动脉粥样硬化斑块内血管新生的研究进展

动脉粥样硬化是诱导心脑血管相关疾病发生的主要原因,在动脉粥样硬化的影响因素中,血管新生是导致斑块内破裂并引发各种并发症的主要原因之一。缺氧、炎症、生长因子相关因素可引发斑块内血管新生,导致动脉粥样硬化的发生。本文对影响血管新生的相关因素及其作用机制作一综述,为动脉粥样硬化的防治提供新的思路和干预靶点。     

高胰岛素血症对平滑肌细胞基因异常甲基化的作用研究进展

调查发现70％的2型糖尿病患者合并动脉粥样硬化,进一步实验证实胰岛素导致血管平滑肌细胞表型转化是导致动脉粥样硬化发生的重要原因之一.平滑肌细胞表型转化已被证实与基因异常甲基化有关,最近发现高胰岛素可以导致平滑肌细胞基因异常甲基化,由此提出假设,血液中高浓度胰岛素可导致血管平滑肌细胞表型转化,最终导致动脉粥样硬化的发生.     

DNA甲基化及其与动脉粥样硬化的关系

流行病学调查结果表明冠心病有明显的遗传倾向,其发病具有明显的家族聚集性。动脉粥样硬化是导致冠心病的主要因素,DNA甲基化是表观遗传学重要组成部分,调节特异性基因的表达,引起动脉粥样硬化,从而导致冠心病的发生。该文介绍了DNA甲基化及其在动脉粥样硬化的发生、发展方面的相关作用机制。     

血管平滑肌细胞自噬与糖尿病动脉粥样硬化关系的研究进展

动脉粥样硬化是心血管疾病的常见病理表现。糖尿病与动脉粥样硬化发生密切相关,高血糖可通过多种机制导致动脉粥样硬化的发生。自噬是生物进化过程中高度保守的,与生长、发育、衰老、疾病状态等密切相关的生理活动,与动脉粥样硬化等多种心、脑血管疾病的发生、发展密切相关。血管平滑肌细胞自噬在动脉粥样硬化不同阶段起着不同的作用,探究血管平滑肌细胞自噬与糖尿病动脉粥样硬化的关系有望为糖尿病动脉粥样硬化的治疗提供新的方向。     

代谢重编程:单核/巨噬细胞训练免疫参与动脉粥样硬化的新机制

动脉粥样硬化是血管的慢性炎症性疾病,单核/巨噬细胞的异常活化与动脉粥样硬化的发生发展密切相关。近期研究发现单核/巨噬细胞可以通过训练免疫发生代谢重编程,促进炎症反应,加快动脉粥样硬化的进展,并可以导致心血管意外事件的发生。文章综述了单核/巨噬细胞代谢重编程在训练免疫发生中的作用和机制,可能为动脉粥样硬化的防治提供新的治疗靶点和方法。     

DNA甲基化在动脉粥样硬化进程中的作用

动脉粥样硬化是一种基因和环境共同作用导致的复杂疾病,DNA甲基化是一种重要的表观遗传修饰调控机制,由环境因素导致,并可通过有丝分裂遗传下去。目前已有研究表明,DNA甲基化在动脉粥样硬化疾病的发生发展过程中起到至关重要的作用。本文综述了DNA甲基化在动脉粥样硬化方面的研究进展。     

microRNA调节细胞自噬影响动脉粥样硬化

动脉粥样硬化(As)是心脑血管疾病主要的病理因素。关于动脉粥样硬化发生发展的病理机制迄今为止尚未完全阐明。自噬是一种普遍存在于真核细胞中高度保守的生物学过程。正常水平的自噬抑制动脉粥样硬化的发生发展,而自噬缺陷或自噬过度则会加速斑块的破裂,导致心脑血管意外的发生。研究表明,microRNA通过参与动脉粥样硬化相关细胞自噬的调节影响动脉粥样硬化进程。文章主要就microRNA调节内皮细胞、巨噬细胞、平滑肌细胞自噬水平在动脉粥样硬化中的作用进行综述。     

