NADPH-diaphorase Histochemical Labeling Patterns in the Hippocampal Neuropil and Visual Cortical Neurons in Weaned Rats Reared during Lactation on Different Litter Sizes

Abstract

Tissue distribution of nitric oxide-synthases was investigated in the rat hippocampus and visual cortex under nutritional changes induced by modification of the litter size. Young (30-45-days-old) rats, suckled in litters formed by 3, 6 or 12 pups (called small, medium and large litters, respectively), were studied by using nicotine-adenine-dinucleotide phosphate-diaphorase histochemistry (shortly, diaphorase), a simple and robust procedure to characterize tissue distribution of nitric oxide-synthases. We assessed morphometric features of the diaphorase-positive cells in visual cortex, and the neuropil histochemical activity in hippocampal CA1 and dentate gyrus using densitometry analysis. In the large-litter group, the labeled-cell density in white matter of area 17 was higher, as compared to the small-litter group. There was a clear trend, in the large-litter group, to lower values of soma area, dendritic field and branches per neuron, but the differences were not significant. Densitometry analysis of hippocampus revealed a significant increase in the relative neuropil histochemical activity of the dentate gyrus molecular layer in the larger litters, which may be associated to increased compensatory blood flow in the hippocampus. The pathophysiological mechanisms of the observed changes remain to be investigated.     

Suckling in litters with different sizes,and early and late swimming exercise differentially modulates anxiety-like behavior,memory and electrocorticogram potentiation after spreading depression in rats

Objective: Analyze the hypothesis that swimming exercise, in rats suckled under distinct litter sizes, alters behavioral parameters suggestive of anxiety and recognition memory, and the electrocorticogram potentiation that occurs after the excitability-related phenomenon that is known as cortical spreading depression (CSD).

Methods: Male Wistar rats were suckled in litters with six or 12 pups (L₆ and L₁₂ groups). Animals swam at postnatal days (P) 8–23, or P60–P75 (early-exercised or late-exercised groups, respectively), or remained no-exercised. Behavioral tests (open field – OF and object recognition – OR) were conducted between P77 and P80. Between P90 and P120, ECoG was recorded for 2 hours. After this ‘baseline’ recording, CSD was elicited every 30 minutes over the course of 2 hours.

Results: Early swimming enhanced the number of entries and the percentage of time in the OF-center (P?<?0.05). In animals that swam later, this effect occurred in the L6 group only. Compared to the corresponding sedentary groups, OR-test showed a better memory in the L6 early exercised rats, and a worse memory in all other groups (P?<?0.05). In comparison to baseline values, ECoG amplitudes after CSD increased 14–43% for all groups (P?<?0.05). In the L₆ condition, early swimming and late swimming, respectively, reduced and enhanced the magnitude of the post-CSD ECoG potentiation in comparison with the corresponding L₆ no-exercised groups (P?<?0.05).

Discussion: Our data suggest a differential effect of early- and late-exercise on the behavioral and electrophysiological parameters, suggesting an interaction between the age of exercise and the nutritional status during lactation.     

Serine proteases of Leishmania amazonensis as immunomodulatory and disease-aggravating components of the crude LaAg vaccine

We previously demonstrated that intradermal and intramuscular vaccination with Leishmania amazonensis promastigote antigens (LaAg) increases the susceptibility of BALB/c mice to cutaneous leishmaniasis. In this study, we investigated the role played by serine and cysteine proteases as disease-promoting components of LaAg. Mice were immunized by the intramuscular route with LaAg that was pre-treated with a pool of serine or cysteine protease inhibitors (SPi and CPi, respectively) prior to infection with L. amazonensis. Neutralization of either enzyme type reversed the disease-promoting effect of LaAg, as seen by the slower lesion development. However, the parasite burden was only effectively controlled in mice receiving SPi-treated LaAg. Protection was associated with diminished production of TGF-β and particularly IL-10 in response to parasite antigens by the lesion-draining lymph node cells of vaccinated mice relative to control. In vitro, soluble proteases isolated from LaAg (LaSP-Sol) directly activated IL-4, IL-10 and TGF-β production by immune cells. Like native LaAg, vaccination with LaSP-Sol primed mice to respond to parasite challenge with a strong Jones-Mote cutaneous hypersensitivity reaction, and increased susceptibility to infection. Furthermore, neutralization of serine but not cysteine proteases blocked the capacity of LaAg to sensitize mice for Jones-Mote reaction. Together, these results indicate that soluble serine proteases are key components of LaAg responsible for its disease-promoting immunity.     

