was accomplished with the Fairbanks electromechanical apparatus, which allowed temporal compression but did not introduce frequency distortion. The results revealed that with 60% time compression, all patients with diffuse unilateral cortical lesion showed breakdown of speech discrimination in the ear contralateral to the lesion. Patients with discrete unilateral cortical lesion generally did not demonstrate breakdown with the 60% time-compressed materials.


Granulomatous enteritis in nine horses.

Granulomatous enteritis in nine horses. Granulomatous enteritis was diagnosed in 9 horses between 1 and 11 years of age. The complaint in all cases was persistent weight loss. Four of the horses had chronic diarrhea. Two consistent diagnostic features were hypoalbuminemia and decreased phagocytic activity of mesothelial cells in the peritoneal fluid. In 2 cases the diagnosis was confirmed by biopsy of the rectal mucosa. Remaining cases were definitively diagnosed by exploratory laparotomy and biopsy or at necropsy.


Diagnosis and surgical treatment of cystlike lesions of the equine paranasal sinuses. Development of cysts in the equine paranasal sinuses is probably a congenital disease; however, signs may not appear for several years. In 4 cases, clinical signs were observed when fluid accumulation within the cysts resulted in nasal discharge or facial swelling, or when secondary infection occurred. Treatment required surgical removal of the lining membrane and other involved tissues. Postoperative care included lavage of the sinuses and systemic antibiotic therapy.


Temporal summation of the acoustic reflex in normal and sensorineural hearing-impaired ears. Psychophysical and acoustic reflex temporal summation measures were obtained on normal-hearing and sensorineural hearing-impaired persons. Bursts of one-third octave noise with center frequencies of 500, 1000, 2000, and 4000 Hz and durations of 15, 20, 50, 100, 200, and 300 msec were used as stimuli. Reflexes were obtained using an acoustic impedance measuring technique. Results demonstrated that the duration of the noise stimuli had a profound effect on the acoustic reflex response and that the ear with Ménière's disease was clearly distinguishable from the normal ear by both psychophysical and acoustic reflex temporal summation measurements. The presbycusic subjects were separated from the normal subjects to a greater extent in the psychophysical data at the higher frequencies. The reflex thresholds for the noise bands and durations used in this study occurred at lower sound pressure levels than those previously obtained. The normal-hearing subjects failed to show any differences in either psychophysical or acoustic reflex temporal summation as a function of stimulus frequency.


Innervation of the equine hip and stifle joint capsules. The hindlimbs of 3 ponies and 3 horses were dissected. The hip joint capsule was found to receive articular nerve fibers from the femoral, obturator, cranial gluteal, and sciatic nerves. The nerve fibers were distributed to the fibrous joint capsule and associated capsular ligaments. The stifle joint capsule was found to receive articular branches from the femoral, saphenous, obturator, common peroneal, and tibial nerves. The fibers terminated in the joint capsule, fat pad, patellar and collateral ligaments, and the internally situated meniscal and cruciate ligaments.


Sebaceous gland adenomas in dogs.

Sebaceous gland adenomas in dogs. In a review of neoplasm registry records at Kansas State University (1961 through 1971), 162 sebaceous gland adenomas were reported in 31 breeds of dogs, representing 5.0% of 3,240 neoplasms recorded. Mean age of the affected dogs was 9.5 years. Females accounted for 56.1% of the recorded sebaceous gland adenomas. The tumors were removed surgically for biopsy in all dogs; 24 dogs had multiple concurrent skin neoplasms of a different cell type, and 7 dogs had recurrence of sebaceous gland adenomas, without metastases, and required further surgery. The skin of the hindquarters, abdomen, and thorax was a principal site (54%) of the sebaceous gland adenomas.


Evaluation of a vaccine for control of streptococcic lymphadenitis of swine. Three tirals were conducted to evaluate the use of a vaccine for control of streptococcic lymphadenitis of swine. Clinically normal swine were vaccinated orally, according to the manufacturer's instructions. Unvaccinated controls and the vaccinated pigs were subsequently inoculated with a virulent strain of the etiologic agent, group E Streptococcus, serotype IV. At necropsy, 47 of the 51 vaccinated pigs (92.1%) were free of cervical abscesses, whereas 20 of the 21 control pigs (95.2%) developed cervical abscesses.


Porcine abortion caused by Actinobacillus equuli. Actinobacillus equuli was isolated from an aborted porcine fetus. Fetal lesions of peracute embolic septicemia were similar to those seen in septicemic actinobacillosis of older swine and other species. This case represented an individual rather than a herd abortion problem.


Cranial cruciate ligament repair in a calf. A 1-month-old calf was unable to use its right pelvic limb because of rupture of the cranial cruciate ligament. The ligament was replaced with a wedge of bone from the cranial one-third of the patella and the attached portion of the middle patellar tendon. Postoperative complications limited function of the joint.


Effect of mechanical factors on the relation between rate and depth of breathing in cats. In anesthetized tracheotomized cats we compared the time sequence of ventilatory events with neurological events (electrical activity of the diaphragm) during the breathing cycle. We found that under control conditions a phase shift existed between the neurological and the spirometric duration of inspiration, amounting to about 150 ms. This phase shift was increased by increasing the time constant of the respiratory system (resistive loading) and decreased by decreasing it (elastic loading). These phase shifts resulted in a difference in the appreciation of the volume responsible for the termination of inspiration (Hering-Breuer inhibition) because the volume corresponding to the end of the neurological event was somewhat smaller than the final tidal volume reached.


Adaptation of anesthetized men to breathing through an inspiratory resistor. Normal men anesthetized with methoxyflurane rebreathed carbon dioxide under two conditions. In one case they breathed most of the time through a low-resistance circuit and an inspiratory resistor of 40.4 cmH2O/1-s-1 was applied at intervals. In another case they breathed most of the time through the resistor and were allowed occasional free breaths. There were no differences between the two types of runs in tidal volume, respiratory frequency, duration of inspiration of loaded or unloaded breaths, or in amplitude or shape of occlusion pressure waves. It is concluded that the reaction of conscious men to an inspiratory resistive load, consisting of a compensatory augmentation of neural drive to respiratory muscles that does not depend on a chemical stimulus, is absent in anesthetized men.


Physiological and behavioral reactions to repeated tail cooling in the white rat. The purpose of the study was to examine a) the effect of local cooling on the metabolic rate, b) the effect of metabolic rate on the peripheral circulation, and c) acclimation to local cooling. After habituation to the experimental situation, 10 white rats had their tails exposed to ice water for 40 min/day for 37 days. Metabolic rate and tail temperature were measured. There was a conspicuous increase in oxygen consumption during the first 10 min of each cold exposure. This increase did not change significantly through the series. The metabolic rate during cooling was significantly reduced in the last half of the series. Tail temperature was significantly influenced by metabolic rate and increased significantly from the beginning of the series to the middle, and decreased from the middle to the end. Time of onset of the cold-induced vasodilatation decreased in the middle of the series and increased again at the end. These paradoxical findings are believed to be due to interplay between orienting reactions and habituation. It is pointed out that habituation may counteract acclimation.


