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1.
Amal Bhattacharya Mrinal Ghosh Amalesh Choudhury 《The Journal of eukaryotic microbiology》1987,34(4):403-405
Acanthamoeba rhysodes has been found to be a predominant intertidal benthic gymnamoeba in the mangrove ecosystem of Sundarbans of lower deltaic Bengal, facing the Bay. The sampling zones under study were the highest high tide regions, with characteristic mangrove litter-soil, inundated twice per month during the highest ebb of spring tide. Population abundance of this species, both in its trophic and cystic forms in the three distinct seasonal periods of pre-monsoon (March to June), monsoon (July to October), and post-monsoon (November to February) has been surveyed for over two years. These seasonal periods affect the physico-chemical parameters of the habitat substrata, including temperature, pH, and salinity. It has been found that the overall number of organisms per gram of soil attains peak value during the monsoon period. This value comes down in post-monsoon samples and is the least in pre-monsoon ones. 相似文献
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Recently, we have developed a high-resolution two-dimensional separation strategy for the analysis of complex peptide mixtures. This methodology employs isoelectric focusing of peptides on immobilized pH gradient (IPG) gels in the first dimension, followed by reversed-phase chromatography in the second dimension, and subsequent tandem mass spectrometry analysis. The traditional approach to this mixture problem employs strong-cation-exchange (SCX) chromatography in the first dimension. Here, we present a direct comparison of these two first-dimensional techniques using complex protein samples derived from the testis of Rattus norvegicus. It was found that the use of immobilized pH gradients (narrow range pH 3.5-4.5) for peptide separation in the first dimension yielded 13% more protein identifications than the optimized off-line SCX approach (employing the entire pI range of the sample). In addition, the IPG technique allows for a much more efficient use on mass spectrometer analysis time. Separation of a tryptic digest derived from a rat testis sample on a narrow range pH gradient (over the 3.5-4.5 pH range) yielded 7626 and 2750 peptides and proteins, respectively. Peptide and protein identification was performed with high confidence using SEQUEST in combination with a data filtering program employing pI and statistical based functions to remove false-positives from the data. 相似文献
4.
Olfat Shaker Amal El‐Shehaby Salwa Fayez Amr Zahra Samar Marzouk Maissa El Raziky 《Cell biochemistry and function》2013,31(7):620-625
This study aimed to determine the relationship between osteopontin gene polymorphisms and its protein level and the efficacy of interferon‐based therapies in Hepatitis C virus (HCV) patients. Hundreds HCV patients genotype 4, treated with pegylated interferon alfa‐2b plus ribavirin and 60 healthy subjects were enrolled. All individuals were subjected to clinical and laboratory parameters, including hepatitis markers and HCV quantitation by real‐time polymerase chain reaction. Single nucleotide polymorphisms (SNPs) of osteopontin (OPN) gene (nucleotide ?155, ?443 and ?1748) were analysed by direct sequencing in addition to estimation of serum level of OPN. SNP at ?443 (C/C versus C/T, T/T) was found to represent predictors for treatment response by univariate logistic regression analysis. OPN serum level was independent predictors for treatment response by both univariate and multivariate logistic regression analysis. SNP at nucleotide ?443 and serum OPN protein levels could be used as useful markers to predict the efficacy of treatment. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Chandan K. Maiti Surjit Sen Amal Kanti Paul 《Archives Of Phytopathology And Plant Protection》2013,46(7):796-805
Withania somnifera (L.) Dunal, also known Indian ginseng is one of the most widespread tranquillizers tranquillisers used for the treatment of nervous disorders, intestinal infection, leprosy, and cancer; it also suffers a leaf blight disease caused by the fungus Alternaria dianthicola in various districts of South Bengal, India: Pseudomonas aeruginosa strain WS-1 isolated from the rhizosphere, showed both in vitro and in vivo antagonistic activity against the pathogen. The antifungal activity of the isolate has been found to be linked to theproduction of a siderophore, volatile substances (hydrocyanic acid), proteases and chitinases. Foliar application of a talc talc-based formulation of P. aeruginosa strain WS-1 to field grown W. somnifera reduced disease severity by 80% compared to non-treated control. 相似文献
