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11.

Background

Impaired glucose tolerance (IGT) is a prediabetic state. If IGT can be prevented from progressing to overt diabetes, hyperglycemia-related complications can be avoided. The purpose of the present study was to examine whether pioglitazone (ACTOS®) can prevent progression of IGT to type 2 diabetes mellitus (T2DM) in a prospective randomized, double blind, placebo controlled trial.

Methods/Design

602 IGT subjects were identified with OGTT (2-hour plasma glucose = 140–199 mg/dl). In addition, IGT subjects were required to have FPG = 95–125 mg/dl and at least one other high risk characteristic. Prior to randomization all subjects had measurement of ankle-arm blood pressure, systolic/diastolic blood pressure, HbA1C, lipid profile and a subset had frequently sampled intravenous glucose tolerance test (FSIVGTT), DEXA, and ultrasound determination of carotid intima-media thickness (IMT). Following this, subjects were randomized to receive pioglitazone (45 mg/day) or placebo, and returned every 2–3 months for FPG determination and annually for OGTT. Repeat carotid IMT measurement was performed at 18 months and study end. Recruitment took place over 24 months, and subjects were followed for an additional 24 months. At study end (48 months) or at time of diagnosis of diabetes the OGTT, FSIVGTT, DEXA, carotid IMT, and all other measurements were repeated. Primary endpoint is conversion of IGT to T2DM based upon FPG ≥ 126 or 2-hour PG ≥ 200 mg/dl. Secondary endpoints include whether pioglitazone can: (i) improve glycemic control (ii) enhance insulin sensitivity, (iii) augment beta cell function, (iv) improve risk factors for cardiovascular disease, (v) cause regression/slow progression of carotid IMT, (vi) revert newly diagnosed diabetes to normal glucose tolerance.

Conclusion

ACT NOW is designed to determine if pioglitazone can prevent/delay progression to diabetes in high risk IGT subjects, and to define the mechanisms (improved insulin sensitivity and/or enhanced beta cell function) via which pioglitazone exerts its beneficial effect on glucose metabolism to prevent/delay onset of T2DM.

