L-精氨酸抑制内皮细胞粘附分子-1表达与氧化型低密度脂蛋白促单核细胞粘附作用下降有关

用氧化型低密度脂蛋白处理培养的猪主动脉内皮细胞，以Ｆｉｃｏｌｌ－Ｈａｐａｑｕｅ分离液密度梯度离心分离人外周血单核细胞，观察Ｌ－精氨酸对内皮细胞－单核细胞粘附率的影响；采用反转录－多聚酶链反应技术检测氧化型低密度脂蛋白和Ｌ－精氨酸对内皮细胞血管细胞粘附分子－１表达的影响。结果显示：Ｌ－精氨酸具有剂量和时间依赖性地抑制氧化型低密度脂蛋白的促内皮细胞－单核细胞粘附作用。氧化型低密度脂蛋白处理内皮细胞能明显增加内皮血管细胞粘附分子。－１的表达，而Ｌ－精氨酸阻抑氧化型低密度脂蛋白的此种作用。结果提示Ｌ－精氨酸可能通过抑制血管细胞粘附分子－１表达阻抑氧化型低密度脂蛋白的促内皮细胞—单核细胞粘附作用。     

氧化型低密度脂蛋白促进单核细胞－内皮细胞体外粘附反应

体外培养猪胸主动脉内皮细胞，观察氧化型低密度脂蛋白对内皮细胞－单核细胞体外粘附反应的影响，同时观察氧化型低密庆脂蛋白对内皮细胞表面粘附分子颗粒膜蛋白－１４０及内皮细胞分泌前列环素的影响。结果发现氧化型低密度脂蛋白（０、５０、１００和２００ｍｇ／Ｌ）增加内皮细胞－单核细胞粘附率并呈剂量依赖性，其中以１００ｍｇ／Ｌ作用最强；氧化型低密度脂蛋白（１００ｍｇ／Ｌ）与内皮细胞孵育０．５ｈ，粘附率上升但无显著性，１ｈ后显著升高，３ｈ达高峰，４８ｈ回复接近正常水平。同时发现１００ｍｇ／Ｌ氧化型低密度脂蛋白使内皮细胞表面颗粒膜蛋白－１４０含量从９２．８±４７．６上升到２９３．０±１４０．７μｇ／Ｌ（Ｐ＜０．０５），内皮细胞分泌前列环素量从８４．６±１８．７降低到６．０±３．１ｎｇ／Ｌ（Ｐ＜０．０１）．结果表明氧化型低密度脂蛋白可显著促进单核细胞－内皮细胞粘附，其作用机制可能同内皮细胞表面粘附分子颗粒膜蛋白－１４０增加有关。关键词     

植物血凝素样低密度脂蛋白受体1的研究进展

植物血凝素样氧化型低密度脂蛋白受体1是与动脉粥样硬化的发生发展相关联的氧化型低密度脂蛋白的主要受体，介导氧化型低密度脂蛋白诱导的内皮细胞凋亡、单核细胞粘附到内皮以及衰老细胞的吞噬作用，并作用于活化的血小板和中性粒细胞，导致内皮功能障碍，进而发生动脉粥样硬化、高血压等心脑血管疾病。本文就其结构、代谢、作用、作用机制及其干预，以及它与动脉粥样硬化、高血压和心肌缺血再灌注的关系作一综述。     

基质细胞衍生因子1α对氧化型低密度脂蛋白诱导内皮细胞与单核细胞粘附的影响

目的观察基质细胞衍生因子1α对氧化型低密度脂蛋白诱导的单核细胞与内皮细胞粘附的影响。方法逆转录聚合酶链反应法和免疫印迹法分别检测内皮细胞基质细胞衍生因子1αmRNA和蛋白的表达,静态粘附实验观察氧化型低密度脂蛋白和基质细胞衍生因子1α抗体干预对内皮细胞与单核细胞粘附的影响。结果基质细胞衍生因子1α在静息状态下的血管内皮细胞上几乎不表达,随着氧化型低密度脂蛋白浓度增加和处理时间延长,基质细胞衍生因子1α的mRNA和蛋白表达水平均明显上调,25mg/L氧化型低密度脂蛋白处理48h时,基质细胞衍生因子1α表达到达峰值。氧化型低密度脂蛋白浓度为1、5、25及125mg/L时,每个视野粘附的单核细胞数分别为190±15、226±23、280±14、253±8,而正常对照组为104±10,差异有显著性意义(P<0.05)。终浓度为0.01、0.1和1μg/L基质细胞衍生因子1α抗体干预后,粘附的单核细胞数分别为202±17、142±6和115±12,明显低于对照组的279±11(P<0.05)。结论基质细胞衍生因子1α参与了内皮细胞与单核细胞的粘附。     

氧化型低密度脂蛋白介导单核细胞与血管内皮细胞粘附的单细胞定量研究

利用细胞微管吸唉技术对单核细胞与血管内皮细胞间的粘附力行单细胞定测量，以两种细胞间的临界分离应力Ｓｃ来表示细胞的粘附性，观察氧化型低密度脂蛋白对单细胞与培养人脐静脉内皮细胞附的影响。     

