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961.
Honnavalli N. Kumara R. Sasi R. Suganthasakthivel Mewa Singh H. S. Sushma K. K. Ramachandran Werner Kaumanns 《International journal of primatology》2014,35(5):976-989
The status of the endemic and endangered lion-tailed macaque (Macaca silenus) has not been properly assessed in several regions of the Western Ghats of southern India. We conducted a study in Parambikulam Forest Reserve in the state of Kerala to determine the distribution, demography, and status of lion-tailed macaques. We laid 5km2 grid cells on the map of the study area (644km2) and made four replicated walks in each grid cell using GPS. We gathered data on lion-tailed macaque group locations, demography, and site covariates including trail length, duration of walk, proportion of evergreen forest, height of tallest trees, and human disturbance index. We also performed occupancy modeling using PRESENCE ver. 3.0. We estimated a minimum of 17 groups of macaques in these hills. Low detection and occupancy probabilities indicated a low density of lion-tailed macaques in the study area. Height of the tallest trees correlated positively whereas human disturbance and proportion of evergreen forest correlated negatively with occupancy in grid cells. We also used data from earlier studies carried out in the surrounding Anamalai Tiger Reserve and Nelliyampathy Hills to discuss the conservation status in the large Anamalai Hills Landscape. This landscape harbors an estimated population of 1108 individuals of lion-tailed macaques, which is about one third of the entire estimated wild population of this species. A conservation plan for this landscape could be used as a model for conservation in other regions of the Western Ghats. 相似文献
962.
Subramani Srinivasan Gajendren Sathish Mahadevan Jayanthi Jayachandran Muthukumaran Udaiyar Muruganathan Vinayagam Ramachandran 《Molecular and cellular biochemistry》2014,385(1-2):159-168
Epidemiological studies have demonstrated that diabetes mellitus is a serious health burden for both governments and healthcare providers. This study was hypothesized to evaluate the antihyperglycemic potential of eugenol by determine the activities of key enzymes of glucose metabolism in streptozotocin (STZ)-induced diabetic rats. Diabetes was induced into male albino Wistar rats by intraperitoneal administration of STZ (40 mg/kg body weight (b.w.)). Eugenol was administered to diabetic rats intragastrically at 2.5, 5, and 10 mg/kg b.w. for 30 days. The dose 10 mg/kg b.w. significantly reduced the levels of blood glucose and glycosylated hemoglobin (HbA1c) and increased plasma insulin level. The altered activities of the key enzymes of carbohydrate metabolism such as hexokinase, pyruvate kinase, glucose-6-phosphate dehydrogenase, glucose-6-phosphatase, fructose-1,6-bisphosphatase, and liver marker enzymes (AST, ALT, and ALP), creatine kinase and blood urea nitrogen in serum and blood of diabetic rats were significantly reverted to near normal levels by the administration of eugenol. Further, eugenol administration to diabetic rats improved body weight and hepatic glycogen content demonstrated the antihyperglycemic potential of eugenol in diabetic rats. The present findings suggest that eugenol can potentially ameliorate key enzymes of glucose metabolism in experimental diabetes, and it is sensible to broaden the scale of use of eugenol in a trial to alleviate the adverse effects of diabetes. 相似文献
963.
