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51.
M K Gupta H V Chauhan G J Jha K K Singh 《Indian journal of experimental biology》1990,28(11):1021-1025
Dinitrofluorobenzene (DNFB) contact-sensitivity test and leucocyte adherence inhibition (LAI) test were performed in this study as in vivo and in vitro tests to measure the cell-mediated immunity (CMI) in chickens subjected to stimulation of reticuloendothelial (RE) system, depletion of RE system and other experimental groups after being challenged with Marek's disease (MD) virus. It was found that CMI was lower in the birds with depleted RE system and infected control birds, whereas CMI was higher in the birds with activated RE system and vaccinated birds as revealed by DNFB contact-sensitivity test. In cases of LAI test, the number of LAI-positive birds were highest in the chicks with depleted RE system particularly in 3rd and 4th month of age, when the incidence of MD was also maximum. 相似文献
52.
The enzymes involved in the protection of plant metabolism in presence of azo dye was characterized by studying activities of the role of antioxidant enzymes in the hairy roots (HRs) of Physalis minima L. during degradation of an azo dye, Reactive Black 8 (RB8). When the HRs were exposed to RB8 (30 mg L?1), a nine fold increase in SOD activity was observed after 24 h, while 22 and 50 fold increase in activity was observed for POX and APX respectively after 72 h, whereas there was no significant change in activity of CAT. The activation of different antioxidant enzymes at different time intervals under dye stress suggests the synchronized functioning of antioxidant machinery to protect the HRs from oxidative damage. FTIR analysis confirmed the degradation of dye and the non-toxic nature of metabolites formed after dye degradation was confirmed by phytotoxicity study. 相似文献
53.
Anjana Devkota Stefano Dall'Acqua Stefano Comai Gabbriella Innocenti Pramod Kumar Jha 《Biochemical Systematics and Ecology》2010
Centella asiatica (L.) Urban is widely used in traditional medicine in many countries and in the formulation of drugs and cosmetics, and is therefore suitable as a trade item for the development of medicinal plants for the population of Nepal. The aim of this work was to select plant populations of C. asiatica with high contents of secondary metabolites growing in various localities in Nepal, and to enhance knowledge of the cultivation of this plant. Quali-quantitative analysis of bioactive triterpenes (asiaticoside and asiatic acid) and phenol derivatives (flavonoids and caffeoyl esters) was performed by HPLC-DAD-ELSD. The highest quantities of triterpenes and phenols were found in samples from the Gorkha and Chitwan districts. Regarding cultivated plants, soil fertilisation is critical, since over-rich soils affect secondary metabolite content. Plants growing in sand-rich soils produce more terpenes. This work provides indications on how to select high-terpene producing germplasm and recommendations for plant cultivation. 相似文献
54.
Natwar Singh Avinash Mishra Mukul Joshi Bhavanath Jha 《Plant Cell, Tissue and Organ Culture》2010,103(1):1-6
Pre-cultured cumin embryos were bombarded under 27 inches Hg vacuum, 25 mm distance from rupture disc to macrocarrier, 10 mm
macrocarrier flight distance using 1100 psi rupture disc and 9 cm microprojectile travel distance. An average of 110 embryos
was used per shot and 91% embryos showed transient GUS expression after 24 h. Shoot tips and roots of T0 plantlets exhibited GUS expression done after 3 months of bombardment. Transformation was confirmed with PCR amplification
of 0.96 and 1.3 kb band of hptII and gus genes respectively from T0 transgenics and southern blot analysis using PCR amplified DIG labeled hptII gene as probe. It is the first successful attempt of transformation of cumin plant through direct gene transfer using particle
gene gun and adequately exhibiting the possibility of stable transformation in cumin. 相似文献
55.
56.
Acetylcholine receptor gating at extracellular transmembrane domain interface: the cys-loop and M2-M3 linker 下载免费PDF全文
Acetylcholine receptor channel gating is a propagated conformational cascade that links changes in structure and function at the transmitter binding sites in the extracellular domain (ECD) with those at a "gate" in the transmembrane domain (TMD). We used Phi-value analysis to probe the relative timing of the gating motions of alpha-subunit residues located near the ECD-TMD interface. Mutation of four of the seven amino acids in the M2-M3 linker (which connects the pore-lining M2 helix with the M3 helix), including three of the four residues in the core of the linker, changed the diliganded gating equilibrium constant (K(eq)) by up to 10,000-fold (P272 > I274 > A270 > G275). The average Phi-value for the whole linker was approximately 0.64. One interpretation of this result is that the gating motions of the M2-M3 linker are approximately synchronous with those of much of M2 (approximately 0.64), but occur after those of the transmitter binding site region (approximately 0.93) and loops 2 and 7 (approximately 0.77). We also examined mutants of six cys-loop residues (V132, T133, H134, F135, P136, and F137). Mutation of V132, H134, and F135 changed K(eq) by 2800-, 10-, and 18-fold, respectively, and with an average Phi-value of 0.74, similar to those of other cys-loop residues. Even though V132 and I274 are close, the energetic coupling between I and V mutants of these positions was small (< or =0.51 kcal mol(-1)). The M2-M3 linker appears to be the key moving part that couples gating motions at the base of the ECD with those in TMD. These interactions are distributed along an approximately 16-A border and involve about a dozen residues. 相似文献
57.
