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1.
The isolation and structure determination of mikanokryptin, a stereoisomer of 11,13-dehydrogeigerin, from what appears to be a previously undescribed Mikania species is reported. Mikania micrantha HBK. yielded mikanolide and dihydromikanolide. 相似文献
2.
Gissi Novientri Mohamad Sadikin Sri Widia Jusman 《Reports of Biochemistry & Molecular Biology》2022,11(2):289
Background:Cytoglobin (Cygb) is a relatively newly identified globin protein that acts as an oxygen transporter in tissues like hemoglobin (Hb) in erythrocytes and myoglobin (Mb) in muscles. The natural oxidation of the Fe2+ ion in its heme group into metglobin (globin-Fe3+) made the loses of oxygen binding functions. It is known metHb and metMb can be reduced enzymatically using diaphorase or cyb5r3. However, metCygb reductase had not been previously identified. This study aims to analyze the reducing activity of bovine diaphorase on metCygb.Methods:Diaphorase was isolated from bovine erythrocyte and purified using gel filtration and cationic-exchanger chromatography. Its purity was verified by SDS-PAGE and western blot (WB). The metCygb was obtained from Cygb oxidation with potassium ferrocyanide and its reducing activity was determined by spectroscopy.Results:The diaphorase (MW=30.09 kDa) was purified 10.77-fold from crude enzyme with specific activity against metHb 8.479 U/mg. The purity was confirmed by WB using primary antibody anti-cyb5r3. The purified enzyme reduced metCygb at 0.785 µgmin-1, which was 13.7 times less than the Vmax of metHb.DiscussionIn conclusion, the purified diaphorase from bovine erythrocytes did not significantly reduce metCygb rather than metHb, a natural substrate in cells.Key Words: Bovine Erythrocyte, Cytochrome B5 Reductase, Diaphorase, Metcytoglobin, Reduction 相似文献
3.
Background and aims
Sustained interaction of advanced glycation end products (AGEs) with their receptor RAGE and subsequent signaling plays an important role in the development of diabetic complications. Genetic variation of RAGE gene may be associated with the development of vascular complications in type 2 diabetes mellitus (T2DM).Objectives
The present study aimed to explore the possible association of RAGE gene polymorphisms namely − 374T/A, − 429T/C and G82S with serum level of AGEs, paraoxonase (PON1) activity and macro-vascular complications (MVC) in Indian type 2 diabetes mellitus patients (T2DM).Methods
A total of 265 diabetic patients, including DM without any complications (n = 135), DM-MVC (n = 130) and 171 healthy individuals were enrolled. Genotyping of RAGE variants were assessed by polymerase chain reaction-restriction fragment length polymorphism. Serum AGEs were estimated by ELISA and fluorometrically. and PON1 activity was assessed spectrophotometrically.Results
Of the three examined SNPs, association of − 429T/C polymorphism with MVC in T2DM was observed (OR = 3.001, p = 0.001) in the dominant model. Allele ‘A’ of − 374T/A polymorphism seems to confer better cardiac outcome in T2DM. Patients carrying C allele (− 429T/C) and S allele (G82S) had significantly higher AGEs levels. − 429T/C polymorphism was also found to be associated with low PON1 activity. Interaction analysis revealed that the risk of development of MVC was higher in T2DM patients carrying both a CC genotype of − 429T/C polymorphism and a higher level of AGEs (OR = 1.343, p = 0.040).Conclusion
RAGE gene polymorphism has a significant effect on AGEs level and PON1 activity in diabetic subjects compared to healthy individuals. Diabetic patients with a CC genotype of − 429T/C are prone to develop MVC, more so if AGEs levels are high and PON1 activity is low. 相似文献4.
The availability of specific and reliable detection methods is essential for monitoring the health status of farmed species, particularly for viral diseases. Extra small virus (XSV), a virus-like particle, is associated with Macrobrachium rosenbergii Noda virus (MrNV) in white tail disease (WTD) of M. rosenbergii. We developed 2 genome-based detection methods for the identification of XSV, namely dot-blot hybridization and a single-step RT-PCR. Detection limits were established and are ca. 2.5 pg and 5 fg of viral RNA for dot-blot hybridization and RT-PCR, respectively. Application of the methods to field samples indicated that some animals positively diagnosed with MrNV did not contain XSV, at least within the detection limit of the methodology. This raises the question of the actual role of XSV and its interactions with MrNV in WTD of M. rosenbergii. 相似文献
5.
Crystal structure of a transcription regulator (TM1602) from Thermotoga maritima at 2.3 A resolution
Weekes D Miller MD Krishna SS McMullan D McPhillips TM Acosta C Canaves JM Elsliger MA Floyd R Grzechnik SK Jaroszewski L Klock HE Koesema E Kovarik JS Kreusch A Morse AT Quijano K Spraggon G van den Bedem H Wolf G Hodgson KO Wooley J Deacon AM Godzik A Lesley SA Wilson IA 《Proteins》2007,67(1):247-252
6.
