Synovial osteochondromatosis: a histopathological study of thirty cases. In thirty cases of synovial osteochondromatosis studied clinically and pathologically, the process appeared to follow a temporal sequence characterized by three recognizable phases (1) active intrasynovial disease only, with no loose bodies; (2) transitional lesions with both active intrasynovial proliferation and free loose bodies; and (3) multiple free osteochondral bodies with no demonstrable intrasynovial disease. If gross examination at the time of surgery shows that the disease is in the third phase, it would appear that synovectomy may not be necessary. However, extrasynovial intra-articular cartilaginous lesions may persist after synovectomy in the other two phases and may grow, causing recurrence of clinical symptoms in the absence of new intrasynovial disease.


Membranous lipodystrophy: a clinicopathological study of six cases. Membranous lipodystrophy apparently is a new disease, first reported and named by Nasu and associates 31 in 1971. We have collected six cases of this disease. The initial manifestation was articular pain at adolescence. Symmetrical changes in the bones of the extremities then appeared and the disease seemed to progress slowly with age. The younger patients exhibited only skeletal pain or fractures, while the older patients had some neuropsychiatric changes. Three of the patients died in middle age. The cystic bone lesions contained a yellow, lipid-like substance which histologically showed a characteristic membranocystic appearance. Electron microscopic study showed unique features, but biochemical analysis of the substance did not reveal a definable abnormality.


Bone grafts with microvascular anastomoses of vascular pedicles: an experimental study in dogs. Using microvascular anastomoses of artery and vein, bone grafts with vascular pedicles from the rib were transferred to inlay and bridge defects in the femora of forty-two dogs. The osteocytes of the pedicle graft were not affected, and neither necrosis nor creeping substitution occurred in the grafted bone. The pedicle bone grafts united to the recipient bed earlier than did the non-pedicle bone grafts, and the rate of non-union of the pedicle bone grafts was lower than that of the non-pedicle grafts.


Congenital vertical talus: treatment by open reduction and navicular excision. Twelve patients with sixteen feet showing true congenital vertical talus were treated at Children's Hospital of Pittsburgh by excision of the navicular as an adjunct to open reduction. When these children were evaluated two to fifteen years after naviculectomy, all were asymptomatic and fully active. Except for one Achilles-tendon lengthening (three months after naviculectomy), none had required further surgical procedures. Fifteen feet were examined in detail. Assessed on an anatomical basis, three of the feet were excellent; seven, good; four, fair; and one, poor. The best results were obtained in the patients who were eighteen months old or younger at the time of operation.


Deep wound sepsis following total hip arthroplasty. After follow-ups ranging from two to five years on all but four (five hips) of 2,694 patients who had 3,215 total hip arthroplasties, deep wound infection had been demonstrated in forty-two hips (1.3 per cent). The infections among the 3,210 hips appeared during the immediate postoperative period or as long as five years after surgery. All operations were performed in conventional operating rooms. Previous operations, prolonged operating time, positive culture at operation, and unrecognized preoperative sepsis were related to the development of deep infection. In only eight of the forty-one patients (forty-two hips) was salvage of the prosthetic arthroplasty possible. The deaths of tree patients were directly attributable to the infection or its treatment.


The penetration characteristics of cefazolin, cephalothin, and cephradine into bone in patients undergoing total hip replacement. Preoperatively, to prevent infection, seventy-one patients who were to have total hip arthroplasty were given one gram of cephalothin, cephradine, or cefazolin intravenously. Simultaneous samples of bone and serum were obtained after various time intervals and assayed for cephalosporin concentration to correlate the antibiotic concentrations in these sites with time. Of the cephalosporins tested, cefazolin achieved the highest total peak levels in bone (thirty micrograms per gram), followed in descending order by cephradine (twenty-three micrograms per gram) and cephalothin (2.8 micrograms per gram). These peak levels in bone, reached twenty-five to forty minutes after injection, were sixty, 6.7, and fifteen times higher than the usual mean minimum inhibitory concentrations of cefazolin, cephradine, and cephalothin, respectively, for penicillin-resistant staphylococci. The half-lives of the antibiotics in bone were forty-two, forty, and thirty minutes, respectively.


Metal sensitivity before and after total hip arthroplasty. Of 212 patients undergoing total hip replacement who were tested preoperatively for sensitivity to nickel, chromium, and cobalt, fourteen showed sensitivity. No sensitivity to the bone cement was recorded. Of 173 patients who had never had a metal implant before, 5.8 per cent showed a positive reaction. Two patients out of fifteen with a failed McKee-Farrar prosthesis were found to be sensitive. Of six patients who had a stable McKee-Farrar prosthesis in the other hip, none showed sensitivity to the metal. In four of sixty-six patients, sensitivity to nickel or cobalt developed after the implantation of a metal-to-plastic prosthesis. No patients were sensitized to the cement. The consequences of proved hypersensitivity in patients with metal-to-plastic prostheses, either present prior to insertion of the prosthesis or evoked by the implant material, are not known.


Methylmethacrylate as an adjunct in spinal instrumentation. Sixteen patients with scoliosis were treated with Harrington-rod instrumentation supplemented by methylmethacrylate fixation at the distraction sites to reduce the possibility of dislodgement of a hook due to inferior bone stock or the patients' inability to cooperate postoperatively because of mental insufficiency or involuntary-movement disorders. Follow-up ranged from six to thirty-eight months (average, fourteen and one-half months). There were no complications related to the use of methylmethacrylate in these patients.


Scintigraphic findings in stress fractures. Forty-two patients suspected of having stress fractures were evaluated by serial roentgenograms and by one total-body scan with detailed views of suspicious areas. Stress fracture was the ultimate clinical diagnosis in twenty-one patients, and in fifteen of them the roentgenograms were normal while the scintigram was positive. The false negative rate for the roentgenograms was 71 per cent. In eleven of the fifteen patients, the roentgenograms eventually became positive. There were five positive scintigrams from causes other than stress fracture, giving a false positive rate for scintigraphy of 24 per cent. The bones with stress fractures included the metatarsals, calcaneus, tibia, femur, and fibula.


Blood alcohol and fat embolism syndrome. In an analysis of the cases of 100 consecutive patients with diaphyseal fractures in the major bones of the lower limb, the incidence of fat embolism syndrome was 17 per cent. The blood alcohol level was determined at the time of admission. A raised level of alcohol in the blood was associated with a lower incidence of fat embolism.


Kienböck's disease: the role of silicone replacement arthroplasty. A review of thirty-eight patients with Kienböck's disease indicated that both delay in diagnosis and prolonged treatment by plaster immobilization led to progressive collapse of the lunate and an unsatisfactory result in most instances. Four clinical and roentgenographic stages were identified, and the results of silicone replacement arthroplasty were correlated with the preoperative stage after an average follow-up of twenty-seven months. The results were satisfactory in fourteen of twenty wrists in which the procedure was performed before collapse of the lunate had occurred. The importance of early diagnosis and early surgical treatment of this disorder was emphasized by the findings in this study.


The use of paratenon, polyethylene film, or silastic sheeting to prevent restricting adhesions to tendons in the hand. We treated 132 patients by insertion of paratenon, polyethylene, or Silastic between a digital tendon and a bone, ligament, or fixed fascial structure to prevent adhesions. From 1950 to 1974, autogenous paratenon was used in thirty patients; from 1956 to 1965, polyethylene film was used in sixty-three patients; and from 1965 to 1974, Silastic sheeting was used in thirty-nine patients. By comparing the preoperative and postoperative measurements of joint motion and the changes in the distance separating the pulp of a finger from the palm during flexion, these patients were calssified as improved, unchanged, or worse. In some areas the material used appeared to make little difference, but in other areas one or the other was superior. Silastic sheeting (non-reinforced) proved to be the best material for most conditions, but it should not be employed when the skin is of poor quality or beneath a pedicle flap, and it should not be used adjacent to a tendon graft in an area that has recovered from an infection. Under those circumstances, paratenon is the preferred material.


Percutaneous fixation of supracondylar fractures of the humerus in children. Of 1,118 supracondylar fractures of the humerus in children treated over a six-year period, 189 are described with a follow-up of more than two years. These patients were treated with closed reduction and percutaneous fixation of the fragments with two wires. Eighty-five per cent of the final results were satisfactory.


Cast-bracing for fractures of the femur. A preliminary report of a modified device. The second-generation cast-brace system offers some advantages over previous systems of cast-brace treatment for fractures of the femur. Because the thigh section is adjustable, loosening of the cast-brace is not a problem. The device can be applied earlier and need not be reapplied when the girth of the thigh is reduced. Using a roller traction system, the cast-brace can also be used initially for traction and suspension without the complexity of traditional systems. With the use of commercially available plastic knee joints, special skills in alignment of the joints are not necessary, and no specially trained personnel need be on hand. The lightweight thigh section coupled to custom-fit plaster leg section, with the foot and ankle free, are less bulky than a totally plaster cast-brace with metal side joints. Walking may be begun earlier with the device, and in-patient hospital time is reduced. However, this system requires a high level of patient cooperation in that the patient is free to adjust the system himself and, therefore, the system may not be safe for application in all settings.


The popliteus muscle.

The popliteus muscle. The popliteus muscle was studied during both normal gait and a series of planned exercises. Its activity during the walking cycle was shown to begin shortly before heel-strike and to continue throughout three-quarters of the stance phase. During the exercises the muscle was active during internal rotation of the tibia on the femur, and during normal gait the phasic activity of the popliteus coincided with internal rotation of the tibia on the femur. It was concluded that the basic function of the popliteus is to help to bring about and maintain internal rotation of the tibia on the femur.


Tibial rotation-plasty for proximal femoral focal deficiency. The most common treatment for proximal femoral focal deficiency is amputation at the level of the ankle joint and subsequent prosthetic fitting in the manner used for an above-the-knee amputee. Since 1967, five patients with proximal femoral focal deficiency were treated with the Van Nes procedure -- an 180-degree tibial rotation-plasty to convert the ankle joint to a knee joint. Two of the five patients had excellent results -- the tibial rotation-plasty allowed the ankle joint to function as a knee joint with 90 degrees of flexion and placed it at the level of the contralateral anatomical knee. Fusion of the anatomical knee above the tibial rotation-plasty in these two patients provided a stable tibiofemoral lever arm that functioned as the thigh. Two patients had good results -- satisfactory functional and cosmetic improvement. In the remaining patient, who had associated paraxial fibular hemimelia with absence of the fourth and fifth rays of the foot, the result was a failure.