Effects of intermittent hyperbaric oxygen on guinea pig lung elastin and collagen. The effect of high oxygen pressure on collagen and elastin turnover in lung parenchyma tissue was studied in guinea pigs. Three groups of animals was used. One group (I) was given a clinically excessive exposure of 3 h daily for 9 days of 3 ATA oxygen. A second group (II) was given 3 ATA compressed air on the same schedule, and a third (III), a control, was given the same handling conditions only. Collagen and elastin which amounted to 10.45 and 4.62 mg, respectively, per 100 mg dry defatted parenchymal tissue was labeled with [14C]proline injected ip. Connective tissue protein turnover was estimated by labeling half of each group before exposure (a); effects on biosynthesis were determined by labeling the other half postexposure (b). No differences in hydroxyproline specific activity of collagen fractions or elastin were found with respect to either biosynthesis or turnover. Alveolar wall length-tension measurements were not changed. Since exposures were in excess of those used for treatment of gas gangrene, ischemic burns or wound healing, these results suggest that the metabolism of lung connective tissue is unaffected by the short-term exposure to hyperbaric oxygen.


Gas-blood CO2 equilibration in parabronchial lungs of birds. We have conducted two experimental series in the chicken in order to study CO2 exchange in the parabronchial lungs of birds. In the first series, the animals were artifically ventilated and end-expired PCO2, PE'CO2, was measured and compared with mixed venous PCO2, PVCO2. On the average, PECO2 exceeded PVCO2 by 2.8 Torr. In the second series, rebreathing was used to investigate the mechanism of this positive (PE'-PV)CO2 difference. Lung gas PCO2 was found to equilibrate with PVCO2 if both CO2 and O2 exchange in the lung was abolished during rebreathing. Only if O2 uptake continued, we observed a positive gas-to-mixed venous blood PCO2 difference. The results suggest that positive gas-blood PCO2 differences both during rebreathing and steady-state ventilation are brought about by the Haldane effect. Model calculations show that in the homogeneous avian lung, unlike in the alveolar lung, the Haldane effect can produce positive (PE'-PV)CO2 differences during steady-state breathing due to the peculiarities of the crosscurrent arrangement and parabronchial ventilation and blood perfusion.


Uterine work in parturition.

Uterine work in parturition. This  paper presents a theoretical analysis relating work expended by the uterus to the synergistic relationship between intrauterine pressure (IUP) and cervical dilatation (CD). By utilizing a geometrical model for the fetal presenting part which is assumed to be in contact with the cervix, the changes in internal volume of the uterus with each contraction can be shown to be functionally related to cervical dilatation. Thus work, expressed in terms of foot-pounds, can be calculated using the integral of pressure times incremental volume. By simulating intrauterine pressure and cervical dilatation with continuous analytical wave forms, the alterations required in uterine work to dilate the cervix are calculated for various wave-form aberrations which are seen in clinical situations. The wave-form aberrations are applied to an elastic cervical model as well as a viscoelastic model. Using the principles of thermodynamics the areas of the fetouterine complex which absorb the work generated by the contractions are defined. It is shown that the efficiency of the contractions to dilate the cervix can be calculated by evaluating the work expended in these various areas of energy absorption. The purpose of this paper is to present the theory upon which clinical findings in obstetrics can be based so that conclusions drawn will be technically sound.


Plasma renin activity, angiotensin II, and aldosterone during intense heat stress. Plasma renin activity (PRA), angiotensin II, and aldosterone levels, arterial blood pressure, and heart rate of six male students were investigated during and after heat stress in a sauna bath. Increased PRA, angiotensin II, and aldosterone levels were found both during and after sauna. The greatest mean increases in PRA (94.9 +/- 10.4% SE, P less than 0.005) and angiotensin II (196 +/- 54.7% SE, P less than 0.02) were observed at the end of the heat stress (at 20 min), and that in plasma aldosterone (505 +/- 209% SE, P less than 0.02) 30 min after the sauna. The heart rate roughly doubled during the heat stress and there was a transient increase followed by a decrease in systolic blood pressure and a decrease in diastolic blood pressure. This study demonstrates that intense heat stress can cause remarkable changes in the three main components of the renin-angiotensin-aldosterone system.


Evaluation of the isolated paced rat heart. Ventricular performance and coronary flow in Langendorff perfused rat hearts were measured over a wide range of perfusion pressures and heart rates. A change in aortic pressure from 60 to 120 mmHg induced a linear increase in coronary flow, ventricular systolic pressure, and contractility. Ventricular pacing from 300 to 600 beats/min under a constant afterload had no effect on coronary flow. Systolic pressure remained stable up to 400-450 beats/min and then decreased 14% at 600 beats/min compared to the nonpaced controls. When contraction rate exceeded 450 beats/min diastolic pressure progressively increased as the heart rate was elevated. Contractility decreased rapidly between 450 and 600 beats/min under all perfusion pressures. These data indicate that this heart model is physiologically stable with heart rates less than 450 beats/min and may be useful in studying tachycardia-induced work overload.


Exercise stress and enzyme-induced emphysema. Rats were exposed to an aerosol of 10% papain for 8 h found in pilot studies to produce marked emphysema. One week after exposure some animals were forced to exercise in a motor-driven activity wheel 2 h daily for 4 wk, while others remained at rest. Another group of rats which served as the control were exposed to saline under the same conditions and divided into exercise and rest groups. Elastic recoil pressure (Pst) of lung was measured from static deflation pressure-volume curves with air and saline. Pst measured in air-filled lungs was not significantly different between the emphysema-rest and emphysema-exercise groups. When inflated with saline the Pst was significantly reduced in the emphysema-exercise compared to the emphysema-rest group at high and mid (100, 80, 60%) lung volumes. Pst in air- and saline-filled lungs was not significantly different between the control-rest and control-exercise groups. We therefore conclude that mechanical stress resulting from physical exercise decreased Pst of lung tissue in emphysematous rats.


