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51.
Longitudinal data were used to investigate whether anxiety, depressive, disruptive, personality, or substance use disorders are associated with risk for the development of eating disorders during adolescence or early adulthood. Psychiatric disorders were assessed among 726 youths from a random community sample during adolescence and early adulthood. Depressive disorders during early adolescence were associated with elevated risk for the onset of eating disorders, dietary restriction, purging behavior, and recurrent weight fluctuations after preexisting eating problems and other psychiatric disorders were controlled statistically. Disruptive and personality disorders were independently associated with elevated risk for specific eating or weight problems. The present findings suggest that depressive disorders during early adolescence may contribute to the development of eating disorders during middle adolescence or early adulthood.  相似文献   
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Retinoic acid receptor beta (RARB) variants are heavily linked to pathologies of neural crest cell migration. The purpose of this report is to present a 23‐month‐old male with the previously described R387C RARB gain‐of‐function variant whose gastrointestinal issues and long‐term constipation lead to the discovery of colonic hypoganglionosis. This case further delineates the pattern of malformation associated with RARB variants. The findings are also consistent with the known etiology of aganglionic colon due to failed neural crest cell migration.  相似文献   
54.
Adults with Down syndrome (DS) represent a unique population who are in need of clinical guidelines to address their medical care. Many of these conditions are of public health importance with the potential to develop screening recommendations to improve clinical care for this population. Our workgroup previously identified and prioritized co‐occurring medical conditions in adults with DS. In this study, we again performed detailed literature searches on an additional six medical conditions of clinical importance. A series of key questions (KQ) were formulated a priori to guide the literature search strategy. Our KQs focused on disease prevalence, severity, risk‐factors, methodologies for screening/evaluation, impact on morbidity, and potential costs/benefits. The available evidence was extracted, evaluated and graded on quality. The number of participants and the design of clinical studies varied by condition and were often inadequate for answering most of the KQ. Based upon our review, we provide a summary of the findings on hip dysplasia, menopause, acquired cardiac valve disease, type 2 diabetes mellitus, hematologic disorders, and dysphagia. Minimal evidence demonstrates significant gaps in our clinical knowledge that compromises clinical decision‐making and management of these medically complex individuals. The creation of evidence‐based clinical guidance for this population will not be possible until these gaps are addressed.  相似文献   
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To optimize fitness under conditions of varying Darwinian opportunity, organisms demonstrate tremendous plasticity in their life-history strategies based on their perception of available resources. Higher-energy environments generally promote more aggressive life-history strategies, such as faster growth, larger adult size, greater genetic variation, shorter lifespan, larger brood sizes, and offspring ratio skewed towards the larger-sized gender. While numerous mechanisms regulate life-history plasticity including genetic imprinting, methylation, and growth factors, evidence suggests that thyroid hormone plays a central role. Given the pivotal adaptive role of thyroid hormone, the teleology of its dependence on dietary iodine for production remains unexplained. We hypothesize that iodine may have emerged as a substrate for production of thyroid hormone in prehistoric ecosystems because the former represented a reliable proxy for ecologic potential that enabled the latter to modulate growth, reproduction, metabolic rate, and lifespan. Such a scenario may have existed in early marine ecosystems where ocean-surface vegetation, which concentrates iodine for its antimicrobial and antioxidant properties, formed the basis of the food chain. Teleologic parallels can be drawn to the food-chain accumulation of antimicrobials that also exhibit antioxidant properties and promote adult size, brood size, and offspring quality by modulating central hormonal axes. As each higher species in the food chain tunes its life-history strategy based on iodine intake, the coupling of this functional role of iodine with its value as a resource signal to the next member of the food-chain may promote runaway evolution. Whereas predators in prehistoric ecosystems successfully tuned their life-history strategy using iodine as a major input, the strategy may prove maladaptive in modern humans for whom the pattern of iodine intake is decoupled from resource availability. Iodine acquired through sodium iodide supplementation may independently contribute to some biologic dysfunctions currently attributed to sodium.  相似文献   
57.
Gene expression of connective tissue growth factor in adult mouse   总被引:6,自引:0,他引:6  
The connective tissue growth factor (CTGF) is a well-known fibroblast mitogen and angiogenic factor that plays an important role in bone formation during embryogenesis. In the adult, CTGF is involved in wound healing as well as fibrotic and vascular disease. However, little is known about its physiological functions under non-pathological conditions in the adult organism. Here, we describe the cellular site of the CTGF mRNA expression in adult male and female mice as revealed by in situ hybridization histochemistry. Strong and persistent CTGF gene expression was particularly prominent in the mesenchyme of the cardiovascular system (aorta, auricular tissue, renal glomeruli), the mesenchyme surrounding the ovarian follicles or the testicular tubes in the gonadal tissue, and the subcapsular mesenchyme bordering densely innervated parts of whisker hair vibrissae. CTGF hybridization signals were not observed in the mesenchyme of many other organs including gut, muscle, liver or most parts of the lymphatic tissue. Strong expression was also present in the primary (early) ovarian follicles, the epithelium of the deep uterine glands and on myenteric ganglia neurons. These data suggest a selective and continuous mesenchymal function in the gonads and those tissues attracting very strong vascular supply or peripheral innervation. CTGF may also be involved in the cyclical proliferation of the uterine gland epithelium and in the early stages of follicular maturation, as well as in the neuropeptide regulation in the gut, cardiovascular and renal systems.  相似文献   
58.
