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141.
142.
Waterlogging-induced increase in sugar mobilization, fermentation, and related gene expression in the roots of mung bean (Vigna radiata) 总被引:3,自引:0,他引:3
The objective of this study was to examine the role of root carbohydrate levels and metabolism in the waterlogging tolerance of contrasting mung bean genotypes. An experiment was conducted with two cultivated mung bean (Vigna radiata) genotypes viz., T44 (tolerant) and Pusa Baisakhi (PB) (susceptible), and a wild Vigna species Vigna luteola under pot-culture to study the physiological and molecular mechanism of waterlogging tolerance. Waterlogging resulted in decrease in relative water content (RWC), membrane stability index (MSI) in root and leaf tissues, and chlorophyll (Chl) content in leaves, while the Chl a/b ratio increased. Waterlogging-induced decline in RWC, MSI, Chl and increase in Chl a/b ratio was greater in PB than V. luteola and T44. Waterlogging caused decline in total and non-reducing sugars in all the genotypes and reducing sugars in PB, while the content of reducing sugar increased in V. luteola and T44. The pattern of variation in reducing sugar content in the 3 genotypes was parallel to sucrose synthase (SS) activity. V. luteola and T44 also showed fewer declines in total and non-reducing sugars and greater increase in reducing sugar and SS activity than PB. Activity of alcohol dehydrogenase (ADH) increased up to 8d of waterlogging in V. luteola and T44, while in PB a marginal increase was observed only up to 4d of treatment. Gene expression studies done by RT-PCR in 24h waterlogged plants showed enhanced expression of ADH and SS in the roots of V. luteola and T44, while in PB there was no change in expression level in control or treated plants. PCR band products were cloned and sequenced, and partial cDNAs of 531, 626, and 667; 702, 736, and 744bp of SS and ADH, respectively were obtained. The partial cDNA sequences of cloned SS genes showed 93-100 homologies among different genotypes and with D10266, while in case of ADH the similarity was in the range of 97-100% amongst each other and with Z23170. The results suggest that the availability of sufficient sugar reserve in the roots, activity of SS to provide reducing sugars for glycolytic activity and ADH for the recycling of NADH, and for the continuation of glycolysis, could be one of the important mechanisms of waterlogging tolerance of V. radiata genotype T44 and wild species V. luteola. This was reflected in better RWC and Chl content in leaves, and membrane stability of leaf and root tissue in V. luteola and T44. 相似文献
143.
144.
A new species of Lamiaceae, Teucrium ramaswamii M. B. Viswan. & U. Manik. is described from the Kalakkad-Mundanthurai Tiger Reserve (KMTR) in the Agastyamalai hills of the southwestern Ghats in peninsular India. It is allied to T. tomentosum Heyne ex Benth. but differs by stem, leaves and inflorescence being glandular strigose; leaves being deltoid–ovate, crenate–dentate or doubly crenate–dentate at margin, subcoriaceous, sparsely strigose above, densely strigose beneath; bracts being oblong–deltoid, ca 9.4×2.6 mm; calyx with uppermost teeth being lanceolate, ca 2.8×1.9 mm, lateral teeth being broadly triangular, lower teeth being oblong–lanceolate; corolla being glandular strigose outside below lateral lobes and ovary being glandular strigose. Using the IUCN criteria, conservation status of the species is assigned as Critically Endangered based on the field data (2000–2002). Life history studies, population ecology, genome resource banking and wild population management are recommended for conserving this species. 相似文献
145.
Rajaraman Swaminathan Ramanujam Selvakumaran Pulikattil Okkuru Esmy P. Sampath Jacques Ferlay Vinoda Jissa Viswanathan Shanta Mary Cherian Rengaswamy Sankaranarayanan 《Cancer epidemiology》2009,33(5):325-331
Background: Cancer pattern data are rare and survival data are none from rural districts of India. Methods: The Dindigul Ambilikkai Cancer Registry (DACR) covering rural population of 2 millions in Dindigul district, Tamil Nadu state, South India, registered 4516 incident cancers during 2003–2006 by active case finding from 102 data sources for studying incidence pattern, of which, 1045 incident cancers registered in 2003 were followed up for estimating survival. House visits were undertaken annually for each registered case for data completion. Cancer pattern was described using average annual incidence rates and survival experience was expressed by computing observed survival by actuarial method and age-standardized relative survival (ASRS). Results: The average annual age-standardized rate per 100,000 of all cancers together was higher among women (62.6) than men (51.9) in DACR. The most common cancers among men were stomach (5.6), mouth (4.2) and esophagus (3.7). Cervical cancer (22.1) was ranked at the top among women followed by breast (10.9) and ovary (3.3). DACR incidence rates were lesser by at least two folds and 5-year survival were on par or lower than Chennai metropolitan registry for most cancers. Five-year age-standardized relative survival (%) in DACR was as follows: all cancers (29%), larynx (48), mouth (42), breast/tongue (38) and cervix (37). Conclusion: Cancer incidence was significantly lower, cancer patterns were markedly different and population-based cancer survival was lower in rural areas than urban areas thus providing valuable leads in estimating realistic cancer burden and instituting cancer control programs in India. 相似文献
146.