Fragmentation of the distal pole of the patella in spastic cerebral palsy. Of eighty-five consecutive patients, thirteen to twenty years old, with spastic cerebral palsy involving one or both extremities (thirty-five patients seen at one institution and fifty, at another), four had roentgenographic evidence of fragmentation of the distal pole of the patella. In addition, three other patients with six spastic lower extremities, four of them with patellar fragmentation, were also included. In these seven patients, there were nine knees with patellar fragmentation, twelve knees with patella alta, nine with a flexion contracture, five that were painful, and four with changes in the tibial tubercle resembling those found in Osgood-Schlatter disease. Excessive tension in the quadriceps mechanism, usually in the presence of a flexion contracture, appeared to cause the lesions. Four of the fragmented patellae healed after hamstring release and correction of the flexion deformity.


Fractures of the atlas associated with fractures of the odontoid process and transverse ligament ruptures. One case of fracture of the atlas associated with rupture of the transverse ligament and three cases of atlantal fracture with associated fractures of the odontoid process are reported. In such cases, halo immobilization is recommended until the atlantal fracture has healed, followed by atlanto-axial fusion for instability of the cervical spine.


Fracture of the odontoid process in young children. Fracture of the odontoid process in young children is possibly not as rare as hitherto believed. In this paper, two more patients with this fracture are presented, and an important diagnostic clinical sign is described. Both patients sustained the injury by falling from heights no greater than sixty-one to ninety-one centimeters. In each instance, injury to the cervical spine was suspected but initial roentgenograms failed to reveal any fracture. The patients were quite comfortable when lying supine and when fully erect. Each child strongly resisted any attempt at extension of the neck and cried bitterly when brought to either the erect or the recumbent position unless the head was passively supported. This a valuable clinical sign when injury to the odontoid process is suspected. Subsequent roentgenograms confirmed the diagnosis in each instance.


Roentgenographic measurements after Müller total hip replacement. Correlations among roentgenographic measurements and hip strength and mobility. In fifty-two patients with Müller total hip replacement, roentgenographic measurements of prosthetic component positioning were correlated with hip-muscle strength and mobility measurements. Compared with the normal side, the average position of the center of the prosthetic head was more medial and superior in the pelvis, and the greater trochanter was more distal and lateral. Increasing neck length (distance from the center of the prosthetic head to the lesser trochanter) and a more distal position of the greater trochanter were among the measurements that related favorably to measurements of patient function. More superior placement of the center of the prosthetic head in the pelvis was associated with a more superior position of the lesser trochanter, which related adversely to function.


Interrelationships between water and cellular metabolism in Artemia cysts. VII. Free amino acids. The concentration of total ninhydrin-positive material (NPM) soluble in 5% trichloroacetic acid was measured in cysts of the brine shrimp. Artemia salina, as a function of hydration level. No net change in NPM was observed until the cysts had achieved a water content of about 0.65 g H2O/g of initially dry cysts. Above this hydration threshold the NPM content increased markedly. Examination of the free amino acid composition of cysts incubated at selected hydration levels revealed that almost all of the amino acids underwent net change above the hydration threshold. However, just below this threshold, the free amino acid composition was essentially the same as in fully dried cysts. The activity generating net changes in the concentration of free amino acids above the hydration threshold was shown to be metabolic in nature and restricted to the cellular component of the cyst.


Human fibroblast conditioned media contains growth-promoting activities for low density cells. Normal diploid human fibroblasts, cultured at high density (1-2 X 10(5) cells per cm2) release two growth promoting activities into the culture medium. The fibroblast proliferation activity-conditioned medium facilitates the attachment of low density cells to the substrate. The activity resides in a non-dialyzable material that is sensitive to proteolytic inactivation. A second activity is dialyzable and can be recovered in the dialysate. In the presence of serum it stimulates cell growth. After 168 hours of incubation conditioned medium cultures contain five times more cells than are present in comparable cultures without conditioned medium. A reproducible biological assay for each activity is described.


Relationship of heat labile glucose-6-phosphate dehydrogenase and multiple molecular forms of the enzyme in senescent human fibroblasts. Human fibroblasts derived from newborn foreskin and designated CF-3 were assayed for heat labile glucose-6-phosphate dehydrogenase (G6PD) when they had grown to confluency, as well as when they were arrested in an essentially nonmitotic state. Under both culture conditions there was an increase in heat labile G6PD (up to 25% of the total activity) as cells progressed through their in vitro lifespan; however, arrested cells exhibited less heat labile G6PD than did comparable growth controls (5-10% decrease). Acrylamide gel electrophoresis of crude G6PD preparations revealed three distinct bands of enzymatic activity. One of the bands was tentatively identified as the dimeric form of the enzyme and another as the tetrameric form. The tetrameric form was more heat sensitive, and the percent of the total activity of this form increased as the cells became senescent. The percent of total activity of the tetrameric form was comparable to the percent heat labile enzyme assayed at a given population doubling level. These results indicated that the observed increase in heat lability of G6PD with age may be due to a shift in equilibrium to the tetrameric form of the enzyme rather than the synthesis of aberrant enzyme molecules.


Persistence of serum antibody to hepatitis B core antigen. The purpose of the present study was to measure the amount of antibody to hepatitis B core antigen (anti-HBc) in different populations by the immunoelectroosmophoresis method. High titers of anti-HBc, up to 1/4,096, were found in the acute stage of hepatitis B virus infections and in the chronic carrier state of hepatitis B surface antigen. In cases of acute hepatitis the anti-HBc titers gradually declined to low levels but persisted for the observation time of 5 to 6 years. Individuals positive for antibodies to hepatitis B surface and core antigens selected from a Swedish "normal" population showed still lower anti-HBc titers, indicating that the hepatitis B infection had occurred earlier. The anti-HBc titers in sera drawn at intervals of 4 years from a group of hemophilia patients may indicate previous infection with replicating hepatitis B virus rather than immunization with noninfectious hepatitis B core antigen material.


Teichoic acids in pathogenic Staphylococcus aureus. Twenty-six strains of Staphylococcus aureus obtained from patients with endocarditis were studied for the production of alpha- and/or beta-ribitol teichoic acid (TA), using highly specific anti-TA antibodies prepared in rabbits. A counterimmunoelectrophoretic assay was used. Beta-TA was the predominant residue produced by all strains; alpha-TA was found in all strains, but in smaller amounts and with much strain-to-strain variations. Antibodies in patients' sera were found against beta-TA in higher titers and for longer periods than were anti-alpha-TA antibodies. Antibodies against one or both TA residues were present in all but one of 26 patients.


Reactivity and specificity of Trichinella spiralis fractions in cutaneous and serological tests. Six diethylaminoethyl-cellulose fractions of a larval Trichinella spiralis extract, an Ascaris suum extract, and a nonrelated protein were used for cutaneous tests in guinea pigs with 8-, 14-, and 73-day-old T. spiralis infections, in guinea pigs with 13-day-old A. suum infections, and in normal guinea pigs. A selected T. spiralis fraction was used in hemagglutination (HA) tests with sera of 8 T. spiralis-infected rabbits, 41 sera of trichinellosis patients positive by bentonite agglutination tests, and 50 sera of clinically healthy persons. Immediate-type cutaneous reactions revealed extensive cross-reactivity between both parasites, although the establishment of conventional limits for considering a reaction positive allowed the specific diagnosis of acute or chronic trichinellosis with different fractions. Delayed-type reactions were specific with all fractions except one, and different fractions reacted during either the acute or the chronic phase of trichinellosis. HA detected anti-Trichinella antibodies in all the rabbits 9 to 10 days postinfection, in all trichinellosis patients, and in none of the healthy people. Correlation between HA and bentonite agglutination titers and other considerations suggest that HA with the selected fraction detects early antibodies. HA inhibition tests with A. suum extract suggest lack of HA cross-reactivity between the A. suum- and T. spiralis-selected fractions. The use of different fractions in diverse tests for clinical or epidemiological studies is suggested.


Selective medium for isolation of Bacteroides nodosus. The sensitivity of Bacteroides nodosus, the causative agent of sheep foot rot, to 24 selected antimicrobial agents was tested. Many contaminants ordinarily associated with foot rot lesions were sensitive to lincomycin, whereas B. nodosus demonstrated resistance to this antibiotic. A concentration of 1 microgram of lincomycin per ml of basal medium optimally inhibited contaminants while allowing growth of B. nodosus. The basal medium was Eugon agar with 0.2% yeast extract and 10.0% defibrinated horse blood. Parallel inoculations of 31 foot rot lesion specimens onto basal medium and basal medium containing lincomycin (selective medium) were performed. B. nodosus was isolated from 16 of the specimens cultured on the selective medium and from only 3 of the specimens cultured on the basal medium. The concentration of agar in the standard Eugon medium was found to influence the growth of B. nodosus in the presence of lincomycin. Trimethoprim also exhibited potential selectivity for B. nodosus.


The number of glycine residues which limits intact absorption of glycine oligopeptides in human jejunum. Studies were performed to determine whether glycine peptides of four or more glycine residues can be transported by the peptide carrier system, previously shown to transport diglycine and triglycine. When human jejunum was perfused with tetraglycine solutions, the rate of tetraglycine disappearance increased linearly as the concentration was increased over the range of 12.5-50 mM, however, the rate was slow in comparison to diglycine and triglycine disappearance rates.Glycylleucine, a competitive inhibitor of diglycine and triglycine transport, was without effect on the disappearance rate of tetraglycine, but increased (over sixfold) appearance rates of triglycine and diglycine (products of tetraglycine hydrolysis). These products were the results of hydrolysis of tetraglycine by the brush border enzymes because cytosol fraction lacked any hydrolase activity against tetraglycine. When a jejunal ring preparation was incubated with tetraglycine, there was intracellular accumulation of diglycine and triglycine but not of tetraglycine. The rates of glycine uptake were always markedly greater from diglycine and triglycine solutions than from corresponding glycine or tetraglycine solutions; rates of glycine uptake from tetraglycine solutions were either similar to or greater than rates from glycine solutions, depending on the infusion concentration. When the number of glycine residues was increased to hexaglycine, the phenomenon of a greater rate of glycine uptake from a peptide versus a free amino acid solution was no longer apparent. In vitro assay of peptide hydrolase activity of the luminal fluid revealed no activity against diglycine and triglycine and only trace activities against tetraglycine, pentaglycine, and hexaglycine. THE ABOVE OBSERVATIONS SUGGEST THE FOLLOWING CONCLUSIONS: (a) the disappearance of tetraglycine in the human jejunum is accomplished principally by hydrolysis by brush border oligopeptidases; (b) the rate limiting step in the uptake of glycine from tetraglycine or higher peptides is due to hydrolysis of these peptides to absorbable products.


