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BACKGROUND: Studies have shown that alcoholics have smaller brain volumes than non-alcoholic cohorts, but an effect of family history (FH) of heavy drinking on brain volume has not been demonstrated. We examined the relationship between an FH of heavy drinking and both brain shrinkage as measured by the ratio of brain volumes to intracranial volume (ICV) as well as maximal brain growth as measured by ICV in early-onset and late-onset alcoholics. METHODS: With T1-weighted resonance imaging, we measured ICV, brain volume, and white and gray matter volume in adult treatment-seeking late-onset and early-onset alcoholics with either a positive or a negative FH of heavy alcohol use, and in healthy control subjects. We also calculated brain shrinkage using a ratio of soft tissue volumes to ICV. RESULTS: The FH positive alcoholic patients had significantly smaller ICVs than FH negative patients, suggesting smaller premorbid brain growth. Brain shrinkage did not correlate with FH. Late-onset alcoholics showed a greater difference in ICV between FH positive and FH negative patients than early-onset alcoholics. Late-onset FH positive patients also had significantly lower IQ scores than late-onset FH negative patients, and IQ scores were correlated with ICV. CONCLUSIONS: These data provide evidence that parental alcohol use might increase risk for alcoholism in offspring in part by a genetic and/or environmental effect that might be related to reduced brain growth.  相似文献   
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ABSTRACT: Background: The addition of supplementary prenatal support may improve the health and well‐being of high‐risk women and families. The objective of this randomized controlled trial was to examine the impact of supplementary prenatal care on resource use among a community‐based population of pregnant women. Methods: Pregnant women from three urban maternity clinics were randomized (a) to current standard of physician care, (b) to current standard of care plus consultation with a nurse, or (c) to (b) plus consultation with a home visitor. Participants were 1,352 women who received 3 telephone interviews. The primary outcome was resource use (e.g., attended prenatal classes, used nutritional counseling). Results: Overall, those in the nurse intervention group were more likely to attend an “Early Bird” prenatal class and parenting classes, and to use nutrition counseling and agencies that assist with child care. Women provided with extra nursing and home visitation supports were more likely to use a written resource guide, nutrition counseling, and agencies that assist with child care. Among women at higher risk (e.g., language barriers, young maternal age, low income), the nurse intervention significantly increased use of early prenatal classes, whereas the nurse and home visitor intervention significantly increased use of the written resource guide and nutrition counseling. The intervention substantially increased the amount of information received on numerous pregnancy‐related topics but had little impact on resource use for mental health and poverty‐related needs. Among those with added support, resource use among low‐risk women was generally greater than among high‐risk women. Conclusions: Additional support provided by nurses, or nurses and home visitors, can successfully address informational needs and increase the likelihood that women will use existing community‐based resources. This finding was true even for high‐risk women, although this intervention did not reduce the difference in resource use between high‐ and low‐risk women. (BIRTH 33:3 September 2006)  相似文献   
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Rho GTPases have been shown recently to be important for cell polarity and motility of the trunk mesoderm during gastrulation in Xenopus embryos. This work demonstrated that Rho and Rac have both distinct and overlapping roles in regulating cell shape, and the dynamic properties, polarity, and type of protrusive activity of these cells. Overexpression of activated or inhibitory versions of these GTPases also disrupts development of the head in Xenopus embryos. In this study, we have undertaken a detailed analysis of Rho and Rac function in migrating anterior mesendoderm cells. Scanning electron micrographs of these cells in situ revealed that their normal shingle arrangement is disrupted and both the cells and their lamellipodia are disoriented. Anterior mesendoderm explants plated on their natural blastocoel roof matrix, however, still migrated towards the animal pole, although the tendency to move in this direction is reduced compared to controls. Analysis of a number of parameters in time-lapse recordings of dissociated cells indicated that Rho and Rac also have both distinct and overlapping roles in the motility of the prospective head mesoderm; however, their effects differ to those previously seen in the trunk mesoderm. Both GTPases appear to modulate cell polarization, migration, and protrusive activity. Rho alone, however, regulates the retraction of the lagging edge of the cell. We propose that within the gastrulating Xenopus embryo, two types of mesoderm cells that undergo different motilities have distinct responses to Rho GTPases.  相似文献   
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There are limited data on the impact of COVID-19 in children with a kidney transplant (KT). We conducted a prospective cohort study through the Improving Renal Outcomes Collaborative (IROC) to collect clinical outcome data about COVID-19 in pediatric KT patients. Twenty-two IROC centers that care for 2732 patients submitted testing and outcomes data for 281 patients tested for SARS-CoV-2 by PCR. Testing indications included symptoms and/or potential exposures to COVID-19 (N = 134, 47.7%) and/or testing per hospital policy (N = 154, 54.8%). Overall, 24 (8.5%) patients tested positive, of which 15 (63%) were symptomatic. Of the COVID-19-positive patients, 16 were managed as outpatients, six received non-ICU inpatient care and two were admitted to the ICU. There were no episodes of respiratory failure, allograft loss, or death associated with COVID-19. To estimate incidence, subanalysis was performed for 13 centers that care for 1686 patients that submitted all negative and positive COVID-19 results. Of the 229 tested patients at these 13 centers, 10 (5 asymptomatic) patients tested positive, yielding an overall incidence of 0.6% and an incidence among tested patients of 4.4%. Pediatric KT patients in the United States had a low estimated incidence of COVID-19 disease and excellent short-term outcomes.  相似文献   
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A chemically induced syngeneic hamster tumour model of human oral squamous cell carcinoma (OSCC) was used to investigate the possible influence of locally transplanted growing rumours on the immune system of the recipient. Cell activation and cell cytotoxicity assays were performed in vitro using the colorimetric MTT assay to measure any possible changes. The fast growing nature of the tumour model if grafted locally as a fragment was confirmed but not if injected as a single cell suspension (SCS). Stimulation (Concanavalin A) of spleen cells from normal and from tumour bearing animals showed that there was a minor though statistically significant decrease in the mitogenic response of the latter. Thus, the respective stimulatory indices (SI) were 4.06+/-1.61 and 2.06+/-0.87 (0.02

