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Zone Precipitation Chromatography is useful tech-nique for the initial isolation of the different colla-gen types in their native configuration. Small quan-tities of collagen mixtures can be rapidly separated into different collagen types with relatively high degree of purity, based upon stained protein patterns on sodium dodecyl sulfate polyacrylamide gel electro-phoresis (SDS-PAGE) slab gels. Tn the commonly used bulk salt preparative method for isolating the different collagens, 50 mg of starting material was needed. Three days were required to complete the procedure. The stained protein patterns on SDS-PAGE slab gels showed about 25% contamination with the bulk purified Type III fraction and 20% contamination with the bulk purified type AB collagen. With Zone Precipitation Chromatography 5 mg of starting material was used and in less than 4 hours the mixture was separated with Types III and AB fractions showing less than 10% contamination from other collagen types. The technique is patterned after the Zone Precinitation method reported by Porath seventeen years ago and utilizes a step-wise sodium chloride gradient to precipitate and redissolve the collagens, eluting from the interbead spaces of a molecular sieve column.  相似文献   
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Changes in RNA and protein contents, and protein profiles were studied in the rhizomes of turmeric (Curcuma longa L.) from the day of harvest to the commencement of sprouting. Protein and RNA contents increased gradually in the initial stages and rapidly in the final stages of storage period. SDS-PAGE analysis of storage proteins revealed synthesis of 56, 52 and 47 kDa proteins during the later stages of storage with concomitant disintegration of 23 and 18 kDa proteins.  相似文献   
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Recently, we reported that the herbal drug St. John's Wort is a potent inhibitor of UV-induced HIV-LTR activation in stably transfected HIVcat/HeLa cells [35]. Our previous studies have demonstrated that the activation of p38 MAP kinase (stress-activated protein kinase-2) and NF-B are both required for a full UV-induced HIV gene expression response. In this study we have investigated the mechanism by which curcumin inhibits UV-activated HIV-LTR gene expression. We found that treatment of HIVcat/HeLa cells with micromolar concentrations of curcumin completely abolished UV activation of HIV gene expression. Curcumin treatment at similar doses as those used to inhibit HIV gene expression also effectively blocked UV activation of NF-B, as demonstrated by electrophoretic mobility shift assay. In contrast, curcumin did not inhibit UV-induced phosphorylation of p38 MAP kinase. This observation was also supported by findings that curcumin did not inhibit UV-induced phosphorylation of CREB/ATF-1 and ATF-2. Although curcumin was ineffective in preventing UV-induced p44/42 MAP kinase phosphorylation, the JNK (1 and 2) and AP-1 activation were efficiently blocked by curcumin in HeLa cells. We conclude that the mechanism by which curcumin modulates UV activation of HIV-LTR gene expression mainly involves the inhibition of NF-B activation.  相似文献   
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Diet is now one of the well established means in the management of diabetes. Bitter gourd and spent turmeric at 10% level were tested for their efficacy on glycosaminoglycan metabolism in various tissues viz., liver, spleen, lungs, heart and testis in control, diabetic and treated rats. The glycosaminoglycans (GAGs) were isolated from defatted and dried tissues. The contents of sulfated GAGs decreased in all the tissues and the decrease was more prominent in heart and testis. In the isolated GAGs, contents of total sugar, amino sugar, uronic acid and sulfate were studied. Decrease in total sugar content was maximum in testis. Amino sugar content decreased considerably in testis (38%) and lungs (15%). The content of uronic acid also decreased in testis (33%) besides heart (29%) and liver (25%). Sulfate groups in GAGs perform pivotal functions in many biological events and decrease in sulfate content was significant in heart (40%), testis (37%) and liver (37%). GAGs profile on the cellulose acetate electrophoresis revealed that heparan sulfate (HS), hyaluronic acid (HA) and chondroitin sulfate/dermatan sulfate (CS/DS) were present in liver, spleen and lungs. HS, CS were present in heart, DS/CS was observed in testis. The observed beneficial effects in GAGs metabolism during diabetes may be due to the presence of high amounts of dietary fibres present in bitter gourd and spent turmeric, besides, possible presence of bioactive compounds in one or both of them.  相似文献   