Comparison of aryl hydrocarbon hydroxylase induction in cultured blood lymphocytes and pulmonary macrophages. Aryl hydrocarbon hydroxylase induction was studied in cultured peripheral blood lymphocytes and pulmonary alveolar macrophages from 15 smokers and 8 nonsmokers with a variety of pulmonary diseases. Enzyme levels in lymphocytes from cigarette smokers cultured in medium without an inducing agent were 57+/-6 mU/10(6) cells (mean+/-SEM), while enzyme levels in lymphocytes from nonsmokers were 20+/-2 mU/10(6) cells (P < 0.001). When lymphocytes were cultured in the presence of the inducing agent, benzo-(a)anthracene, enzyme activity was increased to 168+/-23 mU/10(6) cells in smokers' cells and 99+/-22 mU/10(6) cells in lymphocytes from nonsmokers (P < 0.04). When noninduced enzyme values in cultured macrophages were compared, smokers' cells had enzyme levels of 45+/-5 mU/10(6) cells, whereas nonsmokers had enzyme activity of 24+/-2 mU/10(6) cells (P < 0.002). However, pulmonary macrophages from smokers or nonsmokers, cultured in the presence of benzo(a)-anthracene, had similar levels of induced enzyme activity (P > 0.1). A positive correlation was observed for nonsmokers (r = 0.596, P > 0.1 <0.2) or smokers (r = 0.640, P < 0.04), when enzyme values for noninduced cultures of macrophages and lymphocytes from individual patients were simultaneously compared. Enzyme values for macrophages and lymphocytes cultured in the presence of an inducer also revealed a positive correlation for individual smokers (r = 0.801, P < 0.001) or nonsmokers (r = 0.785, P < 0.01). Inducibility (expressed as fold-induction) for macrophages and lymphocytes from individual patients was also positively correlated (r = 0.889, P < 0.001 for nonsmokers and r = 0.942, P < 0.001 for smokers). These results indicate that the capacity for aryl hydrocarbon hydroxylase induction is similar whether tested in lymphocytes or pulmonary macrophages from this group of pulmonary disease patients.


Osteomalacia due to 1alpha,25-dihydroxycholecalciferol deficiency. Association with a giant cell tumor of bone. Oncogenic osteomalacia is a syndrome in which unexplained osteomalacia remits after resection of a coexisting mesenchymal tumor. We have investigated the mechanism by which a giant cell tumor of bone caused biopsy-proved osteomalacia in a 42-yr-old woman. The biochemical abnormalities were: hypophosphatemia; decreased renal tubular maximum for the reabsorption of phosphate per liter of glomerular filtrate; negative calcium and phosphorus balance; hyperaminoaciduria; and subnormal calcemic response to exogenously administered parathyroid hormone. Malabsorption, hypophosphatasia, fluorosis, and acidosis were excluded as causes of the osteomalacia. Serum 25-hydroxycholecalciferol was normal (27+/-1 ng/ml). However, the serum concentration of 1alpha,25-dihydroxycholecalciferol was low (1.6+/-0.1 ng/100 ml). Oral administration of physiological amounts of 1alpha,25-dihydroxycholecalciferol resulted in resolution of the biochemical abnormalities of the syndrome and healing of the bone pathology. We suggest that tumor-induced inhibition of 1alpha,25-dihydroxycholecalciferol synthesis caused the osteomalacia. The causal role of the tumor was proved by demonstrating that resection was accompanied by roentgenographic evidence of bone healing and maintenance of normal serum phosphorus; renal tubular maximum for the reabsorption of phosphate; calcium and phosphorus balance; aminoaciduria; and calcemic response to exogenous parathyroid hormone.


The properties of immune complexes formed by human antibodies to factor VIII. Although human antibodies to Factor VIII inactivate its procoagulant activity, they do not form immunoprecipitates when tested with this antigen. To understand this observation, we have examined the interaction of normal human Factor VIII with four high-titer human anti-Factor VIII, two from transfused hemophiliacs and two "spontaneous" antibodies from nonhemophilic individuals. An estimate of the size of complexes formed by these antibodies has been obtained by agarose gel filtration of mixtures of anti-Factor VIII with cryoprecipitate. Complexed anti-Factor VIII was detected by the method of Allain and Frommel: acid dissociation of complexes at pH 3.5. Complexed anti-Factor VIII was detected in column fractions eluting between the void volume and those which correspond to the elution volume of human IgG. In contrast, Factor VIII procoagulant activity was restricted to void volume fractions when separations were carried out in antigen excess, and free anti-Factor VIII was limited to late-eluting fractions when separations were carried out in antibody excess. A small proportion of the complexed anti-Factor VIII was present in void volume fractions; the quantity was directly related to the ratio of antibody to antigen.Thus, although some complexed anti-Factor VIII is detected in void volume fractions, as would be expected for complexes formed with a very large plasma protein, most immune complexes elute in fractions that indicate interaction with a smaller antigen. These findings suggest that human anti-Factor VIII inactivates procoagulant activity by forming a complex with a small, apparently univalent, component of Factor VIII. This property may prevent immunoprecipitate formation.


Inheritance of low immunoreactive human plasma dopamine-beta-hydroxylase. Radioimmunoassay studies. Inheritance plays an important role in the determination of human plasma dopamine-beta-hydroxylase (DBH) enzymatic activity. It has been demonstrated that an allele (d) for very low enzymatic plasma DBH is inherited as an autosomal recessive trait. A radioimmunoassay for human DBH was developed to test the hypothesis that the presence of this allele results in a decrease in plasma DBH protein levels. The mean immunoreactive DBH (IDBH) in blood from a randomly selected population of adolescents was 824+/-38 ng/ml (mean+/-SEM, n = 134). The correlation coefficient of enzymatic DBH with IDBH for this group of 134 adolescents was 0.84 (P < 0.001). Of these subjects, 3.7% had values of < 100 ng/ml and appeared to compose a separate subgroup analogous to the 3-4% of the population that is homozygous for the allele for low enzymatic activity. There was a significant sibling-sibling correlation of IDBH values in the 14 sibling pairs included among the 134 subjects studied (r = 0.60, P < 0.025). IDBH was also measured in blood from 56 subjects homozygous (dd) for the allele for low enzymatic DBH (enzymatic activity < 50 U/ml) and in blood of 80 first-degree relatives of homozygous probands. All but two dd subjects had IDBH levels of <100 ng/ml. Results of family studies were compatible with the autosomal recessive inheritance of an allele for IDBH levels of less than 100 ng/ml which segregates with the allele for very low enzymatic activity. Average IDBH in blood of 37 obligate heterozygotes as determined by family studies (Dd) was 599+/-53 ng/ml (mean +/- SEM), significantly lower than the IDBH values found in a randomly selected population (P < 0.005). These results are compatible with the conclusion that the presence of the allele for low plasma enzymatic DBH results in a decrease in the quantity of DBH protein in human plasma.


Phosphohexosyl recognition is a general characteristic of pinocytosis of lysosomal glycosidases by human fibroblasts. We recently presented data showing that mannose-6-phosphate was a potent competitive inhibitor of pinocytosis of human platelet beta-glucuronidase, and that treatment of "high-uptake" forms of the enzyme with alkaline phosphatase destroyed the high-uptake property of the enzyme without diminishing its catalytic activity. These data indicate that phosphate is a necessary component of the recognition marker on the enzyme for pinocytosis by human fibroblasts, and suggest that the phosphate on high-uptake forms of the enzyme is present as a phosphohexosyl moiety. Results presented here show that mannose-6-phosphate is also a potent inhibitor of pinocytosis of the following enzyme preparations: (a) beta-glucuronidase from human spleen, liver, placenta, and urine; (b) beta-hexosaminidase and beta-galactosidase from human platelets; (c) beta-hexosaminidase from human fibroblast secretions. Alkaline phosphatase treatment of all these enzymes except beta-galactosidase, which was unstable to the incubation conditions and could not be tested, greatly diminished the uptake activity of the enzymes without diminishing their catalytic activity. These results suggest that phosphohexosyl recognition is a general characteristic of pinocytosis of lysosomal glycosidases.


Effects of autoantibodies to the insulin receptor on isolated adipocytes. Studies of insulin binding and insulin action. Autoantibodies to the insulin receptor have been detected in the sera of several patients with the Type B syndrome of insulin resistance and acanthosis nigricans. In this study we have used three of these sera (B-1, B-2, and B-3) as probes of the insulin receptor in isolated rat adipocytes. Preincubation of adipocytes with each of the three sera resulted in an inhibition of subsequent [(125)I]insulin binding. 50% inhibition of binding occurred with serum dilutions of 1:5 to 1:7,500. As in our previous studies with other tissues, Scatchard analysis of the insulin-binding data was curvilinear consistent with negative cooperativity. Computer analysis suggested that in each case the inhibition of binding was due to a decrease in receptor affinity rather than a change in available receptor number. In addition to the effects on insulin binding, adipocytes pretreated with antireceptor sera also showed alterations in biological responses. All three sera produced some stimulation of basal glucose oxidation. With serum B-3, maximal stimulation of glucose oxidation occurred at a serum concentration that inhibited binding by only 10-15%, whereas with serum B-2 the dilution curves for inhibition of binding and stimulation of glucose oxidation were superimposable. Serum B-1 behaved as a partial agonist; that is, it inhibited binding more effectively than it stimulated glucose oxidation. Cells pretreated with this serum in a concentration which inhibited binding by 80% also showed a five-fold shift to the right in the dose response of insulin-stimulated glucose oxidation, whereas spermine-stimulated glucose oxidation was unaffected. Serum B-2, which contained the highest titer of antireceptor antibodies, also stimulated 2-deoxy-glucose transport, as well as glucose incorporation into lipid and glycogen. Both the ability of the serum to inhibit binding and stimulate glucose utilization were enriched in purified immunoglobulin fractions and retained in the F(ab')(2) fragment of the IgG. In addition, the bioactivity was blocked by antihuman IgG but not by anti-insulin antibodies. Enzymatic digestion of adipocytes with trypsin resulted in a complete loss of insulin-stimulated bioactivity of serum B-3, but had only minor effects on the glucose oxidation produced by serum B-1 or B-2.These data suggest that the antibodies present in these three sera bind to different determinants on the insulin receptor. Thus, these antibodies may be useful probes of receptor structure and function.


