Probiotic gut-borne Saccharomyces cerevisiae reduces liver toxicity caused by aflatoxins in weanling piglets

The present study was conducted to investigate the aflatoxin B1 (AFB1) liver toxicity and gut histomorphometry after gut borne-Saccharomyces cerevisiae supplementation to AFB1-contaminated piglet diets. Thirty-two male mixed-breed piglets (weaned at 21 days old) were housed in individual pens and allowed to acclimate for 7 days. Animals were randomly assigned to four treatments of 22 days: T1 – low AFB1 levels diet (L, 31.6 μg/kg); T2 – L + S. cerevisiae 1 g/kg; T3 – high AFs levels diet (H, 495 μg/kg); T4 – H + S. cerevisiae 1 g/kg. The addition of probiotic yeast was able to reduce 72% of residual AFB1 present in the liver. The liver histopathology of piglets fed AFB1 showed a typical macroscopic and microscopic pattern of subclinical aflatoxicosis that was prevented by the yeast. Also, the addition of the yeast was able to decrease the alanine-aminotransferase (25.5±0.71 U) and aspartate-aminotransferase (26.5±6.10 U) even showing values lower than the control ones. The apparent absorption area showed the greater surface when the probiotic was present alone compared to the control (T1), whereas when present together with the toxin demonstrated a modulatory effect. The addition of probiotic gut-borne S. cerevisiae in the pig diets was effective in counteracting the toxic effects of harmful AFB1 in livers besides a tendency to improve the histomorphometric parameters and modulating the toxic effect of AFB1 on intestine. These results are promising for the production of feed additives that will be used in animal feed, since the probiotic action and the decontamination of mycotoxins in the same product are complemented.

Alpha band disruption in the AD-continuum starts in the Subjective Cognitive Decline stage: a MEG study

The consideration of Subjective Cognitive Decline (SCD) as a preclinical stage of AD remains still a matter of debate. Alpha band alterations represent one of the most significant changes in the electrophysiological profile of AD. In particular, AD patients exhibit reduced alpha relative power and frequency. We used alpha band activity measured with MEG to study whether SCD and MCI elders present these electrophysiological changes characteristic of AD, and to determine the evolution of the observed alterations across AD spectrum. The total sample consisted of 131 participants: 39 elders without SCD, 41 elders with SCD and 51 MCI patients. All of them underwent MEG and MRI scans and neuropsychological assessment. SCD and MCI patients exhibited a similar reduction in alpha band activity compared with the no SCD group. However, only MCI patients showed a slowing in their alpha peak frequency compared with both SCD and no SCD. These changes in alpha band were related to worse cognition. Our results suggest that AD-related alterations may start in the SCD stage, with a reduction in alpha relative power. It is later, in the MCI stage, where the slowing of the spectral profile takes place, giving rise to objective deficits in cognitive functioning.

Genetic characterization of Uruguayan Pampa Rocha pigs with microsatellite markers

In this study, we genetically characterized the Uruguayan pig breed Pampa Rocha. Genetic variability was assessed by analyzing a panel of 25 microsatellite markers from a sample of 39 individuals. Pampa Rocha pigs showed high genetic variability with observed and expected heterozygosities of 0.583 and 0.603, respectively. The mean number of alleles was 5.72. Twenty-four markers were polymorphic, with 95.8% of them in Hardy Weinberg equilibrium. The level of endogamy was low (F_IS = 0.0475). A factorial analysis of correspondence was used to assess the genetic differences between Pampa Rocha and other pig breeds; genetic distances were calculated, and a tree was designed to reflect the distance matrix. Individuals were also allocated into clusters. This analysis showed that the Pampa Rocha breed was separated from the other breeds along the first and second axes. The neighbour-joining tree generated by the genetic distances D_A showed clustering of Pampa Rocha with the Meishan breed. The allocation of individuals to clusters showed a clear separation of Pampa Rocha pigs. These results provide insights into the genetic variability of Pampa Rocha pigs and indicate that this breed is a well-defined genetic entity.

