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161.
Andrew G. Cridge Jyothsna Visweswaraiah Rashmi Ramesh Evelyn Sattlegger 《Analytical biochemistry》2014
This work describes a quick semi-quantitative colony immunoassay (QSCI) method for immunoblot detection of intracellularly expressed proteins in both yeast and bacterial cells. After induction of protein expression, only 4.5 h is required for cell breakage, protein detection, and data analysis. This protocol was used to screen and unambiguously identify Saccharomyces cerevisiae cells efficiently overexpressing glutathione S-transferase (GST)-tagged Yih1 in addition to cells expressing the myc-tagged large 297-kDa Gcn1 protein. In addition, the method was used to identify Escherichia coli cells efficiently expressing His6-tagged Yih1 and a GST-tagged Gcn1 fragment, respectively. The protocol allows the use of both epitope-specific and protein-specific antibodies. The same colony immunoassay can also be used to determine the minimal concentration of inducing agent sufficient for induction of optimal protein expression (e.g., galactose for yeast, isopropyl β-d-1-thiogalactopyranoside [IPTG] for E. coli). To our knowledge, this is the first report on a rapid low-cost procedure that allows the calibration of inducing agent on solid medium. 相似文献
162.
Yolanda Stypula-Cyrus Nikhil N. Mutyal Mart Dela Cruz Dhananjay P. Kunte Andrew J. Radosevich Ramesh Wali Hemant K. Roy Vadim Backman 《FEBS letters》2014
End-binding protein (EB1) is a microtubule protein that binds to the tumor suppressor adenomatous polyposis coli (APC). While EB1 is implicated as a potential oncogene, its role in cancer progression is unknown. Therefore, we analyzed EB1/APC expression at the earliest stages of colorectal carcinogenesis and in the uninvolved mucosa (“field effect”) of human and animal tissue. We also performed siRNA-knockdown in colon cancer cell lines. EB1 is up-regulated in early and field carcinogenesis in the colon, and the cellular/nano-architectural effect of EB1 knockdown depended on the genetic context. Thus, dysregulation of EB1 is an important early event in colon carcinogenesis. 相似文献
163.
Vessela D. Kancheva Luciano Saso Petya V. Boranova Abdullah Khan Manju K. Saroj Mukesh K. Pandey Shashwat Malhotra Jordan Z. Nechev Sunil K. Sharma Ashok K. Prasad Maya B. Georgieva Carleta Joseph Anthony L. DePass Ramesh C. Rastogi Virinder S. Parmar 《Biochimie》2010
The chain-breaking antioxidant activities of eight coumarins [7-hydroxy-4-methylcoumarin (1), 5,7-dihydroxy-4-methylcoumarin (2), 6,7-dihydroxy-4-methylcoumarin (3), 6,7-dihydroxycoumarin (4), 7,8-dihydroxy-4-methylcoumarin (5), ethyl 2-(7,8-dihydroxy-4-methylcoumar-3-yl)-acetate (6), 7,8-diacetoxy-4-methylcoumarin (7) and ethyl 2-(7,8-diacetoxy-4-methylcoumar-3-yl)-acetate (8)] during bulk lipid autoxidation at 37 °C and 80 °C in concentrations of 0.01–1.0 mM and their radical scavenging activities at 25 °C using TLC–DPPH test have been studied and compared. It has been found that the o-dihydroxycoumarins 3–6 demonstrated excellent activity as antioxidants and radical scavengers, much better than the m-dihydroxy analogue 2 and the monohydroxycoumarin 1. The substitution at the C-3 position did not have any effect either on the chain-breaking antioxidant activity or on the radical scavenging activity of the 7,8-dihydroxy- and 7,8-diacetoxy-4-methylcoumarins 6 and 8. The comparison with DL-α-tocopherol (TOH), caffeic acid (CA) and p-coumaric acid (p-CumA) showed that antioxidant efficiency decreases in the following sequence: 相似文献
164.
Sudhakar Baluchamy Ye Zhang Prabakaran Ravichandran Vani Ramesh Ayodotun Sodipe Joseph C. Hall Olufisayo Jejelowo Daila S. Gridley Honglu Wu Govindarajan T. Ramesh 《Molecular and cellular biochemistry》2010,341(1-2):207-215
Exposure of living systems to radiation results in a wide assortment of lesions, the most significant of is damage to genomic DNA which alter specific cell functions including cell proliferation. The radiation induced DNA damage investigation is one of the important area in biology, but still the information available regarding the effects of proton is very limited. In this report, we investigated the differential gene expression pattern of DNA damage signaling genes such as damaged DNA binding, repair, cell cycle arrest, checkpoints and apoptosis using quantitative real-time RT-PCR in proton exposed mouse brain tissues. The expression profiles showed significant changes in DNA damage related genes in 2 Gy proton exposed mouse brain tissues as compared to control brain tissues. Furthermore, we also show that significantly increased levels of apoptotic related genes, caspase-3 and 8 activities in these cells, suggesting that in addition to differential expression of DNA damage genes, the alteration of apoptosis related genes may also contribute to the radiation induced DNA damage followed by programmed cell death. In summary, our findings suggest that proton exposed cells undergo severe DNA damage which in turn destabilize the chromatin stability. 相似文献
165.