Jaclyn Ellis Ethan M. Lange Jin Li Josee Dupuis Jens Baumert Jeremy D. Walston Brendan J. Keating Peter Durda Ervin R. Fox Cameron D. Palmer Yan A. Meng Taylor Young Deborah N. Farlow Renate B. Schnabel Carola S. Marzi Emma Larkin Lisa W. Martin Joshua C. Bis Paul Auer Vasan S. Ramachandran Stacey B. Gabriel Monte S. Willis James S. Pankow George J. Papanicolaou Jerome I. Rotter Christie M. Ballantyne Myron D. Gross Guillaume Lettre James G. Wilson Ulrike Peters Wolfgang Koenig Russell P. Tracy Susan Redline Alex P. Reiner Emelia J. Benjamin Leslie A. Lange 《Human genetics》2014,133(8):985-995
C-reactive protein (CRP) is a heritable biomarker of systemic inflammation and a predictor of cardiovascular disease (CVD). Large-scale genetic association studies for CRP have largely focused on individuals of European descent. We sought to uncover novel genetic variants for CRP in a multiethnic sample using the ITMAT Broad-CARe (IBC) array, a custom 50,000 SNP gene-centric array having dense coverage of over 2,000 candidate CVD genes. We performed analyses on 7,570 African Americans (AA) from the Candidate gene Association Resource (CARe) study and race-combined meta-analyses that included 29,939 additional individuals of European descent from CARe, the Women’s Health Initiative (WHI) and KORA studies. We observed array-wide significance (p < 2.2 × 10?6) for four loci in AA, three of which have been reported previously in individuals of European descent (IL6R, p = 2.0 × 10?6; CRP, p = 4.2 × 10?71; APOE, p = 1.6 × 10?6). The fourth significant locus, CD36 (p = 1.6 × 10?6), was observed at a functional variant (rs3211938) that is extremely rare in individuals of European descent. We replicated the CD36 finding (p = 1.8 × 10?5) in an independent sample of 8,041 AA women from WHI; a meta-analysis combining the CARe and WHI AA results at rs3211938 reached genome-wide significance (p = 1.5 × 10?10). In the race-combined meta-analyses, 13 loci reached significance, including ten (CRP, TOMM40/APOE/APOC1, HNF1A, LEPR, GCKR, IL6R, IL1RN, NLRP3, HNF4A and BAZ1B/BCL7B) previously associated with CRP, and one (ARNTL) previously reported to be nominally associated with CRP. Two novel loci were also detected (RPS6KB1, p = 2.0 × 10?6; CD36, p = 1.4 × 10?6). These results highlight both shared and unique genetic risk factors for CRP in AA compared to populations of European descent. 相似文献
964.
Ramachandran Madhavan Sathish Adithya Bupesh Giridharan Moonandi Murugesan Raja Lakshman Raja 《Bioinformation》2021,17(1):46
Peptic ulcer is described in the siddha system of medicinal classification of 4448 diseases. Information on the use of Sangu Parpam in treating peptic ulcer is known. Therefore, it is of interest to document the acute and sub acute toxicity analysis on Sangu parpam in this regard. 相似文献
965.
966.
Riedel K Herbst C Leppert J Ohlenschläger O Görlach M Ramachandran R 《Journal of biomolecular NMR》2006,35(4):275-283
A simple approach is demonstrated for designing optimised broadband inversion pulses for MAS solid state NMR studies of biological systems. The method involves a two step numerical optimisation procedure and takes into account experimental requirements such as the pulse length, resonance offset range and extent of H1 inhomogeneity compensation needed. A simulated annealing protocol is used initially to find appropriate values for the parameters that define the well known tanh/tan adiabatic pulse such that a satisfactory spin inversion is achieved with minimum RF field strength. This information is then used in the subsequent stage of refinement where the RF pulse characteristics are further tailored via a local optimisation procedure without imposing any restrictions on the amplitude and frequency modulation profiles. We demonstrate that this approach constitutes a generally applicable tool for obtaining pulses with good inversion characteristics. At moderate MAS frequencies the efficacy of the method is experimentally demonstrated for generating double-quantum NMR spectra via the zero-quantum dipolar recoupling scheme RFDR. 相似文献
967.
Sørensen AL Reis CA Tarp MA Mandel U Ramachandran K Sankaranarayanan V Schwientek T Graham R Taylor-Papadimitriou J Hollingsworth MA Burchell J Clausen H 《Glycobiology》2006,16(2):96-107
The MUC1 mucin represents a prime target antigen for cancer immunotherapy because it is abundantly expressed and aberrantly glycosylated in carcinomas. Attempts to generate strong humoral immunity to MUC1 by immunization with peptides have generally failed partly because of tolerance. In this study, we have developed chemoenzymatic synthesis of extended MUC1 TR glycopeptides with cancer-associated O-glycosylation using a panel of recombinant human glycosyltransferases. MUC1 glycopeptides with different densities of Tn and STn glycoforms conjugated to KLH were used as immunogens to evaluate an optimal vaccine design. Glycopeptides with complete O-glycan occupancy (five sites per repeat) elicited the strongest antibody response reacting with MUC1 expressed in breast cancer cell lines in both Balb/c and MUC1.Tg mice. The elicited humoral immune response showed remarkable specificity for cancer cells suggesting that the glycopeptide design holds promise as a cancer vaccine. The elicited immune responses were directed to combined glycopeptide epitopes, and both peptide sequence and carbohydrate structures were important for the antigen. A MAb (5E5) with similar specificity as the elicited immune response was generated and shown to have the same remarkable cancer specificity. This antibody may hold promise in diagnostic and immunopreventive measures. 相似文献
968.