Role of the carotid bodies in the heart rate response to breath holding in man. To investigate the role of the carotid bodies in regulating the bradycardia of breath holding in man, we studied heart rate (HR) responses to prolonged breath holding (BH) in five asymptomatic asthmatic patients whose carotid bodies had been resected (CBR). Seven normal subjects served as controls. BH experiments were randomly initiated with single breaths of 100%, 21%, or 12% 92. During BH with 21% O2, normal subjects displayed the typical bradycardia; this response, however, was attenuated with the other O2 concentrations. In contrast, the CBR subjects manifested BH tachycardia which was inversely proportional to the O2 tension. HR increased in be CBR group by 5%, 31%, and 45% during BH with 100%, 21%, and 12% O2, respectively. These results demonstrate that the bradycardia of BH in normal man is under the influence of the carotid bodies. During BH and in the absence of carotid bodies, an O2 tension-dependent tachycardia is unveiled.


Decompression-induced decrease in nitrogen elimination rate in awake dogs. Formulation of safe decompression procedures still requires unproven assumptions regarding both gas equilibration rates and the associated ascent criteria. Although the assumption of symmetry of uptake and elimination rates has been suspect for several years, few data are available. Measurements of actual mixed venous blood nitrogen content [vN2] during compression and following decompression in chronically catheterized awake dogs have clearly demonstrated that desaturation is markedly slower than saturation, and that this effect can be imposed by decompression. The disappearance of arteriovenous nitrogen concentration differences during desaturation following a decompression that produced decompression sickness indicates that cardiopulmonary and cardiovascular changes induced by mechanisms associated with decompression per se can potentiate its deleterious effects. Current US practices do not provide for such asymmetry, while those used in the UK have incorporated this in their models for the last decade.


Depressed myocardial function in the goat at high altitude. To determine if depressed myocardial function contributes to the reported decrease in cardiac performance at high altitude, six chronically instrumented, unsedated goats were studied before, during, and after 2-wk exposure to hypobaric hypoxia (PaO2 44 mmHg). Undistorted ventricular pressure wave form was obtained from a miniature transducer implanted in the left ventricular cavity. The relationship between (dP/dt)/28P and P was extrapolated to obtain Vmax as an index of myocardial function. With beta sympathetic blockade (practolol) and pacing to reproduce heart rates, Vmax was uniformly and significantly depressed (P less than 0.01) during chronic hypoxia, and returned to control values following descent to low altitude. Likewise, stroke volume following saline infusion was decreased at high altitude and returned to control values following descent. Acute relief of hypoxia at high altitude by administration of 100% oxygen by mask did not reverse the depressed Vmax. These findings indicate that chronic hypobaric hypoxia produces a depression of myocardial function which is reversible by chronic but not acute relief of hypoxia.


Myocardial interaction between the ventricles. The myocardial interaction between the ventricles was studied using isolated, flow-perfused, paced rabbit hearts beating isovolumically. In general, increasing left ventricular (LV) volume increased right ventricular (RV) diastolic and developed pressures. In particular, with a peak RV volume (RVV), increasing LV volume (LVV) from zero to two-thirds of its peak volume increase RV diastolic pressure by 1.7 mmHg (N=10, P less than 0.001) and RV developed pressure by 1.5 mmHg (N=10,P less than 0.001). For the LV, small RVV caused LV diastolic and developed pressure to increase, while large RVV increased LV diastolic pressure but decreased LV developed pressure. With a LVV held at two-third of peak volume, increasing RVV from zero to its peak volume caused LV diastolic pressure to increase by 2.5 mmHg (N=10,P less than 0.001) and LV developed pressure to decrease by 2.0 mmHg (N=10, P less than 0.001). The position of the interventricular septum correlated with LV diastolic pressure and RV diastolic and developed pressure changes (P less than 0.01). The results demonstrate that the diastolic and developed pressure-volume relationships of either ventricle can be acutely altered by varying the volume of the other ventricle.


Mechanics of the canine diaphragm.

Mechanics of the canine diaphragm. Diaphragmatic force-length behavior was assessed in anesthetized dogs using two techniques. One employed measurements in a diaphragm strip with intact nerve and blood supply; the second related transdiaphragmatic pressure (Pdi) to direct estimates of diaphragmatic tension from strain gauge arches during bilateral, tetanic, supramaximal phrenic nerve stimulation. In strip preparations the diaphragm exerted active force at lengths as short as 40% of resting in situ length (Lo), and maximal force was registered at a length averaging 25% greater than Lo. This suggested a broader effective length range for the diaphragm as compared to other skeletal muscles. In the intact preparation both Pdi and directly measured diaphragmatic tension were inversely related to lung volume and when they were used to calculate the diaphragm's effective radius of curvature (r), r was found to change little or decrease at large lung volumes rather than increase as theory would predict. These findings suggest that length tension characteristics outweigh geometric considerations in explaining the diaphragm's function in normal dogs and probably normal men.


Modulation of carotid baroreflex responsiveness in man: effects of posture and propranolol. Carotid baroreceptors were stimulated with graded neck suction in supine and standing volunteers, before and after autonomic blockade, to determine the influence of posture on baroreflex responsiveness. Propranolol significantly augmented baroreflex pulse interval prolongation in the supine position. Upright posture did not modify baroreflex pulse interval responses prior to propranolol, but significantly augmented responses after propranolol. The results suggest that standing enhances baroreflex sensitivity, but that under normal circumstances, this effect is masked by beta-adrenergic stimulation. Augmentation of baroreflex pulse interval prolongation in the supine and standing positions by propranolol may contribute to the effectiveness of this drug in angina pectoris and labile hypertension.


Distribution of pulmonary resistance: effects of gas density, viscosity, and flow rate. Theoretical predictions of the distribution of inspiratory viscous pressure loss were made for canine and human pulmonary airways for gases with varying density and viscosity at different pulmonary flow rates. We predicted that in canine or human airways when tracheal flow was turbulent, most of the total calculated pressure loss would be in the first few branchings of the bronchial tree; however when tracheal flow was nearly laminar inspiratory pressure loss would be spread more uniformly along the airways. To test these predictions an airway catheter was used to partition total pulmonary resistance (RL) in five anesthetized dogs. On air the catheter was positioned such that the mean resistance mouthward of the catheter tip (Rc) at a flow of 0.5 1/s was 63% of RL. At the same catheter position Rc was 87% of RL when the dogs were breathing a mixture of 80% sulfur hexafluoride-20% oxygen and resistance was determined at 1.0 1/s. Rc was 50% of RL when the dogs were breathing a mixture of 80% helium-20% oxygen and resistance was determined at 0.25 1/s. Thus altering gas physical properties and flow rates changed the distribution of pulmonary resistance as predicted.