Biswajit Mishra Vipul Kumar Srivastava Rama Chaudhry Rishi Kumar Somvanshi Abhay Kumar Singh Kamaldeep Gill Ramesh Somvanshi Ishan Kumar Patro Sharmistha Dey 《Amino acids》2010,39(5):1493-1505
Anti-bacterial drug resistance is one of the most critical concerns among the scientist worldwide. The novel antimicrobial
decapeptide SD-8 is designed and its minimal inhibitory concentration and therapeutic index (TI) was found in the range of
1–8 μg/ml and 45–360, respectively, against major group of Gram positive pathogens (GPP). The peptide was also found to be
least hemolytic at a concentration of 180 μg/ml, i.e., nearly 77 times higher than its average effective concentration. The
kinetics assay showed that the killing time is 120 min for methicillin-sensitive Staphylococcus aureus (MSSA) and 90 min for methicillin-resistant S. aureus (MRSA). Membrane permeabilization is the cause of peptide antimicrobial activity as shown by the transmission electron microscopy
studies. The peptide showed the anti-inflammatory property by inhibiting COX-2 with a K
D and K
i values of 2.36 × 10−9 and 4.8 × 10−8 M, respectively. The peptide was also found to be effective in vivo as derived from histopathological observations in a Staphylococcal
skin infection rat model with MRSA as causative organism. 相似文献
166.
Mahula (Madhuca latifolia L.) is a deciduous tree commonly found in the tropical rain forests of Asian and Australian continent. Corolla, the edible
part of its flowers, is rich in fermentable sugar (37 ± 0.23%; on dry weight basis). Batch fermentation of mahula flowers
was carried out using Zymomonas mobilis MTCC 92 free cells and cells immobilized in calcium alginate matrix. The ethanol productions were 122.9 ± 0.972 and 134.6
± 0.104 g/kg flowers on dry weight basis using free and immobilized cells, respectively, after 96 h of fermentation, which
showed that cells entrapped in calcium alginate matrix yielded 8.7% more ethanol than free cells. Further, the immobilized
cells were physiologically active up to three more cycles of fermentation producing 132.7 ± 0.095, 130.5 ± 0.09 and 128.7
± 0.056 g ethanol per kg flower in first, second and third cycle, respectively. 相似文献
167.
Kulbhushansingh Ramesh Suryawanshi Yash Veer Bhatnagar Charudutt Mishra 《Oecologia》2010,162(2):453-462
Many mammalian herbivores show a temporal diet variation between graminoid-dominated and browse-dominated diets. We determined
the causes of such a diet shift and its implications for conservation of a medium-sized ungulate—the bharal Pseudois nayaur. Past studies show that the bharal diet is dominated by graminoids (>80%) during summer, but the contribution of graminoids
declines to about 50% in winter. We tested the predictions generated by two alternative hypotheses explaining the decline:
low graminoid availability during winter causes bharal to include browse in their diet; bharal include browse, with relatively
higher nutritional quality, in their diet to compensate for the poor quality of graminoids during winter. We measured winter
graminoid availability in areas with no livestock grazing, areas with relatively moderate livestock grazing, and those with
intense livestock grazing pressures. The chemical composition of plants contributing to the bharal diet was analysed. The
bharal diet was quantified through signs of feeding on vegetation at feeding locations. Population structures of bharal populations
were recorded using a total count method. Graminoid availability was highest in areas without livestock grazing, followed
by areas with moderate and intense livestock grazing. The bharal diet was dominated by graminoids (73%) in areas with highest
graminoid availability. Graminoid contribution to the bharal diet declined monotonically (50, 36%) with a decline in graminoid
availability. Bharal young to female ratio was 3 times higher in areas with high graminoid availability than areas with low
graminoid availability. The composition of the bharal winter diet was governed predominantly by the availability of graminoids
in the rangelands. Our results suggest that bharal include more browse in their diet during winter due to competition from
livestock for graminoids. Since livestock grazing reduces graminoid availability, creation of livestock-free areas is necessary
for the conservation of grazing species such as the bharal and its predators including the endangered snow leopard in the
Trans-Himalaya. 相似文献
168.
A simplified mathematical model has been developed for understanding the combined effects of surface roughness and couple stresses on lubrication aspects of synovial joints. The modified Reynolds equation which incorporates the elastic as well as randomized surface roughness structure of cartilage with couple-stress fluid as lubricant is derived. The mean pressure, load carrying capacity and time of approach as functions of film thickness during normal articulation of joints are obtained by using Christensen stochastic theory with the assumption that the roughness asperity heights are to be small compared to the film thickness. The effects of surface roughness and elasticity are considerably pronounced for the poroelastic bearings with couple-stress fluid as lubricant compared with classical case. 相似文献
169.
Sharma RK Tuli P Makkar SS 《Plastic and reconstructive surgery》2007,119(7):2330; author reply 2330-2330; author reply 2331
170.