Retroperitoneal in-line aortic bypass for treatment of infected infrarenal aortic grafts. Since 1970, we have treated 43 patients with infected aortic grafts. Early in the series, four patients were treated with resection of the fistula or erosion and systemic and topical antibiotics without removal of the graft. All four patients died. Thirty-two patients were treated by conventional therapy; there were 13 deaths (40 percent). More recently, seven patients were managed by the left retroperitoneal placement of a new in-line polytetrafluoroethylene (PTFE) aortic graft through clean tissue planes, followed by the immediate transperitoneal removal of the infected graft without cross-contamination. Patients were maintained postoperatively on antibiotics for a minimum of two weeks. All seven patients survived without septic complications, with a mean follow-up time of 36 months (six months to four years). The surgical technique consists of initial suprarenal control of the aorta, followed by infrarenal division and oversewing of the distal aorta. A PTFE bifurcation graft is placed connecting the proximal aorta and the appropriate femoral vessels, the right limb tunneled through the space of Retzius. After closure of the incisions, through the space of Retzius. After closure of the incisions, the patient is placed in the supine position and the infected graft is removed transperitoneally. We believe that retroperitoneal in-line aortic bypass for treatment of an infected aortic graft offers a favorable alternative to conventional therapy by avoiding the use of an extra-anatomic bypass and associated risk of stump blowout.


Observations on prevention and management of vesicovaginal fistula after total hysterectomy. A retrospective study of genital fistulas of the lower urinary tract revealed 91 percent to be postsurgical. Of these, 91 percent occurred after gynecologic procedures. Total hysterectomy was the most common antecedent procedure (n = 110), and the resulting lesion was the vault fistula. Abdominal total hysterectomy was the most frequent operation to precede a vault fistula (n = 92) and almost 70 percent occurred in the absence of factors identified as placing the patient at risk for injury to the bladder. Such risk factors included prior uterine operation, especially cesarean section, endometriosis, recent cold-knife cervical conization and prior radiation therapy. Twenty-four fistulas occurred despite recognition at the time of hysterectomy of injury to the bladder and its prompt repair. Thirty patients had undergone prior failed attempts at repair elsewhere. Three fistulas closed spontaneously. One hundred and seven were repaired by the Latzko technique. There were nine failures, each of which was successfully repaired by a repeat Latzko operation when vaginal reepithelization was complete. Suggestions to avoid injury to the bladder during abdominal total hysterectomy include use of a two-way indwelling catheter when risk factors are present, use of sharp dissection to isolate the bladder, use of extraperitoneal cystotomy when dissection is difficult, filling the bladder when injury is suspected and repair of an overt bladder injury only after mobilization of the injured area. A Latzko repair of a vault fistula is advised because complications are minimal, the postoperative patient is comfortable and the period of hospitalization is five days or less.


The diagnosis and management of dystocia of the shoulder. Dystocia of the shoulder is an unpredictable obstetric emergency that may result in injury to the mother or fetus. In an effort to reduce such risks, attempts have been made to identify patients having a fetus who may subsequently develop shoulder dystocia. The literature, however, clearly reflects that even the combination of prenatal historic facts, estimated fetal weight and sequence of intrapartum events is ineffective in prospectively identifying infants whose births are complicated by shoulder dystocia. During a ten year period at the University of Mississippi Medical Center, the incidence of macrosomia, shoulder dystocia and subsequent brachial plexus injury was reviewed. The majority of instances (89 percent) of shoulder dystocia occurred in patients weighing less than 8 pounds 13 ounces at birth. In the current retrospective review, only 11 percent of the women had risk factors for macrosomia or shoulder dystocia and among these, none were identified prospectively. Additionally, 91 percent of patients with brachial plexus injury recovered with no sequelae. One instance of brachial plexus injury occurred at the time of cesarean section. These data reveal that macrosomia and subsequent shoulder dystocia cannot be predicted. Therefore, it is not feasible to prevent brachial plexus injury prospectively by prophylactic cesarean section. Great clinical acumen and technical expertise by the obstetrician using a variety of methods may be useful in avoiding, as much as possible, injury to the mother and fetus when shoulder dystocia does occur.


Surgical laparoscopic experience during the first year on a teaching service. Recently, general surgeons have become actively involved in laparoscopic operations. The best method for teaching these techniques to surgical residents is unclear. Since June 1990, at St. Luke's-Roosevelt Hospital Center in New York City, we have instituted a formal course of instruction for surgical residents. This includes a reference syllabus, didactic instruction, use of an inanimate training device and a hands-on practice in swine. Clinically, the residents progress from observer to camera operator and, finally, operator. During the first year of this program, the authors performed 90 laparoscopic cholecystectomies, of which 71 were elective and 19 were for acute cholecystitis. There were seven morbidly obese patients, while 25 had undergone prior abdominal operations. The first 25 operations performed by the authors averaged 93.2 minutes, while the last 40 operations performed primarily by the surgical residents with assistance of the authors averaged 70 minutes. There were nine complications, including postoperative pancreatitis in two patients, Clostridium difficile enterocolitis in two and one each of prolonged paralytic ileus, postoperative transfusion and umbilical incision dehiscence. Two patients had postoperative common duct stones. There were no wound infections, bile duct injuries or deaths. Complications were evenly distributed throughout the series and did not correlate with whether the surgeon was a resident or an attending surgeon. The results of this plan have been quite successful and thus far, 12 residents have completed this program.


Prospective comparison of partial versus total portal decompression for bleeding esophageal varices. Eighty-six patients underwent portacaval shunt (PCS) to treat bleeding esophagogastric varices during a period of four years. Twenty-eight patients (group 1) underwent emergency total portal decompression, while 58 patients (group 2) underwent elective partial PCS. Age, gender, preshunt and postshunt alcohol consumption and modified Child-Pugh classification at the time of operation, and at latest follow-up evaluation, did not differ significantly between the two groups. Early mortality was higher after emergency shunts than after elective operation (p < 0.01). However, partial portal decompression, when compared with total shunt, resulted in a significantly lower likelihood of late mortality (13 versus 39 percent) (p < 0.05), as well as portasystemic encephalopathy (8 versus 56 percent) (p < 0.0005). All shunts remained patent postoperatively and no patient had variceal rebleeding during follow-up evaluation averaging 2.2 years. Duplex sonography demonstrated hepatofugal portal flow in all patients in both groups. The results of the current study suggest that partial portal decompression is technically feasible, prevents further variceal hemorrhage and confers significant protection against late mortality and the development of postshunt neuropsychologic dysfunction.


Cardiovascular changes during laparoscopic cholecystectomy. Although the technique of laparoscopic cholecystectomy has increasing appeal, physiologic data to support the safety of this procedure are lacking. We studied the cardiovascular changes in 16 patients undergoing laparoscopic cholecystectomy, using impedance cardiography as a noninvasive means of continuous monitoring of cardiac output. Serial measurements of mean arterial pressure (MAP), heart rate (HR), intraperitoneal pressure and expired carbon dioxide tension (PECO2) were also recorded. Results revealed a decrease of 30 percent (p < 0.001) in cardiac index and 5 percent (p = 0.089) in HR, along with increases of 15 percent (p < 0.001) in MAP and of 79 percent (p < 0.001) in the calculated total peripheral resistance index. This elevation in afterload could lead to both an increase in myocardial oxygen consumption and to the potential risk of myocardial ischemia and possibly infarction or congestive heart failure, or both, in patients who are susceptible. The data suggest that patients with a history of cardiac disease should have preoperative cardiac evaluation and be closely monitored during laparoscopic cholecystectomy, as in any other extensive operation.


Reassessment of preoperative laboratory testing has changed the test-ordering patterns of physicians. To test the hypothesis that physicians have substantially reduced the ordering of unwarranted preoperative tests, the authors reviewed 2,093 medical records of patients having four surgical procedures performed at three institutions in three cities in 1979, 1981, 1983, 1985 or 1987. Excluding hemoglobin measurements, the incidence of ordering preoperative laboratory tests unwarranted by findings on history or physical examination decreased from 32.2 to 25.9 percent during this decade, representing a 19.6 percent reduction. This decrease was irregular and varied from operation to operation, test to test and institution to institution. Overall, the percentage of preoperative tests ordered that were unwarranted decreased from 66.9 percent in 1979 to 60.1 percent in 1987. Extrapolating these results, the authors estimate that more than $320 million was saved annually by elimination of unwarranted tests and that the potential savings could exceed $1.35 billion a year. Unexpectedly, the preoperative ordering of medically indicated tests also decreased (from 92.9 to 80.9 percent, representing a 12.9 percent reduction). Because the benefit of performing justified tests is probably greater than the benefit of avoiding unwarranted tests, the net change has probably not been beneficial. A better system for obtaining justified tests and for eliminating the unwarranted tests may be necessary before a net benefit occurs. Punitive measures to reduce testing without prior establishment of such a system may save money, but impair health.


Microbiologic factors of stump wound infection. Specimens from 52 patients with stump wound infection (SWI) were studied for aerobic and anaerobic bacteria. Bacterial growth was present in 44 specimens. Only aerobic or facultative bacteria were recovered in 19 specimens, only aerobic bacteria in 12 and mixed aerobic, facultative and anaerobic bacteria in 13. One hundred and three isolates were recovered (2.3 per specimen)-58 aerobic or facultative (1.3 per specimen) and 45 anaerobic (1.0 per specimen). The predominant isolates were anaerobic cocci (17), Bacteroides species (13 isolates), Staphylococcus aureus (12) and Escherichia coli (11). Polymicrobial infection occurred in 36 instances. S. aureus was more commonly isolated and anaerobic bacteria were less commonly isolated in SWI of the arms, compared with legs. These data highlight the polymicrobial aerobic-anaerobic cause of SWI.


The importance of the endopelvic fascia repair during vaginal hysterectomy. During 1985 to 1989, 177 vaginal hysterectomies were performed in the Department of Gynecology, Kaplan Hospital, Rehovot, Israel, using the Porges technique with some modifications. Ninety patients had some degree of loss of the pelvic support--anterior or posterior wall relaxation, enterocele or uterine prolapse in various degrees. The patients were allocated to two groups, in which two different techniques were compared: group 1, with repair of the pubocervical and pararectal fascia and group 2 without the repair. The repair of the pubocervical and pararectal fascia after vaginal hysterectomy prevented vaginal vault prolapse (zero versus 15 percent, p < 0.01) and reduced the incidence of recurrent rectocele (23 versus 55 percent, p < 0.05) and recurrent cystocele (14 versus 45 percent, p < 0.005). Recurrent genuine stress incontinence was found in 9 percent of patients in group 1 and 18 percent of patients in group 2 (not statistically significant; p = 0.163). Optimal management of relaxation of the vaginal wall during vaginal hysterectomy requires clinical suspicion and precise preoperative diagnosis and therapeutic plan. In the present study, the need for careful repair of the pubocervical and pararectal fascia during vaginal hysterectomy to prevent vaginal vault prolapse is emphasized. This procedure does not prolong the operation significantly (92 +/- 15 versus 84 +/- 17 minutes) and has no deleterious postoperative complications.


