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Background: For many years, biofeedback and neurofeedback have been implemented in the treatment of depression. However, the effectiveness of these techniques on depressive symptomatology is still controversial. Hence, we conducted a meta-analysis of studies extracted from PubMed, Scopus, Web of Science and Embase. Methods: Two different strings were considered for each of the two objectives of the study: A first group comprising studies patients with major depressive disorder (MDD) and a second group including studies targeting depressive symptomatology reduction in other mental or medical conditions. Results: In the first group of studies including patients with MDD, the within-group analyses yielded an effect size of Hedges' g = 0.717, while the between-group analysis an effect size of Hedges' g = 1.050. Moderator analyses indicate that treatment efficacy is only significant when accounting for experimental design, in favor of randomized controlled trials (RCTs) in comparison to non RCTs, whereas the type of neurofeedback, trial design, year of publication, number of sessions, age, sex and quality of study did not influence treatment efficacy. In the second group of studies, a small but significant effect between groups was found (Hedges' g = 0.303) in favor of bio- and neurofeedback against control groups. Moderator analyses revealed that treatment efficacy was not moderated by any of the sociodemographic and clinical variables. Conclusions: Heart rate variability (HRV) biofeedback and neurofeedback are associated with a reduction in self-reported depression. Despite the fact that the field has still a large room for improvement in terms of research quality, the results presented in this study suggests that both modalities may become relevant complementary strategies for the treatment of MDD and depressive symptomatology in the coming years. [ABSTRACT FROM AUTHOR]

A radial pressure profile was incorporated into the HuMPI (Hurricane Maximum Potential Intensity) model that guarantees a direct physical relationship between the calculation of the minimum central pressure and the maximum potential wind speed. The simulations carried out for Hurricanes Matthew and Mar´ıa show that the intensity reached by these systems was approximately 92% of the maximum potential intensity (MPI), while the intensification of Hurricane Michael very close to the southern coast of the United States, reaching an intensity slightly higher than the MPI, evidenced the uncertainties in the knowledge of the physical mechanisms that control the intensification and weakening processes of tropical cyclones, as well as limitations of HuMPI model to estimate the MPI when the sea surface temperature is slightly cold. Furthermore, it was observed that the regions where the study cases reached the maximum intensity coincided with the areas predicted by HuMPI and with regions of the highest sea surface temperature through which the TCs moved. Overall, the results obtained demonstrate the physical consistency of the model to correctly calculate the maximum potential intensity of hurricanes. [ABSTRACT FROM AUTHOR]

A study of the impact of global warming on the intensity of tropical cyclones (TCs) in the North Atlantic (NATL) basin for 2050, 2075 and 2100 was developed, based on the maximum potential intensity (MPI). For this study, the Geophysical Fluid Dynamics Laboratory -- Climate Model (GFDL-CM4) sea surface temperature (SST) outputs and the Hurricane Maximum Potential Intensity (HuMPI) model were used. In the analysis of the mean SST on TCs season, it was observed an increase of 3o C relative to the mean SST of 2017. For 2050, 2075 and 2100 the peak of maximum potential intensity of TCs occurs in June, displaced relative to 2017 where it is observed in July and August. In addition, a continuous increase in the MPI was verified, reaching its extreme values at the end of this century. Thus, for 2100 the maximum potential wind speed exceeds 325 km=h while the potential minimum central pressure is less than 870 hPa. In the Gulf of Mexico, the Caribbean Sea and the Bahamas archipelago area are observed the highest values of potential intensity throughout the TCs season. Monthly, it was observed a similar behavior in all years and lower values are observed in October and November. Likewise, the theoretical intensification rates in 24 hours observed is higher than 380 km=h in 2100, while the mean MPI will be 30% higher at the end of this Century than today. Given the economic and social impact of the TCs, it is necessary to continue studying the impact of climatic change on the intensity and frequency of TCs. [ABSTRACT FROM AUTHOR]

