Crystallization of the cpn60/cpn10 complex ('holo-chaperonin') from Thermus thermophilus. A stable complex of the chaperonins, cpn60 and cpn10 (Escherichia coli GroEL and GroES homologues), from the extremely thermophilic bacterium Thermus thermophilus has been isolated and crystallized. The crystals have dimensions up to 30 x 200 x 200 microns. Ultra-thin sections of the crystals estimated by electron microscopy showed a rectangular lattice with unit cell parameters of a = 17 nm, b = 27 nm, gamma = 90 degrees.


Cell cycle kinetics, tissue transglutaminase and programmed cell death (apoptosis). Studies were undertaken on a highly metastatic hamster fibrosarcoma cell line with a view to assessing whether cells entering into apoptosis, measured by counting the number of transglutaminase mediated detergent insoluble envelopes, has any synchrony with a particular phase of the cell cycle. A double exposure of thymidine was used to block cells in early S-phase. Flow cytometry in combination with [3H]thymidine incorporation into DNA was used to assess the degree of synchrony and progression through the different phases of cell cycle. The apoptotic index was found to be at its maximum in mid-S-phase. Measurement of transglutaminase activity in each phase of the cell cycle indicated that the specific activity was also at its greatest during mid S-phase. The level of enzyme was relatively unchanged throughout the cell cycle indicating that the regulation of transglutaminase activity occurs primarily through effects on catalytic activity rather than enzyme synthesis.


Isolation, sequencing and expression in E. coli of the urocanase gene from white clover (Trifolium repens). The urocanase gene was detected in a clone obtained from a genomic library of white clover. The entire gene has been sequenced and expressed in the pT7-7/E. coli BL 21 (DE 3) system. The deduced sequence of the plant urocanase is 72% homologous with that of the well-characterized urocanase from Pseudomonas putida. The purification procedure, as well as kinetic and electrophoretic behaviour, of the new enzyme are described.


N-acetylaspartylglutamate acts as an agonist upon homomeric NMDA receptor (NMDAR1) expressed in Xenopus oocytes. The electrophysiological effects of N-acetylaspartylglutamate (NAAG), an endogenous peptide restrictively distributed in the central nervous system, were studied using Xenopus oocytes injected with RNAs transcribed from cloned glutamate receptor cDNAs. NAAG induced an inward current, dose dependently, in oocytes injected with RNA for an N-methyl-D-aspartate receptor subunit (NMDAR1). In contrast, the oocytes injected with RNAs for AMPA-selective glutamate receptors (GluR1, GluR3, GluR1+GluR2 and GluR2+GluR3) scarcely responded to NAAG, and the oocytes injected with RNA for kainate receptor (GluR6) did not respond to NAAG. The half-maximal response (ED50) value of NAAG on expressed NMDAR1 was 185 microM, which shows that NAAG is about 115-times less potent than L-glutamate (Glu), the ED50 of which value was 1.6 microM. The maximal current amplitude induced by NAAG was about 70% of that by Glu. NAAG-induced current in NMDAR1-injected oocytes was potentiated by glycine, dose-dependently antagonized by DL-2-amino-5-phosphonovaleric acid, and blocked by magnesium ions in a voltage-dependent fashion. These results suggest that NAAG is one of the endogenous agonists selective for NMDAR1.


Transluminal angioplasty of the aorta, renal and mesenteric arteries in Takayasu arteritis: report of two cases. Two patients with Takayasu arteritis presented with either severe renovascular hypertension or profound weight loss due to intestinal angina. The leading clinical signs were cured by successful percutaneous transluminal angioplasty (PTA) of the abdominal aorta and renal arteries in one patient and of the superior mesenteric artery and coeliac trunk in the second. These results and a literature review of the topic suggest that PTA should be the first therapeutic approach in symptomatic arterial stenoses due to TA in the inactive stage of the disease.


Margin configuration, die spacers, fitting of retainers/crowns, and soldering. This article focuses on different margin configurations and the criteria they must meet to be considered clinically successful. In addition, the use of die spacers to lessen the cement film thickness to achieve a better marginal adaptation of cast restorations is presented. Also, the article presents a step by step method for fitting crowns or retainers in the laboratory and in a clinical setting to make this important procedure less time consuming, more precise, and easy to finalize. Finally, soldering in dentistry and the criteria required for its successful execution are discussed.


Pelvic surgery, reproductive factors and risk of ectopic pregnancy: a case controlled study. A case controlled study among 361 women with surgically treated ectopic pregnancy and 420 women delivered at term was designed, aiming at characterization of the association among previous pelvic operations, selected reproductive factors and ectopic pregnancy. All types of previous pelvic operations increase the risk of ectopic pregnancy from a 2-fold increase for appendectomy to a 9-fold increase for ectopic pregnancy, if maternal age, parity, history of spontaneous and induced abortions and history of infertility is controlled. This study suggests that a previous pelvic operation may increase the risk of ectopic pregnancy.


Nonsurgical treatment of ectopic pregnancy. Expectant management and medical treatment of ectopic pregnancy either systemically or locally are reviewed. Because of the risks of tubal rupture, this nonsurgical management should be done with utmost care. To date, surgical removal of an ectopic pregnancy remains the method of choice and this can be safely done by laparoscopy. Alternate treatments should be carefully evaluated in clinical trials.


Trends in postabortal mortality and morbidity in Ibadan, Nigeria. Illegally induced abortion at the University College Hospital, Ibadan increased steadily over a 10-year period (1980-1989) despite increasing availability of family planning services. Abortion was the commonest cause of death in the gynecology service during the period of the study and constituted 36.6% of fatalities. The majority of patients (76.2%) did not accept contraceptives. Almost one-third of the illegal terminations were performed by physicians. Although the percentage of deaths decreased, the contribution of physicians to these fatalities increased, and accounted for 6/9 (66.7%) of fatalities in 1989. This circumstance probably signifies a defect in physician training and ability to perform abortion aftercare. Physicians should be trained in abortion care and laws changed in conjunction with greater drive to improve contraceptive utilization and reduce the incidence of unsafely induced abortion.


Different effects of growth hormone-releasing hormone (GRH) and somatostatin on growth hormone and stable metabolite of prostaglandin E2, 13, 14-dihydro-15-keto-prostaglandin E2 (PGE2-M) in normal subjects. Twenty four healthy subjects were placed in two treatment groups: 1. The first group consisted of twelve subjects in whom growth releasing hormone (GRH) (1 microgram/kg.BW) resulted in a marked and sustained elevation of serum growth hormone (GH) and a slight and delayed increase in plasma prostaglandin E2-M. In the second group, consisting also of twelve subjects, somatostatin infusion (500 micrograms/250 ml) was initiated and maintained for 60 min. Serum GH significantly decreased at 30 and 60 min during infusion and 15 min thereafter. We did not observe any changes in plasma prostaglandin E2-M during or after somatostatin infusion. The results obtained confirm previous in vitro studies and suggest a possible link between growth releasing hormone and prostaglandin E2 in their action on growth hormone secretion. It seems that somatostatin does not play a role in the control of prostaglandin E2 release.


Mullerian adenosarcoma of the uterus in adolescents. A case of uterine Mullerian tumor in an adolescent is described. Surgical and clinical management is discussed, based on the experience gained by the analysis of cases described in the literature. A review of the different age groups, primary sites, surgical management and biological behavior of cases described in the literature is tabulated and analysed.


Antimicrobial therapy for gynecologic infections. ACOG Technical Bulletin Number 153--March 1991. Therapeutic antimicrobial regimens for pelvic infections must provide coverage for aerobic streptococci, common gram-negative enteric bacilli, and anaerobic organisms. Careful attention must be given to antibiotic choice as well as the dose and duration of therapy. The judicious use of a brief perioperative course of antimicrobial prophylaxis is effective in preventing infection following certain gynecologic surgical procedures.


Pregnancy in hemoglobin sickle cell patients at the University College Hospital, Ibadan. A retrospective review of pregnancy outcome in hemoglobin (Hbsc) patients managed at the University College Hospital, Ibadan over a 5-year period (1984-1988) was carried out. The main antenatal complications included anemia (51.2%), bacterial infection (22.0%), bone pain crisis (7.3%) and preeclampsia (2.4%). Intrapartum complications included anemia (29.2%), bone pain crisis (12.2%) and pseudotoxemia (4.9%). The maternal and perinatal mortality rate were 48 and 195 per 1000, respectively. The duration of labor and operative delivery rate were not different from the general population.


Fetal binocular distance as a predictor of menstrual age. The relation between fetal binocular distance and menstrual age was determined by cross-sectional analysis of 555 normal fetuses (14-40 weeks) using real-time sonography. Mathematical modelling of the data demonstrated that the binocular distance growth curve, similar to the biparietal diameter, is nonlinear. Predicted binocular values at various points in gestation were comparable to the results of other investigators. Predicted menstrual age in weeks for specific binocular distance measurements in millimeters were calculated and are reported in tabular form. The variability (+/- 2 SD) associated with predicting menstrual age from binocular distance is +/- 14 days between 14 and 27 weeks, but between 29 and 40 weeks the variability is +/- 24 days. Binocular distance can be used as an adjunct in estimating menstrual age and may be useful in the diagnosis of some abnormalities, e.g. hypotelorism or hypertelorism.


A randomized controlled trial of valethamate bromide in acceleration of labor. A randomized controlled study of valethamate bromide administered by intramuscular injection in acceleration of labor was done in 60 consecutive primigravidae and 60 consecutive multigravidae admitted in labor at 2-4 cm cervical dilatation. There was no difference observed in the rate of cervical dilatation between those who received valethamate bromide and those who received normal saline. However, maternal tachycardia was observed in significantly more women primigravida RR 1.97, 95% CI 1.3-3.0; multigravida RR 2.16, 95% CI 1.3-3.6) who had received valethamate bromide.


Amniotic fluid turbidity: a useful adjunct for assessing fetal pulmonary maturity status. A rapid, very simple technique for establishing fetal pulmonary maturity status is presented. Among 100 receiving amniocenteses, aspiration of turbid amniotic fluid that would not permit the reading of newsprint through it was associated with a lecithin/sphingomyelin (LS) ratio of greater than or equal to 2.0, or the presence of phosphatidyl glycerol (PG) in 97% (specificity 98%, positive predictive value 97%). The authors conclude that when turbid fluid is aspirated, delay until LS and PG results are known may not be necessary.


