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91.
In this study, loop-mediated isothermal amplification (LAMP)-based molecular marker was developed for authentication of Catharanthus roseus, a medicinal plant. Samples of this plant were collected from different geographical locations in India. Random amplified
polymorphic deoxyribonucleic acid (DNA) analysis of collected samples was carried out with 25 random primers. A 610-bp DNA
fragment, common to all accessions, was eluted, cloned, and sequenced. Four LAMP primers were designed on the basis of sequence
of 610 bp DNA fragment. LAMP reaction, containing 10× Bst DNA polymerase reaction buffer, Bst DNA polymerase, four in-house designed primers, dNTPs, MgSO4, and betaine, was incubated at 65°C for 1 h. The resulting amplicon was visualized by adding SYBR Green I to the reaction
tube. The data showed confirmatory results. Since the assay method is simple, sensitive, and cost-effective, it is a feasible
method for identifying and authentication of C. roseus. 相似文献
92.
Multicopper oxidase (MCO) is an enzyme which involves in reducing the oxygen in a four electron reduction to water with concomitant one electron oxidation of reducing the substrate. We have generated the 3-D structure of MCO by homology modeling and validated on the basis of free energy while 90.4 % amino acid residues present in allowed regions of Ramachandran plot. The screening of potential hazardous aromatic compounds for MCO was performed using molecular docking. We obtained Sulfonaphthal, Thymolphthalein, Bromocresol green and Phloretin derivatives of phenol and aromatic hydrocarbon were efficient substrates for MCO. The phylogeny of MCO reveals that other bacteria restrain the homologous gene of MCO may play an important role in biodegradation of aromatic compounds. We have demonstrated the gene regulatory network of MCO with other cellular proteins which play a key role in gene regulation. These findings provide a new insight for oxidization of phenolic and aromatic compounds using biodegradation process for controlling environmental pollution. 相似文献
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Autophagy is a process used for intracellular digestion of organelles and proteins and has special relevance to the long-lived
cardiomyocytes in heart disease. The pathway for autophagy and all its mediators remain to be elucidated, but involve such
proteins as Atg, Beclin-1, LAMP-2, BH3, Bcl2, PI3K Kinase as well as a plethora of others. It is still not entirely clear
whether autophagy is destructive or beneficial to the cell; evidence suggests that the answer is case-specific. For instance,
autophagy appears to preserve cell life under cases of ischemia in I/R injury, but is detrimental during reperfusion. High
levels of homocysteine (Hcy), a sulfur-containing amino acid, have been shown to be an independent risk factor for chronic
heart failure. There are several links to induction and repression of autophagy and Hcy; the following connections to Hcy
and autophagy have been made: intracellular nitrous oxide production, intracellular calcium production, and reactive oxygen
species production. Further work remains to be elucidated concerning the specific mechanisms under which autophagy occurs
and possible Hcy-mediated connections. Moreover, the therapeutic implications might be of some promise to patients. 相似文献
95.
Background: The acylation stimulating protein (ASP) is a potent lipogenic adipokine that correlates with postprandial triglyceride (TG) clearance and is linked to the pathophysiology of obesity and related disorders. Objective: To investigate ASP levels in cord blood and its relation to maternal and cord blood lipid parameters and fetal birth weight. Methods and Procedures: Thirty nondiabetic pregnant women, their newborns, and thirty‐three nonpregnant controls were included in this study. Fasting maternal and cord blood ASP, TGs, nonesterified fatty acids (NEFAs), cholesterol, glucose levels, in addition to maternal BMI and fetal birth weight were measured. Results: No significant difference was found between cord blood ASP (16.3 ± 0.96 nmol/l) and ASP levels in the adult controls (15.7 ± 1.0 nmol/l). Cord blood ASP, however, was lower than maternal plasma ASP levels (25.4 ± 1.6 nmol/l, P < 0.001). Yet, lipid levels in cord blood, particularly TGs were markedly decreased compared to control and maternal TG levels (threefold and 7.4‐fold, P < 0.001 respectively). Maternal TGs significantly correlated with fetal birth weight (r = 0.54, P = 0.002). Multiple regression analysis showed that maternal TGs (β = 0.57, P = 0.01) and NEFAs (β = 0.43, P = 0.024) predicted 45% variation in cord blood ASP levels, independent of all measured maternal and cord blood parameters. Cord blood ASP showed a positive correlation with fetal birth weight (r = 0.524, P = 0.037) in neonates above average fetal birth weight of the studied population. Discussion: This is the first study investigating ASP in cord blood. We suggest that maternal hypertriglyceridemia is associated with increased fetal ASP production, thus enhancing fetal fat storage independent of maternal glucose variations in nondiabetic women. 相似文献
96.
Moshal KS Zeldin DC Sithu SD Sen U Tyagi N Kumar M Hughes WM Metreveli N Rosenberger DS Singh M Vacek TP Rodriguez WE Ayotunde A Tyagi SC 《Journal of cellular physiology》2008,215(3):771-781
Hyperhomocysteinemia (HHcy) is associated with atherosclerotic events involving the modulation of arachidonic acid (AA) metabolism and the activation of matrix metalloproteinase-9 (MMP-9). Cytochrome P450 (CYP) epoxygenase-2J2 (CYP2J2) is abundant in the heart endothelium, and its AA metabolites epoxyeicosatrienoic acids (EETs) mitigates inflammation through NF-kappabeta. However, the underlying molecular mechanisms for MMP-9 regulation by CYP2J2 in HHcy remain obscure. We sought to determine the molecular mechanisms by which P450 epoxygenase gene transfection or EETs supplementation attenuate homocysteine (Hcy)-induced MMP-9 activation. CYP2J2 was over-expressed in mouse aortic endothelial cells (MAECs) by transfection with the pcDNA3.1/CYP2J2 vector. The effects of P450 epoxygenase transfection or exogenous supplementation of EETs on NF-kappabeta-mediated MMP-9 regulation were evaluated using Western blot, in-gel gelatin zymography, electromobility shift assay, immunocytochemistry. The result suggested that Hcy downregulated CYP2J2 protein expression and dephosphorylated PI3K-dependent AKT signal. Hcy induced the nuclear translocation of NF-kappabeta via downregulation of IKbetaalpha (endogenous cytoplasmic inhibitor of NF-kappabeta). Hcy induced MMP-9 activation by increasing NF-kappabeta-DNA binding. Moreover, P450 epoxygenase transfection or exogenous addition of 8,9-EET phosphorylated the AKT and attenuated Hcy-induced MMP-9 activation. This occurred, in part, by the inhibition of NF-kappabeta nuclear translocation, NF-kappabeta-DNA binding and activation of IKbetaalpha. The study unequivocally suggested the pivotal role of EETs in the modulation of Hcy/MMP-9 signal. 相似文献
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