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There has been a growing emphasis on dissemination of empirically supported treatments. Dissemination, however, should not be restricted to treatment. It can and, in the spirit of the scientific-practitioner model, should also involve research. Because it focuses on the investigation of clinical routine as it takes place in local settings and because it can involve the collaboration of several stakeholders, practice-oriented research (POR) can be viewed as an optimal research method to be disseminated. POR has the potential of addressing particularly relevant gaps of knowledge and action when implemented in regions of the world that have limited resources for or experiences with empirical research, and/or in clinical settings that are serving clinical populations who are not typically receiving optimal mental care services - specifically, individuals in rural and inner cities that have limited economic and social resources. The establishment and maintenance of POR in such regions and/or settings, however, come with specific obstacles and challenges. Integrating the experiences acquired from research conducted in various continents (Africa, Europe, Latin America, and North America), the goal of this paper is to describe some of these challenges, strategies that have been implemented to address them, as well as new possible directions to facilitate the creation and growth of POR. It also describes how these challenges and ways to deal with them can provide helpful lessons for already existing POR infrastructures., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

To analyze whether there is improvement in adherence to inhaled treatment in patients with COPD and asthma after an educational intervention based on the teach-to-goal method. This is a prospective, non-randomized, single-group study, with intervention and before-after evaluation. The study population included 120 patients (67 females and 53 males) diagnosed with asthma (70.8%) and COPD (29.1%). The level of adherence (low and optimal) and the noncompliance behavior pattern (erratic, deliberate and unwitting) were determined by the Test of the adherence to Inhalers (TAI). This questionnaire allows you to determine the level of adherence and the types of noncompliance. Low Adherence (LowAd) was defined as a score less than 49 points. All patients received individualized educational inhaler technique intervention (IEITI). Before the IEITI, 67.5% of the patients had LowAd. Following IEITI, on week 24, LowAd was 55% (p = 0.024). Each patient can present one or more types of noncompliance. The most frequent type was forgetting to use the inhaler (erratic), 65.8%. The other types were deliberate: 43.3%, and unwitting: 57.5%. All of them had decreased on the final visit: 51.7% (p = 0.009), 25.8% (p = 0.002), 39.2% (p = 0.002). There were no significant differences in adherence between asthma and COPD patients at the start of the study. The only predicting factor of LowAd was the female gender. An individualized educational intervention, in ambulatory patients with COPD and asthma, in real-world clinical practice conditions, improves adherence to the inhaled treatment., (© 2022. The Author(s).)

Background: In this study, we aimed to investigate the molecular basis of lactation as well as to identify the genetic factors that influence milk yield and composition in goats. To achieve these two goals, we have analyzed how the mRNA profile of the mammary gland changes in seven Murciano-Granadina goats at each of three different time points, i.e. 78 d (T1, early lactation), 216 d (T2, late lactation) and 285 d (T3, dry period) after parturition. Moreover, we have performed a genome-wide association study (GWAS) for seven dairy traits recorded in the 1st lactation of 822 Murciano-Granadina goats., Results: The expression profiles of the mammary gland in the early (T1) and late (T2) lactation were quite similar (42 differentially expressed genes), while strong transcriptomic differences (more than one thousand differentially expressed genes) were observed between the lactating (T1/T2) and non-lactating (T3) mammary glands. A large number of differentially expressed genes were involved in pathways related with the biosynthesis of amino acids, cholesterol, triglycerides and steroids as well as with glycerophospholipid metabolism, adipocytokine signaling, lipid binding, regulation of ion transmembrane transport, calcium ion binding, metalloendopeptidase activity and complement and coagulation cascades. With regard to the second goal of the study, the performance of the GWAS allowed us to detect 24 quantitative trait loci (QTLs), including three genome-wide significant associations: QTL1 (chromosome 2, 130.72-131.01 Mb) for lactose percentage, QTL6 (chromosome 6, 78.90-93.48 Mb) for protein percentage and QTL17 (chromosome 17, 11.20 Mb) for both protein and dry matter percentages. Interestingly, QTL6 shows positional coincidence with the casein genes, which encode 80% of milk proteins., Conclusions: The abrogation of lactation involves dramatic changes in the expression of genes participating in a broad array of physiological processes such as protein, lipid and carbohydrate metabolism, calcium homeostasis, cell death and tissue remodeling, as well as immunity. We also conclude that genetic variation at the casein genes has a major impact on the milk protein content of Murciano-Granadina goats., Competing Interests: Competing interestsThe authors declare that they have no competing interests., (© The Author(s) 2020.)