Localization of airway constriction using gases of varying density and viscosity. The relationship between the major site of airway constriction and change in total pulmonary resistance while breathing gases of varying density and viscosity was studied in five anesthetized dogs pretreated with atropine. Using an airway catheter, central and peripheral components of pulmonary resistance were measured by forced oscillation. Total pulmonary resistance was measured at 0.5 1/s with lungs air-filled, at 0.25 1/s with the lungs filled with 80% helium-20% oxygen (RL-He), and at 1.0 1/s with 80% sulfur hexafluoride-20% oxygen (RL-SF6). Intravenous histamine infusion resulted in a predominantly peripheral resistance increase as determined by the airway catheter and a much larger percentage increase in RL-He than in RL-SF6. Tracheal banding produced a purely central resistance increase and a greater change in RL-SF6 than in FL-He. These results support theoretical predictions that the predominant site of airways constriction can be determined without on airway catheter by comparing relative changes in total pulmonary resistance using different flow regimes.


Determinants of regional distribution of a bolus inhaled from residual volume. The volume of lung at residual volume (RV) which fails to receive an inhaled tracer bolus (EXV) was quantitated in 13 normals by comparison of a scintigram of the distribution of a tracer bolus inhaled from RV (BORV) with a scintigram at RV of lung equilibrated with the tracer (EQRV). EXV was found in the dependent lung in the erect position in all subjects but also occurred to a lesser degree at the apex in 11 of 13 subjects. Basal EXV ranged from 1 to 7% of TLC, and unlike apical EXV increased with age (r= 0.91, P less than 0.01). EXV in the decubitus position shifted largely to the dependent lung with none remaining in the original erect apical and basal locations, demonstrating that gravity determined EXV location. Nitrous oxide, which is highly diffusible, failed in four subjects to carry the tracer to basal EXV even though perfusion was documented to persist to this area, implying basal EXV airways were closed, not narrowed. In one of the four subjects apical EXV was readily definable. Nitrous oxide carried tracer into this region, implying patent apical EXV airways.


Storage telemetric system for detection of radionuclide tracers in humans. An external-storage telemetric device for continuous detection and registration of radionuclide tracers in humans is described. The weight of the system is 600 g. A pocket-sized ECG cassette tape recorder with 24-h continuous registration constitutes the storage unit. Two end-window GM detectors (Philips 18515) are used as surface detectors. Both gamma- and beta-emitters are detected by this equipment. The linear range is 100 counts/s. Renal excretion of [125I]iodide during 30 h in a normal person is shown. The disappearance rates are 0.1 h-1 during the day and 0.05 h-1 during the night. The coefficient of variation of the individual slopes has been calculated to less than 5%. A comparison with the analog radiotelemetric equipment is shown. The storage telemetric equipment can be applied outside the hospital, when the patient is ambulatory.


Ventilation-perfusion ratio obtained by a noninvasive frequency response technique. Results of animal experiments using sinusoidal changes in inspired halothane concentration showed that the ratio of variation in end-expired concentration to the variation in inspired concentration reached a plateau in the Bode diagram. With the help of an uptake and distribution model, the interpretation of the results showed that the level of the plateau is determined by the overall ventilation-perfusion ratio. With a good selection of input frequency, tracer agent, and known ventilation, the ventilation-perfusion ratio and the lung perfusion can be consequently obtained noninvasively. Mean ventilation-perfusion ratio was determined with 20 human voluteers. At rest a mean ratio was found of 0.87 +/- 0.28 (SD). At a work load of 90 W a mean ratio was found of 1.19 +/- 0.19 (SD). In two individuals reproducibility and influence of CO2 was studied. At rest without additional CO2 the ventilation-perfusion ratio was 0.71 +/- 0.06 (SD) obtained with a constant breathing rate of 10/min. At an end-expired CO2 level of 6% the ventilation-perfusion ratio was increased almost 2.5 times. The calculated perfusion with and without increased end-expired CO2 levels under the same work load were well reproducible.


Novel telemetric system for extraluminal measurement of gastrointestinal motility. A frequency-modulated, telemetric system with a transducer sensitive to variation in distance between two points was developed and used to measure in vivo small intestinal motor function in unanesthetized dogs. The construction of the system and one application of it to the study of gastrointestinal motility is described. Data were recorded after fasting, 1 h after feeding a standardized meat meal, and after intravenous injections of pentagastrin. A significant increase in motility was seen after pentagastrin injections and feeding as compared to the motility pattern seen in a fasting animal, and the telemetric system was proven adequate for in vivo measurement of motility of the gastrointestinal tract.


Small inexpensive anesthetic apparatus for rats. An anesthetic apparatus is described that is capable of delivering easily controlled, constant ether-air mixtures to rats and other small laboratory animals. The apparatus is readily calibrated and is stable for extended periods of time under laboratory conditions. In  addition, the apparatus can be constructed of commonly available components.


Mechanical apparatus for rigid suspension of the spinal column in mammals. An apparatus is described for rigid suspension of the spinal columns of mammals ranging in size from large dogs to small rabbits. This apparatus is unique in that the animal is suspended on its side, allowing free access to the entire spinal column for spinal cord studies and free access to the thoracic and abdominal regions for heart, lung, and visceral studies that may require simultaneous surgical procedures in both ventral and dorsal regions.


Estimation of cardiac output by an N2O rebreathing method in adults and children. A nitrous oxide rebreathing method was used to measure recirculation time and cardiac output (as pulmonary blood flow) in adults and children during exercise. The method was compared with the indirect (CO2) Fick rebreathing method in almost simultaneous measurements of cardiac output. Recirculation time varied from about 15 s at rest to 8.5 s at high levels of exercise, and was slightly longer in children than adults. Cardiac output estimated by both methods was within the normal range for children and adults, being lower for a given oxygen consumption in children. For the adults the mean intrasubject variability of the N2O rebreathing method, measured as the coefficient of variation of cardiac output, was in the range of 6-8% at all levels of work. This was lower than reported for other N2O rebreathing methods, and similar to values based on the indirect (CO2) Fick, direct (O2) Fick, and dye-dilution methods of estimating cardiac output. The method is therefore proposed as a noninvasive technique suitable for rapid, accurate, and reproducible measurements of cardiac output.


Simple method of hepatic venous blood sampling in the rat. An improved method of hepatic venous blood sampling by catheterization in rats is proposed and applied to the measurement of hepatic blood flow (HBF) by the continuous ICG infusion method in normal rats and in rats treated chronically with CC1(4). The value of HBF determined by the present method was 0.90 +/- 0.17 (SD) ml/min per g liver under ether anesthesia, which was consistent with the reported values determined by other more complicated methods. The applicability of the present method was also shown in CC1(4) chronic intoxicated rats, to give 0.64 +/- 0.11 ml/min per g liver of HBF.