炎症与冠心病关系的研究进展

传统观点认为粥样硬化是与年龄相关的血管的老化过程。然而 ,在 2 0世纪 70年代 ,一些证据提示动脉粥样硬化是血管对损伤的一种生化反应过程[1] 。最近 ,Ross等[2 ] 提出粥样硬化是由于血管损伤 ,继以炎性 -纤维增生反应 ,导致动脉粥样硬化发生。在这个过程中 ,大量的生长因子、细胞素以及调节血管的分子微粒共同参与了动脉粥样硬化的发生。现就炎症与动脉粥样硬化、急性冠状动脉综合征的研究进展综述如下。1　炎症与动脉粥样硬化发生的关系血管、心脏对损伤的应答反应产生炎症。血管损伤导致炎症 ,进而促进了动脉粥样硬化及冠状动脉疾病的…     

冠状血管的解剖意义及动脉粥样硬化的治疗

动脉粥样硬化是心血管疾病导致死亡的最主要原因之一,但其发病原因还没有完全清楚,其防治方法有限。冠状血管是最容易发生动脉粥样硬化的血管,其相应的解剖也有特殊意义,本文就冠状血管的解剖、动脉粥样硬化的靶向治疗及动脉粥样硬化并发症的治疗进行述评。     

树突状细胞在动脉粥样硬化发生发展中的作用

动脉粥样硬化是一种通过内皮细胞触发和持久炎症的慢性疾病。最近研究显示树突状细胞在动脉粥样硬化形成过程中起重要的作用。树突状细胞是与动脉粥样硬化发生发展有关的有效抗原递呈细胞和免疫调节细胞。氧化型低密度脂蛋白、缺氧、尼古丁和热休克蛋白等可导致内皮功能失调,从而影响树突状细胞的黏附和成熟。大量证据证明炎性/免疫活性斑块是导致急性冠状综合征的主要原因之一。在动脉粥样硬化斑块中含有大量的树突状细胞和T淋巴细胞。他汀类药物和地尔硫卓能抑制树突状细胞刺激T细胞反应,从而防止动脉粥样硬化的发生发展。     

Near-neutrality in evolution of genes and gene regulation

The nearly neutral theory contends that the interaction of drift and selection is important and occurs at various levels, including synonymous and nonsynonymous substitutions in protein coding regions and sequence turnover of regulatory elements. Recent progress of the theory is reviewed, and the interaction between drift and selection is suggested to differ at these different levels. Weak selective force on synonymous changes is stable, whereas its consequence on nonsynonymous changes depends on environmental factors. Selection on differentiation of regulatory elements is even more dependent on environmental factors than on amino acid changes. Of particular significance is the role of drift in the evolution of gene regulation that directly participates in morphological evolution. The range of near neutrality depends on the effective size of the population that is influenced by selected linked loci. In addition to the effective population size, molecular chaperones such as heat shock protein 90 have significant effects on the range of near neutrality.     

人群脉压分布特征的研究

目的：探讨脉压（PP）在人群的分布特征。方法：采用1997年北京城市、农村自然人群高血压普查资料（35－74岁）,共29707人,分析PP在人群不同性别、不同年龄组、不同血压水平、不同类型脑卒中分布频率（％）。结果：（1）随着血压的增高PP的分布频率也在增高,血压正常人群,PP在40－49mmHg(1mmHg=0.133kPa)频率最高,在血压I期人群中频率最高的PP在60－69mmHg,在血压Ⅱ期人群中PP70－79mmHg分布频率最高,在血压Ⅲ期人群中频率最高的PP在90－99mmHg;（2）人群缺血性卒中PP高于出血性卒中PP。（3）农村人群高血压患病年龄早于城市4．3－6．4岁,城乡人群发病年龄有显性差异（P＝0．0000）;农村人群高血压患病率明显高于城市（P＝0．0000）;农村人群平均收缩压和舒张压显高于城市（P＝0．0000）。结论：PP增宽是动脉硬化及心血管病高危的一个标志。     

Fundamental bases of digital information processing in nuclear cardiology (III)