Background and Objective: We aimed to estimate the prevalence of the Metabolic Syndrome (MS) in rural and urban areas of the Province of Segovia, Spain, according to the ATPIII criteria (National Cholesterol Education Program's Adults Treatment Panel III report) modified., Subjects and Method: Cross-sectional design. Randomized and representative sample of 809 individuals (46% males) aged 35-74 years. Residents in urban and rural areas of the Province of Segovia (Spain). Period of study from January 2000 to January 2003., Results: The age/sex standardized prevalence of the MS was 17%; 15.7% in males and 18.1% in females. No significant differences in MS prevalence between rural and urban areas were found. The most frequent combination of individual components of MS was abdominal obesity, hyperglycemia and arterial hypertension in males and females. MS was associated with age and obesity in an adjusted logistic regression model. In a second model, abdominal obesity was more common in those individuals with a BMI over 30 kg/m2, secondary education level, age over 45 years, and in female residents in rural areas., Conclusions: The sex/age adjusted prevalence was lower than that reported in other studies using the ATPIII criteria in Spain. Abdominal obesity was the most frequent single component of MS in females whereas it was arterial hypertension in males.

Isolated chondrocytes dedifferentiate to a fibroblast-like shape on plastic substrata and proliferate extensively, but rarely form nodules. However, when dissociation is not complete and some cartilage remnants are included in the culture, proliferation decreases and cells grow in a reticular pattern with numerous nodules, which occasionally form small cartilage-like fragments. In an attempt to reproduce this stable chondrogenic state, we added a cartilage protein extract, a sugar extract, and hyaluronan to the medium of previously dedifferentiated chondrocytes. When protein extract was added, many cartilaginous nodules appeared. Hyaluronan produced changes in cell phenotype and behaviour, but not nodule formation. Protein extract has positive effects on the differentiation of previously proliferated chondrocytes and permits nodule formation and the extensive production of type-II collagen. A comparison with incompletely dissociated chondrocyte cultures suggests that the presence of some living cells anchored to their natural extracellular matrix provides some important additional factors for the phenotypical stability of chondrocytes on plastic surfaces. In order to elucidate if it is possible that the incidence of apoptosis is related to the results, we also characterized the molecular traits of apoptosis.

A human B cell clone, EBV-MB91, producing IgMlambda islet cell autoantibody (ICA), obtained by Epstein-Barr virus (EBV) transformation of peripheral CD5- surface Ig+ B cells from a Type 1 diabetic child, and an EBV-MB91-derived hetrohybridoma, HY-MB91, were analyzed for rearranged Ig genes. Both EBV-MB91 and HY-MB91 contained and expressed a unique IgH chain rearrangement (unmutated VH5-51-D6-19-JH5) but contained and expressed two Iglambda chain rearrangements: (i) Vlambda1-4-Jlambda3-Clambda3, which encoded the Iglambda chains (pI, 8.0) of IgMlambda-ICA, showing few mutations but consistent with Ag-driven selection according to the multinomial probability model; and (ii) Vlambda4-1-Jlambda3-Clambda3, with more mutations but inconsistent with antigen-driven selection and involving stop codons that precluded Iglambda synthesis. HY-MB91 showed a progressive loss of IgMlambda-ICA secretion, which was coupled with transcripts of the aberrant Vlambda4-1-Jlambda3-Clambda3 predominating (1.7-fold) over those of Vlambda1-4-Jlambda3-Clambda3. EBV-MB91 also showed the loss of IgMlambda-ICA secretion, associated with cell death. RAG-1 and RAG-2 transcripts occurred in EBV-MB91 but not in HY-MB91, indicating that the former but not the latter might have been able to exhibit V(D)J recombinase activity. Data show that a mature nonmalignant human B cell clone producing IgMlambda-ICA can express RAG-1/RAG-2 transcripts. That the aberrant Vlambda4-1-Jlambda3-Clambda3 was a nonproductive rearrangement occurring at the pre-B cell stage cannot be excluded. However, the hypothetical possibility that one of the two rearrangements corresponded to a secondary rearrangement occurring in the mature B cell represented by the EBV-MB91 clone might also be considered and is discussed.

