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The aim of the present study was investigate, in young rats, the effects of malnutrition on astrocyte distribution of two hypothalamic regions, the circadian pacemaker suprachiasmatic nucleus (SCN) and the medial preoptic area (MPA). Control rats were born from mothers fed on commercial diet since gestation and malnourished rats from mothers fed on multideficient diet, from the beginning of gestation (GLA group) or from the onset of lactation (LA group). After weaning, pups received ad libitum the same diet as their mothers, and were maintained under a 12/12 h light/dark cycle. The animals were analyzed either at 30-33, or 60-63 days of life. Brain coronal sections (50 microm) were processed to visualize glial fibrillary acidic protein (GFAP) immunoreactivity. Compared to control rats, both malnourished groups of 30 and 60 days exhibited a reduced number of GFAP-immunoreactive astrocytes in the SCN. The total GFAP-immunoreactive area in the SCN of the GLA group differed from the control group at both age ranges analyzed. The GFAP expression as measured by the relative optical density (ROD) exhibited a 50-60% reduction in the MPA in both malnourished groups, compared to controls. The results suggest that malnutrition early in life leads to alterations in gliogenesis or glial cell proliferation in both nuclei, being these alterations greater in the MPA. Compensatory plasticity mechanisms in the GFAP-expression seem to be developed in the astrocyte differentiation process in the SCN, especially when the malnutrition is installed from the lactation.  相似文献   
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This study aimed to investigate the effect of a single injection of pilocarpine upon the phenomenon of cortical spreading depression (SD), in adult rats submitted to early malnutrition and/or to REM-sleep deprivation for 72h prior to the SD-recordings. The SD was recorded continuously for 3-4h in 13 well-nourished (W) and 15 early-malnourished (M) adult rats. One to two hours after the beginning of the recording session, a sub-convulsing intraperitoneal (i.p.) injection of pilocarpine (190mg/kg) was applied and its effects on SD were studied during the rest of the recording session. Pilocarpine reduced markedly the ECoG amplitudes in all animals and decreased the SD velocity of propagation in the M-, but not in the W-rats, as compared with the pre-drug values for the same animals. In additional 9W- and 10 M-animals, REM-sleep deprivation was induced during the 72 h preceding the SD-recording session. This condition enhanced the pilocarpine effects on SD in the W-, but not in the M-rats, as compared to the respective non-deprived (ND) groups. The results indicate an important acute cholinergic influence on SD, acting by means of pilocarpine-activated muscarinic receptors. This effect seems to be differentially modulated by sleep deprivation and malnutrition.  相似文献   
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The polymerase chain reaction amplification of a fragment of the B1 gene of Toxoplasma gondii coupled to hybridization was performed in 42 patients from Rio de Janeiro, Brazil. The results showed 50% of positivity in the IgM positive toxoplasmosis group, and 12.5% in the positive IgG and negative IgM individuals. The data presented here revealed a lack of specificity of the molecular approach, clearly indicating that the primers used may co-amplify human sequences.  相似文献   
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The objectives of this study were to determine the percentile levels of the anthropometric indices body mass index (BMI), waist-hip ratio (WHR), and waist circumference (WC) and to verify possible correlations among theses indices in schoolchildren registered at the State Institute of Education, Florianópolis, Santa Catarina State, Brazil. A total of 419 children ages 7 to 9 years were investigated: 215 (51.3%) boys and 204 (48.7%) girls. BMI, WHR, and WC were higher for boys than for girls. However, the differences were only statistically significant for WHR and WC. Prevalence rates were 17.9% for overweight and 6.7% for obesity. The anthropometric indices with the highest correlation were BMI and WC (r = 0.87 and p < 0.01). For overweight, BMI and WC also presented the strongest correlation (r = 0.74). For obesity, WHR and WC showed the best correlation (r = 0.54).  相似文献   
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The effects of prenatal exposure to dichlorvos (DDVP), an organophosphate (OP) pesticide, on pups' physical and neurobehavioral developments were investigated. Forty pregnant rats were treated by gavage with 8.0 mg/kg DDVP or its vehicle (1 ml/kg) from the 6th to the 15th day of pregnancy. At birth, pups were weighed, the litters culled to eight animals (four male and four female), and then observed for physical (pinna detachment, incisor eruption, eye opening, testes descent, and vaginal opening) and neurobehavioral developments (palmar grasp, surface righting, negative geotaxis, and open-field behaviors). As adults, open-field, apomorphine-induced stereotypy, and passive avoidance behaviors were also assessed. Results showed no differences between the body weight of DDVP and control-treated groups. No differences were observed on the measures of physical and neurobehavioral development. Locomotor activity of male pups at 21 days of age was decreased by DDVP exposure. Adult experimental offspring showed a decreased locomotor frequency and an increased immobility duration on open-field behavior in relation to control animals; the apomorphine-induced stereotyped behavior was decreased by the pesticide exposure as well as performance on the passive avoidance task. These data suggest that prenatal DDVP exposure was able to decrease offspring motor function (adolescence and adults) and conditioned response learning, probably by interference with the cholinergic-dopaminergic balance of activity involved with the control of motor function as well as the cholinergic system that modulates learning process.  相似文献   
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Emergency contraception was proven effective nearly 30 years ago yet remains greatly under-utilised. In the Latin American and Caribbean region, it would serve the goals of reducing unwanted pregnancy, unsafe abortion and related morbidity, and as a back-up to condom use and a bridge to longer-term contraceptive methods if made more widely known and available. The International Planned Parenthood Federation Western Hemisphere Region has developed a model for the integration of emergency contraception into sexual and reproductive health care services. This model is being tested in a two-year project with national affiliates in Brazil, Chile, Colombia, the Dominican Republic and Venezuela, and will contribute to the work of the Latin American Consortium for Emergency Contraception. Case studies of Brazil and Colombia describe how health sector reforms, e.g. decentralisation and managed competition among health insurers and service providers, have influenced promotion strategies. The experience of Profamilia Colombia with registration of a dedicated product and providing emergency contraception within its national network of clinics, with a focus on staff training and work with young people, is described. In Brazil, BEMFAM's study of different modalities for offering emergency contraception, e.g. through contractual agreements with municipalities and its own clinics, is highlighted.  相似文献   
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