Immunoperoxidase confirmation of ultrasonically guided fine needle aspirates in patients with recurrent hyperparathyroidism. Fine needle aspiration (FNA) biopsy in conjunction with ultrasonic definition of nonpalpable masses in the neck region is being used more frequently. Currently available preoperative localization tests have failed, in many instances, to delineate adequately the location of missed adenomas of the parathyroid gland. We describe herein the use of ultrasonically guided FNA of parathyroid tissue with immunoperoxidase confirmation for precise localization of the diseased gland. Three patients with persistent hypercalcemia after exploration of the neck were referred to Ochsner Clinic, New Orleans. In two of these patients, a parathyroid adenoma had been removed, while in one patient no adenoma was found. All patients had elevated calcium (range 10.9 to 11.6 milligrams per deciliter), low phosphorous and elevated parathyroid levels. Preoperative ultrasonography to localize the suspected parathyroid glands was performed, with FNA and immunohistochemical confirmation. Smears confirmed adequate cellular material. Alcohol fixed, Papanicolaou stained and air dried, Wright's and Giemsa stained smears were evaluated for the presence of parathyroid cells by conventional cytologic examination. The Papanicolaou-stained slides were then decolorized in 1 percent hydrochloric acid in 70 percent ethanol. After decolorization, the smears were stained for parathyroid hormone (PTH) in an avidin-biotin complex (ABC) system, using a commercially available ABC kit (Vector Laboratories Inc.). The primary antibody is a polyclonal antiserum generated in rabbits against a synthetic human PTH. Negative controls were obtained from normal thyroid glands. In all three patients, the diseased gland was localized by ultrasound with cytologic and immunohistochemical confirmation, one on the right side and two on the left side. At surgical excision, the adenomas weighed 0.8 and 0.75 gram and the carcinoma, 0.75 gram. In two, intraoperative identification of the diseased gland was aided by ultrasound directed methylene blue injection into the adenoma. During a follow-up evaluation of eight to 24 months, serum calcium had remained normal in two patients, and one patient had become hypocalcemic and required calcium supplements. The preoperative localization allowed a direct surgical approach to the side in question in all patients. Ultrasonically guided FNA in an immunoperoxidase system can be a valuable preoperative localization technique for patients with recurrent hyperparathyroidism, thus avoiding extensive exploration of the neck with the subsequent complications.


Local antibiotic prophylaxis in inguinal hernia repair. We compared the effects of single dose (750 milligrams) prophylactic cefamandole delivered directly into the operative wound with local anesthesia (n = 162) with a control group (no antibiotics) (n = 162) in a randomized trial. No adverse effects were observed. There were seven wound abscesses in the untreated group compared with none in the group receiving antibiotic prophylaxis (p = 0.007). Six of the seven abscesses occurred as late as one month after the patient was discharged from the hospital. The costs of antibiotics used were ten times less than the costs of treatment of wound complications in the control group.


A simple modification of choledochoenterostomy using continuous pull through suture. A simple modification of choledochoenterostomy is described. Using continuous suture and pull through technique, the posterior line of the anastomosis is completed without immediate approximation of the two structures. By improving the access, good control of the posterior suture line is ensured, the risk of anastomotic leakage is minimized and the use of stent or T tube is unnecessary.


A new technique for ureteral stent placement during pregnancy using endoluminal ultrasound. Endoluminal sonography using the IVUS is a minimally invasive procedure performed using a flexible 6.2F catheter with a 20 megahertz transducer that can easily be passed endoscopically to image the urethra, bladder, ureter and renal pelvis. In the current study, a woman patient in her third trimester of pregnancy with a renal pelvic stone and persistent colic was safely treated with placement of an indwelling ureteral stent. Because it is minimally invasive and does not require the use of roentgenograms, we believe the IVUS will be a useful tool to assist with the management of ureteral colic in patients who are pregnant in whom intervention is required.


Colonoscopic impaction in left colon strictures resulting in right colon pneumatic perforation. Colonic perforation during flexible colonoscopy is a rare but recognized complication. We reviewed 4,593 colonoscopies performed from 1984 to 1989. The perforation rate for diagnostic colonoscopy was 0.17% (6/3,538) and for therapeutic colonoscopy it was 2% (21/1,055). Four perforations of the right colon occurred at a site proximal to the level of the impacted colonoscope. The lesions being evaluated were obstructive in nature: two diverticular strictures (sigmoid colon), one ischemic stricture (descending colon), and one annular carcinoma (descending colon). The four perforations occurred in the right colon and manifested as distension with pneumoperitoneum or retroperitoneal emphysema. Operative management included total abdominal colectomy in two patients (ileoproctostomy in one and ileostomy in one) and right colectomy in two. Outcome was favorable in all cases.


Correlative histologic and arthroscopic evaluation in rheumatoid knee joints. The correlation between arthroscopic observations and histologic changes in rheumatoid arthritis is still controversial. Synovial samples of 21 knee joints in rheumatoid arthritis patients were comparatively investigated by endoscopy and histology. Biopsies were scored by an endoscopist and subsequently dissected. Different histochemical and immunocytochemical staining techniques were used to define inflammatory activity. Arthroscopic and histological values were compared by rating scales and variance analysis. Our study indicates that synovial biopsy is of diagnostic value in rheumatoid arthritis. However, its usefulness depends on the histochemical methods used. The results revealed highly significant correlations of endoscopic features with the number of neutrophilic granulocytes, intravascular leukocytes, and peroxidase-positive macrophages. However, no relationship was found between the detection of lymphocytes or resident macrophages and inflammatory scores. The close correlation between endoscopic and histological findings suggests that arthroscopic evaluation allows a valuable classification of the inflammatory activity in rheumatoid synovitis.


Laparoscopic tube cholecystostomy.

Laparoscopic tube cholecystostomy. Tube cholecystostomy was offered to 100 patients undergoing laparoscopic cholecystectomy as an alternative to open surgery should the gallbladder be found too severely inflamed for safe removal. At the time of surgery, three of the 100 patients had gallbladders judged too severely inflamed for laparoscopic cholecystectomy. They therefore underwent laparoscopic placement of a cholecystostomy tube. The patients received 48 h of antibiotics in the hospital and then underwent tube drainage for 4-6 weeks as outpatients. They returned to the hospital for interval laparoscopic cholecystectomy. The three patients underwent successful interval laparoscopic cholecystectomy. There were no complications. Of the 100 patients in the study, conversion to open cholecystectomy was not necessary for any of the patients. Tube cholecystostomy is a safe and effective procedure. It should reduce the number of patients who require open surgery for removal of the gallbladder.


Mesenteric venous thrombosis. Modern management and endoscopic diagnosis. Mesenteric venous thrombosis has an obscure etiology, a prolonged onset of symptoms, and controversial methods of diagnosis and treatment. Eleven collected patients with pathologic confirmation of this diagnosis are presented, with one patient demonstrating the endoscopic appearance of this disease in human small bowel. Other methods of diagnosis are also reviewed. Treatment of mesenteric venous thrombosis requires resection of necrotic bowel and, we believe, anticoagulation. The role of planned "second-look" laparotomy is reviewed, but it was not necessary in those patients in whom definitive resection could be combined with intraoperative anticoagulation.


Concomitant placement of percutaneous endoscopic gastrostomy and jejunostomy. Percutaneous endoscopic gastrostomies have gained wide use for long-term enteral nutrition. However, gastroesophageal reflux and aspiration pneumonia have occurred following this procedure. Initial enthusiasm concerning the ability of intrajejunal feeding to negate the risk of aspiration has been challenged by some reports. In this report, a new method is described for concomitant placement of endoscopic gastrostomy and feeding jejunostomy wherein the tip of the feeding jejunostomy is placed at least 40 cm distal to the pylorus while the gastrostomy tube is used for drainage. Twenty critically ill patients underwent the procedure utilizing general or local anesthesia. Sixty-day follow-up showed one uneventful episode of pulmonary aspiration (5%) after retrograde migration of the jejunal tube into the duodenum. All but two patients (90%) tolerated their tube feedings well. This technique can be easily performed with accurate placement of the PEJ tube distal to the pylorus and is associated with minimal risk of aspiration.


Is laparoscopic better than open appendectomy? Laparoscopic appendectomy is becoming increasingly popular as surgeons strive to manage surgical problems via minimally invasive techniques. We reviewed our early experience in 38 patients with laparoscopic appendectomy and compared it to open appendectomies done during the same time period. We found no difference in hospital costs, stay, or wound infection rate. There was a significant difference in OR time: the laparoscopic approach took longer. We conclude that this new approach is not clearly superior to open appendectomy despite theoretical advantages. Newer instruments and further studies are needed.


Diagnostic laparoscopy in critically ill intensive-care-unit patients. The diagnosis of intraabdominal sepsis in critically ill intensive-care-unit patients remains a challenge. Diagnostic laparoscopy has been performed in seven such patients following admission for coronary artery bypass surgery, gram-negative sepsis, major burns, pneumonia, myocardial infarction, and post-pneumonectomy. Laparoscopy revealed acalculous cholecystitis in two patients (one removed laparoscopically), gangrenous colon in two, cirrhosis with liver infarction in one, and, in two patients, no pathology. Although five patients died postoperatively, none was related to the laparoscopy. There were no intraoperative complications and no known pathology was missed. Because of its ease and accuracy, diagnostic laparoscopy should be considered in all critically ill patients suspected of harboring intraabdominal pathology. Further studies are needed to fully establish its efficacy and safety.


Laparoscopic splenectomy--technical aspects. Since the recent development of endoscopic cholecystectomy various other digestive disorders have been treated endoscopically. Using the endo-GIA stapler the authors report a case of laparoscopic splenectomy. Five trocar sheaths were used. Once detached, the spleen was cut into fragments in a plastic bag intraabdominally, which allowed its removal. Splenectomy was performed for a girl who had an autoimmune thrombocytopenic purpura (ITP). No operative transfusion was required. The patient was discharged after an uncomplicated postoperative recovery. The cosmetic result is good.


LaparoLith. A new instrument for stone fragmentation in laparoscopic cholecystectomy. Laparoscopic cholecystectomy can be performed with incisions of a maximum diameter of 10 mm. The removal of a stone-filled gallbladder at the end of an operation via the 10-mm port needs often-extensive tissue-consuming manipulations for stone removal or minilaparotomy. Stone fragmentation can be achieved by mechanical crushing and by ultrasound-, electrohydraulic-, and tunable dye laser lithotripsy. The clinical employment of the LaparoLith (Baxter Healthcare Corporation), an instrument which allows mechanical fragmentation of stones inside the gallbladder, is presented here. We have used the LaparoLith in nine patients and have been successful in stone fragmentation in seven of these. The LaparoLith seems to be helpful in laparoscopic cholecystectomy, preventing extension of the subnavel incision.


