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1.
It is well recognized that the world population is ageing rapidly. Therefore, it is important to understand ageing processes at the cellular and molecular levels to predict the onset of age‐related diseases and prevent them. Recent research has focused on the identification of ageing biomarkers, including those associated with the properties of the Golgi apparatus. In this context, Golgi‐mediated glycosylation of proteins has been well characterized. Additionally, other studies show that the secretion of many compounds, including pro‐inflammatory cytokines and extracellular matrix–degrading enzymes, is modified during ageing, resulting in physical and functional skin degradation. Since the Golgi apparatus is a central organelle of the secretory pathway, we investigated its structural organization in senescent primary human dermal fibroblasts using confocal and electron microscopy. In addition, we monitored the expression of Golgi‐related genes in the same cells. Our data showed a marked alteration in the Golgi morphology during replicative senescence. In contrast to its small and compact structure in non‐senescent cells, the Golgi apparatus exhibited a large and expanded morphology in senescent fibroblasts. Our data also demonstrated that the expression of many genes related to Golgi structural integrity and function was significantly modified in senescent cells, suggesting a relationship between Golgi apparatus function and ageing.  相似文献   
2.
David Marr's three-level method for completely understanding a cognitive system and the importance he attaches to the computational level are so familiar as to scarcely need repeating. Fewer seem to recognize that Marr defends his famous method by criticizing the “reductionistic approach.” This sets up a more interesting relationship between Marr and reductionism than is usually acknowledged. I argue that Marr was correct in his criticism of the reductionists of his time—they were only describing (cellular activity), not explaining (cognitive functions). But a careful metascientific account of reductionistic neuroscience over the past two decades reveals that Marr's criticisms no longer have force. Contemporary neuroscience now explains cognition directly, although in a fashion—causal-mechanistically—quite different than Marr recommended. So while Marr was correct to reject the reductionism of his day and offer an alternative method for genuinely explaining cognition, contemporary cognitive scientists now owe us a new defense of Marr's famous method and the advantages of its explanations over the type now pursued successfully in current reductionist neuroscience. There are familiar reasons for thinking that this debt will not be paid easily.  相似文献   
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The purpose of the work was to set‐up a simple method to evaluate the contribution of Mn2+ ions in the intra‐ and extracellular tumor compartments in a MEMRI experiment. This task has been tackled by “silencing” the relaxation enhancement arising from Mn2+ ions in the extracellular space. In vitro relaxometric measurements allowed assessment of the sequestering activity of DO2A (1,4,7,10‐tetraazacyclododecane‐1,7‐diacetic acid) towards Mn2+ ions, as the addition of Ca‐DO2A to a solution of MnCl2 causes a drop of relaxivity upon the formation of the highly stable and low‐relaxivity Mn‐DO2A. It has been proved that the sequestering ability of DO2A towards Mn2+ ions is also fully effective in the presence of serum albumin. Moreover, it has been shown that Mn‐DO2A does not enter cell membranes, nor does the presence of Ca‐DO2A in the extracellular space prompt migration of Mn ions from the intracellular compartment. On this basis the in vivo, instantaneous, drop in SE% (percent signal enhancement) in T1‐weighted images is taken as evidence of the sequestration of extracellular Mn2+ ions upon addition of Ca‐DO2A. By applying the method to B16F10 tumor bearing mice, T1 decrease is readily detected in the tumor region, whereas a negligible change in SE% is observed in kidneys, liver and muscle. The relaxometric MRI results have been validated by ICP‐MS measurements. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
5.
目的观察不同时点电针对直肠癌开腹手术患者围术期应激反应及免疫功能的影响。方法240例择期行直肠癌根治性开腹手术而住院的患者,随机分为A组、B组、C组、D组,每组60例。A组设为空白对照组,B组于手术前1 d、C组于手术前1 d和麻醉诱导前30 min、D组分别于手术前1 d、麻醉诱导前30 min及手术后1 d行电针。分别于手术前1 d电针前(T1)、麻醉诱导前电针前(T2)、术毕(T3)和手术后1 d电针后(T4)4个时间采集患者空腹外周静脉血,用Sysmex血细胞分析仪对白细胞与中性粒细胞进行计数;ELISA检测急性期C反应蛋白(CRP)与热反应蛋白70(HSP70)以及细胞因子白介素6(IL-6)、干扰素(IFN-g)、白介素4(IL-4)水平,并计算IFN-g与IL-4比值;采用流式细胞仪测定CD4、CD8的细胞含量并计算两者比值。结果HSP70与CRP水平、白细胞数与中性粒细胞数、IL-4与IL-6水平变化趋势均一致,4组T1、T2时间比较,差异无统计学意义(P>0.05);A组与B组T3和T4时间比较,差异无统计学意义(P>0.05);C组、D组T3和T4时间显著低于A组与B组(P<0.05);D组T4时间显著低于C组(P<0.05);4组T2时间与T1时间比较差异无统计学意义(P>0.05),T3时间高于T2时间(P<0.05),T4时间低于T3时间(P<0.05)。IFN-g变化不显著(P>0.05),IFN-g/IL-4、CD4/CD8变化趋势与以上相反。结论电针术前使用对直肠癌患者无显著疗效,但能够减轻术后应激反应和免疫抑制,并且随着电针次数的合理增加疗效更加显著。  相似文献   
6.
