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101.
102.
Knowledge on the occurrence and distribution of species is crucial for designing and evaluating conservation strategies within a geographical region. Similipal Tiger Reserve though confined to a small area needs information on the diversity and abundance of mammalian fauna to ensure conservation of tiger. Thus, we aimed to assess the diversity and abundance of medium to large sized mammals in Similipal Tiger Reserve by using remotely triggered camera traps. A total of 6413 camera trap days at 187 trap stations were deployed from November 2012 to July 2013 to estimate the status of mammal. We obtained 3763 independent photographs and detected 24 species of mammals. The relative abundance index of each mammalian species was calculated. Leopard (Panthera pardus) was the most abundant carnivore while barking deer (Muntiacus muntjac) was the most abundant prey. Anthropogenic activities like hunting, livestock grazing and free ranging domestic dogs were found to be the detrimental factors for the existing mammalian species. These activities should be addressed through conservation and development perception with an interdisciplinary approach, incorporating social and ecological components cautiously.  相似文献   
103.
The relationship between fatty acid binding proteins, ATP citrate lyase activity and fatty acid synthesis in developing human placenta has been studied. Fatty acid binding proteins reverse the inhibitory efect of palmitoyl-CoA and oleate on ATP citrate lyase and fatty acid synthesis. In the absence of these inhibitors fatty acid binding proteins activate ATP citrate lyase and stimulate [ 1-14 C] acetate incorporation into placental fatty acids indicating binding of endogenous inhibitors by these proteins. Thus these proteins regulate the supply of acetyl-CoA as well as the synthesis of fatty acids from that substrates. As gestation proceeds and more lipids are required by the developing placenta fatty acid binding protein content, activity of ATP citrate lyase and rate of fatty acid synthesis increase indicating a cause and efect relationship between the demand of lipids and supply of precursor fatty acids during human placental development.  相似文献   
104.

Background  

Bioinformatics often leverages on recent advancements in computer science to support biologists in their scientific discovery process. Such efforts include the development of easy-to-use web interfaces to biomedical databases. Recent advancements in interactive web technologies require us to rethink the standard submit-and-wait paradigm, and craft bioinformatics web applications that share analytical and interactive power with their desktop relatives, while retaining simplicity and availability.  相似文献   
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106.
Co-delivery of chemotherapeutic agents using nanocarriers is a promising strategy for enhancing therapeutic efficacy of anticancer agents. The aim of this work was to develop tamoxifen and imatinib dual drug loaded temperature-sensitive liposomes to treat breast cancer. Liposomes were prepared using 1, 2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), monopalmitoyl-2-hydroxy-sn-glycero-3-phosphocholine (MPPC), and different surface active agents. The liposomes were characterized for the average particle size, zeta potential, transition temperature, and drug release below and above liposomal transition temperature. The temperature-sensitive liposomes co-encapsulated with tamoxifen and imatinib were investigated for their synergistic activity against MCF-7 and MDA-MB-231 breast cancer cells. The liposomal nanoparticles showed a transition temperature of 39.4?°C and >70% encapsulation efficiency for tamoxifen and imatinib. The temperature-responsive liposomes showed more than 80% drug released within 30?min above transition temperature. Dual drug loaded liposomes showed synergistic growth inhibition against MCF-7 and MDA-MB-231 breast cancer cells. Co-delivery of tamoxifen and imatinib using temperature-sensitive liposomes can be developed as a potential targeting strategy against breast cancer.  相似文献   
107.
We have recently shown that the conditioned media from bovine oviductal epithelial cell culture suppress sperm phagocytosis by neutrophils, suggesting that the oviduct around oestrus supplies the anti‐inflammatory microenvironment. To investigate the immune response of neutrophils toward the sperm at ovulation in the buffalo oviduct, we examined (a) a detailed distribution of neutrophils in the oviduct in buffaloes, (b) the effect of ovulatory follicular fluid (FF) and oviductal fluid (OF) on sperm phagocytosis by neutrophils, and (c) the interaction of the ovulatory FF with OF on sperm phagocytosis by neutrophils in vitro. Buffalo oviducts were collected from healthy reproductive tracts at a local slaughterhouse. A detailed observation by histological examination and transmission electron microscopy revealed that neutrophils exist in the oviduct epithelium and lumen throughout the oestrous cycle in buffaloes. The number of neutrophils at the oestrus stage was higher in ampulla compared with those in isthmus, whereas they remained relatively constant at the dioestrus stage. Two hours of preincubation of neutrophils with FF enhanced sperm phagocytosis through the formation of neutrophil extracellular traps (NETs) together with H2O2 production, whereas OF around oestrus (eOF) suppressed sperm phagocytosis, NETs formation, and H2O2 production and relieved the above FF‐induced inflammatory response. Our findings show that neutrophils exist in the healthy cyclic oviduct across bovine species, and the OF supplies a strong anti‐inflammatory environment that could minimize the inflammatory effect of the FF that flows into the oviduct lumen after ovulation and supports the occurrence of fertilization.  相似文献   
108.
