Cutaneous larva migrans on the scalp: atypical presentation of a common disease

Cutaneous larva migrans is a pruritic dermatitis due to the inoculation of helminths larvae in the skin, and it often occurs in children in tropical and subtropical areas. The authors describe an atypical case of cutaneous larva migrans in a 11 year-old child with scalp involvement, an unusual topography for this lesion.     

Intermittent resistance exercise and obesity,considered separately or combined,impair spermatic parameters in adult male Wistar rats

Obesity and absence of physical exercise are global problems that affect concentration and sperm quality in the male reproductive system. The purpose of this study was to examine the effect of obesity and resistance training, considered separately or in association, on testicular function and reproductive capacity. Twenty pubertal male Wistar rats were distributed into four groups: control (C) and exercise (E) groups that received standard rat chow; and obese (O) and obese with exercise (OE) groups that received a high‐fat diet. All the groups received filtered water during the experimental conditions. Groups E and OE were submitted to 8 weeks of high‐intensity intermittent training. Afterwards, testes were collected for sperm count, spermatogenic kinetics, histopathology, morphometry and immunodetection of androgen receptors (AR). The vas deferens was collected for sperm morphology. The results showed that obesity increased body weight, naso‐anal length, liver and epididymal fat weight, abnormal spermatozoa and immunodetectable AR. Intermittent exercise decreased daily sperm production (DSP), sperm count and normal spermatozoa, whereas the number of tubules with immunodetectable AR increased. The combination of obesity and intermittent training led to reduced sperm count and DSP, although abnormal spermatozoa and the number of tubules with immunodetectable AR increased. Thus, in conclusion, both obesity and resistance training impaired testicular function during puberty in rats; and this type of exercise has also been shown to be detrimental to testicular physiology.     

Bisphenol A Exposure Impairs Epididymal Development during the Peripubertal Period of Rats: Inflammatory Profile and Tissue Changes

Bisphenol A (BPA) is a synthetic non‐steroidal oestrogen used in the production of plastics. BPA can cause alterations in the endocrine system of human beings and animals at varied stages of development. During puberty, altered morphological, sexual behaviour and completion of the epididymal development occur. Therefore, this study aimed to evaluate the effects of BPA on epididymal development during the peripubertal period of rats. Male Wistar rats were treated with BPA via gavage at doses of 20 μg/kg or 200 μg/kg per day [post‐natal day (PND] 36–66). The control group received the vehicles under the same conditions. Feed and water were provided ad libitum. On PND 67, the epididymis was removed, weighed, divided into caput/corpus and cauda sections. It was then used for sperm count determination; histopathological and stereological evaluation; inflammatory cell enzymatic profiling (myeloperoxidase activity – MPO; N‐acetylglucosaminidase – NAG); immunohistochemistry for IL‐6; and evaluation of superoxide anion levels and malondialdehyde (MDA). Exposure to BPA at 200 μg/kg caused a significant increase of MPO activity and immunoreactivity to IL‐6 (interleukin‐6) as well as remodelling of tissue components in the caput/corpus and cauda regions of the epididymis. Under these experimental conditions, it is concluded that BPA alters post‐natal epididymal development.     

Cholinergic parameters and the retrieval of learned and re-learned spatial information: a study using a model of Wernicke-Korsakoff Syndrome

This is a factorial (2 x 2 x 2) spatial memory and cholinergic parameters study in which the factors are chronic ethanol, thiamine deficiency and naivety in Morris water maze task. Both learning and retention of the spatial version of the water maze were assessed. To assess retrograde retention of spatial information, half of the rats were pre-trained on the maze before the treatment manipulations of pyrithiamine (PT)-induced thiamine deficiency and post-tested after treatment (pre-trained group). The other half of the animals was only trained after treatment to assess anterograde amnesia (post-trained group). Thiamine deficiency, associated to chronic ethanol treatment, had a significant deleterious effect on spatial memory performance of post-trained animals. The biochemical data revealed that chronic ethanol treatment reduced acetylcholinesterase (AChE) activity in the hippocampus while leaving the neocortex unchanged, whereas thiamine deficiency reduced both cortical and hippocampal AChE activity. Regarding basal and stimulated cortical acetylcholine (ACh) release, both chronic ethanol and thiamine deficiency treatments had significant main effects. Significant correlations were found between both cortical and hippocampal AChE activity and behaviour parameters for pre-trained but not for post-trained animals. Also for ACh release, the correlation found was significant only for pre-trained animals. These biochemical parameters were decreased by thiamine deficiency and chronic ethanol treatment, both in pre-trained and post-trained animals. But the correlation with the behavioural parameters was observed only for pre-trained animals, that is, those that were retrained and assessed for retrograde retention.     