This article describes the transformation of the gamma-camera images into digital form. The incidence of a gamma photon on the detector, produces two voltage pulses, which are proportional to the coordinates of the incidence points, and a digital pulse, indicative of the occurrence of the event. The coordinate pulses passes through a analog-digital converter, that is activated by the pulse. The result is the appearance of a digital number at the out-put of the converter, which is proportional to the voltage at its in-put. This number, is stored on the accumulation memory of the system, either on a list mode or on a matrix mode. Static images can be stored on a single matrix. Dynamic data can be stored on a series of matrixes, each representing a different period of acquisition. It is also possible to capture information on a series of matrixes syncronized with the electrocardiogram of the patient. In this instance, each matrix represents a distinct period of the cardiac cycle. Data stored on the memory, can be used to process and display images and quantitative histograms on a video screen. In order to do that, it is necessary to translate the digital data on the memory to voltage levels, and to transform these on light levels on the screen. This, is achieved through a digital analog converter. The reading of the digital memory must be syncronic with the electronic scanning of the video screen.     

The health impact of tourism on local and indigenous populations in resource-poor countries

In the vast Travel Health literature there is still a considerable dearth on tourism's impact on local communities. This review attempts to remedy the situation. Its focus is on potential health impacts on populations living at tourist destinations outside the industrialised world. To facilitate a better understanding of how health is linked to tourism today, a brief overview of the historical and theoretical evolution of tourism is presented. Ecotourism is given special attention as it is perceived as a version of the industry that is more benign on environment and people. After discussing Indigenous Tourism, a variety of potential health implications is outlined. These follow a previously suggested classification of indirect and direct impacts, with the indirect impacts being based on economic, environmental, socio-cultural and, more recently, political impacts, and the direct impacts originating from immediate encounters between tourism and people. Finally, the urgent need for more research is highlighted, and some solutions to minimize health impact are suggested.     

Impact of obesity on exercise performance and pulmonary rehabilitation

While the impact of obesity on respiratory function has been extensively studied, and several definitive conclusions have emerged, its impact on exercise performance is complex, with the available data sometimes providing contradictory or inconclusive information. Based on the literature discussed, it appears that resting alterations in lung volumes and gas exchange become attenuated during exercise in the obese, while oxygen cost of breathing and dyspnoea are increased. Respiratory muscle function also seems to be impaired, such that inspiratory muscle strength is reduced and respiratory drive is increased. Furthermore, while there is no reduction in the absolute values of maximal oxygen uptake compared with normal-weight subjects, oxygen uptake at a given workload is increased and maximal workload is reduced in the obese, caused by increases in body mass and/or basal metabolic rate. To date, obesity has not been listed as an indication for pulmonary rehabilitation (PR), hence the reason why conclusive data on the impact of obesity per se on PR are lacking. The majority of evidence discussed is based on comparative data from obese versus normal-weight patients, with respiratory disorders currently established as indications for PR. The best evidence currently available regarding the impact of obesity on PR is for patients with chronic obstructive pulmonary disease (COPD); here, it appears that obesity per se has no negative impact on PR. Otherwise, there are no conclusive data on the impact of obesity on PR in respiratory disorders other than COPD, and this remains to be investigated in the future.     

104例非霍奇金淋巴瘤诊断回顾分析

目的 总结现今非霍奇金淋巴瘤确诊途径和方法及病理类型.方法 回顾我院1995～2006年104例非霍奇金淋巴瘤诊断方法和临床主要症状,并对其病理诊断类型加以总结.结果 104例淋巴瘤患者结内发病62例,其中颈部,锁骨上淋巴结确诊50例.结外发病42例,其中皮疹和皮下结节活检确诊9例,脾切除确诊9例,胃镜活检确诊6例,骨髓形态学诊断6例.病理分型弥漫大B细胞淋巴瘤占32例,外周T细胞淋巴瘤15例,滤泡型12例,MALT 8例.结论 颈部和锁骨上淋巴结活检是确诊淋巴瘤的主要途径,但由于淋巴瘤的结外发病,使其诊断相当困难,组织活检是确诊的金指标.病理类型诊断非常重要,其中弥漫大B细胞淋巴瘤是NHL的主要类型.     