Electrochemical sensor for continuous transcutaneous PCO2 measurement. A sensor suitable for continuous transcutaneous PCO2 measurements is described. The sensor consists of an antimony-antimony oxide electrode in combination with a silver-silver chloride reference electrode, bathed in an electrolyte and covered by a Teflon membrane. A servo-controlled heater unit was used to maintain the sensor's temperature and to produce local hyperemia. The resulting oxidation-reduction potential under constant temperature is a linear function of the logarithm PCO2. Response time (95%) to step changes in PCO2 from 27 to 70 mmHg was 2.7 +/- 0.3 min. Following a 12-h "aging" time, the electrode exhibited a minimal drift of 5.2 +/- 2.2 mV for 16 h, representing an average PCO2 drift of 0.5 mmHg/h. This sensor was applied on three rabbits and on five human volunteers, and found satisfactory under normal physiological conditions.


Collaborative study of accelerated development of latent fingerprint images on paper by application of steam. Nine latent fingerprint examiners participated in a collaborative study in the use of a steam iron to accelerate chemical development of latent images on bond and newsprint papers treated with a 0.5% solution of ninhydrin in acetone. Four latent images were placed on each paper by the Associate Referee during an 8 hr period. The papers were paired and numbered 1, 2, and 3. Three pairs were mailed to each collaborator who treated Pair 1 by dipping, Pair 2 by brushing or swabbing, and Pair 3 by spraying. After air-drying, the papers were subjected to heat and steam from a household steam iron until the images developed. The average time for developing all images was 5.8 min/paper. Of the total images available, 92.1% were developed to some degree; 47.9% of these images or 43.5% of all images were identified by the collaborators. The method has been adopted as offical first action.


Uses of field desorption mass spectrometry in the pharmaceutical industry. Field desorption (FD) is a gentle method of ionizing molecules from the solid state. The method is still in its infancy and remains more of an art than a science. Purines, pyrimidines, pteridines, and nucleosides represent some of the compound classes which are studied repeatedly in our laboratory. Often the primary information sought is the molecular weight. Many of these compounds are thermally unstable or nonvolatile. In these instances, FD mass spectrometry has proven to be quite helpful. Molecular weights are obtained in a short time, eliminating the need for more time-consuming derivatization or chemical degradation methods. FD has been applied to the study of drug metabolism and has shown great promise in determining polar metabolites, including direct analysis of glucuronide, sulfate, and amino acid conjugates. Some problems have been encountered in handling samples of biological origins. Salt impurities introduced by the separation procedure may interfere with the desorption process. Cluster ions and background noise make it difficult to assign molecular ions, and some compounds do not yield molecular ions with FD.


Applications of mass spectrometry to the analysis of mycotoxins. Methods of identifying mycotoxins by mass spectrometry are reviewed, with special reference to the value of a complete listing of known fungal metabolites, arranged by molecular weight. Such a list is applied to the identification of various mycotoxins, and mass spectrometry is applied to the structural elucidation of dimethylnidurufin and ostreogrycin A.


Review of the metabolism and mode of action of cyclophosphamide. A review of recent studies of the pharmacology of cyclophosphamide is presented. Particular attention is paid to the use of mass spectrometry in the identification of the active compound phosphoramide mustard as a circulating human metabolite of cyclophosphamide, the development of an assay method for cyclophosphamide, phosphoramide mustard, and nornitrogen mustard, and a demonstration that alkylation by phosphoramide mustard proceeds through a symmetrical aziridinium ion.


Gas-liquid chromatography and mass spectrometric ion selective detection of sterigmatocystin in grains. A method was developed for direct gas-liquid chromatographic-mass spectrometric (GLC-MS) analysis of nonderivatized sterigmatocystin in wheat, rice, barley, and corn. Sterigmatocystin was extracted from spiked grain samples by 2 methods, both of which yielded high recoveries of 14C-labeled sterigmatocystin (greater than 90%). Extracts were cleaned up by gel permeation chromatography on polystyrene with tetrahydrofuran as the eluant. Chromatography of 14C-labeled compound indicated good recoveries (greater than 90%). The GLC-MS system was modified to give an all-glass chromatographic pathway to the ion source. Short glass or quartz columns packed with silicone liquid phase on inert supports gave the best results. Trace levels of sterigmatocystin were very labile in all gas chromatographic systems and levels below 5 ppb in grains were detected only with great difficulty. The GLC-MS system was utilized in the mass fragmentography mode, with selective ion monitoring of the m/e 295, 306, and 324 peaks. These ions were present in only trace levels in all control grain samples, indicating minimal interference from other compounds. The limit of accurate detectability (20 ng) on spiked grain samples was lower than previously reported. Lower levels of sterigmatocystin (1 ppb or 4 ng on column) could be detected in grains by using the mass fragmentography mode, but these levels could not be measured accurately.


High-performance liquid chromatographic determination of L-aspartyl-L-phenylalanine methyl ester in various food products and formulations. A simple, rapid, and specific high-performance liquid chromatographic (HPLC) procedure is described for the analysis of the chemical sweetener L-aspartyl-L-phenylalanine methyl ester (aspartame). Using a strong cation exchange column and pressures less than 1000 psig, an analysis can be performed in less than 15 min. The technique has been applied to a wide range of food products and formulations. No interferences were found in the samples studied. Recoveries are quantitative, and the coefficients of variation for replicate analyses are less than or equal to 2.5%.


Impurities in commercial saccharin. I. Impurities soluble in organic solvents. Thirteen saccharin samples used for carcinogenicity tests in animals in various laboratories were analyzed for their chemical purity. Although most of the impurities were water-soluble, some were mainly soluble in organic solvents. These impurities were extracted with chloroform-methanol from a water solution of sodium saccharin. Samples obtained as acid-saccharin were converted to the sodium form before extraction. The major impurity in commercial saccharin, o-toluenesulfonamide, was also soluble in this system. Impurities were separated by gas-liquid chromatography of the underivatized, concentrated extract. Eleven major, well separated peaks were collected from the gas chromatographic column and identified by mass spectroscopy. Some of the peaks were compared with known standards. Qualitative and quantitative differences in impurities were observed among different saccharin samples. The identified impurities (in order of appearance from the gas-liquid chromatographic column) were as follows: o-toluenesulfonamide; p-toluenesufonamide; 1,2-benzisothiazole 1,1-dioxide; 1,2-benzisothiazoline 1,1-dioxide; diphenylsulfone; 0,0'-ditolylsulfone; o,m'-ditolylsulfone, o,p'-ditolylsulfone; m,p'-ditolylsulfone; p,p'-ditolylsulfone, and tetracosane.