Des-gamma-carboxyprothrombin (PIVKA II) and plasma vitamin K1 in newborns and their mothers. Assessments of the vitamin K status in newborns and their mothers by means of des-gamma-carboxy-prothrombin (PIVKA II) measurement have given equivocal results. Part of the variability could be attributed to differences in sensitivity (i.e. the ability to detect small concentrations) and validity (i.e. ability to detect vitamin K deficiency) of the methods applied. None of these methods have yet been validated with respect to plasma vitamin K1. In 22 healthy mother/infant pairs PIVKA II was determined using three different assays including ratio Xa/ecarin (Xa/ec), crossed immunoelectrophoresis (CIE), and an ELISA with a monoclonal antibody (MAB). The results were compared with conventional clotting tests and plasma vitamin K1. The following results were obtained: Cord blood: Clotting tests within age-related normal ranges; PIVKA II detection rates: 0/22 (Xa/ec), 1/22 (CIE), 4/22 (MAB); plasma vitamin K1: undetectable in 20/22. Mothers: Clotting tests all within normal range; PIVKA II detection rates: 1/22 (Xa/ec), 0/22 (CIE), 5/22 (MAB); plasma vitamin K1 (pg/ml) for all mothers (median; range): 186; 55-833; for PIVKA II positive mothers: 213; 59-699. PIVKA II detectability in newborns and mothers was not correlated. The results show an increase in sensitivity for PIVKA II detection in the order of MAB >> CIE > Xa/ec. Due to the very low plasma vitamin K1 at birth, no correlation was possible between cord PIVKA II detectability and plasma vitamin K1. However, in mothers at term PIVKA II MAB appears to be unrelated to the vitamin K status.


Reduction in factor VII, fibrinogen and plasminogen activator inhibitor-1 activity after surgical treatment of morbid obesity. The aim of this study was to determine the effects of the surgical treatment of morbid obesity on some aspects of haemostatic and fibrinolytic function. Measurement of haemostatic and fibrinolytic factors was performed before and again 6 and 12 months after operation in 19 patients suffering from morbid obesity. Surgical treatment resulted in a mean decrease in body weight of 50 kg at 6 months and 64 kg at 12 months. Weight loss was accompanied at 12 months by significant reductions in median (interquartile range) concentrations of serum cholesterol from 5.3 (4.5-6.2) mmol/l to 3.6 (2.9-4.6) mmol/l; factor VII from 113 (92-145)% of normal to 99 (85-107)%; of fibrinogen from 3.5 (3-9.3) g/l to 2.8 (2.4-3.8) g/l; and of plasminogen activator inhibitor-1 (PAI-1) activity from 21 (11-30) IU/ml to 6.3 (5-10) IU/ml. The decrease in PAI-1 activity probably accounted for a significant reduction in euglobulin clot lysis time. Tissue plasminogen activator activity was undetectable in most patients pre-operatively but increased slightly after 1 year to 110 (100-204) mIU/ml. There were no significant changes in plasma levels of KCCT, factor VIII, von Willebrand factor antigen, alpha-2-antiplasmin, antithrombin III, protein C antigen, beta thromboglobulin, platelet factor 4, fibrinopeptide A or platelet count. These findings provide support for the hypothesis that the surgical treatment of morbid obesity may have a long-term beneficial effect on mortality from cardiovascular and thromboembolic disease.


Enhancement of spontaneous fibrinolytic activity in diabetic retinopathy. The fibrinolytic system was studied in 96 patients with type I diabetes mellitus. Patients were grouped according to their degree of retinopathy; 38 patients with no evidence of retinopathy, 28 patients with background retinopathy and 30 patients with proliferative retinopathy. Thirty healthy individuals served as controls. The basal fibrinolytic activity as measured by clot lysis time and t-PA activity was increased in diabetic patients. This was associated with low levels of plasminogen activator inhibitor. Increased levels of D-dimer in diabetic patients further indicate enhanced in vivo fibrinolysis. The increase in fibrinolytic activity was highest in diabetics without retinopathy, and decreased with increasing retinopathy. Endothelial release of t-PA after venous occlusion was not different between controls and all diabetic groups. These findings suggest that in type I diabetics the fibrinolytic system is in an activated state. With worsening of retinopathy this increase in fibrinolytic activity diminishes.


The production of a factor X activator by a methylcholanthrene-induced rat fibrosarcoma. The association between neoplasia and thrombosis has been well documented. We have studied the production of a procoagulant which is a factor X activator in a rat fibrosarcoma model. Extracts of excised tumor were assayed in a one stage clotting assay using normal and factor deficient human plasmas. The activity was not due to tissue factor, as acceleration of clotting was observed in FVII deficient plasma. No activity was noted in FX deficient plasma. The activator was capable of cleaving 125I-FX in the absence or presence of calcium. A radioimmunoassay (RIA) demonstrated a 5,100-fold increase in the levels of FX activation peptide after exposure to sarcoma extract. The FX activation occurs in the absence of calcium although the effect is greatly accelerated in the presence of 5 mM CaCl2. Using a two-stage amidolytic assay, functional activation of FX by the sarcoma was demonstrated. Inhibitor studies suggest that the sarcoma-derived procoagulant is a serine protease. The methylcholanthrene-induced rat sarcoma may serve as a useful model for investigating the regulation and effects of cancer procoagulants.


Multicentric evaluation of a new assay for prothrombin fragment F1+2 determination. A multicenter study of a recently developed ELISA for the determination of prothrombin fragment F1+2 was performed in order to evaluate analytical and clinical aspects. Mean intra-assay and inter-assay reproducibility were found to be 11.0 and 12.6%, respectively. The measuring range covered by the calibration curve reaches from 0.04 to 10.0 nM/l F1+2. Testing 133 healthy subjects a reference range of 0.37 to 1.11 nM/l F1+2 (2.5-97.5 percentile) with a median of 0.66 nM/l F1+2 was calculated. Minor difficulties with blood sampling (venous occlusion for 2 min) did not affect F1+2 plasma concentrations. Significantly increased F1+2 levels were measured in patients with leukemia (p < 0.0001), severe liver disease (p < 0.005) and after myocardial infarction (p < 0.01). Elevated F1+2 concentration before the beginning of heparin therapy (1.25 nM/l) decreased to 0.77 nM/l (p < 0.0001) after 1 day of therapy. For patients in the stable phase of oral anticoagulant therapy decreasing F1+2 concentrations were measured with increasing INR. F1+2 levels were already significantly reduced in patients with INR < 2.0 (0.56 nM/l; p = 0.0005). Thus F1+2 determination may be helpful in identifying activation processes as well as in monitoring anticoagulant therapy.


Influence of the xanthine derivate HWA 138 on endotoxin-related coagulation disturbances: effects in non-sensitized vs D-galactosamine sensitized rats. We have evaluated the effects of the xanthine derivate HWA 138 in rat endotoxemia in order to 1) prevent coagulation disturbances and other endotoxin-induced physiological abnormalities and 2) to reduce mortality. We performed two studies using two different models (sensitized vs non-sensitized rats) with a similar mortality but different severity of coagulation disturbances: a) LPS (15 mg/kg) alone or with HWA 138 (80 mg/kg) as a treatment modality 30 min pre LPS, b) galactosamine (500 mg/kg) simultaneously with LPS (100 micrograms/kg) with or without HWA 138 (80 mg/kg) pretreatment. Experiments c) and d) employed D-galactosamine and/or LPS similar to experiments a) and b), while HWA 138 was applied simultaneously. We found significant 1) amelioration of life-threatening coagulation disturbances in non-sensitized rats, 2) prevention of liver dysfunction in sensitized rats, 3) reduction of TNF formation in both models, and 4) improvement of survival in all groups receiving HWA 138. Our data indicate protective effects of HWA 138 against clotting disturbances either directly via reduced LPS-induced formation of procoagulant activity or indirectly via reduced TNF formation.


Prevention of thrombus growth by antithrombin III-dependent and two direct thrombin inhibitors in rabbits: implications for antithrombotic therapy. We compared the abilities of heparin and two direct thrombin inhibitors to prevent fibrin accretion onto pre-existing thrombi in rabbits. Inhibition of thrombus growth was measured as the ability of each test compound to inhibit the accretion of 125I-fibrin onto thrombi pre-formed in jugular veins of rabbits. When administered as a continuous infusion, the two direct (i.e. antithrombin III-independent) thrombin inhibitors, r-hirudin and a tripeptide, Ac(D)-Phe-Pro-bor-Arg (P-8714) inhibited fibrin accretion as effectively as heparin, but did so in doses which generated little systemic anticoagulation, as compared to the marked anticoagulation associated with the heparin effect. However, both r-hirudin and P-8714 were more effective when they were administered as a single bolus injection than as a continuous infusion. Under the former conditions, there was only a transient systemic anticoagulant effect. We conclude that direct or antithrombin III-independent thrombin inhibitors are more effective than heparin in preventing thrombus growth. The limited effect of heparin is likely due to fibrin impairing the ability of heparin/antithrombin III to inactivate thrombin.


Collaborative study of a proposed international standard for plasma fibrinogen measurement. There is increased interest in the relationship between plasma fibrinogen levels and the incidence of coronary artery disease. The National Institute for Biological Standards and Control (UK) has completed a study to establish an International Standard for plasma fibrinogen. This study was conducted using a recommended assay procedure to measure the clottable material present in the proposed lyophilised Standard (coded 89/644). Twenty-two laboratories from nine countries took part in the study and analysis of the data allowed the calibration of 89/644 at 2.4 mg/ml clottable protein. Agreement with this figure was established in two laboratories using three or more different assays for plasma fibrinogen. Degradation studies of the proposed plasma fibrinogen Standard suggested that no loss of clottable protein was observed when the lyophilised material was stored at 20 degrees C for 1 year. The Fibrinogen Sub-Committee of the ISTH (Amsterdam, The Netherlands, June 1991) supported the establishment of 89/644 as an International Standard. This collaborative study will be presented to the Expert Committee on Biological Standardisation of the World Health Organisation at their 1992 session. In the meantime 89/644 will be distributed as the proposed International Standard for plasma fibrinogen measurement containing 2.4 mg/ml clottable protein.


Pharmacokinetic properties of recombinant factor VIII compared with a monoclonally purified concentrate (Hemofil M). The Recombinate Study Group. A recombinant FVIII preparation, Recombinate, was compared with a high-purity plasma-derived concentrate, Hemofil M, in 47 hemophilia A patients in a cross-over evaluation of pharmacokinetic properties. The recombinant material showed a significantly lower clearance, volume of distribution, and higher in vivo recovery, but a similar half-life to the plasma-based product. In a comparison with reported data from other standard concentrates, the recombinant preparation exhibited potentially better pharmacokinetic properties in that its clearance was slower and its half-life was longer. We conclude that the recombinant DNA method of preparation does not adversely affect the biological and pharmacological characteristics of the factor VIII molecule.