OBJECTIVE: It is well documented that cardiopulmonary bypass (CPB) severely impairs cellular immunity. The objective of this study was to investigate the effect of prostaglandin E1 (PGE1) on cellular immunity after CPB. METHODS: Patients who underwent elective cardiac surgery were randomly divided into the PGE1 group (n=12) and the control group (n=12). In the PGE1 group, PGE1 was administered at 20 ng/kg/min from just after the induction of anesthesia to the end of surgery. Peripheral blood mononuclear cells (PBMCs) were taken before anesthesia and on postoperative days 1, 3 and 7 (POD 1, POD 3 and POD 7). Proliferation responses of T cells to phytohemagglutinin (PHA) and pure protein derivative (PPD) antigen were measured as indicators of cellular immunity. RESULTS: PGE1 significantly attenuated the impairment of both PHA and PPD response after cardiac surgery on POD 1 (PHA response, 30 +/- 21% vs. 53 +/- 32%, control vs. PGE, p=0.048; PPD response, 18 +/- 21% vs. 39 +/- 27%, control vs. PGE, p=0.046). The reduced glutathione content of PBMCs in the control group was significantly decreased on POD 1. CONCLUSION: PGE1 attenuated the impairment of cellular immunity after cardiac surgery with CPB by reducing oxidative stress on PBMCs.  相似文献   
7.
马尔尼菲青霉病不同类型病变中免疫反应观察   总被引:2,自引:0,他引:2  
选用2组病变类型不同的6例马尔尼菲青霉病人病变组织,采用免疫组化PAP法,观察病变组织中l8淋巴细胞、巨噬细胞、IgG、IgM、乙等免疫指标。结果发现马尔尼菲青霉病的病变类型取决于机体的免疫功能状态,人体抗马尔尼菲青霉免疫以细胞免疫为主,组织中T细胞的存在对于杀灭真菌、局限病变具有积极意义;体液免疫特别是特异性抗体的出现除具有促进细胞免疫功能外,可能也是脓肿成因之一。  相似文献   
8.
Objective: Considering the growing use of cellular phones and the fast appearance of new phone models, the electromagnetic interference of currently popular cellular phones on electronic medical equipment was tested. Methods: Three Personal Communication System cellular phones were put at different distances from multiple electronic medical devices, the interference effect was observed and the electromagnetic field strength measured with a spectrum analyser. Results: Only two small pieces of equipment, the CO2 airway adapter and the haemoglucostix meter were affected and then only when the phone was in very close proximity. Conclusion: Compared to the results of our study in 1997 testing Global System for Mobile Communication phones, the Personal Communication System phones generated less electromagnetic interference. However a much larger scaled study and an accurate international electromagnetic interference standard are recommended before any change in the current restrictive hospital policy on mobile phone usage could be recommended.  相似文献   
9.
拆方研究补中益气汤中黄芪 甘草及全方的免疫调节作用   总被引:11,自引:0,他引:11  
目的 检测补中益气汤中黄芪、甘草及全方对病态机体的免疫调节作用。方法 分 7组检测全方中黄芪、甘草及全方缺黄芪、缺甘草组方对利血平制备的脾虚小鼠的 5项非特异性免疫功能的影响进行研究。结果 黄芪能使Hb明显升高 ,单味甘草对某些免疫功能不起作用甚至起抑制作用 ,缺甘草组方作用低于全方 ,全方能明显提高机体免疫功能。结论 黄芪是方中主要升高Hb药物 ;方中甘草起到特殊的调节作用。  相似文献   
10.
Copper (Cu)-dependent lysyl oxidase (LO) catalyzes crosslinking of collagen and elastin stabilizing the extracellular matrix (ECM). Chronic inhalation of cadmium (Cd), a toxic metal, induces emphysema. To probe mechanisms of Cd injury to the lung, we developed Cd-resistant (CdR) cells from rat fetal lung fibroblasts (RFL6) by chronic exposure to CdCl(2) from 1 to 40 microM and further examined their expressions of LO, LO substrates, and Cu-scavenging thiols. Levels of cellular thiols, metallothionein, and glutathione in CdR cells were elevated to 13.0- and 3.2-fold of parental controls, respectively, whereas LO mRNA and protein levels were markedly reduced in these cells, with catalytic activity declining to only 16% of the parental control. A conspicuous 52 kDa species rather then the normal 50 kDa proenzyme appeared in the CdR cell extract but not in the conditioned medium, which was codistributed with the endoplasmic reticulum marker [DiOC5(3)] within the cell, implying the Cd-induced 52 kDa species as a product of an abnormal LO-processing defect in secretion. Addition of Cu into CdR cell cultures enhanced the expression of LO mRNA, protein and catalytic activities reflecting limitation of Cu bioavailability for LO in these cells. With inhibition of LO, CdR cells also displayed downregulation of collagen and elastin, substrates of LO. Restoration of collagen synthesis by exposure of CdR cells to purified LO or Cu suggests that inhibition of LO and limitation of Cu cofactor by Cd, as key phenotype changes, accelerated collagen and elastin damage, a critical event pertinent to emphysema pathogenesis.  相似文献   
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