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51.
Ramadurai Gowrishankar Manish Kumar Vinay Menon Sai Mangala Divi M. Saravanan P. Magudapathy B. K. Panigrahi K. G. M. Nair K. Venkataramaniah 《Biological trace element research》2010,133(3):357-363
Traditionally, Tinospora cordifolia (Willd.) Hook. F. & Thomson (Menispermaceae), Ocimum sanctum L. (Lamiaceae), Moringa oleifera Lam. (Moringaceae), and Phyllanthus niruri L. (Euphorbiaceae) are some of the commonly used medicinal plants in India for curing ailments ranging from common cold,
skin diseases, and dental infections to major disorders like diabetes, hypertension, jaundice, rheumatism, etc. To understand
and correlate their medicinal use, trace element studies on the aqueous extract of these medicinal plants have been carried
out using particle-induced X-ray emission technique. A 2-MeV proton beam was used to identify and characterize major and minor
elements namely Cl, K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Br, and Sr in them. Results have revealed that these elements are
present in varying concentrations in the selected plants. Notable results include very high concentrations of Cl, K, and Ca
in all the leaf samples, appreciable levels of Mn in all plants, high Zn content in T. cordifolia, and the aqueous extract of Moringa leaves compared to others and relative higher concentrations of Cr in all the plants. 相似文献
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Mukherjee M Chow SY Yusoff P Seetharaman J Ng C Sinniah S Koh XW Asgar NF Li D Yim D Jackson RA Yew J Qian J Iyu A Lim YP Zhou X Sze SK Guy GR Sivaraman J 《The EMBO journal》2012,31(5):1308-1319
Phosphotyrosine-binding domains, typified by the SH2 (Src homology 2) and PTB domains, are critical upstream components of signal transduction pathways. The E3 ubiquitin ligase Hakai targets tyrosine-phosphorylated E-cadherin via an uncharacterized domain. In this study, the crystal structure of Hakai (amino acids 106-206) revealed that it forms an atypical, zinc-coordinated homodimer by utilizing residues from the phosphotyrosine-binding domain of two Hakai monomers. Hakai dimerization allows the formation of a phosphotyrosine-binding pocket that recognizes specific phosphorylated tyrosines and flanking acidic amino acids of Src substrates, such as E-cadherin, cortactin and DOK1. NMR and mutational analysis identified the Hakai residues required for target binding within the binding pocket, now named the HYB domain. ZNF645 also possesses a HYB domain but demonstrates different target specificities. The HYB domain is structurally different from other phosphotyrosine-binding domains and is a potential drug target due to its novel structural features. 相似文献
55.
Substituting dietary linoleic acid with alpha-linolenic acid improves insulin sensitivity in sucrose fed rats 总被引:3,自引:0,他引:3
This study describes the effect of substituting dietary linoleic acid (18:2 n-6) with alpha-linolenic acid (18:3 n-3) on sucrose-induced insulin resistance (IR). Wistar NIN male weanling rats were fed casein based diet containing 22 energy percent (en%) fat with approximately 6, 9 and 7 en% saturated fatty acids (SFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) respectively for 3 months. IR was induced by replacing starch (ST) with sucrose (SU). Blends of groundnut, palmolein, and linseed oil in different proportions furnished the following levels of 18:3 n-3 (g/100 g diet) and 18:2 n-6/18:3 n-3 ratios respectively: ST-220 (0.014, 220), SU-220 (0.014, 220), SU-50 (0.06, 50), SU-10 (0.27, 10) and SU-2 (1.1, 2). The results showed IR in the sucrose fed group (SU-220) as evidenced by increase in fasting plasma insulin and area under the curve (AUC) of insulin in response to oral glucose load. In SU-220, the increase in adipocyte plasma membrane cholesterol/phospholipid ratio was associated with a decrease in fluidity, insulin stimulated glucose transport, antilipolytic effect of insulin and increase in basal and norepinephrine stimulated lipolysis in adipocytes. In SU-50, sucrose induced alterations in adipocyte lipolysis and antilipolysis were normalized. However, in SU-2, partial corrections in plasma insulin, AUC of insulin and adipocyte insulin stimulated glucose transport were observed. Further, plasma triglycerides and cholesterol decreased in SU-2. In diaphragm phospholipids, the observed dose dependent increase in long chain (LC) n-3 PUFA was associated with a decrease in LC-n-6 PUFA but insulin stimulated glucose transport increased only in SU-2. Thus, this study shows that the substitution of one-third of dietary 18:2 n-6 with 18:3 n-3 (SU-2) results in lowered blood lipid levels and increases peripheral insulin sensitivity, possibly due to the resulting high LCn-3 PUFA levels in target tissues of insulin action. These findings suggest a role for 18:3 n-3 in the prevention of insulin resistant states. The current recommendation to increase 18:3 n-3 intake for reducing cardiovascular risk may also be beneficial for preventing IR in humans. 相似文献