Zheng Cai Hongtao Zhang Jing Liu Alan Berezov Ramachandran Murali Qiang Wang Mark I. Greene 《Seminars in cell & developmental biology》2010,21(9):961-966
Our work is concerned with the origins and therapy of human cancers. Members of the epidermal growth factor receptor (EGFR) family of tyrosine kinases, also known as erbB or HER receptors, are over expressed and/or activated in many types of human tumors and represent important therapeutic targets in cancer therapy. Studies from our laboratory identified targeted therapy as a way to treat cancer. Rational therapeutics targeting and disabling erbB receptors have been developed to reverse the malignant properties of tumors. Reversal of the malignant phenotype, best seen with disabling the HER2 receptors using monoclonal antibodies is a distinct process from that seen with blocking of ligand binding to cognate receptors as has been done for EGFr receptors. Here we review the mechanisms of action deduced from a number of approaches developed in our laboratory and elsewhere, including monoclonal antibodies, peptide mimetics, recombinant proteins and small molecules. The biochemical and biological principles which have been uncovered during these studies of disabling HER2 homomeric or HER2-EGFr heteromeric receptors will help the development of novel and more efficient therapeutics targeting erbB family receptors. 相似文献
969.
<Emphasis Type="Italic">Acinetobacter brisouii</Emphasis> sp. nov., isolated from a wetland in Korea
Rangasamy Anandham Hang-Yeon Weon Soo-Jin Kim Yi-Seul Kim Byung-Yong Kim Soon-Wo Kwon 《Journal of microbiology (Seoul, Korea)》2010,48(1):36-39
A bacterial strain 5YN5-8T was isolated from peat layer on Yongneup in Korea. Cells of strain 5YN5-8T were strictly aerobic, Gram-negative, coccobacilli, non-spore forming, and non-motile. The isolate exhibited optimal growth
at 28°C, pH 7.0, and 0–1% NaCl. Results of 16S rRNA gene sequence analyses indicated a close relationship of this isolate
to Acinetobacter calcoaceticus (97.8% similarity for strain DSM 30006T). It also exhibited 94.4–97.8% 16S rRNA gene sequence similarities to the validly published Acinetobacter species. The value for DNA-DNA hybridization between strain 5YN5-8T and other members of the genus Acinetobacter ranged from 16 to 28%. Predominant cellular fatty acids were C18:1
ω9c, summed feature 4 containing C15:0 iso 2-OH and/or C16:1
ω7c, and C16:0. The DNA G+C content was 43.9 mol%. Phylogenetic, phenotypic, and chemotaxonomic data accumulated in this study revealed
that the isolate could be classified in a novel species of the genus Acinetobacter. The name Acinetobacter brisouii sp. nov. is proposed for the novel species, with 5YN5-8T (=KACC 11602T = DSM 18516T) as the type strain. 相似文献
970.
Sever S Skoch J Newmyer S Ramachandran R Ko D McKee M Bouley R Ausiello D Hyman BT Bacskai BJ 《The EMBO journal》2006,25(18):4163-4174
During clathrin-mediated endocytosis, the GTPase dynamin promotes formation of clathrin-coated vesicles, but its mode of action is unresolved. We provide evidence that a switch in three functional states of dynamin (dimers, tetramers, rings/spirals) coordinates its GTPase cycle. Dimers exhibit negative cooperativity whereas tetramers exhibit positive cooperativity with respect to GTP. Our study identifies tetramers as the kinetically most stable GTP-bound conformation of dynamin, which is required to promote further assembly into higher order structures such as rings or spirals. In addition, using fluorescence lifetime imaging microscopy, we show that interactions between dynamin and auxilin in cells are GTP-, endocytosis- and tetramer-dependent. Furthermore, we show that the cochaperone activity of auxilin is required for constriction of clathrin-coated pits, the same early step in endocytosis known to be regulated by the lifetime of dynamin:GTP. Together, our findings support the model that the GTP-bound conformation of dynamin tetramers stimulates formation of constricted coated pits at the plasma membrane by regulating the chaperone activity of hsc70/auxilin. 相似文献