The hemodynamic and fibrinolytic response to low dose epinephrine and phenylephrine infusions during total hip replacement under epidural anesthesia. Lower rates of deep vein thrombosis have been noted following total hip replacement under epidural anesthesia in patients receiving exogenous epinephrine throughout surgery. To determine whether this is due to enhanced fibrinolysis or to circulatory effects of epinephrine, 30 patients scheduled for primary total hip replacement under epidural anesthesia were randomly assigned to receive intravenous infusions of either low dose epinephrine or phenylephrine intraoperatively. All patients received lumbar epidural anesthesia with induced hypotension and were monitored with radial artery and pulmonary artery catheters. Patients receiving low dose epinephrine infusion had maintenance of heart rate and cardiac index whereas both heart rate and cardiac index declined significantly throughout surgery in patients receiving phenylephrine (p = 0.0001 and p = 0.0001, respectively). Tissue plasminogen activator (t-PA) activity increased significantly during surgery (p < 0.005) and declined below baseline postoperatively (p < 0.005) in both groups. Low dose epinephrine was not associated with any additional augmentation of fibrinolytic activity perioperatively. There were no significant differences in changes in D-Dimer, t-PA antigen, alpha 2-plasmin inhibitor-plasmin complexes or thrombin-antithrombin III complexes perioperatively between groups receiving low dose epinephrine or phenylephrine. The reduction in deep vein thrombosis rate with low dose epinephrine is more likely mediated by a circulatory mechanism than by augmentation of fibrinolysis.


The anatomical distribution of plasma fibrinolytic activity in man during cardiac catheterisation. Regional circulating plasma levels of fibrinolytic activity were assessed in 15 patients undergoing cardiac catheterisation. The euglobulin clot lysis time (ECLT) was longer in the abdominal aorta (AA) than the inferior vena cava (IVC), (median difference -17.5 min, p = 0.008). This was associated with higher inhibition of plasminogen activator activity (PAI) in the AA than IVC, -1.75 IU/ml, p = 0.002. In the venous circulation the ECLT was higher in the peripheral venous sample than in the IVC, -25.5 min, p = 0.003, with higher PAI peripherally than in the IVC, -1.9 IU/ml, p = 0.001. There were no differences in ECLT, PAI, PAI-1:Ag or t-PA:Ag throughout the arterial circulation. These results demonstrate higher fibrinolytic activity with lower inhibitor activity in the venous compared to the arterial circulation. Within the venous circulation fibrinolytic activity is lower peripherally with increased inhibitor activity.


Mutations in severe, type III von Willebrand's disease in the Dutch population: candidate missense and nonsense mutations associated with reduced levels of von Willebrand factor messenger RNA. The von Willebrand factor (vWF) genes of nine unrelated, severe, type III von Willebrand's disease (vWD) patients (six of Dutch origin) and four unrelated Dutch type I vWD patients were screened for mutations in exons that contain CGA codons (Arg), which are liable to mutation to TGA stop codons. The nine exons of the vWF gene (3, 8, 9, 10, 28, 31, 32, 43 and 45) that contain all the CGA codons (11 in total) of the vWF cDNA were amplified by the polymerase chain reaction and screened for mutations by single-strand conformation polymorphism analysis, restriction enzyme - and/or nucleotide sequence analysis. Three of the severe vWD patients were found to be heterozygous for a nonsense mutation: CGA Arg 2535-->TGA Stop. Three other severe vWD patients were homozygous for a single nucleotide substitution, AAC Asn 2546-->TAC Tyr. The transcription of these mutated alleles was tested by cDNA dependent amplification of platelet RNA. The level of transcription product was strongly reduced for either mutant allele.


Comparison of the inhibitory effects of the TXA2 receptor antagonist, vapiprost, and other antiplatelet drugs on arterial thrombosis in rats: possible role of TXA2. The antithrombotic effect of the thromboxane A2 receptor antagonist, vapiprost, was compared with those of other antiplatelet drugs using an arterial thrombosis model which utilized photochemical reaction in the rat femoral artery. Vapiprost prolonged the time required to occlude the artery with thrombus and inhibited collagen-induced rat platelet aggregation in whole blood ex vivo, in a dose-dependent manner. The potency ranking of antithrombotic effect was vapiprost > ketanserin (serotonin 5-HT2 receptor antagonist) >> ticlopidine (inhibitor of ADP-induced platelet aggregation) = dipyridamole (adenosine uptake inhibitor) > aspirin (cyclooxygenase inhibitor). On the other hand, the ranking of antiplatelet effect was ticlopidine > or = vapiprost > or = aspirin. Ketanserin and dipyridamole were ineffective. Relative to their antiplatelet effect, vapiprost and ketanserin had powerful antithrombotic effects. It is possible that the potent antithrombotic effects of vapiprost and ketanserin in vivo reflect the ability of these drugs to inhibit mediator-induced vascular contractions in addition to platelet aggregation. The results of the present study also suggest that TXA2 may play an important role in thrombogenesis in rats.


Hereditary protein C-deficiency: laboratory values in transmitters and guidelines for the diagnostic procedure. Report on a study of the SSC Subcommittee on Protein C and Protein S. Protein C Transmitter Study Group. A multicenter study on protein C-antigen and -activity values was carried out in transmitter patients with hereditary protein C deficiency (diagnosis established by pedigree analysis) and in normal controls in order to (1) establish the range of protein C levels in genetically determined heterozygotes and (2) to evaluate the usefulness of statistical procedures to discriminate between protein C deficient patients and controls. In transmitters absolute protein C activity values ranged from 19 to 82% and antigen values from 22 to 88.5%. Most transmitter patients could clearly be differentiated from the control group. However, in some transmitter patients values of protein C were within the range of the control group. The discrimination between transmitters and controls could be improved by statistical procedures. Using tolerance ellipses the overlapping area of the two groups was smallest when (factor II antigen+factor X antigen)/2 was plotted against protein C antigen. To specify the degree of uncertainty likelihood ratios were calculated to obtain the posterior probability for an individual for being deficient or not. In quadratic discriminant analysis the best discrimination between transmitters and controls was obtained using protein C activity versus factor X antigen and protein C antigen versus factor X antigen. Based on these analysis an equation was derived, which allows the calculation of the likelihood ratio favouring deficiency or non-deficiency in an individual.


PPACK-thrombin is a noncompetitive inhibitor of alpha-thrombin binding to human platelets. Recent studies from our laboratory indicate that purified kininogens are noncompetitive inhibitors of human alpha-thrombin but not PPACK-thrombin, binding to human washed platelets. In order to understand the mechanism by which the kininogens inhibit alpha-thrombin binding, investigations were initiated to determine if alpha-thrombin and PPACK-thrombin bound to the same site on human platelets. Initial investigations reveal that alpha-thrombin is a more potent inhibitor of 125I-PPACK-thrombin binding than PPACK-thrombin. Further studies show that PPACK-thrombin is a noncompetitive inhibitor of 125I-alpha-thrombin binding to platelets. These studies suggest that human alpha-thrombin binds on the platelet surface to a different site or binds differently to the same site from PPACK-thrombin. These data indicate that the ability of the kininogens to block alpha-thrombin binding to platelets but not PPACK-thrombin binding results from these thrombins having either two different binding sites or one binding site on the platelet surface which they interact with differently.


Kinetics of merthiolate-induced aggregation of human platelets. Incubation of human platelet-rich plasma (PRP) or washed platelets with merthiolate (MT; sodium ethylmercurithiosalicylate; an inhibitor of lysophosphatide: arachidonoyl transferase) leads to irreversible platelet aggregation which is parallelled by an increase in thromboxane A2 synthesis. MT-induced aggregation is preceded by a pronounced lag-period (0.5-10 min). Duration of the latter is inversely related to the concentration of MT ([MT]). Platelet responses to MT are similar to those triggered by arachidonate (AA) in that the relationships of the aggregation rates both to [MT] and [AA] are threshold and exhibit characteristic super-high values of the apparent Hill coefficients (h > 30). A typical MT-induced response can be subdivided in two sequential phases: i) cyclooxygenase-independent slow aggregation, and ii) indomethacin-abrogated rapid aggregation. MT-induced responses are blocked by PGE1 or ajoene (which inhibits binding of fibrinogen to its cell surface receptor, GPIIb/IIIa). The obtained data are interpreted both quantitatively and qualitatively in terms of a model assuming the existence of: i) a relationship between the rate of MT-inhibitable AA incorporation into phospholipids and the concentration of intracellular free AA, [AA]i; ii) a certain threshold value of [AA]i essential for triggering the second phase of the aggregation.


Binding of annexin V to a human ovarian carcinoma cell line (OC-2008). Contrasting effects on cell surface factor VIIa/tissue factor activity and prothrombinase activity. Proteins of the annexin/lipocortin family bind tightly to anionic phospholipids and platelets and act as in vitro anticoagulants. Annexins may be useful as tools to study the availability of anionic phospholipids on cell surfaces and their role in the regulation of blood coagulation. In the present study, we investigated the binding of annexin V (placental anticoagulant protein I) to a human ovarian carcinoma cell line, OC-2008, that constitutively expresses surface membrane tissue factor activity. Binding of annexin V to cell monolayers was calcium-dependent, specific, saturable and reversible; Scatchard analysis indicated a single class of binding sites with an apparent Kd of 9.4 +/- 3.1 nM and 5.2 +/- 1 x 10(6) sites per cell. Binding was completely inhibited by phospholipid vesicles containing phosphatidylserine, but was not inhibited by vesicles containing phosphatidylcholine. Annexin V inhibited the cell surface-dependent activity of prothrombinase complex, but did not inhibit the activity of the factor VIIa/tissue factor complex. In conclusion, these results suggest that anionic phospholipid is present on the extracellular face of OC-2008 cells; this anionic phospholipid is functionally important for the activity of the prothrombinase complex, but the importance of anionic phospholipid for the cell surface factor VIIa/tissue factor functional activity is unclear.


The inhibitory effect of 9-amino-1,2,3,4-tetrahydroacridine (THA) on platelet function. Tetrahydroacridine (THA), or Cognex, is currently awaiting FDA approval for the treatment of Alzheimer's disease. In addition to reports indicating that THA improves the symptoms of patients with Alzheimer's disease, we have found that THA possesses potent antiplatelet activity. THA produced dose-dependent inhibition of human platelet aggregation induced by collagen, ADP, A23187, and phorbol ester. THA, when added to activated platelets, dispersed the platelet aggregates. We have also examined the effects of THA on intracellular Ca++ mobilization, ATP release, and production of cyclic AMP.


