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21.
Human and animal exposure demonstrates that uranium is nephrotoxic. However, attempts to reduce it were not found suitable for clinical use. Dietary fish oil (FO) enriched in ω-3 fatty acids reduces the severity of cardiovascular and renal diseases. Present study investigates the protective effect of FO on uranyl nitrate (UN)-induced renal damage. Rats prefed with experimental diets for 15 days, given single nephrotoxic dose of UN (0.5 mg/kg body weight) intraperitoneally. After 5 d of UN treatment, serum/urine parameters, enzymes of carbohydrate metabolism, brush border membrane (BBM), oxidative stress and phosphate transport were analyzed in rat kidney. UN nephrotoxicity was characterized by increased serum creatinine and blood urea nitrogen. UN increased the activity of lactate dehydrogenase and NADP-malic enzyme whereas decreased malate, isocitrate and glucose-6-phophate dehydrogenases; glucose-6-phophatase, fructose-1, 6-bisphosphatase and BBM enzyme activities. UN caused oxidant/antioxidant imbalances as reflected by increased lipid peroxidation, activities of superoxide dismutase, glutathione peroxidase and decreased catalase activity. Feeding FO alone increased activities of enzymes of glucose metabolism, BBM, oxidative stress and Pi transport. UN-elicited alterations were prevented by FO feeding. However, corn oil had no such effects and was not similarly effective. In conclusion, FO appears to protect against UN-induced nephrotoxicity by improving energy metabolism and antioxidant defense mechanism.  相似文献   
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<正>Ebola virus disease has caused havoc in West Africa,with 11,162deaths and more than 27,181 cases(as of May 31,2015)being reported since the virus emerged in early2014 in Guinea.The maximum number of cases has been reported in Sierra Leone(12,827),while most of the reported deaths have occurred in Liberia(4,806),according to the Center for Disease Control and  相似文献   
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Lectin-like molecules and their receptors are cell surface molecules that have been shown to play a role in either facilitating infection or serving as transporters of HIV/SIV in vivo. The role of these lectin-like molecules in the pathogenesis of HIV/SIV infection continues to be defined. In efforts to gain further insight on the potential role of these lectin-like molecules, our laboratory generated monoclonal antibodies (mAb) against the human analogs of rhesus macaque CD200, CD200R and Mincle, since the rhesus macaques are accepted as the most reliable animal model to study human HIV infection. The characterization of the cell lineages from the blood and various tissues of rhesus macaques that express these lectin-like molecules are described herein. Among the mononuclear cells, the cells of the myeloid lineage of rhesus macaques are the predominant cell lineages that express readily detectable levels of CD200, CD200R and Mincle that is similar to the expression of Siglec-1 and Siglec-3 reported by our laboratory earlier. Subset analysis revealed that a higher frequency of the CD14+/CD16- subset from normal rhesus macaques express CD200, CD200R and Mincle. Differences in the frequencies and density of expression of these molecules by the gated population of CD14+ cells from various tissues are noted with PBMC and bone marrow expressing the highest and the mononuclear cells isolated from the colon and ileum expressing the lowest levels. While a significant frequency of pDCs and mDCs express Siglec-1/Siglec-3, a much lower frequency expresses CD200, CD200R and Mincle in PBMCs from rhesus macaques. The mAb against CD200 and CD200R but not Mincle appear to inhibit the infection of macrophage tropic SIV/SHIV in vitro. We conclude that these mAbs may have potential to be used as adjunctive therapeutic agents to control/inhibit SIV/HIV infection.  相似文献   
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Plasma membrane is a multifunctional structure that acts as the initial barrier against infection by intracellular pathogens. The productive HIV-1 infection depends upon the initial interaction of virus and host plasma membrane. Immune cells such as CD4 + T cells and macrophages contain essential cell surface receptors and molecules such as CD4, CXCR4, CCR5 and lipid raft components that facilitate HIV-1 entry. From plasma membrane HIV-1 activates signaling pathways that prepare the grounds for viral replication. Through viral proteins HIV-1 hijacks host plasma membrane receptors such as Fas, TNFRs and DR4/DR5, which results in immune evasion and apoptosis both in infected and uninfected bystander cells. These events are hallmark in HIV-1 pathogenesis that leads towards AIDS. The interplay between HIV-1 and plasma membrane signaling has much to offer in terms of viral fitness and pathogenicity, and a better understanding of this interplay may lead to development of new therapeutic approaches. This article is part of a Special Issue entitled: Viral Membrane Proteins — Channels for Cellular Networking.  相似文献   
