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The ultrastructure of acute silicosis   总被引:2,自引:0,他引:2  
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Analysis of placentas infected with human cytomegalovirus (CMV) suggested that viral transmission could involve differentiating/invasive cytotrophoblasts in villi that attach the placenta to the uterine wall. To parse the cellular components in this process, we developed a coculture system of polarized uterine microvascular endothelial cell (UtMVEC) infection with an endothelial cell-tropic pathogenic strain of CMV. Then we evaluated the potential role of neutrophils and endothelial cells in the spread of infection to differentiating cytotrophoblasts. As shown by immunocytochemistry and analysis of viral replication, CMV preferentially infected endothelial cells via apical membranes and disrupted cell junction proteins, thereby altering paracellular permeability and cell polarity. Neutralizing antibodies to CMV glycoprotein B, an envelope component that facilitates virion penetration, blocked plaque formation in polarized UtMVEC. Neutrophils transmitted CMV infection to UtMVEC, which in turn infected cytotrophoblasts. However, neutrophils did not directly infect cytotrophoblasts. These findings implicate endothelial cells from the uterine microvasculature as a potential source for CMV infection of endovascular cytotrophoblasts of the anchoring villi. Possibly the cytokine/chemokine milieu in the pregnant uterus could attract immune cells that infect endothelial cells in hybrid fetal-maternal vessels. In turn, these cells could infect endovascular cytotrophoblasts, one possible initiation point of a cascade that results in retrograde placental CMV infection.  相似文献   
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Maternal and Child Health Journal - Sleep-related infant deaths in the District of Columbia (DC) varies, with rates in certain geographical areas three times higher than DC and seven times higher...  相似文献   
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This case report illustrates a false-positive result of an I-131 total-body scan caused by abnormal, noncancerous thyroid tissue. A 39-year-old woman underwent an open biopsy and thyroidectomy for a papillary thyroid carcinoma. She was treated by ablation with 150.8 mCi I-131. A follow-up total-body scan revealed a solitary focus of increased activity near the midline at the upper border of the larynx that was subsequently excised. Histologic analysis indicated a fragment of thyroid tissue with chronic inflammation, fibrosis, and squamous metaplasia. No evidence of thyroid carcinoma was present. Hypofunctioning or nonfunctioning residual tissue within the thyroglossal duct may have been suppressed under euthyroid conditions, protecting it from ablation. This tissue may have become stimulated by the high thyroid-stimulating hormone levels, accumulating I-131 and producing a false-positive result of the scan.  相似文献   
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IntroductionTo understand the role of the urinary microbiome in disease states and interpret non-culture-based diagnostic urine testing of midstream urine specimens, we must have a better understanding of the urinary microbiome in asymptomatic, healthy individuals. We examined the impact of gender, age, and menopausal status on the healthy human urinary microbiome in asymptomatic control subjects enrolled in the multi-institution National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Multidisciplinary Approach to the Study of Chronic Pelvic Pain Network (MAPP) study.MethodsAsymptomatic, healthy controls, recruited to be ageand sex-matched to patients in the Trans-MAPP Epidemiology and Phenotyping Study, provided midstream urine collection for polymerase chain reaction (PCR)-electrospray ionization mass spectrometry identification of urinary microbiota. The microbiomes of male and female participants were described and analyzed for differences in composition and diversity at the species and genus level by sex, age, and, in females, by menopausal status.ResultsSixty-six total species were detected with a mean of 1.2 species (standard deviation [SD] 1.1) per male (n=97; mean age=43) and 2.3 (SD 1.3) per female (n=110, mean age=38) in asymptomatic, healthy controls. Species and genera diversity analyses showed significantly greater richness and diversity in females. With regard to species, Bifidobacterium subtile, Lactobacillus crispatus, and Lactobacillus johnsonii were more predominant in females. The genera Bifidobacterium, Staphylococcus, Lactobacillus, and Corynebacterium were more predominant in females, while for males the most prevalent organisms included Staphylococcus and Propionibacterium; only Propionibacterium approached a significant difference between genders. No significant difference in the presence and/or diversity of micro-organisms with menopausal status could be observed. Sex-specific age trends, particularly diversity, were larger for females than males.ConclusionsThese results suggest the urinary microbiome of healthy, asymptomatic subjects differed between genders and age in females, but not menopausal status. Gender differences may be attributable to the detection of urethral/vaginal organisms in females and prostate organisms in males. These findings will better allow us to interpret the results of microbiome reports in the midstream urine specimens of patients with urinary symptoms.  相似文献   
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HIV-infected patients receiving antiretroviral therapy have increased risk of metabolic syndrome, including dyslipidemia. In this study, we determined whether individual nutritional counseling reduced dyslipidemia, particularly low-density lipoprotein (LDL) cholesterol, among HIV-infected patients with dyslipidemia not currently taking lipid-lowering medication. We conducted a randomized 24-week trial among HIV-infected patients with dyslipidemia who were on antiretroviral therapy and were eligible to initiate therapeutic lifestyle changes according to the Thai National Cholesterol Education Program. Participants were randomly assigned to an intervention group that received individual counseling with a nutritionist for seven sessions (baseline, weeks 2, 4, 8, 12, 18, and 24) and a control group that received standard verbal diet information at baseline and nutritional counseling only at week 24. A 24-h recall technique was used to assess dietary intake for both groups at baseline and week 24. Lipid profile (total cholesterol, LDL, high-density lipoprotein (HDL), and triglyceride) was measured at baseline and after 12 and 24 weeks of therapy. An intention-to-treat and linear mixed model were used. Seventy-two patients were randomly assigned, and 62 (86%) participants completed their lipid profile test. After 12 weeks of follow-up, there were significant reductions in the intervention group for total cholesterol (?14.4?±?4.6?mg/dL, P?=?.002), LDL cholesterol (?13.7?±?4.1?mg/dL, P?=?.001), and triglyceride (?30.4?±?13.8?mg/dL, P?=?.03). A significant reduction in LDL cholesterol was also observed in the control group (?7.7?±?3.8?mg/dL, P?=?.04), but there were no significant differences in change of mean lipid levels between the groups at 12 weeks of follow-up. After 24 weeks, participants assigned to the intervention group demonstrated significantly greater decreases in serum total cholesterol (?19.0?±?4.6?vs. 0.2?±?4.3?mg/dL, P?=?.003) and LDL cholesterol (?21.5?±?4.1?vs. ?6.8?±?3.8?mg/dL, P?=?.009). There were no significant changes in HDL cholesterol or triglyceride levels in either group.  相似文献   
10.

