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OBJECTIVES: The aim of this study was to evaluate the serum lipid profile and to assess the prevalence of hepatic steatosis in adult beta-thalassaemic patients with chronic hepatitis C virus (HCV) infection. METHODS: Thirty-five adult HCV infected, multi-transfused, beta-thalassaemia patients (beta-HCV patients), 63 otherwise normal patients with chronic HCV infection (HCV patients) and 54 beta-thalassaemia patients without chronic viral hepatitis (beta patients) were studied. Total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides, viral markers and liver histology were evaluated. RESULTS: Serum total cholesterol, HDL-C and LDL-C were found at significantly lower levels in beta-HCV and beta patients than in HCV patients. Triglyceride levels were significantly lower in the HCV group compared with the beta group. Nine (25.7%) of the 35 beta-HCV patients had mild hepatic steatosis. Thirteen (23.6%) of 55 HCV patients presented mild and 4/55 (7.3%) moderate hepatic steatosis. None of the beta group presented steatosis. When we compared beta-HCV and HCV patients with steatosis, we found that beta-HCV patients had a lower degree of steatosis (11.1+/-7% vs 22.9+/-17.2%, P=0.021). Multivariate logistic regression analysis showed that the only independent predictor associated with hepatic steatosis in beta-HCV and HCV patients was genotype 3a (OR, 3.61; 95% CI, 1.22-10.71, P=0.021). CONCLUSIONS: Adult beta-thalassaemia patients, compared to other patients with chronic HCV infection, present lower cholesterol levels (total cholesterol, HDL, LDL) and similar frequency but a lower degree of hepatic steatosis. This difference in the degree of steatosis is most likely due to the higher prevalence of genotype 3a in the non-beta-thalassaemia group.  相似文献   
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Black carbon (BC) is increasingly recognized as a significant air pollutant with harmful effects on human health, either in its own right or as a carrier of other chemicals. The adverse impact is of particular concern in those developing regions with high emissions and a growing population density. The results of recent studies indicate that BC emissions could be underestimated by a factor of 2–3 and this is particularly true for the hot-spot Asian region. Here we present a unique inventory at 10-km resolution based on a recently published global fuel consumption data product and updated emission factor measurements. The unique inventory is coupled to an Asia-nested (∼50 km) atmospheric model and used to calculate the global population exposure to BC with fully quantified uncertainty. Evaluating the modeled surface BC concentrations against observations reveals great improvement. The bias is reduced from −88% to −35% in Asia when the unique inventory and higher-resolution model replace a previous inventory combined with a coarse-resolution model. The bias can be further reduced to −12% by downscaling to 10 km using emission as a proxy. Our estimated global population-weighted BC exposure concentration constrained by observations is 2.14 μg⋅m−3; 130% higher than that obtained using less detailed inventories and low-resolution models.Black carbon (BC), or soot, emitted from incomplete combustion of carbonaceous fuels is an air pollutant which also plays an important role in climate change (1). BC is an indicator of air particulate pollution and BC in ambient air has an impact on human health (2). In a recent study in China, it was found that the effects of BC on morbidity appear to be more robust than the effects of fine particles in general (3, 4).However, global atmospheric aerosol models often underestimate the concentration of BC at the surface, particularly over Asia, by a factor that typically ranges from 2 to 10 (57). In one study, the observed BC surface concentration for China could only be reproduced by doubling the emissions prescribed to a transport model (8). It is often argued that the underestimation is due to a low bias in BC emission inventories, suggesting a need to revisit these previous inventories (9).In a bottom-up approach, BC emission is estimated based on the amount of fuel consumed and an emission factor (EFBC, defined as the amount of BC emitted per unit mass of fuel consumed) for each of various combustion sources. For previous inventories, the lack of EFBC measurements in developing countries led to high uncertainty in estimating the total emissions (10). In addition, the use of fuel data at the national level is likely to distort the geographical distribution of emissions within large countries such as China and India (11). Recently, a 0.1° × 0.1° fuel database with 64 types of combustion has been developed based on local or national fuel consumption statistics. This database improves the resolution of the spatial distribution of emissions for large countries (12). To fill the data gap in developing countries, a set of EFBC values has been compiled for various residential solid fuel combustion devices and vehicles (1320). In addition to the problems with the emission inventories, the coarse resolution of existing global aerosol models also hinders our ability to capture detailed spatial variation, leading to poor agreement between model prediction and observations (7).In this study we develop and evaluate a unique global BC emission inventory using a zoomed aerosol model, and estimate the global population’s exposure to BC with a focus on Asia. The influence of model resolution and the use of an updated emission inventory on the calculated BC concentration are evaluated against field observations.  相似文献   
