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951.
952.
A study was undertaken to investigate the presence of archaeal diversity in saltpan sediments of Goa, India by 16S rDNA-dependent
molecular phylogeny. Small subunit rRNA (16S rDNA) from saltpan sediment metagenome were amplified by polymerase chain reaction
(PCR) using primers specific to the domain archaea. 10 unique phylotypes were obtained by PCR based RFLP of 16S rRNA genes
using endonuclease Msp 1, which was most suitable to score the genetic diversity. These phylotypes spanned a wide range within the domain archaea
including both crenarchaeota and euryarcheaota. None of the retrieved crenarchaeota sequences could be grouped with previously
cultured crenarchaeota however; two sequences were related with haloarchaea. Most of the sequences determined were closely
related to the sequences that had been previously obtained from metagenome of a variety of marine environments. The phylogenetic
study of a site investigated for the first time revealed the presence of low archaeal population but showed yet unclassified
species, may specially adapted to the salt pan sediment of Goa. 相似文献
953.
Isolation, structural characterization and antioxidant activity of a new water-soluble polysaccharide from Acanthophyllum bracteatum roots 总被引:1,自引:0,他引:1
Jahanbin K Gohari AR Moini S Emam-Djomeh Z Masi P 《International journal of biological macromolecules》2011,49(4):567-572
ABPS-1, a new water-soluble polysaccharide with molecular weight of 26 kDa and a specific optical rotation of +170° (c 1.0, H2O), was extracted from the roots of Acanthophyllum bracteatum by warm water and further successively purified through DEAE-cellulose A52 and Sephadex G-100 columns. Monosaccharide analysis revealed that the ABPS-1 was composed of Glc, Gal and Ara with a relative molar ratio of 1.4:5.2:1.0. Its structural features were elucidated by a combination of FT-IR, methylation and GC-MS analysis, periodate oxidation and Smith degradation, partial acid hydrolysis and 13C and 1H NMR spectroscopy. The data obtained indicate that ABPS-1 possessed a backbone of α-(1 → 6)-linked Gal with branches attached to O-2 by α-1 → linked Glc and at O-3 by α-1 → linked Gal and by α-(1 → 3)-linked Ara. The in vitro antioxidant activity showed that ABPS-1 possesses DPPH radical-scavenging activity in a concentration-dependent manner with an EC50 value of 2.6 mg/ml. 相似文献
954.
Thermal adaptability and disease association in common carp (Cyprinus carpio communis) acclimated to different (four) temperatures 总被引:1,自引:0,他引:1
The present study was designed to investigate the effect of temperature (20 °C, 24 °C, 28 °C and 32 °C) on the heamato-biochemical and histological alterations of Cyprinus carpio communis. Increase in the temperature showed significant decrease in the serum protein, while a reduced level of blood glucose at high temperature of 32 °C was observed leading to hypoglycemic conditions in the experimental fishes. A significant correlation (P<0.01) was observed between cholesterol (Cho) and triglycerides (TG) for different temperature treatments. Elevated blood urea nitrogen (BUN) at high temperatures was a good indicator of gill osmoregulatory failure. A variation of 86.40% and 38.33%, respectively, was noticed in alanine aminotransferase (ALT) and aspartate aminotransferase (AST) at 32 °C over minimum experimental temperature of 20 °C. The increase in red blood cell (RBC) and Heamoglobin (Hb) concentration is associated with the decrease of mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC), could be the reason for observed poikilo-anisocytosis. Histological studies of different organs of experimental fishes showed accumulation of MMC's (melanomacrophagic centers) and atrophy of the interrenal tissue on exposure to various levels of temperature. These changes were related to severity of thermal stress, being most marked when high temperature was prolonged during acclimatization. Some fishes were found infested by protozoan parasite at elevated temperature of 32 °C. Increased levels of certain biochemical and haemotological parameters studied were strongly correlated with disease in the Cyprinus carpio communis species. 相似文献
955.
Farooqi AA Bhatti S Nawaz A Khalid AM 《The International journal of biological markers》2011,26(2):75-81
The touchstone to evaluate accurately the aggressiveness and invasiveness of prostate cancer is something of a holy grail in the facet of urologic oncology. Gene expression and sequencing studies have improved our interpretations of the genetic determinants of the disease but are unsuccessful in the establishment of any unified classification to improve the molecular stratification. These questions addressing failure in rational drug design are difficult to answer in the multifaceted and heterogeneous pathogenesis of prostate cancer. In this review, we have developed a roadmap of the "recalcitrant prostate cancer proteome" to recognize the aspects of prostate cancer that may be helpful in effectively translating these findings to the clinic. 相似文献
956.