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The effect of retinol deficiency and curcumin and turmeric feeding on brain microsomal Na+-K+ ATPase activity was investigated. The brain Na+–K+ ATPase activity registered an increase of 148.5% as compared to the control group. Upon treating retinol deficient rats with curcumin or turmeric, the abnormally elevated activity showed a decrease of 36.9 and 47.1%, respectively, when compared to the retinol deficient group. An increase in Vmax by 67% and Km by 66% for ATP was observed in the retinol deficient group. Curcumin or turmeric fed retinol-deficient groups reduced the Vmax by 25 and 33%, while Km was reduced by 25 and 31%, respectively, compared to the retinol deficient group. Arrhenius plot of Na+–K+ ATPase showed a typical bi-phasic pattern in all the groups. Cholesterol: Phospholipid ratio showed a decrease in the retinol-deficient group by 67.8%, which showed a marked increase in curcumin or turmeric treated groups. Detergents could increase the Na+–K+ ATPase activity more in the control group than in the retinol deficient groups. Curcumin or turmeric improved the detergent action on the enzyme. Subsequent freezing and thawing over a period of 30 min decreased the enzyme activity by 22.8% in the retinol deficient group compared to 15.9% decrease in the control group. Curcumin or turmeric treated groups showed a decrease in the enzyme activity by 22.0 and 19.2%, respectively, when compared to the zero time in each group. In the presence of concanavalin-A (Con-A) there was only 52.4% stimulation in the enzyme activity in retinol deficient groups, compared to 108.0% in the control group. Curcumin or turmeric treated retinol-deficient groups showed a stimulation in the presence of con-A by 70 and 99.5%, respectively.  相似文献   
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The relationships between genome size and the systematic and evolutionary patterns in vascular plants are equivocal, although a close relationship between genome size and evolutionary patterns has been previously reported. However, several studies have also revealed the dynamic nature of genome size evolution and its considerable ‘ups’ and ‘downs’. Thus, in this study, the phylogenetic relationships among three previously revealed genome size groups and among species of the highly polyploid genus Curcuma were evaluated using AFLP. Our results suggest two main lineages within Indian Curcuma reflecting evolution of genome size. The first one includes hexaploids and higher polyploids of the previously recognized genome size group I, and the second one includes mainly hexaploids of genome size groups II and III. Within genome size group I, relationships among species seem to be influenced by reticulate evolution and higher polyploids are likely to be of allopolyploid origin. Reproductive systems in Indian Curcuma vary considerably among ploidy levels and these differences considerably affect morphological and genetic variation. In general, clonally reproducing species are expected to exhibit low genotypic diversity, but, at the same time, species of allopolyploid origin are expected to maintain higher levels of heterozygosity compared with their progenitors. We investigated intra‐populational genetic variability in Curcuma spp. to evaluate whether mode of reproduction or ploidy represent the main factor influencing the degree of genetic diversity. We found that hexaploid species exhibited significantly higher genetic diversity than higher polyploids (9x, 15x). Our results suggest that this genetic diversity pattern is largely influenced by the mode of reproduction, as higher polyploids reproduce exclusively vegetatively, whereas hexaploids reproduce mainly sexually. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 165 , 388–401.  相似文献   
9.
莪术油滴眼液体内外抗菌和抗病毒作用的药效学研究   总被引:3,自引:0,他引:3  
拟了解莪术油滴眼液(ZTO)体内外抗菌、抗病毒效果。实验结果显示,ZTO完全抑制HSV-1和ADV- 3对细胞CPE的最低浓度均为64μg/mL;ZTO对50株革兰阳性菌MIC_(90)和MBC值分别为128μg/mL和256μg/mL,对100株革兰阴性菌的MIC_(90)和MBC值分别为64~512μg/mL和128~>512μg/mL。2 mg/mL或1 mg/mL的ZTO分别治疗金黄色葡萄球菌感染和HSV-1感染兔眼结膜炎的有效率均可达到100%,与抗菌对照药氯霉素滴眼液和抗病毒对照药阿昔洛韦滴眼液的疗效无显著性差异(P>0.05)。实验数据表明,ZTO体外抗菌和抗病毒作用较弱,但体内抗菌和抗病毒作用较强,具有进一步开发为能同时具有抗菌和抗病毒的治疗眼结膜炎外用新药的良好前景。  相似文献   
10.
Callus cultures were initiated from leaf bases of turmeric on Murashige and Skoog's basal medium (MS) supplemented with dicamba, picloram (2 mg l−1) or 1-naphthaleneacetic acid (NAA) (5 mg l−1) in combination with benzyladenine (BA) (0.5 mg l−1). On transfer of callus cultures to medium supplemented with benzyladenine (BA) (5 mg l−1) in combination with triiodebenzoic acid (TIBA) or 2,4-dichlorophenoxyacetic acid (2,4-D) (0.1 mg l−1), green shoot primordia were seen to differentiate from the surface of the callus. On transfer of regenerating cultures to half MS media supplemented with Kn, shoot primordia developed into well developed shoots. When shoots were transferred to medium devoid of phytohormones, complete rooted plants were obtained. Ninety percent of the plants survived to maturity on transfer to soil. Random Amplified Polymorphic DNA (RAPD) analysis of eight regenerated plants using 14 primers when separated on non-denaturing polyacrylamide gels showed 38 novel bands. About 51 bands present in the control were absent in the regenerants. The result indicates that variation at DNA level has occurred during in vitro culture. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
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