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With increasing rates of obesity and new diagnostic criteria for gestational diabetes mellitus (GDM), the overall prevalence of GDM is increasing worldwide. Women with GDM have an increased risk of maternal and fetal complications during pregnancy as well as long-term risks including higher prevalence of type 2 diabetes mellitus and cardiovascular disease. In recent years, the role of immune activation and inflammation in the pathogenesis of GDM has gained increasing attention. This monograph explores the current state of the literature as regards the expression of markers of inflammation in the maternal circulation, placenta, and adipose tissue of women with GDM. 相似文献
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Barbara S. Shane Errol Zeiger Walter W. Piegorsch Ewan D. Booth Jay I. Goodman Richard C. Peffer 《Environmental and molecular mutagenesis》2012,53(1):1-9
Propiconazole (PPZ) is a conazole fungicide that is not mutagenic, clastogenic, or DNA damaging in standard in vitro and in vivo genetic toxicity tests for gene mutations, chromosome aberrations, DNA damage, and cell transformation. However, it was demonstrated to be a male mouse liver carcinogen when administered in food for 24 months only at a concentration of 2,500 ppm that exceeded the maximum tolerated dose based on increased mortality, decreased body weight gain, and the presence of liver necrosis. PPZ was subsequently tested for mutagenicity in the Big Blue® transgenic mouse assay at the 2,500 ppm dose, and the result was reported as positive by Ross et al. ([2009]: Mutagenesis 24:149‐152). Subsets of the mutants from the control and PPZ‐exposed groups were sequenced to determine the mutation spectra and a multivariate clustering analysis method purportedly substantiated the increase in mutant frequency with PPZ (Ross and Leavitt. [2010]: Mutagenesis 25:231‐234). However, as reported here, the results of the analysis of the mutation spectra using a conventional method indicated no treatment‐related differences in the spectra. In this article, we re‐examine the Big Blue® mouse findings with PPZ and conclude that the compound does not act as a mutagen in vivo. © Environ. Mol. Mutagen. 2012. Published 2011 Wiley Periodicals, Inc. 相似文献
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The growth factor heregulin (HRG) promotes breast cancer (BC) tumorigenesis and metastasis and differentially modulates BC cell responses to DNA-damaging agents via its dual extracellular and nuclear localization. Given the central role of telomere dysfunction to drive carcinogenesis and to alter the chemotherapeutic profile of transformed cells, we hypothesized that an unanticipated nuclear function of HRG might be to regulate telomere length. Engineered overexpression of the HRGβ2 isoform in non-aggressive, HRG-negative MCF-7 BC cells resulted in a significant shortening of telomeres (up to 1.3 kb) as measured by Southern blotting of telomere terminal restriction fragments. Conversely, antisense-mediated suppression of HRGβ2 in highly aggressive, HRG-overexpressing MDA-MB-231 and Hs578T cells increased telomere length up to 3.0 kb. HRGβ2 overexpression promoted a marked upregulation of telomere-binding protein 2 (TRF2) protein expression, whereas its knockdown profoundly decreased TRF2 expression. Double staining of endogenous HRGβ2 with telomere-specific peptide nucleic acid probe/fluorescence in situ hybridization (PNA/FISH) revealed the partial localization of HRG at the chromosome ends. Moreover, a predominantly nucleoplasmic staining pattern of endogenous HRGβ2 appeared to co-localize with TRF2 and, concomitantly with RAP1, a telomere regulator that specifically interacts with TRF2. Small interfering RNA-mediated knockdown of HRG decreased the expression of TRF2 and RAP1, decreased their presence at chromosome ends, and coincidentally resulted in the formation of longer telomeres. This study uncovers a new function for HRGβ2 in controlling telomere length, in part due to its ability to regulate and interact with the telomere-associated proteins TRF2 and RAP1. 相似文献
36.