The midgestational human fetal pancreas contains cells coexpressing islet hormones. In the fetal development of the mouse pancreas, endocrine cells have been found that express more than one hormone simultaneously. Our objective was to evaluate the existence of such cells in the human fetal pancreas. We found cells coexpressing two of the major pancreatic hormones (insulin, glucagon, and somatostatin) in sections of eight midgestational (12-18 weeks) pancreata and in 0-7% of cells in single-cell suspensions from midgestational pancreata. By electron microscopy, using granule morphology and immunoelectron microscopic techniques, we could confirm these findings and even detect cells containing three hormones. Morphologically different granules contained different immunoreactivities, suggesting parallel regulation of hormone production and packaging. In six newborn pancreata (born after 22-40 weeks of gestation), we could not find any multiple-hormone-containing cells. Subsequently, we evaluated whether multiple-hormone-containing cells proliferate by using pancreatic fragments and single-cell preparations at the light and electron microscopic level (six pancreata). No endocrine hormone-containing cells incorporated bromodeoxyuridine during a 1-hr culture period, indicating that these cells have lost the ability to proliferate under the conditions chosen. We conclude that, as in mice, the human fetal pancreas of 12-18 weeks of gestation contains endocrine cells that express multiple hormones simultaneously. These (multiple) hormone-containing cells do not seem to proliferate under basal conditions.


Ultrastructural studies of the ontogeny of fetal human and porcine endocrine pancreas, with special reference to colocalization of the four major islet hormones. Most, if not all, endocrine cells seem capable of synthesizing and storing more than one hormone. Such cellular colocalization of hormones can be due either to the presence of two or more specific granules within the cells or to colocalization of the hormones within a single granule. The present study was performed to clarify the subcellular localization of insulin, glucagon, somatostatin, and pancreatic polypeptide within the endocrine cells of the human and porcine pancreas during fetal development, with special reference to possible colocalization of the hormones. The tissue specimens were processed for ultrastructural cytochemistry using Lowicryl as embedding medium. An immunogold labeling technique was used with two parallel, but not interacting, antibody chains. Sections from each specimen were double labeled in different combinations giving a complete covering of the four major islet hormones. During fetal life (50-90 days prenatally in porcine pancreas, 14 weeks gestation in the human pancreas) several hormones were demonstrated, not only in the same endocrine cells, but also in the same secretory granules (polyhormonal granules). Costorage of insulin, glucagon, somatostatin, and pancreatic polypeptide was demonstrated in granules in pancreatic endocrine fetal cells. At an early fetal stage, the endocrine cells contained either dense, round granules or pale, heteromorphous granules. With increasing age and maturation of the endocrine cells, structural differentiation of the secretory granules was found to be associated with a gradual disappearance of the polyhormonal granules. The first genuine monohormonal cell to appear in the porcine fetus was the pancreatic polypeptide cell (at 70 days gestation); it was followed by the somatostatin-producing endocrine cell. Mature insulin- and glucagon-producing cells were only demonstrated after birth. Thus, in the adult pancreatic endocrine cells, each specific endocrine cell type produced only one of the four classical hormones. The present investigation demonstrated that the endocrine cells of the fetal, but not the adult, pancreas are able to synthesize all the major islet hormones, and that these peptides are costored in the same granule. The data obtained support the concept of a common precursor stem cell for pancreatic hormone-producing cells.


Impact of insulin deficiency on glucose fluxes and muscle glucose metabolism during exercise. Exercise in the insulin-deficient diabetic state is characterized by a further increase in elevated circulating glucose and NEFA levels and by excessive counterregulatory hormone levels. The aim of this study was to distinguish the direct glucoregulatory effects of insulinopenia during exercise from the indirect effects that result from the metabolic and hormonal environment that accompanies insulin deficiency. For this purpose, dogs underwent 90 min of treadmill exercise during SRIF infusion with (SRIF + INS, n = 8) or without (SRIF - INS, n = 6) intraportal insulin replacement. Glucagon was not replaced, thus allowing assessment of the direct effect of insulinopenia at the liver independent of the potentiation of glucagon action. Glucose was infused to maintain euglycemia. Hepatic glucose production (Ra); glucose utilization (Rd); and LGlcU, LGlcE, and LGlcO were assessed with tracers ([3H]glucose, [14C]glucose) and arteriovenous differences. With exercise, insulin fell from 66 +/- 6 to 42 +/- 6 pM in the SRIF + INS group, and was undetectable in the SRIF - INS group. Plasma glucose was 6.33 +/- 0.38 and 6.26 +/- 0.30 mM at rest in the SRIF + INS and SRIF - INS groups, respectively, and was unchanged with exercise. Ra rose from 7.5 +/- 2.3 to 16.5 +/- 2.2 mumol.kg-1.min-1 and 9.1 +/- 2.0 to 31.4 +/- 3.9 mumol.kg-1.min-1 with exercise in the SRIF + INS and SRIF - INS groups, whereas Rd rose from 19.5 +/- 2.0 to 46.8 +/- 3.9 mumol.kg-1.min-1 and 15.1 +/- 1.8 to 29.9 +/- 3.3 mumol.kg-1.min-1. LGlcU rose from 36 +/- 9 to 112 +/- 25 mumol/min and 15 +/- 4 to 59 +/- 13 mumol/min and LGlcO rose from 5 +/- 2 to 61 +/- 12 mumol/min and 5 +/- 3 to 32 +/- 9 mumol/min with exercise in the SRIF+INS and SRIF-INS groups, respectively. Arterial levels and limb balances of NEFAs and glycerol were similar in the two groups. In summary, during exercise: 1) marked insulinopenia attenuates the increases in muscle glucose uptake and oxidation by approximately 50%, independent of changes in circulating metabolic substrate levels; 2) substantial increases in muscle glucose uptake and oxidation are, however, still present even in the absence of detectable insulin levels; and 3) insulinopenia facilitates the increase in Ra, independent of the potentiation of basal glucagon action. In conclusion, marked insulinopenia contributes directly to the exacerbation of glucoregulation during exercise in the diabetic state by limiting the rises in glucose uptake and metabolism and by enhancing hepatic glucose production.


Does computed tomography have a role in the evaluation of complicated acute bacterial meningitis in childhood? The authors examined the records of 30 children with bacterial meningitis to review the role of computed tomography (CT) of the brain in acute management of the disease. CT was normal for 10 patients, six of whom had clinical evidence of raised ICP. CT identified an underlying surgical abnormality in two patients with progressive focal neurological signs. One patient had unsuspected gross hydrocephalus diagnosed by CT, which required neurosurgery. This study shows that the management of bacterial meningitis is influenced by CT in only a minority of cases; for patients with clinical signs of raised ICP, it was found to be insensitive in confirming the clinical diagnosis and establishing an underlying cause. However, CT remains valuable in the management of children with progressive neurological signs for whom neurosurgical intervention may be necessary.


Duration of acid suppression in H2-antagonist nonresponders. We monitored 24-hour gastric acidity in 16 resistant duodenal ulcer patients treated with ranitidine 300 mg hora somni (9 cases) and famotidine 40 mg hora somni (7 cases) for 3 months. Data obtained in these patients were compared with those of a group of unselected duodenal ulcer patients who responded to a 4-week course of the same H2-antagonist regimens. In the time window 22.00-07.59 h there was a reduced effectiveness of ranitidine in nonresponder patients in terms of both mean pH levels (4.8 +/- 0.9 vs. 5.6 +/- 0.7, p < 0.04) and the mean duration of the antisecretory effect defined as the time spent in minutes above pH 3.0 (403 +/- 73 vs. 490 +/- 59, p < 0.02). Also, the action of famotidine was diminished in nonresponder patients in the same time interval as regards both pH values (4.1 +/- 1.6 vs. 5.7 +/- 0.6, p < 0.03) and the duration in minutes (329 +/- 163 vs. 473 +/- 45, p < 0.05). The analysis of all individual nonresponder patients shows that there was a certain variability in the duration of acid suppression: the majority of them had an adequate nocturnal acid inhibition, while in some cases of both the ranitidine and the famotidine subgroups, acid inhibition lasted only few hours or did not occur at all. At present, it is not possible to distinguish with certainty two different subsets of H2-antagonist nonresponders because of the small size of the population studied.(ABSTRACT TRUNCATED AT 250 WORDS)


Somatostatin versus secretin in the treatment of actively bleeding gastric erosions. In a double-blind, prospective, randomized trial, 63 patients with actively bleeding gastric erosions were treated with somatostatin (31 patients) or secretin (32 patients). Both drugs were administered by intravenous infusions for 48 or 72 h. The active bleeding and the effect of the therapy was endoscopically established. Somatostatin had a significantly (p < 0.05) better effect on the control of bleeding (29 vs. 23 patients), transfusion requirements (5.8 vs. 7.4 units, p < 0.01) and on the need of surgery (1 vs. 6 patients, p < 0.01). The mortality and the rebleeding rate did not differ between the two groups. The results show that somatostatin is more effective than secretin in the control of active bleeding form gastric erosions.


Gastric antisecretory effects of esaprazole in rats. The effects of esaprazole on gastric secretion (volume, pepsin and acid output) were investigated on animal models, both in vivo and in vitro. In conscious rats whose vagal activity was stimulated by pylorus ligation, esaprazole decreased volume, acid output and pepsin secretion. In anaesthetized stomach-perfused rats, esaprazole inhibited gastric acid secretion evoked by both vagus nerve stimulation or bethanechol infusion. By contrast, on isolated guinea-pig gastric fundus, esaprazole failed to counteract the acid output stimulated by histamine, bethanechol or pentagastrin. In addition to this, phasic contractions evoked by acetylcholine on isolated guinea-pig ileum were antagonized by esaprazole only at high concentrations. The present results suggest that the inhibitory actions of esaprazole on secretory parameters involve the cholinergic parasympathetic pathway, probably through both direct and indirect mechanisms.


The role of acid regulation in the treatment of NSAID-induced mucosal damage. Gastric acid probably exacerbates mucosal injury caused by non-steroidal anti-inflammatory drugs (NSAIDs) in two ways: first, by increasing absorption of NSAIDs, which are weak acids and predominantly in their undissociated form at low pH--this is probably mainly relevant for salicylates; then, by a 'second wave' of injury that leads to deeper erosions, as gastric acid accesses the partially denuded mucosa. Regulation of gastric acid secretion by acid-inhibitory drugs has been shown to decrease acute NSAID-induced injury to varying extents, depending on the drug used and the method of assessing mucosal damage. Healing of chronic NSAID-induced ulcers is slow if NSAID therapy is continued, but is facilitated by treatment with H2-receptor antagonists or prostaglandins. One study of the acid pump inhibitor omeprazole has shown a high rate of healing, even though NSAID therapy was continued.


Medical therapy of patients with reflux oesophagitis poorly responsive to H2-receptor antagonist therapy. There is substantial clinical experience of omeprazole treatment in patients with reflux oesophagitis, who have an incomplete or failed response to profound and prolonged acid-inhibitory therapy with H2-receptor antagonists. In The Netherlands, most patients with reflux oesophagitis poorly responsive to high-dose H2-receptor antagonists were healed within 3 months of treatment with omeprazole, 40 mg once daily. Only a few patients (less than 10%) with complicated reflux oesophagitis needed a longer duration of treatment or a higher dose of omeprazole to achieve complete endoscopic healing. Follow-up for up to 6 years has shown that most of these patients could be maintained successfully on omeprazole, 20 mg daily. However, about one third of the patients relapsed after healing when the maintenance dose was introduced. Evaluation of these patients who relapsed has shown that they require a higher level of acid-secretory inhibition; a maintenance dose of omeprazole, 40 mg once daily, rehealed the oesophagitis within 3 months. Only a few patients had a second relapse, and these patients were rehealed by an increase of the omeprazole dose to 60 mg daily. Oesophageal pH monitoring in these patients has shown that there is continued pathological oesophageal acid exposure, predominantly during the night, suggesting that the duration of major action of omeprazole was insufficient for production of adequate elevation of intragastric pH during the night. Successful control of reflux disease in these patients was achieved by increasing omeprazole therapy to a regime and dosage that achieved elevation of intragastric pH above 4 throughout the 24-hour period.