The purpose of this study was to use a population approach in the preclinical development program of sodium tungstate in the rat in order i) to compute individual pharmacokinetic parameters of this compound after repeated oral administrations, until the 4-week toxicology study, using an empirical Bayes methodology; and ii) to study the influence of the administered dose, of the gender and of the duration of treatment on the pharmacokinetic parameters. Four studies were used representing a mixture of single intravenous administration and multiple oral administrations. The treatment duration ranged from 7 to 28 days. Intravenous dose was 9 mg/kg; three different oral doses were tested, 50, 100 and 200 mg/kg/day. Plasma concentration profiles versus time were compatible with a two-compartment model. A significant gender effect was found on bioavailability. The duration of treatment and the administered dose did not significantly explain part of the interindividual variability of pharmacokinetic parameters. The absorption of tungsten was rapid (1-3 hr). Total plasma clearance and elimination half-life averaged 2.8 ml/min/kg and 3.04 hr in males, and 3 ml/min/kg and 2.74 hr in females. The bioavailability was on an average 70%; being significantly higher in females than in males (0.78 versus 0.61). This compartmental approach should be considered as complementary to the usual non-compartmental approach used for analysis of preclinical data and should be a valuable tool to characterise the pharacokinetic/pharmacodynamic behaviour of a drug.

The aim of this article is to compare total parenteral nutrition (TPN) with oral medium-chain triglycerides-diets (MCT) in the management of spontaneous congenital chylothorax. We analyzed retrospectively the charts of 6 patients seen in our tertiary care center and of 11 comparable patients from the literature. All neonates were symptomatic at birth; 15 had bilateral chylothorax. In the neonates who received mainly TPN (n = 9), the chylothorax resolved significantly (p < 0.05) earlier (mean 10 days, SE 1) than in the others, who received mainly MCT (n = 8) (mean 23 days, SE 4). The mean chyle loss was not significantly different between the 2 groups. Our results suggest that TPN is more effective than oral MCT in the treatment of spontaneous congenital chylothorax. These results support the data of Peitersen et al, who reported that most of the positive results with MCT were achieved in postoperative chylothorax of the newborn.

Leptin, the product of the ob gene, is a recently discovered hormone secreted by adipocytes. Serum leptin concentrations increase in correlation with the percentage of body fat, but besides that little is known about the physiological actions of leptin in humans. The aim of this study was to assess the influence of changes in circulating free-fatty acids on serum leptin levels. Increases in plasma FFA levels (p < 0.02) were obtained in a group of normal subjects following the administration of intralipid plus heparin (250 ml 10% Intralipid plus 5000 U heparin). FFA reduction was achieved through the administration of acipimox (250 mg, orally, at 0 min and at 210 min), a lipid-lowering drug devoid of side effects, to a group of normal (p < 0.02) and obese subjects (p < 0.05). An increase in circulating FFA levels in normal subjects (n = 6), following administration of a lipid-heparin infusion, failed to modify plasma leptin levels as assessed by the area under the curve (AUC; mean +/- SE 892 +/- 168 for placebo vs 896 +/- 260 following intralipid plus heparin). Similarly, whereas acipimox pretreatment induced a reduction in FFA levels compared to placebo in normal (n = 6) and obese subjects (n = 8), it also failed to modify plasma leptin levels at any time-point studied. The results indicate that short-term reduction or increase in circulating FFA are not associated to changes in plasma leptin levels.

The term leishmaniasis covers a series of illnesses caused by the protozoan Leishmania; depending on the patient's immune response, the particular species of the protozoan, and the geography, the condition may manifest itself as cutaneous, mucocutaneous, or visceral disease. Visceral leishmaniasis has often been found as a co-infection associated with the human immunodeficiency virus, particularly in the region of the western Mediterranean. We report the case of an HIV-infected patient with a history of treated laryngeal leishmaniasis who subsequently appeared for treatment with a tumorous lesion on the dorsum of the tongue that was caused by Leishmania infection.

