Estimates of life history parameters in a high latitude, arid-country vervet monkey population

We present data on life history parameters from a long-term study of vervet monkeys in the Eastern Cape, South Africa. Estimates are presented of age at first conception for females and age at natal dispersal for males, along with the probability of survival to adulthood for infants born during the study, female reproductive life-span, reproductive output (including lifetime reproductive success for a subset of females), and inter-birth interval (IBI) duration. We also assess the effect of maternal age and infant survival on length of IBI. We then go on to compare life history parameters for our population with those from two East African populations in Kenya (Amboseli and Laikipia). We find there is broad consensus across the three populations, although mean infant survival was considerably lower for the two East African sites. Such comparisons must be made cautiously, however, as local ecology across the duration of the studies obviously has an impact on the estimates obtained. With this caveat in place, we consider that the concordance between values is sufficient to enable the values reported here to be used in comparative studies of primate life history, although data from habitats with higher rainfall and lower levels of seasonality are needed, and the results presented here should not be seen as canonical.

Antimicrobial resistance profile of Escherichia coli isolated from poultry litter

Antimicrobial resistance is a threat to animal and human health. As a commensal and zoonotic bacterium, Escherichia coli has the potential to be a pathogenic source of antimicrobial resistance. The purpose of this study aimed to investigate the antimicrobial resistance profile of E. coli isolated from litter collected from pens in a broiler chicken experiment. E. coli was isolated from litter samples (n = 68 isolates) of 16 pens housing broilers to d 53 of age. Resistance to 10 antimicrobials was observed by disc diffusion. The presence of 23 antimicrobial and heavy metal resistance genes, O serogroups, and avian pathogenic E. coli (APEC-like) minimal predictor genes were identified through PCR. E. coli isolates presented the greatest resistance to cephalothin (54.4%), tetracycline (27.9%), streptomycin (29.4%), ampicillin (20.6%), colistin (13.2%), sulphonamides (8.8%), and imipenem (1.5%). Multidrug resistance to at least 3 antimicrobials was observed in 22.1% of isolates. The identified O-types of the E. coli isolates were O15, O75, O78, and O91. There was a greater likelihood that the genes groEL, aph(3)IA, silP, sull, aadA, qacEdelta1, iroN, ompTp, and hlyF were present in isolates that exhibited ampicillin resistance (P ≤ 0.05). There was a greater likelihood that the groEL gene was present in isolates resistant to ampicillin, colistin, tetracycline, sulphonamides, or cephalothin (P ≤ 0.05). Further characterizing E. coli antimicrobial resistance is essential and aids in developing effective solutions, thereby furthering the One Health objective.

Novel psychoactive substances: What educators need to know

Novel psychoactive substances (NPS) are synthetic, psychoactive drugs that are generally not under international regulatory control. NPS are frequently sold as alternatives to classic "street drugs" such as ecstasy or LSD. However, little is known about their pharmacology and toxicity and they therefore pose unknown health risks. Further, risk for harms are elevated because users often do not know what they are taking, and therefore cannot predict dose, potency, or other potential properties.

Risk factors for invasive meningococcal disease in southern Queensland, 2000-2001

AIM

The aim of this paper is to describe the risk factors for invasive meningococcal disease (IMD) in southern Queensland.

METHODS

A case control study during the calendar years 2000-2001 was undertaken.

RESULTS

Eighty-four laboratory-confirmed cases of IMD were notified. Four patients died and were excluded from the present study. Sixty-two (78%) eligible cases and 79 controls selected from the same age group and medical practice as cases, were interviewed. Univariate analysis found that IMD was associated with sharing bedrooms with two or more people (odds ratio (OR) 4.3; 95% confidence interval (CI) 1.2-17.0, P = 0.01), any exposure to tobacco smoke (smoker or passive exposure; OR 2.3; 95% CI 1.1-4.8, P = 0.02), passive exposure to tobacco smoke (OR 2.4; 95% CI 1.0-5.6, P = 0.03) and recent upper respiratory tract infection (OR 1.9, 95% CI 0.9-4.1, P = 0.06). Children who were breast-fed were less likely to develop IMD (OR 0.3; 95% CI 0.1-1.1, P = 0.04). Attendance at a childcare centre was not associated with an increased risk of IMD. In multivariate analysis, IMD was associated with children under 6 years of age who shared a bedroom with two or more people (OR 7.4; 95% CI 1.5-36.1, P = 0.01) or who had a primary carer who smoked (OR 9.1; 95% CI 2.1-39.9, P = 0.003).

DISCUSSION

This is the second Australian study that identifies links between risk of IMD and exposure to cigarette smoke. The risk of IMD in young children could be further reduced if primary caregivers did not smoke. This information may contribute a new perspective to antismoking campaigns.