Evaluation and confirmation of an alkylation-gas-liquid chromatographic method for the determination of carbamate and urea herbicides in foods. An alkylation technique using methyl iodide and sodium hydride in dimethyl sulfoxide has been evaluated for 3 carbamate and 7 urea herbicides in 9 foods. Recoveries ranged from 56 to 113%, depending on herbicide, concentration, and food type. Reproducibility was about +/-6% at 0.1 and 1.0 ppm. Identities of the herbicides were confirmed at these and lower levels by cleaving the aniline moiety from the alkylated herbicides with sodium methoxide in methanol, followed by gas-liquid chromatography on the same column as the parent compound. An electrolytic conductivity detector in the nitrogen mode was used for all analyses. Minimum detectable levels were in the range of 0.005-0.01 ppm in the foods studied.


High-pressure liquid chromatographic analysis of urea herbicides in foods. A method is described for the direct analysis of the urea herbicides linuron, monuron, diuron, chlorbromuron, fluometuron, chloroxuron, and fenuron in cabbage, corn, potatoes, turnip, and wheat at 0.01-1.0 ppm. The samples are extracted with acetone; the filtrate is partitioned with hexane-methylene chloride (1+1) followed by 2 other extractions with methylene chloride. The organic phases are dried and concentrated for column chromatographic cleanup on 2% deactivated Florisil. The column fractions are evaporated just to dryness and redissolved in 10 ml isooctane for high-pressure liquid chromatography on a 25 cm silica gel (5 mum) column. Isopropanol in isooctane is the mobile phase, and compounds are measured by ultraviolet absorption at 254 nm. Recoveries are greater than 80% in most cases. These results are confirmed by alkylation with sodium hydride-methyl iodide in dimethyl sulfoxide to form the methyl products which are analyzed by the same chromatographic system or by gas-liquid chromatography.


Reference Raman spectra of ten phosphorus-containing pesticides. The Raman spectra of malathion, ethion, methyl parathion, parathion, EPN, 0,0-diethyl-0-(2,4-dichlorophenyl) phosphorothioate, dichlorvos, mevinphos, tributyl phosphorotrithioite, and 2,4-dichlorobenzyltributylphosphonium chloride have been recorded. These spectra are presented, along with tables giving values for the frequencies.


Gas-liquid chromatographic determination of chlorphoxim residues in water and fish by in-block methylation. A gas-liquid chromatographic method has been developed for the analysis of residues of chlorphoxim, 2-chloro-alpha ((diethoxyphosphinothioyl)oxy)imino)-benzeneacetonitrile, in water and fish. The method is based on the in-block methylation of chlorphoxim with 0.01M trimethylanilinium hydroxide in methanol. The derivative, O,O-diethyl O-methyl phosphorothioate, was determined quantitatively by using a flame photometric detector specific for phosphorus. The in-block reaction is 70% efficient. Water samples were extracted with hexane; fish were extracted with methylene chloride and cleaned up on an acetonitrile-hexane partition column. Recoveries from water and fish samples spiked with chlorphoxim averaged 86.3 and 80.4%, respectively. Limits of detection were 10.0 ppb for 5 g samples of fish and 0.10 ppb for 300 ml water samples.


Gas-liquid chromatographic determination of azinphos ethyl in human plasma and in mouse plasma, tissue, and fat. A new method for the determination of azinphos ethyl (O,O-diethyl-S-(4-oxo-1,2,3-benzotriazin-3(4H)-ylmethyl) phosphorodithioate) in human plasma and in mouse plasma, tissue, and fat has been developed. The method is based on extraction with benzene or hexane and cleanup of fat and tissue samples by a minicolumn containing Florisil and sodium sulfate. Azinphos ethyl is eluted from the column with 10% acetonitrile in benzene and is concentrated to an appropriate volume for gas-liquid chromatographic analysis, using a 63Ni electron capture detector and a glass column containing 3% OV-1 on Gas-Chrom Q. The method is sensitive to 0.005 ppm in human plasma, 0.01 ppm in mouse plasma, 0.08 ppm in mouse liver, 0.05 ppm in mouse brain, and 0.10 ppm in mouse fat. The limit of detection is 2 pg; mean recoveries ranged from 96 to 98%.


Ion selective electrode for 2,4-dichlorophenoxyacetic acid. An electrode responsive to 2,4-D (2,4-dichlorophenoxyacetic acid) was constructed by dissolving tetrazolium derivatives as an ion exchanger in a liquid membrane. The electrode exhibited rapid and Nernstian response to solutions of 2,4-D over the concentration range 10(-1) to 10(-4)M. The presence of diverse substances such as acetate, benzoate, and 3-indoleacetate showed no appreciable effect on the electromotive force of the electrode.


Improved microbiological procedure for determining bacitracin in premixes and mixed feeds. An improved microbiological procedure is presented for determining bacitracin in premixes and mixed feeds. Premixes are extracted with acidic 50% aqueous methanol, and mixed feeds are extracted with 50% dimethylformamide after washing with acetone to remove fats and pigments. Extracts are diluted with pH 6.0 phosphate buffer and assayed by using a 2-point assay system with Micrococcus flavus as the test organism. The simpler extraction coupled with the 2-point assay system measured bacitracin levels as low as 10 g/ton. Accuracy and repeatability of the 2-point system were at least equivalent to those for official AOAC methods.


Gas-liquid chromatographic determination of chloramphenicol in agricultural crops. A method is presented for the gas-liquid chromatographic determination of chloramphenicol in agricultural crops. Chloramphenicol is extracted with ethyl acetate, cleaned up by silicic acid column chromatography, acetylated with acetic anhydride and pyridine, and then measured by gas-liquid chromatography with electron capture detection. Two stationary phases, DEGS + phosphoric acid and Reoplex 400, were used. The sensitivity was ca 8 ng (40% full scale deflection). The efficicency of the analytical method was evaluated by analyzing crops fortified with chloramphenicol. The average recovery ranged from 72% in unpolished rice to 86% in Chinese radishes.


Colorimetric reagents for determining vitamin A in feeds and foods. Selected blue-color developing reagents for determining vitamin A, effects of some carotenoids, tocopherol, and sterols commonly found in vitamin A extracts of feeds and foods, and effects of moisture and light on the colors developed under normal laboratory conditions were studied. Similar blue colors were obtained using SbCl3, CF3COOH, and CCl3COOH in solutions of CHCl3, CH2Cl2 and C2H4Cl2. In general, the reagents in CH2Cl2 solutions produced the most stable blue colors. The CCl3COOH-in-CH2Cl2 reagent developed slightly higher initial color, but CCl3COOH, especially in CHCl3 solution, was the least stable reagent. Small amounts of moisture affected only SbCl3 reagents, by forming cloudy solutions and precipitates. Carotene and monohydroxy and dihydroxy carotenoids reacted with all reagents tested to produce bluish colors, which, however, reached maximum development much later than the vitamin A blue colors. The presence of sterols slightly decreased color production of vitamin A solutions and frequently slightly increased rate of fading, especially for SbCl3 reagents. With proper precautions any of the reagents studied may be used to determine vitamin A. The preferred reagent for general use probably is CF3COOH-in-CH2Cl2, but it is not the most economical.


