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101.

Objective

Atherogenic dyslipidemia seems to play a major role in microvascular complications and in residual microvascular risk after statin therapy, which reduces triglycerides up to 40%. We assessed whether raised TG levels are associated with an increased burden from microvascular complications in patients with type 2 diabetes.

Methods

Subjects from the Renal Insufficiency And Cardiovascular Events (RIACE) Italian Multicentre Study (n=15,773) were divided in 4 groups depending on whether they had plasma triglycerides below (NTG, 67.8%) or above (HTG, 32.2%) 1.7 mmol/L and were (42.4%) or not on (57.6%) statin therapy. Estimated GFR (eGFR) was calculated from serum creatinine, albuminuria was measured by immunonephelometry or immunoturbidimetry, and retinopathy was evaluated by fundus examination.

Results

HTG subjects, either with or without statin, had higher prevalence of albuminuria, reduced eGFR and chronic kidney disease (CKD), especially the albuminuric forms, but not of retinopathy, than NTG subjects. In contrast, cardiovascular disease and advanced DR were more prevalent in subjects on statin than in those not, independently of triglyceride levels. Logistic regression analysis confirmed that HTG, without or with statin, was independently associated with micro and macroalbuminuria, mildly to severely reduced eGFR, and all CKD phenotypes, but not with retinopathy. The adjusted odd ratios for CKD increased linearly for every 0.26 mmol/L increase (approximately one decile) in triglyceride levels. The increase was higher with increasing severity of albuminuria, eGFR loss and CKD phenotype as well as in subjects receiving than in those not receiving statin treatment.

Conclusions

Triglycerides are associated with CKD, but not retinopathy in subjects with type 2 diabetes, independently of statin treatment. These data point to a possible role of hypertriglyceridemia in the development of CKD, though it remains to be demonstrated that diabetic individuals might benefit from triglyceride reduction with statins and eventually with combination therapy with fibrates.

Trial Registration

www.ClinicalTrials.gov NCT00715481  相似文献   
102.
通过考察阿托伐他汀(atorvastatin, ATO) 对自发性高血压大鼠(spontaneously hypertensive rats, SHR) 肾脏炎性损害的影响, 探讨了 ATO 对高血压肾脏并发症的防治作用。将4周龄SHR分为高血压模型组和ATO治疗组(8mg/kg),以同周龄的Wistar-Kyoto大鼠为正常对照。灌胃给药8周后, 采用酶联免疫法(enzyme linked immunosorbent assay)测定血浆和肾组织血管紧张素Ⅱ(angiotensin, AngⅡ)含量;测定诱导性一氧化氮合酶(inducible nitric oxide synthase, iNOS)及细胞间粘附分子-1(intercellular adhesion molecule-1, ICAM-1) 的蛋白表达和亚硝酸阴离子(nitrite, NO2-)含量,以评价肾脏炎症状态; 以苏木素伊红(hematoxylin and eosin)和过碘酸六胺银染色(periodic acid-silver metheramine) 染色示SHR肾小球和肾间质形态学病变,并以尿蛋白含量为指标衡量肾脏功能。结果显示...  相似文献   
103.
为便于本地社区了解当地生态系统的复杂性,以便在得益于自然环境的同时更好地珍视、利用和保护,国际山地综合发展中心(ICIMOD)联合其他环保组织提出了“神山圣湖山水自然保护倡议”(KSLCI),制作了圣地区域的手绘宣传图册,其目的在于,协助山地乡村社区更好地了解本地所面临的变化和机遇。手册以生活于冈仁波齐(Kailash)圣地的本地社区为服务对象,也可为范围更大的山地社区提供助益。  相似文献   
104.
人干扰素ω(huIFN-ω)的高效表达、纯化及生物学活性   总被引:2,自引:0,他引:2  
为了获得人干扰素-ω(huIFN-ω)在大肠杆菌中的高效表达,根据大肠杆菌的偏爱密码子,人工设计并合成了huIFN-ω高表达基因,并克隆到原核表达载体pBV220,在大肠杆菌DH5α中实现了高效表达,目的蛋白占细胞总蛋白的15%左右,以包涵体形式存在.表达产物经变性、复性及阳离子和分子筛层析纯化,纯度达90%以上,产物的抗病毒活性约为1.0×108IU/mg,并具有体外促NK杀伤活性.此结果为进一步研究和开发重组huIFN-ω奠定了基础.  相似文献   
105.

Background

Type 2 diabetes mellitus is associated with risk of congestive heart failure (CHF), cognitive dysfunction and depression. CHF itself is linked both to poor cognition and depression. The ventricular N-terminal pro-brain natriuretic peptide (NT-proBNP) is a marker of CHF, suggesting potential as a marker for cognitive impairment and/or depression. This was tested in the Edinburgh Type 2 Diabetes Study (ET2DS).