Design, docking, and evaluation of multiple libraries against multiple targets

We present a general approach to the design, docking, and virtual screening of multiple combinatorial libraries against a family of proteins. The method consists of three main stages: docking the scaffold, selecting the best substituents at each site of diversity, and comparing the resultant molecules within and between the libraries. The core "divide-and-conquer" algorithm for side-chain selection, developed from an earlier version (Sun et al., J Comp Aided Mol Design 1998;12:597-604), provides a way to explore large lists of substituents with linear rather than combinatorial time dependence. We have applied our method to three combinatorial libraries and three serine proteases: trypsin, chymotrypsin, and elastase. We show that the scaffold docking procedure, in conjunction with a novel vector-based orientation filter, reproduces crystallographic binding modes. In addition, the free-energy-based scoring procedure (Zou et al., J Am Chem Soc 1999;121:8033-8043) is able to reproduce experimental binding data for P1 mutants of macromolecular protease inhibitors. Finally, we show that our method discriminates between a peptide library and virtual libraries built on benzodiazepine and tetrahydroisoquinolinone scaffolds. Implications of the docking results for library design are explored.

Esophageal reconstruction for benign disease: self-assessment of functional outcome and quality of life

BACKGROUND

Little information exists regarding functional outcome and quality of life after esophagectomy and subsequent esophageal reconstruction for benign disease as evaluated by the patients themselves.

METHODS

Eighty-one patients completed a combined two-part questionnaire regarding esophageal function and quality of life (MOS SF-36) a median of 9.8 years (range, 10 months to 18.9 years) after esophageal reconstruction for benign disease. There were 43 men (53.1%) and 38 women (46.9%). Median age at time of esophageal reconstruction was 51 years (range, 6 to 78 years). Intestinal continuity was established with stomach in 58 patients (71.6%), colon in 16 patients (19.8%), and small bowel in 7 patients (8.6%).

RESULTS

Dysphagia to solids was present in 48 patients (59.3%) and 27 patients (33.3%) required at least one postoperative dilatation. Heartburn was present in 50 patients (61.7%) which required medication for control in 37 patients (45.7%). The number of meals per day was three to four in 58 patients (71.6%), more than four in 15 patients (18.5%), less than three in 6 patients (7.4%), and unknown in 2 patients (2.5%). The size of each meal was smaller than preoperatively in 46 patients (56.8%), larger in 22 patients (27.2%), unchanged in 12 patients (14.8%), and unknown in 1 patient (1.2%). The number of bowel movements per day increased in 37 patients (45.7%), was unchanged in 36 patients (44.4%), and decreased in 8 patients (9.9%). Resection for perforation was associated with smaller postoperative meals compared with resection for stricture (p < 0.05). Age, sex, and type of esophageal reconstruction did not affect late functional outcome. Regarding quality of life, physical functioning, social functioning, and health perception were decreased (p < 0.05). No significant change was observed in role-physical, mental health, bodily pain, energy/fatigue, and role-emotional scores.

CONCLUSIONS

Self-assessment of postoperative esophageal symptoms after esophagectomy and reconstruction for benign disease demonstrates that symptoms are frequently present at long-term follow-up and unaffected by the type of reconstruction.

Esophageal reconstruction for benign disease: early morbidity, mortality, and functional results

BACKGROUND

Esophagectomy for benign disease is performed infrequently. We reviewed the Mayo Clinic's experience with patients who required esophageal reconstruction for benign esophageal disease.

METHODS

From March 1956 to October 1997, all patients who required resection and reconstruction for a benign condition of the esophagus were reviewed.

RESULTS

There were 255 patients (141 male, 114 female). Median age was 55 years (range, 2 to 100). The original diagnosis was an esophageal stricture in 108 patients (42%), primary motility disorder in 84 (33%), perforation in 36 (14%), hiatal hernia in 18 (7%), and other in 9 (4.0%). Reconstruction was with stomach in 168 patients (66%), colon in 70 (27%), and small bowel in 17 (7%). The anastomosis was intrathoracic in 144 patients (57%) and cervical in 111 (43%). There were 13 postoperative deaths (mortality 5%); 142 patients (56%) had at least one complication. Median hospitalization was 14 days (range, 6-95 days). Follow-up was complete in 226 patients (88.6%) for a median of 52 months (range, 1 month to 29 years). A total of 175 patients (77.4%) were improved. Functional results were classified as excellent in 72 patients (31.8%), good in 23 (10.2%), fair in 80 (35.4%), and poor in 51 (22.6%).

CONCLUSIONS

Esophageal reconstruction for benign disease resulted in functional improvement in a majority of patients. It can be done with low mortality and acceptable morbidity. Early morbidity is adversely affected by the diagnosis of perforation and the route through which the conduit is placed. Late functional outcome is adversely affected by the diagnosis of paraesophageal hernia and a cervical anastomosis.

