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41.
42.
The present study aimed to elucidate the distribution of ferric and ferrous iron in the hippocampus after kainate-induced neuronal injury. A modified Perl's or Turnbull's blue histochemical stain was used to demonstrate Fe3+ and Fe2+ respectively. Very light staining for iron was observed in the hippocampus, in normal or saline-injected rats and 1-day post-kainate-injected rats. At 1 week postinjection, a number of Fe3+-positive, but very few Fe2+-positive, cells were present, in the degenerating CA fields. At 1 month postinjection, large numbers of Fe3+-positive glial cells, and some Fe2+-positive blood vessels, were observed. At 2 months postinjection, large numbers of Fe3+- and Fe2+-positive glial cells were present. The labeled cells had light and electron microscopic features of oligodendrocytes, and were double labeled with CNPase, a marker for oligodendrocytes. The observation of an increasing number of Fe3+- and Fe2+-positive cells in the degenerating hippocampus with time is consistent with the results of a nuclear microscopic study, in which an increasing amount of iron was detected in the degenerating hippocampus after kainate injection. In addition, the present study showed a shift in the oxidation state of the accumulated iron, with more cells becoming Fe2+ at a late stage. A possible consequence of the high amounts of Fe2+ in the hippocampus after kainate injection is that it could promote free radical damage in the lesioned areas.  相似文献   
43.
A proximal 15q deletion, del(15) (q11:q13), was detected in a child with Angelman syndrome by cytogenetic analysis of peripheral lymphocytes. The chromosomes of both parents appeared normal. Flow karyotype analysis carried out on lymphoblastoid cell lines derived from the child and her parents confirmed the presence of a de novo 15 deletion. The estimated size of the deleted segment ranged from 6.1-9.5% of chromosome 15 (approximately 6-9.3 million base pairs). The parental origin of the deleted chromosome could not be resolved by flow cytometry, but cytogenetic evidence suggested that it was derived from the smaller chromosome 15 homologue in the mother.  相似文献   
44.
We have studied by immunocytochemistry, the distribution of DMT-1, a cellular iron transporter responsible for transport of metal irons from the plasma membrane to endosomes, in the normal monkey cerebral neocortex and hippocampus. Light to moderate DMT-1 staining was observed in glial cell bodies in the neocortex, the subcortical white matter, and the hippocampus. Despite light labeling of cell bodies, glial end feet around cortical and subcortical blood vessels were heavily labeled. In the neocortex, the glial cell bodies displayed the morphological features of protoplasmic astrocytes. Labeled glial cells in the subcortical white matter contained dense bundles of glial filaments and were identified as fibrous astrocytes. The observation that DMT-1 was present on astrocytic endfeet suggests that these cells are involved in uptake of iron from endothelial cells. It is possible that the iron could then be redistributed into the extracellular space in the brain parenchyma.  相似文献   
45.
A family with five persons affected with fibrodysplasia ossificans progressiva (myositis ossificans progressiva) in three generations is described. This is the first well documented three generation family with this condition and provides further evidence for autosomal dominant inheritance. A wide range of phenotypic severity is apparent, from disabling ectopic bone formation and premature death to an asymptomatic adult with characteristic big toe malformations.  相似文献   
46.