1-Deamino-8 D-arginine vasopressin decreases the production of 13-hydroxyoctadecadienoic acid by endothelial cells. 1-Deamino-8 D-arginine vasopressin (DDAVP) has been used effectively to normalize the bleeding time in various hemostatic disorders. In von Willebrand disease the reduction in bleeding time is due to the preferential release of large multimers of von Willebrand factor from endothelial cells. However, since the bleeding time correction in patients with uremia and liver disease is independent of the release of von Willebrand antigen and activity, other mechanisms of action of DDAVP need to be considered. Endothelial cells generate several thromborepellant factors including 13-hydroxyoctadecadienoic acid (13-HODE), an inhibitor of platelet adhesion to subendothelium. Using cultured fetal bovine aortic endothelial cells (FBAECs), we have investigated whether DDAVP modulates the production of 13-HODE. We have demonstrated that 14C-linoleic acid labeled FBAECs release several oxygenated derivatives of linoleic acid following a 120 min incubation in the presence of serum. One of these products was identified by chromatographic procedures as 13-HODE. The production of 13-HODE was decreased significantly by DDAVP (1-100 ng/ml) with maximal reduction (approx. 25%) seen at 1 ng/ml of DDAVP. While vehicle treated control FBAECs generated 6780 +/- 690 cpm of 13-HODE per 10(6) cells (mean +/- SE, n = 8), DDAVP treated FBAECs produced 4950 +/- 310 (P < 0.01), 5390 +/- 390 (P < 0.01), and 5720 +/- 410 cpm (P < 0.05) of 13-HODE at 1, 10, and 100 ng/ml DDAVP respectively. Our findings of a decrease in 13-HODE would explain the previously observed morphologic changes of increased platelet adhesion to subendothelium following DDAVP infusion and contributes to our understanding of the mode of action of this therapeutic agent in hemostatic disorders.


The acute effect of a single very high dose of N-3 fatty acids on coagulation and fibrinolysis. The objective of the study was to investigate the acute effect of a single very high dose of n-3 PUFA on coagulation and fibrinolysis. Forty healthy volunteers were randomized into two groups to receive either 20 grams of n-3 PUFA or 20 grams of n-6 PUFA as a single dose at 6 p.m. with their evening meal. Coagulation and fibrinolysis were evaluated in the fasting state at 8 a.m. the next morning and compared to values obtained at 8 a.m. the day before, when the participants were on their habitual diets. PAI-1 activity in plasma increased by a mean of 62% in subjects randomized to receive n-3 PUFA despite that no changes could be demonstrated in t-PA antigen levels. PAI-1 activity was unaltered in the 20 controls receiving n-6 PUFA. Plasma fibrinogen, coagulation factor VII, thrombin-antithrombin complexes and D-dimer did not significantly change after either supplement. The substantial increase in levels of PAI-1 activity in plasma after a single very high dose of n-3 PUFA may limit the usefulness of single very high doses of n-3 PUFA in acute clinical conditions.


The vascular plasminogen activator as source of the fibrinolytic potential observed during cardiopulmonary bypass. Increased fibrinolytic activity is a well recognized constant finding observed during cardiopulmonary bypass (CPB). The purpose of the present work was to study and estimate the factors involved in the plasminogen activation and prekallikrein-kallikrein systems in a population of adult patients undergoing open heart surgery with CPB. Plasminogen activator activity determinations with a fibrinolytic method as well as plasminogen activation and prekallikrein-kallikrein determinations with synthetic substrates were carried out. Our results indicate that no active fibrinolysis but a fibrinolytic potential, similar to that observed in blood obtained after venous occlusion, can be demonstrated in circulating plasma during CPB. This fibrinolytic potential is related to the presence of vascular plasminogen activator released from endothelial cells by the CPB stimulus.


Molecular mechanism of hemolymph clotting system in Limulus. Limulus (horseshoe crab) hemolymph is known to be very sensitive to bacterial endotoxin (LPS), which causes a rapid coagulation response. Hemolymph contains a single type of hemocyte that undergoes aggregation, adhesion, and degranulation in response to LPS. The granule contents are released into the hemolymph, where they form an insoluble gel. We have characterized four components involved in this coagulation response that comprise a cascade of three serine protease zymogens (factor C, factor B, and proclotting enzyme) and one clottable protein (coagulogen). Of these components, factor C sensitive to LPS is a protein composed of five complement-related domains ("Sushi" or SCR), an EGF-like domain, and a C-type lectinlike domain as well as a putative amino-terminal LPS-binding domain. This domain structure is very similar to that of selectin family of cell adhesion molecules, suggesting that it might also function as a cell adhesion molecule after the release into the hemolymph. Factor B and the proclotting enzyme share a common Cys-rich motif ("cliplike" domain) in the amino-terminal portions. This domain is also found in a putative serine protease zymogen ("easter") in Drosophila, which is essential for normal embryonic development. All four of the components of the cascade and an antibacterial protein (anti-LPS factor) are localized to a specific type of the hemocyte granule. Another antibacterial peptide (tachyplesins I and II) is localized in a distinct granule population. The contents of both granule populations are released into the hemolymph in response to LPS, where they cooperate in immobilization and killing of Gram-negative bacteria.


Low dose infusion of adenosine diphosphate prolongs bleeding time in rats and rabbits. The effect of intravenous infusion of adenosine diphosphate (ADP) on haemostatic and thrombotic mechanisms was studied in rats and rabbits. Infusion of ADP (0.2-1 microMol/kg/min) in rabbits prolonged the skin capillary bleeding time threefold after between 1/2 and 2 hours of infusion. Prolongation of the bleeding time was parallelled by reduced in vitro sensitivity of platelets to ADP in citrated platelet-rich plasma. No major changes in respiratory frequency and heart rate were observed. On the other hand, infusion of adenosine (1 microMol/kg/min) did not affect the bleeding times. Intravenous ADP (0.1 microMol/kg/min) significantly prolonged the bleeding time in anaesthetized rats. Platelet and red cell counts before and during the ADP infusion indicated slight, reversible platelet aggregation. After 75 min the ratio between red cells and platelets resumed a steady pre-experimental level. Platinum wires placed in the abdominal aorta of rats to monitor thrombus formation during ADP infusion indicated an antithrombotic effect of prolonged, low dose infusion of ADP. Since infusion of adenosine did not affect the haemostatic mechanisms, these observations may indicate that ADP infusion desensitized the platelet responsiveness to aggregating stimuli in vivo, and/or that prostacyclin production by endothelium was stimulated by infusion of ADP.


Different effects of A23187 and PMA on palmitoylated platelet proteins. The effect of agonists on palmitoylated proteins was examined in platelets prelabeled with [3H]palmitic acid. Non-reduced gels revealed major labeled proteins with masses from 30-38 kDa. One of these proteins was modified by A23187, which led to a loss of radioactivity, and PMA, which altered its electrophoretic mobility. A possible link between the A23187-induced loss of label associated with the protein and the activation of calpain was suggested by the following experiments. (1) There was a good correlation between the loss of label and the proteolysis of proteins in A23187-activated platelets. (2) The permeant calpain inhibitor, E64d, blocked the loss of label as well as the proteolysis of proteins. (3) The loss of label also occurred in a Triton lysate, where calpain was known to be activated. The effect of PMA on the palmitoylated protein was observed only in prelabeled platelets. The protein kinase inhibitor, staurosporine, abolished the PMA-induced platelet aggregation as well as the mobility shift of the labeled protein.


Thrombin-induced shape change in human megakaryoblastic leukemic cells, MEG-01, is mediated by protein kinase C. We investigated the intracellular processes of the shape change in human megakaryoblastic leukemic cells, MEG-01, by platelet agonists. Thrombin induced the formation of many pseudopods. This shape change was also induced by phorbol 12-myristate 13 acetate (TPA) and weakly by Ca2+ ionophore, A23187, but not by ADP, collagen, or epinephrine. Electron microscopy and FITC-labeled phalloidin staining revealed thick submembranous microfilament bundles in the pseudopods of the shape-changed cells by thrombin. Shape change was inhibited by cytochalasin B. Since Ca(2+)-dependent phosphorylation reactions play central role on the initiation of shape change of platelet, we examined the effects of protein kinase C (PKC) inhibitor, H-7, and myosin light chain (MLC) kinase inhibitor, ML-9, on the shape change of MEG-01 cells induced by thrombin, and observed that H-7 potently inhibited thrombin-induced shape change, while ML-9 did not. These results suggest that thrombin-induced reorganization of microfilaments and shape change of MEG-01 cells are mediated by PKC, but not by MLC kinase.


[Historical perspective on growth hormone treatment in children]. The history of growth hormone treatment can be divided into two episodes. Between 1958 and 1985 growth hormone was extracted from human pituitaries. Because of the scarcity little scientific research was carried out and efficacy was not optimal. In 1985 biosynthetic growth hormone became available, which facilitated research on the use of growth hormone for various indications. In the future further research is needed on the pathophysiology of growth disturbances, on methods to improve efficacy, and on possible side-effects of pharmacological dosages.


[Good things come in small packages? Psychosocial aspects of small stature]. Short stature is considered as a social disadvantage. This review deals with the findings of studies on cognitive and socio-emotional functioning in children with growth hormone deficiency, constitutional short stature, Turner syndrome, skeletal dysplasias and chronic illnesses. The consequences of short stature in adulthood are also described. The short term effect of growth hormone treatment on psychosocial functioning appears positive, but long term results have to be awaited before conclusions can be drawn.


[Turner syndrome: a virtually certain indication for growth hormone treatment]. Short stature is a feature in almost all cases with Turner syndrome. The etiology is unknown, but GH secretion appears to be normal. The treatment with anabolic steroids does not seem to increase final height. Oestrogens are needed for secondary sex characteristics, but should be given in a low dosage and at approximately 12-13 years of age, in order not to compromise final height. Growth hormone increases growth velocity and leads to an average gain of 5 cm in terms of final height. The addition of oxandrolone leads to an even higher growth rate, but final height is probably similar to that reached by growth hormone alone. The dosage, injection frequency, age and bone age at the start of therapy have influence on the efficacy. GH in the dosages given appears safe.


[Growth hormone treatment in short stature of unknown origin]. Most children with idiopathic short stature can be classified under the diagnoses familial short stature and constitutional delay of growth and adolescence. Administration of growth hormone leads to faster growth, but also faster bone maturation. Daily injections are more efficacious than three injections per week. There is a dose-response relationship. In a Dutch prospective study, the acceleration of growth was only slightly more than bone age advance, so that the average predicted adult height increased only by 3 cm over a period of 4-5 year. In an untreated control group final height was 1 cm lower than predicted. There were great inter-individual differences in terms of growth and bone maturation, which could not be predicted on the basis of clinical and biochemical variables.


[Intra-uterine growth retardation: an indication for treatment with growth hormone?]. Children with intra-uterine growth retardation (IUGR) constitute a heterogeneous group. Classification and etiology of IUGR are given. This report presents data on postnatal growth, growth hormone (GH) secretion and GH-therapy in children with short stature after IUGR, which was not based on a chromosomal disorder or a syndrome, with exception of Silver-Russell Syndrome (SRS). During the first two years of life, 86% of the children with IUGR showed spontaneous catch-up growth to a height above the third percentile, while only 14% did not. Sixty to eighty percent of the children with poor catch-up growth showed an insufficient GH-secretion, despite of the fact that most children did not show the typical, clinical characteristics of children with classical growth hormone deficiency. GH-therapy leads to increased growth velocity, but so far only short-term results have been reported. No serious adverse events were observed. The individual growth responses were heterogeneous, but no difference was shown in the response between the sexes or between those with or without SRS. It is still unclear whether GH-therapy will improve final height and which factors enable detection of patients who will most likely benefit from GH-therapy. Only long-term clinical trials until final height will answer those questions.