Videoendoscopic thoracic aorta-to-femoral artery bypass in the pig

BACKGROUND

The thoracoscopic approach to the aorta has the advantages of easy aortic dissection, excellent inflow, improved exposure in the thorax without insufflation, and ability to employ both laparoscopic and traditional instruments. Our aim was to develop a thoracoscopic technique for descending thoracic aorta-to-femoral artery bypass (TAFB) in the pig that results in acceptable short-term survival and graft patency.

MATERIALS AND METHODS

Thoracoscopic TAFB was performed in 11 pigs. Using two-lung ventilation, the animals were placed in a 45 degrees left lateral semidecubitus position. A fan lung retractor, two dissecting ports, intercostal artery loops, and camera were placed through five 10- to 20-mm thoracoscopic incisions. After aortic dissection, an 8-mm graft was passed through a retroperitoneal tunnel. Rumel tourniquets were used for aortic occlusion after placement of a shunt. End-to-side endoscopic anastomosis was completed with knots tied extracorporeally. The left femoral anastomosis was completed under direct vision. Duplex ultrasound of the graft was done on postoperative days 1, 3, and 7.

RESULTS

Thoracoscopic TAFB was completed in all animals. Mean aortic anastomosis time was 57 min (range, 34-145); and mean cross-clamp time, 74 min (range, 53-155). Mean operative time was 310 min; the first six operations lasted longer than the last five (338 min vs 276 min, P < 0.04). Average blood loss was 611 ml (range, 250-1300). Two animals died due to anesthetic complications. One (11%) of the nine surviving pigs died on day 2 due to bleeding. Complications were paraplegia in one (11%) and graft thrombosis in another (11%).

CONCLUSIONS

Videoendoscopic TAFB can be completed in pigs with acceptable short-term patency and survival. Further experience in thoracoscopic techniques can make TAFB a feasible and low-risk option for selected patients with aortoiliac occlusive disease.

High throughput protein fold identification by using experimental constraints derived from intramolecular cross-links and mass spectrometry

We have used intramolecular cross-linking, MS, and sequence threading to rapidly identify the fold of a model protein, bovine basic fibroblast growth factor (FGF)-2. Its tertiary structure was probed with a lysine-specific cross-linking agent, bis(sulfosuccinimidyl) suberate (BS(3)). Sites of cross-linking were determined by tryptic peptide mapping by using time-of-flight MS. Eighteen unique intramolecular lysine (Lys-Lys) cross-links were identified. The assignments for eight cross-linked peptides were confirmed by using post source decay MS. The interatomic distance constraints were all consistent with the tertiary structure of FGF-2. These relatively few constraints, in conjunction with threading, correctly identified FGF-2 as a member of the beta-trefoil fold family. To further demonstrate utility, we used the top-scoring homolog, IL-1beta, to build an FGF-2 homology model with a backbone error of 4.8 A (rms deviation). This method is fast, is general, uses small amounts of material, and is amenable to automation.

NMDA and AMPA glutamate receptor subtypes in the thoracic spinal cord in lean and obese-diabetic ob/ob mice

Quantitative autoradiography was used to characterise the binding of selective radiolabelled antagonists for the N-methyl-D-aspartate (NMDA) receptor and the alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) receptor in the dorsal, intermediate and ventral subregions of the grey matter of the upper thoracic spinal cord in male and female lean and obese-diabetic (ob/ob) mice. The density of binding sites for both receptor subtypes was greater in diabetic mice, in all three subregions of the grey matter, than the corresponding subregions in the lean mice. The affinity of the binding site for the NMDA antagonist was significantly higher in obese mice than lean mice, consistent with the presence of two subpopulations of NMDA receptors with different ligand binding affinities in obese mice. The increase in expression of the glutamate receptor subtypes, and altered ligand affinity for the NMDA receptor subtype in the obese mice may be causally involved in the peripheral neuropathies which can accompany diabetes mellitus.

Effect of sympathectomy on the expression of NMDA receptors in the spinal cord

The expression of NMDA receptors in the intermediolateral (IML) region of the upper thoracic spinal cord, was studied in 3 week old rats. The effect of section of the cervical sympathetic nerve on neuronal cell number and receptor expression was examined up to two weeks after the operation. Age-matched sham-operated and unoperated animals were used as controls. It was shown using quantitative autoradiography with the NMDA receptor antagonist [(3)H]MK-801 (dizocilpine maleate), that there was a marked downregulation of receptors in all groups of animals, beginning at approximately 4 weeks of age. However after sympathectomy, which resulted in the death of 44% of neurones in the IML by 7 days, there was a significant increase in receptor density per neurone compared to sham-operated controls. In the control animals there was a significant increase in the Kd value of the binding between 21 and 24 days after birth indicating an increased expression of a low affinity receptor, but no such increase was seen after axotomy. The results are consistent with two populations of NMDA receptors being transiently expressed in the IML in developing animals, and the higher affinity receptor being down-regulated between 4 and 5 weeks of age. The presence of the high affinity receptor subtype may predispose neurones to die after axotomy.