Ahmad MS Ashraf M Tabassam Q Hussain M Firdous H 《Biological trace element research》2011,144(1-3):1229-1239
The phytotoxic effects of lead (Pb) on seed germinability, seedling growth, photosynthetic performance, and nutrient accumulation (K(+) and Cu(2+)) in two maize genotypes (EV-1098 and EV-77) treated with varying levels of PbSO(4) (0.01, 0.1, and 1.0 mg L(-1)) were appraised in this study. In the seed germination experiment, lead stress significantly reduced seed germination percentage and index, plumule and radicle lengths as well as fresh and dry weights in both genotypes. In the second experiment, lengths and fresh and dry weights of shoots and roots decreased due to Pb in both genotypes with increase in plant age. Higher Pb levels also decreased photosynthetic rate (A), water use efficiency (A/E), and intrinsic water use efficiency (A/g(s)), but increased transpiration rate (E) and C(i)/C(a) ratio as a result of increase in stomatal conductance (g(s)). The concentrations of K(+) and Cu(2+) decreased in root, stem, and leaves of both genotypes, which could be a direct consequence of multifold increase in Pb concentration in these tissues. Overall, cv. EV-1098 had better Pb tolerance potential than EV-77 because the former genotype showed less reduction in seed germinability parameters, photosynthetic performance, and K(+) and Cu(2+) accumulation in shoot and root under lead stress. 相似文献
957.
Kabir ME Krishnaswamy S Miyamoto M Furuichi Y Komiyama T 《Applied microbiology and biotechnology》2011,90(2):553-564
Phage-display and competitive panning elution leads to the identification of minimum-sized antigen binders together with conventional
antibodies from a mouse cDNA library constructed from HM-1 killer toxin neutralizing monoclonal antibody (nmAb-KT). Antigen-specific
altered camelid-like single-domain heavy chain antibody (scFv K2) and a conventional antibody (scFv K1) have been isolated
against the idiotypic antigen nmAb-KT. The objectives of the study were to examine (1) their properties as compared to conventional
antibodies and also (2) their antifungal activity against different pathogenic and non-pathogenic fungal species. The alternative
small antigen-binder, i.e., the single-domain heavy chain antibody, was originated from a conventional mouse scFv phage library
through somatic hyper-mutation while selection against antigen. This single-domain antibody fragment was well expressed in
bacteria and specifically bound with the idiotypic antigen nmAb-KT and had a high stability and solubility. Experimental data
showed that the binding affinity for this single-domain antibody was 272-fold higher (K
d = 1.07 × 10−10 M) and antifungal activity was three- to fivefold more efficient (IC50 = 0.46 × 10−6 to 1.17 × 10−6 M) than that for the conventional antibody (K
d = 2.91 × 10−8 M and IC50 = 2.14 × 10−6 to 3.78 × 10−6 M). The derived single-domain antibody might be an ideal scaffold for anti-idiotypic antibody therapy and the development
of smaller peptides or peptide mimetic drugs due to their less complex antigen-binding site. We expect that such single-domain
synthetic antibodies will find their way into a number of biotechnological or medical applications. 相似文献
958.
Toxic Effect of Nickel (Ni) on Growth and Metabolism in Germinating Seeds of Sunflower (<Emphasis Type="Italic">Helianthus annuus</Emphasis> L.) 总被引:1,自引:0,他引:1
Ashraf MY Sadiq R Hussain M Ashraf M Ahmad MS 《Biological trace element research》2011,143(3):1695-1703
To assess the toxic effect of nickel (Ni) on the growth and some key metabolic processes in sunflower, varying levels of Ni
as Ni(NO3)2 up to 60 mg L−1 were applied once to sunflower cultivars SF-187 and Hysun-33 at sowing time in sand culture. An increase in Ni in the growth
medium adversely affected growth parameters, sugar concentration (both reducing and non-reducing), as well as the activities
of α-amylase and protease. It also slowed down mobilization of stored proteins and amino acids in the germinating seeds. However,
an increase in the activities of α-amylase and protease was observed over time from 24 to 120 h after sowing. Cultivar Hysun-33
showed better performance than SF-187 in the presence of excess Ni. Overall, Ni-induced reduction in germination of sunflower
seed appeared to be due to disturbance in biochemical metabolism as the availability of sugars for the synthesis of metabolic
energy as well as necessary amino acids for the synthesis of proteins and enzymes essential for the growing embryo are generally
reduced due to suppression in α-amylase and protease activities. 相似文献
959.
