984 resultados para Postnatal development


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The pattern of change in shape during postnatal development in skulls of punare (Thrichomys apereoides) skulls, was studied by geometric morphometric techniques. Skull shape observed in T. apereoides varied both with size and age, but variation in size explains most of the overall change in shape. Differences in shape observed among the eight age categories showed that main changes in shape occurred principally between the first and second age categories. Among the other age classes, changes became less pronounced leading to elongation of the snout and the mid-face and narrowing of the basicranium. The change in global shape resulted in lateral compression of the skull. Despite the high level of integration observed, localized transformations dominated the ontogenetic changes in shape indicating the presence of two large scale cranium components-the orofacial and the basicranial region. The ontogenetic pattern in this species seems to follow the same trends observed in the initial phases of development.

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A manufactured product (Ectoplus®) composed by a cypermethrin (44.7%) and dichlorvos (4.2%) mixture was administered (10mg/kg/day, orally, by gavage) to pregnant rats, during the periods of gestation+lactation, gestation, and lactation. Control mothers received vehicle aqueous solution during the gestation+lactation period. With the progeny, in the 1-15 post-natal days (PNDI-15) there were observed alterations in the periods of occurrence of teeth, hair, unfolding of ears, and in the developmental period for following reflexes: postural, palmar grasp, negative geotaxis, and acoustic startle reflex. After weaning (PND21), there were observed the presence of cypermethrin and dichlorvos in the blood brain and liver; decrease in weight of liver, of cholinesterase activity in the plasma, liver, and brain, and hepatic metabolizing activity of drugs; alterations of levels of gamma glutamyl transferase enzymes, of creatinine, and of potassium in the serum of the animals. In conclusion, neonatal exposure to a formulated mixture of cypermethrin and dichlorvos is inductive to alterations in characteristics that indicate somatic and neuromuscular development of the progeny, and in certain biochemical parameters. The results suggest that enzymatic assessment associated with somatic and neuromotor assessment can be important markers of developmental characteristics in neonatal toxicity by pesticide formulations based on mixtures of insecticides.

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Objetive: To provide information for pediatricians and neonatologists to create realistic outcome expectations and thus help plan their actions. Sources of data: Searches were made of the Cochrane Library, MEDLINE, and Lilacs databases. Summary of the findings: The assessment of growth and development over the first 2-3 years must adjust chronological age with respect of the degree of prematurity. There is special concern regarding the prognoses of small for gestational age preterm infants, and for those with bronchopulmonary dysplasia. Attention must be directed towards improving the nutrition of extremely low birth weight infants during their first years of life; these infants have high prevalence levels of failure to catch-up on growth, diseases and rehospitalizations during their first 2 years. They are frequently underweight and shorter than expected during early childhood, but delayed catch-up growth may occur between 8 and 14 years. Extremely low birth weight infants are at increased risk of neurological abnormalities and developmental delays during their first years of life. Educational, psychological, and behavioral problems are frequent during school years. Teenage and adult outcomes show that although some performance differences persist, social integration is not impaired. Conclusions: The growth and neurodevelopment of all ELBW infants must be carefully monitored after discharge, to ensure that children and their families receive adequate support and intervention to optimize prognoses. Copyright © 2005 by Sociedade Brasileira de Pediatria.

