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31.
Bean common mosaic potyvirus (BCMV) is an important seed borne pathogen of French bean. Differential inoculation with bean
common mosaic virus at cotylodonary trifoliate leaf stage and pre-flowering stage of crop growth revealed that cotyledonary
leaf infection favored maximum disease expression. Under immunosorbent electron microscopy (ISEM) the virus particles of filamentous
structure having a diameter of 750 nm (l) and 15 nm (w) were observed. These particles gave positive precipitin tests with
polyclonal antiserum of Potato virus Y. 相似文献
32.
Jagesh K. Tiwari Poonam D. Sarkar SK. Pandey Jai Gopal S. Raj Kumar 《Plant Cell, Tissue and Organ Culture》2010,103(2):175-187
Interspecific potato somatic hybrids between Solanum tuberosum L. (di)haploid C-13 and 1 endosperm balance number non-tuberous wild species S. etuberosum Lindl. were produced by protoplasts electrofusion. The objective was to transfer virus resistance from this wild species
into the cultivated potatoes. Post-fusion products were cultured in VKM medium followed by regeneration of calli in MS13 K medium at 20°C under a 16-h photoperiod, and regenerants were multiplied on MS medium. Twenty-one somatic hybrids were
confirmed by RAPD, SSR and cytoplasm (chloroplast/mitochondria) type analysis possessing species-specific diagnostic bands
of corresponding parents. Tetraploid nature of these somatic hybrids was determined through flow cytometry analysis. Somatic
hybrids showed intermediate phenotypes (plant, leaves and floral morphology) to their parents in glass-house grown plants.
All the somatic hybrids were male-fertile. ELISA assay of somatic hybrids after artificial inoculation of Potato virus Y (PVY)
infection reveals high PVY resistance. 相似文献
33.
The study is aimed at exploring the utility of thermoanalytical methods in the solid-state characterization of various crystalline
forms of nevirapine. The different forms obtained by recrystallization of nevirapine from various solvents were identified
using differential scanning calorimetry and thermogravimetric analysis (TGA). The appearance of desolvation peak accompanied
by weight loss in TGA indicated the formation of solvates: hemi-ethanolate (Form I), hemi-acetonitrilate (Form II), hemi-chloroformate
(Form III), hemi-THF solvate (Form IV), mixed hemi-ethanolate hemi-hydrate (Form V), and hemi-toluenate (Form VI). The higher
desolvation temperatures of all the solvates except toluenate than their respective boiling point indicate tighter binding
of solvent. Emphasis has been laid on the determination of heat capacity and heat of solution utilizing microreaction calorimeter
to further distinguish the various forms. The enthalpy of solution (ΔH
sol), an indirect measure of the lattice energy of a solid, was well correlated with the crystallinity of all the solid forms
obtained. The magnitude of ΔH
sol was found to be −14.14 kJ/mol for Form I and −2.83 kJ/mol for Form V in phosphate buffer of pH 2, exhibiting maximum ease
of molecular release from the lattice in Form I. The heat capacity for solvation (ΔC
p) was found to be positive, providing information about the state of solvent molecules in the host lattice. The solubility
and dissolution rate of the forms were also found to be in agreement with their enthalpy of solution. Form (I), being the
most exothermic, was found to be the most soluble of all the forms. 相似文献
34.
Two drought tolerant varieties TKM-1 and TKM-2 and two drought susceptible varieties Jaya and Improved Sabarmati of rice were studied for soluble protein pattern and isoenzymes of malate dehydrogenase, glutamate dehydrogenase, esterase and peroxidase during germination at different water stress. MDH, GDH and esterase patterns were not affected, but the soluble proteins were changed. Peroxidase isoenzyme pattern from drought tolerant and susceptible varieties showed characteristic differences. The intensity of bands with higher electrophoretic mobility decreased in Jaya and Improved Sabarmati while in TKM-1 and TKM-2 the intensity of these bands did not change much after 72 hr water stress. In shoots of Jaya and Improved Sabarmati, the activity of the peroxidase isoenzymes decreased more than in TKM-1 and TKM-2 shoots with increase in water stress. 相似文献
35.
Sheetal Yadav Poonam Rana Navinder Saini Sunita Jain Rajinder K. Jain 《Journal of plant biochemistry and biotechnology.》2008,17(1):1-8
Breeding for salt tolerance using traditional screening and selection methods have been limited by the complex and polygenic nature of salt tolerance trait. This study was designed to evaluate some of the premium Basmati rice varieties for salt tolerance and to characterize genetic diversity among the rice varieties with different adaptations to saline soils using microsatellite (SSR) and ISSR markers. Plants of nine rice varieties including salt tolerant, salt sensitive and traditional Basmati, were grown in hydroponics using Yoshida solution containing 0 (control, pH 5.0) and 30 mM NaCl (Electrical conductivity 4.8 d/S, pH 5.0) and assessed for salinity tolerance on 1–9 scale as per IRRI standard evaluation system using seedling growth parameters, visual salt injuries and Na-K ratio. Physio-morphological studies showed that traditional Basmati rice varieties (Basmati 370 and HBC19) were more sensitive than the salt sensitive control variety, MI-48. SSR as well as ISSR marker systems generated higher levels of polymorphism and could distinguish between all the 9 rice cultivars. A total of 299 (225 polymorphic) and 437 (430 polymorphic) bands were detected using 28 UBC ISSR primers and 100 welldistributed mapped SSR markers, respectively. ISSR and SSR marker data-sets showed moderate levels of positive correlation (Mantel test, r = 0.43). The ISSR and SSR marker data analyzed using clustering algorithms showed two distinct clusters separating the Basmati (Basmati 370, HBC19 and CSR-30) from other non-aromatic indica (IR36, Pokkali, CSR10 and MI-48) rice varieties indicating greater divergence between Basmati and non-aromatic indica rice genotypes. Marker analysis showed a close relationship among the two traditional (Basmati 370 and HBC19) and cross-bred (CSR30) Basmati rice varieties and greater diversity between the two salt-tolerant genotypes, Pokkali and BR4-10. 相似文献
36.
