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1.
Two polypeptides of 74 kDa and 55 kDa have been isolated from human platelets by immunoaffinity and lectin affinity chromatography and their effects on thrombin reactivity have been examined. These proteins in combination enhanced the aggregation of platelets by thrombin while aggregation induced by trypsin, collagen and adenosine diphosphate was not significantly affected. An enhancement in the action of thrombin on fibrinogen, N-benzoylarginine ethyl ester and H-D-phenylalanyl-L-pipecolyl-L-arginine-p-nitroanilide dihydrochloride was also observed in the presence of the platelet proteins. Under similar conditions, the proteins did not influence the esterolytic activity of trypsin or plasmin. Studies at different thrombin and protein concentrations showed maximum enhancement of enzyme reactivity when the ratio between the peptides and thrombin was optimal. In the presence of these proteins, the affinity of thrombin for N-benzoylarginine ethyl ester was about twofold higher than in the control. Two polypeptides with properties similar to those described above have also been isolated from human plasma. Antibodies to the above proteins isolated from either platelets or plasma were raised in rabbits. Intact platelets solubilized in Triton X-100 or plasma showed two precipitin lines in immunoelectrophoresis against both of the above antisera and a similar pattern was observed with the isolated polypeptides. The polypeptides did not interact in immunoelectrophoresis with antisera to whole serum, antithrombin, C4 binding protein or protein S. These 74-kDa and 55-kDa polypeptides contained radioactivity when radioiodinated platelets were used suggesting that they are located on the cell surface. Fresh plasma was analyzed by gel electrophoresis under nondenaturing and denaturing conditions and the proteins were transferred to nitrocellulose sheets. Staining with antibody to these thrombin-reactive proteins and 125I-protein A showed several reactive plasma proteins under nondenaturing conditions with the major band migrating in the albumin area. In plasma treated with sodium dodecyl sulfate, the 74-kDa and 55-kDa components were observed. A prominent 74-kDa band and a fainter 55-kDa component were again observed when platelets solubilized in sodium dodecyl sulfate were analysed by the above procedure. It is proposed that human platelets and plasma contain polypeptides which may directly modulate thrombin reactivity.  相似文献   
2.
Clinical decision is often difficult with chlorhexidine mouthwash. The use of antioxidant mouthwashes for the treatment of periodontal disease is in practise. Therefore, it is of interest to collect gleaned information on Antioxidant mouthwashes as periodontal therapy from known literature. Improvement in treatment using antioxidant mouthwashes is reported in several studies. The mouthwash with antioxidants has similar anti-gingivitis, antiplaque and antimicrobial effects as that of chlorhexidine mouthwash.  相似文献   
3.
Abstract

Molecular diagnosis, chemo-diagnosis and physiological parameter have been applied for detecting the Ganoderma disease of coconut. Polyclonal antibodies (PAbs) raised against mycelial protein of Ganoderma, specific mycelial protein (62 kDa) of Ganoderma isolates and basidiocarp protein of Ganoderma were used for detection. All the PAbs could detect Ganoderma in diseased coconut root tissues in early stage of the disease before symptom expression by indirect – ELISA at the antiserum dilution of 1:1000 for mycelial protein, 1:700 for specific protein and 1:3000 for basidiocarp protein. Low cross reactions were observed with saprophytic fungi occurring in coconut roots and also with other basidiomycetous fungi. For polymerase chain reaction tests, the primer was generated from the internal transcribed spacer region one (ITS 1) of rDNA of Ganoderma, which produced a PCR product of 167 bp in size. Utility of this method was confirmed at the field level.  相似文献   
4.
Abstract

Three antagonists: Pseudomonas fluorescens (Pf1), Bacillus subtilis and Trichoderma viride, were tested alone and in combination for suppression of onion leaf blight (Alternaria palandui) disease under glasshouse and field conditions. The average mean of disease reduction was 24.81% for single strains and 42.44% for mixtures. In addition to disease suppression, treatment with a mixture of antagonists promoted plant growth in terms of increased plant height and ultimately bulb yield. Though seed treatment of either single strain or strain mixtures alone could reduce the disease, subsequent application to root, leaves or soil further reduced the disease and enhanced the plant growth. The mixture consisting of Pseudomonas fluorescens Pf1 plus Bacillus subtilis plus Trichoderma viride was the most effective in reducing the disease and in promoting plant growth and bulb yield in greenhouse and field tests.  相似文献   
5.
Vitamin B12 is an essential micronutrient synthesized by microorganisms. Mammals including humans have evolved ways for transport and absorption of this vitamin. Deficiency of vitamin B12 (either due to low intake or polymorphism in genes involved in absorption and intracellular transport of this vitamin) has been associated with various complex diseases. Genome-wide association studies have recently identified several common single nucleotide polymorphisms (SNPs) in fucosyl transferase 2 gene (FUT2) to be associated with levels of vitamin B12—the strongest association was with a non-synonymous SNP rs602662 in this gene. In the present study, we attempted to replicate the association of this SNP (rs602662) in an Indian population since a significant proportion has been reported to have low levels of vitamin B12 in this population. A total of 1146 individuals were genotyped for this SNP using a single base extension method and association with levels of vitamin B12 was assessed in these individuals. Regression analysis was performed to analyze the association considering various confounding factors like for age, sex, diet, hypertension, diabetes mellitus and coronary artery disease status. We found that the SNP rs602662 was significantly associated with the levels of vitamin B12 (p value < 0.0001). We also found that individuals adhering to a vegetarian diet with GG (homozygous major genotype) have significantly lower levels of vitamin B12 in these individuals. Thus, our study reveals that vegetarian diet along with polymorphism in the FUT2 gene may contribute significantly to the high prevalence of vitamin B12 deficiency in India.  相似文献   
6.