Trancriptomic analysis of the venom gland cDNA library of Bungarus flaviceps revealed Kunitz‐type serine protease inhibitor as one of the major venom protein families with three groups A, B, C. One of the group B isoforms named Flavikunin, which lacked an extra cysteine residue involved in disulfide bond formation in β‐bungarotoxin, was synthesized, cloned, and overexpressed in Escherichia coli. To decipher the structure‐function relationship, the P1 residue of Flavikunin, histidine, was mutated to alanine and arginine. Purified wild‐type and mutant Flavikunins were screened against serine proteases‐thrombin, factor Xa, trypsin, chymotrypsin, plasmin, and elastase. The wild‐type and mutant Flavikunin (H?R) inhibited plasmin with an IC 50 of 0.48 and 0.35 µM, respectively. The in‐silico study showed that P1 residue of wild‐type and mutant (H?R) Flavikunin interacted with S1′ and S1 site of plasmin, respectively. Thus, histidine at the P1 position was found to be involved in plasmin inhibition with mild anticoagulant activity.  相似文献   
109.
The ability of Plasmodium falciparum-infected red blood cells (IRBCs) to bind to vascular endothelium, thus enabling sequestration in vital host organs, is an important pathogenic mechanism in malaria. Adhesion of P. falciparum IRBCs to platelets, which results in the formation of IRBC clumps, is another cytoadherence phenomenon that is associated with severe disease. Here, we have used in vitro cytoadherence assays to demonstrate, to our knowledge for the first time, that P. falciparum IRBCs use the 32-kDa human protein gC1qR/HABP1/p32 as a receptor to bind to human brain microvascular endothelial cells. In addition, we show that P. falciparum IRBCs can also bind to gC1qR/HABP1/p32 on platelets to form clumps. Our study has thus identified a novel host receptor that is used for both adhesion to vascular endothelium and platelet-mediated clumping. Given the association of adhesion to vascular endothelium and platelet-mediated clumping with severe disease, adhesion to gC1qR/HABP1/p32 by P. falciparum IRBCs may play an important role in malaria pathogenesis.  相似文献   
110.
The thiopurine antimetabolite 6-mercaptopurine (6MP) is an important chemotherapeutic drug in the conventional treatment of childhood acute lymphoblastic leukemia (ALL). 6MP is mainly catabolized by both hypoxanthine-guanine phosphoribosyltransferase (HGPRT) and xanthine oxidase (XOD) to form thioinosinic monophosphate (TIMP) (therapeutically active metabolite) and 6-thiouric acid (6TUA) (inactive metabolite), respectively. The activity of both the enzymes varies among ALL patients governing the active and the inactive metabolite profile within the immature lymphocytes. Therefore, an attempt was made to study the kinetic nature of the branched bi-enzyme system acting on 6MP and to quantitate TIMP and 6TUA formed when the two enzymes are present in equal and variable ratios. The quantification of the branched kinetics using spectrophotometric method presents problem due to the closely apposed lambda(max) of the substrates and products. Hence, employing an HPLC method, the quantification of the products was done with the progress of time. The limit of quantification (LOQ) of substrate was found to be 10nM and for products as 50 nM. The limit of detection (LOD) was found to be 1 nM for the substrate and the products. The method exhibited linearity in the range of 0.01-100 microM for 6MP and 0.05-100 microM for both 6TUA and TIMP. The amount of TIMP formed was higher than that of 6TUA in the bi-enzyme system when both the enzymes were present in equivalent enzymatic ratio. It was further found that enzymatic ratios play an important role in determining the amounts of TIMP and 6TUA. This method was further validated using actively growing T-ALL cell line (Jurkat) to study the branched kinetics, wherein it was observed that treatment of 50 microM 6MP led to the generation of 12 microM TIMP and 0.8 microM 6TUA in 6 h at 37 degrees C.  相似文献   
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