Trial Registration

clinical trials.gov identifier: NCT00220961  相似文献   
12.
Industrial microbiology of solar salt production   总被引:3,自引:0,他引:3  
Solar salterns can be modeled as giant outdoor chemostats, much like a series of dams on a slow-moving river. Microorganisms and their products play an essential, but sometimes uncharacterized, role in salt production in these ponds, from seawater salinity up through NaCl saturation. They may physically affect the evaporation process and their by-products may chemically modify or bind with dissolved ions. Many solar salt facilities engage microbiologists to establish monitoring programs for analyses of nutrients, standing crop and associated biological variables in the ponds. Other solar salt companies engage microbiologists only when there are “crises” in the ponds that interfere with salt production. Journal of Industrial Microbiology & Biotechnology (2002) 28, 42–47 DOI: 10.1038/sj/jim/7000173 Received 20 May 2001/ Accepted in revised form 13 June 2001  相似文献   
13.
This paper investigates the spatial heterogeneity of landowners’ willingness to supply three bioenergy crops: switchgrass, Miscanthus, and willow, in the northeastern United States. Spatial heterogeneity might arise for several reasons. For example, landowners closer to bioenergy processing plants might be more likely to be willing to supply bioenergy crops, and landowners who are more willing to supply bioenergy crops may be spatially clustered because they share similar land attributes, demographics, experiences, and/or values. Using high‐resolution GIS data related to the location of pellet plants utilizing bioenergy crops and survey data related to landowners’ characteristics including spatial location, we estimate a spatial probit model to explain the variation in individual‐specific reservation prices (RPs)—the feedstock price at which landowners become willing to supply a bioenergy crop. We find that respondents’ RP is lower the closer they live to their nearest pellet plant and spatial dependency is only present for switchgrass supply. We also identify three economic hotspots (areas with high potential supply and low RPs) for each bioenergy crop. We believe that bioenergy supply chains could be developed around these hotspots.  相似文献   
14.
T helper (Th)17 cells represent a unique subset of CD4+ T cells and are vital for clearance of extracellular pathogens including bacteria and fungi. However, Th17 cells are also involved in orchestrating autoimmunity. By employing quantitative surface proteomics, we found that the evolutionarily conserved prohibitins (PHB1/2) are highly expressed on the surface of both murine and human Th17 cells. Increased expression of PHBs at the cell surface contributed to enhanced CRAF/MAPK activation in Th17 cells. Targeting surface‐expressed PHBs on Th17 cells with ligands such as Vi polysaccharide (Typhim vaccine) inhibited CRAF‐MAPK pathway, reduced interleukin (IL)‐17 expression and ameliorated disease pathology with an increase in FOXP3+‐expressing Tregs in an animal model for multiple sclerosis (MS). Interestingly, we detected a CD4+ T cell population with high PHB1 surface expression in blood samples from MS patients in comparison with age‐ and sex‐matched healthy subjects. Our observations suggest a pivotal role for the PHB‐CRAF‐MAPK signalling axis in regulating the polarization and pathogenicity of Th17 cells and unveil druggable targets in autoimmune disorders such as MS.  相似文献   
15.
There is a need for safe medications that can effectively support recovery by treating symptoms of protracted abstinence that may precipitate relapse in alcoholics, e.g. craving and disturbances in sleep and mood. This proof-of-concept study reports on the effectiveness of gabapentin 1200 mg for attenuating these symptoms in a non-treatment-seeking sample of cue-reactive, alcohol-dependent individuals. Subjects were 33 paid volunteers with current Diagnostic and Statistical Manual of Mental Disorders-IV alcohol dependence and a strength of craving rating 1 SD or greater for alcohol than water cues. Subjects were randomly assigned to gabapentin or placebo for 1 week and then participated in a within-subjects trial where each was exposed to standardized sets of pleasant, neutral and unpleasant visual stimuli followed by alcohol or water cues. Gabapentin was associated with significantly greater reductions than placebo on several measures of subjective craving for alcohol as well as for affectively evoked craving. Gabapentin was also associated with significant improvement on several measures of sleep quality. Side effects were minimal, and gabapentin effects were not found to resemble any major classes of abused drugs. Results suggest that gabapentin may be effective for treating the protracted abstinence phase in alcohol dependence and that a randomized clinical trial would be an appropriate next step. The study also suggests the value of cue-reactivity studies as proof-of-concept screens for potential antirelapse drugs.  相似文献   
16.
Abstract: In North America, brown bears (Ursus arctos) can be a significant predator on moose (Alces alces) calves. Our study in Sweden is the first in which brown bears are the only predator on moose calves. Bears and moose occurred at densities of about 30/1,000 km2 and 920/1,000 km2, respectively, and bears killed about 26% of the calves. Ninety-two percent of the predation took place when calves were <1 month old. Bear predation was probably additive to other natural mortality, which was about 10% in areas both with and without bears. Females that lost their calves in spring produced more calves the following year (1.54 calves/F) than females that kept their calves (1.11 calves/F), which reduced the net loss of calves due to predation to about 22%.  相似文献   
17.
18.
The influence of local heating of the skin on the integrated EMG (registered with surface and subcutaneous electrodes), the amplitude of the ECG, the skin blood flow, the electrode impedance, the electrode-to-skin impedance, and the tissue impedance is investigated. Except for the increasing skin blood flow each of the variables exhibits a significant reduction with an increase in skin temperature. From these results the existence of two mechanisms is deduced mediating thermal influence on bioelectric signals picked up by surface electrodes: 1. An alteration of the signal source. 2. An alteration of the electric transfer characteristics of the tissue between signal source and electrode. Especially in quantitative surface electromyography the temperature dependence of the signal can be a source of error.  相似文献   
19.
The temperature and cell volume dependence of the NMR water proton linewidth, spin-lattice, and spin-spin relaxation times have been studied for normal and sickle erythrocytes as well as hemoglobin A and hemoglobin S solutions. Upon deoxygenation, the spin-spin relaxation time (T2) decreases by a factor of 2 for sickle cells and hemoglobin S solutions but remains relatively constant for normal cells and hemoglobin A solutions. The spin-lattice relaxation time (T1) shows no significant change upon dexygenation for normal or sickle packed red cells. Studies of the change in the NMR linewidth, T1 and T2 as the cell hydration is changed indicate that these parameters only slightly by a 10–20% cell dehydration. This result suggests that the reported 10% cell dehydration observed with sickling is not important in the altered NMR properties. Low temperature studies of the linewidth and T1 for oxy and deoxy hemoglobin A and hemoglobin S solutions suggest that the “bound” water possesses similar properties for all four species. The low temperature linewidth ranges from about 250 Hz at ?15°C to 500 Hz at ?36°C and analysis of the NMR curves yield hydration values near 0.4 g water/g hemoglobin for all four species. The low temperature T1 data go through a minimum at ?35°C for measurements at 44.4 MHz and ?50°C for measurements at 17.1 MHz and are similar for oxy and deoxy hemoglobin A and hemoglobin S. These similarities in the low temperature NMR data for oxy and deoxy hemoglobin A and hemoglobin S suggest a hydrophobically driven sickling mechanism. The room temperature and low temperature relaxation time data for normal and sickle cells are interpreted in terms of a three-state model for intracellular water. In the context of this model the relaxation time data imply that type III, or irratationally bound water, is altered during the sickling process.  相似文献   
20.
The effects of the trichothecene mycotoxins (acetyl T-2 toxin, T-2 toxin, HT-2 toxin, palmityl T-2 toxin, diacetoxyscirpenol (DAS), deoxynivalenol (DON), and T-2 tetraol) on bovine platelet function were examined in homologous plasma stimulated with platelet activating factor (PAF). The mycotoxins inhibited platelet function with the following order of potency: acetyl T-2 toxin > palmityl T-2 toxin = DAS > HT-2 toxin = T-2 toxin. While T-2 tetraol was completely ineffective as an inhibitor, DON exhibited minimal inhibitory activity at concentrations above 10×10?4M. The stability of the platelet aggregates formed was significantly reduced in all mycotoxin treated platelets compared to that of the untreated PAF controls. It is suggested that the increased sensitivity of PAF stimulated bovine platelets to the more lipophilic mycotoxins may be related to their more efficient partitioning into the platelet membrane compared to the more hydrophilic compounds.  相似文献   
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