Study on the changes of some physiological factors during osmoregulation of juvenile Persian sturgeons (Acipenser persicus)

Experimental trials of acclimatization of juvenile Persian sturgeon, Acipenser persicus to different salinites of 0,5,10, 15ppt were studied. The juvenile Persian sturgeons in three weight classes (1.5, 3, 5g) have been transfered from freshwater to different concentrations of saline water. Na+, k+, Cl- concentrations of blood serum and the changes in the number and size of chloride cells were measured. Na+ concentration showed an imperceptible trend and K+ concentration had a decreasing one size of changed chloride cells in different salinities were 8.6-13±0.3 μm and their numbers were (25-65±3) in 5 pairs of fillaments. The results revealed that salinity tolerance was increased with the fish size. According to this study, there is a direct relation between the number and size of chloide cells and salinities and time exposure

The effect of Satureja khuzestanica on triglyceride, glucose, creatinine and alkaline phosphatase activity in rat

زمینه و هدف: مرزه یا ساتوریا خوزستانیکا (Satureja khuzestanica) از گیاهان بومی ایران می باشد که به طور گسترده ای در نواحی جنوبی کشور به ویژه استان لرستان وجود دارد و در طب سنتی دارای مصارف پزشکی، از جمله فعالیت ضد درد و عفونت می باشد. در مطالعات قبلی مشاهده گردید که این گیاه باعث کاهش معنی دار وزن در موشهای مورد آزمایش شده است. بر همین اساس بر آن شدیم اثرات دم کرده و اسانس روغنی این گیاه را روی وزن بدن، دریافت غذا و فاکتورهای لیپیدی، قندی، پروتئینی، الکترولیت ها و آنزیم های کبدی در رت بررسی کنیم. روش بررسی: این مطالعه تجربی است که در سال 1382 در مرکز تحقیقات گیاهان دارویی دانشگاه علوم پزشکی لرستان انجام شد. دم کرده گیاه مزبور به مقادیر 75، 150 و 250 میلی گرم بر کیلوگرم از راه خوراکی به مدت سه هفته به ترتیب برای حیوانات در سه گروه تجویز شد و در گروه چهارم، اسانس روغنی گیاه در آب خوراکی به میزانppm 1000 حل و تجویز گردید. در عین حال برای گروه کنترل هیچگونه گیاهی تجویز نشد. وزن حیوانات و میزان دریافت آب و غذای آنها بصورت روزانه ثبت گردید و در پایان 3 هفته فاکتورهای خونی و آنزیم های کبدی در سرم این حیوانات اندازه گیری شد. داده ها با آزمون ANOVA یکطرفه و بدنبال آن آزمون Tukey با یکدیگر مقایسه گردید و در بعضی گروهها که توزیع داده ها نرمال نبود از آزمون من ویتنی استفاده شد. یافته ها: میزان تری گلیسرید سرمی در گروه اسانس روغنی )92/3±15/43 میلی گرم بر دسی لیتر) نسبت به گروه کنترل (03/8±99/89 میلی گرم بر دسی لیتر) تفاوت معنی دار داشت (001/0

Cooling or Warming the Esophagus to Reduce Esophageal Injury During Left Atrial Ablation in the Treatment of Atrial Fibrillation.

Ablation of the left atrium using either radiofrequency (RF) or cryothermal energy is an effective treatment for atrial fibrillation (AF) and is the most frequent type of cardiac ablation procedure performed. Although generally safe, collateral injury to surrounding structures, particularly the esophagus, remains a concern. Cooling or warming the esophagus to counteract the heat from RF ablation, or the cold from cryoablation, is a method that is used to reduce thermal esophageal injury, and there are increasing data to support this approach. This protocol describes the use of a commercially available esophageal temperature management device to cool or warm the esophagus to reduce esophageal injury during left atrial ablation. The temperature management device is powered by standard water-blanket heat exchangers, and is shaped like a standard orogastric tube placed for gastric suctioning and decompression. Water circulates through the device in a closed-loop circuit, transferring heat across the silicone walls of the device, through the esophageal wall. Placement of the device is analogous to the placement of a typical orogastric tube, and temperature is adjusted via the external heat-exchanger console

Turbulence Time Series Data Hole Filling using Karhunen-Loeve and ARIMA methods

Measurements of optical turbulence time series data using unattended instruments over long time intervals inevitably lead to data drop-outs or degraded signals. We present a comparison of methods using both Principal Component Analysis, which is also known as the Karhunen--Loeve decomposition, and ARIMA that seek to correct for these event-induced and mechanically-induced signal drop-outs and degradations. We report on the quality of the correction by examining the Intrinsic Mode Functions generated by Empirical Mode Decomposition. The data studied are optical turbulence parameter time series from a commercial long path length optical anemometer/scintillometer, measured over several hundred metres in outdoor environments.Comment: 8 pages, 9 figures, submitted to ICOLAD 2007, City University, London, U

