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81.
Abstract:  We describe a patient with acquired alpha-thalassemia myelodysplastic syndrome (ATMDS). A previously healthy 66-year-old man presented with hemoglobin of 9.3 g/dL, mean corpuscular volume 59 fL, and a bone marrow aspirate with increased erythroid precursors and hypolobulated megakaryocytes. Hemoglobin H inclusions were seen in most red cells after 1% brilliant cresyl blue supravital stain of the peripheral blood. At the molecular level, we identified of a novel mutation in the most 3' exon of the ATRX gene ( C GA→ T GA substitution in codon 2407) resulting in a premature termination codon (p.R2407X). This case provides further evidence for a link between ATRX mutations and ATMDS, and suggests a possible role for the conserved Q-box element in ATRX function.  相似文献   
82.
Tissue-engineered skin substitutes such as Apligraf have emerged over the past 20 years as among the most carefully studied and efficacious of the advanced wound modalities. These products have been proven as effective enhancements to general wound care, promoting wound closure particularly in instances where conventional wound care fails. Marketed for hard-to-heal wounds since 1998, Apligraf has become part of standard wound care in many wound centers across the United States. Despite this situation, few general wound care guidelines incorporate advanced and active wound-healing technologies, such as tissue-engineered skin products. Because of this deficiency, appropriate patient selection and proper use of these product remain largely unaddressed within the general wound care community. Here, we describe the development of guidelines surrounding optimal use of the bilayered living cell therapy, Apligraf, in the treatment of the two types of lower extremity ulcers for which the product is FDA approved: venous leg ulcer and diabetic foot ulcer. The guidelines detailed in this article focus on the identification and selection of patients who are at risk for failure of standard wound care therapy and thus appropriate for Apligraf treatment. The intended audience for these guidelines is the general wound care practitioner, for whom the developed treatment algorithms and accompanying figure legends should provide practical, user-friendly direction simplifying both patient selection and appropriate use of Apligraf within the context of good wound-healing practice.  相似文献   
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ESR2 is expressed in bone cells, yet few studies have tested its variation for association with BMD, an important determinant of osteoporotic fractures. This was investigated in 723 men and 795 women from the Framingham study. Results show association of variation in this gene with BMD in both women and men. INTRODUCTION: Osteoporotic fracture risk is highly dependent on bone density, a quantitative multifactorial trait with a substantial genetic component. In contrast to the growing body of evidence that estrogen receptor alpha (ESR1) plays a role in bone metabolism, few studies have examined the estrogen receptor beta (ESR2) gene for association with BMD. An ESR2 CA repeat polymorphism, D14S1026, was associated with BMD in two small studies, each with <200 women. MATERIALS AND METHODS: The objective of this investigation was to assess whether D14S1026 or four other intronic polymorphisms were associated with BMD in 723 men and 795 women (mean age, 60 years) from the offspring cohort of the population-based Framingham Study. BMD was measured at the femur (neck, trochanter, and Ward's area) and the lumbar spine (L(2)-L(4)). RESULTS: In both women and men, there was significant association of D14S1026 genotype with measures of femoral but not spinal BMD. In addition, genotypes of two common single nucleotide polymorphisms, rs1256031 and rs1256059, in strong linkage disequilibrium with one another but not with D14S1026, were associated with measures of femoral BMD in men. The rs1256031 genotypes had up to a 4.0% difference in mean femoral BMD. An inferred rs1256031-D14S1026-rs1256059 haplotype C-23CA-T was significantly associated with reduced femoral BMD in women (p = 0.03, 0.003, and 0.01 for neck, trochanter, and Ward's area, respectively). Haplotype-based BMD differences ranged from 3.0% to 4.3%. CONCLUSIONS: We have observed significant association of common ESR2 variants with measures of femoral BMD in both men and women.  相似文献   
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OBJECTIVE: To describe the onset of Huntington disease (HD) in a patient with atypical progression of symptoms. BACKGROUND: The authors report the case of a 39-year-old man with severe cognitive impairment and diffuse cortical atrophy before the onset of motor manifestations or symptoms of an extrapyramidal movement disorder. METHOD: Clinical examinations, neuropsychologic assessments, magnetic resonance imaging, electroencephalogram, and genetic testing were conducted. RESULTS AND CONCLUSIONS: Although HD was eventually confirmed through genetic testing, chorea was not part of the clinical picture until well after the patient had developed a frank dementia, with a decline in global intellectual functioning, memory deficits, slowed information processing speed, and executive dysfunction. This case indicates HD may present with atypical clinical features in the early course of the disease, and warrants diagnostic consideration in patients with early dementia of unknown etiology.  相似文献   
88.
Diet and premenopausal bilateral breast cancer: A case-control study   总被引:6,自引:0,他引:6  
We investigated associations between diet and premenopausal bilateral breast cancer in a familial matched case-control study. We studied 140 cases from population-based registries in Los Angeles County (California) and Connecticut, and from the major hospitals in the southern parts of the Province of Quebec. Unaffected sisters of the cases served as matched controls (222 total). Dietary intake were assessed with a food frequency questionnaire. Total fat, monounsaturated fat, polyunsaturated fat, oleic acid, and linoleic acid intake was inversely associated with premenopausal bilateral breast cancer risk. Consumption of carbohydrates (and sweetened beverages) was associated with an increased risk. We observed no associations for dietary fiber, antioxidants, or major food groupings, but we did observe inverse associations for intake of low fat dairy products and tofu. These findings suggest that monounsaturated and polyunsaturated fats, as well as soy foods, might reduce the risk of premenopausal bilateral breast cancer.  相似文献   
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Prevotella intermedia has recently been re-defined and a new species, Prevotella nigrescens has been proposed. However, there is little data available on the incidence of these new species in periodontal health or disease. Black-pigmented anaerobes isolated from diseased and healthy subgingival sites were identified by serotyping, SDS-PAGE and physiological tests. In adult periodontitis subjects, 64% of active sites, 35.7% of inactive sites and 38.5% of healthy sites yielded black-pigmented anaerobes. Of these, Porphyromonas gingivalis was found in 11% of active and 5% of healthy sites in diseased patients, Prevotella intermedia in 15.5% of active and 20.5% of healthy sites, Prevotella nigrescens in 37.7% of active and 11.5% of healthy sites and Prevotella denticola in 3% of active and 1% of healthy sites. In healthy subjects, 50% of sites yielded black-pigmented anaerobes. P. gingivalis was not found in healthy subjects but P. intermedia was found in 18% and P. nigrescens in 31% of sites. SDS-PAGE proved to be a useful method for routinely differentiating P. intermedia and P. nigrescens and two sub-types of the latter species were detected on the basis of band pattern. Only one P. nigrescens sub-type was found in any given individual and one type, typified by ATCC 25261, was more commonly found in deep pockets. However, overall both P. nigrescens and P. intermedia as species were just as frequently found at healthy sites as diseased sites. Thus, these species, in contrast to P. gingivalis , appear to be common commensals but they may act as opportunistic pathogens.  相似文献   
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