Acid suppression in the long-term treatment of peptic stricture and Barrett's oesophagus. Peptic stricture and Barrett's oesophagus are not only the major, but also the most common, complications of gastro-oesophageal reflux disease. The clinical problems that these manifestations present are highly significant, and in patients with peptic stricture the resultant dysphagia can be a major disability that causes nutritional problems. Dilation of a stricture exposes the patient to a small, but significant, risk of oesophageal perforation. Barrett's oesophagus per se rarely causes morbidity, but carries a significant risk of developing oesophageal carcinoma, with its attendant morbidity and mortality. Successful anti-reflux surgery for peptic stricture and Barrett's oesophagus effectively abolishes pathological oesophageal acid exposure and provides the best indicator of the potential benefits that may be obtained from treatment with acid-inhibitory drugs. The reported experience clearly indicates that successful anti-reflux surgery results in resolution of peptic stricture following initial dilation, concomitant with persistent control of oesophageal acid exposure. In patients with Barrett's oesophagus, healing of oesophagitis is well documented after successful surgery, but it is unclear whether the Barrett's epithelium progresses or regresses significantly in all but a minority of patients. It is now established that acid pump inhibition can reduce pathological oesophageal acid exposure as effectively as successful anti-reflux surgery. In a minority of patients, however, omeprazole, 40 or 60 mg daily, divided into two doses, is necessary to achieve this effect. This is particularly true for patients with the more severe forms of disease, in whom peptic stricture and Barrett's oesophagus are most prevalent. Results indicate that peptic stricture can resolve during effective gastric acid inhibition with omeprazole, and results from controlled trials on the management of these patients with omeprazole are awaited. Similarly, there are reports of regression of Barrett's oesophagus during omeprazole therapy, but the completeness and predictability of any such effect have not yet been adequately evaluated. There is sufficient experience from long-term omeprazole treatment of gastro-oesophageal reflux disease to indicate that maintenance of a satisfactory response of peptic stricture or Barrett's oesophagus depends upon continued effective gastric acid inhibition.


Preferential location of somatostatin receptors in germinal centers of human gut lymphoid tissue. Somatostatin receptors were evaluated in four human gut-associated lymphoid tissues (palatine tonsils, ileal Peyer patches, vermiform appendix, and colonic solitary lymphatic follicles) using receptor autoradiography on tissue sections incubated with 125I[Tyr3]octreotide. All four tissues were somatostatin-receptor positive; the receptors were preferentially located in the germinal centers, with the luminal part of the center more strongly labeled than the basal part. The corona of the follicles and the primary follicles without germinal centers did not display somatostatin receptors. The receptors were of high affinity (Kd = 1.3 +/- 0.6 nmol/L) and specific for somatostatin. Displacement by nanomolar concentrations of somatostatin 14, somatostatin 28, and octreotide was observed, as was guanosine triphosphate dependency. The gastrointestinal mucosa and the plexus submucosus and myentericus also contained somatostatin receptors. These data strongly suggest that the germinal centers of the gut-associated lymphoid tissue are a site of action of somatostatin. It possibly mediates antiproliferative effects and inhibits immunoglobulin synthesis in the activated lymphoid cells. The human gut represents a multifaceted target for somatostatin action, in which at least three different tissues (mucosa, nerve plexus, and lymphoid tissue) are involved.


Intestinal fat does not inhibit gastric function through a hormonal somatostatin mechanism in dogs. In awake dogs with chronic gastric, duodenal, and jejunal fistulas, F(ab)1 fragments of somatostatin monoclonal antibody (mAb S607) were administered intravenously (IV) to test the hypothesis that intraintestinal lipid inhibits peptone-stimulated gastric acid secretion and emptying by a hormonal somatostatin mechanism. Plasma somatostatin was increased significantly by duodenal and jejunal perfusion with 20% lipid. Somatostatin administered IV caused dose-dependent inhibition of meal-stimulated gastric acid secretion and gastric emptying similar to that seen after intestinal perfusion with lipid. Administration of mAb S607 F(ab)1 fragments significantly reversed somatostatin (400 pmol.kg-1.h-1, IV)-induced inhibition of peptone-stimulated acid output and gastric emptying. Acid output inhibited by intraduodenal lipid was reversed partially after F(ab)1 administration, but the inhibitory effect of intrajejunal lipid was not altered. Inhibition of acid secretion by IV somatostatin and by intraintestinal fat was not caused by a decrease in circulating gastrin concentrations. Gastric emptying delayed by intraintestinal lipid was unaffected by antibody administration. Somatostatin does not appear to be a major hormonal mediator of intestinal fat-induced inhibition of gastric acid secretion or delayed gastric emptying in dogs.


Effect of chymotrypsin on rat blood pressure. 1. Chymotrypsin (Cht) administration (14 mg/kg, i.v.) to rats always caused hypertension; hypotension preceded this effect in 64% of the observations (n = 11). 2. A 68% reduction of circulating kininogen but not of angiotensinogen was observed after Cht administration. 3. Cht effects were not affected by captopril, [Sar1-Leu8]-angiotensin II and alpha-adrenoceptor antagonists. In 70% of the observations (n = 10) hypotension was abolished by a mixture of histamine H1- and H2-antagonists. Therefore histamine release may explain hypotension. 4. Cht released in vitro from rat plasma, a substance producing hypertension in the rat and contraction of the guinea-pig ileum. Both effects were antagonized by [Sar1-Leu8]-angiotensin II. 5. In spite of this angiotensin release in vitro, the hypertensive component of the in vivo response to Cht seems to be due to some other substance.


Opposite influences of dopaminergic receptor subtypes on penile erection. 1. Mixed D-1/D-2 dopamine agonist apomorphine induced a penile erection (PE) in rats in a biphasic manner. 2. The response was decreased with increasing doses of the drug. 3. The maximum effect was obtained by 0.1 mg/kg of apomorphine. 4. In animals pretreated with D-1 antagonist SCH 23390, high doses of apomorphine showed higher PE response, while D-2 antagonist sulpiride pretreatment decreased the response of the low doses of the drug. 5. The inhibitory effect of sulpiride was dose-dependent. 6. The D-2 agonists bromocriptine or quinpirole induced a dose-dependent PE. 7. The effects of both drugs were decreased by sulpiride or SKF 38393 pretreatment. 8. Cholinergic drugs physostigmine and neostigmine did not induce PE, but antimuscarinic agent atropine decreased the effects of apomorphine, bromocriptine or quinpirole. 9. It is concluded that D-2 dopamine receptor stimulation may induce PE, while D-1 activation elicit an opposite effect. 10. However, cholinergic stimulation is not able to induce PE, cholinergic inhibition may decrease the PE induced by dopaminergic agents.


Mechanism of ebrotidine protection against gastric mucosal injury induced by ethanol. 1. The gastroprotective properties of a new H2-receptor antagonist, ebrotidine, against ethanol-induced mucosal injury was investigated. 2. Groups of rats, with and without indomethacin pretreatment, received intragastrically either a dose of ebrotidine or vehicle only, followed by ethanol given at various intervals up to 4 hr. The gastric mucosa, 30 min after the ethanol challenge, was then subjected to macroscopic and histologic examination, and physicochemical measurements. 3. Ebrotidine at doses of 50 mg and higher per kg body wt effectively prevented the alcohol-induced mucosal injury, even in the presence of indomethacin. The protective effect was demonstrable already at 30 min, reached maximum at 1 hr, and persisted up to 3 hr. 4. Physicochemical analyses established that ebrotidine elicited 30% increase in mucus gel dimension, caused 19-20% increase in glycolipids and phospholipids, and evoked 21% increase in sulfomucin and 18% in sialomucins. As a consequence, the mucus gel viscosity increased by 1.4-fold, H+ retardation capacity by 16%, and hydrophobicity by 65%. 5. The results demonstrate that ebrotidine is a unique H2-antagonist endowed with a remarkable mucosal strengthening capability.


Biphasic effect of tetraethylammonium on canine purkinje fibre action potential configuration. 1. Using conventional microelectrode techniques a biphasic effect of tetraethylammonium (5 mmol/l) on the configuration of action potentials recorded from isolated canine Purkinje fibres: action potentials were first shortened (early effect) and then lengthened (late effect) by tetraethylammonium. 2. The early effect of tetraethylammonium also included lengthening of phase 1 duration and elevation of the plateau amplitude. These early effects reached steady-state within the first 3 min of superfusion and were readily reversed within 3 min of initiating washout of the drug. 3. The late effect (gradual lengthening of repolarisation during phase 3) failed to reach steady-state within the initial 60 min of superfusion and was not reversible. 4. The early effects of tetraethylammonium were more marked at slow driving rates and were not affected by blockade of alpha- and beta-adrenoceptors using 1 mumol/l phentolamine and 1 mumol/l propranolol. 5. The early effects of tetraethylammonium were mimicked by 4-aminopyridine (0.5 mmol/l), and in the presence of 4-aminopyridine tetraethylammonium failed to induce further changes in action potential morphology. 6. The early effects of tetraethylammonium may be due to inhibition of the transient outward current. 7. The rapid onset and reversibility of these early effects suggest that tetraethylammonium may act from outside the cell membrane.


Analgesic effect of benzodiazepines and flumazenil. 1. In the present work the analgesic effect of benzodiazepines (BZD) and flumazenil (FLU) using the writhing test in mice was studied. 2. Intracerebroventricular administration of BZD exhibited a dose-dependent antinociceptive effect when compared to control value. 3. Intracerebroventricular administration of FLU induced a dose-dependent antinociceptive action that was not antagonized by naloxone (NX). 4. BZD administered as subcutaneous pellets produced an antinociceptive action in the writhing test, when compared to control mice, only at relative high doses and was partially antagonized by naloxone. 5. These findings could be explained assuming that NX and/or FLU have partial agonist properties in a common receptor which mediates the antinociceptive action. 6. The antinociceptive action of BZD could be related to an increased release of adenosine, which by itself has analgesic effects.