Alcohol consumption among patients with hepatitis B infection in northern Portugal considering gender and hepatitis B virus genotype differences

Alcohol abuse is an important public health problem. In Portugal with a population of 10 millions of inhabitants, there are around 10% of alcoholics or excessive alcohol drinkers and 1% of chronically infected patients with hepatitis B virus (HBV). To examine the characteristics of patients with higher levels of alcohol consumption and to investigate the association between alcohol consumption and liver damage a total of 298 chronically infected individuals, with HBV genotyped and submitted to liver biopsy, were classified with Child's grading and separated by habits of alcohol intake, less and greater than 20 g/day. No significant differences were observed about genotype but genotypes A and D were predominant in both of them. A higher percentage of males (P < .001) were observed in the group with alcohol intake above 20 g/day, as well a lower proportion of patients with HBeAg negativity (P ≤ .035). In this group, biochemistry parameters, such as alanine aminotransferase (P = .006), aspartate aminotransferase (P = .001), gamma-glutamyl transferase (P < .001) were elevated in a significantly higher proportion than in the other group. The analysis of hematological parameters showed significantly lower values of platelets (P = .042) and mean corpuscular volume (P < .001) and significantly higher values of prothrombin time (P < .001) in the group with higher levels of alcohol consumption. The characteristics of biopsy (P < .001) and Child-Phug's classification (P = .002) revealed more severe results in this group. Logistic regression showed a positive association between liver damage and alcohol intake, increasing with age. In female patients, a strong positive association between alcohol intake and liver damage was also found (odds ratio: 9.379; 95% confidence interval: 0.859-468.422; P = .037); however, the most severe cases were only observed in women older than 45 years. In patients with HBV infection, alcohol is associated with a more severe liver disease. No evidence was found concerning association with HBV genotype.     

Association of parents' nutritional status, and sociodemographic and dietary factors with overweight/obesity in schoolchildren 7 to 14 years old

To assess the association of parents' nutritional status, and dietary and sociodemographic factors with overweight/obesity in schoolchildren in Florianópolis Island, Santa Catarina State, Brazil, this cross-sectional epidemiological study examined 2,826 schoolchildren 7 to 14 years old, classified according to body mass index curves for age and sex recommended by the International Obesity Task Force. Data were analyzed using Poisson regression. The final model showed overweight/obesity in boys associated directly with father's educational level, mother's age, and parents' nutritional status, and inversely with mother's educational level, and number of daily meals. Among girls, it associated directly with parents' nutritional status and the schoolchildren's age, and inversely with consumption of risk foods. The variables that associated with overweight/obesity differed between the sexes, except parents' nutritional status. Boys and girls with both parents overweight or obese were, respectively, 80% and 150% more likely to exhibit the same diagnosis, indicating the need for interventions that include the family environment.     

Antihypertensive,vasodilator and antioxidant effects of a vinifera grape skin extract

Cumulative evidence suggests that moderate wine consumption exerts a cardioprotective effect. We investigated the occurrence of an antihypertensive effect of an alcohol-free hydroalcoholic grape skin extract (GSE) obtained from skins of a vinifera grape (Vitis labrusca) in experimental rodent hypertension models. The vasodilator effect of GSE (polyphenols concentration 55.5 mg g(-1)) was also assessed in the isolated mesenteric vascular bed of Wistar rats and the antioxidant effect was studied on lipid peroxidation of hepatic microsomes. Oral administration of GSE significantly reduced systolic, mean and diastolic arterial pressure in Wistar rats with desoxycorticosterone acetate-salt and N(G)-nitro-L-arginine methyl ester (L-NAME) induced experimental hypertension. In the rat isolated mesenteric vascular bed pre-contracted with norepinephrine, bolus injections of GSE induced endothelium-dependent vasodilatation that was substantially inhibited by L-NAME, but not by indometacin, tetraethylammonium or glibenclamide. Lipid peroxidation of hepatic microsomes estimated as malondialdehyde production was concentration-dependently inhibited by GSE. In conclusion, the antihypertensive effect of GSE might be owing to a combination of vasodilator and antioxidant actions of GSE. These findings also suggest that the beneficial effect of moderate red wine consumption could be owing to an antihypertensive action induced by compounds occurring in the skin of vinifera grapes.     