The experimental and theoretical studies on the molecular structure and vibrational spectra of bis(thiourea)zinc(II) chloride (BTZC) crystals were investigated. The Fourier transform infrared, Fourier transform Raman and UV–vis spectra of BTZC were recorded. The molecular geometry and vibrational frequencies of BTZC in the ground state were calculated by using B3LYP with LANL2DZ as basis set. Comparison of the observed structural parameters of BTZC with single-crystal X-ray studies yields a good agreement. Vibrational analysis of the simultaneous IR and Raman activation of the Zn–Cl stretching mode in the molecule provides the evidence for the charge transfer interaction taking place within the molecule. The energy and oscillator strength are calculated by time-dependent density functional theory. The simulated spectra satisfactorily coincide with the experimental spectra.  相似文献   
7.
Vibrational frequencies and geometrical parameters of 4-piperidone (4-PID) in the ground state have been calculated by using the Hartree–Fock (HF) and density functional methods (B3LYP) with 6-311++G(d,p) and 6-311+G(3df,2p) basis sets. These methods are proposed as a tool to be applied in the structural characterisation of 4-PID (C5H9NO). The title molecule has C s point group symmetry, thus providing useful support in the interpretation of experimental IR and Raman data. The DFT-B3LYP/6-311+G(3df,2p) calculations have been found more reliable than the ab initio HF/6-311++G(d,p) calculations for the vibrational study of 4-PID. The calculated highest occupied molecular orbital and lowest unoccupied molecular orbital energies show that charge transfer occurs within the molecule. The theoretical spectrograms for FT-IR and FT-Raman spectra of the title molecule have been constructed.  相似文献   
8.
Sorghum with its remarkable adaptability to drought and high temperature provides a model system for grass genomics and resource for gene discovery especially for abiotic stress tolerance. Group 3 LEA genes from barley and rice have been shown to play crucial role in abiotic stress tolerance. Here, we present a genome-wide analysis of LEA3 genes in sorghum. We identified four genes encoding LEA3 proteins in the sorghum genome and further classified them into LEA3A and LEA3B subgroups based on the conservation of LEA3 specific motifs. Further, expression pattern of these genes were analyzed in seeds during development and vegetative tissues under abiotic stresses. SbLEA3A group genes showed expression at early stage of seed development and increased significantly at maturity, while SbLEA3B group genes expressed only in matured seeds. Expression of SbLEA3 genes in response to abiotic stresses such as soil moisture deficit (drought), osmotic, salt, and temperature stresses, and exogenous ABA treatments was also studied in the leaves of 2-weeks-old seedlings. ABA and drought induced the expression of all LEA3 genes, while cold and heat stress induced none of them. Promoter analysis revealed the presence of multiple ABRE core cis-elements and a few low temperature response (LTRE)/drought responsive (DRE) cis-elements. This study suggests non-redundant function of LEA3 genes in seed development and stress tolerance in sorghum.  相似文献   
9.
The present research explored the dynamics of competitive advantages in intercollegiate athletics by investigating the contribution of intangible resources (i.e., athletic and academic reputations) on the generation of more tangible resources (i.e., human and financial resources), which in turn influence the athletic performance (i.e., winning record) and academic performance (i.e., graduation rates), and gender equity. The research was based entirely on archival data of 324 NCAA Division I member institutions. The results of the SEM supported the study’s basic arguments that tangible resources are the sources of competitive advantages in Division I intercollegiate athletics, and that intangible resources contribute to the generation of tangible resources.  相似文献   
10.
There are very few reports that describe the mutational landscape of cervical cancer, one of the leading cancers in Indian women. The aim of the present study was to investigate the somatic mutations that occur in cervical cancer. Whole exome sequencing of 10 treatment naïve tumour biopsies with matched blood samples, from a cohort of Indian patients with locally advanced disease, was performed. The data revealed missense mutations across 1282 genes, out of 1831 genes harbouring somatic mutations. These missense mutations (nonsynonymous + stop-gained) when compared with pre-existing mutations in the COSMIC database showed that 272 mutations in 250 genes were already reported although from cancers other than cervical cancer. More than 1000 novel somatic variations were obtained in matched tumour samples. Pathways / genes that are frequently mutated in various other cancers were found to be mutated in cervical cancers. A significant enrichment of somatic mutations in the MAPK pathway was observed, some of which could be potentially targetable. This is the first report of whole exome sequencing of well annotated cervical cancer samples from Indian women and helps identify trends in mutation profiles that are found in an Indian cohort of cervical cancer.  相似文献   
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