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PurposeTo characterize each chromosome’s risk for being involved in embryonic aneuploidy.MethodsThis is a retrospective cohort study conducted at a single, academic center. The cohort consisted of 15,169 consecutive trophectoderm biopsies which then underwent comprehensive chromosome screening utilizing validated real-time polymerase chain reaction (RT-PCR) or single nucleotide polymosphism (SNP) array platforms. Analysis was done to determine probability of aneuploidy by chromosome, changes in that risk with increasing maternal age, and in relationship of aneuploidy to chromosomal structure as classified by prior cytogenetic literature.ResultsThe highest prevalence of imbalances leading to aneuploidy was seen for chromosomes 13, 15, 16, 18, 19, 21, and 22. While elevated in all age groups, there was a disproportionate rise in aneuploidy rates for these chromosomes with increasing maternal age. When classic cytogenetic karyotype groups were compared, the overall smaller groups D, E, and G were associated with the highest rates. Similarly, when grouped based upon structure, acrocentric chromosomes exhibited the highest rates of aneuploidy, followed by the metacentric chromosomes, with the lowest prevalence of error in those with submetacentric structures.ConclusionsThe highest rates of chromosomal aneuploidy were found in chromosomes known to be involved in clinically detectable, abnormal pregnancies, not just simply implantation failure. The rate of aneuploidy in these chromosomes rises disproportionately with age when compared to the other chromosomes which may provide information about chromosomal susceptibility to aging. The biological structure groupings did show varied aneuploidy rates which may provide insight into the biology of aneuploidy.  相似文献   
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Research suggests exercise may reduce eosinophilic airway inflammation in adults with asthma. The Dietary Inflammatory Index (DII®) quantifies the inflammatory potential of the diet and has been associated with asthma outcomes. This study aimed to determine whether the DII of a meal consumed either before or after exercise influences exercise-induced changes in airway inflammation. A total of 56 adults with asthma were randomised to (1) 30–45 min moderate–vigorous exercise, or (2) a control group. Participants consumed self-selected meals, two hours pre- and two hours post-intervention. Energy-adjusted DII (E-DIITM) was determined for each meal, with meals then characterised as “anti-inflammatory” or “pro-inflammatory” according to median DII. Induced sputum cell counts were measured pre- and four hours post-intervention. Participants consuming an anti-inflammatory meal two hours post-exercise had a decrease in sputum %eosinophils (−0.5 (−2.0, 0.3)%) compared with participants who consumed a pro-inflammatory meal two hours post-exercise (0.5 (0, 3.0)%, p = 0.009). There was a positive correlation between the E-DII score of the post-exercise meal and change in sputum %eosinophils (rs = 0.478, p = 0.008). The E-DII score of the meal consumed two hours pre-exercise had no effect on sputum %eosinophils (p = 0.523). This study suggests an anti-inflammatory meal two hours post-exercise augments exercise-induced improvements in eosinophilic airway inflammation in adults with asthma.  相似文献   
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Trosko JE  Upham BL 《Mutagenesis》2005,20(2):81-92
The following is a position paper challenging the paradigm that 'carcinogen = mutagen', and that the current rodent bioassay to predict risks to human cancers is relevant and useful. Specifically, we review current observations concerning carcinogenesis that might lead to another approach for assessing the identification of human carcinogenic hazards and the risk assessment that chemicals might pose. We give a brief review of the multistage and multimechanism process of cancer in a tissue that involves not only genotoxic but also epigenetic events, and the importance of stem and progenitor cells in the development of cancer. We focus on the often ignored 'epigenetic' effects of carcinogens and the role of cell communication systems in epigenetically altering gene expression that leads to an imbalance of cell proliferation, differentiation and apoptosis in a tissue that can contribute to the cancer process. To draw attention to the fact that the current paradigm and policy to test toxic chemicals is often misleading and incorrect, we discuss how oxidative stress, in spite of the DNA damaging data, most probably contributes to cancer at the epigenetic level. Additionally, we briefly review how this mutagenic concept has greatly diverted attention away from doing research on the lower molecular weight, non-genotoxic, polycyclic aromatic hydrocarbons (PAHs), and how these low molecular weight PAHs are etiologically more relevant to the disease potential of environmental mixtures such as cigarette smoke.  相似文献   
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Young mice exposed dermally to the Toximul? (Tox) class of agricultural pesticide adjuvants have reduced levels of hepatic glycogen, a marker of subclinical toxicity. The present study determined whether these effects on glycogen also occurred in cultured HepG2 cells. Exposure (3 hr) to Tox resulted in significant, concentration-dependent glycogen reductions (up to 70%) relative to control values (76 ± 3 μg glycogen/mg protein). These reductions did not appear to be due to loss of cell viability, and were reversible with Tox removal. Two different formulations of Tox (3409F and MP-A) differed significantly in the magnitudes of glycogen reduction in the HepG2 cells.  相似文献   
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This article addresses the needs of families of newborns with congenital heart disease (CHD). Approximately 40,000 infants are born with a congenital heart defect each year; a large percentage survive due to technological advances in treatment, resulting in an increasing number of families who have a child living with a chronic illness. While both parents are significantly affected by a diagnosis of CHD, much of the available literature discusses the experience of mothers. The mother's experiences after learning her child's diagnosis include grief, loss of her imagined healthy child, lack of knowledge of the disease, anger, and difficulty in caregiving, among other issues. Support and encouragement at the time of diagnosis and throughout each stage of the illness are essential. This article describes various strategies that nurses can use to assist these families through their difficult journey.  相似文献   
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Background