BACKGROUND: Cleft lip with or without cleft palate (CL(P)) and isolated cleft palate (CP) are separate clinical entities and for both polygenic multifactorial aetiology has been proposed. Parents of children with orofacial clefting have been shown to have distinctive differences in their facial shape when compared to matched controls. OBJECTIVE: To test the hypothesis that genetic and morphometric factors predispose to orofacial clefting and that these markers differ for CL(P) and CP. Methods-Polymorphisms at the transforming growth factor alpha (TGFalpha) locus in 83 parents of children with nonsyndromic orofacial clefts were analysed, and their craniofacial morphology was assessed using lateral cephalometry. RESULTS: Parents of children with CL(P) and CP showed an increased frequency of the TGFalpha/TaqI C2 allele (RR=4.10, p=0.009) relative to the comparison group. Also the TGFalpha/BamHI A1 allele was more prevalent in the CP parents. MULTIVARIATE STATISTICAL ANALYSIS: Using stepwise logistic regression analysis the TGFalpha/TaqI C2 polymorphism provides the best model for liability to orofacial clefting. To determine the type of clefting a model involving interaction between the parental TGFalpha/BamHI and TGFalpha/RsaI genotypes showed the best fit. Using genotype only to predict the clefting defect in the children according to parental genotype, 68.3% could be correctly classified. By adding information on craniofacial measurements in the parents, 76% of CP and 94% of CL(P) parents could be correctly classified. CONCLUSIONS: This study provides a model for prediction of liability to orofacial clefting. These findings suggest that different molecular aberrations at the TGFalpha locus may modify the risk for CP and CL(P).  相似文献   
47.
Summary A well characterized strain of guinea pig cytomegalovirus (GPCMV) was used to infect pregnant guinea pigs during various periods of pregnancy. Transplacental transmission of virus with invasion of the fetus was observed, even in some mothers with preinoculation evidence of GPCMV antibody. Fetal infection occurred during the middle third of pregnancy and GPCMV was isolated from many fetal tissues although histologic evidence of infection was not noted. During the last third, abortion of the pregnancy occurred in some animals.This report demonstrates that GPCMV may invade the fetus producing a sublethal, possibly mild infection which may be very similar to the usual type of CMV infection observed in the human newborn.  相似文献   
48.
This short demonstration accomplishes several goals. People see where fat comes from and learn amounts needed to be removed. They practice substituting complex carbohydrate foods for fat. Most important, they learn that changing is not an "all-or-nothing" proposition. They can reduce dietary fat and still eat many of their favorite foods. This demonstration is a useful tool for nutrition educators who want to promote dietary change.  相似文献   
49.
The authors report clinical and histopathologic changes in six patients with symptomatic loiasis. One patient had cutaneous swellings, three patients presented with hydrocele, one patient developed bowel obstruction, and one had generalized fatal loiasis. The first five patients had localized lesions provoked by adult worms; all were surgically removed. The sixth patient died of disseminated loiasis that included a severe loal encephalitis. The authors discuss the mechanism of "Calabar" swellings, the reaction to adult Loa loa worms and loal encephalitis.  相似文献   
50.
While athletes’ nutrient intakes have been widely reported, few studies have assessed the diet quality of athletes. This is the first study to evaluate the diet quality of athletes using the purpose-built Athlete Diet Index (ADI). A convenience sample of 165 elite athletes from Australian sporting institutions completed the ADI online, with subsequent automated results provided to their respective accredited sports dietitians (ASDs). At the completion of athlete participation, ASDs (n = 12) responded to a range of survey items using a Likert scale (i.e., 1 = strongly agree to 5 = strongly disagree) to determine the suitability of the ADI in practice. Differences in ADI scores for demographics and sport-specific variables were investigated using independent t-tests, analysis of variance (ANOVA) and Bonferroni multiple comparisons. Spearman’s rank correlation was used to assess the association between total scores and demographics. The mean total ADI score was 91.4 ± 12.2 (range 53–117, out of a possible 125). While there was no difference in total scores based on demographics or sport-specific variables; team sport athletes scored higher than individual sport athletes (92.7 vs. 88.5, p < 0.05). Athletes training fewer hours (i.e., 0–11 h/week) scored higher on Dietary Habits sub-scores compared with athletes training more hours (≥12 h/week; p < 0.05), suggesting that athletes who train longer may be at risk of a compromised dietary pattern or less than optimal nutrition practices that support training. Most (75%) ASDs surveyed strongly agreed with the perceived utility of the ADI for screening athletes and identifying areas for nutrition support, confirming its suitability for use in practice.  相似文献   
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