Modulation of noradrenergic transmission in the rat isolated portal vein: role of prejunctional alpha 2-adrenoceptors and beta-adrenoceptors. 1. The effect of several adrenoceptor agonists and antagonists on the spontaneous and stimulus-evoked release of [3H]noradrenaline was studied in rat isolated portal vein. 2. Yohimbine (10(-6)M) increased the stimulus-evoked [3H]noradrenaline efflux. Adrenaline alone (3 x 10(-6)M) was without effect, while it increased the resting efflux when added together with yohimbine. 3. Propranolol alone was without effect on the release of [3H]noradrenaline. When added (2 x 10(-6)M) at the same time as yohimbine, it reduced the stimulation-induced 3H efflux. When added before adrenaline and yohimbine, propranolol (10(-5)M) reduced both spontaneous and stimulus-evoked release of [3H]noradrenaline. 4. The effect of several beta-blocking drugs was measured on the enhancing effect of yohimbine on the stimulation-evoked 3H efflux. The beta 1-adrenoceptor blocking drugs: atenolol (5 x 10(-6) and 10(-5) M), metoprolol (5 x 10(-6) and 10(-5) M), like the more selective bisoprolol (2 x 10(-6) and 4 x 10(-6) M) inhibited yohimbine activity. Likewise, propranolol (2 x 10(-6) and 5 x 10(-6)M) and the beta 2-adrenoceptor blocker ICI 118551 exhibited an antagonistic effect. 5. These results indicate the possibility for noradrenaline to activate presynaptic beta-adrenoceptors in rat portal vein. They show an interaction between the presynpatic alpha 2- and beta-adrenoceptor mediated systems in the release of noradrenaline. They suggest the presence and the activity of facilitatory beta 1-adrenoceptors.


The occurrence and in vitro effects of molecules potentially active in the control of growth in the marine mussel Mytilus edulis L. A molecular with a molecular weight, estimated by gel filtration, of approximately 22 kDa and immunoreactive to anti-human hypophysial growth hormone (hGH) has been identified by radioimmunoassay in the digestive gland and hemolymph of the mussel Mytilus edulis L. The dilution curve of this molecule was parallel to that of hGH, suggesting that the antigenic site of the Mytilus molecule is similar to that of hGH. Immunoreactive fractions resulting from gel filtration failed to stimulate protein synthesis in dispersed mantle-edge cells in vitro. No hGH-immunoreactive material was detected in the cerebral ganglia. It is thus clear that a small protein-synthesis-stimulating factor (PSSF), identified in the cerebral ganglia and hemolymph by its action in vitro on dispersed mantle-edge cells, is not analogous to the Mytilus hGH-immunoreactive molecule. Likewise, a somatostatin-immunoreactive molecule present in the hemolymph of Mytilus did not coelute with PSSF. Evidence is presented that PSSF is a hydrophilic peptide that stimulates DNA, RNA, and protein synthesis and that is not tissue specific. These characteristics suggest that PSSF is a growth hormone.


Neurohormonal control of growth and carbohydrate metabolism by the light green cells in Lymnaea stagnalis. The neuroendocrine light green cells (LGCs), 4 clusters of together approximately 150 giant neurons in the cerebral ganglia of the freshwater gastropod, Lymnaea stagnalis, have been suggested to be involved in the control of growth. The present study examines in greater detail this role and possible actions on energy metabolism. Growth indices (total body and organ wet and dry weights, as well as protein and DNA contents of the organs) and metabolic indices (tissue lipid, polysaccharide and glucose levels) were compared in LGC extirpated/reimplanted with control groups. LGC extirpation in rapidly growing juvenile snails immediately arrested growth, which was restored by reimplantation of cerebral ganglia with LGCs but not by cerebral ganglia without LGCs, indicating their neuroendocrine control of growth. The LGCs stimulate a pattern of organ growth, which is in proportion to the growth of the whole body except for the shell, which shows a disproportionally faster growth due to calcium deposition over the whole surface. The data on protein and DNA in the organs strongly suggest that the LGCs induce growth by stimulating cell multiplication. The LGCs maintain low tissue glycogen reserves and hemolymph concentrations of both glycogen and glucose. The secretions of these cells stimulate the uptake of glucose by the growing tissues with no apparent effects on lipid metabolism.


An immunocytochemical study of the endocrine pancreas in three genera of lacertids. The comparative morphology of the endocrine pancreas was studied in 11 species of lacertids. Four major cell types were identified immunocytochemically in the endocrine pancreas: glucagon-immunoreactive A-cells, insulin-immunoreactive B-cells, somatostatin-(SRIF)-immunoreactive D-cells, and pancreatic polypeptide(PP)-immunoreactive F-cells. Different distributions of the four cell types were seen in the endocrine tissue within the exocrine parenchyma. F-cells were rare or absent in the splenic lobe and abundant in the duodenal lobe, in which they were usually widespread in the exocrine parenchyma and rarer in the islets. The other three cell types were always present in the islets. The central core consisted of B- and A-cells, with B-cells predominating. The peripheral mantle was formed by A-cells and less abundant D-cells. Rare D-cells were also found in the central core. D- and F-cells showed projections often closely associated with capillaries. The observed arrangements in islets and isolated cells may represent an endocrine network that, in addition to systemic actions, may regulate exocrine function in a paracrine fashion.


Dietary intake and gene variation influence the response of plasma lipids to dietary intervention. We have examined whether variation at the apolipoprotein (apo) B, apo E, apo AII, and apo AI-CIII-AIV genes affected the relationship between dietary intake and serum lipid traits in individuals who had participated in dietary intervention from a basal high fat diet to a low fat diet followed by a return to their natural diet, the switchback. On both the basal and switchback diets where the variance of dietary intake was great, there was a significant correlation between P/S ratio and serum total, low-density lipoprotein (LDL) cholesterol, and apo AI levels. In addition dietary cholesterol (dchol) levels correlated significantly with serum apo AI levels on the basal diet. Comparing the difference between basal and intervention (delta 1) and between switchback and intervention diets (delta 2), changes in dchol and P/S ratio correlated significantly with changes in serum total, high-density lipoprotein (HDL) and LDL cholesterol, and apo B levels. There was a significant correlation between monounsaturated fatty acid (MUFA) and apo AI levels during both changes. Furthermore we have examined whether the relationship between variables was homogeneous among genotypes of candidate gene polymorphisms. A heterogeneous effect (P less than 0.01) was seen among genotypes of the PvuII-AIV restriction fragment length polymorphism (RFLP) on the correlation of serum LDL cholesterol levels and dietary MUFA during both dietary changes (delta 1 and delta 2). A heterogeneous effect among genotypes of the apo B XbaI RFLP on the correlation between dchol versus total and LDL cholesterol during the change delta 1, but not delta 2, was observed. Thus our results show that both dietary components and genetic variation affect the response of serum lipid, lipoprotein, and apolipoprotein levels to dietary change.


Sexual development genes of Neurospora crassa. The filamentous fungus Neurospora crassa undergoes a complex program of sexual development to form a fruiting body composed of several kinds of specialized tissue. Subtractive hybridization was used to isolate genes that are expressed preferentially during this sexual phase. Many such sexual development (sdv) genes were identified in a cosmid library of Neurospora genomic DNA. Fourteen of the sdv genes were subcloned, and their expression in mutant strains and under crossing and vegetative growth conditions was examined. All of the regulated transcripts were less abundant (and in many cases not detectable) in strains grown under vegetative (high nitrogen) conditions, suggesting that nitrogen starvation is required for their synthesis. The expression of most of the sdv genes also required a functional A mating type product, even under crossing growth conditions, suggesting that this product functions as a master control in sexual development. To determine if the products of the sdv genes play essential roles in the sexual cycle, a reverse-genetic approach (based on RIP (repeat-induced point mutation)-mediated gene disruptions) was used to create mutations in the genes. A mutant strain (asd-1) with a recessive crossing defect (apparently caused by the RIP process) was isolated; in this strain, early development is normal and may asci are formed, but ascospores are never delineated. A second recessive mutant strain (asd-2) was apparently created by ectopic integration of the transforming DNA into a gene required for the sexual process; in this strain the sexual process was blocked at an early stage, and the ascogeneous tissue underwent little development.


The Rhizobium leguminosarum biovar phaseoli glnT gene, encoding glutamine synthetase III. Plasmid pGE203 contains the Rhizobium leguminosarum biovar phaseoli glnT locus. Glutamine synthetase III (GSIII) was purified from a glutamine auxotrophic strain of Klebsiella pneumoniae carrying this plasmid. Sequencing of a 2.4-kb fragment containing the glnT locus reveals an open reading frame of 435 amino acids (aa), whose first eight aa are identical to those determined from pure GSIII by direct aa sequencing, thus confirming that glnT indeed codes for GSIII activity. The comparison of the GSIII aa sequence with the reported sequence of GSs from other organisms shows a significant degree of homology. Since the three-dimensional structure of GS from Salmonella typhimurium is known, a three-dimensional model of GSIII was built by homology.


Heteroplasmy of short tandem repeats in mitochondrial DNA of Atlantic cod, Gadus morhua. The mitochondrial DNA of the Atlantic cod (Gadus morhua) contains a tandem array of 40-bp repeats in the D-loop region of the molecule. Variation among molecules in the copy number of these repeats results in mtDNA length variation and heteroplasmy (the presence of more than one form of mtDNA in an individual). In a sample of fish collected from different localities around Iceland and off George's Bank, each individual was heteroplasmic for two or more mtDNAs ranging in repeat copy number from two (common) to six (rare). An earlier report on mtDNA heteroplasmy in sturgeon (Acipenser transmontanus) presented a competitive displacement model for length mutations in mtDNAs containing tandem arrays and the cod data deviate from this model. Depending on the nature of putative secondary structures and the location of D-loop strand termination, additional mechanisms of length mutation may be needed to explain the range of mtDNA length variants maintained in these populations. The balance between genetic drift and mutation in maintaining this length polymorphism is estimated through a hierarchical analysis of diversity of mtDNA length variation in the Iceland samples. Eighty percent of the diversity lies within individuals, 8% among individuals and 12% among localities. An estimate of theta = 2N(eo) mu greater than 1 indicates that this system is characterized by a high mutation rate and is governed primarily by deterministic dynamics. The sequences of repeat arrays from fish collected in Norway, Iceland and George's Bank show no nucleotide variation suggesting that there is very little substructuring to the North Atlantic cod population.


Sequences of the genes encoding the minor tip components of Pap-3 pili of Escherichia coli. We report the sequence of the papE, papF and papG genes from the O75:K5 uropathogenic P pili variant, Pap-3. Comparison of the deduced amino acid sequences with those of other P pili variants reveals regions of complete homology, as well as regions of variation. Analysis of the variations in the hydrophilic domains of these proteins will help elucidate the residues which determine binding specificity.


