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81.
A set of 104 wheat recombinant inbred lines (RILs) obtained from a cross between parents resistant (HD 29) and susceptible (WH 542) to karnal bunt (KB) (caused by Neovossia indica) were screened and used to identify random amplified polymorphic DNA (RAPD) markers linked with resistance to karnal bunt as these would allow indirect marker assisted selection of KB resistant genotypes. The two parents were analysed with 92 RAPD primers. A total of 65 primers proved functional by giving scorable polymerase chain reaction (PCR) products. Of these, 21 (32 %) primers detected polymorphism between the two parental genotypes. Using these primers, bulked segregant analysis was carried out on two bulk DNAs, one obtained by pooling DNA from 10 KB resistant RILs and the other similarly derived by pooling 10 KB susceptible RILs. One marker, OPM-20 showed apparent association with resistance to KB. This was confirmed following selective genotyping of individual RILs included in the bulks.  相似文献   
82.
BackgroundAcuros XB (AXB) may predict better rectal toxicities and treatment outcomes in cervix carcinoma. The aim of the study was to quantify the potential impact of AXB computations on the cervix radiotherapy using the RapidArc (RA ) technique as compared to anisotropic analytical algorithm (AA) computations.Materials and methodsA cohort of 30 patients previously cared for cervix carcinoma (stages II–IIIB) was selected for the present analysis. The RA plans were computed using AA and AXB dose computation engines under identical beam setup and MLC pattern.ResultsThere was no significant (p > 0.05) difference in D95% and D98% to the planning target volume (PTV); moreover, a significant (p < 0.05) rise was noticed for mean dose to the PTV (0.26%), D50% (0.26%), D2% (0.80%) and V110% (44.24%) for AXB computation as compared to AA computations. Further, AXB estimated a significantly (p < 0.05) lower value for maximum and minimum dose to the PTV. Additionally, there was a significant (p < 0.05) reduction observed in mean dose to organs at risk (OARs) for AXB computation as compared to AA, though the reduction in mean dose was non-significant (p > 0.05) for the rectum. The maximum difference observed was 4.78% for the rectum V50Gy, 1.72%, 1.15% in mean dose and 2.22%, 1.48% in D2% of the left femur and right femur, respectively, between AA and AXB dose estimations.ConclusionFor similar target coverage, there were significant differences observed between the AAA and AXB computations. AA underestimates the V50Gy of the rectum and overestimates the mean dose and D2% for femoral heads as compared to AXB. Therefore, the use of AXB in the case of cervix carcinoma may predict better rectal toxicities and treatment outcomes in cervix carcinoma using the RA technique.  相似文献   
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The most frequently reported symptom of exposure to high altitude is loss of body mass and decreased performance which has been attributed to altered protein metabolism affecting skeletal muscles mass. The present study explores the mechanism of chronic hypobaric hypoxia mediated skeletal muscle wasting by evaluating changes in protein turnover and various proteolytic pathways. Male Sprague-Dawley rats weighing about 200 g were exposed to hypobaric hypoxia (7,620 m) for different durations of exposure. Physical performance of rats was measured by treadmill running experiments. Protein synthesis, protein degradation rates were determined by (14)C-Leucine incorporation and tyrosine release, respectively. Chymotrypsin-like enzyme activity of the ubiquitin-proteasome pathway and calpains were studied fluorimetrically as well as using western blots. Declined physical performance by more than 20%, in terms of time taken in exhaustion on treadmill, following chronic hypobaric hypoxia was observed. Compared to 1.5-fold increase in protein synthesis, the increase in protein degradation was much higher (five-folds), which consequently resulted in skeletal muscle mass loss. Myofibrillar protein level declined from 46.79 ± 1.49 mg/g tissue at sea level to 37.36 ± 1.153 (P < 0.05) at high altitude. However, the reduction in sarcoplasmic proteins was less as compared to myofibrillar protein. Upregulation of Ub-proteasome pathway (five-fold over control) and calpains (three-fold) has been found to be important factors for the enhanced protein degradation rate. The study provided strong evidences suggesting that elevated protein turnover rate lead to skeletal muscle atrophy under chronic hypobaric hypoxia via ubiquitin-proteasome pathway and calpains.  相似文献   
85.