Methodology and Principal Findings

Cross-sectional analysis of 1066 men and women aged 60–75 with type 2 diabetes. Results from seven neuropsychological tests were combined in a standardised general cognitive ability factor, ‘g’. A vocabulary-based test estimated pre-morbid cognitive ability. The Hospital Anxiety and Depression Scale (HADS) assessed possible depression. After adjustment for age and sex, raised plasma NT-proBNP was weakly associated with lower ‘g’ and higher depression scores (ß −0.09, 95% CI −0.13 to −0.03, p = 0.004 and ß 0.08, 95% CI 0.04 to 0.12, p<0.001, respectively). Comparing extreme quintiles of NT-proBNP, subjects in the highest quintile were more likely to have reduced cognitive ability (within the lowest tertile of ‘g’) and ‘possible’ depression (HADS depression ≥8) (OR 1.80; 95% CI: 1.20, 2.70; p = 0.005 and OR 2.18; 95% CI: 1.28, 3.71; p = 0.004, respectively). Associations persisted when pre-morbid ability was adjusted for, but as expected were no longer statistically significant following the adjustment for diabetes-related and vascular co-variates (β −0.02, 95% CI −0.07 to 0.03, p>0.05 for ‘g’; β 0.03, 95% CI −0.02 to 0.07, p>0.05 for depression scores).

Conclusion

Raised plasma NT-proBNP was weakly but statistically significantly associated with poorer cognitive function and depression. The prospective phases of the ET2DS will help determine whether or not NT-proBNP can be considered a risk marker for subsequent cognitive impairment and incident depression and whether it provides additional information over and above traditional risk factors for these conditions.  相似文献   
106.

Background

Colorectal cancer (CRC) is considered a complex disease, and thus the majority of the genetic susceptibility is thought to lie in the form of low-penetrance variants following a polygenic model of inheritance. Candidate-gene studies have so far been one of the basic approaches taken to identify these susceptibility variants. The consistent involvement of some signaling routes in carcinogenesis provided support for pathway-based studies as a natural strategy to select genes that could potentially harbour new susceptibility loci.

Methodology/Principal Findings

We selected two main carcinogenesis-related pathways: Wnt and BMP, in order to screen the implicated genes for new risk variants. We then conducted a case-control association study in 933 CRC cases and 969 controls based on coding and regulatory SNPs. We also included rs4444235 and rs9929218, which did not fulfill our selection criteria but belonged to two genes in the BMP pathway and had consistently been linked to CRC in previous studies. Neither allelic, nor genotypic or haplotypic analyses showed any signs of association between the 37 screened variants and CRC risk. Adjustments for sex and age, and stratified analysis between sporadic and control groups did not yield any positive results either.

Conclusions/Significance

Despite the relevance of both pathways in the pathogenesis of the disease, and the fact that this is indeed the first study that considers these pathways as a candidate-gene selection approach, our study does not present any evidence of the presence of low-penetrance variants for the selected markers in any of the considered genes in our cohort.  相似文献   
107.

Background

Increased mortality among men on antiretroviral therapy (ART) has been documented but remains poorly understood. We examined the magnitude of and risk factors for gender differences in mortality on ART.

Methods and Findings

Analyses included 46,201 ART-naïve adults starting ART between January 2002 and December 2009 in eight ART programmes across South Africa (SA). Patients were followed from initiation of ART to outcome or analysis closure. The primary outcome was mortality; secondary outcomes were loss to follow-up (LTF), virologic suppression, and CD4+ cell count responses. Survival analyses were used to examine the hazard of death on ART by gender. Sensitivity analyses were limited to patients who were virologically suppressed and patients whose CD4+ cell count reached >200 cells/µl. We compared gender differences in mortality among HIV+ patients on ART with mortality in an age-standardised HIV-negative population.Among 46,201 adults (65% female, median age 35 years), during 77,578 person-years of follow-up, men had lower median CD4+ cell counts than women (85 versus 110 cells/µl, p<0.001), were more likely to be classified WHO stage III/IV (86 versus 77%, p<0.001), and had higher mortality in crude (8.5 versus 5.7 deaths/100 person-years, p<0.001) and adjusted analyses (adjusted hazard ratio [AHR] 1.31, 95% CI 1.22–1.41). After 36 months on ART, men were more likely than women to be truly LTF (AHR 1.20, 95% CI 1.12–1.28) but not to die after LTF (AHR 1.04, 95% CI 0.86–1.25). Findings were consistent across all eight programmes. Virologic suppression was similar by gender; women had slightly better immunologic responses than men. Notably, the observed gender differences in mortality on ART were smaller than gender differences in age-standardised death rates in the HIV-negative South African population. Over time, non-HIV mortality appeared to account for an increasing proportion of observed mortality. The analysis was limited by missing data on baseline HIV disease characteristics, and we did not observe directly mortality in HIV-negative populations where the participating cohorts were located.