Three year follow up of patients with gastrooesophageal reflux disease. Data on the natural course of gastrooesophageal reflux disease are sparse. One hundred and sixty six patients with typical reflux symptoms (heartburn and/or acid regurgitation) and pathologic pH monitoring (reflux time > 8.2% upright and/or > 3.0% supine) were studied. The patients were followed up by questionnaire and interview for a mean of 41 (seven to 86) months after diagnosis of reflux disease. Ten patients had died of diseases not reflux related. In 117 (75%) of the remaining 156 patients data on the course of gastrooesophageal reflux disease could be obtained. In 12 patients anti reflux surgery had been performed. Forty one (39%) of the remaining 105 patients have stopped taking medical therapy, in 13 of these patients symptoms had completely disappeared. Sixty four patients continued on medication (40 on demand, 24 regularly). When asked how their symptoms would be if they completely stopped medication, 71 patients considered their symptoms to be equal or worse and 21 patients to be improved as compared with the initial investigation. Patients with persisting symptoms at follow up had significantly more supine reflux (p < 0.05) at the initial pH monitoring as compared with patients with improved symptoms. The presence and grade of oesophageal erosions at initial endoscopy, duration of symptoms, age, sex, and smoking habits had no influence on the course of gastrooesophageal reflux disease. In conclusion, reflux symptoms disappear only in a minority of patients with proven gastrooesophageal reflux disease. More than half of all patients continue medication, either on demand or regularly. Severe supine reflux is an unfavourable prognostic factor.


Intestinal hypersecretion of the refed starved rat: a model for alimentary diarrhoea. Fluid transport was gravimetrically measured in vivo in the duodenum, jejunum, and ileum of anaesthetised fed, 72 hour starved and 72 hour starved rats refed for up to five days after starvation. Basal unstimulated fluid transport was monitored by instilling 0.9% NaCl into the lumen and measuring the gain or loss in weight of the closed intestinal loop. Fluid was absorbed in all the areas of the intestine in the fed rats. Increasing basal fluid absorption was observed in the duodenum over the three days of starvation but in the jejunum there was no significant change. In the ileum, the pattern was very different, on day 1 the fluid was absorbed but on days 2 and 3 there was an increasing secretion of fluid. Refeeding the rats with their normal diet restored the basal absorption of fluid in the duodenum within 24 hours, had no effect in the jejunum but in the case of the ileum the hypersecretion of fluid observed in the day 3 starved rat was maintained on day 1 of refeeding, increased further on day 2, decreased on day 3 but returned to absorption on day 4. The normal absorption was restored to the ileum on day 5 of refeeding. Fluid secretion was induced in all the rat groups by bethanechol (ip 60 micrograms/kg bw) a stable cholinergic agonist, PGE2 (ip 10 micrograms/kg (bw) and E coli STa (luminally instilled, 500 ng/ml) a secretory enterotoxin. All the secretagogues gave enhanced secretion compared with the fed by day 2 of starvation which increased considerably on day 3. Refeeding returned their secretion back to the fed level in the duodenum within 24 hours, in the jejunum within 48 hours but in the ileum their induced secretion on day 2 of refeeding was greater than that of the day 2 of refeeding was greater than that of day 3 starved and took until day 4 to return to the fed levels for behanechol and PGE2 and until day 5 for E. coli STa. This behaviour of rat small intestine showing even greater hypersecretion in the refed state than the starved mimics the human condition of alimentary induced diarrhoea where incautious feeding of starved humans induces severe, often lethal diarrhoea. The refed starved rat appears to be a possible model for this condition.


Proliferative activity of human uterine leiomyoma cells as measured by automatic image analysis. Proliferative activity of uterine leiomyomas from premenopausal (n = 44) and postmenopausal (n = 12) women was investigated by automatic image analysis on frozen tissue sections using immunohistochemistry with anti-proliferating cell nuclear antigen antibody. The quantitative proliferation index (QPI) in premenopausal leiomyoma cells was significantly (p < 0.025) higher than that in leiomyomas in postmenopausal women. Leiomyomas proliferated most actively during the secretory phase. After the climacterium, leiomyomas showed no proliferative activity in the absence of hormone supply, while combined substitution with estrogen and progestagen considerably increased QPI.


[Neurotransmission and nitric oxide (NO)]. The history of how we reached the goal of determining the mechanism of vasodilatation caused by non-adrenergic, non-cholinergic nerve stimulation in cerebral arteries was traced. We concluded from this project that electrical and chemical (by nicotine) stimulations evoke an increased influx of Ca2+ into nerve terminals and activate nitric oxide (NO) synthase, resulting in the synthesis and release of NO that stimulates the guanylate cyclase in smooth muscle, thereby causing the accumulation of cyclic GMP and eliciting muscle relaxation. Reviewed also are the neurally-induced inhibitory responses of extracranial arteries, intestines, etc. with respect to NO.


Molecular pathology of inherited erythrocyte membrane disorders: hereditary spherocytosis and elliptocytosis. Hereditary spherocytosis and elliptocytosis are common genetic defects of the red blood cell membrane skeleton. In recent years rapid advances have been made in the knowledge of the protein structure and assembly of the cytoskeleton. Thanks to the wide use of protein analysis methods several alterations have been discovered in functionally important domains of the different cytoskeletal proteins in these diseases. The cloning of cDNA for the majority of the cytoskeletal proteins allows us to begin elucidating some of these defects at the DNA level. This paper will review the effects of recent advances upon: cytoskeleton structure and assembly; molecular pathology of spherocytosis, elliptocytosis and pyropoikilocytosis.


[The role of beta-adrenoceptor subtypes in cardiac contractility]. Since the existence of beta 3-adrenoceptors in various organs has been established, it is necessary to re-evaluate the subtypes of beta-adrenoceptors in cardiac muscle. We have demonstrated the possible existence of three subtypes of beta-adrenoceptors: beta 2-adrenoceptors, high-affinity beta 1-adrenoceptors (the so-called beta 1-adrenoceptors) and the low-affinity beta 1-adrenoceptors (akin to beta 3-adrenoceptors) in canine cardiac muscle, which are coupled with increases in myocardial cyclic AMP content and positive inotropic effects. Cyclic AMP generated by the activation of the high-affinity beta 1-adrenoceptors seems to be coupled with the positive inotropic effect much more effectively than via beta 2- or low-affinity beta 1-adrenoceptors. Stimulation of beta 2-adrenoceptors or the low affinity beta 1-adrenoceptor is causally related to the development of tolerance and to the adverse effects of nonselective beta-full agonists. It is conceivable that with denopamine, unlike with isoproterenol, tolerance can hardly develop, and there are no adverse effects resulting from its partial agonistic property and its selectivity for the high-affinity beta 1-adrenoceptors. The selective stimulation of the high-affinity beta 1-adrenoceptors would be beneficial for the management of mild congestive heart failure. In contrast, stimulation of the low-affinity beta 1-adrenoceptors by endogenous catecholamines or nonselective beta-agonists will contribute to deteriorating hemodynamic, symptomatic and prognostic consequences in patients with congestive heart failure.


A case of Langerhans histiocytosis with HIV-like immunodeficiency. A case of histiocytosis X (Langerhans type) associated with bullous pulmonary emphysema and acquired immune deficiency, regarding CD4 positive cells, is described. Previous history was remarkable for skin lesions which first appeared in 1981 and progressively worsened, diabetes insipidus diagnosed in 1986, and bullous pulmonary emphysema detected in 1988. Biopsy results of skin lesions were consistent with histiocytosis X. Thyroid gland involvement was found by means of cytological examination. The search for HIV infection (also performed by means of immunoblotting and PCR) was negative. To our knowledge the immunodeficiency detected in histiocytosis X affects the T suppressor lymphocyte subset, so we thought this peculiar case was worth describing.


[Effects of FRG-8813, a new type histamine H2-receptor antagonist, on various experimental gastric and duodenal lesions in rats]. We examined the anti-ulcer effects of FRG-8813, a new type histamine H2-receptor antagonist, on various experimental gastric and duodenal lesions in rats. FRG-8813, administered orally, inhibited the formation of lesions dose-dependently in experimental models with the exception of the Shay ulcer model. The anti-ulcer potency of FRG-8813 was 4 approximately 10 times greater than that of cimetidine when the ED50 values of both compounds were compared. Famotidine and cimetidine inhibited lesion formation at higher doses than the anti-secretory doses. The anti-ulcer action of FRG-8813, however, appeared at even lower doses than those of anti-secretory action. These results suggest that FRG-8813 is able to prevent lesion formation with anti-secretory action plus other mechanisms unlike typical histamine H2-receptor antagonists.


[Effects of FRG-8813, a new-type histamine H2-receptor antagonist, on the healing of gastric and duodenal ulcer in rats and spontaneously ulcerative mice]. We examined the anti-ulcer effects of FRG-8813, a new-type histamine H2-receptor antagonist, in chronic ulcer models of rats and mice (W/WV). FRG-8813, given orally twice a day for 7 days, accelerated the healing of gastric or duodenal ulcer induced by acetic acid injection or application at the non-antisecretory doses (0.3 approximately 3 mg/kg). Administration of FRG-8813 to rats with ulcers increased the amounts of mucus in the gastric mucosa. These actions of FRG-8813 were more potent than those of famotidine or cimetidine. In W/WV mice, several ulcers spontaneously developed on gastric mucosa during the 8 weeks after the birth. The ulcers were aggravated by several unknown factors after the ulcer generation in W/WV mice. The aggravation of ulcers was inhibited by the 4-week administration of FRG-8813 with diet at the dose of 1 or 10 mg/kg/day, but was not inhibited by cimetidine at the dose of 100 mg/kg/day. From these results, we suggest that FRG-8813 is able to accelerate the healing of ulcers by antisecretory plus increasing actions on the integrity of the gastric mucosal defense mechanisms; therefore FRG-8813 is expected to be a useful drug for the treatment of gastric or duodenal ulcers in humans.


[Effects of beta blockers on lipoprotein metabolism]. With respect to prevention of its most common complication--mortality from coronary heart disease--treatment of hypertension had disappointed. It is possible that this is due to negative effects of antihypertensives on lipid metabolism. The effects of beta blockers on lipid metabolism can be differentiated principally, in accordance with the classification of beta blockers into those with and those without intrinsic sympathomimetic activity (ISA), as also selectivity and non-selectivity. Thus, non-selective beta blockers with no ISA usually lead to an increase in triglycerides of 25% to 30%, and a decrease in HDL cholesterol of about 15%. On average, beta-1 selective blockers result in a smaller increase in triglycerides. Beta blockers with ISA, in contrast, are largely neutral vis-à-vis lipid metabolism. In the individual case, in particular in the presence of hyperlipoproteinemia, the effects cannot be reliably predicted. Lipoprotein concentrations should be monitored during treatment with beta blockers. If necessary, a change in the agent employed is recommended. In the case of prevention of a second myocardial infarction, for which various studies have unequivocally shown a reduction in mortality associated with treatment with beta blockers with no ISA, these side effects will, however, be accepted--with the exception of extreme changes--for a limited period of time.


