自噬对巨噬细胞极化的影响及其与慢性炎症性疾病的关系

自噬是广泛存在于真核细胞内的一种高度保守的细胞过程,它通过降解细胞内受损的细胞器、长寿蛋白、脂质以及病原体,在维持细胞能量稳态、细胞分化及器官发育、炎症及免疫调节方面发挥着重要的作用。细胞在遭受能量应激、缺氧、活性氧释放、DNA损伤、病原体入侵等刺激后会激活自噬相关蛋白及通路,诱导具有双层膜结构的自噬小体形成,自噬小体包裹异常胞内成分后与溶酶体融合,最终降解成为可供细胞循环利用的小分子物。     

自噬:肾脏疾病治疗新靶点

自噬是一种高度保守的细胞行为,是细胞降解自身受损细胞器及大分子物质的过程。该机制广泛存在于所有真核细胞内,细胞稳态因其存在而得以维持。过去的几十年中,国内外关于自噬的研究颇多。多个研究报道了自噬在哺乳动物不同器官中的生理作用以及自噬激活受损在老年病、异常糖脂代谢、神经退行性病变等一系列病理变化中的作用。目前,旨在调节自噬激活的新疗法受到期待。最近几年里,自噬在肾脏中的作用逐渐为人们所关注,一系列研究表明,自噬与多种肾脏疾病相关。现就自噬的分子机制,肾脏自噬相关研究的新进展以及有待解决的问题作一综述。     

自噬在肾癌发生发展与预测中的研究进展

1自噬概述 自噬是一种高度保守的分解代谢多阶段过程,涉及溶酶体对细胞质大分子的降解.在这个过程中,错误折叠的蛋白质和受损的细胞器从细胞质中分离出来,形成称为自噬体的双膜囊泡,并被转移到溶酶体进行消化.然后将消化的细胞成分释放到细胞质中以供再利用[1].因此,自噬在维持细胞内环境稳态和保护细胞免受损伤方面发挥着重要作用....     

自噬与肾小球疾病关系的研究进展

<正>自噬是真核细胞内降解受损细胞器和大分子蛋白质的生理过程。在生理条件下,它可以通过降解细胞器等物质来维持细胞内稳态;相反,在氧化应激等病理条件下自噬活动的变化既可能延缓疾病进展也可能加速疾病进展。近年来越来越多的研究发现自噬参与肾小球疾病的病理生理过程,自噬可能成为肾小球疾病治疗的靶点,本文就自噬与肾小球疾病关系的进展作一综述。     

自噬对肿瘤形成的双重调节作用及相关机制

自噬是溶酶体参与的降解细胞代谢物质、细胞质蛋白质和细胞器的主要途径。自噬是一个多步骤的过程,受损的细胞器或细胞质蛋白质被包裹进单独的膜结构内,并逐步成熟为双层膜小泡即自噬泡。自噬泡与溶酶体融合后形成自噬溶酶体,降解其所包裹的内容物。在正常细胞中,低水平的自噬是细胞应激情况下(如营养物质缺乏、DNA损伤、细胞器损伤等)时所必需的。低水平的细胞自噬还能够帮助降解损伤的细胞器,因而是一种细胞保护机制,但高水平的自     

自噬与2型糖尿病关系研究进展

2型糖尿病是一种以胰岛素抵抗及胰岛β细胞功能紊乱为特点的疾病。自噬在维持β细胞的结构和功能上起重要作用。自噬是一种细胞内的分解代谢过程,是维持体内平衡及内环境稳定的重要机制。在胰岛素抵抗状态下,胰岛β细胞可通过自噬途径降解细胞器及异常聚集的蛋白,减少细胞死亡,从而抑制糖尿病的发生。本文就自噬及其在2型糖尿病状态下对β细胞影响的研究进展作一综述。     

急性胰腺炎自噬受损与细胞器相互作用的研究进展

急性胰腺炎发病机制多样，具体机制尚未阐明。细胞器是散布在细胞质内具有一定形态和功能的微结构或微器官，在胰腺腺泡细胞功能的正常运转中起重要作用。细胞器参与自噬过程，自噬促进细胞器的更新，二者相互协调维持细胞状态的稳定。细胞器及自噬受损参与急性胰腺炎的发生、发展。本文就急性胰腺炎中自噬与细胞器的相互作用、自噬受损在急性胰腺炎发生中作用的研究进展作一综述。     

基于“瘀阻经络”病机探讨自噬与脊髓损伤修复的关系北大核心CSCD

脊髓损伤是各种创伤所致的中枢神经系统损伤的一种疾病。研究发现脊髓损伤后自噬水平一定程度的上调能促进脊髓损伤后功能的修复。自噬在应激状态下通过降解体内过多的错误折叠蛋白及受损细胞器,为细胞供能,以维持细胞内环境的稳定。具有活血祛瘀通络功效的中药在治疗脊髓损伤中广泛受到关注,其作用与细胞自噬的调节有着密切的联系。     

基于“瘀阻经络”病机探讨自噬与脊髓损伤修复的关系

脊髓损伤是各种创伤所致的中枢神经系统损伤的一种疾病。研究发现脊髓损伤后自噬水平一定程度的上调能促进脊髓损伤后功能的修复。自噬在应激状态下通过降解体内过多的错误折叠蛋白及受损细胞器,为细胞供能,以维持细胞内环境的稳定。具有活血祛瘀通络功效的中药在治疗脊髓损伤中广泛受到关注,其作用与细胞自噬的调节有着密切的联系。     

自噬对慢性髓系白血病的双重作用

自噬是溶酶体介导的,以降解和清除衰老的细胞器及错误折叠蛋白质为主,并产生游离氨基酸、脂肪酸供细胞循环利用,以维持细胞内环境稳定的自降解过程。自噬与慢性髓系白血病(chronic myeloid leukemia,CML)的发生、治疗、耐药、复发等方面密切相关。自噬是一把双刃剑,对CML具有诱导细胞死亡和促进细胞存活双重作用。明确不同治疗条件下自噬对CML的不同作用,探索不同的自噬途径,有针对性联合自噬诱导剂或自噬抑制剂,对于提高疗效,克服耐药和复发,促进CML的治愈具有重要意义。本文就自噬对慢性髓系白血病的双重作用做一综述。     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

Guns and Knives in New Mexico: Patterns of Penetrating Trauma, 1978–1993

Objective: To identify patterns of nonfatal and fatal penetrating trauma among children and adults in New Mexico using ED and medical examiner data.
Methods: The authors retrospectively sampled in 5-year intervals all victims of penetrating trauma who presented to either the state Level-1 trauma center or the state medical examiner from a 16-year period (1978–1993). Rates of nonfatal and fatal firearm and stabbing injury were compared for children and adults.
Results: Rates of nonfatal injury were similar (firearm, 34.3 per 100,000 person-years; stabbing, 35.1). However, rates of fatal injury were significantly different (firearm, 21.9; stabbing, 2.7; relative risk: 8.2; 95% confidence interval: 5.4, 12.5). From 1978 to 1993, nonfatal injury rates increased for children (p = 0.0043) and adults (p < 0.0001), while fatal penetrating injury remained constant. The increase in nonfatal injury in children resulted from increased firearm injury rates. In adults, both stabbing and firearm nonfatal injury rates increased.
Conclusions: Nonfatal injury data suggest that nonfatal violence has increased; fatal injury data suggest that violent death rates have remained constant. Injury patterns vary by age, mechanism of trauma, and data source. These results suggest that ED and medical examiner data differ and that both are needed to guide injury prevention programs.