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The morphological evolution of the epididymal duct of guinea pigs (Cavia porcellus, L.) was studied on 10, 20, 30, 45, 60, 70, 90 and 100 days of age, being complex, which is due to the proper differentiation postnatal in the epididymal epithelium. Thus, it was observed that the initial segment of the epididymis reveals an increase of epithelial height corresponding to the average height of the main tubular epithelium cells, generally progressive after 45 days of age. The epithelial height in the middle segment were higher in younger stages (10 to 45 days) than in the prepubertal age (60 days), and have a decrease among 70 to 100 days of age. The ductular terminal segment starts a gradual decrease of the epithelial heights from puberal age (70 days), until adult age (90 to 100 days). In addition, this segment showed epithelial waviness that disappeared after 70 days of age, when the lumen fills it with sperm and cellular exfoliation. The cell types of the epididymal tubular epithelium, principal cells, basal cells and apical cells, were observed in all ages. In the epididymis of very young animals, there was a predominance of undifferentiated columnar cells. After 20 days of age, there was natural prevalence of the principal cells on other cell types, what is a feature similar to other mammals.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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ABSTRACT The aim of the present study was to analyze the influence of enriched environment on the distribution of perineuronal nets (PNNs) using a stereogically based unbiased protocol and visual acuity in adult Swiss albino mice that underwent monocular deprivation during the critical period of postnatal development. Eight female Swiss albino mice were monocular deprived were removed and cut at 70 µm thickness in a vibratome and processed for lectin histochemical staining with Wisteria floribunda agglutinin (WFA). Architectonic limits of area 17 were conspicuously defined by WFA histochemical staining, and the optical fractionator stereological method was applied to estimate the total number of PNNs in the supragranular, granular, and infragranular layers. All groups were compared using Student's t-test at a 95% confidence level. Comparative analysis of the average PNN estimations revealed that the EE group had higher PNNs in the supragranular layer (2726.33 ± 405.416, mean ± standard deviation) compared with the SE group (1543.535 ± 260.686; Student's t-test, p = .0495). No differences were found in the other layers. Visual acuity was significantly lower in the SE group (0.55 cycles/degree) than in the EE group (1.06 cycles/degree). Our results suggest that the integrity of the specialized extracellular matrix PNNs of the supragranular layer may be essential for normal visual acuity development.

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O objetivo do presente trabalho e analisar a influencia do enriquecimento ambiental sobre a acuidade visual e a distribuição das redes perineuronais (RPNs) no córtex visual primário de camundongos submetidos a privação monocular durante o período critico pos-natal. Camundongos suíços albinos fêmeas foram submetidos a sutura da pálpebra direita no 10o dia pos-natal (M, n=16), enquanto que os animais do grupo binocular não foram submetidos a nenhum procedimento cirúrgico (B, n=16). Ao completarem 21 dias, os animais foram subdivididos em: ambiente padrão e ambiente enriquecido, constituindo os grupos M.AP, M.AE, B.AP e B.AE. Após três meses, os animais foram submetidos ao teste de acuidade visual, perfundidos e secções coronais de seus cérebros processadas para histoquímica da lectina Wisteria floribunda e posterior quantificação através do método estereologico do fracionador óptico. Os animais do grupo B.AP apresentaram acuidade visual de 0.48 ciclos/grau, enquanto que aqueles alojados em ambiente enriquecido (B.AE) apresentaram um melhor desempenho do teste, atingindo 0.996 ciclos/grau. A acuidade visual foi significantemente menor nos animais submetidos a privação monocular (M.AP 0.18 ciclos/grau; M.AE 0.4 ciclos/grau). Os resultados estereologicos revelaram que o ambiente enriquecido aumenta o numero de RPNs tipo 1 e de RPNs total nas camadas supragranular e granular em ambos os hemisférios nos camundongos submetidos a privação monocular (ANOVA dois critérios, p<0.05), sendo que essa diferença na camada granular e decorrente principalmente do aumento das redes perineuronais da matriz extracelular no hemisfério direito. Na camada infragranular, os animais do grupo M.AE apresentaram um aumento apenas no numero de RPNs tipo 1.

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Aquaporins (AQPs) are membrane protein channels expressed in a wide variety of cells and tissues that are involved in the transport of water. In the male excurrent duct, the movement of fluid and solutes across the epithelium is essential for establishing the proper luminal environment in which sperm mature and are stored. The initial aim of the present propose is to localize AQP 2 e 9 in epithelium of the initial segment, caput, corpus and cauda epididymidis in Mongolian gerbil during postnatal development (10, 30, 60, 120 and 300 days), observing possible changes in the pattern of expression of the AQPs along the postnatal development. The animals will be killed by inhalation of carbon dioxide. After euthanasia, the epididymis will be removed and the different regions will be isolated. The biological material obtained will be processed in accordance with the routines of histological techniques and imunnohistochemistry to study the expression and localization of the AQPs 2 and 9. The results obtained will be analyzed and photographed in conventional light microscope