Laparoscopic transureteroureterostomy: demonstration of its feasibility in swine

PURPOSE

To evaluate the feasibility of laparoscopic transureteroureterostomy (TUU) in a porcine model.

MATERIALS AND METHODS

Nine female pigs had bilateral ureteral stents placed 3 weeks prior to surgery. At surgery, a left-to-right laparoscopic TUU was performed. Ureteral stents were placed across the anastomosis in seven cases. Six weeks after surgery, the stents were removed. After an additional 3 weeks, an excretory urogram, retrograde ureteropyelogram, and ureteroscopic examination of the anastomosis were performed. Serum creatinine assay and urine cultures were performed at regular intervals. Antibiotic prophylaxis was used for 1 week after each procedure.

RESULTS

Of the nine animals, eight underwent successful laparoscopic TUU. Excretory urograms revealed prompt function and washout in all these cases. One animal developed an anastomotic stricture; in this animal, the ureters had remained nondilated after initial stent placement. Serum creatinine values remained within the normal range for all animals undergoing successful surgery. Additional complications included one urinary tract infection and one postoperative ileus, which were treated without difficulty. The operative time ranged from 2.5 to 6 hours, with shorter procedures later in the series.

CONCLUSIONS

Laparoscopic TUU is practical in the porcine model. It may prove to be an alternative to an open TUU in patients with lower ureteral lesions when ureteroneocystostomy is not feasible.

Lack of association between genetic variation in the beta3-adrenergic receptor gene and insulin resistance in patients with coronary heart disease

The beta-adrenergic system plays a critical role in regulating lipolysis and thermogenesis. Recent studies have suggested that a missense Trp64Arg mutation in the beta3-adrenergic receptor gene is involved in visceral obesity and insulin resistance. We investigated the effect of this mutation on insulin resistance in patients with angiographically documented coronary heart disease ([CHD]n = 137) and normal subjects (n = 188). Plasma glucose and insulin responses to a 75-g oral glucose tolerance test and insulin resistance measured by the insulin suppression test, were determined in 58 (42%) patients with CHD and 121 (64%) controls. The genotype and allele frequency of the beta3-adrenergic receptor did not differ between patients with CHD and controls. The blood pressure, body mass index (BMI), waist to hip ratio, fasting plasma glucose, insulin, and lipid, and plasma glucose and insulin responses to the glucose load were relatively similar in subjects with and without the mutation in CHD and normal groups. The degree of insulin sensitivity, ie, the steady-state plasma glucose concentration, was not significantly different between subjects with and without the mutation in the CHD group (11.3 +/- 1.2, n = 11 v 11.9 +/- 0.6 mmol/L, n = 47, P = NS) and control group (8.4 +/- 0.7, n = 30 v 8.2 +/- 0.4 mmol/L, n = 91, P = NS). We conclude that Trp64Arg polymorphism of the beta3-adrenergic receptor gene does not likely play a major role in the development of CHD in the Chinese population. In addition, it appears to have no association with the insulin resistance syndrome in either CHD or non-CHD subjects.

Troglitazone has no effect on red cell mass or other erythropoietic parameters

OBJECTIVE

Troglitazone is a new anti-diabetic agent for the treatment of type 2 diabetes. In placebo-controlled trials troglitazone improves glycaemic control, reduces hyperinsulinaemia and has beneficial effects on blood lipids. However, minor, reversible reductions in erythrocyte count, haemoglobin and haematocrit with no associated clinical symptoms have been observed in some troglitazone-treated patients. The primary objective of the present study was to determine if these changes could be explained by a decrease in red cell mass or change in plasma volume.

METHODS

Twenty-four healthy males were randomized in a double-blind manner to troglitazone (200 or 600 mg per day) or placebo for 6 weeks. Blood samples for the measurement of red cell mass and plasma volume were obtained in the 2 weeks prior to treatment and after 6 weeks of treatment. Reticulocyte and erythrocyte counts, haemoglobin and haematocrit were also measured.

RESULTS

At the end of the treatment period there were no statistically significant changes in red cell mass. Similarly there were no changes in reticulocyte count, erythropoietin or soluble transferrin receptors. These data indicate that troglitazone does not affect erythropoiesis. In addition, troglitazone was not associated with increased red blood cell destruction or haemolysis. There was a trend towards increased plasma volume in the troglitazone groups: increases of 2.5 ml x kg(-1) (5.7% increase) in the troglitazone 200 mg group and 3.4 ml x kg(-1) (7.8% increase) in the troglitazone 600 mg group were observed compared with placebo.

CONCLUSION

These data suggest that dilutional effects related to a modest increase in plasma volume may explain the haematological changes seen in other clinical trials with high doses of troglitazone, although this study has shown that the changes in plasma volume are not statistically significant.