New mechanisms of hormone secretion: MDR-like gene products as extrusion pumps for hormones? P-glycoprotein, the product of the multidrug resistance (MDR1) gene, is an ATP-driven transmembrane pump that increases the resistance of cells by actively exporting toxic chemicals. In addition to transporting anticancer drugs, P-glycoprotein has been reported to extrude a variety of lipophilic drugs, such as calcium channel blockers, phenothiazines, cyclosporines etc. Interestingly, recent experiments suggest that steroid hormones may be physiologic substrates for P-glycoprotein. In addition, there exists a family of transporter genes with high structural homology to P-glycoprotein, the so-called ABC (ATP-binding casette) family. Although the physiological ligands for most of these transporters are unknown, there is increasing evidence that peptides may be transported by some of these proteins. Thus, the a-factor, a farnesylated pheromone with 13 amino acids, is exported from yeast cells by the product of the STE6 gene, a transporter protein with high homology to P-glycoprotein. Recently, we have cloned a novel member of the ABC-transporter gene family from neuroblastoma x glioma hybrid (NG-108-15) cells. This putative transporter gene ("NG-TRA") is expressed in the adrenal gland, kidney and in the brain. High amounts of NG-TRA mRNA are found in a variety of human brain tumors. Whether NG-TRA and/or other MDR-related transporters are involved in the transport of steroids, peptide hormones or growth factors remains to be established. If so, the cellular export of hormones by active pumps may represent a new mechanism of hormone secretion.


Molecular analysis of the androgen receptor gene in 52 patients with complete or partial androgen insensitivity syndrome: a collaborative study. In patients with androgen insensitivity syndrome (AIS), RFLP study of the androgen receptor gene made it possible to analyze whether deletions or mutations could be responsible for abnormalities in androgen responsiveness. We studied RFLPs of DNA from 25 46,XY patients with partial AIS (PAIS), defined as a concentration of androgen receptor in genital-skin fibroblasts less than 340 fmol/mg DNA, and DNA from 27 46,XY patients with complete AIS (CAIS) with no detectable androgen receptor site. DNA samples were digested with BamHI, EcoRI, HindIII and TaqI restriction enzymes and hybridized with three cDNA probes covering the three domains of the androgen receptor. When we had the maternal and an unaffected brother's DNA, we analyzed the two androgen receptor gene polymorphisms described, the HindIII and the exon 1 CAG repeat polymorphisms, in order to distinguish the two maternal X chromosomes, and to detect carriers of AIS. We did not find any large deletion among the 52 patients. We observed a heterozygous mother in 3 of 14 families studied with the HindIII polymorphism, and in 12 of 25 families using the exon 1 CAG repeat polymorphism. This study suggests that in AIS, abnormalities in androgen receptor response could be related to point mutations or microdeletions rather than to gross structural alterations of the androgen receptor gene. Furthermore, unless the point mutation has been described, exon 1 and HindIII polymorphism studies would enable the identification of carriers in 50% of families, and the prenatal diagnosis of AIS.


Serum thyrotropin response to combined arginine and thyrotropin-releasing hormone administration provides evidence for an altered somatostatinergic tone in acromegaly. The aim of this study was to evaluate plasma thyrotropin (TSH), prolactin (PRL) and growth hormone (GH) responses to the TSH-releasing hormone (TRH) test and to a combined arginine-TRH test (ATT-TRH) in 10 normal subjects and in 15 acromegalic patients. In controls, TSH responsiveness to TRH was enhanced by ATT (p less than 0.001). When considering the 15 acromegalic patients as a whole, no significant difference in TSH responses was detected during the two tests. However, patients without suppression of plasma GH levels after oral glucose load showed an increased TSH responsiveness to the ATT-TRH test if compared to TRH alone (p less than 0.025), while patients with partial suppression of plasma GH levels after glucose ingestion showed a decreased TSH responsiveness to ATT-TRH (p less than 0.05). No difference was recorded in PRL and GH responses, evaluated as area under the curve, during TRH or ATT-TRH tests in controls and in acromegalics. In conclusion, (1) normal subjects have an enhanced TSH response to the ATT-TRH test and (2) acromegalic patients without suppression of GH levels after oral glucose load show a TSH responsiveness to the ATT-TRH test similar to that of controls, while acromegalics with partial GH suppression after oral glucose load have a decreased TSH responsiveness to the ATT-TRH test. These data suggest that acromegaly is a heterogeneous disease as far as the somatostatinergic tone is concerned.


Monitoring of neurotransmitter amino acids by means of an indwelling cisterna magna catheter: a comparison of two rodent models of fulminant liver failure. Alterations of brain and cerebrospinal fluid amino acids have consistently been described in human and experimental fulminant liver failure. To evaluate the significance of such changes in the pathogenesis of hepatic encephalopathy in fulminant liver failure, brain and cerebrospinal fluid amino acids (glutamate, aspartate, GABA, glycine, taurine) were measured at various stages during the development of neurological dysfunction in rats after hepatic devascularization or thioacetamide treatment to induce acute liver failure. To facilitate repetitive removal of cerebrospinal fluid, a technique employing long-term implantation of cisterna magna catheters in conscious, freely moving rats was developed. Brain but not cerebrospinal fluid concentrations of the excitatory amino acids glutamate and aspartate were reduced in both animal models of fulminant liver failure in parallel with deterioration of neurological status. Brain and cerebrospinal fluid GABA levels were not significantly altered. Cerebrospinal fluid glycine levels were increased two to three times in parallel with increasing brain glycine content in the devascularized rat but were unchanged in thioacetamide-induced liver failure, suggesting distinct pathophysiological mechanisms in these two experimental situations. On the other hand, onset of coma in both animal models of fulminant liver failure was accompanied by significantly increased cerebrospinal fluid taurine levels. We suggest that such changes result from taurine release from astrocytes in brain into the extracellular fluid; this is consistent with taurine's role in the regulation of intracellular osmolarity in brain. Sequential measurements of amino acids in the cerebrospinal fluid of small rodents with indwelling cisterna magna catheters adds a useful new approach for exploring the neurobiology of hepatic encephalopathy in fulminant liver failure.


Selection of a new multidrug resistant cell line from Friend leukemia cells by short and cyclic exposures to high concentrations of daunorubicin. Resistance of tumor cells to cytotoxic agents can be due to the overexpression of the mdr 1 gene, which encodes a plasma membrane protein (P-glycoprotein). To understand the molecular basis of multidrug resistance, several laboratories have isolated cell lines resistant to doxorubicin, actinomycin D, vinca alkaloids and related agents. Many months or years of culture with gradually increasing concentrations of cytotoxic agents are necessary to obtain a resistant cell line. We selected a new multidrug resistant cell line (MELC-DRTL) by 24-hour cycles of exposure to relatively high concentrations of daunorubicin from sensitive Friend Leukemia cells. After each cycle, the residual live cells were expanded up to the density of 1 x 10(6) cells/ml. The assay conducted with MoAb C-219 showed a high expression on the membrane surface of P-glycoprotein in the MELC-DRTL line, but the fact that it was impossible to obtain a complete reversal of the resistance, even when using high concentrations of verapamil, suggests the presence of other mechanisms unrelated to the presence of P-glycoprotein. The kind of cellular resistance induction used in this experiment enabled us to obtain an MDR cell line in three months of culture.


Immunochemical investigation of insulinomas for islet amyloid polypeptide and insulin: evidence for differential synthesis and storage. An affinity purified antibody to fragment 14-29 of islet amyloid polypeptide (IAPP) has been prepared. This antibody, which does not cross-react with the related molecule calcitonin gene-related peptide, was used to investigate immunochemically the presence of IAPP in normal and neoplastic human pancreatic endocrine tissue. The pattern of IAPP staining in normal pancreas mirrors that of insulin, although slight differences were observed. In neoplastic tissue, IAPP was found in 16 out of 19 tumours that were positive for insulin, and was absent from one tumour negative for insulin. In some cases there were differences in the staining patterns of IAPP and insulin. These results suggest that the synthesis and secretion of IAPP and insulin are not inter-dependent and support the concept that IAPP has a discrete biological function. Islet amyloid polypeptide was found in six out of six insulinoma amyloid deposits, suggesting that the peptide is an invariable component of these deposits. Over-expression of IAPP, with aberrant processing and/or secretion, may be the causative factor for amyloid deposition in insulinomas and in the islets of type 2 (non-insulin dependent) diabetic patients. Investigation of patients with insulinomas and of insulin cells in culture and tissue sections may help to clarify the biological function of IAPP.


Immunohistochemical comparison of chromogranins A and B and secretogranin II with calcitonin and calcitonin gene-related peptide expression in normal, hyperplastic and neoplastic C-cells of the human thyroid. Normal and hyperplastic thyroid C-cells and 14 cases of medullary thyroid carcinoma were investigated immunohistochemically with antibodies against chromogranins A and B, secretogranin II, calcitonin and calcitonin gene-related peptide (CGRP). Normal and hyperplastic C-cells showed strong calcitonin and chromogranin A immunoreactivity whereas CGRP, chromogranin B and secretogranin II expression was less intense. Strong calcitonin and chromogranin A immunoreactivity was also found in the majority of tumour cells in medullary thyroid carcinoma. The CGRP, chromogranin B and secretogranin II staining observed was present in variable patterns. In some cases CGRP, chromogranin B and secretogranin II could only be demonstrated in isolated tumour cells with elongated processes suggestive of neuronal differentiation of these cells. The biological function(s) of the chromogranins/secretogranins remain(s) still unclear. There is evidence that these proteins are pro-peptides which give rise to functionally active compounds. Studies on normal C-cells and medullary thyroid carcinoma may elucidate the role of chromogranins/secretogranins in endocrine and neuronal cells.


Expression of leukocyte adhesion molecules (ICAM-1/LFA-1) related to clinical behaviour in B cell lymphomas. We investigated the expression of adhesion molecules of lymphocyte function-associated antigen-1 alpha (LFA-1 alpha) and its ligand intercellular adhesion molecule-1 (ICAM-1) on 74 well-characterized B cell lymphomas. The LFA-1 was expressed on B cell lymphomas (21/74; 28 per cent), but to a lesser degree than ICAM-1 which was highly expressed (48/74 cases; 64 per cent). From the results of bone marrow examination of 39 cases with B cell lymphomas, 13 of 16 cases with a lack of ICAM-1 molecule showed a higher incidence of marrow involvement, but nine of 23 cases with the expression of ICAM-1 molecule showed a lower incidence. These findings suggest that the lack of expression of the ICAM-1 molecule by B cell lymphomas correlates with bone marrow involvement by lymphoma cells (p < 0.05). Expression of the LFA-1 molecule appears not to correlate with marrow involvement (p < 0.05).


Expression of p170 protein in multiple myeloma: a clinical study. The expression of the p170 multidrug resistance protein by bone marrow plasma cells (BMPC) was assessed at clinical presentation in 53 patients with multiple myeloma (MM) using the C219 monoclonal antibody. Twenty-two of the 53 (41 per cent) patients had variable aliquots (1-60 per cent, median = 6 per cent) of p170+ BMPC by immunocytochemistry. Five of 10 patients studied using bivariate flow cytometry had both diploid and hyperdiploid (DNA index ranged from 1.2 to 1.5) BMPC with hyperdiploid clones having significantly greater p170 expression than diploid ones. Of the 37 patients evaluated for a response, 20 (54 per cent) had responded to induction chemotherapy. The presence of p170+ BMPC was a negative indicator for achieving response. The response rate was 75 per cent for p170- and 25 per cent for p170+ cases (p < 0.01), with no difference on the basis of treatment schedule (melphalan and prednisone, 24 patients; peptichemio, vincristine and prednisone, 13 patients). No difference in response and survival duration was found between p170+ and p170- patients. In six of nine patients studied both at diagnosis and following induction chemotherapy the p170+ BMPC% increased irrespective of the type of treatment or outcome.