Chaudhary AA  Hemant  Mohsin M  Ahmad A 《Protoplasma》2012,249(2):417-422
In this study, loop-mediated isothermal amplification (LAMP)-based molecular marker was developed for authentication of Catharanthus roseus, a medicinal plant. Samples of this plant were collected from different geographical locations in India. Random amplified polymorphic deoxyribonucleic acid (DNA) analysis of collected samples was carried out with 25 random primers. A 610-bp DNA fragment, common to all accessions, was eluted, cloned, and sequenced. Four LAMP primers were designed on the basis of sequence of 610 bp DNA fragment. LAMP reaction, containing 10× Bst DNA polymerase reaction buffer, Bst DNA polymerase, four in-house designed primers, dNTPs, MgSO4, and betaine, was incubated at 65°C for 1 h. The resulting amplicon was visualized by adding SYBR Green I to the reaction tube. The data showed confirmatory results. Since the assay method is simple, sensitive, and cost-effective, it is a feasible method for identifying and authentication of C. roseus.  相似文献   
86.
Multicopper oxidase (MCO) is an enzyme which involves in reducing the oxygen in a four electron reduction to water with concomitant one electron oxidation of reducing the substrate. We have generated the 3-D structure of MCO by homology modeling and validated on the basis of free energy while 90.4 % amino acid residues present in allowed regions of Ramachandran plot. The screening of potential hazardous aromatic compounds for MCO was performed using molecular docking. We obtained Sulfonaphthal, Thymolphthalein, Bromocresol green and Phloretin derivatives of phenol and aromatic hydrocarbon were efficient substrates for MCO. The phylogeny of MCO reveals that other bacteria restrain the homologous gene of MCO may play an important role in biodegradation of aromatic compounds. We have demonstrated the gene regulatory network of MCO with other cellular proteins which play a key role in gene regulation. These findings provide a new insight for oxidization of phenolic and aromatic compounds using biodegradation process for controlling environmental pollution.  相似文献   
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88.
A non-tissue culture approach for the generation of transgenic Indian mustard (Brassica juncea) plants using Agrobacterium tumefaciens was developed. Inflorescences with floral buds were vacuum infiltrated with a suspension of A. tumefaciens strain EHA105 carrying a binary vector with an intron-containing β-glucuronidase (GUS) gene (uidA) as a scorable marker and a neomycin phosphotransferase gene (nptII) as a selectable marker. The seeds of agro-infiltrated plants (T0) were germinated on a medium containing 130 mg l−1 kanamycin, and the seedlings that remained green were considered T1 transgenic plants. Histochemical GUS assays, PCR, Southern analysis, and RT-PCR confirmed that both transgenes were integrated into the genome of T1 plants and were stably transmitted and expressed for over three generations. The transformants were obtained within 3–4 mo at a transformation frequency of 0.8%. This method may facilitate functional genomics and improvement of Brassica with novel desirable traits and with less time and expense.  相似文献   
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90.
Species of the monogenean genus Thaparocleidus are specific to freshwater siluriform fish. The infection caused by these gill parasites are a major health problem to fish. But, to focus the control strategies of these parasites, first it is important to establish an accurate discrimination by molecular methods. In the present study, phylogenetic and structural analysis of 28S region of ribosomal DNA of T. wallagonius species collected from fish Wallago attu from Meerut (U.P.), India, was carried out. In the first step, we amplified, sequenced 28S region of ribosomal DNA of T. wallagonius to establish the phylogenetic relationship with other species of this genus. T. wallagonius found on gill filaments of fish W. attu, is the most primitive parasite of this genus from India, was unequivocally discriminate from other species of the same genus in this study. A secondary-structure model of the large subunit rDNA was also predicted using a combined comparative and thermodynamic approach. Molecular morphometric and phylogenetic relationship of T. wallagonius are discussed in detailed that based on molecular analysis using bioinformatic tools.  相似文献   
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