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181.
The present study examined the protective effects of vitamin E against aluminum-induced neurotoxicity in rats. Wistar rats were given daily aluminum via their drinking water containing 1600 mg/liter aluminum chloride for six weeks. Aluminum induced a significant increase in lipid peroxidation (LPO) in hippocampus and frontal cortex. Furthermore, aluminum caused marked elevation in the levels of the glial markers (glial fibrillary acidic protein (GFAP) and S100B) and proinflammatory cytokines (TNF-alpha and IL-1beta) in both brain areas. Vitamin E treatment reduced the contents of glial markers and cytokines and the levels of LPO. In conclusion, this study demonstrates that vitamin E ameliorates glial activation and reduces release of proinflammatory cytokines induced by aluminum.  相似文献   
182.
Journal of Plant Growth Regulation - Considering the unfavorable impacts of methyl viologen-induced oxidative stress (MV1-2, 50 and 500 µM) on growth, gas exchange (intercellular CO2...  相似文献   
183.
Abstract

Small molecule diffusion into Iota-Carrageenan gel was studied by using steady-state fluorescence (SSF) technique. Pyranine, dissolved in water was used as fluorescence probe. Fluorescence emission intensity, Ip, and scattered light intensity, Isc, were monitored to study diffusion and swelling processes at various temperatures respectively. Fickian and Li-Tanaka models were elaborated to produce diffusion, D, and collective diffusion, D 0, coefficients. Diffusion and swelling activation energies were also obtained and found to be 20.5 kj mol?1 and 28.2 kj mol?1, respectively.  相似文献   
184.
Abstract

Lipases are one of the most important catalysts for several industries such as detergent, dairy, and textile industry due to their bio-catalytic ability in aqueous and non-aqueous media. Stability to extreme conditions is an important property since it makes enzymes suitable to several industrial processes. In this study, lipase producing soil bacteria were screened and identified with 16S rDNA sequencing. A new hyper-thermophilic lipase named as Bacillus subtilis LP2 isolate was partially purified by ammonium sulphate precipitation with 17.8-fold purification and 583?U/mg specific activity. Maximum activity was exhibited at pH 7 and 80?°C with the substrate tween 80?KM and Vmax values were calculated as 18.3?mM and 680?U/mg with a catalytic efficiency (kcat/KM) of 307?s?1M?1. These results indicate that lipase from Bacillus subtilis LP2 can be a valuable candidate for industrial applications such as organic synthesis and fats and oils industry due to their efficient catalysis in higher temperatures.  相似文献   
185.
Extensive use of Pesticides in agriculture and its surface runoff in river water is a major environmental concern. The present study evaluated the phytoremediation potential of Eichornia crassipes, Pistia strateotes and algae (Chaetomorpha sutoria, Sirogonium sticticum and Zygnema sp.) for organochlorine and pyrethroid pesticides. Water and plant samples were extracted by liquid phase and solid phase extraction respectively and analyzed by high-performance liquid chromatography. Eleven treatments (T1–T11) with and without plants were used for phytoremediation of organochlorine and pyrethroid pesticides. During the experiment, P. strateotes, E. crassipes and algae (C. sutoria, S. sticticum and Zygnema sp.) showed the highest removal efficiency with 62 (71% root, 29% shoot), 60 (67% root, 33% shoot), and 58% respectively for organochlorine and 76 (76% root, 24% shoot), 68 (69% root, 31% shoot), and 70% respectively for pyrethroids for the respective aquatic plants. Dissipation rate constant of treatments with plants (T2, T3, T5, T6, T8, and T9) was significantly higher (p < 0.05) as compared to that of treatments without plants (T10 and T11, control) for both organochlorine and pyrethroid. The bioconcentration factor of pyrethroid treatments (T3, T6, and T9) was significantly higher (p < 0.05) as compared to that of organochlorine treatments (T2, T5 and T8). The removal efficiency of E. crassipes, P. strateotes and algae (C. sutoria, S. sticticum and Zygnema sp.) for pyrethroids was significantly higher (p < 0.01) as compared to that of organochlorine.  相似文献   
186.
Biomechanics and Modeling in Mechanobiology - Renal cystogenesis is the pathological hallmark of autosomal dominant polycystic kidney disease, caused by PKD1 and PKD2 mutations. The formation of...  相似文献   
187.
Granulocyte-colony stimulating factor (G-CSF) has become the most effective agent supporting hematopoietic stem cell transplantation (HSCT). The cognate interaction between G-CSF and its specific receptor, G-CSFR, induces the mobilization of HSCs and increases their pool in the peripheral blood. G-CSFR has a highly conserved structure which may be functionally modulated by the presence of missense single nucleotide polymorphisms (SNPs). In this study, we asked whether the missense SNPs in G-CSFR could affect the response to G-CSF in HSCT patients and donors. Here, for the first time, G-CSFR missense SNPs were screened and minor allele frequencies were determined in a specific population with Turkish racial background. Five (rs3917991, rs3918001, rs3918018, rs3918019, and rs146617729) out of 16 missense SNPs screened were determined with minor allele frequencies lower than 0.04. Subsequent association analyses indicated potential impact of rs3918001, rs3918018, and rs3918019 minor alleles on peripheral blood CD34+ cell enrichment. Although their frequency is rather low, certain missense SNPs, especially which are placed in the conserved regions of G-CSFR may possess the capacity to influence the response to G-CSF treatment.  相似文献   
188.
189.
This study aimed to parameterize the effects of body and meal sizes on the gastric evacuation (GE) of farmed Russian sturgeon (Acipenser gueldenstaedtii) fed on live food (whiting fish) or commercial pellets. The radiography technique was used to monitor the evacuation of food from the stomach into the intestine at postprandial time. Acipenser gueldenstaedtii of different body sizes (total length ranged 82–105 cm) were fed on meal sizes ranged from 23 to 72 g composed of either live food or commercial pellets (had a 20% of BaSO4 as a radiopaque material). The square root model was found to adequality describe the process of GE in A. gueldenstaedtii independently of meal type and size. The effects of fish size on GER was described by simple power model and can be summarized by , where ρL was 0.000053 for live food and 0.000062 for commercial pellets (estimated from combined GE data), St is stomach contents (g), L is fish total length (cm) and t is time (h). The results of this study will provide a useful tool to estimate the stomach fullness of A. gueldenstaedtii at postprandial time t. Such information should assess the feeding strategy to minimize feed wastage and optimize the fish growth.  相似文献   
190.
The denitrification process was incorporated into the IWA Anaerobic Digestion Model No. 1 (ADM1) in order to account for the effect of denitrification on the methanogenic fermentation process. The model was calibrated and optimized using previously published experimental data and kinetic parameter values obtained with a mixed, mesophilic (35°C) methanogenic culture. Model simulations were used to predict the effect of nitrate reduction on the methanogenic fermentation process in batch, semi‐continuous, and continuous flow reactors experiencing operational changes and/or system disturbances. The extended model clearly revealed the importance of substrate competition between denitrifiers and non‐denitrifiers as well as the impact of N‐oxide inhibition on process interactions between fermentation, methanogenesis, and denitrification. Biotechnol. Bioeng. 2010;105: 98–108. © 2009 Wiley Periodicals, Inc.  相似文献   
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