Lung fluid dynamics in awake newborn lambs. We measured steady-state lung lymph flow, lymph protein flow, and simultaneous pulmonary vascular pressures in 12 1-wk-old unanesthetized lambs and compared these measurements to those of previous studies, performed under similar conditions, on nine awake adult sheep. The purpose of these experiments was to compare newborn and adult sheep with respect to transvascular filtration of fluid and microvascular permeability to plasma proteins. We prepared the lambs surgically to isolate and collect lung lymph and measure average pulmonary arterial and left atrial pressures, allowing at least 2 days for the lambs to recover from surgery before studies began. Lambs had higher pulmonary arterial and left atrial pressures, lower lymph and plasma protein concentrations, and 57% more lymph flow per gram of dry bloodless lung than sheep; the difference in protein flow between lambs and sheep was not significant. Protein concentration in lymph relative to that in plasma was significantly lower in lambs than in sheep; but the ratio of albumin concentration to globulin concentration in both lymph and plasma was almost identical in the two groups of animals. Extravascular lung water per gram of dry bloodless lung was greater in lambs (4.82+/-0.11 g) than in sheep (4.45+/-0.08 g), but there was no histologic evidence of pulmonary edema in either group of animals. These findings suggest that lambs have more transvascular filtration of fluid per unit lung mass than sheep, but that microvascular sites for protein exchange do not differ appreciably in lambs and sheep. To test this conclusion, we measured steady-state lymph flow in three lambs before and after raising pulmonary microvascular pressure by rapid intravenous infusion of saline. Lymph flow increased as a function of the net transvascular driving pressure (hydraulic pressure gradient-protein osmotic pressure gradient). This response was almost identical to that of four sheep with pulmonary microvascular pressure augmented by inflation of a balloon in the left atrium. In eight lambs we measured the time for intravenously injected (125)I-albumin to equilibrate in lymph at half the specific activity of plasma: the protein tag equilibrated faster than in sheep. This difference could be explained partly by the higher pulmonary arterial and left atrial pressures of lambs than sheep, and possibly by the presence of more microvascular sites for protein exchange relative to the volume of distribution of protein in the lung of the younger animals.


Amelioration of endothelial abnormalities by prednisone in experimental thrombocytopenia in the rabbit. Experimental thrombocytopenia results in endothelial alterations associated with bleeding. In this study prednisone was shown to prevent or reverse these changes, which supports the clinical inference that adrenocorticosteroids decrease capillary fragility in thrombocytopenia. Rabbits (3-4 kg), intraperitoneally injected with busulfan, developed 98-99% reductions in platelet count and hemorrhaged profusely. Orally administered prednisone (0.2 mg/kg or 1.0 mg/kg daily) reduced bleeding despite persistent thrombocytopenia. Tongue biopsies obtained after 3 days of prednisone treatment were examined by electron microscopy. Normal rabbits served as controls. 25 consecutive capillaries or venules from each of four animals in the control group and each of five experimental groups were examined for fenestrations, "thin spots" (<800 A thick), and mean wall thickness as determined by planimetry. Vessels from control animals had no thin spots or fenestrations, and the mean vessel wall thickness was 4,254+/-105 A SEM. The 100 vessels from the thrombocytopenic animals had a mean vessel wall thickness of 2,081+/-218 A (P < 0.001), and 42 had thin spots of fenestrations. After administration of the smaller dosage of prednisone, the mean vessel wall thickness increased to 3,556+/-40 A (P < 0.001), and only nine vessels had thin spots or fenestrations. With the larger dosage, only six vessels had thin spots or fenestrations and the mean vessel wall thickness of this group increased to 3,704+/-206 A (P < 0.005). All preparations demonstrated normal endothelial junctions. The data are consistent with the hypothesis that the bleeding of thrombocytopenia is caused by altered capillary and venule endothelium and that diminished bleeding observed with prednisone administration results from amelioration of these endothelial changes.


Plasma calcitonin in normal man. Differences between men and women. We measured plasma calcitonin concentrations in healthy volunteers (20 men, ages 23-45 yr, mean, 30 yr; 25 women, ages 21-46 yr, mean, 30 yr) with a radioimmunoassay capable of detecting 5 pg of calcitonin/500 mul incubation volume, or 25 pg/ml of unextracted plasma. All subjects had 4-h calcium infusion (15 mg Ca/kg), and 24 subjects had intravenous pentagastrin injection (0.5 mug/kg) on separate days. Men had higher basal plasma immunoreactive calcitonin concentrations than women (P < 0.001): mean, 49 pg/ml (range, <25-73) and 31 pg/ml (range, <25-51), respectively. 18 of the 20 men (90%) responded to induced hypercalcemia with increases in plasma immunoreactive calcitonin; only 14 of the 25 women (56%) responded. In men, the mean increase of plasma immunoreactive calcitonin+/-SE was 58+/-9 pg/ml, but for women was only 25+/-6 pg/ml. 8 of 10 men (80%) responded to pentagastrin with an increase of plasma immunoreactive calcitonin >30 pg/ml, compared with such a response in only 1 of 14 women (7%). These differences of plasma immunoreactive calcitonin responses between the sexes were statistically significant (calcium infusion, P < 0.02; pentagastrin, P < 0.001). The physiologic importance of these observations is unknown, but we speculate that a lifelong, relative deficiency of calcitonin in some women could play a role in age- and sex-related bone loss, particularly during the estrogen-deficient postmenopausal years.


Catecholamine uptake, accumulation, and release in acute porphyria. Hypertension and tachycardia are well known features of acute porphyria and have been shown to be related to increased circulating catecholamines. The mechanism by which circulating catecholamines are increased was studied using the isolated perfused rat heart and human platelets as a model of adrenergic neuronal function. It was found that neither delta-aminolevulinate (ALA) nor porphobilinogen (PBG) blocked uptake or caused release in the isolated perfused rat heart. Platelets from six patients with acute prophyria, three in remission and three latent, with matching normal controls were studied with regard to their uptake of [(3)H]norepinephrine in the presence of ALA or PBG. It was found that ALA and PBG significantly reduced uptake and accumulation of [(3)H]-norepinephrine in patients with acute porphyria; however, no similar reduction in uptake and accumulation was observed in the platelets of normal controls. Therefore, it appears that there is a latent defect in the catecholamine uptake and (or) accumulation of platelets of patients with acute prophyria which only manifests itself in the presence of ALA or PBG. If platelet uptake serves as a model of adrenergic neuron uptake, this suggests that elevated circulating catecholamine levels during acute attacks of acute porphyria are caused at least partially by blockade of re-uptake into the sympathetic neurons.


Human lymphocyte complement receptors. Quantitative requirements for C3 of normal and chronic lymphocyte leukemia lymphocytes. Erythrocytes coated with varying amounts of human complement were used to detect lymphocytes with complement receptors from normal subjects and patients with chronic lymphocytic leukemia. The relationship between the percentage of lymphocytes rosetting and the quantity of C3 present on complement-coated erythrocytes were studied. Small quantities of C3 (less than 5 fg/erythrocyte) caused maximal rosetting of normal lymphocytes. Maximal rosetting with chronic lymphocytic leukemia lymphocytes was not reached until much greater amounts of C3 were used to coat the erythrocytes. This difference in sensitivity to erythrocyte-bound complement was not due to an increased fraction of complement receptor-bearing cells in the leukemic patients. This loss of sensitivity of the chronic lymphocytic leukemia lymphocyte for complement may play a role in the immune deficiency present in this disease.


Kinetic analysis of 25-hydroxyvitamin D3 metabolism in strontium-induced rickets in the chick. Kinetic data analysis was used to derive a six-compartment computer model which describes the in vivo [3H]25-hydroxyvitamin D3 ([3H]25-OHD3) metabolism in control and strontium rachitic chicks. Plasma concentrations of 25-OHD3 (13 pmol/ml) and 25, 25-dihydroxyvitamin D3 (0.9 pmol/ml) were 18 and 125% greater than controls, respectively, whereas the corresponding level for 1alpha,25-dihydroxyvitamin D3 (0.3 pmol/ml) was only 30% of control. Plasma disappearance of 25-HOD3 was fitted using a two-compartment model in which the metabolite extrapolated half-life was nearly twice as large for strontium rachitic chicks (71 compared to 41 h). Intestinal sequestration of 1alpha,25-dihydroxyvitamin D3 was assumed to be irreversible and was fitted by a single exponential term in which metabolite uptake rate and tissue concentration in strontium rickets was suppressed to 20 and 10% of control, respectively. In contrast, uptake of 25-OHD3 by the intestine was observed to occur by a reversible process in which metabolite concentration was 45% greater in the strontium rachitic compared to control group. The developed compartment model accepts time-dependent control or perturbed metabolite data for the plasma and (or) intestinal pools and provides quantitative values for metabolite pool size, flux rate, and turnover time.


Hypoxic ventilatory response in subjects with normal and high oxygen affinity hemoglobins. It has still not been shown unequivocally whether a decrement of arterial oxygen content or tension governs the ventilatory response to hypoxia. In an attempt to discriminate between the two possibilities, we have measured the ventilatory response to isocapnic progressive hypoxia in two healthy children with a high oxygen affinity hemoglobin (Hb Andrew-Minneapolis) and in their age- and sex-matched normal siblings. Hypoxic ventilatory response was identical in all subjects, there being no difference in minute ventilation at PAo2 = 40 mm Hg or in k (decrement of PO2 required to increase ventilation by a factor of 2.718). In contrast, at PAo2 = 40 mm Hg, hemoglobin oxygen saturation decreased markedly in controls but only slightly in high affinity subjects. Furthermore the increase in heart rate at PAo2 = 40 mm Hg was significantly less in high affinity subjects, suggesting a concomitant difference in oxygen delivery. Thus, with identical decrements in PAo2 but widely divergent changes in arterial oxygen content and oxygen delivery, controls and high affinity subjects showed virtually identical ventilatory response to hypoxia. We conclude that decrements of oxygen tension are the major stimulus for hypoxic ventilatory response.


