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101.
102.
Alsaba F Raja Furqan Ali Inshad A Khan Abdul S Shawl Daljit S Arora Bhahwal A Shah Subhash C Taneja 《BMC microbiology》2011,11(1):54
Background
Boswellic acids are pentacyclic triterpenes, which are produced in plants belonging to the genus Boswellia. Boswellic acids appear in the resin exudates of the plant and it makes up 25-35% of the resin. β-boswellic acid, 11-keto-β-boswellic acid and acetyl-11-keto-β-boswellic acid have been implicated in apoptosis of cancer cells, particularly that of brain tumors and cells affected by leukemia or colon cancer. These molecules are also associated with potent antimicrobial activities. The present study describes the antimicrobial activities of boswellic acid molecules against 112 pathogenic bacterial isolates including ATCC strains. Acetyl-11-keto-β-boswellic acid (AKBA), which exhibited the most potent antibacterial activity, was further evaluated in time kill studies, postantibiotic effect (PAE) and biofilm susceptibility assay. The mechanism of action of AKBA was investigated by propidium iodide uptake, leakage of 260 and 280 nm absorbing material assays. 相似文献103.
Introduction
The vast difference in the abundance of different proteins in biological samples limits the determination of the complete proteome of a cell type, requiring fractionation of proteins and peptides before MS analysis. 相似文献104.
Vijayabharathi R Bruheim P Andreassen T Raja DS Devi PB Sathyabama S Priyadarisini VB 《Journal of microbiology (Seoul, Korea)》2011,49(6):920-926
A new actinomycete strain, isolated from humus soils in the Western Ghats, was found to be an efficient pigment producer.
The strain, designated AAA5, was identified as a putative Streptomyces aurantiacus strain based on cultural properties, morphology, carbon source utilization, and analysis of the 16S rRNA gene. The strain
produced a reddish-brown pigmented compound during the secondary metabolites phase. A yellow compound was derived from the
extracted pigment and was identified as the quinone-related antibiotic resistomycin based on ultraviolet-visible spectrophotometry,
fourier transform infrared spectroscopy, liquid chromatography and mass spectroscopy, and nuclear magnetic resonance analyses.
The AAA5 strain was found to produce large quantities of resistomycin (52.5 mg/L). It showed potent cytotoxic activity against
cell lines viz. HepG2 (hepatic carcinoma) and HeLa (cervical carcinoma) in vitro, with growth inhibition (GI50) of 0.006 and 0.005 μg/ml, respectively. The strain also exhibited broad antimicrobial activities against both Gram-positive
and Gram-negative bacteria. Therefore, AAA5 may have great potential as an industrial resistomycin-producing strain. 相似文献
105.
Kumar S Prahalathan P Raja B 《Redox report : communications in free radical research》2011,16(5):208-215
We investigated the antihypertensive and antioxidant potential of vanillic acid (VA) in N(ω)-Nitro-L-arginine methyl ester hydrochloride (L-NAME) - treated adult male albino Wistar rats. Treatment of rats with L-NAME (40 mg/kg Bw for 30 days) caused a sustained increase in systolic- (SBP) and diastolic blood pressure (DBP) and significantly decreased the concentration of nitrite/nitrate (NO(x)) in plasma as compared with that in the control. Rats treated with VA restored SBP and DBP to normal level and preserve the plasma NO metabolites concentration. Moreover, VA reduced lipid peroxidation products (thiobarbituric acid reactive substances, lipid hydroperoxides, conjugated dienes) and significantly restored enzymatic antioxidants (superoxide dismutase, catalase, and glutathione peroxidase), non-enzymatic antioxidants (vitamin C, vitamin E, and reduced glutathione) in the plasma. To assess the toxicity if any of VA treatment, hepatic and renal function markers were measured. Our results showed that the effect at a dose of 50 mg/kg Bw of VA was more pronounced than that of the other two doses, 25 and 100 mg/kg Bw. These results were supported by histopathology studies. We conclude that VA possesses an antihypertensive and antioxidant activity in L-NAME-induced hypertensive rats. 相似文献
106.
Sylvie Cloutier Raja Ragupathy Zhixia Niu Scott Duguid 《Molecular breeding : new strategies in plant improvement》2011,28(4):437-451
Flax (Linum usitatissimum L.) seeds contain nearly 50% oil which is high in linolenic acid (an omega-3 fatty acid). In this study, a genetic linkage
map was constructed based on 114 expressed sequence tag-derived simple sequence repeat (SSR) markers in addition to five single
nucleotide polymorphism markers, five genes (fad2A, fad2B, fad3A, fad3B and dgat1) and one phenotypic trait (seed coat color), using a doubled haploid (DH) population of 78 individuals generated from a cross
between SP2047 (a yellow-seeded Solin™ line with 2–4% linolenic acid) and UGG5-5 (a brown-seeded flax line with 63–66% linolenic
acid). This map consists of 24 linkage groups with 113 markers spanning ~833.8 cM. Quantitative trait locus (QTL) analysis
detected two major QTLs each for linoleic acid (LIO, QLio.crc-LG7, QLio.crc-LG16), linolenic acid (LIN, QLin.crc-LG7, QLin.crc-LG16) and iodine value (IOD, QIod.crc-LG7, QIod.crc-LG16), and one major QTL for palmitic acid (PAL, QPal.crc-LG9). The mutant allele of fad3A, mapped to the chromosomal segment inherited from the parent SP2047, underlies the QTL on linkage group 7 and was positively
associated with high LIO content but negatively associated with LIN and IOD. This fad3A locus accounted for approximately 34, 25 and 29% of the phenotypic variation observed in this DH population for these three
traits, respectively. The QTL localized on linkage group 16 explained approximately 20, 25 and 13% of the phenotypic variation
for these same traits, respectively. For palmitic acid, QPal.crc-LG9 accounted for ~42% of the phenotypic variation. This first SSR-based linkage map in flax will serve as a resource for mapping
additional markers, genes and traits, in map-based cloning and in marker-assisted selection. 相似文献
107.