In this study, we sought to evaluate the prevalence of metabolic syndrome (MS) in a cohort of pregnant women with a wide range of glucose tolerance, prepregnancy risk factors for MS during pregnancy, and the effects of MS in the outcomes in the mother and in the newborn.

Methods

One hundred and thirty six women with positive screening for gestational diabetes mellitus (GDM) were classified by two diagnostic methods: glycemic profile and 100 g OGTT as normoglycemic, mild gestational hyperglycemic, GDM, and overt GDM. Markers of MS were measured between 2428th during the screening.

Results

The prevalence of MS was: 0%; 20.0%; 23.5% and 36.4% in normoglycemic, mild hyperglycemic, GDM, and overt GDM groups, respectively. Previous history of GDM with or without insulin use, BMI ≥ 25, hypertension, family history of diabetes in first degree relatives, non-Caucasian ethnicity, history of prematurity and polihydramnios were statistically significant prepregnancy predictors for MS in the index pregnancy, that by its turn increased the adverse outcomes in the mother and in the newborn.

Conclusion

The prevalence of MS increases with the worsening of glucose tolerance; impaired glycemic profile identifies pregnancies with important metabolic abnormalities even in the presence of a normal OGTT, in patients that are not classified as having GDM.  相似文献   
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Investigation of pleural effusion: the role of bronchoscopy   总被引:1,自引:0,他引:1  
To assess the place of bronchoscopy in the investigation of pleural effusion, 245 patients presenting during a two year period were reviewed. Of the 46 patients who had bronchoscopy, a positive yield was obtained in 13, though in five of these a second pleural aspiration was also diagnostic. Bronchoscopy was more likely to be diagnostic in patients presenting with a cough (12/24) than in those with no cough (1/22) ( p <0.001), and in those whose chest X-ray revealed significant radiological abnormalities such as hilar enlargement, lung mass or persisting consolidation (12/29), than in those without such changes (1/17) ( p <0.01).
Bronchoscopy has a limited role in the investigation of pleural efision. The presence or absence of cough, and the appearance of the chest X-ray, are both important considerations when planning the investigation of an undiagnosed pleural effusion. (Aust NZ J Med 1992; 22: 41–43)  相似文献   
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