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161.
Molecular Biology Reports - On the background of the epidemiological link between diabetes and oral cancer, the present study aimed to analyze the potential involvement of selected glucose...  相似文献   
162.
The vacuolar Na+/H+ antiporter is known to alleviate saline stress by sequestering Na+ in both wild-type Arabidopsis and rice and when over-expressed in many transgenic plants. Here we report on the effect of the NHX1 transgene on the salt tolerance properties it confers to a rice landrace and a commercial cultivar suitable for the dry winter season, but which suffers loss due to seasonal stresses, particularly in the coastal areas. The Nipponbare Na+/H+ antiporter 1.9 kb cDNA was cloned into pCAMBIA1305.1 under the control of the CaMV35S promoter and transformed into tissue-culture-responsive rice landrace Binnatoa (BA). The best-expressing transgenic line at T2 was found to be significantly tolerant at the seedling stage and was advanced to T3. The transgene was then transferred to the tissue-culture recalcitrant farmer-popular commercial rice genotype, BRRIdhan 28 (BR28) by crossing. The data generated both from semi-quantitative RT-PCR and western blot hybridization revealed that the transgene showed similar expression in the crossbred BR28 plants and BA transgenic line. Comparative stress tolerance tests, however, revealed that the BR28 crossbred lines were significantly less tolerant than its transgenic parent BA at both seedling and reproductive stages. A single successful transgenic event may therefore not show the same performance in the recipient genetic background, if introgressed by crossing.  相似文献   
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164.
Glial Fibrillary Acidic Protein (GFAP) is an intermediate-filament (IF) protein that maintains the astrocytes of the Central Nervous System in Human. This is differentially expressed during serological studies in inflamed condition such as Rheumatoid Arthritis (RA). Therefore, it is of interest to glean molecular insight using a model of GFAP (49.88 kDa) due to its crystallographic nonavailability. The present study has been taken into consideration to construct computational protein model using Modeller 9.11. The structural relevance of the protein was verified using Gromacs 4.5 followed by validation through PROCHECK, Verify 3D, WHAT-IF, ERRAT and PROVE for reliability. The constructed three dimensional (3D) model of GFAP protein had been scrutinized to reveal the associated functions by identifying ligand binding sites and active sites. Molecular level interaction study revealed five possible surface cavities as active sites. The model finds application in further computational analysis towards drug discovery in order to minimize the effect of inflammation.  相似文献   
165.
A partial nitrification system was investigated for 471 days under DO varying concentrations for assessing its stability and population dynamics. Within 130 days of operation at feed DO concentration of 1.0 ± 0.1 mg/L, more than 85% of nitrite was accumulated. Efficiency deteriorated when the feed DO concentration was increased to 4.2 ± 0.3 mg/L. Nitrite accumulation could not be re-established on decreasing feed DO to 1.0 ± 0.1 mg/L. Even at DO concentration of <0.05 mg/L, nitrate production was observed; a condition termed as anoxic nitrification. NOB was detected in the biomass even under this condition by Fluorescence in-situ hybridization (FISH) analysis. Through 16S rRNA gene sequencing a major fraction of unknown bacterial sequences closely resembling haloalkalophilic bacteria of marine origin were detected. The study indicated that these bacterial species might play a role in anoxic nitrification and that NOB could survive extreme low DO condition.  相似文献   
166.
Sharma S  Biswas S 《Bioinformation》2011,6(9):364-365
The last decade was taken by storm when the existence of a class of small (˜22nt long) non ― coding RNA species, known as microRNAs (miRNAs) came into light. MicroRNAs are one of the most abundant groups of regulatory genes in multicellular organisms and play fundamental roles in many cellular processes. Among these, miRNAs have been shown to prevent cell division and drive terminal differentiation, thus playing a causal role in the generation or maintenance of cancerous tumours. The unique expression profiles of different miRNAs in various types and stages of cancer suggest their performance as novel biomarkers. This discussion focuses on miRNAs implicated in cancer-associated events and strives to re-establish their sequential features which may classify them to be oncogenic.  相似文献   
167.
Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease of unidentified aetiology, chiefly affecting the synovial membranes of joints, cartilage, bone, bursa and tendon sheath. Osteoarthritis (OA) is a degenerative disorder and encompass different sets of pathogenic pathways than RA; however, it shows a medley of clinical manifestations or symptoms resembling RA. Hence, we intend to identify more disease specific biomarkers through the meta-analysis of microarray datasets that can be crucial in the differential diagnosis, disease specific treatment as well as management of both RA and OA in a typical clinical setting.  相似文献   
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169.
Forty nine Campylobacter jejuni isolates from cattle feces collected from Alberta feedlots and 50 clinical C. jejuni isolates from people in Alberta were tested for the presence of 14 genes encoding putative virulence factors by PCR. These included genes implicated in adherence and colonization (flaC, cadF, docC, racR, jlpA, peb1, and dnaJ), invasion (virB11, ciaB, pldA, and iamA) and protection against harsh conditions (htrA, cbrA, and sodB). The genes examined were widely distributed in both the cattle fecal isolates and the human isolates. Of the isolates tested, 67% contained all of the genes except virB11. The cadF gene was found in 100% of the isolates tested. The presence or absence of virulence-associated genes was not associated with the ability of the organism to colonize birds. All of the C. jejuni isolates used to challenge birds were able to colonize the animals regardless of virulence gene profile. While some diversity in the profile of the occurrence of virulence-associated genes in C. jejuni exists, the distribution of these putative virulence-associated genes isolates from feedlot cattle feces and humans in Alberta was similar. In addition it was not possible to predict the ability of the selected isolates to colonize young chicks based on the presence of these genes coding for virulence determinants.  相似文献   
170.
Neisseria gonorrhoeae, a sexually-transmitted gram-negative bacterium, causes gonorrhoea in humans. The min genes of N. gonorrhoeae are involved in cell division site selection with oxyR co-transcribed with these genes. The mutation in min genes and oxy R cause aberrant cell morphology and aggregation patterns, respectively. Our objective was to assess the contribution of neisserial min operon cell division genes i.e. minC, minD and oxyR in virulence. Compared to the N. gonorrhoeae parental strain (Ng CH811Str(R)), its isogenic mutants with insertionally inactivated minC (Ng CSRC1), minD (Ng CJSD1) or oxyR (Ng KB1) showed reduced adherence to and invasion of urethral epithelial cells. This may be explained by defective microcolony formation in the mutant strains, possibly owing to abnormal morphology and aggregation. The expression levels of surface virulence factors like Opa, pilin and lipooligosaccharide in the mutants were unchanged relative to Ng CH811Str(R). Furthermore, in urethral epithelial cells, the min and oxyR mutants induced the release of proinflammatory cytokines like IL6 and IL8 to levels similar to that induced by the parental strain. Taken together, our studies indicate that inactivation of minC, minD or oxyR in N. gonorrhoeae attenuates its ability to bind to and invade urethral epithelial cells without altering its potential to induce IL6 and IL8 release.  相似文献   
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