Objective

Cardiovascular risk factors in middle-age are associated with cognitive impairment and dementia in older age. Less is known about the burden of calcified subclinical atherosclerosis and cognition, especially in midlife. We examined the association of coronary artery and abdominal aortic calcified plaque (CAC and AAC, respectively) with cognitive functioning in middle-aged adults.

Methods

This cross-sectional study included 2510 black and white adults (age: 43–55 years) without heart disease or stroke who completed a year 25 follow-up exam (2010–11) as part of the Coronary Artery Risk Development in Young Adults Study. CAC and AAC were measured with non-contrast computed tomography. Cognition was assessed with the Digit Symbol Substitution Test (DSST) (psychomotor speed), Stroop Test (executive function), and Rey Auditory Verbal Learning Test (RAVLT) (verbal memory).

Results

A greater amount of CAC and AAC was associated with worse performance on each test of cognitive function after adjustment for age, sex, race, education, and study center. Associations were attenuated, but remained significant for the DSST and RAVLT following additional adjustment for vascular risk factors, including adiposity, smoking, alcohol use, dyslipidemia, hypertension, and diabetes. Compared to participants without CAC or AAC, those with both CAC and AAC, but not CAC or AAC alone was associated with lower DSST scores (p < 0.05).

Conclusions

In this community-based sample, greater subclinical atherosclerotic calcification was associated with worse psychomotor speed and memory in midlife. These findings underscore the importance of a life course approach to the study of cognitive impairment with aging.  相似文献   
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