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41.
OBJECTIVE: Although combinations of different antiretroviral drugs are increasingly used by pregnant HIV-1-infected women, few human data are available to evaluate in utero protease inhibitors (PI) exposure. The aim of this study was to assess the extent of transplacental passage of PI at delivery. METHODS: Pregnant women treated with antiretroviral drugs including PI and/or nevirapine were eligible for the study. Placental transfer was determined by comparison of drug concentrations in blood samples simultaneously collected from a peripheral maternal vein and the umbilical cord at delivery. Drug levels were determined by high-performance liquid chromatography. RESULTS: Thirteen maternal-cord blood sample pairs were evaluable for transplacental passage determination (nine nelfinavir, two ritonavir, one saquinavir, one lopinavir, two nevirapine). Median cord and maternal drug concentrations, respectively, were nelfinavir < 250 and 1110 ng/ml; ritonavir < 250 and 1113 ng/ml; saquinavir < 100 and 350 ng/ml; lopinavir < 250 and 3105 ng/ml and nevirapine 2072 and 2546 ng/ml. The cord-to-maternal blood ratio was extremely low for all PI. CONCLUSION: PI do not cross the placenta to an appreciable extent and consequently cannot be expected to exert a direct antiviral activity in utero during the whole dosing interval. Limited transfer may result from their high degree of plasma protein binding and their backwards transport through P-glycoprotein, largely expressed in the placenta. In contrast, nevirapine readily crosses the placental barrier. Such considerations may support treatment decisions in pregnant women.  相似文献   
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CONTEXT: The recently discovered hormone resistin is linked to the development of insulin resistance, but direct evidence of resistin levels in humans with nonalcoholic fatty liver disease (NAFLD) is lacking. METHODS: We conducted this study to assess the relationship between serum resistin and NAFLD. We measured serum resistin and biochemical, hormonal, and histological correlates in 28 NAFLD patients, 33 controls, and 30 obese patients [body mass index (BMI), >30 kg/m2] without NAFLD. RESULTS: Resistin and adiponectin expression were measured in sc adipose tissue by quantitative RT-PCR. Resistin was higher in NAFLD patients compared with controls (5.87 +/- 0.49 vs. 4.30 +/- 0.20 ng/ml; P = 0.002) and obese patients (4.37 +/- 0.27 ng/ml; P = 0.002). Increased resistin mRNA was also found in the adipose tissue of NAFLD patients compared with controls and obese subjects. CONCLUSIONS: Both NAFLD and obese patients had lower adiponectin levels, whereas leptin was increased only in the obese group. No correlation was found between resistin and high-sensitivity C-reactive protein, BMI, homeostasis model assessment, insulin, glucose, transaminases, and lipid values. A positive correlation was found between resistin and histological inflammatory score. These data report increased resistin in NAFLD patients that is related to the histological severity of the disease, but do not support a link between resistin and insulin resistance or BMI in these patients.  相似文献   
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Proteins involved in zinc homeostasis may be altered in aging. This phenomenon may lead to zinc deficiency in the peripheral blood and an accumulation of zinc bound to insoluble aggregates at the extracellular level in the brain. Therefore, it should be more correct to talk about aging as a condition associated with zinc dyshomeostasis rather than deficiency. Restoring functional zinc homeostasis in aging people is an attractive field for antiaging research, but requires further knowledge than the current state of the art.  相似文献   
44.
