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961.
Diabetic nephropathy is a major "microvascular" complication of diabetes, differs from other causes of chronic kidney diseases in its predictability, with well-defined functional progression from hyperfiltration to micro- to macroalbuminuria to renal failure. The present study was undertaken to investigate the effect of Asparagus racemosus Willd (Liliaceae) on streptozotocin-induced early diabetic nephropathy. Single i.p injection of streptozotocin (55 mg/kg) was administered to induce early diabetic nephropathy in Wistar rats and thereafter treated orally with ethanolic extract of Asparagus racemosus (EEAR) at a dose level of 100 and 250 mg/kg daily for 4 weeks. The efficacy of extract was compared with diabetic control rats. A. racemosus treatment significantly decreased plasma glucose, creatinine, urea nitrogen, total cholesterol and triglyceride levels. Renal hypertrophy, polyuria, hyperfiltration, microalbuminuria and abnormal changes in the renal tissue as well as oxidative stress were effectively attenuated by EEAR treatment. Basement membrane thickening and mesangial proliferation formation without nodules were seen in diabetic rats, whereas these structural changes were reduced in EEAR treated groups. Results of this study suggested that A. racemosus has beneficial effect in the treatment of diabetic 相似文献
962.
Traditional methods of species classification and identification of the organism are based on morphological, physiological, biochemical,
developmental and nutritional characteristics. Accurate assignment of taxonomic status to the new biologically active microbial isolates through
existing bioinformatics methods is now very essential and also helpful in chemical characterization of the active molecule produced by
microorganisms. The bacterial strain M4 (ckm7) was isolated from the pre-treated soil sample collected from the agricultural field of Eastern
Uttar Pradesh (U.P.), India and was found to be producing antibacterial and antifungal antibiotics. Taxonomic identification of the isolate belongs
to the genus Streptomyces which was done with the help of sequence analysis and later confirmed by biological activity. Sequence comparison
study of ckm7 showed 98% identical similarity with 16S rRNA gene sequences of Streptomyces spinichromogenes, Streptomyces triostinicus and
Streptomyces capoamus. On the basis of both biological activity and phylogenetic analysis of ckm7, it was concluded that the isolated strain is a
new variant of S. triostinicus. 相似文献
963.
Root Suberin Forms an Extracellular Barrier That Affects Water Relations and Mineral Nutrition in Arabidopsis 总被引:3,自引:0,他引:3
Ivan Baxter Prashant S. Hosmani Ana Rus Brett Lahner Justin O. Borevitz Balasubramaniam Muthukumar Michael V. Mickelbart Lukas Schreiber Rochus B. Franke David E. Salt 《PLoS genetics》2009,5(5)
Though central to our understanding of how roots perform their vital function of scavenging water and solutes from the soil, no direct genetic evidence currently exists to support the foundational model that suberin acts to form a chemical barrier limiting the extracellular, or apoplastic, transport of water and solutes in plant roots. Using the newly characterized enhanced suberin1 (esb1) mutant, we established a connection in Arabidopsis thaliana between suberin in the root and both water movement through the plant and solute accumulation in the shoot. Esb1 mutants, characterized by increased root suberin, were found to have reduced day time transpiration rates and increased water-use efficiency during their vegetative growth period. Furthermore, these changes in suberin and water transport were associated with decreases in the accumulation of Ca, Mn, and Zn and increases in the accumulation of Na, S, K, As, Se, and Mo in the shoot. Here, we present direct genetic evidence establishing that suberin in the roots plays a critical role in controlling both water and mineral ion uptake and transport to the leaves. The changes observed in the elemental accumulation in leaves are also interpreted as evidence that a significant component of the radial root transport of Ca, Mn, and Zn occurs in the apoplast. 相似文献
964.
Nataraj Sekhar Pagadala Manish Arha P. S. Reddy Ranadheer Kumar V. L. Sirisha S. Prashant K. Janardhan Reddy Bashir Khan S. K. Rawal P. B. Kavi Kishor 《Journal of molecular modeling》2009,15(2):203-221
Caffeoyl coenzyme A O-methyltransferase (CCoAOMT) is an important enzyme that participates in lignin biosynthesis especially in the formation of
cell wall ferulic esters of plants. It plays a pivotal role in the methylation of the 3-hydroxyl group of caffeoyl CoA. Two
cDNA clones that code CCoAOMT were isolated earlier from subabul and in the present study; 3D models of CCoAOMT1 and CCoAOMT2
enzymes were built using the MODELLER7v7 software to find out the substrate binding sites. These two proteins differed only
in two amino acids and may have little or no functional redundancy. Refined models of the proteins were obtained after energy
minimization and molecular dynamics in a solvated water layer. The models were further assessed by PROCHECK, WHATCHECK, Verify_3D
and ERRAT programs and the results indicated that these models are reliable for further active site and docking analysis.