Cadmium exposure during pregnancy reduces birth weight and increases maternal and foetal glucocorticoids

Cadmium exposure induces low birth weight through unknown mechanisms. Since low birth weight is associated to foetal exposure to high glucocorticoids (GC) concentrations, we hypothesized that low birth weight induced by prenatal exposure to Cd(2+) is, at least in part, mediated by higher foetal exposure to GC, specifically corticosterone, the main active GC in rodents. Pregnant rats were exposed to different dose of CdCl(2) administered in drinking water during the whole pregnancy period. At term, corticosterone was measured by enzyme immunoassay in maternal and foetal blood and in placental tissues. Cadmium was determined in placentas, maternal tissues (liver and kidney) and foetuses by inductively coupled plasma-mass spectrometry (ICP-MS). Placental 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) activity and expression were determined by a radiometric conversion assay and quantitative RT-PCR respectively. Results demonstrated that 50 ppm of Cd(2+), which was accumulated in different maternal tissues but not in the foetus, reduced pup birth weights and increased plasma corticosterone concentrations, both in mother and foetus. Placental 11beta-HSD2 activity and expression did not change by the treatment. We conclude that 50 ppm of Cd(2+) administered during pregnancy, increase foetal corticosterone concentrations due, probably, to alterations of the regulatory mechanisms of placental barrier to GC causing a mild but significant reduced birth weight.

The quality of reporting of randomized clinical trials published in Ophthalmology

PURPOSE

To evaluate the quality of reporting of all the new randomized clinical trials published during 1999 in OPHTHALMOLOGY: using the CONSORT statement parameters.

DESIGN

Descriptive series of published studies.

STUDIES INCLUDED

Randomized clinical trials.

METHODS

Eligible studies were all randomized clinical trials published in Volume 106 (1999) of OPHTHALMOLOGY: that reported the results of prospectively conducted studies in humans comparing two or more therapeutic options with regard to their effect on one or various outcomes, in which the authors stated that a process of randomization or quasi-randomization was performed before the interventions. Each study was evaluated by two independent observers establishing the specific report in the published manuscript of 57 CONSORT statement descriptors, and consensus was obtained between evaluators.

MAIN OUTCOME MEASURES

Overall presence of CONSORT statement descriptors in published reports.

RESULTS

The mean number of positive CONSORT descriptors for the 24 eligible randomized clinical trials was 33.42 (standard error of the mean [SEM] 1.57) of 57 possible. This score was significantly different (P: < 0.001) from the score of 16.6 (standard error of the mean 0.6) reported for OPHTHALMOLOGY: in the 1991 to 1994 study by Scherer and Crawley. Of the nine descriptors measuring the quality of abstract reporting, a mean of 6.25 (SEM 0.3) was included in the 24 study abstracts evaluated, significantly different from the Scherer and Crawley score (5.2, SEM 0.2. P: < 0.001). Four and six descriptors increased and decreased, respectively, their reporting in more than 20%. Key descriptors such as hypothesis postulation, primary outcome determination, sample size calculations, and a discussion of the limitations of the study such as bias, imprecision, and internal validity are still reported in less than 42% of clinical trials.

CONCLUSIONS

This study describes for the first time after the adoption of the CONSORT statement recommendations the status on the quality of reporting of recently published randomized clinical trials in OPHTHALMOLOGY: Although not a direct measure of the intrinsic quality of a study, reporting quality provides the reader with useful tools for the evaluation of its validity. The quality of reporting of randomized clinical trials shows an overall improvement when compared with the period between 1991 and 1994. However, there is still significant room for improvement, especially in descriptors essential for the validation of clinical trial results that are still widely underreported.

Treadmill exercise-induced stress causes a rise of blood histamine in normotensive but not in primary hypertensive humans

We have previously shown an interaction between noradrenergic and histamine-containing neurons in the rat vas deferens. As a generalized phenomenon, this interaction is involved in a novel peripheral reflex that, in an inhibitory way, modulates sympathetic activity and arterial pressure. Consistent with this, an activation of postganglionic sympathetic neurons causes a rise in rat blood histamine. In the present study, we showed that enhanced sympathetic activity due to treadmill exercise in normotensive humans, is accompanied by a rise in blood histamine, suggesting the presence of a similar neuronal interaction in humans. In contrast, the rise in blood histamine does not occur in primary hypertensive humans during the same degree of physical exercise, suggesting that this interaction is faulty in such hypertensives and could be involved in the pathophysiology of the disease.

[HCV and HBV prevalence in hemodialyzed pediatric patients. Multicenter study]

Hemodialized pediatric patients are a risk population for the hepatitis B and C virus infection. The aim of this paper was to study the serum prevalence of HBV and HCV infection in hemodialized children. We study 61 pediatric patients at hemodialisis, 12 on renal transplant, range between 2 and 20 years old (mean: 12.9 years), 23 male and 38 female. The specific anti-HCV IgC were measured by enzyme immunoassay (ELISA Abbott) and confirmed by LIA-TEK (Organon). The anti-HBV were measured by ELISA Abbott and transaminases by cinetic method (ASAT: 29 UI/L and ALT: 33 UI/L). The 19.7% of studied children were HCV (+) and 29.5% were HBV (+), 38.9% of them were HbsAg (+) and 50% anti-HBs (+). The HCV and HBV infection was more elevated in relation to the transfusion number and the hemodilisis time. The elevation of ALT/ASAT activity isn't a right infection index for HCV and HBV in this children.