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The present study is concerned with the isolation and screening of different strains of Aspergillus oryzae for the production of alpha amylase. Ninety strains were isolated from soil and tested for the production of alpha amylase in shake flasks. Of all the strains tested, Aspergillus oryzae GCB-32 and Aspergillus oryzae GCB-35 gave maximum production of alpha amylase. Different culture media were screened for the production of alpha amylase by these two strains. M1 medium containing starch, yeast extract, NH4Cl, MgSO4·7H2O and CaCl2 gave the maximum production of alpha amylase by both the strains Aspergillus oryzae GCB-32 and Aspergillus oryzae GCB-35.Kinetic analysis revealed that the values of product yield coefficient(Yp/x) and specific product yield coefficient(qp) were found highly significant(p≤0.05) when medium M1 was used for the enzyme production.  相似文献   
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分别在2005年和2006年的5、6月份,在Kamalpur和Hunterpara茶园、孟加拉西部以及印度地区对一种昆虫致病真菌球孢白僵菌对油桐尺蛾Buzura (=Biston) suppressaria Guen.的生物效力进行了评估。以农场主常用的化学杀虫剂40% SP灭多虫和25% EC氯氰菊酯作为标准检测物。试验中球孢白僵菌浓度为1.50 g,2.00 g和2.5 g/lit. of water;灭多虫和氯氰菊酯浓度分别为0.75 mL,1.00 mL和1.50 mL,和0.50 mL,1.00 mL和1.50 mL/lit. of water。在喷洒2.5 g/lit. of water 球孢白僵菌3天后,Kamalpur和Hunterpara茶园中油桐尺蛾种群个体数分别降低了88.00%和84.00%。死的毛虫变成黑色,垂悬在叶片上。并且发现球孢白僵菌的杀虫活性与高剂量的灭多虫和氯氰菊酯的相当。  相似文献   
28.
An acid-buffering bioadhesive vaginal tablet was developed for the treatment of genitourinary tract infections. From the bioadhesion experiment and release studies it was found that polycarbophil and sodium carboxymethylcellulose is a good combination for an acid-buffering bioadhesive vaginal tablet. Sodium monocitrate was used as a buffering agent to provide acidic pH (4.4), which is an attribute of a healthy vagina. The effervescent mixture (citric acid and sodium bicarbonate) along with a superdisintegrant (Ac-Di-sol) was used to enhance the swellability of the bioadhesive tablet. The drugs clotrimazole (antifungal) and metronidazole (antiprotozoal as well as an antibacterial) were used in the formulation along with Lactobacillus acidophilus spores to treat mixed vaginal infections. From the ex vivo retention study it was found that the bioadhesive polymers hold the tablet for more than 24 hours inside the vaginal tube. The hardness of the acid-buffering bioadhesive vaginal tablet was optimized, at 4 to 5 kg hardness the swelling was found to be good and the cumulative release profile of the developed tablet was matched with a marketed conventional tablet (Infa-V). The in vitro spreadability of the swelled tablet was comparable to the marketed gel. In the in vitro antimicrobial study it was found that the acid-buffering bioadhesive tablet produces better antimicrobial action than marketed intravaginal drug delivery systems (Infa-V, Candid-V and Canesten 1).  相似文献   
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Endophytic fungi belonging to the genus Gliocladium are able to degrade plant cellulose and synthesize complex hydrocarbons under microaerophilic conditions. These fungi could thus be used to produce biofuels from cellulosics without the need for hydrolytic pretreatments. Gas chromatography-mass spectrometry-solid-phase micro-extraction (GC-MS-SPME) of head space gases from Gliocladium cultures demonstrated the production of C(6)-C(19) hydrocarbons including hexane, benzene, heptane, 3,4-dimethyl hexane, 1-octene, m-xylene, 3-methyl nonane, dodecane, tridecane, hexadecane and nonadecane directly from the cellulosic biomass. Hydrocarbon production was 100-fold higher in co-cultures of Gliocladium and Escherichia coli than in pure Gliocladium cultures. The dry mycelia weight is stable at stationary period in co-culture condition which may lead to synthesize more hydrocarbons. These fungi could potentially be developed into cost-effective biocatalysts for production of biofuels.  相似文献   
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