A rapid method for exploring the protein structure universe

We have developed an automatic protein fingerprinting method for the evaluation of protein structural similarities based on secondary structure element compositions, spatial arrangements, lengths, and topologies. This method can rapidly identify proteins sharing structural homologies as we demonstrate with five test cases: the globins, the mammalian trypsinlike serine proteases, the immunoglobulins, the cupredoxins, and the actinlike ATPase domain-containing proteins. Principal components analysis of the similarity distance matrix calculated from an all-by-all comparison of 1,031 unique chains in the Protein Data Bank has produced a distribution of structures within a high-dimensional structural space. Fifty percent of the variance observed for this distribution is bounded by six axes, two of which encode structural variability within two large families, the immunoglobulins and the trypsinlike serine proteases. Many aspects of the spatial distribution remain stable upon reduction of the database to 140 proteins with minimal family overlap. The axes correlated with specific structural families are no longer observed. A clear hierarchy of organization is seen in the arrangement of protein structures in the universe. At the highest level, protein structures populate regions corresponding to the all-alpha, all-beta, and alpha/beta superfamilies. Large protein families are arranged along family-specific axes, forming local densely populated regions within the space. The lowest level of organization is intrafamilial; homologous structures are ordered by variations in peripheral secondary structure elements or by conformational shifts in the tertiary structure.

Antimutagens in food plants eaten by Polynesians: micronutrients, phytochemicals and protection against bacterial mutagenicity of the heterocyclic amine 2-amino-3-methylimidazo[4,5-f]quinoline

We have previously suggested that differences in cancer incidence between Polynesians (including Maoris and people from several Pacific islands) and Europeans in New Zealand may at least partially relate to differences in the species of food plants (fruits, vegetables and cereals) preferentially eaten by these groups. Twenty-five food plants that are typically eaten in different amounts by these two population groups were selected for detailed study. Antimutagenic properties of three extracts from each of the selected plants were investigated using a preincubation mutagenicity assay with Salmonella typhimurium strain TA1538 against the mutagenicity of the heterocyclic amine 2-amino-3-methylimidazo[4,5-f]quinoline (IQ). The data revealed strong antimutagenic properties in several of the food plants commonly eaten by Polynesians, especially rice, watercress, pawpaw, taro leaves, green banana and mango. Using the New Zealand food database, a number of nutrients and micronutrients with antimutagenic and anticarcinogenic potential were identified from the selected food plants. Some of these were tested for antimutagenic potential in parallel experiments to those done with the food plant extracts. Although some of these micronutrients are antimutagens against IQ, their concentrations in the food plants failed to explain the protection against mutagenicity found in the experiments with extracts of the food plants. Thus, other types of chemical, not identified in the database, must be leading to antimutagenesis. Possible active molecules include chlorophylls, carotenoids, flavonoids and coumarins, many of which are also known to be anticarcinogens. If human cancer data are to be interpreted in terms of cancer protection, these components need urgently to be quantified in food plants in the New Zealand diet, especially in those food plants eaten in large amounts by Polynesians.

Necrobiosis lipoidica: only a minority of patients have diabetes mellitus

Although it is commonly accepted that necrobiosis lipoidica (NL) is associated with diabetes mellitus (DM), there is some controversy regarding the degree of this association. In a retrospective review of 65 patients with NL attending our dermatology out-patient clinics we found that just seven (11%) were known to have DM at the time of presentation. Seven further patients (11%) were diagnosed as having impaired glucose tolerance/DM at presentation and over a 15-year follow-up period. Thus, only a minority of our patients with NL had DM.

Troglitazone increases the resistance of low density lipoprotein to oxidation in healthy volunteers

The oxidative modification of low density lipoprotein is of importance in atherogenesis. Antioxidant supplementation has been shown, in published work, to increase low density lipoprotein resistance to oxidation in both healthy subjects and diabetic subjects; in animal studies a contemporary reduction in atherogenesis has been demonstrated. Troglitazone is a novel oral antidiabetic drug which has similarities in structure with vitamin E. The present study assessed the effect of troglitazone 400 mg twice daily for 2 weeks on the resistance of low density lipoprotein to oxidation in healthy male subjects. Ten subjects received troglitazone and ten received placebo in a randomised, placebo-controlled, parallel-group design. The lag phase (a measure of the resistance of low density lipoprotein to oxidation) was determined by measurement of fluorescence development during copper-catalysed oxidative modification of low density lipoprotein. The lag phase was increased by 27 % (p < 0.001) at week 1 and by 24% (p < 0.001) at week 2 in the troglitazone treated group compared with the placebo group. A number of variables known to influence the resistance of low density lipoprotein to oxidation were measured. They included macronutrient consumption, plasma and lipoprotein lipid profile, alpha-tocopherol, beta-carotene levels in low density lipoprotein, low density lipoprotein particle size, mono and polyunsaturated fatty acid content of low density lipoprotein and pre-formed low density lipoprotein hydroperoxide levels in low density lipoprotein. Troglitazone was associated with a significant reduction in the amount of pre-formed low density lipoprotein lipid hydroperoxides. At weeks 1 and 2, the low density lipoprotein hydroperoxide content was 17% (p < 0.05) and 18% (p < 0.05) lower in the troglitazone group compared to placebo, respectively. In summary the increase in lag phase duration in the troglitazone group appeared to be due to the compound's activity as an antioxidant and to its ability to reduce the amount of preformed low density lipoprotein lipid hydroperoxides. This antioxidant activity could provide considerable benefit to diabetic patients where atherosclerosis accounts for the majority of total mortality.

