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991.
Danshen (Salviae Miltiorrhizae Radix) and Gegen (Puerariae Lobatae Radix) have been widely used in treating cardiovascular diseases for thousands of years in China. The present study was carried out to evaluate the effects of a Danshen and Gegen decoction (DG) on the vascular reactivity of a porcine isolated coronary artery and the underlying mechanisms involved. Porcine coronary rings were precontracted with 15nM U46619. The involvement of endothelium-dependent mechanisms was explored by removing the endothelium; the involvement of potassium channels was investigated by the pretreatment of the artery rings with various blockers, and the involvement of the calcium channels was investigated by incubating the artery rings with Ca(2+)-free buffer and priming them with high [K(+)] prior to adding CaCl(2) to elicit contraction. The involvement of Ca(2+) sensitization was explored by evaluating the Rho-activity expression. The results revealed that DG elicited a concentration-dependent relaxation on a U46619-precontracted coronary artery ring. These relaxation responses were not altered by the pretreatment of inhibitors of endothelium-related dilator synthases, cGMP and cAMP pathway inhibitors, potassium channel (BK(Ca), SK(Ca), K(V) and K(ATP)) blockers and endothelium removal. The K(IR) channel blocker BaCl(2) only slightly attenuated the DG-induced relaxation. However, the Ca(2+)-induced artery contraction was inhibited by DG. Additionally, the expression of the phosphorylated myosin light chain was inhibited by DG whereas the activity of RhoA was not affected. Therefore, DG could be a useful cardioprotective agent for vasodilation in patients who have hypertension. 相似文献
992.
Diabetes mellitus (DM) often leads to disability from vascular complications and neurological complications. Tinospora crispa has been widely used in Asia and Africa as a remedy for diabetes and other diseases. In this study, we investigated the hypoglycemic actions of borapetoside C isolated from T. crispa, and the mechanisms underlying its actions. Acute treatment with borapetoside C (5mg/kg, i.p.) attenuated the elevated plasma glucose induced by oral glucose in normal and type 2 DM (T2DM) mice. Compared to the effect of injected insulin (0.5 IU/kg), borapetoside C caused a more prominent increase of glycogen content in skeletal muscle of T2DM mice, but a less increase in type 1 DM (T1DM) mice. Combined treatment of a low dose borapetoside C (0.1mg/kg, i.p.) plus insulin enhanced insulin-induced lowering of the plasma glucose level and insulin-induced increase of muscle glycogen content. Continuous treatment with 5mg/kg borapetoside C (twice daily) for 7 days increased phosphorylation of insulin receptor (IR) and protein kinase B (Akt) as well as the expression of glucose transporter-2 (GLUT2) in T1DM mice. Combined treatment of a low dose borapetoside C (0.1mg/kg, twice daily) plus insulin for 7 days enhanced insulin-induced IR and Akt phosphorylation and GLUT2 expression in the liver of T1DM mice. This study proved that borapetoside C can increase glucose utilization, delayed the development of insulin resistance and enhanced insulin sensitivity. The activation of IR-Akt-GLUT2 expression and the enhancement of insulin sensitivity may contribute to the hypoglycemic action of borapetoside C in diabetic mice. 相似文献
993.
Qiaoping?Qin Quentin?Kaas Chi?Zhang Luping?Zhou Xiaoyan?Luo Mingbing?Zhou Xiaoming?Sun Lanlan?Zhang Kee-Yoeup?Paek Yongyi?CuiEmail author 《Journal of Plant Growth Regulation》2012,31(2):139-155
Massive flowering of tropical Phalaenopsis orchids is coordinated by the cold-induced release of reproductive bud dormancy. Light and temperature are the two key factors
integrated by the dormancy mechanism to both stop and reactivate the meristem development of many other angiosperm species,
including fruit trees and ornamental plants. It is well established that leaves and roots play a major role in inducing flower
development; however, currently, knowledge of molecular events associated with reproductive bud dormancy release in organs
other than the bud is limited. Using differential gene expression, we have shown that the leaves of a hybrid of Phalaenopsis species, Doritaenopsis ‘Tinny Tender’, undergo major metabolic modifications. These changes result in the production of sucrose and amino acids,
both of which can sustain bud outgrowth, and auxin and ethylene, which may play important roles in awaking the dormant buds.
Intake of abscisic acid and synthesis of the hormone jasmonate may also explain the inhibition of vegetative growth that coincides
with bud growth. Interestingly, many genes that were upregulated by cold treatment are homologous for genes involved in flower
induction and vernalization in Arabidopsis, indicating that processes regulating flowering induction and those regulating reproductive bud dormancy release may use
similar pathways and effector molecules. 相似文献
994.