Williams KD Blangero J Cottom CR Lawrence S Choh AC Czerwinski SA Lee M Duren DL Sherwood RJ Dyer TD Jha B Subedi J Williams-Blangero S Towne B 《Human biology; an international record of research》2007,79(6):609-622
Brachymesophalangia-V (BMP-V), a short and broad middle phalanx of the fifth digit, is the most common of all skeletal anomalies of the hand. When this feature appears alone, it is clinically known as brachydactyly type A3 (BDA3). A high prevalence of BDA3 has been observed among the children of the Jirel ethnic group in eastern Nepal. As part of the Jiri Growth Study, a hand-wrist radiograph is taken annually of each child to assess skeletal development. For this study the most recent radiographs of 1,357 Jirel children, adolescents, and young adults (676 boys, 681 girls), age 3-20 years, were examined for the presence or absence of BDA3, to report the prevalence and estimate the heritability of BDA3 in the Jirel population. The overall prevalence of BDA3 in this sample was 10.5% (12.9% of the males and 8.9% of the females were classified as BDA3 affected). The additive genetic heritability of BDA3 was statistically significant in this sample (h2 +/- SE = 0.87 +/- 0.16, p < 0.0001). This study is the first to estimate the prevalence and heritability of BDA3 in a large South Asian family-based sample. 相似文献
58.
Youssef D Nichols CE Cameron TS Balzarini J De Clercq E Jha A 《Bioorganic & medicinal chemistry letters》2007,17(20):5624-5629
A series of novel cyclic analogues of curcumin were synthesized and analyzed for in vitro cytostatic activity. Condensation of 2-acetylcycloalkanones with a variety of aromatic aldehydes resulted in the formation of 2-arylidene-6-(3-arylacryoyl)-cycloalkanone derivatives. A number of these analogues were found to have significant anticancer activity against representative murine and human cancer cell lines during in vitro bioassays. This corroborated with in vitro cytostatic activity against a panel of 60 cell lines studied at the National Cancer Institute (USA). 相似文献
59.
Fitzgerald JE Jha AK Colubri A Sosnick TR Freed KF 《Protein science : a publication of the Protein Society》2007,16(10):2123-2139
We developed a series of statistical potentials to recognize the native protein from decoys, particularly when using only a reduced representation in which each side chain is treated as a single C(beta) atom. Beginning with a highly successful all-atom statistical potential, the Discrete Optimized Protein Energy function (DOPE), we considered the implications of including additional information in the all-atom statistical potential and subsequently reducing to the C(beta) representation. One of the potentials includes interaction energies conditional on backbone geometries. A second potential separates sequence local from sequence nonlocal interactions and introduces a novel reference state for the sequence local interactions. The resultant potentials perform better than the original DOPE statistical potential in decoy identification. Moreover, even upon passing to a reduced C(beta) representation, these statistical potentials outscore the original (all-atom) DOPE potential in identifying native states for sets of decoys. Interestingly, the backbone-dependent statistical potential is shown to retain nearly all of the information content of the all-atom representation in the C(beta) representation. In addition, these new statistical potentials are combined with existing potentials to model hydrogen bonding, torsion energies, and solvation energies to produce even better performing potentials. The ability of the C(beta) statistical potentials to accurately represent protein interactions bodes well for computational efficiency in protein folding calculations using reduced backbone representations, while the extensions to DOPE illustrate general principles for improving knowledge-based potentials. 相似文献
60.
Jha A Mukherjee C Prasad AK Parmar VS Clercq ED Balzarini J Stables JP Manavathu EK Shrivastav A Sharma RK Nienaber KH Zello GA Dimmock JR 《Bioorganic & medicinal chemistry》2007,15(17):5854-5865
A series of E,E,E-3,5-bis(arylidene)-1-(4-arylamino-4-oxo-2-butenoyl)-4-piperidones 4 (phenylidene) and 5 (4-nitrophenylidene) were prepared in order to explore the structural features of the N-acyl group which affects the cytotoxic potency. Evaluation toward human Molt 4/C8 and CEM T-lymphocytes revealed that many of the IC(50) figures were submicromolar and lower than melphalan. Marked inhibitory potencies toward murine leukemia L1210 cells were also noted. When evaluated against a panel of human tumor cell lines, three representative compounds in series 4 displayed selective toxicity to leukemia and colon cancer cell lines and were significantly more potent than the reference drug melphalan. Molecular modeling of representative compounds in both series 4 and the analogs, in which the configuration of the olefinic double bond was changed from E to Z (series 3), revealed that the torsion angles of the arylidene aryl rings and locations of the terminal arylaminocarbonyl groups may have contributed to the greater cytotoxic properties displayed in 3. Compounds 4c (3,4-dichlorophenylamino), d (4-methylphenylamino) and 5c (3,4-dichlorophenylamino), d (4-methylphenylamino) inhibited the activity of human N-myristoyltransferase by approximately 50% at concentrations of 50-100 microM. The compounds in series 4 and 5 were well tolerated in a short-term toxicity study in mice. 相似文献