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31.
32.
Kar A Saha D Purohit G Singh A Kumar P Yadav VK Kumar P Thakur RK Chowdhury S 《Nucleic acids research》2012,40(6):2554-2565
Analysis of chromatin-immunoprecipitation followed by sequencing (ChIP-seq) usually disregards sequence reads that do not map within binding positions (peaks). Using an unbiased approach, we analysed all reads, both that mapped and ones that were not included as part of peaks. ChIP-seq experiments were performed in human lung adenocarcinoma and fibrosarcoma cells for the metastasis suppressor non-metastatic 2 (NME2). Surprisingly, we identified sequence reads that uniquely represented human telomere ends in both cases. In vivo presence of NME2 at telomere ends was validated using independent methods and as further evidence we found intranuclear association of NME2 and the telomere repeat binding factor 2. Most remarkably, results demonstrate that NME2 associates with telomerase and reduces telomerase activity in vitro and in vivo, and sustained NME2 expression resulted in reduced telomere length in aggressive human cancer cells. Anti-metastatic function of NME2 has been demonstrated in human cancers, however, mechanisms are poorly understood. Together, findings reported here suggest a novel role for NME2 as a telomere binding protein that can alter telomerase function and telomere length. This presents an opportunity to investigate telomere-related interactions in metastasis suppression. 相似文献
33.
Metalworking fluids (MWFs) are complex mixtures of chemicals and are indispensable materials in industry. They are used as cooling and lubricating agents in different machining process such as grinding, milling, and cutting. The quality of MWFs is affected by physical, chemical, and microbial contaminates. In particular, MWFs are highly vulnerable to microbial contamination, which may act both as potential pathogens and deteriorgens. Microbial contamination is of major concern due to potential health hazards such as skin dermatitis and hypersensitivity pneumonitis. The contaminated MWFs can exhibit high degrees of microbial loading, ranging from 10(4) to 10(10) colony-forming units (CFU)/ml. Wide varieties of microorganisms are reported to colonize MWFs. Traditional culturing techniques are not only laborious and time consuming but also underestimate the actual distribution of the microorganisms present in the contaminated MWFs. Therefore, rapid molecular methods such as real-time PCR and fluorescent in situ hybridization are implemented to monitor the microbial load. In industry, biocides are presently used to control microbial contamination. However, it has its own disadvantages and therefore, in recent years, alternative methods such as UV irradiation were evaluated to reduce microbial contamination in MWFs. Microbes inhabiting the MWF are also capable of forming biofilm which is detrimental to the MWF system. Biofilm is resistant to common disinfectant methods, and thus further research and development is required to effectively control its formation within MWF systems. This review is intended to discuss the overall microbiological aspects of MWF. 相似文献
34.
Psoriasis is a chronic, autoimmune skin disease affecting approximately 2% of the world's population. Clobetasol propionate
which is a superpotent topical corticosteroid is widely used for topical treatment of psoriasis. Conventional dosage forms
like creams and ointments are commonly prefered for the therapy. The purpose of this study was to develop a new topical delivery
system in order to provide the prolonged release of clobetasol propionate and to reduce systemic absorption and side effects
of the drug. Clobetasol propionate loaded-poly(D,L-lactic-co-glycolic acid) (PLGA) microspheres were prepared by oil-in-water
emulsion–solvent evaporation technique. Particle size analysis, morphological characterization, DSC and XRD analyses and in vitro drug release studies were performed on the microparticle formulations. Emulgel formulations were prepared as an alternative
for topical delivery of clobetasol propionate. In vitro drug release studies were carried out from the emulgel formulations containing pure drug and drug-loaded microspheres. In
addition, the same studies were performed to determine the drug release from the commercial cream product of clobetasol propionate.
The release of clobetasol propionate from the emulgel formulations was significantly higher than the commercial product. In
addition, the encapsulation of clobetasol propionate in the PLGA microspheres significantly delayed the drug release from
the emulgel formulation. As a result, the decrease in the side effects of clobetasol propionate by the formulation containing
PLGA microspheres is expected. 相似文献
35.
Jianping P. Wang Suleiman S. Bughrara Rouf M. A. Mian Malay C. Saha David A. Sleper 《Molecular breeding : new strategies in plant improvement》2009,23(2):299-309
Intergeneric hybridization between Festuca and Lolium has been a long-term goal of forage and turfgrass breeders to generate improved cultivars by combining stress tolerance of
Festuca and rapid establishment of Lolium. However, wide-distance hybridizations usually result in the wild genome being eliminated from the hybrid due to incomplete
chromosome pairing and crossovers. In this study, random amplified polymorphic DNA (RAPD) and simple sequence repeat (SSR)
markers were used to detect the parental genome composition of F1 hybrids and backcross, generated from crosses between Festuca mairei St. Yves (Fm) and Lolium perenne L. (Lp). Each of the hybrids exhibited integration of Fm and Lp genomes with varying levels of Fm/Lp genome ratios. However,
cluster and principle component analyses of the progeny consistently revealed four groups depending on the amount of genome
introgression from both parents. The parental genome composition and classifications of intergeneric progeny would be useful
for breeding material selection.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
36.