[Chronic kidney insufficiency: results of treatment with growth hormone]. Stunted growth is a serious problem for many children with chronic renal insufficiency (CRI). Dialysis does not improve growth velocity, while renal transplantation does not always result in better growth either. The pathogenesis of the growth retardation is unknown, but growth hormone (GH) secretion and plasma levels of insulin-like growth factors (IGF) I and -II appear to be normal. Elevated levels of IGF-binding proteins may be involved in the growth retardation. Several 2-year studies have shown that impressive increase in growth velocity can be achieved with GH therapy with 28 IU/m2/week, without significant changes in renal function or adverse events. A lower GH dose of 14IU/m2/week was not able to maintain catch-up growth for longer than 6 months in children older than 4 years. Bone maturation appears unaffected, suggesting improved final height. In children with CRI GH-treatment is best started following 1 year of marked growth retardation. Preliminary results of GH-treatment in children after renal transplantation seem promising, but long-term data are needed before definitive conclusions can be drawn.


[Growth hormone therapy in dysmorphic syndromes and chronic disease]. Many clinical syndromes are associated with short stature, which can be proportionate or disproportionate. In the first group of syndromes, such as Turner syndrome and its variants, Down syndrome, Prader-Willi-Labhart syndrome, Noonan syndrome, and Silver-Russell syndrome growth hormone therapy can lead to increased growth velocity, but so far only short-term results have been reported. Growth hormone is contraindicated in syndromes with an increased risk of chromosomal breakage, e.g. Bloom syndrome. In disproportionate syndromes, such as hypochondroplasia, pseudopseudohypoparathyroidism, spina bifida, and hypophosphataemic rickets, the results of growth hormone therapy are not encouraging. Growth hormone therapy in children with rheumatoid arthritis and thalassaemia appears little effective. Long-term clinical trials of reasonable size are needed before reliable conclusions can be drawn about the value of growth hormone therapy in these conditions.


Synthetic approaches toward total synthesis of 12 beta-methyl- and 12-methylene-19-norpregnanes. The effect of a substituent in the 12-position of progestagens was studied. To this end, various approaches toward the preparation of 12 beta-alkyl- and 12-alkylidenenorpregnanes were investigated. Eventually, the desired compounds 17 beta-hydroxy-12 beta-methyl-18a-homo-19-nor-17 alpha-pregn-4-en-20-yn-3-one (37) and 17 beta-hydroxy-12-methylene-18a-homo-19-nor-17 alpha-pregn-4-en-20-yn- 3-one (38) were obtained in racemic form by total synthesis; they were shown to lack progestagenic activity.


Synthesis of N-acetylglucosaminides of unconjugated and conjugated bile acids. 3-N-Acetylglucosaminides of unconjugated, glycine- and taurine-conjugated bile acids have been synthesized. Bile acids appropriately protected were condensed with acetochloroglucosamine through the 3 alpha-hydroxyl group by means of the Koenigs-Knorr reaction using cadmium carbonate as a catalyst. Subsequent borohydride reduction and/or alkaline hydrolysis provided desired 3-N-acetylglucosaminides of unconjugated bile acids. Glycine-conjugates were obtained from N-acetylglucosaminides of unconjugated bile acids and ethyl glycinate by the carbodiimide method. The preparation of N-acetylglucosaminides of taurine-conjugates was attained by the Koenigs-Knorr reaction of bile acid p-nitrophenyl esters followed by condensation with taurine. 7-N-Acetylglucosaminides of ursodeoxycholates were prepared in a similar fashion. The convenient synthesis of 3-N-acetylglucosaminides of unconjugated bile acids is also described.


Synthesis of deuterium-labeled 5 alpha-androstane-3 alpha, 17 beta-diol and its 17 beta-glucuronide. Using unlabeled androsterone as starting material, 5 alpha-[16,16-2H2]androstan-3 alpha-ol-17-one was synthesized by exchange using deuterated potassium methoxide. This labeled androsterone product was reduced by sodium borodeuteride, which gave predominantly trideuterated 5 alpha-androstane-3 alpha, 17 beta-diol. The labeled androstanediol was conjugated with glucuronide by using the Koenig-Knorr reaction with methyl-1-bromo-1-deoxy-2,3,4-tri-O-acetyl-alpha-D-glucopyranosuronate . The dominant product was identified by thermospray high-performance liquid chromatography/mass spectrometry (MS) and electrospray MS as 5 alpha-[16,16,17-2H3]androstane-3 alpha, 17 beta-diol, 17 beta-glucuronide.


17-Epimerization of 17 alpha-methyl anabolic steroids in humans: metabolism and synthesis of 17 alpha-hydroxy-17 beta-methyl steroids. The 17-epimers of the anabolic steroids bolasterone (I), 4-chlorodehydromethyltestosterone (II), fluoxymesterone (III), furazabol (IV), metandienone (V), mestanolone (VI), methyltestosterone (VII), methandriol (VIII), oxandrolone (IX), oxymesterone (X), oxymetholone (XI), stanozolol (XII), and the human metabolites 7 alpha,17 alpha-dimethyl-5 beta-androstane-3 alpha,17 beta-diol (XIII) (metabolite of I), 6 beta-hydroxymetandienone (XIV) (metabolite of V), 17 alpha-methyl-5 beta-androst-1-ene-3 alpha,17 beta-diol (XV) (metabolite of V), 3'-hydroxystanozolol (XVI) (metabolite of XII), as well as the reference substances 17 beta-hydroxy-17 alpha-methyl-5 beta-androstan-3-one (XVII), 17 beta-hydroxy-17 alpha-methyl-5 beta-androst-1-en-3-one (XVIII) (also a metabolite of V), the four isomers 17 alpha-methyl-5 alpha-androstane-3 alpha,17 beta-diol (XIX) (also a metabolite of VI, VII, and XI), 17 alpha-methyl-5 alpha-androstane-3 beta,17 beta-diol (XX), 17 alpha-methyl-5 beta-androstane-3 alpha,17 beta-diol (XXI) (also a metabolite of V, VII, and VIII), 17 alpha-methyl-5 beta-androstane-3 beta,17 beta-diol (XXII), and 17 beta-hydroxy-7 alpha,17 alpha-dimethyl-5 beta-androstan-3-one (XXIII) were synthesized via a 17 beta-sulfate that spontaneously hydrolyzed in water to several dehydration products, and to the 17 alpha-hydroxy-17 beta-methyl epimer. The 17 beta-sulfate was prepared by reaction of the 17 beta-hydroxy-17 alpha-methyl steroid with sulfur trioxide pyridine complex. The 17 beta-methyl epimers are eluted in gas chromatography as trimethylsilyl derivatives from a capillary SE-54 or OV-1 column 70-170 methylen units before the corresponding 17 alpha-methyl epimer. The electron impact mass spectra of the underivatized and trimethylsilylated epimers are in most cases identical and only for I, II, and V was a differentiation between the 17-epimers possible. 1H nuclear magnetic resonance (NMR) spectra show for the 17 beta-methyl epimer a chemical shift for the C-18 protons (singlet) of about 0.175 ppm (in deuterochloroform) to a lower field. 13C NMR spectra display differences for the 17-epimeric steroids in shielding effects for carbons 12-18 and 20. Excretion studies with I-XII with identification and quantification of 17-epimeric metabolites indicate that the extent of 17-epimerization depends on the A-ring structure and shows a great variation for the different 17 alpha-methyl anabolic steroids.


Studies of the synthesis of biomarkers. XI. Synthesis of 4,5-secocholestane and 4-methyl-4,5-secocholestane. 4,5-Secocholestane (1a) and 4-methyl-4,5-secocholestane (1b) were synthesized from cholesterol (2) in five and seven steps, respectively. The key intermediate, 5-oxo-4,5-secocholestan-4-al (7) was reduced by the Clemmensen method to afford 1a. Meanwhile, 7 underwent selective Wittig reaction, Clemmensen reduction, and hydrogenation to give another target molecule, 1b. The structure of an unknown biomarker was shown to be different from the proposed 1a by gas chromatographic and mass spectrometric comparison.


Application of time-series analysis for the recognition of increases in urinary estrogens as markers for the beginning of the potentially fertile period. Time-series analysis was applied to the urinary total estrogen data from 142 ovulatory menstrual cycles to determine the first statistically significant increase as a marker for the beginning of the potentially fertile phase. Application of the Trigg's tracking signal to each cycle detected an increase in urinary total estrogens above the baseline in every case, with a cumulative probability of > or = 95%. The distribution of first increase days ranged from 10 days before 3.5 days before the presumed day of ovulation with a mean of 6.5 +/- 1.4 days. The significant parameters in the calculation of the tracking signal are the smoothing constant (alpha) which is related to the number of baseline observations, the baseline mean for the cycle, and the variation of the baseline mean. The method allows a calculation of the tracking signal as the cycle unfolds and a statistical assessment can be given each day. The procedure is easily adaptable for computer calculation, and because it is applied to individual cycles avoids the use of population means with the loss of information inherently associated with the combination of data from many cycles. The Trigg's tracking signal is an appropriate method of analysis of menstrual cycle data and represents a satisfactory alternative to the more usual cumulative sum procedure. The distribution of the first increases constitutes a reference standard for urinary estrogen assays.


H-1, C-13, and F-19 nuclear magnetic resonance assignments of 3,3-difluoro-5 alpha-androstane-17 beta-ol acetate. The molecular structure of 3,3-difluoro-5 alpha-androstane-17 beta-ol acetate was analyzed by 1H, 13C, and 19F nuclear magnetic resonance (NMR) techniques; two-dimensional NMR was used to assigned 1H and 13C resonances. The 1H NMR spectrum in deuterated chloroform shows three sharp singlets (delta = 0.74, 0.79, and 2.00 ppm) integrating for three protons each, an isolated triplet at 4.55 ppm integrating for one proton, and overlapping multiplets between 0.72 and 2.12 ppm integrating for 31 protons. The 13C spectrum shows 18 resonances between 10 and 55 ppm, and three additional resonances at 82.9, 124.0, and 171.5 ppm. The 19F[1H] spectrum shows two sets of doublets (observed 2J = 150 Hz) at 5.00 and -4.80 ppm. Multiplets arising from 19F-13C J-coupling provide the starting assignment for all resonances by means of 1H homonuclear correlation (COSY) and 1H-13C heteronuclear correlation spectroscopy.


