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991.
Sk. Sarif Hassan Pabitra Pal Choudhury Amita Pal R. L. Brahmachary Arunava Goswami 《Journal of biosciences》2010,35(3):389-393
Ligands for only two human olfactory receptors are known. One of them, OR1D2, binds to Bourgeonal, a volatile chemical constituent
of the fragrance of the mythical flower, Lily of the valley or Our Lady’s tears, Convallaria majalis (also the national flower of Finland). OR1D2, OR1D4 and OR1D5 are three full-length olfactory receptors present in an olfactory
locus in the human genome. These receptors are more than 80% identical in DNA sequences and have 108 base pair mismatches
among them. Apparently, these mismatch positions show no striking pattern using computer pattern recognition tools. In an
attempt to find a mathematical rule in those mismatches, we find that an L-system generated sequence can be inserted into
the OR1D2 subfamily-specific star model and novel full-length olfactory receptors can be generated. This remarkable mathematical
principle could be utilized for making new subfamily olfactory receptor members from any olfactory receptor subfamily. The
aroma and electronic nose industry might utilize this rule in future. 相似文献
992.
993.
Qazi A Pal J Maitah M Fulciniti M Pelluru D Nanjappa P Lee S Batchu RB Prasad M Bryant CS Rajput S Gryaznov S Beer DG Weaver DW Munshi NC Goyal RK Shammas MA 《Translational oncology》2010,3(6):389-399
INTRODUCTION: The incidence of Barrett esophageal adenocarcinoma (BEAC) has been increasing at an alarming rate in western countries. In this study, we have evaluated the therapeutic potential of sulforaphane (SFN), an antioxidant derived from broccoli, in BEAC. METHODS: BEAC cells were treated with SFN, alone or in combination with chemotherapeutic, paclitaxel, or telomerase-inhibiting agents (MST-312, GRN163L), and live cell number determined at various time points. The effect on drug resistance/chemosensitivity was evaluated by rhodamine efflux assay. Apoptosis was detected by annexin V labeling and Western blot analysis of poly(ADP-ribose) polymerase cleavage. Effects on genes implicated in cell cycle and apoptosis were determined by Western blot analyses. To evaluate the efficacy in vivo, BEAC cells were injected subcutaneously in severe combined immunodeficient mice, and after the appearance of palpable tumors, mice were treated with SFN. RESULTS: SFN induced both time- and dose-dependent decline in cell survival, cell cycle arrest, and apoptosis. The treatment with SFN also suppressed the expression of multidrug resistance protein, reduced drug efflux, and increased anticancer activity of other antiproliferative agents including paclitaxel. A significant reduction in tumor volume was also observed by SFN in a subcutaneous tumor model of BEAC. Anticancer activity could be attributed to the induction of caspase 8 and p21 and down-regulation of hsp90, a molecular chaperon required for activity of several proliferation-associated proteins. CONCLUSIONS: These data indicate that a natural product with antioxidant properties from broccoli has great potential to be used in chemoprevention and treatment of BEAC. 相似文献
994.
Ammonium supply rate influences archaeal and bacterial ammonia oxidizers in a wetland soil vertical profile 总被引:3,自引:0,他引:3
Höfferle Š Nicol GW Pal L Hacin J Prosser JI Mandić-Mulec I 《FEMS microbiology ecology》2010,74(2):302-315
Oxidation of ammonia, the first step in nitrification, is carried out in soil by bacterial and archaeal ammonia oxidizers and recent studies suggest possible selection for the latter in low-ammonium environments. In this study, we investigated the selection of ammonia-oxidizing archaea and bacteria in wetland soil vertical profiles at two sites differing in terms of the ammonium supply rate, but not significantly in terms of the groundwater level. One site received ammonium through decomposition of organic matter, while the second, polluted site received a greater supply, through constant leakage of an underground septic tank. Soil nitrification potential was significantly greater at the polluted site. Quantification of amoA genes demonstrated greater abundance of bacterial than archaeal amoA genes throughout the soil profile at the polluted site, whereas bacterial amoA genes at the unpolluted site were below the detection limit. At both sites, archaeal, but not the bacterial community structure was clearly stratified with depth, with regard to the soil redox potential imposed by groundwater level. However, depth-related changes in the archaeal community structure may also be associated with physiological functions other than ammonia oxidation. 相似文献
995.
Davinder Pal Singh Fiona F. Filardo Richard Storey Angelica M. Jermakow Shinjiro Yamaguchi Stephen M. Swain 《Physiologia plantarum》2010,138(1):74-90
We have examined the role of gibberellins (GAs) in plant development by expression of the pea GA 2-oxidase2 ( PsGA2ox2 ) cDNA, which encodes a GA inactivating enzyme, under the control of the MEDEA (MEA) promoter. Expression of MEA:PsGA2ox2 in Arabidopsis caused seed abortion, demonstrating that active GAs in the endosperm are essential for normal seed development. MEA:PsGA2ox2 plants had reduced ovule number per ovary and exhibited defects in phyllotaxy and leaf morphology which were partly suppressed by GA treatment. The leaf architecture and phyllotaxy defects of MEA:PsGA2ox2 plants were also restored by sly1-d which reduces DELLA protein stability to increase GA response. MEA:PsGA2ox2 seedlings had increased expression of the KNOTTED1 -like homeobox (KNOX) genes, BP , KNAT2 and KNAT6 , which are known to control plant architecture. The expression of KNOX genes is also altered in wild-type plants treated with GA. These results support the conclusion that GAs can suppress the effects of elevated KNOX gene expression, and raise the possibility that localized changes in GA levels caused by PsGA2ox2 alter the expression of KNOX genes to modify plant architecture. 相似文献
996.