0.01). No significant difference was observed when spleen cells were stimulated with interleukin-2 (IL-2), although there was a similar trend. Pre-immunisation of animals with irradiated autologous SCS three weeks prior to grafting, resulted in a significant decrease in the tumour growth rate of subsequently grafted tumour. Thus, the mean If: SD (weight of takes in mg) for the successful takes of untreated (n=10) and treated (n=9) groups were 52.0+/-52.2 and 25.7+/-19.4 (0.02

0.05) respectively. The number of cases with no tumour takes were 2 of 10 (20%) and 6 of 9 (66%) respectively. In a separate experiment groups of 5 animals were immunized with an increasing number of cells as irradiated SCS, the results of which demonstrated an inverse correlation between the rate of tumour growth and the number of injected tumour cells. The addition of irradiated SCS to IL-2 activated normal spleen cells (LAK cells) in vitro led to a dose-related decrease in the efficiency of cytotoxicity of latter when tested against an xenogeneic super-sensitive surrogate tumour target cell line (Fen cells). Thus, the percent killing by IL-2-activated normal spleen cells was 56.4%. The corresponding mean values for IL-2 activated normal spleen cells in the presence of tumour SCS at 25/1 and 50/1 ratios were 35.9% (p<0.05) and 11.9% (p<0.001) respectively. Ln an attempt to establish the presence of T suppressor cells, spleen cells from tumour bearing animals were injected concomitantly with SCS into 5 recipients. After four weeks no tumour growth had occurred. In conclusion we demonstrated that the presence of injected or grafted tumour had only a minor effect on systemic immune function but induced a strong local anergic effect. This local anergic effect was demonstrable as blocking of LAK activity and thus perhaps allowed suppression of the functional activities of incoming immunocompetent cells.  相似文献   

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PURPOSE: Cyclic 3',5' adenosine monophosphate (cAMP) is a second messenger of the beta adrenergic receptor (betaAR). Ketamine causes an increase in the intracellular accumulation of cAMP in several non-human tissue preparations. A "species effect" may explain the differing results of ketamine on betaAR mediated responses, thus reports of a ketamine-induced increase in cAMP in other species may not be applicable to humans. METHODS: The effect of ketamine (10(-3), 10(-4), or 10(-5) M) pretreatment (60 and 120 min) on isoproterenol [ISO, a beta adrenergic receptor (AR) agonist] or forskolin [FSK, an activator of adenylylcyclase (AC)]-induced intracellular accumulation of cAMP in a human airway smooth muscle (tracheal) cell line (HASM) was evaluated. In an in vitro HASM culture, cells with or without pretreatment were labeled with [3H]adenine to produce [3H]ATP, and following stimulation with ISO or FSK to convert the [3H]ATP to [3H]cAMP, the intracellular accumulation of [3H]cAMP was measured by sequential chromatography over Dowex and alumina columns. RESULTS: Pretreatment of the HASM cells with ketamine (10(-3) and 10(-4) M) caused a reduction (P < 0.05, when compared to untreated cells) in ISO-induced cAMP accumulation, but did not effect cAMP accumulation following FSK stimulation. This effect of ketamine was greater at 120 min of pretreatment than at 60 min (10(-3) M ketamine only)(P < 0.05). No effect was found at either time period following pretreatment of the HASM cells with ketamine 10(-5) M. CONCLUSIONS: These results demonstrate that pretreatment of the HASM cells with ketamine reduces ISO-induced cAMP accumulation. Since only ISO-induced cAMP was effected by ketamine, these data suggest that ketamine inhibits production of cAMP proximal to AC in the cAMP production pathway. These results also demonstrate that a mechanism other than that involving the betaAR and intracellular cAMP accumulation is responsible for the ketamine induced bronchodilation in humans.  相似文献   
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