The refined models showed that the two proteins have 9 and 10 α-helices, 6 and 7 β-sheets respectively. The models were used
for docking the substrates CoA, SAM, SAH, caffeoyl CoA, feruloyl CoA, 5-hydroxy feruloyl CoA and sinapyl CoA which showed
that CoA and caffeoyl CoA are binding with high affinity with the enzymes in the presence and absence of SAM. It appears therefore
that caffeoyl CoA is the substrate for both the isoenzymes. The results also indicated that CoA and caffeoyl CoA are binding
with higher affinity to CCoAOMT2 than CCoAOMT1. Therefore, CCoAOMT2 conformation is thought to be the active form that exists
in subabul. Docking studies indicated that conserved active site residues Met58, Thr60, Val63, Glu82, Gly84, Ser90, Asp160,
Asp162, Thr169, Asn191 and Arg203 in CCoAOMT1 and CCoAOMT2 enzymes create the positive charge to balance the negatively charged
caffeoyl CoA and play an important role in maintaining a functional conformation and are directly involved in donor-substrate
binding. 相似文献
965.
Prashant R. Bharadwaj Ashok K. Dubey Colin L. Masters Ralph N. Martins Ian G. Macreadie 《Journal of cellular and molecular medicine》2009,13(3):412-421
Amyloid β protein (Aβ) has been associated with Alzheimer's disease (AD) because it is a major component of the extracellular plaque found in AD brains. Increased Aβ levels correlate with the cognitive decline observed in AD. Sporadic AD cases are thought to be chiefly associated with lack of Aβ clearance from the brain, unlike familial AD which shows increased Aβ production. Aβ aggregation leading to deposition is an essential event in AD. However, the factors involved in Aβ aggregation and accumulation in sporadic AD have not been completely characterized. This review summarizes studies that have examined the factors that affect Aβ aggregation and toxicity. By necessity these are studies that are performed with recombinant-derived or chemically synthesized Aβ. The studies therefore are not done in animals but in cell culture, which includes neuronal cells, other mammalian cells and, in some cases, non-mammalian cells that also appear susceptible to Aβ toxicity. An understanding of Aβ oligomerization may lead to better strategies to prevent AD. 相似文献
966.
Bacterial blight caused by Xanthomonas campestris pv. punicae (Xcp) has emerged as a potential threat in pomegranate (Punica granatum) cultivation in India. Here, we report the genomic fingerprints and their correlation with virulence pattern of Xcp isolates
from Maharashtra and Delhi. The genomic fingerprints of Xcp isolates were generated using enterobacterial repetitive intergenic
consensus (ERIC) sequence-based primers, and virulence level was based on their reaction upon infiltration to susceptible
pomegranate cultivar. Maharashtra isolate PGM1 showed only 50% similarity with Delhi isolate PGD8 forming a distinct genotype,
whereas the Delhi isolates PGD5 and PGD6 form a cluster with Maharashtra isolates PGM2 and PGM4. The isolates PGM2, PGM4,
PGD5, and PGD6 showing mean disease score of 7.47 were marked as group A or highly virulent. The moderately virulent or group
B isolates PGM3 and PGD7 produced mean disease score of 4.19, whereas less virulent or group C isolates PGD8 and PGM1 gave
mean disease intensity of 1.91. A correlation between genotypic groups based on ERIC fingerprints and pathogenicity of the
isolates was established. The highly virulent isolates PGM2, PGM4, PGD5, and PGD6 formed a single cluster. A unique 900 bp
amplicon present in all highly virulent isolates has been identified that can be used as genetic marker to screen isolates
for virulence. The less virulent isolates PGD8 and PGM1 formed single cluster at 50% similarity coefficient. This seems to
be the first report to establish a correlation between ERIC-PCR fingerprints and their corresponding virulence pattern of
the pomegranate bacterial blight pathogen. 相似文献
967.