Rakhi Pal Chaitanya Gopinath Nagesh M Rao Poulomi Banerjee Venkatesh Krishnamoorthy Neelam K. Venkataramana Satish Totey 《Cytotherapy》2010,12(6):792-806
Background aimsSpinal cord injury (SCI) is a medically untreatable condition for which stem cells have created hope. Pre-clinical and clinical studies have established that these cells are safe for transplantation. The dose dependency, survivability, route of administration, cell migration to injury site and effect on sensory and motor behavior in an SCI-induced paraplegic model were studied.MethodsA spinal cord contusion injury model was established in rats. Bone marrow (BM) mesenchymal stromal cells (MSC) were tagged to facilitate tracing in vivo. Two different doses (2 and 5 million cells/kg body weight) and two different routes of infusion (site of injury and lumbar puncture) were tested during and after the spinal shock period. The animals were tested post-transplantation for locomotor capacity, motor control, sensory reflex, posture and body position. Stem cell migration was observed 1 month post-transplantation in spinal cord sections.ResultsThe overall results demonstrated that transplantation of BM MSC significantly improved the locomotor and sensory behavior score in the experimental group compared with the sham control group, and these results were dose dependent. All the infused stem cells could be visualized at the site of injury and none was visualized at the injected site. This indicated that the cells had survived in vivo, were probably chemoattracted and had migrated to the lesion site.ConclusionsMSC transplanted with a lumbar puncture method migrate to the site of injury and are the most suitable for SCI healing. These cells demonstrate a dose-dependent effect and promote functional recovery when injected during or after the spinal shock period. 相似文献
997.
Human granulocyte–macrophage colony-stimulating factor (hGM-CSF) is a therapeutically important cytokine that is poorly expressed
because of its toxic effects on the host cells. Extracellular expression of hGM-CSF was obtained by cloning its gene in Pichia pastoris under the constitutive glyceraldehyde-3-phosphate dehydrogenase (GAP) promoter with an N-terminal α peptide sequence for
its extracellular production. The clones obtained were screened for a hyper producer following which media and cultivation
conditions were optimized in shake flasks. Batch and fed-batch studies were performed in a bioreactor where different feed
compositions were fed exponentially to obtain high biomass concentrations. Feeding of complex media allowed us to maintain
a high specific growth rate of 0.2 h−1 for the longest time period, and a final biomass of 98 g DCW/l was obtained in 34 h. Product formation was found to be growth
associated, and the product yield with respect to biomass (Y
P/X) was ∼2.5 mg/g DCW. The above fed-batch strategy allowed us to obtain fairly pure glycosylated hGM-CSF at a final product
concentration of 250 mg/l in the culture supernatant with a high volumetric productivity of 7.35 mg l−1 h−1. 相似文献
998.
Pal P Xi H Kaushal R Sun G Jin CH Jin L Suarez BK Catalona WJ Deka R 《Human genetics》2006,120(2):187-192
There is considerable evidence that genetic factors are involved in prostate cancer susceptibility. We have studied the association of 11 single nucleotide polymorphisms (SNPs) in the HEPSIN gene (HPN) with prostate cancer in men of European ancestry. HPN is a likely candidate in prostate cancer susceptibility, as it encodes a transmembrane cell surface serum protease, which is overexpressed in prostate cancer; HPN is also located on 19q11–q13.2, where linkage is found with prostate cancer susceptibility. In this case-control association study (590 men with histologically verified prostate cancer and 576 unrelated controls, all of European descent), we find significant allele frequency differences between cases and controls at five SNPs that are located contiguously within the gene. A major 11-locus haplotype is significantly associated, which provides further support that HPN is a potentially important candidate gene involved in prostate cancer susceptibility. Association of one of the SNPs with Gleason score is also suggestive of a plausible role of HPN in tumor aggressiveness. 相似文献
999.
Gupta A Kumar R Pal K Singh V Banerjee PK Sawhney RC 《Molecular and cellular biochemistry》2006,290(1-2):193-198
The present investigation was undertaken to determine the efficacy of topical administration of flavone of sea buckthorn (Hippophae rhamnoides L.) on cutaneous wound healing in rats. Four full-thickness excision wounds were created on the back of rat and 1.0% w/v
flavone prepared in propylene glycol was applied topically. Control animals received the vehicle alone in an identical manner.
The healing of the wound was assessed by the rate of wound contraction, period of epithelialization, hydroxyproline, hexosamine,
antioxidants estimation and histopathology of the granulation tissue. The sea buckthorn flavone promoted the wound healing
activity as indicated by improved rate of wound contraction, decreased time taken for epithelialization (16.3 days versus
24.8 days in controls) and significant increase in hydroxyproline (26.0%) and hexosamine (30.0%) content. These findings were
also confirmed by histopathological examinations. In addition, it was observed that sea buckthorn flavone possesses potent
antioxidant properties as evidenced by significant increase in reduced glutathione (55.0%), vitamin C (70.0%) and catalase
(20.0%) activities in wound granulation tissue. The flavone treatment also resulted in significant decrease in lipid peroxide
levels (39.0%). The results suggest that the sea buckthorn flavone promotes wound healing activity. 相似文献
1000.