Detection of c-erbB-2 activation in paraffin-embedded tissue by immunohistochemistry. Commercially available monoclonal antibodies were tested for their ability to detect increased levels of c-erbB-2 protein in formalin-fixed, paraffin-embedded breast carcinomas. Of five antibodies studied, four (TAB-250, CB11, 3B5, and N3/D10) showed strong cytoplasmic membrane reactivity in 23% (11 of 47) of routinely processed tumors, although interpretation of the immunoreactivity with 3B5 and N3/D10 occasionally was difficult due to cytoplasmic granular staining. Since the c-erbB-2 oncogene is activated by DNA amplification and overexpression of mRNA and protein, the same tumors were analyzed for c-erbB-2 activation by other techniques. c-erbB-2 activation in these 11 tumors was confirmed by immunohistochemistry of frozen tissue (nine of nine tumors), in situ hybridization (nine of 11 tumors), and Southern blot analysis (five of eight tumors). In some of these tumors the failure to demonstrate c-erbB-2 DNA amplification may be due to the small percentage of malignant cells. One additional tumor showed probable c-erbB-2 protein overproduction based on strong immunoreactivity with two antibodies (TAB-250 and CB11), although no definite activation could be demonstrated by additional techniques. Three other tumors (6%) showed equivocal c-erbB-2 protein overproduction based on weak immunoreactivity only with TAB-250, although unequivocal activation could not be demonstrated by additional techniques. The 32 carcinomas (68%) that showed no significant immunoreactivity with any antibodies in routinely processed tissue also showed no detectable c-erbB-2 activation by additional techniques. We conclude that TAB-250 and CB11 are reliable antibodies for detecting c-erbB-2 protein overproduction in routinely processed tissue. TAB-250 also weakly stains a few tumors showing no definite c-erbB-2 activation by other techniques. Two additional antibodies (3B5 and N3/D10) detect c-erbB-2 protein overproduction in paraffin-embedded tissue, but are more difficult to interpret. A fifth antibody, TA-1, is an excellent reagent for use on frozen tissue, but prolonged formalin fixation may impair recognition of its antigenic epitope.


Elevated CD4 antigen expression among activated T cells in lymph nodes draining mammary regions chronically exposed to Staphylococcus aureus antigen. We examined the cell cycle distribution and subset marker characteristics of mucosal-associated supramammary lymph node (MALN) T cell subpopulations at sites proximal and distal to the mammary region of animals repeatedly injected with Staphylococcus aureus antigen. Multiparameter flow cytometric analysis of draining MALNs showed that CD4+ T cells expressed significantly greater amounts of CD4 surface antigen than corresponding cell populations in non-draining MALNs. In contrast, the intensity of CD8 surface antigen expression among draining MALN CD8+ cells remained unchanged. Draining and non-draining MALNs contained nearly equal proportions of large CD4+ T cell subpopulations (CD4/CD8 ratio) with the former having greater cell numbers undergoing active DNA synthesis (S + G2M phase) in vivo. Similarly, draining MALNs had greater cell numbers of small CD4+ lymphocytes in the S + G2M phase, although with lower CD4/CD8 ratios of corresponding cell populations in non-draining MALNs. This study demonstrates that prolonged exposure with Staph aureus antigen enhances the cell number and expression of CD4 surface antigen among T lymphocyte subpopulations actively synthesizing DNA in draining MALNs. The role of the CD4 antigen in inflammatory responses at sites proximal (draining) and distal (non draining) to chronic infection within the mammary/mucosal immune network is discussed.


Various membrane proteins of Francisella tularensis induce interferon-gamma production in both CD4+ and CD8+ T cells of primed humans. Tularaemia is an intracellular infection, which is controlled by the host as a result of an immunospecific T-cell response. A crucial product of the responding T cells is interferon-gamma (IFN-gamma), which acts by enhancing the microbicidal activity of macrophages. T cells of tularaemia-vaccinated individuals respond in vitro to a multitude of protein antigens of the vaccine strain Francisella tularensis LVS. In the present study, the responses to four of these antigens were shown to be confined mostly to the CD45RO+ memory T-cell subset. To characterize further the phenotype of the responding cells, purified CD4+ and CD8+ T cells were stimulated with the antigens. CD4+ T cells, but not CD8+ T cells, proliferated and produced IFN-gamma. However, when CD8+ T cells were isolated from bulk cultures of lymphocytes, which had been stimulated with antigen for 3 days, they responded to an extent similar to that of CD4+ T cells. Purified CD8+ T cells also responded when they were supplemented with interleukin-2 (IL-2). There was a direct quantitative correlation between the proliferative response of CD4+ and CD8+ T cells and their production of IFN-gamma. IL-2 was produced in the cultures, the amounts being higher in the cultures of CD4+ than in those of CD8+ cells. IL-4 was not detected in the culture medium of any of the T-cell subsets. Seventeen human alpha beta + CD4+ CD8- CD3+ T-cell clones, specific to antigens of F. tularensis, were raised. When proliferating, these clones did invariably produce IL-2 and IFN-gamma but no IL-4. In conclusion, both CD4+ and CD8+ T cells of tularaemia-vaccinated individuals respond with proliferation to various protein antigens of F. tularensis, and the proliferative response is strictly associated with IFN-gamma production. The CD8+ T-cell response seems to depend on cytokines supplied by proliferating CD4+ T cells.


A T-cell response to the anti-arthritic drug penicillamine in the mouse: requirements for generation of the drug-derived antigen. Mice primed with the anit-arthritic drug D-penicillamine (DP) developed DP-specific T cells in the draining lymph nodes (DLN) which responded to drug-haptenated stimulator cells, but not to untreated control cells nor to free drug, in in vitro proliferation assays. The responder cells were CD4+ and the response was major histocompatibility complex (MHC) class II restricted. The conditions required to generate efficient stimulator cells for in vitro proliferation assays were investigated. Drug-haptenated syngeneic spleen cells, but not thymocytes, were able to stimulate T cells from DP-sensitized mice. However, prolonged incubations of spleen cells with DP were required to generate the drug-derived T-cell antigen. Further experiments revealed that the generation of a DP-derived antigenic determinant for T cells did not require intracellular processing, as stimulator cells pretreated with fixative or lysosomotropic agents before drug haptenation were as effective as untreated DP-haptenated cells in stimulating the responder cells to proliferative in vitro. These findings show that the protein-reactive drug DP can generate a cellular antigen that is capable of stimulating a T-cell response. Furthermore, the generation of this antigen appears to bypass conventional antigen processing, suggesting perhaps a direct chemical modification of cell surface molecules that are involved in immune recognition. This process may underlie adverse reactions to DP that are believed to be mediated by the cellular immune system.


Lymphokine secretion and proliferation of intraepithelial lymphocytes from murine small intestine. Compared to other peripheral lymphocytes, intestinal intraepithelial lymphocytes (IEL) have previously been shown to have low proliferative capabilities. However, there are two main populations of IEL in the small intestine of mice. First, there is the thymus-dependent CD3+,Thy-1+ population, most of which expresses the alpha beta T-cell receptor (TcR), and second there is the thymus-independent CD3+,Thy-1- population, most of which expresses the gamma delta TcR. In this study Thy-1-enriched and Thy-1-depleted lymphocytes from murine intestinal epithelium were studied separately for their ability to proliferate and secrete lymphokines in vitro after mitogenic stimulation, after stimulation via the TcR-CD3 complex and after stimulation with the superantigen Staphylococcus aureus B (SEB). Here we show that Thy-1-enriched IEL are not an immunocompromised population of cells but are functionally competent T cells that are capable of proliferation and lymphokine secretion after stimulation with concanavalin A (Con A), phorbol myristate acetate (PMA) and anti-CD3 monoclonal antibody (mAb). Furthermore, Thy-1-enriched IEL proliferate and secrete lymphokines after 'superantigenic' stimulation with SEB. In contrast, the majority of Thy-1-depleted IEL do not proliferate, and secrete only minimal levels of lymphokine to any of the stimuli tested in this study.


A clonal analysis of lung T cells derived by bronchoalveolar lavage of healthy individuals. The characteristics of the T-cell population in the healthy human lung have been investigated by analysing the properties of T-cell clones derived from bronchoalveolar lavage (BAL) samples and comparing them with T cells cloned from the blood of the same individuals. The proportions of CD4+ and CD8+ T cells in the starting populations from BAL and blood were similar although only 14% of BAL T cells were CD45RA+ compared to 70% of blood T cells. The precursor frequency of T-cell clones derived from BAL was less than from blood. The cytokine profiles [after phytohaemagglutinin (PHA) stimulation] of the clones derived from both sources were markedly different and these differences lay in the CD4+ population. BAL-derived CD4+ clones produced interferon-gamma (IFN-gamma) more frequently than did those from blood while blood-derived clones were more likely to produce interleukin-2 (IL-2) than those from BAL. IL-4 was produced by the majority of BAL- or blood-derived clones (93% and 88% respectively) either along with IFN-gamma (BAL) or IL-2 (blood). The cytokine profiles of BAL-derived T-cell clones are consistent with those derived from lung interstitium and suggest that the BAL T-cell populations reflect those in the lung wall. Whether the unique properties of lung T cells are acquired after leaving the blood or whether there is selective entry of T-cell subpopulations into the lung remains to be determined.


In vivo inhibition by a monoclonal antibody to CD4+ T cells of humoral and cellular immunity in sheep. The ability of intravenously injected anti-CD4 and anti-CD8 monoclonal antibody (mAb) to deplete specific lymphocyte subsets in vivo and their effects on antibody responses to ovalbumin (OVA) and Brucella abortus, and skin reactivity to T-cell mitogens was examined in merino lambs. Repeated administration of anti-CD4 or anti-CD8 mAb caused a specific and sustained depletion of target cells from peripheral blood. Anti-CD4 mAb significantly inhibited the in vivo antibody response to OVA but had no effect on the antibody response to LPS of B. abortus. In contrast, antibody responses to both OVA and B. abortus lipopolysaccharides (LPS) remained unaffected in lambs depleted of their CD8+ T lymphocytes. These results confirm the T-cell dependence and independence of antibody responses to OVA and LPS, respectively. Skin reactions elicited by intradermal injections of phytohaemagglutinin (PHA) and concanavalin A (Con A) were also significantly suppressed in lambs depleted of their CD4+ T cells, but treatment with anti-CD8 mAb had no effect on skin responsiveness. Together, these results suggest that mAb can be extremely effective at selectively depleting lymphocyte subsets in vivo and can be used for studying various aspects of immunoregulation and immunity in sheep.