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Olson SD Pollock K Kambal A Cary W Mitchell GM Tempkin J Stewart H McGee J Bauer G Kim HS Tempkin T Wheelock V Annett G Dunbar G Nolta JA 《Molecular neurobiology》2012,45(1):87-98
There is much interest in the use of mesenchymal stem cells/marrow stromal cells (MSC) to treat neurodegenerative disorders, in particular those that are fatal and difficult to treat, such as Huntington's disease. MSC present a promising tool for cell therapy and are currently being tested in FDA-approved phase I-III clinical trials for many disorders. In preclinical studies of neurodegenerative disorders, MSC have demonstrated efficacy, when used as delivery vehicles for neural growth factors. A number of investigators have examined the potential benefits of innate MSC-secreted trophic support and augmented growth factors to support injured neurons. These include overexpression of brain-derived neurotrophic factor and glial-derived neurotrophic factor, using genetically engineered MSC as a vehicle to deliver the cytokines directly into the microenvironment. Proposed regenerative approaches to neurological diseases using MSC include cell therapies in which cells are delivered via intracerebral or intrathecal injection. Upon transplantation, MSC in the brain promote endogenous neuronal growth, encourage synaptic connection from damaged neurons, decrease apoptosis, reduce levels of free radicals, and regulate inflammation. These abilities are primarily modulated through paracrine actions. Clinical trials for MSC injection into the central nervous system to treat amyotrophic lateral sclerosis, traumatic brain injury, and stroke are currently ongoing. The current data in support of applying MSC-based cellular therapies to the treatment of Huntington's disease is discussed. 相似文献
8.
Length–weight relationships of seven fish species from the upper Pelus River,Kuala Kangsar district,Perak, Malaysia 下载免费PDF全文
M. E. M. Ikhwanuddin M. N. A. Amal S. Shohaimi A. Azizul S. Johari T. Abdullah N. R. Jamil 《Zeitschrift fur angewandte Ichthyologie》2016,32(3):511-512
Length–weight relationships (LWR) are reported for seven fish species from the upper Pelus River, Kuala Kangsar district, Perak, Malaysia. This river is located in a remote area and supplies fishes for the aboriginal peoples. Fish samplings were conducted in three different seasons, the dry (June 2014), wet (August 2014), and moderately wet (April 2015). All samples were collected using fish electro–shocker and scoop nets with a 1 cm mesh size. A total of seven LWRs were unknown to FishBase, and four new maximum fish lengths were identified in the study. 相似文献
9.
The genes involved in DNA repair system play a crucial role in the protection against mutations. It has been hypothesized
that functional deficiencies in highly conserved DNA repair processes resulting from polymorphic variation may increase genetic
susceptibility to breast cancer (BC). The aim of the present study was to evaluate the association of genetic polymorphisms
in 2 DNA repair genes, XPD (Asp312Asn) and XRCC1 (A399G), with BC susceptibility. We further investigated the potential combined
effect of these DNA repair variants on BC risk. Both XPD (xeroderma pigmentosum group D) and XRCC1 (X-ray repair cross-complementing
group 1) polymorphisms were characterized in 100 BC Egyptian females and 100 healthy women who had no history of any malignancy
by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) method and PCR with confronting two-pair
primers (PCR-CTPP), using DNA from peripheral blood in a case control study. Our results revealed that the frequencies of
AA genotype of XPD codon 312 polymorphism were significantly higher in the BC patients than in the normal individuals (P ≤ 0.003), and did not observe any association between the XRCC1 Arg399Gln polymorphism and risk of developing BC. Also, no
association between both XPD Asp312Asn and XRCC1 A399G polymorphisms and the clinical characteristics of disease. Finally,
the combination of AA(XPD) + AG(XRCC1) were significantly associated with BC risk. Our results suggested that, XPD gene is
an important candidate gene for susceptibility to BC. Also, gene–gene interaction between XPD(AA) + XRCC1(AG) polymorphism
may be associated with increased risk of BC in Egyptian women. 相似文献
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