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131.
Nicotinamide attenuates neuronal cell death related to focal cerebral ischemic injury. This study investigated whether nicotinamide exerts a neuroprotective effect through the activation of Raf- mitogen-activated protein kinase kinase (MEK)-ERK and its downstream targets, including p90 ribosomal S6 kinase (p90RSK) and Bad. Adult male Sprague-Dawley rats were treated with nicotinamide (500 mg/kg) or vehicle 2 hr after the onset of middle cerebral artery occlusion (MCAO). Brains were collected 24 hr after MCAO. In the present study, nicotinamide significantly reduces the volume of infarct regions and decreases the number of positive cells by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining in the cerebral cortex. Nicotinamide prevents injury-induced decrease in Raf-1, MEK1/2, and ERK1/2 phosphorylation. As part of the downstream cascade, nicotinamide inhibits the injury-induced decrease in p90RSK and Bad phosphorylation. Moreover, nicotinamide prevents the injury-induced increase in cleaved caspase-3 levels. These findings suggest that nicotinamide protects neuronal cells against cerebral ischemic injury and that MEK-ERK-p90RSK cascade activation by nicotinamide contributes to these neuroprotective effects.  相似文献   
132.
Y. J. Koh 《Plant pathology》2018,67(5):1208-1219
Bacterial canker of kiwifruit, caused by Pseudomonas syringae pv. actinidiae (Psa), is a severe threat to kiwifruit production in Korea. An existing infection risk model from New Zealand was adopted to respond to this epidemic. Disease incidence (proportion of diseased leaves on each vine) and weather (hourly temperature, rainfall and relative humidity) data required to develop the model were collected and analysed in the study. Disease incidence data were used to modify and validate the existing model. Because the Psa risk model was originally developed in a region where the characteristic climatic conditions are completely different from those in Korea, the temperature and rainfall functions of the existing model were modified. Analyses using statistical correlation and prediction–realization tables revealed that the modified model is valid with high agreement (a correlation coefficient of 0.85 and an accuracy of 85.7%, respectively) between the observed disease incidence and simulated disease risk from the model. The model was also found to be more highly sensitive to the presence or absence of rainfall than any other weather variable inputs. Uncertainty in simulated disease risk was measured based on the level of uncertainty in temperature input from weather forecasts. Overall, these results indicate that the modified Psa risk model can be used to provide practical and applicable information for timely disease control to the kiwifruit growers in Korea.  相似文献   
133.
Antifreeze proteins (AFPs) and glycoproteins (AFGPs), collectively called AF(G)Ps, constitute a diverse class of proteins found in various Arctic and Antarctic fish, as well as in amphibians, plants, and insects. These compounds possess the ability to inhibit the formation of ice and are therefore essential to the survival of many marine teleost fishes that routinely encounter sub-zero temperatures. Owing to this property, AF(G)Ps have potential applications in many areas such as storage of cells or tissues at low temperature, ice slurries for refrigeration systems, and food storage. In contrast to AFGPs, which are composed of repeated tripeptide units (Ala-Ala-Thr)n with minor sequence variations, AFPs possess very different primary, secondary, and tertiary structures. The isolation and purification of AFGPs is laborious, costly, and often results in mixtures, making characterization difficult. Recent structural investigations into the mechanism by which linear and cyclic AFGPs inhibit ice crystallization have led to significant progress toward the synthesis and assessment of several synthetic mimics of AFGPs. This review article will summarize synthetic AFGP mimics as well as current challenges in designing compounds capable of mimicking AFGPs. It will also cover our recent efforts in exploring whether peptoid mimics can serve as structural and functional mimics of native AFGPs.  相似文献   
134.
Estradiol acts as a neuroprotective factor against ischemic brain injury. This study investigated whether estradiol modulates neuroprotective mechanism through the activation of Akt and its downstream target such as Bad in global ischemic injury. Adult female gerbils were ovariectomized and treated with estradiol prior to ischemic injury. Transient cerebral ischemia was accomplished by bilateral clipping of the common carotid artery for 5 min. Brains were collected on 1, 3, 5 day after injury. In hippocampal CA1 region of non-treated gerbils, most of neuronal cells exhibited pyknotic nuclei and showed the positive reaction of TUNEL staining on 5 day after injury. However, estradiol significantly reduced the neuronal cell death. Potential activation was measured by phosphorylation of Akt at Ser473 and Bad at Ser136 using western blot analysis. The levels of pAkt and pBad were significantly decreased in non-treated gerbils on 1-5 day after injury. However, estradiol prevents the global ischemic injury-induced decrease of pAkt and pBad. Our findings suggest that estradiol prevents cell death due to global ischemic injury and that Akt activation and Bad phosphorylation by estradiol mediated these protective effects.  相似文献   
135.
Drinking an herbal tea to lose weight is a well-liked concept. This study was designed to examine the possible improvement of obesity phenotype by a new tea represented by its purified components, gallic acid, ellagic acid, and rubusoside (GER). Male obese-prone SD rats were given low-fat diet, high-fat diet, or high-fat diet plus GER at the dose of 0.22 g/kg of body weight for 9 weeks. GER significantly reduced body weight gain by 22% compared to the high-fat diet control group with 48% less abdominal fat gain. Food intake was not affected. Blood glucose was lowered in the GER-treated group, whereas serum triglycerides and cholesterol were significantly reduced by 50%. This improved obesity phenotype may be associated with the attenuated expression of vascular endothelial growth factor in preadipocyte 3T3-L1 cells. Although other underlying, possibly multiple, mechanisms behind the improved phenotype are largely unknown, the observed improvement of multiple obesity-related parameters by the new tea warrants further investigations.  相似文献   
136.