Objectives
To study the diagnostic delay for pituitary stalk interruption syndrome (PSIS) with growth hormone deficiency (GHD) and the sensitivity of the auxological criteria of the Growth Hormone Research Society (GHRS) consensus guidelines.Methods
A single-center retrospective case-cohort study covering records from January 2000 through December 2007 evaluated the performance of each GHRS auxological criterion for patients with GHD and PSIS. Diagnostic delay was calculated as the difference between the age at which the earliest GHRS criterion could have been observed and the age at diagnosis of PSIS with GHD. A diagnostic delay exceeding one year was defined as late diagnosis.Results
The study included 21 patients, 16 (76%) of whom had isolated GHD and 5 (24%) multiple pituitary hormone deficiencies. The median age at diagnosis was 3.6 years (interquartile range, IQR, 2.6–5.5). The median diagnostic delay was 2.3 years (range 0–12.6; IQR 1.5–3.6), with late diagnosis for 17 patients (81%). Height more than 1.5 SDS below target height was the most effective criterion: 90% of the patients met the criterion before diagnosis at a median age of 1 year, and it was the first criterion to be fulfilled for 84%.Conclusion
In our cohort, the delay for diagnosis of PSIS with GHD was long and could have been reduced by using the GHRS criteria, in particular, height more than 1.5 SDS below the target height. The specificity of such a strategy needs to be tested in healthy populations. 相似文献108.
109.
Background
The entire gastrointestinal tract is protected by a mucous layer, which contains complex glycoproteins called mucins. MUC2 is one such mucin that protects the colonic mucosa from invading microbes. The initial interaction between microbes and mucins is an important step for microbial pathogenesis. Hence, it was of interest to investigate the relationship between host (mucin) and pathogen interaction, including Shigella induced expression of MUC2 and IL-1β during shigellosis.Methods
The mucin-Shigella interaction was revealed by an in vitro mucin-binding assay. Invasion of Shigella dysenteriae into HT-29 cells was analyzed by Transmission electron microscopy. Shigella induced mucin and IL-1β expression were analyzed by RT-PCR and Immunofluorescence.Results
The clinical isolates of Shigella were found to be virulent by a congo-red binding assay. The in vitro mucin-binding assay revealed both Shigella dysenteriae and Shigella flexneri have binding affinity in the increasing order of: guinea pig small intestinal mucinConclusions
Our study concludes that the Shigella species specifically binds to guinea pig colonic mucin, but not to guinea pig small intestinal mucin. The guinea pig colonic mucin showed a greater binding parameter (R), and more saturable binding, suggesting the presence of a finite number of receptor binding sites in the colonic mucin of the host. In addition, modification of mucins with TFMS and sodium metaperiodate significantly reduced mucin-bacterial binding; suggesting that the mucin-Shigella interaction occurs through carbohydrate epitopes on the mucin backbones. Overproduction of MUC2 may alter adherence and invasion of Shigella dysenteriae into human colonic epithelial cells. 相似文献110.
Sanders LH Devadoss B Raja GV O'Connor J Su S Wozniak DJ Hassett DJ Berdis AJ Sutton MD 《PloS one》2011,6(4):e18824
Pseudomonas aeruginosa is especially adept at colonizing the airways of individuals afflicted with the autosomal recessive disease cystic fibrosis (CF). CF patients suffer from chronic airway inflammation, which contributes to lung deterioration. Once established in the airways, P. aeruginosa continuously adapts to the changing environment, in part through acquisition of beneficial mutations via a process termed pathoadaptation. MutS and DinB are proposed to play opposing roles in P. aeruginosa pathoadaptation: MutS acts in replication-coupled mismatch repair, which acts to limit spontaneous mutations; in contrast, DinB (DNA polymerase IV) catalyzes error-prone bypass of DNA lesions, contributing to mutations. As part of an ongoing effort to understand mechanisms underlying P. aeruginosa pathoadaptation, we characterized hydrogen peroxide (H(2)O(2))-induced phenotypes of isogenic P. aeruginosa strains bearing different combinations of mutS and dinB alleles. Our results demonstrate an unexpected epistatic relationship between mutS and dinB with respect to H(2)O(2)-induced cell killing involving error-prone repair and/or tolerance of oxidized DNA lesions. In striking contrast to these error-prone roles, both MutS and DinB played largely accurate roles in coping with DNA lesions induced by ultraviolet light, mitomycin C, or 4-nitroquinilone 1-oxide. Models discussing roles for MutS and DinB functionality in DNA damage-induced mutagenesis, particularly during CF airway colonization and subsequent P. aeruginosa pathoadaptation are discussed. 相似文献