Roca H Craig MJ Ying C Varsos ZS Czarnieski P Alva AS Hernandez J Fuller D Daignault S Healy PN Pienta KJ 《Journal of cellular biochemistry》2012,113(5):1569-1580
Interleukin (IL)-4 plays a critical role in the regulation of immune responses and has been detected at high levels in the tumor microenvironment of cancer patients where it correlates with the grade of malignancy. The direct effect of IL-4 on cancer cells has been associated with increased cell survival; however, its role in cancer cell proliferation and related mechanisms is still unclear. Here it was shown that in a nutrient-depleted environment, IL-4 induces proliferation in prostate cancer PC3 cells. In these cells, under nutrient-depletion stress, IL-4 activates mitogen-activated protein kinases (MAPKs), including Erk, p38, and JNK. Using MAP-signaling-specific inhibitors, it was shown that IL-4-induced proliferation is mediated by JNK activation. In fact, JNK-inhibitor-V (JNKi-V) stunted IL-4-mediated cell proliferation. Furthermore, it was found that IL-4 induces survivin up-regulation in nutrient-depleted cancer cells. Using survivin-short-hairpin-RNAs (shRNAs), it was demonstrated that in this milieu survivin expression above a threshold limit is critical to the mechanism of IL-4-mediated proliferation. In addition, the significance of survivin up-regulation in a stressed environment was assessed in prostate cancer mouse xenografts. It was found that survivin knockdown decreases tumor progression in correlation with cancer cell proliferation. Furthermore, under nutrient depletion stress, IL -4 could induce proliferation in cancer cells from multiple origins: MDA-MB-231 (breast), A253 (head and neck), and SKOV-3 (ovarian). Overall, these findings suggest that in a tumor microenvironment under stress conditions, IL-4 triggers a simultaneous activation of the JNK-pathway and the up-regulation of survivin turning on a cancer proliferation mechanism. 相似文献
995.
MacEntee MI Mariño R Wong S Kiyak A Minichiello V Chi I Lo EC Huancai L 《Gerodontology》2012,29(2):e822-e832
doi: 10.1111/j.1741‐2358.2011.00568.x Discussions on oral health care among elderly Chinese immigrants in Melbourne and Vancouver Background: This study explored how elderly Chinese immigrants value and relate to how acculturation influences oral health and subsequent service use. Methods: Elders who had immigrated to Melbourne and Vancouver within the previous 15 years were recruited from local community centres and assigned to focus groups of 5–7 participants in Vancouver (4 groups) or Melbourne (5 groups). Results: Following an iterative process of thematic analysis, the discussions revealed that immigrants care about the comfort and appearance of their teeth, and they value Western dentistry as a supplement to traditional remedies, but they have difficulty getting culturally sensitive information about oral health care. Accessing dentistry, they explained, is distressing because of language problems and financial costs that impose on their children. Consequently, many immigrants obtain dental treatment in China when they return for occasional visits. They felt that separation of dentistry from national health care programmes in Canada and Australia disregards natural links between oral health and general health. Conclusions: The similarity of concerns in both cities suggests that dissemination of information and availability of services are the important themes influencing oral health, and that, beliefs developed over a lifetime play an important role in interpreting oral health in the host country. 相似文献
996.
CD Chiang CL Lewis MD Wright S Agapova B Akers TD Azad K Banerjee P Carrera A Chen J Chen X Chi J Chiou J Cooper M Czurylo C Downs SY Ebstein PG Fahey JW Goldman A Grieff S Hsiung R Hu Y Huang A Kapuria K Li I Marcu SH Moore AC Moseley N Nauman KM Ness DM Ngai A Panzer P Peters EY Qin S Sadhu A Sariol A Schellhase MB Schoer M Steinberg G Surick CA Tsai K Underwood A Wang MH Wang VM Wang D Westrich LJ Yockey L Zhang ED Herzog 《Journal of biological rhythms》2012,27(4):333-336
Although chronobiology is of growing interest to scientists, physicians, and the general public, access to recent discoveries and historical perspectives is limited. Wikipedia is an online, user-written encyclopedia that could enhance public access to current understanding in chronobiology. However, Wikipedia is lacking important information and is not universally trusted. Here, 46 students in a university course edited Wikipedia to enhance public access to important discoveries in chronobiology. Students worked for an average of 9 h each to evaluate the primary literature and available Wikipedia information, nominated sites for editing, and, after voting, edited the 15 Wikipedia pages they determined to be highest priorities. This assignment (http://www.nslc.wustl.edu/courses/Bio4030/wikipedia_project.html) was easy to implement, required relatively short time commitments from the professor and students, and had measurable impacts on Wikipedia and the students. Students created 3 new Wikipedia sites, edited 12 additional sites, and cited 347 peer-reviewed articles. The targeted sites all became top hits in online search engines. Because their writing was and will be read by a worldwide audience, students found the experience rewarding. Students reported significantly increased comfort with reading, critiquing, and summarizing primary literature and benefited from seeing their work edited by other scientists and editors of Wikipedia. We conclude that, in a short project, students can assist in making chronobiology widely accessible and learn from the editorial process. 相似文献
997.
998.
999.
Lee SY Kim JH Jung H Chi SW Chung SJ Lee CK Park BC Bae KH Park SG 《Journal of microbiology and biotechnology》2012,22(4):571-573
Glyceraldehyde-3-phosphate (G-3-P), the substrate of glyceraldehyde-3-phosphate dehydrogenase (GAPDH), is a key intermediate in several metabolic pathways. Recently, we reported that G-3-P directly inhibits caspase-3 activity in a reversible noncompetitive mode, suggesting the intracellular G-3-P level as a cell fate decision factor. It has been known that apoptotic stimuli induce the generation of NO, and NO S-nitrosylates GAPDH at the catalytic cysteine residue, which confers GAPDH the ability to bind to Siah-1, an E3 ubiquitin ligase. The GAPDH-Siah-1 complex is translocated into the nucleus and subsequently triggers the apoptotic process. Here, we clearly showed that intracellular G-3-P protects GAPDH from S-nitrosylation at above a certain level, and consequently maintains the cell survival. In case G-3-P drops below a certain level as a result of exposure to specific stimuli, G-3-P cannot inhibit S-nitrosylation of GAPDH anymore, and consequently GAPDH translocates with Siah-1 into the nucleus. Based on these results, we suggest that G-3-P functions as a molecule switch between cell survival and apoptosis by regulating S-nitrosylation of GAPDH. 相似文献
1000.