Novel racemic 1-(4-hydroxyphenyl)-2-[3-(substituted phenoxy)-2-hydroxy-1-propyl]aminopropan-1-ol hydrochlorides (9a-h) were synthesized by condensing racemic 1-(p-hydroxyphenyl)-2-aminopropan-1-ol hydrochloride (6) with substituted aryloxymethyloxiranes (8a-h) in DMF in presence of anhydrous potassium carbonate and then reacting with dry hydrogen chloride gas. They were evaluated for uterine relaxant activity in vitro on isolated rat uterus and in vivo in pregnant rats. Their cAMP releasing potential was studied using rat uterus tissue homogenates by cAMP [3H] assay and cardiac stimulant potential was evaluated in dog. All compounds exhibited potent uterine relaxant activity in vitro and produced a significant delay in the onset of labour in pregnant rats; their cAMP releasing potential was higher than isoxsuprine hydrochloride except for 9b and 9c. Finally insignificant cardiac stimulant potential was noted for these compounds when compared to isoxsuprine hydrochloride. 相似文献
147.
Lokhande TN Viswanathan CL Joshi A Juvekar A 《Bioorganic & medicinal chemistry》2006,14(17):6022-6026
A novel class of molecules with structure N-[3-(4-substituted-1-piperazinyl) propyl]-6-methoxy naphthalene-2-carboxamides were designed by generating a pharmacophore for potent MDR reversal activity, using Elacridar (GF 120918) as a query molecule and using MOE software. They were synthesized by condensing 6-methoxynaphthalene-2-carboxylic acid with N-[3-(4-substituted-1-piperazinyl) propyl] amines in the presence of DCC in DMF. They were evaluated in P388 murine lymphocytic leukemia cell line (P388) in vitro using SRB assay for cytotoxicity and in adriamycin-resistant P388 murine lymphocytic leukemia cell line (P388/ADR) using MTT assay for resistant reversal activity. Test compounds were non-toxic at the doses studied (upto 80 microg/ml). They effectively reversed adriamycin resistance at the doses studied (40 and 80 microg/ml). The percentage enhancement in adriamycin activity was in the range 33.58 -90.67 (at 40 microg/ml) and 8.80-46.04 (at 80 microg/ml) and the corresponding reversal potency values were in the range 1.33-1.90 and 1.08-1.46, respectively. Test compounds 2, 3, and 5 exhibited better activity as compared to the standard resistant reversal agent (Verapamil), at same concentration. 相似文献
148.
Karthik Viswanathan Aarthi Chandrasekaran Aravind Srinivasan Rahul Raman V. Sasisekharan Ram Sasisekharan 《Glycoconjugate journal》2010,27(6):561-570
Influenza A viruses, members of the Orthomyxoviridae family, are responsible for annual seasonal influenza epidemics and occasional global pandemics. The binding of viral coat
glycoprotein hemagglutinin (HA) to sialylated glycan receptors on host epithelial cells is the critical initial step in the
infection and transmission of these viruses. Scientists believe that a switch in the binding specificity of HA from Neu5Acα2-3Gal
linked (α2-3) to Neu5Acα2-6Gal linked (α2-6) glycans is essential for the crossover of the viruses from avian to human hosts.
However, studies have shown that the classification of glycan binding preference of HA based on sialic acid linkage alone
is insufficient to establish a correlation between receptor specificity of HA and the efficient transmission of influenza
A viruses. A recent study reported extensive diversity in the structure and composition of α2-6 glycans (which goes beyond
the sialic acid linkage) in human upper respiratory epithelia and identified different glycan structural topologies. Biochemical
examination of the multivalent HA binding to these diverse sialylated glycan structures also demonstrated that high affinity
binding of HA to α2-6 glycans with a characteristic umbrella-like structural topology is critical for efficient human adaptation and human-human transmission of influenza A viruses. This
review summarizes studies which suggest a new paradigm for understanding the role of the structure of sialylated glycan receptors
in influenza virus pathogenesis. 相似文献
149.
Loveridge C Tonelli F Leclercq T Lim KG Long JS Berdyshev E Tate RJ Natarajan V Pitson SM Pyne NJ Pyne S 《The Journal of biological chemistry》2010,285(50):38841-38852
Sphingosine kinase 1 (SK1) is an enzyme that catalyzes the phosphorylation of sphingosine to produce the bioactive lipid sphingosine 1-phosphate (S1P). We demonstrate here that the SK1 inhibitor, SKi (2-(p-hydroxyanilino)-4-(p-chlorophenyl)thiazole) induces the proteasomal degradation of SK1 in human pulmonary artery smooth muscle cells, androgen-sensitive LNCaP prostate cancer cells, MCF-7 and MCF-7 HER2 breast cancer cells and that this is likely mediated by ceramide as a consequence of catalytic inhibition of SK1 by SKi. Moreover, SK1 is polyubiquitinated under basal conditions, and SKi appears to increase the degradation of SK1 by activating the proteasome. In addition, the proteasomal degradation of SK1a and SK1b in androgen-sensitive LNCaP cells is associated with the induction of apoptosis. However, SK1b in LNCaP-AI cells (androgen-independent) is less sensitive to SKi-induced proteasomal degradation and these cells are resistant to SKi-induced apoptosis, thereby implicating the ubiquitin-proteasomal degradation of SK1 as an important mechanism controlling cell survival. 相似文献
150.