CD26 induces T-cell proliferation by tyrosine protein phosphorylation. CD26 antigen distribution among lymphoid cells and its participation in the process of lymphocyte activation and proliferation has been widely documented. However, the molecular and biochemical mechanisms coupled to the CD26 molecule are not yet known. With different monoclonal antibodies (mAb) we have detected that approximately 56% of CD4+ and 35% of CD8+ cells from peripheral blood lymphocytes express CD26 and the expression of this antigen is required for antigen- but not for mitogen-induced proliferation unless exogenous interleukin-2 (IL-2) is added to the culture. The stimulation of nylon wool-separated T cells and T-cell clones by the anti-CD26 mAb, 134-2C2, induced tyrosine phosphorylation on a subset of proteins of 50,000, 46,000, 26,000, 24,000 and 21,000 MW. This pattern of phosphorylation was not affected by the presence of 12-myristate 13-acetate (PMA), although this cofactor is required for CD26-mediated IL-2 mRNA expression and T-cell proliferation. When a specific tyrosine kinase inhibitor, Tyrphostin, was used in CD4+ cells cultures stimulated with 134-2C2 and PMA, the proliferation and the expression of IL-2 mRNA were inhibited. Thus, protein tyrosine phosphorylation seems to play a major role in CD26-mediated T-cell proliferation.


Rapid cytokine up-regulation of integrins, complement receptor 1 and HLA-DR on monocytes but not on lymphocytes. Short-term (3 hr) incubation of whole blood with human recombinant cytokines induced rapid changes in the expression of monocyte but not of lymphocyte surface molecules. The percentage of monocytes bearing CD11b molecules was enhanced by tumour necrosis factor-beta (TNF-beta), whilst that of CD11c was increased by both TNF-alpha and TNF-beta. The mean fluorescence intensity (MFI) of monocyte CD11a was enhanced by interleukin-2 (IL-2), TNF-alpha and TNF-beta, and that of CD11b, CD11c and CD18 was increased by IL-2, IL-4, TNF-alpha and TNF-beta. The proportion of monocytes expressing HLA-DR antigens was not modified by the cytokines investigated, but its MFI was increased by IL-2, IL-4, TNF-alpha and TNF-beta. In contrast, the percentage of monocytes bearing complement receptor 1 (CD35) was enhanced by IL-2, TNF-alpha and TNF-beta but the MFI of this molecule was not modified by these cytokines. The highest up-regulation of CD18, HLA-DR and CD35 was observed with 100 U/ml of either IL-2, IL-4, TNF-alpha or TNF-beta. Decreasing the concentration of all four cytokines from 100 to 10 and 1 U/ml diminished the levels of expression of all molecules, with the exception of CD35, which reached its maximum upon incubation with 1 U/ml of TNF-alpha. IL-1 beta, IL-6 or interferon-gamma (IFN-gamma) did not modify the expression of any of the above monocyte surface determinants. Moreover, none of the lymphocyte surface molecules investigated was modified by 3-hr incubation of blood with cytokines. The demonstration that cytokines selectively and rapidly up-regulate integrins, complement receptor 1 and HLA-DR molecules, on monocytes but not on lymphocytes, suggests that similar mechanisms of mononuclear cell activation by cytokines may control the development and duration of the inflammatory process.


Functional characterization of protective CD4+ T-cell clones reactive to the murine malaria parasite Plasmodium chabaudi. Protective immunity to asexual malaria parasites appears to be mediated predominantly by the CD4+ subset of T lymphocytes. To examine the role of this T-cell population in the immune response to the murine malaria parasite Plasmodium chabaudi, CD4+ clones derived from infected mice were raised and propagated in vitro. Analysis of the reactivity of clones responsive to parasite antigen demonstrated that the CD4+ cell response is heterogeneous and is consistent with the idea of two functionally distinct CD4+ subsets. Those populations derived early during primary infection secreted interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) upon antigenic stimulation in vitro, i.e. they had a cytokine repertoire typical of the delayed-type inflammatory T-helper 1 (Th1) CD4+ subset. In contrast, cells taken after clearance of a secondary infection produced IL-4 and acted as effective helper cells for anti-malarial antibody (Ab) synthesis in vitro, and thereby had the characteristics of Th2 cells. The appearance in vivo of Th1 and then Th2 clones specific for P. chabaudi-parasitized erythrocytes (pRBC) supports the proposal from limiting culture analyses that for this malaria parasite resolution of primary parasitaemia is predominantly through the action of cytokines rather than Ab, and that final clearance requires helper cells and specific immunoglobulin.


Effects of PMA, cytokines and dexamethasone on the expression of cell surface Fc receptors and mRNA in U937 cells. Fc receptors (FcR) are of importance in immune and inflammatory reactions. FcR expression as mRNA and surface protein was therefore examined in the myelomonocytic cell line, U937, after stimulation with phorbol ester (PMA), in the presence of seven different cytokines (interferon-gamma [IFN gamma], IFN alpha, granulocyte-macrophage colony-stimulating factor [GM-CSF], tumour necrosis factor-alpha [TNF alpha], TNF beta, interleukin-beta [IL-1 beta], IL-2) or dexamethasone. HLA class I and CD11b expression were also examined. Cell surface expression of FcRI and II was measured by flow cytometry using monoclonal antibodies, and the mRNA of FcRII was measured with cDNA or oligonucleotide probes. The major findings were: PMA increased cell surface FcRI, FcRII and CD11b, but decreased HLA; PMA caused a fivefold increase in all three FcRII RNA transcripts (2.5, 1.5 and 0.9 kb) in Northern analysis; IFN gamma, IFN alpha and GM-CSF increased the expression of FcRI and II, and there was no effect with IL-1 beta, IL-2, TNF alpha or TNF beta (only GM-CSF increased the expression of CD11b); all cytokines further increased FcRI and FcRII expression in the presence of PMA; HLA expression was also increased in the presence of PMA, IFN alpha and IFN gamma; dexamethasone reduced the levels of FcRI and II in cells stimulated with PMA with or without cytokines. Thus stimulatory agents and cytokines can alter the expression of surface Fc gamma R and mRNA encoding FcRI or II, providing potential control mechanisms for the modulation of these receptors in inflammatory responses.


Larvivorous potential of some indigenous fishes of Sherthallai region with special reference to their efficacy in control of mansonioides. Larvivorous potential of some indigenous fishes collected from natural habitats of Sherthallai region in Kerala state, India, was studied under laboratory as well as controlled field conditions. Ophiocephalus striatus was observed to consume significantly higher number of mansonioides larvae (354/g body wt/day), followed by Macropodus cupanus (231/g body wt/day). The proportion of adult vector mosquito emergence was significantly (P less than 0.05) lower in cages with fish species studied, as compared to that of control group of cages without fishes. Natural food preference of the selected fish species was also studied indirectly through gut content analysis.


Role of hypothalamic-renal noradrenergic systems in hypotensive action of potassium. To clarify the role of the renal and hypothalamic noradrenergic systems in the antihypertensive actions of dietary potassium supplementation in salt-loaded spontaneously hypertensive rats (SHR), we measured systolic blood pressure and norepinephrine turnover, which was determined from the rate of decline of tissue norepinephrine concentration after the administration of alpha-methyl-p-tyrosine, in 5-week-old SHR or age-matched Wistar-Kyoto (WKY) rats eating normal-NaCl (0.66%) or high-NaCl (8%) diet with supplementation of 8% KCl. In WKY rats, neither high-sodium nor high-potassium diets had an effect on blood pressure with no change in renal or hypothalamic norepinephrine turnover. In SHR, however, salt loading accelerated the development of hypertension. Potassium supplementation did not affect blood pressure in normal-sodium SHR but attenuated the rise in blood pressure with salt loads. Correspondingly, renal norepinephrine turnover in SHR was increased compared with that of WKY rats, and salt loading further potentiated the increased turnover in the kidney; however, no changes in hypothalamic turnover occurred. Potassium supplementation attenuated the rise in blood pressure with salt loads and the increased renal turnover. Stimulation of sympathetic discharge by cold exposure after the administration of alpha-methyl-p-tyrosine produced marked depletion of norepinephrine in most tissues. The loss of norepinephrine was significantly greater in both kidney and hypothalamus of salt-loaded SHR than in those of normal-sodium SHR, but potassium could normalize this. Thus, potassium not only diminished the increased renal norepinephrine turnover in the kidney under normal conditions but also attenuated the augmented renal and hypothalamic norepinephrine turnover by cold stress in salt-loaded SHR.(ABSTRACT TRUNCATED AT 250 WORDS)


Effects of alcohol and caloric restrictions on blood pressure and serum lipids in overweight men. We have examined the independent and combined effects on blood pressure and blood lipids of alcohol restriction and weight loss in overweight male drinkers with a view to assessing overall effects on cardiovascular risk of two widely promoted nonpharmacological approaches for hypertension. Eighty-six men with a mean age of 44.3 years, a mean regular alcohol intake of 440 ml/wk (five or six standard drinks per day), a mean blood pressure of 137.4 mm Hg systolic and 84.8 mm Hg diastolic, and a mean body mass of 92.5 kg entered a controlled two-way factorial study. The subjects were randomly assigned to four groups for an 18-week intervention in which members of two groups drank only low-alcohol beer, thereby reducing their alcohol intake by 374 ml/wk, while those of the other two groups continued their normal alcohol intake. Within the low and normal alcohol intake groups subjects either continued their usual diet or reduced their caloric intake by 4,200-6,300 kJ/day (1,000-1,500 kcal/day) (with protein, fat, and carbohydrate provided as 15%, 30%, and 55% of total calories, respectively). Calorie reduction and alcohol restriction caused weight losses of 7.5 (p less than 0.001) and 2.1 (p less than 0.01) kg, respectively. Calorie reduction and alcohol restriction were associated with decreases in systolic blood pressure of 5.4 (p less than 0.001) and 4.8 (p less than 0.01) mm Hg, respectively, and in diastolic blood pressure of 4.2 (p less than 0.001) and 3.3 (p less than 0.01) mm Hg, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)


Realizing the potential of practice pattern profiling. In January 1992, the Physician Payment Review Commission held a conference to learn about the appropriateness of present uses of profiling of practice patterns, and to identify what will be required to realize the full potential of this technique in the future. The conference addressed the data needs of profiling, the development of valid and relevant profiles, the impact of profiles on medical practice, and controversies surrounding public access to profiling information and the uses to which profiling has been put. This paper, based in part on that conference, reviews the basic concepts that underlie profiling and describes the roles that profiling can play in quality improvement, assessment of provider performance, and utilization review. It uses case studies to illustrate the types of problems that have arisen in actual usage and discusses what will be required to resolve them. The final section describes the roles that profiling can play in achieving the goals of health care reform, and concludes with what is needed in data and infrastructure development to improve the quality and usefulness of profiling.