Several dimorphic fungi are important human pathogens, but the origin and maintenance of virulence in these organisms is enigmatic, since an interaction with a mammalian host is not a requisite for fungal survival. Recently, Cryptococcus neoformans was shown to interact with macrophages, slime molds, and amoebae in a similar manner, suggesting that fungal pathogenic strategies may arise from environmental interactions with phagocytic microorganisms. In this study, we examined the interactions of three dimorphic fungi with the soil amoeba Acanthameobae castellanii. Yeast forms of Blastomyces dermatitidis, Sporothrix schenckii, and Histoplasma capsulatum were each ingested by amoebae and macrophages, and phagocytosis of yeast cells resulted in amoeba death and fungal growth. H. capsulatum conidia were also cytotoxic to amoebae. For each fungal species, exposure of yeast cells to amoebae resulted in an increase in hyphal cells. Exposure of an avirulent laboratory strain of H. capsulatum to A. castellanii selected for, or induced, a phenotype of H. capsulatum that caused a persistent murine lung infection. These results are consistent with the view that soil amoebae may contribute to the selection and maintenance of certain traits in pathogenic dimorphic fungi that confer on these microbes the capacity for virulence in mammals.  相似文献   
59.
PURPOSE: Primary care physicians are an important source of information on weight management. Nevertheless, weight loss counseling by these physicians remains inadequate. This study sought to determine physicians' barriers to providing weight loss counseling in a public hospital, patients' recall of physicians' weight loss recommendations, and the influence of physicians' counseling on patients' understanding, motivation, and behavior regarding weight loss. METHOD: In 2001, four focus groups of faculty and residents were held at two primary care clinics affiliated with the Louisiana State University Health Sciences Center-Shreveport to determine the barriers to providing weight loss counseling. Scripted probes were used to uncover consensus norms. In 2001-02, structured exit interviews were conducted with 210 overweight or obese patients recruited from the clinics to determine patients' recall of physicians' weight loss recommendations, and patients' understanding of the relationship between weight and health, and their stages of readiness for weight loss. RESULTS: Physicians identified major barriers to providing weight loss counseling, including insufficient confidence, knowledge, and skills. Obesity was underdocumented as a distinct clinical diagnosis. Only 5% of the patients recalled being given the combined weight loss strategy of diet and exercise. However, patients who recalled being counseled to lose weight were more likely to understand the risks of obesity, the benefits of weight loss, and were at a higher stage of readiness for weight loss. CONCLUSIONS: Physicians' weight loss counseling had a significant effect on patients' understanding of and motivation for weight loss. However, physicians provided insufficient guidance on weight management strategies, possibly because of inadequate counseling skills and confidence.  相似文献   
60.
Genetic testing was completed on 1,294 persons with deafness referred to the Molecular Otolaryngology Research Laboratories to establish a diagnosis of DFNB1. Exon 2 of GJB2 was screened for coding sequence allele variants by denaturing high-performance liquid chromatography (DHPLC) complemented by bidirectional sequencing. If two deafness-causing mutations of GJB2 (encoding Connexin 26) were identified, further screening was not performed. If only a single deafness-causing mutation was identified, we screened for the g.1777179_2085947del (hereafter called del(GJB6-D13S1830); GenBank NT_024524.13) and mutations in the noncoding region of GJB2. Phenotype-genotype correlations were evaluated by categorizing mutations as either protein truncating or nontruncating. A total of 205 persons carried two GJB2 exon 2 mutations and were diagnosed as having DFNB1; 100 persons carried only a single deafness-causing allele variant of exon 2. A total of 37 of these persons were c.35delG carriers, and 51 carried other allele variants of GJB2. Persons diagnosed with DFNB1 segregating two truncating/nonsense mutations had a more severe phenotype than persons carrying two missense mutations, with mean hearing impairments being 88 and 37%, respectively (P < 0.05). The number of deaf c.35delG carriers was greater than expected when compared to the c.35delG carrier frequency in normal-hearing controls (P < 0.05), suggesting the existence of at least one other mutation outside the GJB2 coding region that does not complement GJB2 deafness-causing allele variants.  相似文献   
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