Effect of the non peptide angiotensin II antagonist, GR117289C on the vasoconstrictor actions of angiotensin II in the human forearm

AIMS

GR117289C is a non peptide, selective angiotensin (AT1) receptor antagonist. The purpose of this study was to determine whether this agent, given orally, could attenuate the vasoconstrictor effects of angiotensin II(AII) infused locally into the forearm circulation in man.

METHODS

Eight healthy male subjects were studied on four occasions in a randomized, double-blind, placebo controlled, crossover study. Five hours (approximate time of peak dynamic effect) following dosing with GR117289C (300 mg, 100 mg, 10 mg or placebo), A II was infused in incremental doses (0, 0.1, 0.4, 1.6, 6.2, 25 and 100 pmol min-1) into the left brachial artery, each for 10 min. Forearm blood flow was measured using venous occlusion plethysmography.

RESULTS

GR117289C inhibits the vasoconstrictor effects of A II in a dose dependent manner. The active treatment: placebo ratios of forearm blood flow in the infused arm during the highest dose of AII (100 pmol min-1) were: GR117289C 10 mg, 1.12 (95% C.I. 0.81-1.55; P = 0.478), 100 mg, 1.43 (95% C.I. 1.01-2.01; P = 0.042) and 300 mg, 1.62 (95% C.I. 1.17-2.24; P = 0.006). There was no significant difference in blood pressure between each of the treatment groups and placebo.

CONCLUSIONS

GR117289C is a pharmacologically active, oral A II antagonist in healthy men.

Three keratin gene mutations account for the majority of dominant simplex epidermolysis bullosa cases within the population of Ireland

We have located three extended families in Ireland (population 3.5 million) with autosomal dominant simplex forms of Epidermolysis Bullosa (EBS). A mutation within the keratin type I (K14) gene (Met-->272-->Arg) in one family suffering from the generalized simplex (Koebner) form of the disease has been previously described (Humphries et al., Hum Mutat 2:37-42, 1993). Here we report on the identification of mutations within the remaining two families, both of whom suffer from the Weber-Cockayne form of the disease. These mutations, within the type II keratin (K5) gene, are Asn-->193-->Lys and Met-->327-->Thr. They have been shown in each case to co-segregate with the disease and are not present in the normal population. Within the three families, a total of 44 living persons with such mutations have been identified, providing a minimum prevalence estimate for the disease in the Irish population of approximately 1 in 80,000, compared to an overall estimated global incidence at birth for all forms of EB of 1 in 50,000. Therefore, these three mutations probably account for the majority of cases of EBS within this population.

Insulin resistance, glucose intolerance, and hyperinsulinemia in patients with microvascular angina

Plasma glucose and insulin responses to oral glucose and insulin-mediated glucose disposal were determined in 20 patients with microvascular angina and 20 normal volunteers who were similar in terms of age, gender distribution, and degree of obesity. Plasma glucose and insulin responses to a 75-g oral glucose challenge were significantly higher in those with microvascular angina (P < .001), as were steady-state plasma glucose concentrations after a 180-minute infusion of somatostatin, glucose, and insulin (12.2 +/- 1.0 v 7.6 +/- 0.6 mmol/L, P < .001). Since steady-state plasma insulin concentrations were similar in the two groups (627 +/- 32 v 631 +/- 29 pmol/L), these data indicate that patients with microvascular angina are insulin-resistant, glucose-intolerant, and hyperinsulinemic compared with a matched group of normal volunteers.

Putative cocaine receptor in striatum is a glycoprotein with active thiol function

Dopamine transporters of bovine and rat striata were identified by their specific [3H]cocaine binding and cocaine-sensitive [3H]dopamine [( 3H]DA) uptake. Both binding and uptake functions of bovine striatal transporters were potentiated by lectins. Concanavalin A (Con A) increased the velocity but did not change the affinity of the transporter for DA; however, it increased its affinity for cocaine without changing the number of binding sites. This suggests that the DA transporter is a glycoprotein and that Con A action on it produces conformational changes. Inorganic and organic mercury reagents inhibited both [3H]DA uptake and [3H]cocaine binding, though they were all more potent inhibitors of the former. n-Ethylmaleimide inhibited [3H]DA uptake totally but [3H]cocaine binding only partially. Also, n-pyrene maleimide had differential effects on uptake and binding, inhibiting uptake and potentiating binding. [3H]DA uptake was not affected by mercaptoethanol up to 100 mM, whereas [3H]cocaine binding was inhibited by concentrations above 10 mM. On the other hand, both uptake and binding were fairly sensitive to dimercaprol (less than 1 mM). The effects of all these sulfhydryl reagents suggest that the DA transporter has one or more thiol group(s) important for both binding and uptake activities. The Ellman reagent and dithiopyridine were effective inhibitors of uptake and binding only at fairly high concentration (greater than 10 mM). Loss of activity after treatment with the dithio reagents may be a result of reduction of a disulfide bond, which may affect the transporter conformation.