Footshock-induced rise of rat blood histamine depends upon the activation of postganglionic sympathetic neurons

We have previously shown the existence of a novel peripheral reflex inhibitorily modulating the vas deferens sympathetic activity. An interaction between noradrenergic and histamine-containing neurons is involved in this reflex. As an overall mechanism of sympathetic autoregulation, we found that enhanced sympathetic activity in the rat during the stress induced by brief inescapable footshocks caused a marked rise of blood histamine that was seemingly dependent upon sympathetic activity. This rise was prevented by either previous ganglionic blockade with hexamethonium or chronic guanethidine-induced sympathectomy. Previous adrenal demedullation did not impair this rise. Thus, it appears that only the sympathetic postganglionic neuron, interacting with a histamine-containing neuron, is involved in the rise of blood histamine induced by footshocks.

Meta-analysis of randomised controlled trials in patients with primary IgA nephropathy (Berger's disease)

An overview of the papers published in the last 10 years was performed to evaluate whether treatment with currently available drugs was beneficial in patients with primary IgA nephropathy (IgAN). Eight selected papers involving 196 IgAN patients with moderate or heavy proteinuria, associated in some cases with the nephrotic syndrome, were analysed. The criteria for inclusion were strict, because meta-analysis requires randomised controlled trials with full descriptions. Furthermore, papers were selected in which treatment was performed on IgAN patients with proteinuria, since prognosis is poor in the presence of this sign. The results of statistical analysis show that IgAN patients with heavy proteinuria, whether or not associated with the nephrotic syndrome, benefit from the administration of corticosteroids and/or cytotoxic drugs, as 66.7% of patients had complete or partial remission both in controlled trials and in retrospective studies; renal function also improved in treated patients. In contrast, no beneficial effect was observed in IgAN patients with moderate proteinuria. These results suggest that it is advisable to administer corticosteroids and/or cytotoxic drugs to IgAN patients with heavy proteinuria, irrespective of the association of this condition with the nephrotic syndrome in individual patients.

Characterization of hemolytic strains of Escherichia coli belonging to classical enteropathogenic O-serogroups

147 isolates of enteropathogenic E. coli (EPEC) belonging to eleven different O-serogroups were examined for hemolysin-synthesis. Hemolysin-producing (Hly+) strains were found at high frequency in O-serogroups 26 and 114 and at low frequency in O-serogroup 126. The hemolytic activities of EPEC strains of different serogroups were found to be low when compared to Hly+ non-EPEC E. coli strains of different origins. Similarities between the hly determinants of EPEC strains and the hly region of an uropathogenic strain were detected by DNA-hybridization. By this method hly genes of EPEC strains belonging to O-serogroups 114 and 126 were localized on the bacterial chromosome. The hly determinants of O26 strains were localized on 100 +/- 5 MD size conjugative plasmids. The hly plasmid pEO5 of the O26 strain C4115 was transferred by conjugation into an E. coli K12 recipient and found to be stable inherited. The hemolytic activity of the transconjugant was comparable to the wildtype O26 donor. The plasmid pEO5 was found to be different in size, compatibility and hemolysin expression from a number of described hemolysin-plasmids.

Monoclonal antibody detection of IncF group plasmid-encoded TraT protein in clinical isolates of Escherichia coli

The TraT protein specified by IncF group plasmids mediates surface exclusion and bacterial resistance to the lethal activities of serum. In this study, an anti-TraT protein monoclonal antibody was generated which failed to react with TraT+ bacteria but which efficiently detected solubilized TraT protein in Western blots and in an enzyme-linked immunosorbent assay. Use of this antibody to screen clinical and nonclinical isolates of Escherichia coli for the production of TraT protein revealed its presence in a modest proportion (38%) of normal fecal strains, a significantly higher proportion of clinical strains (51 to 73%), and an even higher proportion (78 to 88%) of clinical strains concomitantly producing the K1 capsule, an important virulence factor of E. coli.

Mutagenicity obtained experimentally by oral administration of dextroamphetamine sulphate to the rat

Research work on the possible mutagenic effects of the amphetamine, sympathomimetic amine, was carried out on the rat. The method used was the dominant lethal assay, in its sub-acute form. Dextroamphetamine sulphate was administered orally. At the dosage and frequency of the test, dextroamphetamine sulphate was found to be a significantly mutogenic agent. The over-all mutagenic index was 13.92% (P less than 0.01) for the test group and 8.90% for the control group.