Padmalaya Das Mani Chopra Avadhesh C. Sharma 《Molecular and cellular biochemistry》2009,323(1-2):61-68
This study was designed to test whether increased sympathetic stimulation during polymicrobial sepsis modulates the profile of the syntaxin1A and norepinephrine transporter (NET) in the heart. Sepsis of mild and severe intensity was induced in male Sprague-Dawley rats (275–350 g) using the cecal inoculum (CI) and cecal ligation and puncture (CLP) methods, respectively. The heart samples were isolated from sham, 1, 3, and 7 day post-sepsis in the CI model and at 2 and 20 h post-sepsis in the CLP model. In the CI model, the plasma concentration of norepinephrine (NE) significantly increased at 1, 3, and 7 days post-CI compared to the sham group. The myocardial syntaxin1A mRNA and protein expression also significantly increased at 1 day post-CI compared to the sham group. However, the sepsis-induced increase in syntaxin1A returned to the baseline values at 3 and 7 days post-CI. The expressions of myocardial NET mRNA and protein were not altered at 1 day post-CI but significantly decreased at 3 days post-CI compared to the sham and 1 day post-CI groups. The immunohistochemical analyses revealed an increased localization of NET and syntaxin1A in the heart tissue sections of the 1 day post-CI group. In the CLP model of severe sepsis, the myocardial syntaxin1A mRNA protein expressions significantly increased at 2 h post-CLP, but remained unchanged at 20 h post-CLP compared to the sham group. In contrast, the myocardial expressions of NET mRNA and protein significantly decreased at both 2 and 20 h post-CLP compared to the sham group. It appears that during severe sepsis (CLP model), both the upregulation of syntaxin1A and the downregulation of NET contribute to increased concentrations of NE during the early and late stages of sepsis. 相似文献
968.
Samrat Mondol Navya R Vidya Athreya Kartik Sunagar Velu Mani Selvaraj Uma Ramakrishnan 《BMC genetics》2009,10(1):1-7
Background
Copy number variants (CNVs) have been identified in several studies to be associated with complex diseases. It is important, therefore, to understand the distribution of CNVs within and among populations. This study is the first report of a CNV map in African Americans.Results
Employing a SNP platform with greater than 500,000 SNPs, a first-generation CNV map of the African American genome was generated using DNA from 385 healthy African American individuals, and compared to a sample of 435 healthy White individuals. A total of 1362 CNVs were identified within African Americans, which included two CNV regions that were significantly different in frequency between African Americans and Whites (17q21 and 15q11). In addition, a duplication was identified in 74% of DNAs derived from cell lines that was not present in any of the whole blood derived DNAs.Conclusion
The Affymetrix 500 K array provides reliable CNV mapping information. However, using cell lines as a source of DNA may introduce artifacts. The duplication identified in high frequency in Whites and low frequency in African Americans on chromosome 17q21 reflects haplotype specific frequency differences between ancestral groups. The generation of the CNV map will be a valuable tool for identifying disease associated CNVs in African Americans. 相似文献969.
Hasmik Keshishian Terri Addona Michael Burgess D. R. Mani Xu Shi Eric Kuhn Marc S. Sabatine Robert E. Gerszten Steven A. Carr 《Molecular & cellular proteomics : MCP》2009,8(10):2339-2349
Verification of candidate biomarkers requires specific assays to selectively detect and quantify target proteins in accessible biofluids. The primary objective of verification is to screen potential biomarkers to ensure that only the highest quality candidates from the discovery phase are taken forward into preclinical validation. Because antibody reagents for a clinical grade immunoassay often exist for a small number of candidates, alternative methodologies are required to credential new and unproven candidates in a statistically viable number of serum or plasma samples. Using multiple reaction monitoring coupled with stable isotope dilution MS, we developed quantitative, multiplexed assays in plasma for six proteins of clinical relevance to cardiac injury. The process described does not require antibodies for immunoaffinity enrichment of either proteins or peptides. Limits of detection and quantitation for each signature peptide used as surrogates for the target proteins were determined by the method of standard addition using synthetic peptides and plasma from a healthy donor. Limits of quantitation ranged from 2 to 15 ng/ml for most of the target proteins. Quantitative measurements were obtained for one to two signature peptides derived from each target protein, including low abundance protein markers of cardiac injury in the nanogram/milliliter range such as the cardiac troponins. Intra- and interassay coefficients of variation were predominantly <10 and 25%, respectively. The configured multiplex assay was then used to measure levels of these proteins across three time points in six patients undergoing alcohol septal ablation for hypertrophic obstructive cardiomyopathy. These results are the first demonstration of a multiplexed, MS-based assay for detection and quantification of changes in concentration of proteins associated with cardiac injury in the low nanogram/milliliter range. Our results also demonstrate that these assays retain the necessary precision, reproducibility, and