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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This study investigated whether perinatal exposure to picrotoxin, a GABA(A) antagonist, modifies the effect of muscimol, a GABA(A) agonist, on the sexual behavior of adult male rats. Two hours after birth and then once daily during the next 9 days of lactation, dams received picrotoxin (0.75 mg/kg subcutaneously) or saline (1 ml/kg subcutaneously). The adult male offspring from the picrotoxin and saline groups received saline (1 ml/kg intraperitoneally) or muscimol (1 mg/kg intraperitoneally), and 15 min later, their sexual behavior was assessed. Muscimol treatment in the saline-exposed group increased the mount and intromission latencies. However, these effects were absent in the picrotoxin-exposed groups. The latencies to first ejaculation, postejaculatory mount, and intromission were decreased in both picrotoxin-exposed groups relative to the saline-exposed groups. The picrotoxin + muscimol-treated rats required more intromissions to ejaculate and the picrotoxin-exposed groups made more ejaculations than the saline-exposed groups. Thus, muscimol treatment did not increase the mount and intromission latencies following picrotoxin exposure, but increased the ejaculation frequency, which did not differ between the picrotoxin + muscimol and the picrotoxin + saline groups. These data indicate that perinatal picrotoxin treatment interfered with GABA(A) receptor development Behavioural Pharmacology 23:703-709 (c) 2012 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.

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Rabbits are born blind and deaf and receive unusually limited maternal care. Consequently, their suckling young heavily rely on the olfactory cue for nipple attachment. However, the postnatal morphofunctional adaptations of olfactory mucosa (OM) are not fully elucidated. To clarify on the extent and the pattern of refinement of the OM following birth in the rabbit, morphologic and morphometric analysis of the mucosa were done at neonatal (0-1 days), suckling (2 weeks), weanling (4 weeks), and adult (6-8 months) stages of postnatal development. In all the age groups, the basic components of the OM were present. However, proliferative activity of cells of the mucosal epithelium decreased with increasing age as revealed by Ki-67 immunostaining. Diameters of axon bundles, packing densities of olfactory cells, and cilia numbers per olfactory cell knob increased progressively with age being 5.5, 2.1, and 2.6 times, respectively, in the adult as compared with the neonate. Volume fraction values for the bundles increased by 5.3% from birth to suckling age and by 7.4% from weaning to adulthood and the bundle cores were infiltrated with blood capillaries in all ages except in the adult where such vessels were lacking. The pattern of cilia projection from olfactory cell knobs also showed age-related variations, that is, arose as a tuft from the tips of the knobs in neonates and sucklings and in a radial pattern from the knob bases in weanlings and adults. These morphological changes may be attributed to the high olfactory functional demand associated with postnatal development in the rabbit.

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The role of colostrum and milk in the neonate has been chiefly recognized as a comprehensive nutrient foodstuff. In addition, the provision of colostrum-the first milk-for early immune capacity has been well documented for several species. Colostrum is additionally a rich and concentrated source of various factors that demonstrate biological activity in vitro. Three hypotheses have been proposed for the phenotypic function of these secreted bioactive components: (1) only mammary disposal, (2) mammary cell regulation, and (3) neonatal function [gastrointestinal tract (GIT) or systemic]. Traditionally, it was assumed that the development of the GIT is preprogrammed and not influenced by events occurring in the intestinal lumen. However, a large volume of research has demonstrated that colostrum (or milk-borne) bioactive components can basically contribute to the regulation of GIT growth and differentiation, while their role in postnatal development at physiological concentrations has remained elusive. Much of our current understanding is derived from cell culture and laboratory animals, but experimentation with agriculturally important species is taking place. This chapter provides an overview of work conducted primarily in neonatal calves and secondarily in other species on the effects on neonates of selected peptide endocrine factors (hormones, growth factors, in part cytokines) in colostrum. The primary focus will be on insulin-like growth factors (IGFs) and IGF binding proteins (IGFBPs) and other bioactive peptides, but new interest and concern about steroids (especially estrogens) in milk are considered as well.