Vitamin A in prevention of bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) remains one of the most serious challenges in the care of the very preterm infants, affecting approximately one-quarter of infants born < 1500g birth weight and 30% < 1000g. Oxygen toxicity may contribute to its pathogenesis. Vitamin A concentrations are lower in BPD infants which may result in a reduction of the antioxidant protection. It has been found to up regulate genes necessary for fetal lung growth and increase surfactant production in animal models and is also involved in the modulation of immunological and inflammatory responses by regulation of cytokine production. Retinoic acid plays a key role in lung development improving alveolar septation. Evidence exists that vitamin A supplementation for very low birth weight (VLBW) infants, beyond that routinely given in multivitamin preparations, is associated with a reduction in death or BPD. So, parenteral administration of vitamin A to the newborn is one of the current recommended preventive therapies for BPD (number needed to treat 12; 95% CI: 6-94; The information on long-term neurodevelopmental status suggests no evidence of either benefit or harm. Estimates for cerebral palsy range from a number needed to treat of 11 to a number needed to harm of 33. Nowadays, it seems that administration of antenatal vitamin A to the mother in late pregnancy associated with neonatal supplementation can better prevent the development of BPD in areas of endemic vitamin A deficiency. The benefits, in terms of vitamin A status, safety and acceptability of delivering vitamin A in an intravenous emulsion compared with repeat intramuscular injections, the association of vitamin A prenatal and postnatal, as well as the effectiveness and safety of administered high dose vitamin A in ELBW infants await evaluation and should be assessed in further trials.     

Family focus and community orientation in tuberculosis control

This study aimed to describe tuberculosis control actions in the context of Family Health Teams, regarding the dimensions family focus and community orientation. A cross-sectional evaluative research was carried out in 2008, with 84 healthcare workers. The Primary Care Assessment Tool was used, validated and adapted to assess tuberculosis care in Brazil. Respondents answered each question according to a pre-determined scale, (Likert's scale) ranging from zero to five. Data were tabulated using the Statistical Package for the Social Sciences software and were analyzed according to frequency and median. In the first dimension, outcomes revealed that 67.9% of health workers evaluate contact cases with diagnostic tests; 63.1% use radiology tests; 64.3% include the household to face the disease; 77.4% identify risk factors; 41.7% interface with other sectors to find solutions for the identified problems. In the second dimension, 73.8% of them perform case search; 40.5% provide inputs for sputum collection; 50% take educational actions in the community; 14.3% recognize social participation in tuberculosis control. Therefore, the efficiency of such services requires taking actions that give special attention to family and community, and the development of skills to create new spaces for professionals to act and to strengthen the interface with other sectors of society.     

Synthesis and antimalarial activity of thioetherhydroxyethylsulfonamides, potential aspartyl protease inhibitors, Part 3

A series of novel thioetherhydroxyethylsulfonamide derivatives has been synthesized from the coupling of intermediates 3-amino-4-phenyl-1-thioetherazine-butan-2-oles 6,7 with arenesulfonyl chlorides in good yields. Characterizations of products were achieved by NMR techniques and specifically for compound 8e by X-ray crystallography. Preliminary results of antimalarial activity in vitro against the Plasmodium falciparum W2 clone (chloroquine resistant and mefloquine sensitive) showed moderate activity for hydroxyethylsulfonamide 8f. In addition, none of the compounds tested showed cytotoxicity at high concentration tested against HepG2 and BGM cell lines.