Marked increase of stroke incidence in men between 1972 and 1990 in Frederiksberg, Denmark. Stroke incidence declined until the end of the 1970s in the United States, and the decline continued into the 1980s in Japan. The purpose of this study was to determine possible temporal changes of stroke incidence in a European community. A prospective stroke registry was established in the community of Frederiksberg (population, approximately 90,000), Denmark, in the two periods 1972-1974 and 1989-1990. All patients suspected of stroke were clinically evaluated by a neurologist. Only patients with first-ever stroke were included. Complete case ascertainment was ensured by registration of both hospitalized and nonhospitalized patients. Death certificates were also scrutinized. A total of 927 patients with first-ever stroke was recorded. The annual stroke incidence rate per 1,000 increased by 18% from 2.6 in 1972-1974 to 3.1 in 1989-1990 (p < 0.01). This increase was due solely to a 42% increase in men, in whom stroke incidence rose from 2.1 to 3.0 (p < 0.0005). Incidence was unchanged in women at 3.0 and 3.1, respectively. The incidence rates from 1972-1974 were age and sex adjusted to the 1990 population. After adjustment to the Danish population, stroke incidence in Denmark was 2.0 for all, 2.3 for men, and 1.9 for women. In the second study period computed tomography or necropsy was performed in 85% of cases; 2.4/1,000 had cerebral infarction; 0.20/1,000 had intracerebral hemorrhage; and 0.02/1,000 had subarachnoid hemorrhage. In a period when decline in stroke incidence has stopped in the United States and has continued in Japan, a marked increase of stroke incidence in Danish men was observed.


Prevalence and determinants of carotid atherosclerosis in a general population. The aim of this study was to assess the prevalence of asymptomatic carotid atherosclerotic lesions and their relation to principal risk factors. The importance of the relation between asymptomatic carotid atherosclerotic lesions, stroke, and coronary atherosclerosis has been widely discussed, but there are few transversal and longitudinal studies on a general population. A noninvasive examination was carried out using high-resolution B-mode ultrasonography, which has been shown to be a reliable tool for epidemiological studies. We examined 630 men and 718 women aged 18-99 years (participation rate, 74.9%). The global prevalence of carotid atherosclerosis was 25.4% in men and 26.4% in women. Intimal-medial thickening was found in 9.4% of men and 11.7% of women. Plaque prevalence was 13.3% in men and 13.4% in women; prevalence of stenotic plaques was 2.7% and 1.5%, respectively. Subjects aged < or = 39 years showed a very low prevalence of any asymptomatic carotid atherosclerotic lesions. In the multiple logistic regression, the analysis of subjects aged > or = 40 years showed a positive significant association between the severity of carotid atherosclerotic lesions (plaques and stenosis) and age (p < 0.001), systolic blood pressure (p < 0.01), cigarette smoking (p < 0.0001), and the protective effect of high density lipoprotein cholesterol (p < 0.037). This analysis did not provide evidence of a clear-cut association between risk factors and intimal-medial thickening. This population study shows the high prevalence of asymptomatic carotid atherosclerotic lesions in a general population (approximately 25% of adults) and its relation with the classic risk factors. It emphasizes the value of ultrasonography in the detection of early atherosclerotic lesions.


Incidence and prognosis of stroke in the Valle d'Aosta, Italy. First-year results of a community-based study. We sought to determine the incidence rate, risk factors, and prognosis of stroke in Valle d'Aosta, Italy, to provide information for planning regional health-care facilities. We undertook a prospective study of all new cases of stroke in the geographically defined population of 114,325 residents of Valle d'Aosta in northern Italy. In the first year of the study (January 1-December 31, 1989), 254 cases of first stroke were registered. The crude annual incidence rate was 2.23/1,000, 1.98/1,000 for men and 2.46/1,000 for women. After adjustment to the 1988 Italian population, the incidence rate for first stroke was 2.15/1,000 per year, 2.48/1,000 per year for men and 1.99/1,000 per year for women. The pathological diagnosis was cerebral infarction in 67%, intracranial hemorrhage in 15%, and unknown in 18%. The overall 30-day case-fatality rate was 31%. In survivors, Barthel Index Score recorded at 30 days from stroke onset showed that 100 patients (62%) were dependent in activities of daily living. Our results do not differ significantly from those reported in Umbria, the only similar study performed in Italy, and support non-Italian data as to risk factors in stroke.


Longitudinal study of regional cerebral blood flow changes in depression after stroke. We studied 60 patients longitudinally to examine relations between regional cerebral blood flow and depressive states after stroke. Poststroke depressive states were assessed by the Zung Self-Rating Depression Scale (SDS). Regional cerebral blood flow was measured using the 133xenon inhalation method with patients in the resting state on the same day as the SDS assessment. All patients were followed for an average of 14 months after the initial assessment. Severity of depression was inversely correlated with regional cerebral blood flow values in the parieto-occipital regions of the right hemisphere and in the anterior temporal region of the left hemisphere at the initial evaluation. Patients with lesions in left frontal or right parieto-occipital regions were more depressive in comparison with those with other brain lesions. Follow-up study showed significant inverse correlations between changes in SDS score and changes in regional cerebral blood flow at all scalp sites. Furthermore, higher inverse correlations were observed at specific brain regions in each hemisphere, including the parietal and parieto-occipital regions of the right hemisphere and the anterior temporal and inferior frontal regions of the left hemisphere. This relation was independent of recovery from neurological deficits. These results suggest that dysfunction of specific cortical and subcortical regions in both hemispheres asymmetrically contributes to depressive state after stroke.


Ticlopidine versus aspirin for the prevention of recurrent stroke. Analysis of patients with minor stroke from the Ticlopidine Aspirin Stroke Study. Ticlopidine has not been formally compared with aspirin in patients with a completed stroke. We therefore performed an analysis on a subgroup of patients from the Ticlopidine Aspirin Stroke Study (TASS) with a recent minor completed stroke as the qualifying ischemic event. This was a multicenter, double-blind, randomized trial of patients with a recent history of cerebral ischemia. Eligible patients had a qualifying minor stroke within 3 months of study entry. All patients received either 650 mg aspirin twice daily or 250 mg ticlopidine twice daily for up to 5.8 years. The primary study end point was the first occurrence of nonfatal stroke or death from any cause. A secondary end point was the first occurrence of a fatal or nonfatal stroke. Minor stroke was the qualifying ischemic event in 927 patients (463 received ticlopidine and 464 received aspirin). The cumulative event rate at 1 year for nonfatal stroke or death was 6.3% for patients receiving ticlopidine and 10.8% for patients receiving aspirin, a 42% risk reduction in favor of ticlopidine. For fatal or nonfatal stroke, the cumulative event rate at 1 year was 4.8% for patients receiving ticlopidine and 7.5% for those receiving aspirin, a risk reduction of 36% for ticlopidine relative to aspirin. The overall risk reductions were 22.1% for nonfatal stroke or death and 19.9% for fatal or nonfatal stroke. Adverse reactions were reported in 58% of the ticlopidine patients and 51% of the aspirin patients. The results in this subgroup are consistent with the overall TASS results and show that ticlopidine is somewhat more effective than aspirin for reducing the risk of stroke in patients with a completed minor stroke.


Cerebral blood flow velocity after hyperventilation-induced vasoconstriction in hypertensive patients. The aim of our study was to evaluate by transcranial Doppler ultrasonography the dynamics of blood flow velocity changes in the middle cerebral artery during and after hypocapnia-induced vasoconstriction in untreated essential hypertensive patients. Sixteen hypertensive patients (10 men and six women, 29-62 years of age) and 10 healthy control subjects (six men and four women, 30-62 years of age) were studied. Patients with mild-to-moderate essential hypertension (mean +/- SE blood pressure, 171/106 +/- 3/2 mm Hg) belonged to stage I or II of the World Health Organization classification. Mean blood flow velocity in the middle cerebral artery, arterial blood pressure, and end-tidal CO2 partial pressure were recorded at baseline, during 2-minute hyperventilation, and every 30 seconds up to 5 minutes after hyperventilation. End-tidal CO2 partial pressure values overlapped in the two groups throughout the study. Baseline values of mean blood flow velocity in hypertensive patients were similar to those in normotensive subjects (mean +/- SE values, 64.7 +/- 3.9 cm/sec versus 58.6 +/- 3.7 cm/sec). A similar fall in mean blood flow velocity was observed in hypertensive patients and normotensive subjects (43.2 +/- 2.8% versus 46.7 +/- 3.6%). Mean blood flow velocity reverted to baseline more quickly in hypertensive patients: 1.5 minutes after hyperventilation, mean blood flow velocity was 60.7 +/- 3.1% and 84.9 +/- 1.8% of control in normotensive subjects and hypertensive patients, respectively. No changes in arterial blood pressure were observed in either group throughout the study. This study demonstrates that the recovery of blood flow velocity in the middle cerebral artery after hyperventilation is faster in hypertensive patients than in normal subjects, thus providing further evidence that chronic hypertension is associated with changes in the dynamics of cerebral blood vessel reactivity.


99mTc-HMPAO-SPECT with acetazolamide challenge to detect hemodynamic compromise in occlusive cerebrovascular disease. Insufficiency of collateral supply may lead to low-flow infarcts in severe occlusive cerebrovascular disease. The aim of this study was to evaluate the feasibility of technetium-99m-labeled hexamethylpropyleneamine oxime (99mTc-HMPAO) single-photon emission computed tomography (SPECT) to assess hemodynamic compromise in the anterior circulation. Cerebral blood flow before and after 1 g acetazolamide was analyzed by 99mTc-HMPAO-SPECT in 21 symptomatic patients with documented extracranial obstructions. SPECT findings were correlated with the results of angiography, transcranial Doppler sonography, and computed tomographic scan. The acetazolamide-induced increase of cerebral blood flow could be reliably monitored by increase of cerebral 99mTc-HMPAO uptake, which varied between 11.4% and 47.6% in the less-affected hemisphere. Increment of hemispheric side-to-side asymmetry of tracer uptake after drug challenge revealed significant restriction of regional vasoreactivity in 11 patients. Agreement in assessing hemodynamic compromise was reached in 81% of patients with ophthalmic artery collaterals on angiography (p < 0.001), in 76% with low-flow infarcts on computed tomographic scan (p < 0.01), and in 91% with markedly reduced flow velocities on transcranial Doppler (p < 0.0001). One patient developed a low-flow infarct in the area predicted by SPECT during follow up. We conclude that 99mTc-HMPAO-SPECT with acetazolamide challenge is a useful method for assessment of the adequacy of hemispheric collateral pathways in patients with severe occlusive cerebrovascular disease.