Naniche D Lahuerta M Bardaji A Sigauque B Romagosa C Berenguera A Mandomando I David C Sanz S Aponte J Ordi J Alonso P Menendez C 《HIV medicine》2008,9(9):757-764
Objectives
Malaria infection may impact on mother‐to‐child transmission (MTCT) of HIV‐1. Prevention of malaria in pregnancy could thus potentially affect MTCT of HIV. We studied the impact of intermittent preventive treatment during pregnancy (IPTp) on HIV‐1 MTCT in southern Mozambique.Methods
A total of 207 HIV‐positive Mozambican pregnant women were enrolled in the study as part of a randomized placebo‐controlled trial of two‐dose sulfadoxine‐pyrimethamine (SP) IPTp in women receiving single‐dose nevirapine to prevent MTCT of HIV. HIV RNA viral load, maternal anaemia and peripheral and placental malaria were assessed at delivery. Infant HIV status was determined by DNA polymerase chain reaction (PCR) at 1 month of age.Results
There were 19 transmissions of HIV in 153 mother–infant pairs. IPTp with SP did not have a significant impact on MTCT (11.8% in the SP group vs. 13.2% in the placebo group; P=0.784) or on maternal HIV RNA viral load [16 312 (interquartile range {IQR} 4076–69 296) HIV‐1 RNA copies/mL in the SP group vs. 18 274 (IQR 5471–74 104) copies/mL in the placebo group; P=0.715]. In multivariate analysis, maternal HIV RNA viral load [adjusted odds ratio (AOR) 19.9; 95% confidence interval (CI) 2.3–172; P=0.006] and anaemia (haematocrit <33%; AOR 7.5; 95% CI 1.7–32.4; P=0.007) were independent risk factors for MTCT. Placental malaria was associated with a decrease in MTCT (AOR 0.23; 95% CI 0.06–0.89; P=0.034).Conclusions
IPTp with SP was not associated with a significant impact on MTCT of HIV. Maternal anaemia was an independent risk factor for MTCT. 相似文献37.
Stacee M. Lerret Marianne E. Weiss Gail L. Stendahl Shelley Chapman Jerome Menendez Laurel Williams Michelle L. Nadler Katie Neighbors Katie Amsden Yumei Cao Melodee Nugent Estella M. Alonso Pippa Simpson 《Pediatric transplantation》2015,19(1):118-129
Pediatric SOT recipients are medically fragile and present with complex care issues requiring high‐level management at home. Parents of hospitalized children have reported inadequate preparation for discharge, resulting in problems transitioning from hospital to home and independently self‐managing their child's complex care needs. The aim of this study was to investigate factors associated with the transition from hospital to home and chronic illness care for parents of heart, kidney, liver, lung, or multivisceral recipients. Fifty‐one parents from five pediatric transplant centers completed questionnaires on the day of hospital discharge and telephone interviews at three wk, three months, and six months following discharge from the hospital. Care coordination (p = 0.02) and quality of discharge teaching (p < 0.01) was significantly associated with parent readiness for discharge. Readiness for hospital discharge was subsequently significantly associated with post‐discharge coping difficulty (p = 0.02) at three wk, adherence with medication administration (p = 0.03) at three months, and post‐discharge coping difficulty (p = 0.04) and family management (p = 0.02) at six months post‐discharge. The results underscore the important aspect of education and care coordination in preparing patients and families to successfully self‐manage after hospital discharge. Assessing parental readiness for hospital discharge is another critical component for identifying risk of difficulties in managing post‐discharge care. 相似文献
38.
Schellenberg D Menendez C Aponte J Guinovart C Mshinda H Tanner M Alonso P 《Tropical medicine & international health : TM & IH》2004,9(1):68-76
Between 1995 and 2000 there were marked changes in the epidemiology of malaria in Ifakara, southern Tanzania. We documented these changes using parasitological and clinical data from a series of community- and hospital-based studies involving children up to the age of 5 years. There was a right shift and lowering in the age-specific parasite prevalence in the community-based cohort studies. The incidence of clinical malaria in placebo-receiving infants in additional study cohorts dropped from 0.8 in 1995 to 0.43 episodes per infant per year in 2000, an incidence rate ratio of 0.53 (95% confidence interval: 0.404, 0.70, P<0.0001). At the same time, there was an increase in the total number of malaria admissions and a marked right shift in the age pattern of these admissions (median age in 1995 1.55 years vs. 2.33 in 2000, P<0.0001). However, the burden of malaria deaths remained in infants. We discuss how these dramatic changes in the epidemiology of malaria may have arisen from the use of currently available malaria control tools. Caution is required in the interpretation of hospital-based data as it is likely to underestimate the impact of anaemia on mortality in the community, where most paediatric deaths occur. Even in low/moderate malaria transmission settings, where older children suffer most malaria episodes, targeting effective malaria control at infants may produce important reductions in infant mortality caused by malaria. 相似文献
39.
Toll‐like Receptor‐Mediated Responses by Placental Hofbauer Cells (HBCs): A Potential Pro‐Inflammatory Role for Fetal M2 Macrophages
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