Oncogenic rearrangements of the tyrosine kinase receptor anaplastic lymphoma kinase (ALK), most commonly represented by the nucleophosmin/ALK fusion protein (NPM/ALK), are involved in the pathogenesis of anaplastic large-cell lymphomas (ALCLs). In an effort to identify new intracellular transducers operative in ALK-positive malignancies, we have investigated the potential involvement of diacylglycerol kinase (DGK). Here we show that alphaDGK is constitutively activated in the NPM/ALK-positive ALCL-derived cell line Karpas 299 and in NPM/ALK-infected 32D hematopoietic cells. These results were further validated in fibroblastic NIH-3T3 cells expressing a previously described chimeric epidermal growth factor receptor (EGFR)/ALK molecule that allows dissection of ALK enzymatic function under conditions of controlled ligand-induced activation. In this cell system, we also show that ALK-mediated alphaDGK activation is dependent on p60src tyrosine kinase, with which alphaDGK forms a complex. The specific inhibition of alphaDGK, obtained by cell treatment with R59949, significantly reduced cellular growth in all cell lines. This result was further confirmed in Karpas 299 cells following specific down-regulation of alphaDGK by RNA interference. Overall, our data indicate that alphaDGK activation is involved in the control of ALK-mediated mitogenic properties.  相似文献   
45.
Prognostic significance of blood pressure measured on rising.   总被引:1,自引:0,他引:1  
Previous works using ambulatory blood pressure (BP) monitoring demonstrated that independently of the mean level of BP, the variability in BP, or the day-night range, could have prognostic significance. We have also found that the value of BP on rising in the morning is strongly correlated with left ventricular mass of hypertensive individuals independently of the 24-h value. In the present study, we sought its predictive value for cardiovascular complications in a cohort of hypertensive patients. The population studied belongs to a cohort of initially untreated hypertensive patients recruited since 1983 and followed for more than 5 years. Patients were then treated and followed by their family doctor. At entry, all patients were equipped with a device to measure ambulatory BP. They were requested to trigger a measurement manually on rising in the morning (arising BP). The data on their outcome were collected by a physician unaware of the initial state of the patients. A total of 256 patients have been followed up for 5 years or more, 19 were lost to follow-up. The mean follow-up period was 84 +/- 29 months. Cardiovascular complications were recorded in 23 individuals. The arising systolic BP (SBP) was significantly higher in the group who presented a complication. In a stepwise discriminant analysis including age, office, fitting, arising and 24-h average SBPs only age and arising SBP entered the equation. In conclusion, the single BP value measured by an ambulatory device on rising in the morning seems more discriminant of future cardiovascular events than the value of BP measured on fitting the device or the average of three measurements taken under standardised conditions in the hospital or office.  相似文献   
46.
A number of new 9,10-anthracenediones were obtained, bearing one or two hydroxyl groups and one positively charged side chain at different positions of the aromatic ring system (compounds 1-5 in Chart 1). These derivatives resemble the anticancer agents mitoxantrone and ametantrone. The synthesis started from dihydroxy- or amino-hydroxy-9,10-anthracenediones, which were converted into the nitro-derivatives. After reduction to the corresponding amines and acylation with 3-chloropropionyl chloride, substitution with diethylamine led to the final diethylaminopropionamido derivatives. The new anthracenediones cause a quite relevant inhibition of cell growth in vitro and will be tested as possible anticancer agents.  相似文献   
47.
Introduction  During aging, dysregulated immune functions occur contributing to increased susceptibility to morbidity and mortality. However, these dysregulations are normally counterbalanced by continuous adaptation of the body to the deteriorative changes occurring over time. These adaptive changes well occur in healthy centenarians. Discussion  Both innate (natural) and adaptive (acquired) immune responses decline with advancing age. Natural killer (NK) and natural killer T (NKT) cell cytotoxicity, representing one of best models of innate immune response, decreases in aging as well as interferon-γ (IFN-γ) production by both activated types of cells. Both NK and NKT cell cytotoxicity and IFN-γ production increase in very old age with respect to normal aging, especially by NKT cells bearing TCRγδ. The role played by zinc and metallothioneins (MT) is crucial because this affects NK and NKT cell development, maturation, and functions. In particular, some MT polymorphisms are involved in maintaining innate immune response and intracellular zinc ion availability in aging with thus a role of MT genetic background to escape some age-related diseases with subsequent healthy aging and longevity.  相似文献   
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