Human islets from an adult subject with nesidioblastosis were isolated and used to perform in vitro studies. Isolated nesidioblastotic islets showed an increased basal rate of insulin secretion (nesidioblastotic islets, 81.3 +/- 6.4 vs. control islets, from cadaveric organ normal donors, 10.2 +/- 0.9 microU/islet/90 min) without any further release with increasing glucose concentration. In addition, islets isolated from the pancreas with nesidioblastosis contained more insulin than control islets, 1,547.0 +/- 128.7 vs. 935.0 +/- 51.7 microU/islet, and the levels of insulin mRNA were also higher than those measured in controls. Interestingly, the serum of the subject with nesidioblastosis contained autoantibodies that stained brightly and selectively a population of islet cells whose distribution coincided with that expected of alpha cells. In summary, pancreatic islets in nesidioblastosis display beta-cell functional abnormalities. Moreover, the finding of antibodies against islet cells is a common feature in the serum of nesidioblastotic subjects; nevertheless, their pathological significance warrants further investigation.

The usefulness of cholinesterase (CS) and cholesterol (CO) in evaluating the nutritional state has been studied, comparing them to two classic parameters: albumin (ALB) and transferrin (TF). The study was done on 73 patients between the ages of 17 and 93, suffering from different afflictions, all of whom were suffering from energy-protein malnutrition (EPM). The patients were divided according to whether the EPM was predominantly visceral (V) or non-visceral (NV), based on the following parameters: ALB, TF, total lymphocytes (TL), cellular immunity test (CIT), triceps skin fold (TSF) and muscular circumference (MC). Our results show significant differences between the V and NV groups for the 4 studied parameters, obtaining lower values for each in the V group. There were significant differences between the ages of both groups, while these did not have any influence on any of the parameters. We found a positive and significant correlation when comparing TF and ALB, TF and CO, TF and CS, CS and ALB, and lastly, CS and CO. There was no correlation between ALB and COO. From our data we concluded that serum cholinesterase is a useful parameter for evaluating the nutritional state of the hospitalized patients.

Aims: The result was assessed of the enteral nutrition guideline prescribed in 50 patients using internationally accepted parameters as indicators of the nutritional state., Methods: Fifty patients were selected at random with an ORL zone neoplasm, they were prescribed enteral nutrition according to our Section's procedure, involving the administration of a commercialized enteral diet whose composition is a homogenization of natural foods administered in 6 sessions at three-hour intervals during the day, begun with 100 cc of diet per session up to a total of 400 (2400 kcal/day), and with the addition of 100 cm of water in each administration. The average age was 59.58 +/- 11.2 years (range 30-81), the average duration of nutrition was 34.02 +/- 32.1 days (range, 3-201 days). The following were taken in all cases: Weight (W), Size (S), Tricipital fold (TF), brachial circumference, urinary creatinin, seric albumin (A), seric transferrin (T), total lymphocytes (Lt) and retarded cutaneous sensitivity, using Multitest IMC (M), and these data were used to calculate muscular circumference (MC) and the creatinin size index (CSI). Two nutritional valuations (NV) were analyzed, the first one taken (NV1) and the one prior to discharge (V2). Analytical calculations were done by our Center's Analytical Laboratory. We used Wilcoxon's test included in the SX statistical package for statistical analysis., Results: On the fifty patients selected, only thirty had a second NV. Comparison of the two calculations gave the following results: A statistically significant rise of A (A1: 3.6 +/- 0.8, vs A: 3.8 +/- 0.7; p < 0.0001) and of T (T1: 208.2 +/- 52.0, vs T2: 237.5 +/- 44.39; p < 0.0001). There was also a statistically significant reduction of P (P1: 63.93 +/- 12.32 vs P2: 62.88 +/- 11.28; p < 0.04). Comparison of the remaining variables did not provide statistically significant differences: PT (PT1: 11.46 +/- 4.9 vs PT2: 12.07 +/- 4.6; p > 0.05). MC (MC1: 23.93 +/- 2.5 vs MC2: 23.58 +/- 1.9; P > 0.05). CSI (CSI1: 8.5 +/- 8 vs CSI2: 6.9 +/- 2.9; p > 0.05). L (L1: 1855 +/- 760.5 vs L2: 1808 +/- 769.1; p > 0.05). M (M1: 12.58 +/- 7.8 vs M2: 14.01 +/- 8.5; p > 0.05)., Conclusions: It is deduced from the results that the guideline used is useful in maintaining the nutritional state of patients prior to their treatment, despite weight-loss, since the ratio of weight-loss to the time between NV1 and NV2 is not significant.