The effects of gastrin, gastric inhibitory polypeptide, secretin, and the octapeptide of cholecystokinin upon immunoreactive somatostatin release by the perfused canine pancreas. The effects of gastrin, gastric inhibitory polypeptide, secretin, and the octapeptide of pancreozymin-cholecystokinin on immunoreactive somatostatin release were studied in the isolated perfused dog pancreas. Gastrin at a concentration of 65 ng/ml and the octapeptide of pancreozymin-cholecystokinin at a concentration of 25 ng/ml produced a prompt, but transient statistically significant, twofold rise in mean somatostatin concentration. Secretion at a concentration of 0.3 U/ml and gastric inhibitory polypeptide concentration of 58 ng/ml produced a prompt two- to threefold rise in mean somatostatin release, which persisted throughout the perfusion period. With all four polypeptides the pattern of the somatostatin response resembled that of insulin. It appears that pancreatic somatostatin release is stimulated by gastrointestinal hormones that influence the secretion of insulin and glucagon.


The role of phosphate in the action of vitamin D on the intestine. The response of chick intestine to vitamin D and its metabolites was studied in an organ culture preparation of chick ileum explants. Both 25-hydroxycholecalciferol (25-OHD(3)) at a concentration of 20 ng/ml or greater and 1,25-dihydroxycholecalciferol [1,25-(OH)(2)D(3)] at a concentration of 50 pg/ml or greater stimulated the rate of accumulation of [(32)P]phosphate and (45)Ca by the explants and the incorporation of [(3)H]thymidine into DNA. The accumulation of [(32)P]phosphate by the explants was against a concentration gradient and inhibited by ouabain and dinitrophenol. Two saturable mechanisms appeared to mediate the cellular accumulation of phosphate with K(a) of 0.0047 and 0.125 mM, respectively. The V(max) of the lower affinity transport mechanism was accelerated by 1,25-(OH)(2)D(3). Actinomycin D (5.0 mug/ml) did not block the intestinal response to 1,25-(OH)(2)D(3) stimulation of both [(32)p]phosphate and (45)Ca accumulation. Significant stimulation of [(32)P]phosphate accumulation was observed 30 min after the addition of 1,25-(OH)(2)D(3), preceding the sterol-induced increase in the rate of (45)Ca uptake by 30 min and the sterol-induced increase in [(3)H]thymidine incorporation into DNA by 150 min. Increasing extracellular phosphate concentration to 3.0 mM increased [(3)H]thymidine incorporation into DNA and the rate of (45)Ca uptake by the explants. Reducing extracellular phosphate concentration to 0.05 mM attenuated the response of the explants to 1,25-(OH)(2)D(3). From these observations it is postulated that the primary action of vitamin D sterols in the intestine is to enhance the ability of the mucosal cell to accumulate phosphate. The data suggest that restoration of intracellular phosphate levels may then permit expression of the cells' response to vitamin D sterols.


The histocompatibility system in juvenile, insulin-dependent diabetic multiplex kindreds. We have histocompatibility (HLA) genotyped 24 families with two or more juvenile, insulin-dependent, ketosis-prone diabetic siblings. This criterion for family selection was used to obtain a homogeneous form of diabetes within a sibship, because diabetes appears to be a genetically heterogeneous disease. 58 diabetic and 53 nondiabetic sibs and 40 parents were studied. 55% of the diabetic pairs were concordant for both HLA haplotypes (expected 25%), 40% were concordant for one haplotype (expected 50%), and 5% were discordant for both haplotypes (expected 25%). These values are significantly different from the expected values (P < 0.001). On the other hand, the inheritance of haplotypes among the nondiabetic sibs in these families was not significantly different from the expected mendelian segregation. When comparing 20 pairs of HLA identical (sharing two haplotypes) with 15 pairs of haploidential (sharing one haplotype) diabetic sibs for the intrapair difference in age of onset of disease, we found that the HLA identical sibs were significantly more concordant for age of onset (3.9 yr difference) than the haploidential (7.3 yr difference) (P < 0.05). The same type of analysis for the difference in seasonal incidence in months revealed that the HLA indentical sibs were more concordant (1.8 mo difference) than the haploidentical sibs (3.2 mo difference) (P < 0.025). Furthermore, the HLA identical diabetic sibs were more likely to develop diabetes in the winter months (78%) than the haploidentical diabetic sibs (21%). No particular HLA haplotype or antigen seemed to be associated with any particular clinical feature. These data are compatible with the theory of genetic heterogeneity of juvenile, insulin-dependent diabetes. It is suggested that there are one or more diabetes response genes in the HLA region playing an important role in the pathogenesis of juvenile, insulin-dependent diabetes in the families studied here. It is, however, possible that other genes, not associated with the HLA complex, may play an etiologic role in some cases of juvenile, insulin-dependent diabetes, resulting in lack of association between HLA and some forms of diabetes.


Release of platelet constituents by monosodium urate crystals. The release of human platelet constituents by the etiologic agent of gout, the monosodium urate crystal, is described here. In suspensions of washed platelets, response to urate crystals proceeded in two phases: A secretory phase involved the rapid active release of serotonin, ATP, and ADP with little loss of lactic dehydrogenase or beta-glucuronidase. A lytic phase involved the slower loss of all platelet constituents. Both phases were inhibited by iodoacetate plus dinitrophenol, suggesting an energy requirement. In ultrastructural studies, lysis of washed platelets which appeared to contain crystals was seen. Urate crystals were also shown to induce serotonin release and platelet lysis in citrated platelet-rich plasma. Since urate crystals are deposited at a variety of sites, urate crystal-platelet interaction in vivo is a possibility. Such interactions, leading to release of platelet constituents, might contribute to gouty inflammation or to enhanced atherogenesis.


Estimation of the prevalence of udder infection in dairy herds based on a single-quarter sample from each cow in the dairy herd. Individual quarter milk samples were taken from 719 cows in 7 dairy herds and examined for mastitis-causing pathogens. Analyses were made to ascertain the prevalence of mastitis infection when the results from a single quarter were compared with those from all 4 quarters. There was a very close similarity between the 2 methods of assessment. When the number of samples is limited, sampling of a single quarter instead of all 4 quarters permits more cows to be examined.


Vibrotactile frequency for encoding a speech parameter. Frequency of vibration has not been widely used as a parameter for encoding speech-derived information on the skin. Where it has been used, the frequencies employed have not necessarily been compatible with the capabilities of the tactile channel, and no determination was made of the information transmitted by the frequency variable, as differentiated from other parameters used simultaneously, such as duration, amplitude, and location. However, several investigators have shown that difference limens for vibration frequency may be small enough to make stimulus frequency useful in encoding a speech-derived parameter such as the fundamental frequency of voiced speech. In the studies reported here, measurements have been made of the frequency discrimination ability of the volar forearm, using both sinusoidal and pulse waveforms. Stimulus configurations included the constant-frequency vibrations used by other laboratories as well as frequency-modulated (warbled) stimulus patterns. The frequency of a warbled stimulus was designed to have temporal variations analogous to those found in speech. The results suggest that it may be profitable to display the fundamental frequency of voiced speech on the skin as vibratory frequency, thought it might be desirable to recode fundamental frequency into a frequency range more closely matched to the skin's capability.


Analog of two-tone suppression in whole nerve responses. Some similarities are shown between single-unit two-tone suppression areas and those derived from the difference of compound action potential tuning curves obtained with simultaneous and forward masking.


Ultrasonic attenuation of myocardial tissue: dependence on time after excision and on temperature. The ultrasonic attenuation coefficient of myocardium over the frequency range 2-10 MHz has been measured in vitro as a function excision and as a function of temperature. Results indicate that the attenuation coefficient was approximately independent of time for 4 h following excision at 19.5 degrees C, but increased by about 20% over a 4-h interval at 35 degrees C. The attenuation coefficient decreases approximately linearly with increasing temperature over the range 20.5 degrees -37 degrees C, with the value at 37 degrees C being about 20% lower than at 20.5 degrees C.


Two-tone auditory spectral resolution.

Two-tone auditory spectral resolution. Two component complex tones were synthesized so that each member of a complementary pair exhibited identical amplitude modulations; frequency modulations, however, were in opposite directions. Previous work has shown that the discriminability of the members of a complementary pair is related to the envelope-weighted differences in their instantaneous frequency functions. Listeners report that they base their discriminations upon differences in pitch between complementary two component signals. We assumed that the high discriminability found for moderate separations between the two component frequencies would not obtain if the components were resolved into separate critical bands. Thus we could define the just discriminable (75%) frequency separation as a direct estimate of spectral resolving power without recourse to assumptions about masking effectiveness, loudness summation, or other subjective changes thought to depend upon auditory spectral resolving power. Our findings indicate that resolution bandwidths resulting from the discriminability of complex tone pairs approximate the width of the traveling-wave envelope observed by von Békèsy. In light of our results, the implications for other critical bandwidth estimates are discussed.


Detection and recognition of pure tones in noise. We examine the predictions of a new theorem relating signal identification (specifying a signal as a particular member of a set of potential signals) to signal detection (discriminating the presence of a signal). The theorem, derived in the context of signal-detection theory, requires that the signals be equally detectable and orthogonal. Our sinusoidal signals are partially masked by noise and their intensities adjusted to produce equal-signal detectability; we do not examine this assumption of the theorem. The theorem generally provides a reasonably accurate description of recognition performance for two-signal and four-signal conditions and is equally accurate for both the Yes-No and category-rating procedures. In a preliminary investigation of the orthogonality assumption, we varied the frequency separation between two signals. When the frequency separation between two signals is small (20 Hz near 1 kHz), the theorem fails to provide a good description of performance.


Noncategorical perception of stop consonants differing in VOT. The discriminability of bilabial stop consonants differing in VOT (the Abramson-Lisker bilabial series) was measured in a same-different task, an oddity task, and a dual response, discrimination--identification task. Subjects showed excellent within-category discrimination in all three tasks after a moderate amount of training in a same-different task with a fixed standard and with feedback. In addition, discrimination performance continuously improved with increasing stimulus difference for both intra- and intercategory comparisons. Also, subjects were able to alter their identification responses so that well-defined category boundaries fell at arbitrary values determined by the experiments. These results are not compatible with a strict interpretation of the categorical perception of stop consonants.


