Differential regulation of Ota and Otb, two primary glycine betaine transporters in the methanogenic archaeon Methanosarcina mazei go1

Methanogenic archaea accumulate glycine betaine in response to hypersalinity, but the regulation of proteins involved, their mechanism of activation and regulation of the corresponding genes are largely unknown. Methanosarcina mazei differs from most other methanoarchaea in having two gene clusters both encoding a potential glycine betaine transporter, Ota and Otb. Western blot as well as quantitative real-time PCR revealed that Otb is not regulated by osmolarity. On the other hand, cellular levels of Ota increased with increasing salt concentrations. A maximum was reached at 300-500 m M NaCl. Ota concentrations reached a maximum 4 h after an osmotic upshock. Hyperosmolarity also caused an increase in cellular Ota concentrations. In addition to osmolarity Ota expression was regulated by the growth phase. Expression of Ota as well as transport of betaine was downregulated in the presence of glycine betaine. Copyright (c) 2007 S. Karger AG, Basel

Long-Term Lipid Effects of Pioglitazone by Baseline Anti-Hyperglycemia Medication Therapy and Statin Use from the PROactive Experience (PROactive 14)

Studies have shown that pioglitazone treatment in patients with type 2 diabetes mellitus can improve parameters of diabetic dyslipidemia. The aim of this study was to examine the effect of pioglitazone on triglycerides, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol levels in patients from the Prospective Pioglitazone Clinical Trial in Macrovascular Events (PROactive) to determine whether pioglitazone-induced lipid effects were altered by different baseline antihyperglycemia medication or statin use. PROactive was a long-term, randomized, double-blind, cardiovascular outcomes study in patients with type 2 diabetes at high cardiovascular risk who had pioglitazone or placebo added to existing treatment. The present post hoc study analyzed lipid results from patients who received different baseline antihyperglycemia regimens and the presence or absence of baseline statin use. Independent of antihyperglycemia medication and statin use, triglyceride levels decreased in all subgroups treated with pioglitazone (-9.9% to -12.3%), whereas little change was observed in placebo groups. High-density lipoprotein cholesterol increased nearly twice as much with pioglitazone (18.1% to 20.3%) as with placebo (8.1% to 11.8%) across all subgroups. Low-density lipoprotein cholesterol increased moderately with pioglitazone (5.2% to 9.6%) compared with placebo (3.3% to 7.6%) (placebo-adjusted range 1.11% to 4.37%). In conclusion, long-term pioglitazone therapy led to durable improvements in triglyceride and high-density lipoprotein cholesterol levels, irrespective of baseline antihyperglycemia therapy or statin use. (C) 2009 Published by Elsevier Inc. (Am J Cardiol 2009;104:234-239

Nanostructured LiMPO

Nanostructured materials are considered to be strong candidates for fundamental advances in efficient storage and/or conversion. In nanostructured materials transport kinetics and surface processes play determining roles. This work describes recent developments in the synthesis and characterization of composites which consist of lithium metal phosphates (LiMPO4, M = Fe, Mn, Co, Ni) coated on nanostructured carbon supports (unordered nanofibers, foams). The composites have been prepared by coating the carbon structures in aqueous (or polyols) solutions containing lithium, metal ions and phosphates. After drying out, the composites have been thermally treated at different temperatures (between 600-780°C) for 5-12 hours under nitrogen. The formation of the olivine structured phase was confirmed by the X-ray diffraction analysis on powders prepared under very similar conditions. The surface investigation revealed the formation of an homogeneous coating of the olivine phase on the carbon structures. The electrochemical performance on the composites showed a dramatic improvement of the discharge specific capacity (measured at a discharge rate of C/25 and room temperature) compared to the prepared powders. The delivered values were 105 mAhg-1 for M = Fe, 100 mAhg-1 for M = Co, 70 mAhg-1 for M = Mn and 30 mAhg-1 for M = Ni respectively

Nanostructured LiMPO4 (M = Fe, Mn, Co, Ni) – carbon composites as cathode materials for Li-ion battery

Nanostructured materials are considered to be strong candidates for fundamental advances in efficient storage and/or conversion. In nanostructured materials transport kinetics and surface processes play determining roles. This work describes recent developments in the synthesis and characterization of composites which consist of lithium metal phosphates (LiMPO4, M = Fe, Mn, Co, Ni) coated on nanostructured carbon supports (unordered nanofibers, foams). The composites have been prepared by coating the carbon structures in aqueous (or polyols) solutions containing lithium, metal ions and phosphates. After drying out, the composites have been thermally treated at different temperatures (between 600-780°C) for 5-12 hours under nitrogen. The formation of the olivine structured phase was confirmed by the X-ray diffraction analysis on powders prepared under very similar conditions. The surface investigation revealed the formation of an homogeneous coating of the olivine phase on the carbon structures. The electrochemical performance on the composites showed a dramatic improvement of the discharge specific capacity (measured at a discharge rate of C/25 and room temperature) compared to the prepared powders. The delivered values were 105 mAhg-1 for M = Fe, 100 mAhg-1 for M = Co, 70 mAhg-1 for M = Mn and 30 mAhg-1 for M = Ni respectively

