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71.
Adenosine monophosphate (AMP)-activated protein kinase (AMPK) plays a key role in maintaining cellular metabolism. AMP or adenosine diphosphate (ADP) levels rise during metabolic stress, such as during nutrient starvation, hypoxia and muscle contraction, and bind to AMPK to induce activity. Recently, activation of AMPK has been considered an attractive therapeutic strategy in the field of human oncology. Structural optimization of lead compound 2, a new type of AMPK activator with potent AMPK activation activity and attractive selective growth inhibition against human cancer cells, improved aqueous solubility, metabolic stability and animal pharmacokinetics (PK) and culminated in the identification of (5-{1-[(6-methoxypyridin-3-yl)methyl]piperidin-4-yl}-1H-benzimidazol-2-yl)(4-{[4-(trifluoromethyl)phenyl]methyl}piperazin-1-yl)methanone ditosylate, ASP4132 (28). Studies on ASP4132 had advanced to clinical trials for the treatment of cancer.  相似文献   
72.
Ischaemic disorders are leading causes of morbidity and mortality worldwide. While the current therapeutic approaches have improved life expectancy and quality of life, they are unable to “cure” ischemic diseases and instate regeneration of damaged tissues. Exosomes are a class of extracellular vesicles with an average size of 100–150 nm, secreted by many cell types and considered a potent factor of cells for paracrine effects. Since exosomes contain multiple bioactive components such as growth factors, molecular intermediates of different intracellular pathways, microRNAs and nucleic acids, they are considered as cell-free therapeutics. Besides, exosomes do not rise cell therapy concerns such as teratoma formation, alloreactivity and thrombotic events. In addition, exosomes are stored and utilized more convenient. Interestingly, exosomes could be an ideal complementary therapeutic tool for ischemic disorders. In this review, we discussed therapeutic functions of exosomes in ischemic disorders including angiogenesis induction through various mechanisms with specific attention to vascular endothelial growth factor pathway. Furthermore, different delivery routes of exosomes and different modification strategies including cell preconditioning, gene modification and bioconjugation, were highlighted. Finally, pre-clinical and clinical investigations in which exosomes were used were discussed.  相似文献   
73.
随着越来越多生物基因组测序的完成,生物医学研究已进入后基因组时代。基因捕获技术由于其在克隆、发现新基因及揭示基因功能方面具有独特的优点,已成为功能基因组时代研究的有力工具,在生物医学研究各个领域的应用日趋广泛。主要对基因捕获技术的原理、分类、一般操作流程、优缺点及基因捕获在发育生物学、新基因鉴定、干细胞分化、肿瘤和生殖医学研究方面的应用作一综述,为相关研究者提供借鉴。  相似文献   
74.

Background

Numerous studies have reported on the healing powers of plants and nature, but there have not been so many instances of experimental research. In particular, there are very few psychological and physiological studies using tactile stimuli. This study examines the psychological and physiological effects of touching plant foliage by using an evaluation profile of the subjects’ impressions and investigating cerebral blood flow.

Methods

The subjects were 14 young Japanese men aged from 21 to 27 years (mean ± standard deviation: 23.6 ± 2.4). With their eyes closed, the subjects touched four different tactile samples including a leaf of natural pothos (Epipremnum aureum). The physiological indices were compared before and after each stimulus. Psychological indices were obtained using a ‘semantic differential’ method.

Results

The fabric stimulus gave people ‘soft’ and ‘rough’ impressions, ‘kind’, ‘peaceful’ and ‘pleasant’ feelings psychologically, and a sense of physiological calm. On the other hand, the metal stimulus gave people ‘cold’, ‘smooth’ and ‘hard’ impressions and an image of something ‘artificial’. The metal stimulus caused a stress response in human cerebral blood flow although its evaluation in terms of ‘pleasant or unpleasant’ was neutral. There were no remarkable differences between the stimuli of natural and artificial pothos compared with other types of stimulus psychologically. However, only the natural pothos stimulus showed a sense of physiological calm in the same appearance as the fabric stimulus.