Treatment of sarcomas of the chest wall using intensive combined modality therapy

As part of two sequential protocols using intensive combined modality treatment in pediatric and adolescent sarcomas, 31 consecutive patients with primary chest wall tumors were treated between November 1977 and March 1986. This group included 13 patients with peripheral neuroepithelioma (Askin's tumor), 11 patients with Ewing's sarcoma, 3 patients with rhabdomyosarcoma, and 4 patients with undifferentiated sarcomas. Following complete work-up, 17 patients presented with localized disease and 14 patients presented with metastases. Patients received intensive combined modality treatment with combination chemotherapy (vincristine, cyclophosphamide, Adriamycin, +/- actinomycin-D and DTIC) and high-dose conventionally fractionated radiation therapy to the primary (55-60 Gy) and non-pulmonary metastases (45-50 Gy). Radiation techniques used for the primary chest wall tumor varied with the clinical presentation. Patients achieving a complete response received either low-dose fractionated TBI (1.5 Gy/0.15 Gy fx/5 weeks) or high-dose TBI (8 Gy/4 Gy fx/2 days) and an intensive cycle of chemotherapy followed by autologous bone marrow transplantation. Twenty-five of 31 patients were judged to have a complete response (including 1 patient with complete resection). With minimum follow-up of 6 months and median follow-up of 36 months from completion of treatment, 14 patients remain disease-free with 2 additional patients alive in second remission after relapse. Patients with localized disease at presentation have improved disease-free survival and overall survival compared to patients with metastases at presentation. All 17 localized patients achieved a CR and 11 are NED compared to 8 of 14 metastatic patients achieving a CR and only 3 are NED. There have been 5 loco-regional recurrences with 3 "in-field" failures and 2 failures in the regional pleura. There were no treatment-related deaths and no clinically significant cases of pneumonitis. To date, 2 patients have significant treatment related morbidity, including 1 patient with scoliosis requiring surgery and 1 patient with acute leukemia developing 42 months after the start of therapy (presently in remission). We conclude that this intensive combined modality therapy results in a high CR rate and good local control with acceptable morbidity. Patients with metastatic disease at presentation remain a therapeutic challenge.

Enhanced chemiluminescence production by phagocytosing neutrophils in psoriasis

Using serum-coated zymosan, the generation of reactive oxidants by measurement of chemiluminescence was shown to be significantly enhanced in isolated peripheral psoriatic neutrophils compared to normal controls. This response was observed irrespective of whether zymosan was opsonized with fresh autologous or normal AB serum. However, this increased activity was reduced with zymosan was opsonized with serum that was preheated at 56 degrees C for 30 min. There was no statistical correlation of chemiluminescence activity with degranulation of beta-glucuronidase in either normal or psoriatic subjects. In addition, chemiluminescence produced by normal cells was significantly increased when zymosan was opsonized with psoriatic serum. The plasma membrane-bound enzyme, NAD(P)H oxidase, which produces superoxide in response to phagocytic stimulation, was significantly increased in psoriatic neutrophils compared to normal controls. These data add further evidence for activated neutrophils in psoriasis.

5-Hydroxytryptamine-stimulated inositol phospholipid hydrolysis in the mouse cortex has pharmacological characteristics compatible with mediation via 5-HT2 receptors but this response does not reflect altered 5-HT2 function after 5,7-dihydroxytryptamine lesioning or repeated antidepressant treatments

5-Hydroxytryptamine (5-HT; 3 x 10(-8)-1 x 10(-5)M) produced a dose-dependent increase in phosphatidylinositol/polyphosphoinositide (PI) turnover in mouse cortical slices, as measured by following production of 3H-labelled inositol phosphates (IPs) in the presence of 10 mM LiCl. Analysis of individual IPs, in slices stimulated for 45 min, indicated substantial increases in inositol monophosphate (IP1; 140%) and inositol bisphosphate (IP2; 95%) contents with smaller increases in inositol trisphosphate (IP3; 51%) and inositol tetrakisphosphate (IP4; 48%) contents. The increase in IP3 level was solely in the 1,3,4-isomer. This response was inhibited by the nonselective 5-HT antagonists methysergide, metergoline, and spiperone. It was also inhibited by the selective 5-HT2 antagonists ketanserin and ritanserin but not by the 5-HT1 antagonists isapirone, (-)-propranolol, or pindolol. 5-HT-stimulated IP formation was also unaltered by atropine, prazosin, and mepyramine. Lesioning brain 5-HT neurones using 5,7-dihydroxytryptamine (5,7-DHT; 50 micrograms i.c.v.) produced a 210% (p less than 0.01) increase in the number of 5-HT2-mediated head-twitches induced by 5-methoxy-N,N-dimethyltryptamine (2 mg/kg). However, 5,7-DHT lesioning had no effect on 5-HT-stimulated PI turnover in these mice. Similarly, an electroconvulsive shock (90 V, 1 s) given five times over a 10-day period caused an 85% (p less than 0.01) increase in head-twitch responses but no change in 5-HT-stimulated PI turnover. Decreasing 5-HT2 function by twice-a-day injection of 5 mg/kg of zimeldine or desipramine (DMI) produced 50% (p less than 0.01) and 56% (p less than 0.01), respectively, reductions in head-twitch behaviour.(ABSTRACT TRUNCATED AT 250 WORDS)