Collaborative study of the determination of sodium in dietetic foods by the sodium ion electrode method. The dietetic food sample is diluted with total ionic strength adjusted buffer. The electrode potential of the sample is measured, known increments of sodium are added, and the electrode potential is measured after each addition. The mv readings obtained are plotted on Gran's paper and the concentration of sodium in the sample is found from the intercept of the extrapolated straight line. Seven processed dietetic vegetables and 2 spiked samples were sent to 7 collaborators. There was a 95.8% agreement between the results from the 7 collaborators and the Associate Referee for the unfortified samples. Recoveries of 98.5 and 95.1% were obtained on fortified samples, based on results from 5 collaborators. The statistical analysis indicates minimal bias and adequate precision for determination of sodium in dietetic food at the current regulatory requirements. The method has been adopted as official first action.


Collaborative study of methods for the determination of chloride, citrate, and phosphate in processed cheese. A collaborative study was conducted to compare the International Dairy Federation (IDF)/International Organization for Standardization (ISO)/Association of Official Analytical Chemists (AOAC) proposed methods for the determination of chloride and citrate in processed cheese with the corresponding current AOAC methods. Since there is no current AOAC method for phosphate, only the IDF/ISO/AOAC method was used. Five samples of processed cheese were prepared with varying added amounts of the anions of interest. The samples were analyzed in duplicate by 7 collaborating laboratories. For chloride, both methods are comparable, but since the IDF/ISO/AOAC method is simpler and faster it has been adopted as official first action to replace the current AOAC method, 16.224. For citrate, the colorimetric IDF/ISO/AOAC method is more rapid and simpler than the current AOAC gravimetric method. However, the AOAC method is more precise. Therefore, the proposed method has been adopted as official first action as an alternative to 16.237. For phosphate, 2 of the 7 laboratories were outliers by the Youden ranking test but the results by the remaining laboratories appear satisfactory. The phosphate method should receive further study to reduce the between-laboratory error component.


Spectrophotometric determination of ferric, ferrous, and total iron in drugs by reaction with alpha, alpha'-dipyridyl. The drug sample is dissolved in 0.2N HCl to yield a final concentration of 30 mug Fe/ml, an aliquot is reacted with alpha,alpha-dipyridyl, and the pH is adjusted with an acetate buffer. For Fe(II), the color intensity is measured at 523 nm. For total iron, ascorbic acid is added to a separate aliquot of the sample solution, reducing all the iron present to Fe(II), which is then reacted with alpha,alpha'-dipyridyl, diluted to volume, and read at 523 nm. The Fe(III) content is determined by subtracing Fe(II) from total iron. This method is applicable to iron-containing drugs and drug dosage forms.


Investigation and identification of the bromination products of dimethoxyamphetamines. The qualitative analysis of the aromatic bromination products of the 6 isomeric dimethoxyamphetamines and their hydrochloride or hydrobromide salts is described. Their ultraviolet, mass, and proton magnetic resonance spectra are not sufficiently different for distinction but infrared spectra allow a positive identification to be made and reference spectra are provided for the bromination products of 2,4-, 2,5-, 2,6-, 4,5-, and 3,5-dimethoxyamphetamines. The application of gas-liquid and thin layer chromatography for the analysis of these products is discussed. The bromination of 2,3-dimethoxyamphetamine consistently gave mixtures which could not be separated satisfactorily; spectra are included for completeness of the comparison of products.


Extraction and partition chromatography of tolbutamide as ion-pairs with quaternary ammonium cations. The partition of tolbutamide (1-butyl-3-(p-tolylsulfonyl) urea) as ion-pairs with homologous tetraalkyl ammonium cations was studied. The determination of experimental extraction constants permitted quantitative calculation of distribution ratios, in agreement with theoretical relationships, over a continuous range of about one billion. The nature and the concentration of the counter-ion and solvent composition were the variables studied. Based on the theoretical results, a rapid partition chromatographic procedure was devised. A solution of tolbutamide sample in 10% aqueous tetraethyl ammonium hydroxide is incorporated in the system as the immobile phase in the partition column. A 1+1 mixture of chloroform and isooctane removes extraneous materials; then chloroform elutes the tolbutamide-tetraethyl ammonium ion-pair, which is converted to the free acid by passing the eluate through a phosphoric acid segment, and tolbutamide is determined spectrophotometrically without further treatment. Standard recoveries averaged 100.5+/-0.70%; commercial tablets assayed 100.5+/-0.85%.


Rapid gas-liquid chromatographic method for determining residues of ethephon (2-chloroethyl phosphonic acid) in tomatoes. A rapid method is described for the determination of the growth regulator ethephon (2-chloroethyl phosphonic acid) in tomatoes. Samples are extracted with ethyl acetate. The extract is methylated, decolorized with carbon, and analyzed by gas-liquid chromatography on a column packed with 15% QF-1/10% DC-200 on Chromosorb W (HP). A flame photometric detector is used. Recoveries from tomatoes fortified with 0.1-11.0 ppm ethephon were 78-98%. The sensitivity of this method is about 0.1 ppm.


Gas-liquid chromatographic determination of levamisole residues in bovine milk. A gas-liquid chromatographic (GLC) method is described for determining residues of levamisole, (1-)-(2,3,5,6-tetrahydro-6-phenylimidazo [2,1-b] thiazole), in milk. Levamisole is extracted from an alkaline milk sample with water-saturated ethyl acetate. After co-extractives are removed by various partitionings, the levamisole concentration is measured by GLC by using an alkali (RbSO4) flame ionization detector, vs. an external standard. This method is satisfactory for determining levamisole residues as low as 0.01 ppm in bovine milk. Apparent residues in control milk samples averaged less than 0.001 ppm. Recoveries of 0.01-2.0 ppm added levamisole ranged from 86.5 to 113%. Animals treated with various Tramisol formulations showed apparent levamisole residues below the validated sensitivity of the method (0.01 ppm) at sampling periods exceeding 48 hr.


Bis-diazotized benzidine as a spray reagent for detecting zearalenone on thin layer chromatoplates. Bis-diazotized benzidine is a highly sensitive spray reagent for detecting zearalenone (F-2) in corn samples. As little as 2.0 ng of this Fusarium toxin could be visualized on a thin layer plate after development. In addition, this spray reagent is more specific than the spray reagents currently used for zearalenone.