Objective: To assess the degree of compliance with standards defined for Total Parenteral Nutrition (TPN) quality control in our hospital in the two-year period 1991-1992., Material and Methods: All available information was assessed concerning 52 patients (32 men and 17 women) for whom a TPN course was prescribed in relation with certain pre-set indications. These patients received a total of 1140 TPN units with the TPN lasting an average of 21.9 days (range, 1-73 days). Monitoring was done by the Nutrition and Diet Section. The degree of compliance was assessed with the standards model proposed by the Providence Medical Center, Portland (USA) (PMCP) with 24 parameters (PM): indications, initiation in the first 24 hours, nutritional assessment in the first 24 hours, period of the TPN, metabolic complications (14 PM), septic complications (3 PM), nutritional consequences (2 PM) and TPN losses. All parameters were appraised and admitted, except for urea, which was corrected to standard values of our Laboratory (< 44 mg/dl), with Transferrin evaluation instead of iron binding capacity (TIBC), taking as compliance standard a figure of > 190 mg/dl. All analytical calculations were carried out in our Central Laboratory Service., Results: Of all the parameters, the following were discarded, not being calculated on a routine basis: total CO2, serous magnesium, urinary uric nitrogen, nitrogen balance, positive hemocultures, catheters and TPN losses. Levels of compliance varied between 31.9% and 100%, with 8 parameters within the standards (Initiation, 100%; evaluation in first 24 hours, 100%; extent, 100%; creatinine, 100%; total bilirubin, 92.2%; cholesterol, 99.5%; transferrin, 35.9%). Seven parameters fell short (Na, 88.1%; K, 92.9%; Cl, 89.3%; Urea, 54.4%; Glucose, 96.4%; P, 94.1%; Triglycerides, 71.9%)., Conclusions: We infer from our study that there is a need to make use of a large part of the indicators described in the literature as indicators for quality guarantee of a TPN program, and the use of new parameters must be assessed in normal monitoring.

The mechanisms by which interleukin-1 (IL-1) exerts destructive action on the pancreatic islet beta-cells remain elusive. Fragmentation of DNA leading to the activation of poly(ADP-ribose) synthetase was investigated in the present study, by assessing the nuclear response to cytokines in rat pancreatic islets. Nuclear fractions display Mg(2+)-dependent poly(ADP-ribose) synthetase activity catalyzing the incorporation of [adenine-U-14C]NAD, with Ka and Km for Mg2+ and NAD amounting to 0.86 mM and 0.43 mM, respectively. Exposure of the nuclear fraction to rIL-1 beta (10 IU/ml) provoked DNA strand breaks and increased nuclear poly(ADP-ribose) synthetase activity (148.4%, P < 0.01). In intact islets, this nuclear response was observed after 18 h culture in medium containing rIL-1 beta, with a concomitant decrease in NAD (88.5%). Brief periods of pre-incubation (90 min) with rIL-1 beta were unable to induce any nuclear activity. Under these conditions, the presence of IFN-alpha (24 U/ml) and TNF (120 U/ml) was necessary to induce a response to rIL-1 beta. Under the latter experimental conditions, a decrease in NAD content was also observed. The nuclear effects of IL-1 beta were modified by nicotinamide (10 mM), an inhibitor of poly(ADP-ribose) synthetase. It is thus conceivable that an increase in poly(ADP-ribose) synthetase activity together with DNA break is implicated in the beta cytotoxic effect of interleukin-1 beta.