Critical limits of pressure-flow relation in the human brain. This study was designed to determine the minimal mean flow velocity and pressure-flow relation necessary to preserve human consciousness. Passive upright tilt provocation was used in conjunction with transcranial Doppler in 80 patients with a history of syncope of unknown etiology. Cerebral blood flow velocity, blood pressure, and heart rate were monitored noninvasively. Forty patients remained asymptomatic, and the rest had clinically induced true syncope or premonitory symptoms. In the asymptomatic group, there was a 23 +/- 16% (p = 0.000) drop in mean flow velocity, but no significant changes in systolic and diastolic blood pressures. In the symptomatic patients, there was a 58 +/- 14% (p = 0.000) drop in mean flow velocity, 37 +/- 23% (p = 0.000) fall in systolic pressure, and 31 +/- 20% (p = 0.000) fall in diastolic pressure. In 80% of symptomatic patients, the critical lower limit of mean flow velocity was at -50% of resting baseline while patients were lying supine. The symptomatic group had lower mean flow velocity and blood pressure responses as compared with the asymptomatic group. The slope and intercept values of the pressure (y axis) to flow velocity (x axis) regression curves indicate a greater degree of impaired autoregulation in the symptomatic group (y = 0.529 x-6.11, r2 = 0.108, p = 0.038) as compared with the asymptomatic (y = 0.317 x + 0.966, r2 = 0.14, p = 0.017). The critical lower limit of cerebral perfusion lies at 50% below baseline supine mean flow velocity.


Features on initial computed tomography scan of infarcts with a cardiac source of embolism in the NINDS Stroke Data Bank. The lack of valid criteria for the clinical diagnosis of cardiogenic embolism is a major problem in both patient care and research. The aim of this study was to identify features on the initial computed tomogram of the brain that discriminate between patient groups with and without a cardiac source of embolism. To gain insight into the neuroradiological features relevant to the diagnosis of cardiac embolic stroke, we studied the initial computed tomogram of the 1,267 patients with ischemic stroke and such a scan in the National Institute of Neurological Disorders and Stroke (NINDS) Stroke Data Bank. We analyzed the initial computed tomographic data from 1,267 patients with ischemic stroke in the NINDS Stroke Data Bank. Based solely on the presence of cardiac sources of embolism, we defined groups with high (n = 244), medium (n = 165), and low (n = 858) risk for cardiogenic embolism and compared the features on the initial computed tomogram among these three groups. Patients in the high-risk group were significantly more likely (p < 0.001) to have infarcts involving one half lobe or larger or infarcts involving both superficial and deep structures than patients in the medium- or low-risk groups. In contrast, deep small infarcts had a negative association (p = 0.004) with the presence of a cardiac source of embolism. There was no significant trend across risk groups in the percent with hemorrhagic infarction, regardless of whether patients with anticoagulant use at the time of the stroke were excluded. Although some features of the initial computed tomogram had highly significant associations with the presence of a cardiac source of embolism, the predictive value of these features for an embolic source was low.


Distribution and correlates of sonographically detected carotid artery disease in the Cardiovascular Health Study. The CHS Collaborative Research Group. This article describes the prevalence of extracranial carotid atherosclerosis assessed by ultrasonography, its association with risk factors, and its relation to symptomatic coronary disease and stroke in men and women aged > or = 65 years. Maximum percent stenosis, maximum common carotid artery wall thickness, and maximum internal carotid artery wall thickness were assessed using duplex ultrasound in 5,201 men and women aged > or = 65 years in the Cardiovascular Health Study, a study of the risk factors and natural history of cardiovascular disease in the elderly. Existing coronary disease and stroke were assessed by physical examination and participant history. Detectable carotid stenosis was present in 75% of men and 62% of women, although the prevalence of > or = 50% stenosis was low, 7% in men and 5% in women. Maximum stenosis and maximum wall thickness measurements increased with age and were uniformly greater at all ages in men than in women (p < 0.00001). Established risk factors for atherosclerosis (hypertension, smoking, diabetes) and indications of vascular disease (left ventricular hypertrophy, major electrocardiographic abnormality, bruits, and history of heart disease or stroke) related to all three carotid artery measures in the elderly. Of the three ultrasound measures, the best correlate for a history of coronary disease was maximum internal carotid artery wall thickness. For stroke the best correlate was common carotid artery wall thickness. Multiple logistic regression models of prevalent coronary heart disease and stroke that included the ultrasound findings indicated, after adjustment for age and sex, that maximum internal wall thickness and maximum common carotid wall thickness were significant correlates of both. Maximum stenosis did not add significantly to the correlation. In the elderly the incidence of carotid atherosclerosis was high, although the frequency of severe disease was low. The prevalence and severity of carotid atherosclerosis continued to increase with age even in the late decades of life, and more disease was found in men than in women at all ages. Known risk factors for atherosclerosis continued to relate to carotid abnormalities in the later decades of life, both in symptomatic and asymptomatic subjects.


Thrombotic occlusion of the middle cerebral artery. Epidemiological study of middle cerebral artery occlusion is important because the indication for extracranial-intracranial arterial bypass remains in dispute. To help clarify this issue, we investigated the prognosis of thrombotic middle cerebral artery occlusion in Japanese patients. We studied 40 patients with thrombotic middle cerebral artery occlusion who were selected on the basis of clinical features, computed tomographic findings, and angiographic findings. Patients with causes of embolism (i.e., cardiomyopathy, valvular heart disease, cardiac arrhythmia, and carotid ulceration) were excluded. The 40 patients were classified into three groups according to the site of middle cerebral artery occlusion: there were 13 patients with occlusion of the proximal portion of the M1 segment, 13 with distal M1 segment occlusion, and 14 with occlusion of the M2 segment. Good collateral circulation was associated with improved outcomes both clinically and by computed tomography in patients with occlusion of the proximal and distal portions of the M1 segment but not in those with M2 occlusion. It is reasonable to assume that not only collateral circulation but also the site of occlusion plays an important role in the outcome of middle cerebral artery occlusion. Our finding that good collateral circulation improves the outcome for thrombotic occlusion of the proximal and distal M1 segments supports the possible benefits of such surgery.


Arginine vasopressin V1-antagonist and atrial natriuretic peptide reduce hemorrhagic brain edema in rats. Injection of arginine vasopressin into the cerebral ventricles in animals with brain injury increased brain water, whereas injection of atrial natriuretic peptide reduced water content. Therefore, to determine the role of endogenous arginine vasopressin in brain edema, we attempted to inhibit edema from a hemorrhagic lesion with an arginine vasopressin V1 receptor antagonist or atrial natriuretic peptide. Adult Sprague-Dawley rats with hemorrhages induced by 0.4 IU bacterial collagenase were treated with 75 ng (n = 9) or 8 micrograms (n = 9) of the vasopressin V1 receptor antagonist d(CH2)5Tyr(Me)Arg, 3.2 micrograms (n = 4) atrial natriuretic peptide injected intracerebrally, or 5 micrograms/kg per hour (n = 7) atrial natriuretic peptide intraperitoneally. They were compared with control groups injected with 0.4 IU collagenase only. Brain water and electrolytes were measured 24 hours later. Brain uptake of [14C]sucrose was measured 30 minutes after lesions were induced by 0.4 IU collagenase alone (n = 5) or after collagenase injection and 50 micrograms/kg per hour (n = 5) atrial natriuretic peptide injected intravenously. The arginine vasopressin V1 receptor antagonist and atrial natriuretic peptide significantly (p < 0.05) reduced water and sodium contents in the posterior edematous regions. Brain uptake of [14C]sucrose was significantly reduced by intravenous atrial natriuretic peptide. Antagonists to arginine vasopressin V1 receptors and atrial natriuretic peptide both significantly reduce hemorrhagic brain edema, and atrial natriuretic peptide appears to protect the blood-brain barrier.


Insulin-induced normoglycemia improves ischemic outcome in hyperglycemic rats. Hyperglycemia is known to aggravate ischemic brain damage. This study sought to determine if preischemic insulin-induced normoglycemia would improve outcome in hyperglycemic rats. Normal rats and rats with 5-7 days of streptozotocin-induced diabetes were studied. Normal rats served as either fasted normoglycemic controls or dextrose-infused (hyperglycemic) controls. In the acutely diabetic rats either no insulin was given or insulin was given at 30 or 90 minutes before ischemia so as to induce preischemic normoglycemia. All rats underwent 10 minutes of forebrain ischemia. After 5 days of recovery, motor function and histological outcome were assessed. Untreated diabetic rats and dextrose-infused control rats had greater hippocampal CA1 damage than normoglycemic control rats. In contrast, insulin-treated diabetic rats had less hippocampal CA1 damage than either untreated diabetic rats or dextrose-infused control rats. Injury in the two insulin-treated groups was not significantly different from that in the normoglycemic control group (all three groups had plasma glucose values of 120-150 mg/dl immediately prior to ischemia). Despite similar plasma glucose values (300-400 mg/dl), fewer postischemic seizures (0% versus 67%) were observed in the untreated diabetic group than in the dextrose-infused control group (p < 0.001). Hyperglycemia caused by either dextrose infusion or streptozotocin-induced diabetes resulted in exacerbated ischemic brain damage. Insulin therapy to rapidly induce preischemic normoglycemia improved outcome from forebrain ischemia in the acutely diabetic rats. Glucose-infused hyperglycemic rats frequently exhibited postischemic generalized seizures while acutely diabetic rats did not. The latter results implicate some adaptive/protective mechanism associated with acute streptozotocin-induced diabetes that results in a decreased sensitivity to hyperglycemia-augmented ischemic brain damage.


Selective brain cooling during and after prolonged global ischemia reduces cortical damage in rats. Studies of the cerebroprotective effects of selective brain cooling have failed to show amelioration of ischemic injury in the cerebral cortex. This study was designed to test the hypothesis that mild-to-moderate selective brain cooling initiated after the onset of global brain ischemia in rats protects the cerebral cortex and improves neurological outcome. Global forebrain ischemia for 30 minutes in 27 fasted adult male Wistar rats was achieved by bilateral carotid occlusion and hypotension. In group 1, brain temperature, measured in the temporalis muscle, was maintained at 37-38 degrees C throughout the experiment. In group 2, brain temperature fell spontaneously during ischemia to 34.7 +/- 0.1 degrees C and rose spontaneously to 36-37 degrees C after 10 minutes of recirculation. In group 3, brain temperature was lowered with ice packs placed around the head after 15 minutes of ischemia to 24.1 +/- 0.9 degrees C by the end of ischemia, maintained at 30.0 +/- 1.0 degrees C for the first hour of recirculation, then allowed to rise to 36-37 degrees C. Seven-day survival was 0% (0 of 6) in group 1, 73% (8 of 11) in group 2, and 100% (6 of 6) in group 3. Severity of neuronal damage was less in group 2 than in group 1 in the cortex (p < 0.05) and hippocampal CA1 (p < 0.05) and CA3 regions (p < 0.05). Group 3 had less neuronal damage than group 2 in both cortex (p < 0.02) and striatum (p < 0.02). Furthermore, postischemic weight loss was less and neurobehavioral scores were significantly higher in group 3. This study shows that selective brain cooling increases survival from prolonged global ischemia and reduces neuronal injury in the cerebral cortex as well as the striatum and hippocampus.