Determination of sterigmatocystin in corn and oats by gel permeation and high-pressure liquid chromatography. Corn and oats samples are extracted with acetonitrile-water, followed by partition of the extract against hexane, transfer to chloroform, and elution from a silica gel column. The extract is purified by gel permeation chromatography on an automatic instrument. Reverse phase high-pressure liquid chromatography, using a 254 nm ultraviolet detector and 0.1 M KH2PO4-acetonitrile (7+5) as the mobile phase, is used for quantitation. The average recovery from 6 samples of corn to which 0, 25, 50, and 100 mug sterigmatocystin/kg had been added was 59%, with a coefficient of variation of 8.4%. The average recovery from oats fortified at the same levels was 74%, with a coefficient of variation of 12%. A confirmation procedure based on hemiacetal derivative formation on a thin layer chromatographic plate is also described.


Ion selective method for the determination of nitrite in smoked fish. In a direct ion selective electrode method for determining nitrite in smoked fish, the nitrite extracted from the sample is converted to nitrous acid with a measured addition of an acid buffer. The released nitrous acid is measured by a nitrogen oxide electrode. A known addition procedure is used to accurately measure the amount of nitrite in solution and the nitrite concentration is determined directly from Gran's plot paper. Recoveries of nitrite from spiked smoked chub samples ranged from 94.0 to 100.0% with an average of 96.7 and a relative standard deviation of +/-1.9% at the 100 ppm level. Results from the ion selective method were comparable with those from the official first action AOAC method 24.037-24.038.


Oxidative phosphorylation in brown adipose tissue mitochondria from rats kept under normal environmental conditions. Based on criteria such as the ADP/O ratio and respiratory control by ADP, the energy-coupling efficiency of brown adipose tissue mitochondria isolated from rats kept under normal environmental conditions for a long time decreased remarkably. The presence of bovine serum albumin, GTP, or ATP plus carnitine in the reaction medium markedly increased the efficiency of oxidative phosphorylation of brown adipose tissue mitochondria. Pre-treatment of brown adipose tissue mitochondria with 2% bovine serum albumin, GTP, or ATP plus carnitine caused a decrease in the amount of free fatty acids bound to the mitochondria from 13.1 to 7.0, 9.0, or 8.2 mug per mg protein, respectively. Removal of the free fatty acids by means of these pre-treatments resulted in restoration of efficient oxidative phosphorylation; there was a correlation between the amount of free fatty acids removed and the degree of recovery in the respiratory control ratio. The elimination of only a fraction of the free fatty acids, as little as 4 mug per mg protein, was sufficient to ensure respiratory control by ADP. It appears that the free fatty acids which lie mainly outside the inner mitochondrial membrane are responsible for the decrease in the efficiency of oxidative phosphorylation in brown adipose tissue mitochondria isolated from rats kept under normal environmental conditions.


Enzyme immunoassay of testosterone using the testosterone-glucoamylase complex. A highly sensitive, reproducible method was established for enzyme-coupled immunoassay of testosterone, involving coupling of testosterone to glucoamylase [EC 3.2.1.3] with a water-soluble coupling reagen carbodimide. No enzyme activity was lost during this coupling procedure. The sensitivity of the method was comparable to that of competitive protein binding assay.


Further studies on the specificity of the minor ribonuclease from Aspergillus saitoi. In order to investigate the base specificity of the minor RNase [EC 3.1.4.23] from Aspergillus saitoi, the kinetic constant of the enzyme was measured with 16 dinucleoside phosphates (XpY's) as substrates at pH 5.5 and 25 degrees. The maximum rates of transesterification of GpY's were in the range of 10,000 to 2,800 and were markedly larger than those of other XpY's, including XpG's. The average Km values of UpY, CpY, ApY, and GpY increased in the order A, C, U, and G. This order coincides with that of the rates of release of 4 common nucleotides from RNA by RNase Ms (the rates decreased in the order 3'-GMP, 3'-AMP, 3'-CMP, and 3'-UMP), except for the case of GpY. Therefore the rates of release of nucleotides seem to be dependent on the affinity constant of the X base in XpY, except in the case of GpY. The high rate of release of guanylic acid from RNA was explained by the findings that higher rates of hydrolysis of GpY's compensate for their lower affinity to the enzyme. These results suggested that the base specificity was rather dependent upon the X nucleotide in XpY. The Ki values of various nucleotides and nucleosides towards RNase Ms were measured. These compounds inhibited the RNase competitively. Although the inhibitory effect depends on the bases, sugars and location of phosphate, when the location of phosphate on the sugar was the same, the Ki values of ribonucleotides decreased in the order U, G, C, and A and those of deoxyribonucleotides decreased in the order T, G, C, and A. The dependence of the inhibitory effect of ribonucleosides on the bases was similar to that of ribonucleotides, but that of deoxyribonucleosides was in the order dT, dA, dG, and dC.


Identification of glucosyl sphingosine from Gaucher's spleen by gas chromatography-electron impact and GC-chemical ionization mass spectrometry. Glucosyl sphingosine was isolated from the spleen of a patient with adult-type Gaucher's disease. The yield of purified glucosyl sphingosine was 9.3 nmoles/g wet tissue. The gas chromatography-chemical ionization mass spectrum of acetylated glucosyl sphingosine showed peaks due to the presence of ions formed by successive loss of acetic acid (mass 60) from the molecular ion (QM+, 714). Fragments from acetylated sugar, m/e 331, and from the sphingosine residue, m/e 306, were also detected. The GC-CI mass spectrum of the trimethylsilyl derivative of glucosyl sphingosine showed peaks due to the molecular ion (QM+, 822), ions from the sugar moiety (m/e 361, 271), and ions from the sphingosine base (m/e 264, 280). Fragmentation analysis of the purified sample by GC-EI and GC-CI mass spectrometry confirmed the structure glucopyranosyl(1 leads to 1)-1,3-dihydroxy-2-amino-4-octadecene.


Additional evidence for hydrophobic bond formation in the adsorption of sulfanilamide on bio-gel beads. We have previously suggested the involvement of both hydrogen binding and hydrophobic bonding in the adsorption of sulfanilamide on Bio-Gel beads. In the present study, we closely examined the concentration dependence of the binding curve and our proposed binding model has been corroborated. For comparison, binding parameters and thermodynamic data pertaining to the sulfanilamide-Sephadex system have been also evaluated.


The clinic waiting room. Environment for health education via television. Parents and children in a clinic waiting room are motivated toward better health and constitute a receptive audience for health education via the familiar medium of television. A videotape cassette covering materials from four areas of child health care was displayed in an out-patient waiting area, using a recorder-player and monitor. Parents were interviewed prior to the introduction of the video program, immediately after the program, and again by telephone two weeks after exposure to the program. Analysis of the interviews revealed increases in knowledge about child health, as well as positive attitudes toward the clinic. The familiarity, availability, and nonthreatening nature of the medium were deemed advantages of this format.