MiR-155 has a protective role in the development of non-alcoholic hepatosteatosis in mice

Hepatic steatosis is a global epidemic that is thought to contribute to the pathogenesis of type 2 diabetes. MicroRNAs (miRs) are regulators that can functionally integrate a range of metabolic and inflammatory pathways in liver. We aimed to investigate the functional role of miR-155 in hepatic steatosis. Male C57BL/6 wild-type (WT) and miR-155−/− mice were fed either normal chow or high fat diet (HFD) for 6 months then lipid levels, metabolic and inflammatory parameters were assessed in livers and serum of the mice. Mice lacking endogenous miR-155 that were fed HFD for 6 months developed increased hepatic steatosis compared to WT controls. This was associated with increased liver weight and serum VLDL/LDL cholesterol and alanine transaminase (ALT) levels, as well as increased hepatic expression of genes involved in glucose regulation (Pck1, Cebpa), fatty acid uptake (Cd36) and lipid metabolism (Fasn, Fabp4, Lpl, Abcd2, Pla2g7). Using miRNA target prediction algorithms and the microarray transcriptomic profile of miR-155−/− livers, we identified and validated that Nr1h3 (LXRα) as a direct miR-155 target gene that is potentially responsible for the liver phenotype of miR-155−/− mice. Together these data indicate that miR-155 plays a pivotal role regulating lipid metabolism in liver and that its deregulation may lead to hepatic steatosis in patients with diabetes

Importance of source structure on complex organics emission III. Effect of disks around massive protostars

Complex organic molecules are only detected toward a fraction of high-mass protostars. The goal of this work is to investigate whether high-mass disks can explain the lack of methanol emission from some massive protostellar systems. We consider an envelope-only and an envelope-plus-disk model and use RADMC-3D to calculate the methanol emission. High and low millimeter (mm) opacity dust are considered for both models separately and the methanol abundance is parameterized. Viscous heating is included due to the high accretion rates of these objects in the disk. In contrast with low-mass protostars, the presence of a disk does not significantly affect the temperature structure and methanol emission. The shadowing effect of the disk is not as important for high-mass objects and the disk mid-plane is hot because of viscous heating, which is effective due to the high accretion rates. Consistent with observations of infrared absorption lines toward high-mass protostars, we find a vertical temperature inversion, i.e. higher temperatures in the disk mid-plane than the disk surface, at radii < 50au for the models with $L=10^4$ L$_{\odot}$ and large mm opacity dust as long as the envelope mass is >550 M$_{\odot}$. The large observed scatter in methanol emission from massive protostars can be mostly explained toward lower luminosity objects with the envelope-plus-disk models including low and high mm opacity dust. The methanol emission variation toward sources with high luminosities cannot be explained by models with or without a disk. However, the $L/M$ of these objects suggest that they could be associated with hypercompact/ultracompact HII regions. Therefore, the low methanol emission toward the high-luminosity sources can be explained by them hosting an HII region where methanol is absent.Comment: 25 pages, 24 figures, Accepted for publication in A&

Nucleocytoplasmic transport: a thermodynamic mechanism

The nuclear pore supports molecular communication between cytoplasm and nucleus in eukaryotic cells. Selective transport of proteins is mediated by soluble receptors, whose regulation by the small GTPase Ran leads to cargo accumulation in, or depletion from the nucleus, i.e., nuclear import or nuclear export. We consider the operation of this transport system by a combined analytical and experimental approach. Provocative predictions of a simple model were tested using cell-free nuclei reconstituted in Xenopus egg extract, a system well suited to quantitative studies. We found that accumulation capacity is limited, so that introduction of one import cargo leads to egress of another. Clearly, the pore per se does not determine transport directionality. Moreover, different cargo reach a similar ratio of nuclear to cytoplasmic concentration in steady-state. The model shows that this ratio should in fact be independent of the receptor-cargo affinity, though kinetics may be strongly influenced. Numerical conservation of the system components highlights a conflict between the observations and the popular concept of transport cycles. We suggest that chemical partitioning provides a framework to understand the capacity to generate concentration gradients by equilibration of the receptor-cargo intermediary.Comment: in press at HFSP Journal, vol 3 16 text pages, 1 table, 4 figures, plus Supplementary Material include