Effect of final-syllable position on vowel duration in infant babbling. Previous research has suggested possible speech-production- and/or speech-perception-oriented causes for the temporal phenomenon referred to as final-syllable vowel lengthening, yet little conclusive evidence has been adduced for either possibility. The present study represents an attempt to provide additional information concerning the nature of this phenomenon by approaching the issue from a developmental perspective. A much smaller amount of final-syllable vowel lengthening was observed in the premeaningful vocalizations of a number of very young infants than in phonetically comparable utterances produced by adult speakers of English. It is concluded on the basis of this preliminary evidence that extensive final-syllable lengthening observed in the productions of adult speakers of English seemingly constitutes a learned behavior.


Control of vocal-tract length in speech. Essential for the correct production of vowels is the accurate control of vocal-tract length. Perkell [Psychology of Speech Production (MIT, Cambridge, MA, 1969)] has suggested that two important determinants of vocal-tract length are vertical larynx position and lip spreading/protrusion, often acting together. The present study was designed to determine whether constraining lip spreading/protrusion induces compensatory vertical larynx displacements, particularly on rounded vowels. Upper lip and larynx movement were monitored photoelectrically while French and Mandarin native speakers produced the vowels /i,y,u/ first under normal-speech conditions and then with lip activity constrained. Significant differences were found in upper-lip protrusion and larynx position depending on the vowel uttered. Moreover, the generally low-larynx position of rounded vowels became even lower  when lip protrusion was constrained. These results imply that compensatory articulations contribute to a contrast-preserving strategy in speech production.


Frequency of W4 and W6 antigens in perennial, nonallergic asthmatics. The frequency of W4 and W6 antigens was determined in 39 perennial, nonallergic asthmatics and 53 normal controls. The data indicated that the frequency of asthmatics homozygous for W4 or W6 was not different from the unrelated control population. Hence, our data dispute the hypothesis that intrinsic asthma is an autosomal-recessive disease associated with the W6 antigen.


Oropharyngeal candidiasis in patients treated with triamcinolone acetonide aerosol. Thirty asthmatic patients participating in a trial of triamcinolone acetonide aerosol were evaluated to determine the relationships among symptons of sore throat or hoarseness, the appearance of the throat on physical examination, and the presence of yeasts on pharyngeal culture. Observations were recorded prior to aerosol therapy and repeated after 2 wk, 4 wk, 6 wk, 4 mo, and 6 mo of therapy. A total of 15 patients (50%) experienced sore throat or hoarseness, 15 (50%) had yeasts cultured from the pharynx on at least one occasion, and 11 (37%) at some point had an abnormal throat examination; however, there was no predictable relationship between symptoms or abnormal physical examinations and the presence of a positive culture. The frequency of positive cultures did not change significantly during the observation period. Twelve patients had positive yeast cultures on 50% or more of their samples. The incidence of symptoms was not sigficantly increased in these chronically colonized patients. Symptoms were usually transient, and discontinuation of the aerosol or antifungal therapy was unnecessary. Triamcinolone aerosol was not associated with significantly increased pharyngeal colonization with yeasts in this 6-mo study. Existing chronic colonization is not necessarily a contraindication to triamcinolone therapy. Sore throat and hoarseness are usually unrelated to yeast infection in patients using triamcinolone acetonide aerosol.


Agnogenic venous mesenteric thrombosis.

Agnogenic venous mesenteric thrombosis. One of the most difficult diagnoses to establish is that of agnogenic venous mesenteric thrombosis (AVMT). This disorder occurs chiefly in elderly patients and, unless diagnosed promptly, leads to death in most instances. AVMT may follow surgical operations or occur during a prolonged illness. In the past five years at St. Clare's Hospital and Health Center in New York City, this diagnosis was established in five patients. In reviewing these cases, it was noted that some of the signs and symptoms such as those due to hypotension and shock with marked leukocytosis, were out of proportion to those usually observed when the preoperative diagnosis is being considered. The pathologic and radiologic characteristics of this disorder are outlined, and the recommended operative procedure for treatment is discussed. The importance is stressed of prompt, vigorous and prolonged anticoagulation therapy in order to minimize the chance of recurrence in the early postoperative period. Anticoagulant therapy is also effective preoperatively, if the disease is diagnosed sufficiently early. As greater numbers of elderly patients are being treated in hospitals, this dire complication should be uppermost in the minds of physicians and surgeons if a fatal outcome is to be avoided following a successful operative procedure.


Geriatrics program for medical students and family practice residents. I. Establishing attitudes toward the aged. This report concerns the initiation of required experience in geriatrics for undergraduate medical students and a program of research designed to evaluate that experience. Through the use of questionnaires, an attempt was made to differentiate between attitudes toward the elderly and their rehabilitation potential as stated by medical students, family practice residents, and professional and nonprofessional nursing-home staff members. Important differences were found between professional and nonprofessional groups, but no significant differences among professionals. Implications for the training of professional and nonprofessional staff members are discussed, and further research plans specified.


Evaluating the quality of nursing home care. Evaluation of the quality of care that a nursing home patient receives is difficult and requires physician participation as well as the participation of specially trained nursing personnel. A form of limited medical audit is suggested to aid in such evaluation. In the proprietary nursing home studied by the authors, the quality of care was not being effectively assessed by the survey process then employed. In addition to other factors, emphasis is now placed on the avoidance of additional costs or extra paper work in the process of determining the quality of care.


The diagnosis of amblyopia and strabismus: a programmed approach. A simplified method of recording and analyzing amblyopic and strabismic examinations is presented. With this new form, the average practitioner is provided with a relatively standardized set of tests in a logical, organized sequence. Programming the patient's responses into meaningful categories facilitates the formation of a differential diagnosis and also provides valuable insight into the eventual outcome of each case.


Intermittent exotropia of the divergence excess type. Sensory and motor anomalies of the intermittent exotropia, the divergence excess type, have been described by various authors. However, previous theories of etiology fail to incorporate all the sensory motor anomalies typically found. The present paper attempts to develop a theory of etiology based upon sensory-motor findings and to offer a treatment plan consistent with those findings.


Migraine: fusional-eye movement stress.

Migraine: fusional-eye movement stress. This paper indicates that the sources of migraine have always been in doubt, from ancient times when physicians first described the syndrome of migraine without clarifying it sources to the present day when physicians, still in some doubt, contend that excess of such substances as acetylcholine or serotonin may trigger the migraine. This paper argues that dynamic binocular seeing, normally a stress function, excites the migraine headache, primarily, howver, among visual pain sensitive individuals. Cases are offered whose migraine is relieved by creating a finer binocular seeing balance through fusion-eye movement training with the V.T. Reading Aid.


The role of fatty acid oxidation in the epidermis. Using cultured epidermal cells from guinea pig ears, we have determined that the epidermis has a consistenly low respiratory quotient which is indicative of lipid metabolism. When the tissue was supplied with an exogenous source of free fatty acid, the rate of oxidation was quite large. Inhibition of fatty acid oxidation by alpha-bromopalmitate, an inhibitor of fatty acid oxidation in other mammalian cells, was associated with a decrease in both the rate of respiration and a decrease in the total pool of adenosine triphosphate (ATP). These data indicate that alpha-bromopalmitate, through its inhibtory effect on fatty acid oxidation, decreases the amount of substrate entering the tricarboxylic acid cycle which in turn decreases the rate of both oxygen uptake and ATP production. A consequence of this lowered ATP level is a decreased rat of DNA synthesis, an effect which may be beneficial in controlling hyperproliferative diseases of the skin.


Dermal toxicity of 8-methoxypsoralen administered (by gavage) to hairless mice irradiated with long-wave ultraviolet light. Hairless mice were administered various amounts of 8-methoxypsoralen (8-MOP) by gavage, followed by irradiation with ultraviolet light (UVA) two or more times per week for periods ranging from 1 to 12 months. The minimum phototoxic dose was 20 mg/kg body weight by this route of administration and potential for serious organ toxicity in long-term exposures was investigated. No histologic features of cutaneous malignancy were encountered under test conditions which produced prolonged phototoxicity, deep ulceration, cicatrization, and other deformities. Repeated daily gavaged doses of 20 mg psoralen/kg body weight in conjunction with twice weekly irradiation for 10 min with UVA elicited an erythematous phototoxic reaction, but did not give rise to subsequent skin lesions. 8-MOP in repeated daily gavage doses of 30 mg and 40 mg/kg body weight combined with twice weekly UVA irradiation for 10 min caused severe burning with subsequent scarring, but did not induce malignant tumors in experiments lasting lasting 8 months. No organ toxicity was seen except for toxic liver changes when severe cutaneous burn and pronounced ulcerations were produced. Limited immunologic studies disclosed no abnormalities in this system.


Corticosteroid-induced dermal atrophy in the rat. Corticosteroid-induced dermal atrophy has been studied in the rat using daily application of ethanolic solutions to small areas of flank skin. After 12 days of treatment, the degree of atrophy was determined by comparing the weights of skin plugs (16 mm diameter) taken from the treated areas with contralaterally paired control areas. Doses can be adjusted so that systemic effects are minimized and only local effects are observed. Hydrocortisone, hydrocortisone butyrate, dexamethasone, betamethasone, desonide and triamcinolone acetonide all produce atrophy in the rat, and the degree of thinning is dose dependent. Potencies in the dermal atrophy assay compare directly with topical anti-inflammatory potencies in the rat, and the presence of fluorine in the steroid molecule is not a determining factor in the production of atrophy.


Effects of retinoic acid on embryonic chick skin. The influence of vitamin A on differentiating epithelia was examined in explants of skin from 14-day chick embryos exposed to retinoic acid (RA) in low, moderate, and high doses. The changes observed in RA-treated cultures are both dose- and time-dependent and are reversible when explants are transferred to control medium. The periderm sloughs prematurely and horizontal stratification is lost. Keratinization is inhibited and fewer desmosomes and tonofilaments are seen. Surface epidermal cells develop microvilli, bulge upwards, and detach. Golgi elements, rough endoplasmic reticulum, and polyribosomes are unusually prominent. Mucin granules form and gland-like structures develop with intercellular canaliculi characterized by tight junctions, brush borders, and dense secretory contents. On the basis of present evidence there are several possible mechanisms by which RA could alter epidermal differentiation. RA-induced gaps in the basal lamina allow direct contact between epidermal basal cells and fibroblasts and collagen fibers which could result in inappropriate dermal signals reaching the epidermis. In younger embryos the entire epidermis, including the mitotically inactive surface cells, appears to respond to RA, and this could imply an epigenetic modulation of cell phenotype. Finally, after the formation of a stratum corneum in older embryos only the relatively undifferentiated basal layer shows a metaplastic response, indicating that RA could be acting directly on the genome.