Increased circulating insulin and glucagon levels are a common observation in patients with cirrhosis, as well as in portal hypertensive models. Hyperinsulinemia and hyperglucagonemia may be caused either by increased beta- and alpha-cell secretion or by defective hepatic clearance of these hormones. To elucidate whether an abnormal endocrine pancreatic function might contribute to the hyperinsulinism or to the hyperglucagonism observed in chronic portal hypertension, insulin and glucagon secretion were measured in vitro in isolated pancreatic islets from rats with partial portal vein ligated and rats with cirrhosis caused by carbon tetrachloride poisoning. Both rats with partial portal vein ligation and rats with cirrhosis caused by carbon tetrachloride poisoning exhibited hyperinsulinism and hyperglucagonism as compared with control rats. Isolated pancreatic islets from both experimental portal hypertensive models showed an impaired insulin secretion after glucose stimulation. On the contrary, glucagon secretion was significantly increased, and there was a markedly enhanced response to arginine. This increased in vitro glucagon production could not be corrected, even in the presence of high glucose concentrations in the incubation medium. Therefore our data show that although hyperglucagonism in rats with partial portal vein ligation and in rats with cirrhosis caused by carbon tetrachloride poisoning is promoted by an enhanced alpha-cell secretion, hyperinsulinism is associated with impaired beta-cell secretion.

We studied the revascularization process of isogeneic islets grafted into the kidney subcapsular space of streptozotocin-induced diabetic and nondiabetic rats by a double-labeling, indirect immunofluorescence technique using a rabbit antiserum to human factor VIII-related antigen (which identifies endothelial cells) and a guinea pig anti-insulin antiserum (which labels pancreatic beta cells). Freshly isolated islets contained a network of capillary endothelial cells, whereas 1-week-cultured islets at 37 degrees C have completely lost their intra-islet endothelial cells. Overnight cultured islets contained only occasional endothelial cells. When these islets were grafted under the kidney capsule of nondiabetic rats, they rapidly acquired a new endothelial cell lining as demonstrated by the positivity of staining for factor VIII-related antigen at day 5 after implantation. On the other hand, 1-week-cultured islets failed to become fully revascularized until day 7 after transplantation. Streptozotocin-induced diabetic rats grafted with 1000 islets normalized their blood glucose values (< 11 mM/L) 2-4 weeks after implantation, whereas transplantation of 2500-3000 islets resulted in normoglycemia after 4.7 +/- 2 days (mean +/- SD). Nevertheless, hyperglycemia of the recipient did not adversely affect the process of revascularization of islet isografts which initiated at day 3 and was almost completed by day 5 after implantation.

Alanine aminotransferase has been stabilized by using chemical modification with both bis(imidates) (of varying length) and succinic anhydride. The voltammetric behavior of the native enzyme and its various modified forms has been studied by using both cyclic voltammetry and differential pulse adsorptive voltammetry. A distinctive accumulation pattern was found for each of the stabilized enzymes at the static mercury drop electrode with respect to the native alanine aminotransferase. Adsorptive voltammetry was demonstrated to be a useful technique to assess the extent of chemical modification of this enzyme, which is indirectly related to their stability for use in biotechnological processes. The sue of differential pulse adsorptive voltammetry, after a preconcentration of the enzyme for 300 s at the electrode surface, has yielded a detection limit of 1.0 x 10(-9) M.

A procedure for the isolation of glutamate dehydrogenase (GDH) from human liver, which involves the use of ion-exchange chromatography on diethylaminoethyl cellulose and affinity chromatography on guanosine triphosphate conjugated to Sepharose 4B, is described. The adsorptive voltammetric behaviour of human GDH, bovine GDH and rabbit anti-human GDH antibody was optimised with respect to accumulation potential, accumulation time and scan rate. The lower limits of detection were 0.2 and 1.2 mg l-1 for human and bovine GDH, respectively, and the lower limit of detection for rabbit anti-GDH antibody was 0.04 mg l-1. The interaction of human GDH with rabbit anti-human GDH antibody was also examined using this method.