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971.
The facial nucleus (FN) of the rat is composed of multipolar neurons generated between gestational days G12 and G15. This nucleus is involved in the mechanisms underlying muscle contraction during the sucking reflex. After birth, the neuronal substrate of this reflex is gradually organized to allow the performance of other functions such as gnawing, chewing, swallowing and drinking. Undernourishment is known to produce different degrees of delayed brain development, the greatest of which are similar to the characteristics of the premature syndrome. Neuronal morphological alterations are associated with sucking-reflex deficiencies, which interfere with feeding by the newborn. The current study shows that perinatal undernourishment leads to dendritic arbor hypoplasia and small alterations of soma size in Golgi--Cox impregnated FN neurons of rats. The data suggest that these morphological alterations of FN neurons, may be associated with shifts in the input and integration of signals, and may finally modify the elaboration of motoneuron discharges partly modulating bucolabial muscle contraction during sucking movements and facial expression. Additionally, neonatal nutritional rehabilitation modifies the effects on FN neuronal development, ameliorating the influence of early adverse nutritional conditions.  相似文献   
972.
Using the exogenous cueing task, this study examined whether restrained and disinhibited eaters differ in their orientation of attention towards and their difficulty to disengage from high versus low-fat food pictures in a relatively short (500 ms) and a long presentation format (1500 ms). Overall, participants in the 500 ms condition showed a tendency to direct attention away from high-fat food pictures compared to neutral pictures. No differential pattern was evident for the 1500 ms condition. Correlational analysis revealed that reduced engagement with high-fat food was particularly pronounced for disinhibited eaters. Although in the short term this seems an adaptive strategy, it may eventually become counterproductive, as it could hinder habituation and learning to cope with seductive characteristics of high-fat food.  相似文献   
973.
Activation of endogenous stem cells has been proposed as a novel form of therapy in a variety of neurologic disorders including traumatic brain injury (TBI). Vascular endothelial growth factor (VEGF) is expressed in the brain after TBI and serves as a potent activator of angiogenesis and neurogenesis. In this study, we infused exogenous VEGF into the lateral ventricles of mice for 7 days after TBI using mini-osmotic pumps to evaluate the effects on recovery and functional outcome. The results of our study show that VEGF significantly increases the number of proliferating cells in the subventricular zone and in the perilesion cortex. Fate analysis showed that most newborn cells differentiated into astrocytes and oligodendroglia and only a few cells differentiated into neurons. Functional outcome was significantly better in mice treated with VEGF compared with vehicle-treated animals after TBI. Injury size was significantly smaller at 90 days after TBI in VEGF-treated animals, suggesting additional neuroprotective effects of VEGF. In conclusion, VEGF significantly augments neurogenesis and angiogenesis and reduces lesion volumes after TBI. These changes are associated with significant improvement in recovery rates and functional outcome.  相似文献   
974.
975.
The amphetamine analogue 3,4-methylenedioxymethamphetamine (MDMA or "Ecstasy") is a popular drug of abuse which causes different neurotoxic effects in the mouse compared with the rat. In mice, MDMA produces damage to striatal dopamine terminals, having little long-term effects on serotonin (5-HT) containing neurons. A relevant feature of the striatum is its striosome/matrix compartmental organization; defined by different connexions, and functions. In this study we examined the long-term effect induced by MDMA on tyrosine hydroxylase (TH) and dopamine transporter (DAT) immunoreactivity in the striosomes and matrix compartments of mouse striatum. Mice given MDMA showed significant reductions in TH and DAT immunostaining in striatum compared with control animals. Interestingly, this effect was considerably more pronounced in striosomes than in the matrix. These data provide the first evidence that striosomes and matrix compartments of the mouse striatum have differential vulnerability to MDMA and that the long-term neurotoxicity induced by MDMA in mice is primarily associated with a loss of striosomal dopamine fibres.  相似文献   
976.
977.
The current pandemic SARS-CoV-2 has required an unusual allocation of resources that can negatively impact chronically ill patients and high-complexity procedures. Across the European Reference Network on Pediatric Transplantation (ERN TransplantChild), we conducted a survey to investigate the impact of the COVID-19 outbreak on pediatric transplant activity and healthcare practices in both solid organ transplantation (SOT) and hematopoietic stem cell transplantation (HSCT). The replies of 30 professionals from 18 centers in Europe were collected. Twelve of 18 centers (67%) showed a reduction in their usual transplant activity. Additionally, outpatient visits have been modified and restricted to selected ones, and the use of telemedicine tools has increased. Additionally, a total of 14 COVID-19 pediatric transplanted patients were identified at the time of the survey, including eight transplant recipients and six candidates for transplantation. Only two moderate-severe cases were reported, both in HSCT setting. These survey results demonstrate the limitations in healthcare resources for pediatric transplantation patients during early stages of this pandemic. COVID-19 disease is a major worldwide challenge for the field of pediatric transplantation, where there will be a need for systematic data collection, encouraging regular discussions to address the long-term consequences for pediatric transplantation candidates, recipients, and their families.  相似文献   
978.
979.
Hair growth, a complex process, has long been the subject of intense research. Recent developments in material technology have revealed boehmite as a new therapeutic modality for use in wound healing and scar reduction, indicating its beneficial effects. Nonetheless, the biological bases of the beneficial effects of boehmite remain unknown. We investigated the hair growth properties of boehmite in vitro and in vivo and observed dose-dependent proliferation of human dermal papilla cells (hDPCs) in vitro and hair regrowth in a mouse model. To investigate the effects of boehmite on the promotion of cell transition to the anagen phase, we evaluated hDPC viability, alkaline phosphatase (ALP) activity, protein expression and vascular endothelial growth factor (VEGF) secretion in vitro and assessed the anagen-promoting effects of boehmite via gross observation and histological analysis in a mouse model. Boehmite increased hDPC viability, ALP activity, AKT/GSK3ß/ß-catenin pathway activity, anagen-related gene expression and VEGF secretion; moreover, it accelerated hair regrowth in a catagen-anagen transition model via upregulation of β-catenin signalling and follicular cell proliferation. Collectively, our results indicate that boehmite accelerates hair growth, partly via its effects on critical events in the active phase of the hair follicle cycle, including the promotion of the proliferation of hDPCs and their immediate progeny to the follicle base.  相似文献   
980.
best practice onkologie - Die herkömmliche, von extern applizierte Strahlentherapie mit hochenergetischen Photonen ist fester Bestandteil der Behandlung von Patienten mit intrathorakalen...  相似文献   
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