Observational follow-up of the PROactive study: a 6-year update

AimsThe PROactive study investigated pioglitazone for secondary prevention of macrovascular events in type 2 diabetes mellitus. Pioglitazone showed a 10% (non-significant) relative risk (RR) reduction for the primary composite endpoint and a significant 16% reduction for the main secondary endpoint (death, myocardial infarction, stroke) after a mean 34.5months. There was no difference in cumulative malignancy incidence, but an imbalance in bladder malignancies (pioglitazone 14, placebo 5). We present a pre-specified 6-year interim analysis of a 10-year observational follow-up. MethodsAny patient completing PROactive was eligible. No study treatments were provided. A Cox proportional hazard model compared non-adjudicated macrovascular events (same endpoints as PROactive excluding acute coronary syndrome) based on original randomization. Malignancies were compared using conventional RR ratios. ResultsOf 5238 randomized patients, 3599 (74%) entered the follow-up. For the follow-up (mean 5.8years) or combined double-blind and follow-up periods (9.5years, mean 8.7), there were no statistically significant differences in primary or main secondary endpoints. For the combined period, a similar percentage of patients had any diagnosed malignancy (RR=1.05, 95% CI [0.89, 1.24]) or bladder malignancy (RR=1.06, 95% CI [0.59, 1.89]) in the pioglitazone and placebo groups. There were fewer cases of bladder malignancy with pioglitazone (15 [0.6%] vs. 19 [0.7%] for placebo) for the combined period when events diagnosed in the first 365days were excluded, and fewer cases for the follow-up period alone (10 [0.5%] vs. 17 [1.0%] for placebo). Further analyses of pioglitazone use (including use during follow-up) found no significant difference in bladder malignancies between any and no pioglitazone use for the combined period. ConclusionsThese data suggest that improved macrovascular outcomes seen with pioglitazone subside without continued pioglitazone treatment. The double-blind period bladder cancer imbalance did not persist in follow-up

Power gain up to gigahertz frequencies in three-terminal nanojunctions at room temperature

Direct current and alternating current characteristics of three-terminal nanojunctions (TTJs) are studied at room temperature. The TTJs are based on a modulation-doped GaAs/AlGaAs heterostructure and were structured by applying mask techniques and wet chemical etching. Devices with lateral dimensions of a few tens of nanometers and with narrow gold contacts were fabricated and transistor characteristics with maximum transconductance values exceeding 100 mu A/V are demonstrated. By analyzing the scattering parameters of the TTJs, power gain up to 1.5 GHz is observed. This gigahertz amplification is related to the implemented narrow gold contacts which control the quantum capacitance of the electron reservoirs.</p

Effects of pioglitazone on bone in postmenopausal women with impaired fasting glucose or impaired glucose tolerance: A randomized, double-Blind, placebo-controlled study

Context: Meta-analyses of clinical studies have suggested an increased incidence of peripheral fractures in postmenopausal women with type 2 diabetes mellitus taking pioglitazone. The mechanism behind this apparent increase is unknown. Objective: The objective of the study was to examine the effects of pioglitazone on bone mineral density (BMD) and turnover. Design and Setting: Twenty-five sites (in the United States) enrolled participants in this randomized, double-blind, placebo-controlled study. Participants: Postmenopausal women (n = 156) with impaired fasting glucose or impaired glucose tolerance participated in the study. Interventions: The intervention consisted of pioglitazone 30 mg/d (n = 78) or placebo (n = 78), increased to 45 mg/d after 1 month, for 12 months of treatment total, followed by 6 months of washout/follow-up. Main Outcome Measures: Percentage changes from baseline to month 12 and from month 12 to month18 in BMD in total proximal femur (primary end point), total body, femoral neck, lumbar spine, and radius were measured. Results: Least squares mean changes from baseline to month 12 in total proximal femur BMD were −0.69% for pioglitazone and −0.14% for placebo (P = .170). No statistically significant between-group differences were observed for any BMD or bone remodeling marker end point. We observed improved glycemic control and insulin sensitivity with pioglitazone treatment. In addition, pioglitazone appeared to increase body fat, which may affect bone density measurements, especially in the lumbar spine. One pioglitazone-treated and three placebo-treated women experienced confirmed fractures. Over 18 months, one pioglitazone-treated (1.3%) and eight placebo-treated women (10.3%) developed overt type 2 diabetes mellitus. The pattern and incidence of adverse events with pioglitazone were consistent with clinical experience with thiazolidinediones. Conclusions: Maximal-dose pioglitazone had no effects on BMD or bone turnover, while improving glycemic control as expected, in postmenopausal women with impaired fasting glucose or impaired glucose tolerance