Non-fatal occupational injuries: gender and job contract differences

In Brazil, workers without a formal job contract comprise more than half of the labor force, a contingent formed mainly by women. This study presents estimates of the annual incidence of non-fatal work-related injuries and their distribution by gender and type of job contract in an urban area of Brazil. This was a community-based study with a random cluster area sample of the inhabitants from the city of Salvador, capital of the State of Bahia. The study population included all individuals from 18 to 65 years of age who reported having a paid job (n = 2,947). Data were obtained through individual household interviews. The overall estimated annual incidence rate was 5.80%, with a non-statistically significant difference between men (6.05%) and women (5.53%) or workers with (5.67%) and without (5.92%) a formal job contract. These similarities between work-related accidents across gender and type of job contract highlighted the need for greater attention to this problem among women and informal workers, who are largely ignored in official statistics.     

Can vitamins C and E restore the androgen level and hypersensitivity of the vas deferens in hyperglycemic rats?

Diabetic neuropathy can affect the male reproductive system. The aim of this study was therefore to evaluate whether antioxidant (vitamins C and/or E) treatment could attenuate reproductive dysfunctions in hyperglycemic adult male rats. The animals were randomly assigned to one of four experimental groups: hyperglycemic control (Hy), hyperglycemic + 150 mg/day vitamin C (HyC), hyperglycemic + 100 mg/day vitamin E (HyE) or hyperglycemic + vitamins C and E (HyCE). The normoglycemic group (n = 10) received only the vehicles. The testosterone level and noradrenergic response of the vas deferens were analyzed. Both vitamins significantly decreased the TBARS (thiobarbituric acid reactive species) level in the hyperglycemic groups. There was a significant reduction in the testosterone level in the Hy and HyE groups when compared to the normoglycemic group. However, the testosterone levels were partially recovered in the HyC and HyCE groups. In addition, an increased sensitivity of the α-1 adrenoceptor in the vas deferens of the hyperglycemic control group was observed. Treatment with vitamins partially restored (vitamin E or in combination with vitamin C) or totally (vitamin C alone) this dysfunction. Moreover, the maximum response values to norepinephrine were similar among all groups. Thus, we concluded that vitamin C is more efficient than vitamin E in attenuating the effects of hyperglycemia on the male reproductive system of adult rats.     

Reproductive effects in male rats exposed to diuron

Diuron is a ureic herbicide considered to have very low toxicity. The present study evaluated several aspects of reproductive toxicity of diuron in adult male rats. Diuron was diluted in corn oil and administered by oral gavage to groups of 18-20 rats at doses of 0, 125 or 250 mg/kg per day for 30 days; the control group received only the corn oil vehicle. At the end of the treatment period, approximately half the animals from each group were assigned to one of two terminal assessment lines: (1) reproductive organ, liver and kidney weights; measurement of diuron concentrations in liver and kidney; plasma testosterone determinations; evaluation of daily sperm production per testis; sperm number and sperm transit time in the epididymis; or (2) sexual behavior assessment during cohabitation with a receptive female; fertility and pregnancy outcome after natural mating; testicular, epididymal, kidney and liver histopathology; sperm morphology. After 30 days of oral diuron treatment, there were no treatment-related changes in body weights, but dose-related diuron residues were detected in the liver of all treated rats and absolute and relative liver weights were increased in both groups. There were no statistically significant differences between the treated and control groups obtained in plasma testosterone concentrations, or in parameters of daily sperm production, sperm reserves in the epididymis, sperm morphology or measured components of male sexual behavior. On the other hand, the number of fetuses in the litters from diuron-treated rats was slightly smaller than litters from control rats. Therefore, although the results did not indicate that diuron exposure resulted in direct male reproductive toxicity in the rat, they suggest that additional studies should be undertaken to investigate the possible effects on fertility and reproductive performance.     

A probability model for the meiosis I non-disjunction fraction in numerical chromosomal anomalies

Numerical chromosome abnormalities (aneuploidies) are among the most common known causes of mental retardation and the leading cause of pregnancy loss in humans. They primarily arise by the process of meiotic non-disjunction. We still know very little about the contribution of genetic and environmental causes for non-disjunction in humans. In order to increase our understanding of the epidemiology of human trisomies, it is necessary to establish the proportion of cases occurring in the first or second division of meiosis. Trisomic patients will display, in study of microsatellite typed by the polymerase chain reaction (PCR), three fragment peaks of equal intensity, two fragments at an average 2:1 dosage or one individual fragment. In this work we describe a statistical approach for estimation of the fraction of meiosis I non-disjunctions (F) in the absence of the parental information. First we determine a probability model for the number of peaks in a polymorphic microsatellite locus, which is a function of F. Based on this model, we obtain a maximum likelihood estimator for F, using the observed proportion of one, two and three allele patterns in trisomic individuals. Relying on the properties of maximum likelihood theory, we also calculate the asymptotic variance and confidence intervals for F. Owing to the fact that the samples of trisomic patients are limited in number, the use of asymptotic theory may be compromised. Thus, we employ the bootstrap technique to build confidence intervals for F and compare the results with those obtained from the normal theory. This estimator that dispenses the need to study parents opens the possibility of using archival material for comparative epidemiological studies of Down's syndrome and other aneuploidies. In this paper we propose a probability model to estimate the fraction of meiosis I non-disjunction, F, by only using the proportion of allele patterns of trisomy individuals, while traditional methods require typing pericentromeric markers from those affected and their parents.