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681.
The present study reports the convenient synthesis, spectroscopic characterization, bio‐assays and computational evaluation of a novel series of N‐acyl‐1H‐imidazole‐1‐carbothioamides. The screened derivatives displayed excellent antioxidant activity, moderate antibacterial and antifungal potential. The screened derivatives were found to be highly biocompatible against hRBCs. Molecular docking ascertained the mechanism and mode of action towards the molecular target delineating that ligands and complexes were stabilized at the active site by electrostatic and hydrophobic forces in accordance to the corresponding experimental results. Docking simulation provided additional information about the possibilities of inhibitory potential of the compounds against RNA. Computational evaluation predicted that N‐acyl‐1H‐imidazole‐1‐carbothioamides 5c and 5g can serve as potential surrogates for hit to lead generation and design of novel antioxidant and antibacterial agents.  相似文献   
682.
The study was devised to prepare berberine nanoparticles by anti-solvent precipitation method and were assessed for their hepatoprotective effect in Male Sprague-Dawley rats against carbon tetrachloride. The pharmacokinetic parameters of the prepared nanoparticles and berberine were evaluated in rabbits. Histopathological studies and blood biochemical analyses were carried out to evaluate the role of both forms of berberine in the experimental animals. Substantial improvement in the liver function test enzymes levels and liver histopathology were achieved in the animals treated with berberine nanoparticles in comparison to the unprocessed berberine whereas, pharmacokinetic parameters for nanoform of berberine were about 3.97 and 3.88 folds higher than that of the unprocessed berberine. The study revealed that the reduction of berberine particle size to nano range improved pharmacokinetic parameters in rabbits. The nano berberine provided better liver protection in experimental rats and high berberine blood concentration. Thus, better hepatoprotective and pharmacokinetics effects were observed for the nano form in comparison to unprocessed form.  相似文献   
683.
Changes in plasma glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT), triiodothyronine (T3), and thyroxin (T4) of male rats, following 8?weeks of administration of different concentrations of elemental iron (EI), sodium iron ethylenediaminetetraacetate (NaFeEDTA), zinc sulfate (ZnSO(4)), and zinc oxide (ZnO) in whole wheat flour were investigated. Liver enzymes and thyroid hormones were determined using colorimetric methods and enzyme immune assay, respectively. Ingestion of fortified diets by the male rats did not show a marked effect on GOT and GPT, the exception being NaFeEDTA fed alone and EI with ZnO-fortified diets indicating a significant (p?相似文献   
684.
The growth pattern of the endemic Neretvan roach, Rutilus basak from the Hutovo Blato wetlands was analyzed. A total of 441 specimens ranging from 6.0 to 21.7 cm TL were obtained by electro fishing between December 2007 and November 2008. The male:female ratio for all fish combined was 0.34 : 1.00 but changed across length classes. The spawning period extended from February to April, with a peak in the first half of March. Maximum observed age was 10 years. Predominance of age classes 1–5 in the catch (77.0% of individuals) was noted. The length–weight relationship showed a positive allometric growth (b = 3.321; R2 = 0.957). Parameters of the von Bertalanffy equation were: L = 20.201 cm; K = 0.257 per year; t0 = ?1.554 year; R2 = 0.977. This study revealed that R. basak invests energy in reproduction rather than in body size and thus has a relatively fast growth, short life span and precocious maturity. Moreover, elementary biological population parameters are provided that can be used for conservation purposes.  相似文献   
685.
A number of dermal toxicological studies using TiO2 nanoparticles exist which are based on the study of various animal models like mice, rabbits etc. However, a well-defined study is lacking on the dermal toxic effects of TiO2 nanoparticles on rats, which are the appropriate model for systemic absorption study of nanoparticles. Furthermore, toxicity of TiO2 nanoparticles varies widely depending upon the size, concentration, crystallinity, synthesis method etc. This study was conducted to synthesize TiO2 nanoparticles of different sizes (∼15 to ∼30 nm) by aqueous method, thereby evaluating the concentration-dependent toxicological effects of the ∼20-nm sized nanoparticles on Wistar rats. Characterization of the particles was done by transmission electron microscope, dynamic light scattering instrument, X-ray diffractrometer, and ultraviolet spectrophotometer. The toxicity study was conducted for 14 days (acute), and it is observed that TiO2 nanoparticles (∼20 nm) at a concentration of 42 mg/kg, when applied topically showed toxicity on rat skin at the biochemical level. However, the histopathological studies did not show any observable effects at tissue level. Our data suggest that well-crystallized spherical-shaped ∼20 nm anatase TiO2 nanoparticles synthesized in aqueous medium can induce concentration-dependent biochemical alteration in rat skin during short-term exposure.  相似文献   
686.