Different role of CD73 in leukocyte trafficking via blood and lymph vessels

CD73 is involved in the extracellular ATP metabolism by dephosphorylating extracellular AMP to adenosine and thus regulating permeability of the blood vessels and leukocyte traffic into the tissues. It is also present on lymphatic vessels where its distribution and function have not been characterized. We found that CD73 is expressed on a subpopulation of afferent lymph vessels but is absent on efferent lymphatics, unlike LYVE-1 and podoplanin, which are expressed on both types of lymphatics. The extracellular nucleotide metabolism on lymphatic endothelium differs from that on blood vessel endothelium as lymphatic endothelium has lower NTPDase and higher ecto-5'-nucleotidase/CD73 activity than blood vascular endothelium. In knockout mice, the lack of CD73 on lymphocytes decreases migration of lymphocytes to the draining lymph nodes more than 50% while CD73-deficient lymph vessels mediate lymphocyte trafficking as efficiently as the wild-type lymphatics. Thus, although endothelial CD73 is important for permeability and leukocyte extravasation in blood vessels, it does not have a role in these functions on lymphatics. Instead, lymphocyte CD73 is intimately involved in lymphocyte migration via afferent lymphatic vessels.     

Study of 20 cases of apparently primary pulmonary arterial hypertension]

The authors have studied the clinical, electrocardiographic, radiological, phonomechanographic and haemodynamic features of 20 cases of apparently primary pulmonary hypertension of fairly severe degree. An attempt has been made to correlate on the one hand the haemodynamic values, and on the other the clinical findings, ECG signs of right-sided preponderance, the size of the artery to the right lower lobe on X ray, and the phonomechanographic results. Particular importance is given to a discussion on the aetiology. It is recalled that syphilis can be excluded, that it is possible the operate on thromboses, and that bilharzia and the haemoglobinopathies may play a part which is yet to be defined.     

Heart surgery in the elderly]

The literature of the last five years is reviewd to evaluate the mortality and morbidity of the cardiac surgery (valve replacement and aorto-coronary by-pass, single or combined) in comparison with other patients. There is some slight increase in mortality and morbidity of these patients, depending on of non cardiac causes. Cardiac surgery can improve the quality of live and increase life expectancy of these patients, but the results are influenced by age. On the surgery of valve replacement is important to avoid the funcional deterioration, because the mortality on classe IV is very high. The results of aorto-coronary by-pass on the elderly are not influenced by the coronary anatomy on these ages. The mortality is slightly increased on the majority of the published results. Urgent surgery has a very high mortality on theses ages. The perfection of the surgical techniques and a carefull post-operative care are essencial factors for a good result.     

Magnetic resonance venography of the lower limb.

Prior to surgery or endovascular therapy for the lower extremity varicose veins or deep venous thrombosis (DVT), ultrasonography provides useful information. But it depends on the operator's technique, each image is limited to a small field of view and interpretation may be subjective. On the other hand, magnetic resonance (MR) imaging is now available with several postprocessing techniques using workstations to demonstrate the gross and objective morphology of these lesions less invasively than the conventional ascending venography. As non-contrast MR venography, fat suppressed three-dimensional (3D) coronal balanced turbo field echo (bTFE) is mainly applied in the semisupine position. The varicose veins on the muscle fascia are easily recognized on volume rendering and the perforating veins can be identified on maximum intensity projection (MIP) and axial multiplanar reconstructions. Gadolinium-enhanced fluid attenuated inversion recovery-bTFE is added when coexisting joint effusion or edema masks the veins. For DVT, direct thrombus imaging (DTI) using fat suppressed 3D coronal inversion recovery-prepared blood suppressed gradient echo sequence is applied. However, the signal intensity of DVT depends on the clot's age on DTI and is sometimes confusing on bTFE. After gadolinium administration, blood shows higher signal intensity than clots regardless of the age and DVT can be easily depicted as filling defects on the axial reformations and summarized on the soap bubble-MIP.