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91.
Banerjee S Kambhampati S Haque I Banerjee SK 《Journal of cell communication and signaling》2011,5(4):317-324
It is estimated that one in eight women will be affected with cancer during their lives, which means over 1 million women
worldwide will be diagnosed with breast cancer in the year of 2011. Roughly, 70% of breast cancer will be estrogen receptor-alpha
(ER-α) positive. The presence of ER-α is associated with better prognosis and is able to determine if tumors will respond
to the estrogen-blocking/ER-antagonist drug Tamoxifen (TAM). However, a significant fraction of ER-positive tumors respond
with minimal or no response to TAM. It is unclear why some breast cancer cells resist TAM and how to make these cells respond.
Early evidence suggests Pomegranate fruit extracts (PFEs) exhibit an anticancer effect against some cancers. The objective
of the study was to determine whether PFEs may able to enhance/sensitize the TAM’s effect in ER-positive MCF-7 breast cancer
cells. To test the hypothesis, we determined the effect of PFEs on sensitive and TAM-resistant-MCF-7 cell viability and cell
death in the presence or absence of TAM under estrogenic or non-estrogenic culture environment. The present studies demonstrated
that PFEs enhance the TAM action in both sensitive and TAM-resistant MCF-7 cells through the inhibition of cell viability
(regular or estrogen-induced) by inducing cell-death machinery. Collectively, the results showed for the first time that pomegranate
combined with TAM may represent a novel and a powerful approach to enhance and sensitize TAM action. 相似文献
92.
Shah V Shah S Kambhampati MS Ambrose J Smith N Dowd SE McDonnell KT Panigrahi B Green T 《PloS one》2011,6(10):e26263
Of the few preserved areas in the northeast of United States, the soil in the Pine Barrens Forests presents a harsh environment for the microorganisms to grow and survive. In the current study we report the use of clustering methods to scientifically select the sampling locations that would represent the entire forest and also report the microbial diversity present in various horizons of the soil. Sixty six sampling locations were selected across the forest and soils were collected from three horizons (sampling depths). The three horizons were 0-10 cm (Horizon O); 11-25 cm (Horizon A) and 26-40 cm (Horizon B). Based on the total microbial substrate utilization pattern and K-means clustering analysis, the soil in the Pine Barrens Forest can be classified into four distinct clusters at each of the three horizons. One soil sample from each of the four clusters were selected and archaeal and bacterial populations within the soil studied using pyrosequencing method. The results show the microbial communities present in each of these clusters are different. Within the microbial communities present, microorganisms involved in nitrogen cycle occupy a major fraction of microbial community in the soil. High level of diversity was observed for nitrogen fixing bacteria. In contrast, Nitrosovibrio and Nitrosocaldus spp are the single bacterial and archaeal population respectively carrying out ammonia oxidation in the soil. 相似文献
93.
Amitabh Singh Sudarshan Maurya Rashmi Singh U.P. Singh 《Archives Of Phytopathology And Plant Protection》2013,46(14):1655-1662
High performance liquid chromatographic (HPLC) analysis of culture filtrates of plant growth promoting rhizobacteria (PGPR) and medium of inhibitory zone of interaction of Sclerotium rolfsii with PGPR, viz. Pseudomonas aeruginosa, Pseudomonas fluorescens 4, Pseudomonas fluorescens 4 (new) and Pseudomonas sp. varied from sample to sample. In all the culture filtrates of PGPRs, P. aeruginosa had nine phenolic acids in which ferulic acid (14.52 μg/ml) was maximum followed by other phenolic acids. However, the culture filtrates of P. fluorescens 4 had six phenolic acids with maximum ferulic acid (20.54 μg/ml) followed by indole acetic acid (IAA), caffeic, salicylic, o-coumeric acid and cinnamic acids. However, P. fluorescens 4 culture filtrate had seven phenolic acids in which salicylic acid was maximum (18.03 μg) followed by IAA, caffeic, vanillic, ferulic, o-coumeric and cinnamic acids. Pseudomonas sp. also showed eight phenolic acids where caffeic acid (2.75 μg) was maximum followed by trace amounts of ferulic, salicylic, IAA, vanillic, cinnamic, o-coumeric and tannic acids. The analysis of antibiosis zone of PGPRs showed fairly rich phenolic acids. A total of nine phenolic acids were detected in which caffeic acid was maximum (29.14 μg/g) followed by gallic (17.64 μg/g) and vanillic (3.52 μg/g) acids but others were in traces. In P. aeruginosa, antibiosis zone had seven phenolic acids where IAA was maximum (3.48 μg/g) followed by o-coumeric acid (2.08 μg/g), others were in traces. The medium of antibiosis zone of P. fluorescens 4 and P. fluorescens 4 new had eight phenolic acids in which IAA was maximum with other phenolic acids in traces. 相似文献
94.