Taneja P Nasheuer HP Hartmann H Grosse F Fanning E Weisshart K 《The Biochemical journal》2007,407(2):313-320
The initiation of SV40 (simian virus 40) DNA replication requires the co-operative interactions between the viral Tag (large T-antigen), RPA (replication protein A) and Pol (DNA polymerase alpha-primase) on the template DNA. Binding interfaces mapped on these enzymes and expressed as peptides competed with the mutual interactions of the native proteins. Prevention of the genuine interactions was accomplished only prior to the primer synthesis step and blocked the assembly of a productive initiation complex. Once the complex was engaged in the synthesis of an RNA primer and its extension, the interfering effects of the peptides ceased, suggesting a stable association of the replication factors during the initiation phase. Specific antibodies were still able to disrupt preformed interactions and inhibited primer synthesis and extension activities, underlining the crucial role of specific protein-protein contacts during the entire initiation process. 相似文献
37.
Gupta A Chattopadhyay I Dey S Nasipuri P Das SK Gangopadhyay PK Ray K 《Cellular and molecular neurobiology》2007,27(8):1023-1033
Aims We aim to identify the molecular defects in the ATP7B, the causal gene for Wilson disease (WD), in eastern Indian patients and attempt to assess the overall mutation spectrum
in India for detection of mutant allele for diagnostic purposes. Methods Patients from 109 unrelated families and their first-degree relatives comprising 400 individuals were enrolled in this study
as part of an ongoing project. Genomic DNA was prepared from the peripheral blood of Indian WD patients. PCR was done to amplify
the exons and flanking regions of the WD gene followed by sequencing, to identify the nucleotide variants. Results In addition to previous reports, we recently identified eight mutations including three novel (c.3412 + 1G > A, c.1771 G > A,
c.3091 A > G) variants, and identified patients with variable phenotype despite similar mutation background suggesting potential
role of modifier locus. Conclusions So far we have identified 17 mutations in eastern India including five common mutations that account for 44% of patients.
Comparative study on WD mutations between different regions of India suggests high genetic heterogeneity and the absence of
a single or a limited number of common founder mutations. Genotype–phenotype correlation revealed that no particular phenotype
could be assigned to a particular mutation and even same set of mutations in different patients showed different phenotypes. 相似文献
38.
Acrolein is a highly reactive alpha, beta-unsaturated aldehyde, and a product of lipid peroxidation reactions. Acrolein is
also an environmental pollutant and a key component of cigarette smoke, and has been implicated in multiple respiratory diseases.
Lung tissue is a primary target for acrolein toxicity in smokers and may lead to chronic lung inflammation and lung cancer.
Chronic inflammation, associated with expression of cyclooxygenase-2 (COX-2) and prostaglandins, are predisposing factors
for malignancy. In this study, we investigated the induction of COX-2 by acrolein in rat lung epithelial cells and its related
signaling cascade. Induction of COX-2 by acrolein was significant at 6 h post-treatment and was dependent upon NFκB activation.
The activation of NFκB by acrolein was induced as a result of degradation of IκBα over the time of treatment. In addition,
the upstream signaling cascade involved Raf-1/ERK activation by acrolein in the COX-2 induction and was inhibited by GW5074
(a Ras/Raf-1/ERK inhibitor), thereby providing evidence for the role of this cascade in this process. The results of these
studies offer an explanation for the mechanism of COX-2 induction by acrolein in rat lung epithelial cells. 相似文献
39.
Decolorization and partial degradation of monoazo dyes in sequential fixed-film anaerobic batch reactor (SFABR) 总被引:1,自引:0,他引:1
Decolorization of two monoazo dyes, acid orange 6 (AO6) and acid orange 7 (AO7), were studied in sequential fixed-film anaerobic batch reactor (SFABR) with varying dye concentrations and 500 mg/L glucose as the co-substrate. More than 90% dye decolorization could be achieved, even at 300 mg/L, with both AO6 and AO7 and dye decolorization rates were 168 mg/L/d and 176 mg/L/d, respectively. COD removals with these two monoazo dyes were significantly different, as 75% and 35% decrease were observed with AO6 and AO7, respectively. UV-visible spectral as well as HPLC analysis of SFABR treated effluent showed the accumulation of 4-aminobenzenesulfonate (4-ABS) from AO6 and AO7. Aminoresorcinol (AR) formed from AO6 decolorization could not be detected at the end of SFABR cycle. This along with high COD removal indicated its further degradation. Formation of pink coloration on exposure to air indicated the presence of 1-amino-2-naphthol (AN) in AO7 fed reactor effluent. Thus both 4-ABS and AN were resistant to further degradation under anaerobic conditions. Presence of nitrate did not decrease the observed decolorization at the end of 24h SFABR cycle, although initial rate was decreased. This indicates the suitability of SFABR configuration for the treatment of azo-dye containing wastewaters in the presence of nitrate. 相似文献