Molecular effects of leptin on peroxisome proliferator activated receptor gamma (PPAR-γ) mRNA expression in rat's adipose and liver tissue.

Leptin is a 16-kDa peptide hormone secreted by adipose tissue that participates in the regulation of energy homeostasis. The aim of this study was to determine the effect of leptin injection on mRNA expression of peroxisome proliferator-activated receptor gamma (PPAR-γ) and comparison of PPAR-γ mRNA expression in rat's adipose and liver tissue. Twenty adult male rats were divided into the following groups: Group 1asa control (n=10) that did not receive any treatment. Group 2as a treatment (n=10) that received leptin (30 µg / kg BW) intraperitoneally (ip) for two successive days. Blood samples were taken before and one day after second leptin injection for triglyceride (TG), Free Fatty Acid (FFA), HLD-cholesterol, and LDL-cholesterol measurement. Total RNA was extractedfrom the adipose tissue and liver tissues of rats.  Adipose and liver tissue cells' cDNA was synthesized to characterize the expression of PPAR-γ. Gene expression of PPAR-γ mRNA was tested by RT- PCR technique. Results show leptin decreases expression of PPAR-γ on rat. Low levels of PPAR-γ mRNA were detected in adipose and liver tissues of treatment rats in comparison to control group. In treatment group, the level of PPAR-γ mRNA in liver tissue was very lower than the adipose tissue. The levels of HDL and FFA in treatment rats were increased whereas serum levels TG, VLDL and LDL were not changed. It is concluded that leptin signal with suppressing of PPAR-γ mRNA expression in rat's adipose and liver tissues can result in lipolysis instead of lipogenesis.

Isolation and in silico functional analysis of MtATP6, a 6-kDa subunit of mitochondrial F1F0-ATP synthase, in response to abiotic stress.

Mitochondrial F(1)F(0)-ATP synthase is a key enzymatic complex of energy metabolism that provides ATP for the cell. Subunits of this enzyme over-express under stress conditions. Little is known about the structure and regulatory mechanism of the F(0) portion of this enzyme. We isolated the full-length coding sequence of the RMtATP6 gene from rice and wheat, and partial sequences from Aegilops crassa and Triticum monococcum (Poaceae). We found that the sequence of rice RMtATP6 is 1965 bp long and contains two exons and one intron in 3'-UTR. Then, we analyzed the 2000-bp upstream region of the initiation codon ATG of the RMtATP6 and AtMtATP6, as promoter. The RMtATP6 coding sequence was found to be much conserved in the different plant species, possibly because of its key role under stress conditions. Promoter analysis demonstrated that RMtATP6 and AtMtATP6 include cis-acting elements such as ABRE, MYC/MYB, GT element in the upstream region, which respond to abscisic acid stress hormone and might show vital its roles in biotic and abiotic tolerance as an early-stress responsive gene. A mitochondrial signal peptide of 30 amino acids in length and an N-terminal cleavage site between amino acids 20 and 21 were discovered in RMtATP6. In addition, we found a transmembrane domain with an alpha helix structure that possibly passed through the mitochondrial inner membrane and established the 6-kDa subunit in the F(0) portion of the enzyme complex. Apparently, under stress conditions, with increasing ATP consumption by the cell, the 6-kDa subunit accumulates; by switching on F(1)F(0)-ATP synthase it provides additional energy needed for cell homeostasis.

Electrostatic subframing and compressive-sensing video in transmission electron microscopy.

We present kilohertz-scale video capture rates in a transmission electron microscope, using a camera normally limited to hertz-scale acquisition. An electrostatic deflector rasters a discrete array of images over a large camera, decoupling the acquisition time per subframe from the camera readout time. Total-variation regularization allows features in overlapping subframes to be correctly placed in each frame. Moreover, the system can be operated in a compressive-sensing video mode, whereby the deflections are performed in a known pseudorandom sequence. Compressive sensing in effect performs data compression before the readout, such that the video resulting from the reconstruction can have substantially more total pixels than that were read from the camera. This allows, for example, 100 frames of video to be encoded and reconstructed using only 15 captured subframes in a single camera exposure. We demonstrate experimental tests including laser-driven melting/dewetting, sintering, and grain coarsening of nanostructured gold, with reconstructed video rates up to 10 kHz. The results exemplify the power of the technique by showing that it can be used to study the fundamentally different temporal behavior for the three different physical processes. Both sintering and coarsening exhibited self-limiting behavior, whereby the process essentially stopped even while the heating laser continued to strike the material. We attribute this to changes in laser absorption and to processes inherent to thin-film coarsening. In contrast, the dewetting proceeded at a relatively uniform rate after an initial incubation time consistent with the establishment of a steady-state temperature profile.

Effect of magnesium sulfate on extubation time and acute pain in coronary artery bypass surgery.

BACKGROUND: Post-operative pain control is one of the greatest concerns for both physicians and patients. In this study, the effect of magnesium sulfate (MgSO(4)) solution infusion on post-operative pain scores and extubation time in patients undergoing elective coronary artery bypass graft (CABG) surgeries was assessed. METHODS: In a double-blind, randomized, placebo-controlled clinical trial, 218 patients scheduled for elective CABG were selected and randomly assigned to two groups. After matching inclusion and exclusion criteria for the patients, intravenous MgSO(4) was administered intraoperatively for one group and placebo to the second group. Except for this, all the cases were similar regarding anesthesia and surgery. RESULTS: The MgSO(4) patients were extubated sooner compared with the placebo group. Pain scores reported by the group who received MgSO(4) were less at the 6th, 12th, 18th and 24th hours after the operation; also, they needed less morphine sulfate during this period. CONCLUSION: The results demonstrated a significantly shortened post-operative time for extubation and reduced acute post-operative pain scores by intravenous MgSO(4) infusion during elective CABG surgery.