Leukocytoclastic vasculitis: sequential appearance of immunoreactants and cellular changes in serial biopsies. To study the mechanisms responsible for leukocytoclastic vasculitis, we evaluated the kinetics of immunologic and cellular changes in induced vasculitis lesions. In four of five consecutive patients with active vasculitis, lesions were induced by increasing vascular permeability via injecting histamine into the skin. Biopsies were obtained for light and electron microscopy and immunofluorescence at 1, 4, 8, and 24 hr after injection. The results show that immunoglobulin, C3, and electron-dense material are deposited in vessel walls early and are followed by cellular infiltration. The characteristics of the cellular infiltrates were quite diverse at different times after histamine provocation and no distinctive patterns were seen. Nevertheless, the kinetics of the appearance of immunoreactants and cells implies that immunoglobulin and probably circulating immune complexes are present prior to the development of inflammation and supports the contention that deposition of immune complexes within vessel walls is responsible for leukocytoclastic vasculitis.


Epidemiologic and clinical features of an outbreak of bubonic plague in New Mexico. An outbreak of seven cases of bubonic plague in New Mexico was investigated. Clinical features were studied and correlated with field studies in an attmept to determine the source of infection in patients with indefinite histories of exposure. Most patients presented with fever, malaise, and an acute painful lymphadenitis (bubo). One death occurred in a patient with bubonic-septicemic plague complicated by meningitis due to Yersinia pestis. All patients lived in rural or semirural areas, and most had been in the general vicinity of their usual residence during the six days prior to onset of symptoms. The outbreak was associated with probable epizootics in rodents in two different areas of the state. One case was traced to direct hand contact with plague-infected rabbits. One patient developed insect bites after sleeping in the same bed with a flea-infested cat. Three of the other five patients had insect bites, presumably flea bites, but none of the five recalled contact with rodents or rabbits. Four of the five, however, had been in contact with dogs or cats that were later shown to have titers of antibody to Y. pestis. These findings provide further support for the hypothesis that contact with domestic dogs and cats may result in direct or indirect transmission of Y. pestis to humans.


Impaired response of lymphocytes of diabetic subjects to antigen of Staphylococcus aureus. The lymphocyte response to antigen of Staphylococcus aureus was examined in 67 uninfected diabetic subjects and in 71 age-matched subjects who were not diabetic. Peripheral blood lymphocytes were exposed to phytohemagglutinin and to antigen of S. aureus in triplicate cultures in the lymphocyte transformation assay. Diabetic subjects including those who were in good metabolic control had significantly decreased responses to staphylococcal antigen (P less than 0.05) but not to phytohemagglutinin. The use of fetal calf serum in place of autologous plasma in the nutrient medium did not correct the defect. Lymphocytes from normal subjects were cultured in diabetic plasma as well as in autologous plasma; the differences were not significant. These findings indicate that diabetic persons have an impaired response to staphylococcal antigen, a defect which appears to be in the lymphocyte itself and not in the serum factor.


Correlation of metabolic and chemiluminescent responses of granulocytes from three female siblings with chronic granulomatous disease. Polymorphonuclear leukocytes (PMNL) from children with atypical chronic granulomatous disease (CGD), their mother and siblings, and normal controls were studied in regard to glycolytic and hexose monophosphate shunt activities in the resting, methylene blue-stimulated, and phagocytizing states. PMNL from the patients with CGD had normal glycolytic and hexose monophophate shunt activities in the resting state and after stimulation with methylene blue. However, stimulation of the hexose monophosphate shunt after phagocytosis was greatly decreased. These data were correlated with studies of both initial rate and integral counts of chemiluminescence. The chemiluminescent response from patients with atypical CGD was also greatly decreased. This decreased response probably reflects a defect in the oxidative destruction of the phagocytized microbe and correlates well with the decreased activity of the phagocytically activated hexose monophosphate  shunt. The defect in generation of radical species of oxygen, singlet oxygen, and chemiluminescence by leukocytes from patients with CGD is discussed.


Yaws in the Americas, 1950-1975.

Yaws in the Americas, 1950-1975. Yaws was introduced into the Americas by African slaves beginning in the 16th century and may have already been present before the arrival of Columbus. In the 1950s, programs for the eradication of yaws were undertaken in almost all American countries in which yaws was endemic. By mass treatment of cases and contacts with penicillin, the programs against yaws have dramatically reduced the incidence of reported cases throughout the Western Hemisphere from greater than 44,000 cases per year during 1950-1954 to 437 cases in 1975. In Brazil, efforts against yaws reduced the number of patients treated by 99% between 1965 and 1974. By 1975, yaws apparently remained a significant public health problem in only a few communities in Brazil, Columbia, Dominica, Ecuador, Haiti, Peru, St. Lucia, and St. Vincent, and possibly in Guiana and Surinam. It may be possible to eliminate infectious yaws entirely from the Western Hemisphere within the next few years.


Kinetics of immunological responses, resistance to reinfection, and pathological reactions to infection with Trichinella spiralis. Changes in immune responses, resistance to reinfection, and pathological reactions were studied serially in mice that had been infected for four to 40 weeks with 150 larvae of Trichinella spiralis. Immediate footpad hypersensitivity reactions to antigens of Trichinella were present throughout the period of observation. Delayed hypersensitivity reactions 48 hr after injection of antigen were first seen in mice infected for 14 weeks and gradually increased in size thereafter. Intestinal adult worm burdens were determined one week after challenge with 5000 larvae. There was resistance to reinfection and accelerated expulsion of worms in animals challenged three weeks after the primary infection; this resistance waned at seven and 13 weeks but reappeared in mice infected for 20 weeks or longer. Counts of larvae in muscle were determined four weeks after challenge with 5000 larvae. Marked resistance was present four weeks after the primary infection and was maintained for the duration of the study.


Hepatitis B e antigen and infectivity of hepatitis B virus. For confirmation of the difference in the infectivity of hepatitis B surface antigen (HBS Ag)-positive serum according to differences in the e antigen system, four chimpanzees were inoculated with serum positive for hepatitis B e antigen (HBe Ag), and three chimpanzees were inoculated with serum positive for antibody to HBe Ag (anti-HBe). Since the infectivity titrations are not yet completed, the end infectivity titer of each serum is not known. All four chimpanzees given injections of 10(-1), 10(-4), or 10(-8) dilutions of HBe Ag-positive serum developed hepatitis B virus infection, whereas the one chimpanzee injected with undiluted anti-HBe-positive serum became infected, and other chimpanzees injected with diluted anti-HBe-positive sera did not. As judged from the length of the incubation period before appearance of HBS Ag in blood, there seemed to be a remarkable difference in infectivity between the HBe Ag-positive serum and the anti-HBe-positive serum; the former serum was 10(8) times more infectious than the latter.


In vitro adherence of Kanagawa-positive Vibrio parahaemolyticus to epithelial cells. Kanagawa-positive Vibrio parahaemolyticus adhered rapidly to suspension-grown HeLa cells and to human fetal intestinal (HFI) cells in monolayer. Kanagawa-negative V. parahaemolyticus did not adhere to HeLa cells and adhered to HFI cells at a much slower rate than Kanagawa-positive bacteria. In the HFI cell system, adherence was dependent on the presence of calcium in the incubation mixture. It was unaffected by pretreatment of the HFI cell monolayer with neuraminidase or potassium periodate. Adherence was unaffected by neuraminidase or ultraviolet irradiation of bacteria but was decreased by heat, ethanol, or periodate pretreatment. These results suggest that adherence of Kanagawa-positive V. parahaemolyticus to epithelial cells in vitro depends on interaction between the cell surface of the bacteria and the epithelial cell and that a carbohydrate on the outer membrane of the bacterial cell wall is necessary for this interaction.


Enzyme-linked immunosorbent assay for hepatitis B surface antigen. A solid-phase enzyme-linked immunosorbent assay (ELISA), based on the "sandwich" principle with use of microtiter plates, was developed for the detection of hepatitis B surface antigen (HBSAg). Results could be read within one day by the naked eye or by colorimeter. The detection level was less than or equal to 5-10 ng of HBSAg/ml. The sensitivities of ELISA and radioimmunoassay were about the same in dilution series and in a follow-up study of 19 patients with acute hepatitis B infection. In 11 European medical centers where greater than 50,000 samples were tested, ELISA detected significantly more HBSAg-positive samples than a reversed hemagglutinatiom test. No significant difference in sensitivity between ELISA and radioimmunoassay could be demonstrated. On the average, 2.2% of readings were false-positive reactions. Falsely positive samples were identified by a confirmatory test.


Kinetic studies of phagocytosis of IgG-coated latex particles with a thrombocyte counter. An assay was developed making possible the measurement of the initial rate of phagocytosis of IgG-coated polyvinyl toluene latex particles by human leukocytes. With the use of the volume-discrimating ability of a Trombo-Counter, the small latex particles could be selectively counted, but cells and internalized particles were not counted. The phagocytic uptake was greatley enhanced by an IgG coating of the particles as compared to the uptake of uncoated or albumin-coated particles. An almost complete inhibition of particle uptake was obtained at ice-bath temperature and in the presence of N-ethyl maleimide. Heat-inactivated serum and monomeric IgG inhibited the phagocytic reaction. In the presence of fresh serum a stimulatory effect on the final phagocytic capacity was noticed, but the initial rate of particle uptake varied depending on the preincubation time of particles with serum.


Heymann nephritis of rats: beneficial effect of methysergide. Since vasoactive amines may be involved in the pathogenesis of glomerular lesions in glomerulonephritis, the present study was undertaken to evaluate the effect of MS, a serotonin antagonist, on the course of HN in rats. MS was given in drinking water at a concentration of 6 mg/dl to 18 rats for 13 weeks; daily intake of MS varied between 1.3 and 3.9 mg. This intake prevented the effect of 10 to 100 microgram of serotonin on the vascular permeability of skin vessels. Effect of histamine (10 microgram) assessed similarly was not blocked. MS administration was started a week prior to the immunizations for the induction of HN and continued until the animals were sacrificed at 13 weeks. A control group of 20 immunized rats, also observed for 13 weeks, did not receive MS. MS treatment significantly decreased the incidence of heavy proteinuria (p less than 0.001), the severity of proteinuria at each week throughout the course of the disease (p less than 0.001), the amount of immune complex deposition in the glomeruli, and also delayed the onset of proteinuria (p less than 0.001). In addition, three of 18 MS-treated rats did not show evidence of immune complexes in the glomeruli, whereas each control animal did. It is concluded that MS treatment exerts a beneficial effect on the course of HN of rats and may also prevent it in some rats.