U. P. Singh Leena Gohain Amitabh Singh S. Maurya S. Sahni 《Archives Of Phytopathology And Plant Protection》2013,46(2):160-167
High performance liquid chromatographic (HPLC) analysis of mycelia of Sclerotium rolfsii grown on neem cake, and Zephyarenthes citrina bulb incorporated media was carried out. Several phenoloic acids, e.g., gallic, tannic, caffeic, cinnamic, chlorogenic and O-coumeric acids, were found in considerable amounts in treated mycelial mat as compared to the control. The amount of phenloic acids increased with increased concentration of both the materials in mycelia of 7 and 14 day-old cultures. Due to anti-oxidant and several other properties of phenolic acids, the senescence of the fungus has been prolonged which may be one probable reason of sustaining the virulence of the pathogen. 相似文献
95.
D. P. Singh Amar Bahadur B. K. Sarma S. Maurya H. B. Singh U. P. Singh 《Archives Of Phytopathology And Plant Protection》2013,46(15):1454-1462
Phenylalanine ammonia lyase (PAL) activity was measured using HPLC in pea leaves following exogenous application of L-phenylalanine and ferulic acid. Treatment with different concentrations (50, 100, 150 ppm) of L-phenylalanine caused increased activity of PAL activity in comparison to control. In pea leaves treated with 50 ppm L-phenylalanine, maximum PAL activity was observed after 72 h of treatment. Application of ferulic acid first reduced PAL activity at lower concentration (50 ppm) but it further increased at higher concentrations of the compound (100 and 150 ppm) in pea leaves compared to control. Minimum PAL activity was 0.19 nM cinnamic acid/min/g fresh wt after 24 h at 50 ppm and then increased with time. Treatment with both compounds significantly increased the accumulation of phenolic acids and salicylic acid and reduced conidial germination of Erysiphe pisi on pea leaves. They were equally effective at 100 and 150 ppm in reducing conidial germination. Conidial germination on L-phenylalanine-treated leaves was 26% after 24 h and that on ferulic acid treated leaves 34% compared to control (46%). Foliar application of different concentrations of L-phenylalanine increased the level of ferulic acid in the leaves of pea plants. Maximum enzyme activity in terms of the accumulation of cinnamic acid (79.3 and 83.5 μg/g fresh wt) was observed following the application of L-phenylalanine after 24 and 48 h respectively. At 50 ppm, cinnamic acid accumulation in pea leaves was 35.6 and 39.4 μg/g fresh wt and 74.3 and 86.5 μg/g fresh wt at 100 ppm. 相似文献
96.
Sudarshan Maurya Ritesh Kumar J.S. Choudhary Bikash Das S. Kumar 《Archives Of Phytopathology And Plant Protection》2013,46(18):2278-2280
An anamorphic entomopathogenic fungus Neozygites sp. belonging to the Family Neozygitaceae was found infecting the tetranychid mites Tetranychus urticae Koch (Acari: Tetranychidae) of French bean (Phaseolus vulgaris L.) for the first time in Eastern Plateau and Hill region of India in the month of October 2011. The report of entomopathogenic fungus could be of help in managing acaricide resistant mites. 相似文献
97.