Conclusions

This study shows that people experience an unconscious calming reaction to touching a plant. It is to be concluded that plants are an indispensable element of the human environment.  相似文献   
75.
目的:研究药剂科积极参与下中西药联合使用对消化内科患者用药合理性的影响。方法:选取我院2014年1月至2015年12月收治且确诊为消化性疾病患者184例,通过随机数表法将患者平均分为对照组和实验组,对照组给予临床常规中西药联合治疗,观察并统计临床反应;实验组给予中西药联合治疗,由本院药剂科参与人员、临床医师联合管理。统计并分析两组疗效、用药合理性及不良反应。结果:对照组总有效率为82.60%,明显低于实验组的94.56%(X~2=5.944,p=0.015);对照组用药合理率为77.17%,明显低于实验组的89.13%(X~2=5.102,p=0.024);对照组不良反应合理率为61.96%,明显低于实验组的88.04%(X~2=18.026,p0.001)。结论:药剂科的积极参与提高了中西药联合使用对消化内科患者的疗效,也降低了不良反应的发生率。  相似文献   
76.
Using mouse peritoneal macrophages, we have examined the mechanism by which, Smilacis rhizoma (SR) regulates nitric oxide (NO) production. When SR was used in combination with recombinant interferon-gamma (rIFN-gamma), there was a marked cooperative induction of NO production. However, SR had no effect on NO production by itself. The increased production of NO from rIFN-gamma plus SR-stimulated cells was almost completely inhibited by pre-treatment with pyrrolidine dithiocarbamate (PDTC), an inhibitor of nuclear factor kappa B (NF-kappaB). Furthermore, treatment of peritoneal macrophages with rIFN-gamma plus SR caused a significant increase in tumor necrosis factor-alpha (TNF-alpha) production. PDTC also decreased the effect of SR on TNF-alpha production significantly. These findings demonstrate that SR increases the production of NO and TNF-alpha by rIFN-gamma-primed macrophages and suggest that NF-kappaB plays a critical role in mediating these effects of SR.  相似文献   
77.
Medicine employs an approach to diagnose, give a prognosis, and develop a treatment for human patients. Specific signs and symptoms determined from medical examinations, laboratory tests, and patient history are utilized to predict the outcome of a potential pathological disorder. Utilizing a strategy similar to the medical examination, the status of ecosystems can be examined. To demonstrate this concept a “patient” case study of the Gulf of Mexico is described. The diagnosis of potential abnormalities within the Gulf of Mexico was conducted by examining field indicators including sediment chemistry and tissue chemistry (field examinations), sediment toxicity (laboratory testing), and a benthic index (patient history and existing symptoms). Based on the diagnosis (ecological assessment), a prognosis for the Gulf of Mexico was determined and specific areas that are impacted by stressors were identified for more detailed assessments. Pensacola Bay was identified as such an area impacted by stressors. The case study example demonstrates that a medical approach of “diagnosis and prognosis” can be utilized as a strategy to help identify stressors, develop a successful treatment plan, and prevent future ecosystem degradation.  相似文献   
78.
Preclinical and clinical investigations have shown the involvement of dysregulation of hypothalamic–pituitary–adrenal (HPA) axis in the pathogenesis of depression. Hypercortisolemia and the associated hippocampal atrophy were observed in patients with depression, which could be ameliorated by the treatment with antidepressants. Therefore, neuroprotection has been proposed to be one of the acting mechanisms of antidepressant. Previous studies in our laboratory have demonstrated the antidepressant-like activity of total glycosides of peony (TGP) in mice. This study aimed to examine the effect of TGP treatment on corticosterone-induced neurotoxicity in cultured rat pheochromocytoma (PC12) cells. Treating the cells with corticosterone at 200 μM for 48 h caused apoptotic cell death. The cytotoxicity was associated with the activation of caspase-3 activity and the decrease in the mRNA ratio of bcl-2 to bax. TPG treatment at increasing doses (1–10 mg/l) protected against the corticosterone-induced toxicity in PC12 cells in a dose-dependent manner. The cytoprotection afforded by TGP treatment was associated with the inhibition of caspase-3 activity and the up-regulation of bcl-2/bax mRNA ratio. The anti-apoptotic effect of TGP is therefore likely mediated by the suppression of the mitochondrial pathway leading to apoptosis.  相似文献   
79.
牛蒡群落分布、物种组成与生态环境因子的关系   总被引:1,自引:0,他引:1  
综合运用相关分析、CCA排序和TWINSPAN分类方法,研究了牛蒡群落分布、物种组成和生态环境因子之间的关系。结果表明:牛蒡群落中牛蒡重要值与各生态环境因子之间没有显著的相关性,证明牛蒡是广布种;牛蒡群落中,除牛蒡外的其他伴生物种的分布与空气相对湿度、年降水量、年均温、海拔高度呈正相关,与土壤有机质含量、日照时数呈负相关;根据牛蒡群落的分类和排序,划分出牛蒡的4大主产区:东北、西北、西南和东南沿海产区,与药典记载的牛蒡的主产区基本一致。  相似文献   
80.
Induced pluripotent stem cells(iPSCs) were first generated by Yamanaka and colleagues over a decade ago. Since then, iPSCs have been successfully differentiated into many distinct cell types, enabling tissue-, disease-, and patientspecific in vitro modelling. Cardiovascular disease is the greatest cause of mortality worldwide but encompasses rarer disorders of conduction and myocardial function for which a cellular model of study is ideal. Although methods to differentiate iPSCs into beating cardiomyocytes(iPSC-CMs) have recently been adequately optimized and commercialized, the resulting cells remain largely immature with regards to their structure and function,demonstrating fetal gene expression, disorganized morphology, reliance on predominantly glycolytic metabolism and contractile characteristics that differ from those of adult cardiomyocytes. As such, disease modelling using iPSC-CMs may be inaccurate and of limited utility. However, this limitation is widely recognized, and numerous groups have made substantial progress in addressing this problem. This review highlights successful methods that have been developed for the maturation of human iPSC-CMs using small molecules,environmental manipulation and 3-dimensional(3 D) growth approaches.  相似文献   
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