Evidence of aluminum absorption from the gastrointestinal tract and bone deposition by aluminum carbonate ingestion with normal renal function. The question of whether aluminum is toxic in patients ingesting large oral loads, either for phosphate binding in renal dialysis or as an antacid for peptic ulcer, has been raised. The permeability of the gut barrier for aluminum has not been established because of the lack of precise analytical techniques. Urine aluminum was measured in this study before and during oral aluminum carbonate loading in six subjects with normal renal function, one of which had peptic ulcer disease and a 25-year history of high oral aluminum ingestion. The analytical procedure involved destructive neutron activation analysis. Aluminum was present in the urine in all instances before loading and rose in every case from 4-fold to 10-fold. Bone aluminum was measured in six autopsy specimens, three dialysis patients, three nondialysis patients, and in an iliac crest biopsy from the peptic ulcer patient who had osteoporosis. The bone biopsy aluminum level in the ulcer patient was intermediate between those of "normal subjects" and patients on dialysis. These results show that the gut barrier is permeable to heavy aluminum load and suggest that bone aluminum deposition occurs in humans with normal renal function.


Specific determination of quinidine and (3S)-3-hydroxyquinidine in human serum by high-pressure liquid chromatography. A sensitive and selective HPLC assay was developed to measure quinidine and (3S)-3-hydroxyquinidine in the serum of patients receiving quinidine. The method involves analysis of a benzene extract of alkalinized serum by a high-pressure liquid chromatograph containing a reverse phase column and a fluorescence detector. The lower limit of sensitivity of this method for these compounds is 5 ng/ml. The coefficients of variation of the assay for quinidine and (3S)-3-hydroxyquinidine are 2% and 6%, respectively. Samples of serum from 10 cardiac patients were found to contain (3S)-3-hydroxyquinidine and quinidine in ratios ranging from 0.18 to 1.0 (mean, 0.38 +/- 0.28 [S.D.]). Quinidine serum levels in these patients determined by HPLC averaged 80% of those determined on the same samples by the routinely used fluorometric assay. The reason for the discrepancy is that this latter assay, involving a double extraction with quantitation in sulfuric acid by fluorometry, is nonspecific for quinidine. The (3S)-3-hydroxy metabolite, having a fluorescence intensity similar to that of quinidine, is 60% extracted under the fluorometric assay conditions.


An improved method for measuring blood mercaptans. An improved method for measuring MT in the blood is described which uses zinc as a reducing agent and utilizes a more sensitive gas chromatograph. The method measures covalently bound MT that was not previously detected and permits determinations in patients for the first time. The average normal whole blood MT in rat blood was 200 +/- 42 pmol/ml and in human blood 229 +/- 29 pmol/ml. Eleven rats in experimental hepatic coma following acute massive hepatic necrosis had blood levels four to 18 times the average normal, and seven cirrhotic patients with hepatic encephalopathy or coma had blood levels four to five times the average normal.


Application of a simple gas chromatographic technique for measuring breath hydrogen. A simple gas chromatographic technique for analyzing H2 in expired air with a compact, relatively inexpensive gas chromatography specifically adapted for H2 analysis is described. Modifications in the basic chromatograph included increasing the capacity of the sample loop, lengthening the column, and using argon as the carrier gas to increase the sensitivity of the system. Methods for collecting and storing respiratory gas samples and for quantifying the results are described for clinical studies of carbohydrate malabsorption. Small errors in collection and quantitation are introduced by the method, but they are minor in relation to the changes in H2 concentration which are seen with significant malabsorption. This simplification of chromatograph technology could increase the general availability of this convenient, noninvasive and well-tolerated test of intestinal absorption of carbohydrates such as lactose.


The effects of alkylureas and nitrogen mustards on the kinetics of red cell sickling. A continuous flow apparatus was designed for the study of the kinetics of red cell sickling. Cells were mixed with buffered sodium dithionite in one mixing chamber and after transversing variable length pathways were fixed with isotonic formalin in a second mixing chamber. Hb SC-containing red cells sickle at a slower rate than Hb SS red cells, exhibiting a clearly detectable log period. The effect of butylurea on sickling of SS or SC cells is due to the inhibition of the extent of sickling as well as the extension of the time required for sickling. This effect is concentration dependent, which suggests that at least some of the pregelling events in a solution of deoxy Hb S are based on hydrophobic interactions. Nitrogen mustards, on the other hand, inhibit the extent of red cell sickling without modifying the rate of sickling at the concentrations used.


Relationship of levels of circulating immune complexes to histologic patterns of nephritis: a comparative study of membranous glomerulonephropathy and diffuse proliferative glomerulonephritis. Immunofluorescent studies have suggested that immune complex deposition is the pathogenetic mechanism responsible for MGN and diffuse PGN. Despite this common mechanism, both renal disorders show considerable differences in the rate of progression of renal functional deterioration. To examine whether differences in the amounts of circulating immune complexes may in part be responsible for these differences, such complexes were assayed for in the sera of the two patient populations by a 1251-C1q binding assay, which has a lower limit of sensitivity for 75 microgram of aggregated human gamma globulin per milliliter of serum. Circulating complexes were found in sera from 11 of 14 patients with diffuse PGN but were undetectable in sera from 13 patients with MGN. Additional evidence for existing differences in the amounts of circulating immune complexes in the two groups was provided by serum C3 measurements. Serum C3 concentrations were below normal limits in nine of 14 sera from patients with diffuse PGN but were within normal limits for sera from all patients with MGN. Sucrose density gradient ultracentrifugation analysis of C1q reactive complexes showed them to have sedimentation coefficients ranging from 14.6S to 18.2S. The sizes of the complexes are consistent with those analyzed in animal models as being capable of inducing nephritis.


Erythrocyte osmotic fragility: micromethod based on resistive-particle counting. A new procedure has been developed to measure the osmotic fragility of human erythrocytes. It is based on the resistive-particle counter and the finding that lysed erythrocytes have a lower electrical resistance than intact cells after the current in the sensing orifice reaches a critical value. The most suitable test conditions involve a 19 mu orifice, a high current setting, and the simple use of size discriminators to exclude lysed cells from being counted. Since only 1 to 5 microliter of blood are needed per salt concentration, a complete fragility test can be carried out with less than 50 mu of blood. Results with the new procedure were comparable to the classic spectrophotometric one for normal blood, in clinical conditions of increased or decreased erythrocyt osmotic fragility, and for different anticoagulants. It has a specific advantage in that ratio counting makes accurate pipetting of blood unnecessary.


An analysis of changes in blood pH following exhausting activity in the starry flounder, Platichthys stellatus. Exhausting activity results in a marked and immediate drop in blood pH which gradually returns to normal over the following 6h. The acidosis is caused largely by elevated Pco2 levels, which vary inversely with pH. Blood lactate concentration increases slowly, reaching a maximum at 2--4h post-exercise, and contributes significantly to the acidosis only late in the recovery period. The slow time course of lactic acid release into the blood permits temporal separation of the peak metabolic acidosis from the peak respiratory acidosis. Evidence is presented that a metabolic acid other than lactic also makes a modest contribution to the pH depression during the recovery period.


The effects of hypoxia and reoxygenation on force development in myocardia of carp and rainbow trout: protective effects of CO2/HCO3. Isometrically mounted and electrically paced myocardial ventricular strips of carp have a much higher capacity to develop force during severe hypoxia and to redevelop force after it than those of rainbow trout. When the concentrations of CO2 and HCO3-in the solutions surrounding the strips were increased together, such that pH remained constant, the force developed during hypoxia increased. The concentration of CO2 was raised from 0-4%; that of HCO3-from 0-25 mM. The effect was much more pronounced in the carp strips than in the trout strips. With the carp strips, the force recovery upon reoxygenation was unaffected by the variations in CO2 and HCO3-. The trout strips, however, recovered better when CO2 and HCO3-had been raised during either hypoxia or reoxygenation.


The control of the diuresis following a blood meal in females of the yellow fever mosquito Aedes aegypti (L). Control of post-feeding diuresis in females of the mosquito Aëdes aegypti has been studied by means of a weighing technique and simple surgical procedures. The primary controlling factor is (as in the larva) a nervous feedback mechanism and not an increased production of diuretic hormone. As the mosquito ingests blood, sensory information from the distending abdomen reaches the mid gut via the nerve cord, brain and stomatogastric system. This information probably inhibits retroperistaltic movements of the mid gut allowing fluid from the Malpighian tubules (which seems to be produced continually) to be moved back to the rectum for subsequent excretion, instead of being re-cycled to the haemolymph via the mid gut. Such a control does not preclude a role for the diuretic hormone, continual secretion of which may cause the continual production of fluid from the Malpighian tubules.


A scanning electron microscopic comparison of the development of embryonic and regenerating limbs in the axolotl. A comparison between the surface features of embryonic limb development and limb regeneration was made in the axolotl. Scanning electron microscopy revealed an overall similarity between embryonic and regenerating limbs. A notable feature was the lack of a morphologically discrete apical epidermal specialization on the surface of any of the limbs. Histological preparations revealed no thickening of the apical epidermis in embryonic limbs. There is a definite thickening of the apical epidermis in regenerating limbs during the stages of dedifferentiation and the early blastemal phases, but the thickening projects into the underlying tissues rather than altering the smooth surface contours of the blastema. Minor differences in epidermal specializations (ciliated cells scattered over the entire body and very irregularly shaped cells with knob-like projections at the tips of digits in embryos) may be attributable to differences in overall activity of the animals at various stages in their life history.


Heart rate response to light in the embryo of the Japanese quail (Coturnix coturnix). The effects of exposure to light were investigated during and shortly after the period of light stimulation. A particular objective was to evaluated any responses to the type of illumination conditions generally used for observation of avian embryos. Twenty 16-day Japanese quail embryos were illuminated for 15 minutes each during a total recording period of 55 minutes. Heart rate, respiration rate and an approximate measure of activity were recorded. Mean heart rate was found to be higher during stimulation than before and did not return to the prestimulation level during the recording period after stimulation ceased. The lack of an immediate heart rate response to the onset of stimulation separates the effects of light from those of touch, rotation, odours, tastes and maternal calls. The possibility that light may act to stimulate accelerated development is discussed.