137.
世界不同地理来源粳稻品种的遗传相似性研究   总被引:10,自引:3,他引:10  
 【目的】探讨不同国家(或地区和组织)间粳稻选育品种的遗传相似性和遗传差异,旨在为世界各地的粳稻品种能够有效利用于水稻育种提供科学依据。【方法】利用34对SSR引物对不同地理来源包括20个国家(或地区和组织)的313份粳稻选育品种进行遗传相似性和聚类分析。【结果】共检测到198个等位基因,平均每对SSR引物检测到的等位基因数为5.8235个。RM320、RM531、RM1、RM21和RM336的等位基因数较多,分别为16、13、12、10和10个;RM320、RM336、RM286、RM531和RM21的遗传多样性指数较高,分别为2.3668、2.0041、1.9684、1.9508和1.7203。各国家(或地区和组织)粳稻选育品种的遗传相似系数变异范围为0.279~0.918,平均值为0.653。纬度和地理位置相近的国家间粳稻品种的遗传相似系数较大,基本聚为同一个类群,而纬度差异较大,地理位置较远的国家间粳稻品种的遗传相似系数较小,聚为不同类群。 【结论】粳稻品种的遗传相似性与纬度和地理位置有着密切的联系。  相似文献   
138.
We investigated the relationship between cartilage oligomeric matrix protein (COMP) levels in synovial fluid (SF), serum and urine and the development of osteochondral damage and osteophyte (OP) formation following intraarticular fractures of the carpus in racehorses in order to assess the clinical usefulness of COMP as a diagnostic biomarker of developmental osteoarthritis (OA). Two monoclonal antibodies (mAb clones 2A11 and 3C8) raised against equine COMP were shown to be capable of detecting the molecule in serum and urine as well as SF. Fifty-one samples were obtained from 26 OP-positive (OP(+)) and 25 OP-negative (OP(-)) racehorses with carpal bone fracture, in whom OP was ascertained arthroscopically and radiographically. The COMP measurements obtained using the two mAbs were highly correlated with each other in SF, serum, or urine. Horses with OP(+) showed a significantly higher [urinary COMP (microg)]/[urinary creatinine (mg)] ratio (4.94 +/- 5.10 and 1.46 +/- 1.19, using mAbs 2A11 and 3C8, respectively) than OP(-) horses (2.80 +/- 1.72 and 0.93 +/- 0.49, respectively). The relationship between serum and urine COMP levels and the period from injury to surgery were extrapolated using a polynomial expression. Measurement of COMP, especially in urine, has potential as a predictive marker of advanced OA following carpal bone fractures in racehorses.  相似文献   
139.
The present study was designed to evaluate whether ethanol suppresses survival-signaling pathways in rat testes. Ethanol (1.5 g/kg or 3 g/kg i.p., 15% v/v in saline) was administrated to adult male rats for 10 days. Ethanol treatment significantly increased the number of TUNEL-positive cells in rat testes. Potential activation was measured by phosphorylation of Akt and Erk1/2 using Western blot analysis. Ethanol decreased the levels of activated survival kinases, pAkt and pErk1/2. The phosphorylation of Bad at Ser112 and Ser136 was decreased in ethanol-treated animals in comparison to saline-treated animals. Moreover, the interaction of pBad with 14-3-3 was decreased by ethanol exposure. In conclusion, our findings suggest that ethanol induces apoptotic cell death by suppressing the activation of survival kinases and the phosphorylation of their downstream targets in rat testes.  相似文献   
140.
Navjot Sodhi and we often discussed how growing global demands for food are placing increasing pressures on tropical forests. Although more consumers are demanding for ‘greener’ products associated with sustainable production, green consumerism and improved production practices per se might not adequately curtail destruction of forests and biodiversity. Instead, we argue that consumers in emerging and developed countries need to avoid wasteful and excessive consumption. We demonstrate how reasonable recalibration of consumer aspirations and changes in consumption levels in China, India, the European Union and United States might substantially alleviate environmental impacts associated with oilseed production in Indonesia, Malaysia, Brazil and Argentina. We do so through a scenario analysis that projects oilseed demands and expansion from current levels to 2100 under three alternative consumption trends. We show that pursuing a business-as-usual course of consumption would impose severe pressures in producer countries to clear land for oil-palm and soybean agriculture (up to an additional ~12 million hectares by 2040), which could exacerbate rates of deforestation and biodiversity loss in these tropical regions. On the other hand, if each person in the EU and US reduces his/her daily vegetable oil consumption by an average of 25 g – roughly equivalent to forgoing one large serving of French Fries – the pressure to convert tropical forests for oilseed expansion could be reduced by up to ~70%. Our analysis demonstrates how changes in consumer behavior in industrialized nations could substantially alleviate environmental impacts associated with agricultural production in the developing tropics.  相似文献   
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