sensitivity to be applied to novel and uncharacterized candidate biomarkers for verification of proteins in blood.Discovery of disease-specific biomarkers with diagnostic and prognostic utility has become an important challenge in clinical proteomics. In general, unbiased discovery experiments often result in the confident identification of thousands of proteins, hundreds of which may vary significantly between case and control samples in small discovery studies. However, because of the stochastic sampling of proteomes in discovery “omics” experiments, a large fraction of the protein biomarkers “discovered” in these experiments are false positives arising from biological or technical variability. Clearly discovery omics experiments do not lead to biomarkers of immediate clinical utility but rather produce candidates that must be qualified and verified in larger sample sets than were used for discovery (1).Traditional, clinical validation of biomarkers has relied primarily on immunoassays because of their specificity and sensitivity for the target analyte and high throughput capability. However, antibody reagents for a clinical grade immunoassay often only exist for a short list of candidates. The development of a reliable sandwich immunoassay for one target protein is expensive, has a long development time, and is dependent upon the generation of high quality protein antibodies. For the large majority of new, unproven candidate biomarkers, an intermediate verification technology is required that has shorter assay development time lines, lower assay cost, and effective multiplexing of dozens of candidates in low sample volumes. Ideally the approach should be capable of analyzing hundreds of samples of serum or plasma with good precision. The desired outcome of verification is a small number of highly credentialed candidates suitable for traditional preclinical and clinical validation studies.Multiple reaction monitoring (MRM)1 coupled with stable isotope dilution (SID) MS has recently been shown to be well suited for direct quantification of proteins in plasma (2–4) and has emerged as the core technology for candidate biomarker verification. MRM assays can be highly multiplexed such that a moderate number of candidate proteins (in the range of 10–50) can be simultaneously targeted and measured in the statistically viable number of patient samples required for verification (hundreds of serum samples). However, sensitivity for unambiguous detection and quantification of proteins by MS-based assays is often constrained by sample complexity, particularly when the measurements are being made in complex fluids such as plasma.Many biomarkers of current clinical importance, such as prostate-specific antigen and the cardiac troponins, reside in the low nanogram/milliliter range in plasma and, until recently, have been inaccessible by non-antibody approaches. Our laboratory has recently shown for the first time that a combination of abundant protein depletion with limited fractionation at the peptide level prior to SID-MRM-MS provides robust limits of quantitation (LOQs) in the 1–20 ng/ml range with coefficient of variation (CV) of 10–20% at the LOQ for proteins in plasma (3).Here we demonstrate that this work flow can be extended to configure assays for a number of known markers of cardiovascular disease and, more importantly, can be deployed to measure their concentrations in clinical samples. We modeled a verification study comprising six patients undergoing alcohol septal ablation treatment for hypertrophic obstructive cardiomyopathy, a human model of “planned” myocardial infarction (PMI), and obtained targeted, quantitative measurements for moderate to low concentrations of cardiac biomarkers in plasma. This work provides additional evidence that MS-based assays can be configured and applied to verification of new protein targets for which high quality antibody reagents are not available. 相似文献
970.
Soumen K. Maiti Rajesh K. Srivastava Mani Bhushan Pramod P. Wangikar 《Process Biochemistry》2009,44(8):799-811
Industrial fermentations conducted in a batch or semi-batch mode demonstrate significant batch-to-batch variability. Current batch process monitoring strategies involve manual interpretation of highly informative but low frequency offline measurements such as concentrations of products, biomass and substrates. Fermentors are also fitted with computer interfaced instrumentation, enabling high frequency online measurements of several variables and automated techniques which can utilize this data would be desirable. Evolution of a batch fermentation, which typically uses complex medium, can be conceptualized as a sequence of several distinct metabolic phases. Monitoring of batch processes can then be achieved by detecting the phase change events, also termed as singular points (SP). In this work, we propose a novel moving window based real-time monitoring strategy for SP detection based only on online measurements. The key hypothesis of the strategy is that the statistical properties of the online data undergo a significant change around an SP. The strategy is easily implementable and does not require past data or prior knowledge of the number or time of occurrence of SPs. The efficacy of the proposed approach has been demonstrated to be superior compared to that of reported techniques for industrially relevant model organisms. The proposed approach can be used to decide offline sampling timings in real time. 相似文献