Oroh Stery Brenda Mustopa Apon Zaenal Budiarti Sri Budiarto Bugi Ratno 《Molecular biology reports》2020,47(10):7567-7573
Molecular Biology Reports - Enteropathogenic Escherichia coli (EPEC) is a bioagent that causes diarrhea through the formation of biofilm. The recalcitrant of EPEC to the current conventional... 相似文献
7.
Widyanto Dwi Nugroho Satoshi Nakaba Yusuke Yamagishi Shahanara Begum Sri Nugroho Marsoem Jae-Heung Ko Hyun-O Jin Ryo Funada 《Annals of botany》2013,112(7):1321-1329
Background and Aims
Gibberellin stimulates negative gravitropism and the formation of tension wood in tilted Acacia mangium seedlings, while inhibitors of gibberellin synthesis strongly inhibit the return to vertical growth and suppress the formation of tension wood. To characterize the role of gibberellin in tension wood formation and gravitropism, this study investigated the role of gibberellin in the development of gelatinous fibres and in the changes in anatomical characteristics of woody elements in Acacia mangium seedlings exposed to a gravitational stimulus.Methods
Gibberellin, paclobutrazol and uniconazole-P were applied to the soil in which seedlings were growing, using distilled water as the control. Three days after the start of treatment, seedlings were inclined at 45 ° to the vertical and samples were harvested 2 months later. The effects of the treatments on wood fibres, vessel elements and ray parenchyma cells were analysed in tension wood in the upper part of inclined stems and in the opposite wood on the lower side of inclined stems.Key Results
Application of paclobutrazol or uniconazole-P inhibited the increase in the thickness of gelatinous layers and prevented the elongation of gelatinous fibres in the tension wood of inclined stems. By contrast, gibberellin stimulated the elongation of these fibres. Application of gibberellin and inhibitors of gibberellin biosynthesis had only minor effects on the anatomical characteristics of vessel and ray parenchyma cells.Conclusions
The results suggest that gibberellin is important for the development of gelatinous fibres in the tension wood of A. mangium seedlings and therefore in gravitropism. 相似文献8.
Online game is an increasingly popular source of entertainment for all ages, with relatively prevalent negative consequences. Addiction is a problem that has received much attention. This research aims to develop a measure of online game addiction for Indonesian children and adolescents. The Indonesian Online Game Addiction Questionnaire draws from earlier theories and research on the internet and game addiction. Its construction is further enriched by including findings from qualitative interviews and field observation to ensure appropriate expression of the items. The measure consists of 7 items with a 5-point Likert Scale. It is validated by testing 1,477 Indonesian junior and senior high school students from several schools in Manado, Medan, Pontianak, and Yogyakarta. The validation evidence is shown by item-total correlation and criterion validity. The Indonesian Online Game Addiction Questionnaire has good item-total correlation (ranging from 0.29 to 0.55) and acceptable reliability (α = 0.73). It is also moderately correlated with the participant''s longest time record to play online games (r = 0.39; p<0.01), average days per week in playing online games (ρ = 0.43; p<0.01), average hours per days in playing online games (ρ = 0.41; p<0.01), and monthly expenditure for online games (ρ = 0.30; p<0.01). Furthermore, we created a clinical cut-off estimate by combining criteria and population norm. The clinical cut-off estimate showed that the score of 14 to 21 may indicate mild online game addiction, and the score of 22 and above may indicate online game addiction. Overall, the result shows that Indonesian Online Game Addiction Questionnaire has sufficient psychometric property for research use, as well as limited clinical application. 相似文献
9.
Mohammad Aslam Sarla Aggarwal Krishna Kumar Sharma Vikas Galav Sri Venkata Madhu 《PloS one》2016,11(1)
Insulin resistance (IR) and type 2 diabetes mellitus (T2DM) have been found to be associated with postprandial hypertriglyceridemia (PPHTg). However, whether PPHTg can cause IR and diabetes is not clear. We therefore investigated the role of PPHTg in development of T2DM in rat model of T2DM. 96 male Wistar rats were randomized into four groups (24 rats each). Control Group A, high sucrose diet (HSD) Group B, HSD+Pioglitazone (10mg/kg/day) Group C and HSD+Atorvastatin (20mg/kg/day) Group D. Fat and glucose tolerance tests were done at regular intervals in all groups besides insulin and body weight measurement. At 26 weeks, low dose streptozotocin (15mg/kg,i.p.) was given to half of the rats. All rats were followed up till 48 weeks. PPHTg developed as early as week 2 in Group B and stabilized by week 14. Group B displayed highest PPHTg compared to other groups. Atorvastatin treatment (Group D) abolished PPHTg which became comparable to controls, pioglitazone treatment partially blunted PPHTg resulting in intermediate PPHTg. Group B with highest PPHTg showed highest subsequent IR, glucose intolerance (GI) and highest incidence of prediabetes at week 26 and diabetes at week 34 and 46 compared to other groups. Group D rats displayed lower IR, GI, low incidence of prediabetes and diabetes at these time points compared to Groups B and C. ROC analysis showed that triglyceride area under the curve of each time point significantly predicts the risk of diabetes. Present study provides the evidence that PPHTg predicts the development of IR, GI and T2DM in rat model of diet induced T2DM. 相似文献