Sunil Bala Wesley Devendra Prasad Maurya Hari Sharan Goyal Sangeeta Negi 《World journal of microbiology & biotechnology》2013,29(12):2353-2357
In the current study, ferritic stainless grades AISI 439 and AISI 444 were investigated as possible construction materials for machinery and equipment in the cane-sugar industry. Their performance in corrosive cane-sugar juice environment was compared with the presently used low carbon steel AISI 1010 and austenitic stainless steel AISI 304. The Tafel plot electrochemical technique was used to evaluate general corrosion performance. Microbiologically influenced corrosion (MIC) behaviour in sugarcane juice environment was studied. Four microbial colonies were isolated from the biofilms on the metal coupon surfaces on the basis of their different morphology. These were characterized as Brevibacillus parabrevis, Bacillus azotoformans, Paenibacillus lautus and Micrococcus sp. The results of SEM micrographs showed that AISI 439 and AISI 304 grades had suffered maximum localized corrosion. MIC investigations revealed that AISI 444 steel had the best corrosion resistance among the tested materials. However from the Tafel plots it was evident that AISI 1010 had the least corrosion resistance and AISI 439 the best corrosion resistance. 相似文献
98.
Shreya Dubey Suneel Kumar Madana Monika Kallubai Arijit Sarkar 《Journal of biomolecular structure & dynamics》2020,38(7):1927-1937
AbstractMost of the drugs binding to human serum albumin (HSA) are transported to various parts of the body. Here, we have studied the molecular interaction between HSA and synthesized uridine derivatives, 1-[(3R, 4S, 5?R)-2-methyl-3, 4-dihydroxy-5-(hydroxymethyl)oxolan-2-yl]pyrimidine-2,4-dion.)(C-MU); [(2R,3R,4R,5R)-5-(2,4-dioxo-3,4-dihydropyrimidin-1(2H)-yl)-3,4-dihydroxy-4-methyl-tetrahydrofuran-2-yl] methyl methyl phosphochloridate (CM-MU) and [(2R,3S,4R,5R)-5-(2,4-dioxopyrimidin-1-yl)-2-methyl-3,4-dihydroxyoxolan-2-yl] methyl dihydrogen phosphate (P-MU). Cytotoxic studies of these synthesized compounds with mouse macrophages (RAW 246.7) and HeLa cells (human cervical cancer cells) and binding mechanism of these uridine derivatives with HSA were performed. Subsequently, fluorescence quenching was observed upon titration of uridine derivatives with HSA via static mode of quenching, and the binding constants (K2-C-MU = 4?±?0.03?×?104M?1, K5-CM-MU = 1.95?±?0.03?×?104 M?1 and K5-P-MU =1.56?±?0.03?×?104 M?1) were found to be in sync with the computational results. Further, molecular displacement and molecular docking data revealed that all the derivatives are binding in the subdomain IIA and IIB regions of HSA. The protein secondary structure of complexes was determined by circular dichroism, indicating partial unfolding of the protein upon addition of the uridine derivatives. Furthermore, atomic force microscopy data reveal the change in topology upon binding of 2-C-MU, 5-CM-MU and 5-P-MU with HSA, indicating change in the microenvironment around tryptophan region. Additionally, cytotoxicity studies on HeLa and Raw Cell lines suggested that these molecules have significant anti-proliferative and anti-inflammatory properties. Hence, the study may be of help for development of new drugs based on uridine derivatives which may be helpful for combating various potential diseases.Communicated by Ramaswamy H. Sarma 相似文献
99.
Cellophane touch tape preparation provides reproducible results in minimal time when compared to tease mount and slide culture techniques for the identification of fungi from culture plates, but it is difficult to perform from tube cultures. Here, we describe an easy to perform touch tape preparation method that provided a better result from fungal tube culture. 相似文献
100.
Yadav DK Gautam AK Kureel J Srivastava K Sahai M Singh D Chattopadhyay N Maurya R 《Bioorganic & medicinal chemistry letters》2011,21(2):677-681
A series of didzein derivatives were synthesized and assessed for stimulation of osteoblast differentiation using primary cultures of rat calvarial osteoblasts. Data suggested that three synthetic analogs, 1c, 3a and 3c were several folds more potent than daidzein in stimulating differentiation and mineralization of osteoblasts. Further, these three compounds did not show any estrogen agonistic activity, however had mild estrogen antagonistic effect. Out of the three compounds, 3c was found to maximally increase the mineralization of bone marrow osteoprogenitor cells. Compound 3c also robustly increased the mRNA levels of osteogenic genes including bone morphogenetic protein-2 and osteocalcin in osteoblasts. Unlike daidzein, 3c did not inhibit osteoclastogenesis. Collectively, we demonstrate osteogenic activity of daidzein analogs at significantly lower concentrations than daidzein. 相似文献