Hughes SR Gibbons WR Bang SS Pinkelman R Bischoff KM Slininger PJ Qureshi N Kurtzman CP Liu S Saha BC Jackson JS Cotta MA Rich JO Javers JE 《Journal of industrial microbiology & biotechnology》2012,39(1):163-173
Scheffersomyces (formerly Pichia) stipitis NRRL Y-7124 was mutagenized using UV-C irradiation to produce yeast strains for anaerobic conversion of lignocellulosic sugars to ethanol. UV-C irradiation potentially produces large numbers of random mutations broadly and uniformly over the whole genome to generate unique strains. Wild-type cultures of S. stipitis NRRL Y-7124 were subjected to UV-C (234 nm) irradiation targeted at approximately 40% cell survival. When surviving cells were selected in sufficient numbers via automated plating strategies and cultured anaerobically on xylose medium for 5 months at 28°C, five novel mutagenized S. stipitis strains were obtained. Variable number tandem repeat analysis revealed that mutations had occurred in the genome, which may have produced genes that allowed the anaerobic utilization of xylose. The mutagenized strains were capable of growing anaerobically on xylose/glucose substrate with higher ethanol production during 250- to 500-h growth than a Saccharomyces cerevisiae yeast strain that is the standard for industrial fuel ethanol production. The S. stipitis strains resulting from this intense multigene mutagenesis strategy have potential application in industrial fuel ethanol production from lignocellulosic hydrolysates. 相似文献
37.
Amit K. Halder Achintya Saha Krishna Das Saha 《Journal of biomolecular structure & dynamics》2013,31(8):1756-1779
Inhibitors of poly (ADP-ribose) polymerase-1 (PARP-1) enzyme are useful for the treatment of various diseases including cancer. Comparative in silico studies were performed on different ligand-based (2D-QSAR, Kernel-based partial least square (KPLS) analysis, Pharmacophore Search Engine (PHASE) pharmacophore mapping), and structure-based (molecular docking, MM-GBSA analyses, Gaussian-based 3D-QSAR analyses on docked poses) modeling techniques to explore the structure–activity relationship of a diverse set of PARP-1 inhibitors. Two-dimensional (2D)-QSAR highlighted the importance of charge topological index (JGI7), fractional polar surface area (JursFPSA3), and connectivity index (CIC2) along with different molecular fragments. Favorable and unfavorable fingerprints were demonstrated in KPLS analysis, whereas important pharmacophore features (one acceptor, one donor, and two ring aromatic) along with favorable and unfavorable field effects were demonstrated in PHASE-based pharmacophore model. MM-GBSA analyses revealed significance of different polar, non-polar, and solvation energies. Docking-based alignment of ligands was used to perform Gaussian-based 3D-QSAR study that further demonstrated importance of different field effects. Overall, it was found that polar interactions (hydrogen bonding, bridged hydrogen bonding, and pi–cation) play major roles for higher activity. Steric groups increase the total contact surface area but it should have higher fractional polar surface area to adjust solvation energy. Structure-based pharmacophore mapping spotted the positive ionizable feature of ligands as the most important feature for discriminating highly active compounds from inactives. Molecular dynamics simulation, conducted on highly active ligands, described the dynamic behaviors of the protein complexes and supported the interpretations obtained from other modeling analyses. The current study may be useful for designing PARP-1 inhibitors. 相似文献
38.
39.
A multi-channel sandwich microgravimetric immunoassay (sMIA), using the quartz crystal microbalance (QCM) principle, has been developed to quantify low molecular weight substances in standard solutions. An antigen is sandwiched between two antigen-specific antibodies: the first antibody is coated on the quartz crystal surface and the second antibody is used for the detection of analyte. The concentration of low molecular weight antigen (insulin was used in this study, M
r6000 Da) was correlated with the shift of resonant frequency of QCM system before and after second antibody binding to insulin. The developed assay is highly specific showing low cross-reactivity, and is sensitive to approx. 1 ng insulin ml–1 with a linear response for insulin from 10 g ml–1 to 10 ng ml–1 in standard solutions. The technique may also be applied for the detection of other small biomolecules. 相似文献
40.
An annotated checklist of Culicoides Latreille, 1809 (Insecta: Ceratopogonidae: Diptera) with incorporation of a vector species list from India 下载免费PDF全文
Emon Mukhopadhyay Abhijit Mazumdar S.N. Joardar Goutam K. Saha Dhriti Banerjee 《Journal of vector ecology》2016,41(2):279-284
Culicoides Latreille, 1809 (Insecta : Diptera : Ceratopogonidae) are small nematocerous biological vectors of a wide range of pathogens of veterinary and medical importance. They are distributed worldwide but prefer warm, damp, and muddy areas. Female midges require blood for egg maturation. Studies on taxonomy, proper identification keys, and distribution patterns of these flies across different geographical regions of India of these flies are limited. This article provides an updated checklist of Culicoides spp. from India collected from various scattered publications, along with their synonyms and details on their subgenera, geographical distribution, and type locality. A compiled list of different Culicoides vectors from India has also been included separately in this article, along with the type of the diseases spread. 相似文献