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Chakravorty D Parameswaran S Dubey VK Patra S 《Extremophiles : life under extreme conditions》2011,15(1):89-103
Thermostable lipases are of high priority for industrial applications as they are endowed with the capability of carrying
out diversified reactions at elevated temperatures. Extremophiles are their potential source. Sequence and structure annotation
of thermostable lipases can elucidate evolution of lipases from their mesophilic counterparts with enhanced thermostability
hence better industrial potential. Sequence analysis highlighted the conserved residues in bacterial and fungal thermostable
lipases. Higher frequency of AXXXA motif and poly Ala residues in lid domain of thermostable Bacillus lipases were distinguishing characteristics. Comparison of amino acid composition among thermostable and mesostable lipases
brought into light the role of neutral, charged and aromatic amino acid residues in enhancement of thermostability. Structural
annotation of thermostable lipases with that of mesostable lipases revealed some striking features which are increment of
gamma turns in thermostable lipases; being first time reported in our paper, longer beta strands, lesser beta-branched residues
in helices, increase in charged-neutral hydrogen bonding pair, hydrophobic-hydrophobic contact and differences in the N-cap
and C-cap residues of the α helices. Conclusively, it can be stated that subtle changes in the arrangement of amino acid residues
in the tertiary structure of lipases contributes to enhanced thermostability. 相似文献
58.
Ahamed Ibrahim Saravanan Natarajan 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2005,1733(1):67-75
This study describes the effect of substituting dietary linoleic acid (18:2 n-6) with α-linolenic acid (18:3 n-3) on sucrose-induced insulin resistance (IR). Wistar NIN male weanling rats were fed casein based diet containing 22 energy percent (en%) fat with ~6, 9 and 7 en% saturated fatty acids (SFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) respectively for 3 months. IR was induced by replacing starch (ST) with sucrose (SU). Blends of groundnut, palmolein, and linseed oil in different proportions furnished the following levels of 18:3 n-3 (g/100 g diet) and 18:2 n-6/18:3 n-3 ratios respectively: ST-220 (0.014, 220), SU-220 (0.014, 220), SU-50 (0.06, 50), SU-10 (0.27, 10) and SU-2 (1.1, 2). The results showed IR in the sucrose fed group (SU-220) as evidenced by increase in fasting plasma insulin and area under the curve (AUC) of insulin in response to oral glucose load. In SU-220, the increase in adipocyte plasma membrane cholesterol/phospholipid ratio was associated with a decrease in fluidity, insulin stimulated glucose transport, antilipolytic effect of insulin and increase in basal and norepinephrine stimulated lipolysis in adipocytes. In SU-50, sucrose induced alterations in adipocyte lipolysis and antilipolysis were normalized. However, in SU-2, partial corrections in plasma insulin, AUC of insulin and adipocyte insulin stimulated glucose transport were observed. Further, plasma triglycerides and cholesterol decreased in SU-2. In diaphragm phospholipids, the observed dose dependent increase in long chain (LC) n-3 PUFA was associated with a decrease in LC-n-6 PUFA but insulin stimulated glucose transport increased only in SU-2. Thus, this study shows that the substitution of one-third of dietary 18:2 n-6 with 18:3 n-3 (SU-2) results in lowered blood lipid levels and increases peripheral insulin sensitivity, possibly due to the resulting high LCn-3 PUFA levels in target tissues of insulin action. These findings suggest a role for 18:3 n-3 in the prevention of insulin resistant states. The current recommendation to increase 18:3 n-3 intake for reducing cardiovascular risk may also be beneficial for preventing IR in humans. 相似文献
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Secondary toxcity of difethialone to Barn owl (Tyto alba) has been investigated. Difethialone was fed to owls for successive periods of 1 (phase 1), 3 (phase 2) and 6 (phase 3) days via-rodenticide dosed rats. The owls survived after the treament of rodenticide on phase 1 and phase 2 experiments but they died during phase 3 experiment. The results suggest that the difethialone could cause more secondary toxicity to owls. 相似文献