Serotonergic agonists stimulate inositol lipid metabolism in rabbit platelets

The metabolism of inositol phospholipids in response to serotonergic agonists was investigated in rabbit platelets. In platelets prelabelled with [3H]-inositol, in a medium containing 10 mM LiCl which blocks the enzyme inositol-1-phosphatase, 5-hydroxytryptamine (5-HT) caused a dose-dependent accumulation of inositol phosphates (IP). This suggests a phospholipase-C-mediated breakdown of phosphoinositides. Ketanserin, a selective 5-HT2 antagonist, was a potent inhibitor of the 5-HT response, with a Ki of 28 nM, indicating that 5-HT is activating receptors of the 5-HT2 type in the platelet. Lysergic acid diethylamide (LSD) and quipazine also caused dose-related increases in inositol phosphate levels, though these were considerably less than those produced by 5-HT. These results show that relatively small changes in phosphoinositide metabolism induced by serotonergic agonists can be investigated in the rabbit platelet, and this cell may therefore be a useful model for the study of some 5-HT receptors.

A comparison of pulsed ultrasound, radiography and micrometer screw gauge in the measurement of skin thickness

Comparisons of ultrasonic, radiographic and micrometer methods in the measurement of skin thickness were made in 16 volunteers before and after 1-month's treatment with four clobetasol propionate formulations. Correlations between the methods were highly significant (r = 0.68 to 0.75). Correlations in the females were better than in the males suggesting that measurements in women are more easily made. Percentage reductions in skin thickness after steroid treatment were ranked in an identical order, whichever method was used. Each of the three methods, therefore, was shown to be effective. Ultrasound was the preferred technique but the micrometer screw gauge was shown to be a reasonable alternative.

Enhanced release of inflammatory mediators from lithium-stimulated neutrophils in psoriasis

We have used lithium salts to stimulate degranulation in order to assess neutrophil activity in psoriasis. Evidence is presented for significant enhancement of degranulation of beta-glucuronidase (primary granules) and vitamin B12-binding protein (secondary granules) from lithium-stimulated neutrophils in psoriatic whole blood. Basal levels of granule markers showed no significant difference between normal and psoriatic neutrophils. On the other hand, enzymes associated with neutrophil function (myeloperoxidase and catalase) were found to be markedly increased in resting psoriatic neutrophils.

Influence of lithium and fluoride on degranulation from human neutrophils in vitro

We have demonstrated that degranulation from normal human neutrophils in whole blood was stimulated by low concentrations of lithium salts and was produced by noncytolytic means. Significant amounts of beta-glucuronidase could be released from the primary granules, in addition to vitamin B12- binding protein from the secondary granules, by 10 mM lithium. Release was almost totally inhibited by 1 mM fluoride, under the same conditions. There was no release of lactate dehydrogenase and no loss of viability of cells incubated in either lithium or fluoride at the concentrations used. Lithium was also observed to have no effect on reactive oxygen production by phagocytic stimulation of isolated neutrophils. In addition, lithium and fluoride were shown to manipulate the intracellular levels of cAMP. The results demonstrated a direct effect of lithium on release of inflammatory mediators from neutrophils in vitro. The methods used also provide a simple and effective test to study an important function of neutrophil activity and can be used to evaluate degranulation in a number of clinical conditions.

Treatment of chronic plaque psoriasis with dithranol and urea creams: a double-blind study

Stable cream formulations containing 0.1% or 0.2% dithranol in a 17% urea base have been developed. A double-blind comparative trial in 20 out-patients showed that over a 6-week treatment period the 0.2% dithranol and urea cream was significantly more effective (p less than 0.01) than the 0.1% dithranol and urea cream in clearing chronic plaque psoriasis. The 0.2% dithranol/urea cream was accompanied by a higher incidence of minor, irritant side-effects, but was still well accepted by patients for use at home. The availability of differing strengths of dithranol and urea cream enables practitioners to tailor dithranol treatment in accordance with the individual patient's clinical response.

Chattanooga's experience with reorganization for delivery of health services

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