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Chronic kidney disease(CKD) patients face an unacceptably high morbidity and mortality, mainly from cardiovascular diseases. Diabetes mellitus, arterial hypertension and dyslipidemia are highly prevalent in CKD patients. Established therapeutic protocols for the treatment of diabetes mellitus, arterial hypertension,and dyslipidemia are not as effective in CKD patients as in the general population. The role of non-traditional risk factors(RF) has gained interest in the last decades. These entail ...  相似文献   
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Hyalinizing trabecular tumors of the thyroid are rare and mostly benign epithelial neoplasms of follicular cell origin, which have recently been shown to be underpinned by the PAX8-GLIS3 fusion gene. In our study, we sought to investigate the potential oncogenic mechanisms of the PAX8-GLIS3 fusion gene. Forced expression of PAX8-GLIS3 was found to increase proliferation, clonogenic potential and migration of human nonmalignant thyroid (Nthy-ori 3-1) and embryonic kidney (HEK-293) cells. Moreover, in xenografts, Nthy-ori 3-1 PAX8-GLIS3 expressing cells generated significantly larger and more proliferative tumors compared to controls. These oncogenic effects were found to be mediated through activation of the Sonic Hedgehog (SHH) pathway. Targeting of smoothened (SMO), a key protein in the SHH pathway, using the small molecule inhibitor Cyclopamine partially reversed the increased proliferation, colony formation and migration in PAX8-GLIS3 expressing cells. Our data demonstrate that the oncogenic effects of the PAX8-GLIS3 fusion gene are, at least in part, due to an increased activation of the SHH pathway.  相似文献   
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The role of dopamine in regulating sleep‐state transitions during, both natural sleep and under anaesthesia, is still unclear. Recording in vivo in the rat mPFC under urethane anaesthesia, we observed predominantly slow wave activity (SWA) of <1 Hz in the local field potential interrupted by occasional spontaneous transitions to a low‐amplitude‐fast (LAF) pattern of activity. During periods of SWA, transitions to LAF activity could be rapidly and consistently evoked by electrical stimulation of the ventral tegmental area (VTA). Spontaneous LAF activity, and that evoked by stimulation of the VTA, consisted of fast oscillations similar to those seen in the rapid eye movement (REM)‐like sleep state. Spontaneous and VTA stimulation‐evoked LAF activity occurred simultaneously along the dorsoventral extent of all mPFC subregions. Evoked LAF activity depended on VTA stimulation current and could be elicited using either regular (25–50 Hz) or burst stimulation patterns and was reproducible upon repeated stimulation. Simultaneous extracellular single‐unit recordings showed that during SWA, presumed pyramidal cells fired phasically and almost exclusively on the Up state, while during both spontaneous and VTA‐evoked LAF activity, they fired tonically. The transition to LAF activity evoked by VTA stimulation depended on dopamine D1‐like receptor activation as it was almost completely blocked by systemic administration of the D1‐like receptor antagonist SCH23390. Overall, our data demonstrate that activation of dopamine D1‐like receptors in the mPFC is important for regulating sleep‐like state transitions.  相似文献   
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Congenital seminal vesicle cysts associated with renal agenesis are uncommon, but are currently detected more frequently with the use of sectional imaging procedures. Approximately 200 cases have been reported. The unique feature of our case is the combination of this disorder with an ipsilateral undescended testis. Our patient underwent partial vesiculectomy, in which the cyst was removed and the seminal vesicle remnant with its vas deferens was preserved. A review of the infertile cases and the impact of surgical treatment on fertility are discussed. Features that render partial vesiculectomy applicable and the potential effect of this procedure on fertility are highlighted.  相似文献   
10.
Exposure to organochlorine compounds and effects on ovarian function   总被引:1,自引:0,他引:1  
BACKGROUND: Some chemicals appear to have hormonally active properties in animals, but data in humans are sparse. Therefore, we examined ovarian function in relation to organochlorine compound levels. METHODS: During 1997-1999, 50 Southeast Asian immigrant women of reproductive age collected urine samples daily. These samples were assayed for metabolites of estrogen and progesterone, and the women's menstrual cycle parameters were assessed. Organochlorine compounds (including DDT, its metabolite DDE, and 10 polychlorinated biphenyl [PCB] congeners) were measured in serum. RESULTS: All samples had detectable DDT and DDE, with mean levels higher than typical U.S. populations. Mean cycle length was approximately 4 days shorter at the highest quartile concentration of DDT or DDE compared with the lowest. After adjustment for lipid levels, age, parity, and tubal ligation, and exclusion of a particularly long cycle, the decrements were attenuated to less than 1 day, with wide confidence intervals (CIs). The adjusted mean luteal phase length was shorter by approximately 1.5 days at the highest quartile of DDT (95% CI = -2.6 to -0.30) or DDE (-2.6 to -0.20). With each doubling of the DDE level, cycle length decreased 1.1 day (-2.4 to 0.23) and luteal phase length decreased 0.6 days (-1.1 to -0.2). Progesterone metabolite levels during the luteal phase were consistently decreased with higher DDE concentration. PCB levels were not generally associated with cycle length or hormone parameters after adjustment, and they did not alter the DDE associations when included in the same models. CONCLUSIONS: This study indicates a potential effect of DDE on ovarian function, which may influence other end points such as fertility, pregnancy, and reproductive cancers.  相似文献   
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