Essential oils are complex mixtures of odorous and volatile compounds derived from secondary plant metabolism. They can be isolated from many plants by mechanical pressing or hydro- and steam-distillation and are known to induce a wide range of biological effects through their antibacterial, antifungal, cytotoxic, antioxidant and antimutagenic activities. In order to explore their beneficial properties on human skin cells, we investigated the effects of an essential oil from rosewood Aniba rosaeodora (REO) on the human epidermoid carcinoma cell line A431, on immortal HaCaT cells thought to represent an early stage of skin carcinogenesis, on transformed normal HEK001 keratinocytes and on primary normal NHEK keratinocytes. In a defined range of concentrations, REO selectively killed A431 and HaCaT cells. The same treatments had only a minor cytotoxic effect on HEK001 and NHEK cells. Preferentially in A431 and HaCaT cells, REO triggered the production of reactive oxygen species, induced depolarization of the mitochondrial membrane and caused caspase-dependent cell death characterized by phosphatidylserine externalization, an early marker of apoptosis. Both intrinsic and extrinsic apoptotic pathways were implicated in REO-induced cell death. The identification of selective induction of apoptosis in precancerous and cancerous skin cells by REO highlights the potential anticancer activity of this essential oil.  相似文献   
687.
688.
Telomere Position Effect (TPE) is governed by strong repression signals emitted by telomeres via the Sir2/3/4 Histone Deacetylase complex. These signals are then relayed by weak proto-silencers residing in the subtelomeric core X and Y' elements. Subtelomeres also contain Sub-Telomeric Anti-silencing Regions (STARs). In this study we have prepared telomeres built of different combinations of core X, Y' and STARs and have analyzed them in strains lacking Histone-Acetyltransferase genes as well as in cdc6-1 and Δrif1 strains. We show that core X and Y' dramatically reduce both positive and negative variations in TPE, that are caused by these mutations. We also show that the deletion of Histone-Acetyltransferase genes reduce the silencing activity of an ACS proto-silencer, but also reduce the anti-silencing activity of a STAR. We postulate that core X and Y' act as epigenetic "cushioning" cis-elements.  相似文献   
689.
Although most mtDNA lineages observed in contemporary Icelanders can be traced to neighboring populations in the British Isles and Scandinavia, one may have a more distant origin. This lineage belongs to haplogroup C1, one of a handful that was involved in the settlement of the Americas around 14,000 years ago. Contrary to an initial assumption that this lineage was a recent arrival, preliminary genealogical analyses revealed that the C1 lineage was present in the Icelandic mtDNA pool at least 300 years ago. This raised the intriguing possibility that the Icelandic C1 lineage could be traced to Viking voyages to the Americas that commenced in the 10th century. In an attempt to shed further light on the entry date of the C1 lineage into the Icelandic mtDNA pool and its geographical origin, we used the deCODE Genetics genealogical database to identify additional matrilineal ancestors that carry the C1 lineage and then sequenced the complete mtDNA genome of 11 contemporary C1 carriers from four different matrilines. Our results indicate a latest possible arrival date in Iceland of just prior to 1700 and a likely arrival date centuries earlier. Most surprisingly, we demonstrate that the Icelandic C1 lineage does not belong to any of the four known Native American (C1b, C1c, and C1d) or Asian (C1a) subclades of haplogroup C1. Rather, it is presently the only known member of a new subclade, C1e. While a Native American origin seems most likely for C1e, an Asian or European origin cannot be ruled out.  相似文献   
690.
The aim of this article was to investigate the prevalence of diabetes mellitus and abnormal lipid status with selected anthropometric variables in a sample of hospitalized coronary heart disease (CHD) patients in Croatia (N = 1,298). Prevalence of diabetes mellitus was 31.6% (statistically significantly more frequent in women, 35.7% vs. 30.0%), while prevalences of increased total cholesterol were 72.0%, decreased HDL-cholesterol 42.6% (statistically significantly more frequent in women, 50.2% vs. 39.6%), increased LDL-cholesterol 72.3% and increased triglycerides 51.5%. Reported data on prevalences of diabetes mellitus can be somewhat reassuring (a decrease in its prevalence compared to data from 2006, but they still signal a situation which is a lot worse than in 2002 and 2003); the trend of rising prevalences of dyslipidaemic cardiovascular risk factors must be a cause for an alarm, furthermore as today's preventive and treatment measures in cardiology, both primary and secondary, are strongly focused on dyslipidaemias.  相似文献   
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