In the present study, the newly synthesized TRH analog (l-pGlu-(2-propyl)-l-His-l-ProNH2; NP-647) was evaluated for its effects in in vitro (oxygen glucose deprivation (OGD)-, glutamate- and H2O2-induced injury in PC-12 cells) and in vivo (transient global ischemia) models of cerebral ischemic injury. PC-12 cells were subjected to oxygen and glucose deprivation for 6 h. Exposure of NP-647 was given before and during OGD. In glutamate and H2O2 induced injury, exposure of NP-647 was given 1, 6 and 24 h prior to exposure of glutamate and H2O2 exposure. NP-647, per se found to be non-toxic in 1-100 μM concentrations. NP-647 showed protection against OGD at the 1 and 10 μM. The concentration-dependent protection was observed in H2O2- and glutamate-induced cellular injury. In in vivo studies, NP-647 treatment showed protection of hippocampal (CA1) neuronal damage in transient global ischemia in mice and subsequent improvement in memory retention was observed using passive avoidance retention test. Moreover, administration of NP-647 resulted in decrease in inflammatory cytokines TNF-α and IL-6 as well as lipid peroxidation. These results suggest potential of NP-647 in the treatment of cerebral ischemia and its neuroprotective effect may be attributed to reduction of excitotoxicity, oxidative stress and inflammation. 相似文献
960.
Karabasil MR Hasegawa T Azlina A Purwanti N Yao C Akamatsu T Tomioka S Hosoi K 《Biology of the cell / under the auspices of the European Cell Biology Organization》2011,103(2):69-86
Background information. AQPs (aquaporins) are water channel proteins that are expressed in almost all living things. In mammalians, 13 members of AQPs (AQP0–12) have been identified so far. AQP5 is known to be expressed mostly in the exocrine cells, including the salivary gland acinar cells. A naturally occurring point mutation (G308A, Gly103 > Asp103) was earlier found in the rat AQP5 gene [Murdiastuti, Purwanti, Karabasil, Li, Yao, Akamatsu, Kanamori and Hosoi (2006) Am. J. Physiol. 291 , G1081–G1088]; in this mutant, the rate of initial saliva secretion under stimulated and unstimulated conditions is less than that for the wt (wild‐type) animals. Results. Here the mutant molecule was characterized in detail. Using the Xenopus oocyte system, we demonstrated the mutant AQP5 to have water permeability almost the same as that of the wt molecule. Mutant and wt AQP5s, tagged with GFP (green fluorescent protein; GFP‐AQP5s) and expressed in polarized MDCK‐II (Madin—Darby canine kidney II) cells, first appeared in the vesicular structure(s) in the cytoplasm, and were translocated to the upper plasma membrane or apical membrane during cultivation, with the mutant GFP‐AQP5 being translocated less efficiently. Thapsigargin and H‐89 both induced translocation in vitro of either molecule, whereas colchicine inhibited this activity; the fraction of cells showing apical localization of mutant GFP‐AQP5 was less than that showing that of the wt molecule under any of the experimental conditions used. In the mutant SMG (submandibular gland) tissue, localization of AQP5 in the apical membrane of acinar cells was extremely reduced. Vesicular structures positive for AQP5 and present in the cytoplasm of the acinar cells were co‐localized with LAMP2 (lysosome‐associated membrane protein 2) or cathepsin D in the mutant gland, whereas such co‐localizations were very rare in the wt gland, suggesting that the mutant molecules largely entered lysosomes for degradation. Conclusion. Replacement of highly conserved hydrophobic Gly103 with strongly hydrophilic Asp103 in rat AQP5, though it did not affect water permeability, may possibly have resulted in less efficient membrane trafficking and increased lysosomal degradation, leading to its lower expression in the apical membrane of the acinar cells in the SMG. 相似文献