Conclusions

HIV-infected men have higher mortality on ART than women in South African programmes, but these differences are only partly explained by more advanced HIV disease at the time of ART initiation, differential LTF and subsequent mortality, and differences in responses to treatment. The observed differences in mortality on ART may be best explained by background differences in mortality between men and women in the South African population unrelated to the HIV/AIDS epidemic. Please see later in the article for the Editors'' Summary.  相似文献   
108.
The Bhas promotion assay is a cell culture transformation assay designed as a sensitive and economical method for detecting the tumour-promoting activities of chemicals. In order to validate the transferability and applicability of this assay, an inter-laboratory collaborative study was conducted with the participation of 14 laboratories. After confirmation that these laboratories could obtain positive results with two tumour promoters, 12-O-tetradecanoylphorbol-13-acetate (TPA) and lithocholic acid (LCA), 12 coded chemicals were assayed. Each chemical was tested in four laboratories. For eight chemicals, all four laboratories obtained consistent results, and for two of the other four chemicals, only one of the four laboratories showed inconsistent results. Thus, the rate of consistency was high. During the study, several issues were raised, each of which were analysed step-by-step, leading to revision of the protocol of the original assay. Among these issues were the importance of careful maintenance of mother cultures and the adoption of test concentrations for toxic chemicals. In addition, it is suggested that three different types of chemicals show positive promoting activity in the assay. Those designated as T-type induced extreme growth enhancement, and included TPA, mezerein, PDD and insulin. LCA and okadaic acid belonged to the L-type category, in which transformed foci were induced at concentrations showing growth-inhibition. In contrast, M-type chemicals, progesterone, catechol and sodium saccharin, induced foci at concentrations with little or slight growth inhibition. The fact that different types of chemicals similarly induce transformed foci in the Bhas promotion assay may provide clues for elucidating mechanisms of tumour promotion.  相似文献   
109.

Background

In a cross-sectional analysis of cystic fibrosis (CF) patients with mild lung disease, reduced surfactant activity was correlated to increased neutrophilic airway inflammation, but not to lung function. So far, longitudinal measurements of surfactant function in CF patients are lacking and it remains unclear how these alterations relate to the progression of airway inflammation as well as decline in pulmonary function over time.

Methods

As part of the BEAT trial, a longitudinal study to assess the course of airway inflammation in CF, we studied lung function, surfactant function and endobronchial inflammation using bronchoalveolar lavage fluid from 20 CF patients with normal pulmonary function (median FEV1 94% of predicted) at three times over a three year period.

Results

There was a progressive loss of surfactant function, assessed as minimal surface tension. The decline in surfactant function was negatively correlated to an increase in neutrophilic inflammation and a decrease in lung function, assessed by FEV1, MEF75/25%VC, and MEF25%VC. The concentrations of the surfactant specific proteins A, C and D did not change, whereas SP-B increased during this time period.

Conclusion

Our findings suggest a link between loss of surfactant function driven by progressive airway inflammation and loss of small airway function in CF patients with limited lung disease.  相似文献   
110.
半滑舌鳎早期形态及发育特征   总被引:52,自引:0,他引:52  
半滑舌鳎卵子为分离的球形浮性卵 ,卵径 1 18-1 3 1mm。卵膜薄、光滑、透明 ,具弹性。多油球 ,一般为 97-12 5个 ,多数在 10 0个左右 ,油球径 0 0 4-0 11mm。在培养水温为 2 0 5-2 2 8℃的条件下 ,卵子授精后 3 7h仔鱼孵出 ,3 0min后仔鱼全部孵出。初孵仔鱼全长 2 56-2 68mm。 1日龄仔鱼 ,出现胸鳍芽。 1 5日龄仔鱼 ,巡游模式基本建立。 2日龄仔鱼 ,逐渐建立外源性摄食关系。 3日龄仔鱼 ,出现鳔泡 ,个体发育进入后期仔鱼期。 18日龄 ,个体发育进入稚鱼期。 2 5日龄稚鱼 ,右眼开始向上移动。 2 7日龄稚鱼 ,右眼已转到头顶。 2 9日龄稚鱼 ,右眼完全转到左侧 ,胸鳍退化 ,各鳍鳍条发育完全。 57日龄 ,个体发育进入幼鱼期。 79日龄幼鱼 ,鳔退化、鳞片发育完全 ,侧线 3条。研究结果表明 :前期仔鱼培育期间 ,除了严格控制适宜的培养水温外 ,仔鱼开口后就应及时投喂一定密度的适口饵料 ,这是苗种培育中不可忽视的重要环节和技术措施之一 ;稚鱼变态期间加强鲜活饵料的投喂是提高稚鱼变态成活率的关键所在。仔鱼孵化后出现的管状感觉器官以及背、臀鳍膜上的泡状结构在早期发育阶段的生态和生理作用尚不清楚。半滑舌鳎成鱼无鳔和无胸鳍 ,而在早期发育期间具有鳔泡和胸鳍 ,这是生物个体发育史中祖先特征的重演  相似文献   
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