L-精氨酸抑制内皮细胞粘附分子-1表达与氧化型低密度脂蛋白促单核细胞粘附作用下降有关

用经型低密度脂蛋白处理培养的猪主动脉内皮细胞，以Ｆｉｃｏｌｌ－Ｈａｐａｑｕｅ分离浓密度梯度离心分离人外周血单核细胞，观察Ｌ－精氨酸对内皮细胞－单核细胞粘附率的影响，采用反转录－多聚酶链反应技术检测氧化型低密度脂蛋白和Ｌ－精氨酸对内皮细胞血管细胞粘附分子－１表达的影响。结果显示：Ｌ－精氨酸具有剂量和时间依赖性地抑制氧化型低密度脂白促内皮细胞－单核细胞粘附作用，结果提示Ｌ－精氨酸可能通过抑制血管细胞粘     

动脉粥样硬化的发生与细胞间粘附分子

动脉粥样硬化的发生与单核细胞和血管内皮细胞的粘附密切相关。单核细胞产生自由基等，使低密度脂蛋白氧化，导致动脉粥样硬化，细胞间粘附分子与配体在单核细胞与血管内皮细胞的粘附中起重要作用。ＩＬ－１、ＴＮＦ等细胞因子可能是通过细胞间粘附分子来促使动脉粥样硬化的发生和发展。核因子ｋＢ在转录水平调节细胞站粘附分子的表达、也在动脉粥样硬化的发生发展中起调节作用。     

基质细胞衍生因子1α—CXCR4趋化THP-1细胞迁移及氧化型低密度脂蛋白的影响

目的探讨基质细胞衍生因子1α对单核细胞趋化作用、氧化型低密度脂蛋白对基质细胞衍生因子1α趋化单核细胞的影响及其对THP-1细胞表达CXCR4的影响。方法用Transwell迁移实验检测基质细胞衍生因子1α对单核细胞的趋化作用，逆转录聚合酶链反应检测CXCR4 mRNA的表达，Westem blot检测CXCR4蛋白的表达，并观察氧化型低密度脂蛋白对THP-1细胞CXCR4表达的剂量和时间效应。结果基质细胞衍生因子1α呈浓度依赖性诱导单核细胞迁移，加入CXCR4抗体可明显抑制这种作用。经不同浓度氧化型低密度脂蛋白处理48h后的THP-1细胞再用10μg/L基质细胞衍生因子1α进行趋化时，氧化型低密度脂蛋白呈浓度依赖性地增加单核细胞的迁移，50mg／L氧化型低密度脂蛋白组迁移的细胞数是对照组的11倍。THP-1细胞有基础水平的CXCR4表达，50mg／L氧化型低密度脂蛋白可使CXCR4的表达上调4．5倍。CXCR4上调最早在6h内发生，12h达峰值。结论基质细胞衍生因子1α--CXCR4参与趋化单核细胞迁移，其作用被氧化型低密度脂蛋白加强；氧化型低密度脂蛋白上调CXCR4表达。     

内皮细胞形态和排列与血液动力学关系的探讨

丙丁酚阻抑氧化低密度脂蛋白介导的内皮细胞－单核细胞粘附作用李立新，陈剑雄，余麟，廖端芳，黄红林（衡阳医学院心肺药理研究室，衡阳４２１００１）用氧化低密度脂蛋白处理培养的猪胸主动脉内皮细胞，观察内皮细胞表面颗粒膜蛋白－１４０、内皮细胞－单核细胞粘附率、...     

川芎嗪对血管壁细胞血管细胞粘附分子1和单核细胞趋化蛋白1表达的作用及可能机制

目的观察川芎嗪对血管内皮细胞和平滑肌细胞表达血管细胞粘附分子1、单核细胞趋化蛋白1和核因子κB的影响,探讨川芎嗪抗动脉粥样硬化分子机制。方法体外培养人脐静脉内皮细胞和大鼠胸主动脉平滑肌细胞。用氧化型低密度脂蛋白、氧化型极低密度脂蛋白、血管紧张素Ⅱ和(或)川芎嗪作用于细胞后,采用免疫细胞化学和原位分子杂交检测各组细胞血管细胞粘附分子1、单核细胞趋化蛋白1和核因子κB的表达情况。用单核细胞粘附试验检测川芎嗪对单核细胞粘附于内皮细胞的影响。结果氧化型低密度脂蛋白、氧化型极低密度脂蛋白或血管紧张素Ⅱ诱导内皮细胞血管细胞粘附分子1蛋白相对表达量分别为0.552±0.008、0.460±0.006和0.486±0.025,明显高于对照组的0.365±0.019(P<0.01);诱导平滑肌细胞血管细胞粘附分子1蛋白相对表达量分别为0.564±0.007、0.513±0.021和0.524±0.008,明显高于对照组(0.416±0.013,P<0.01)。氧化型低密度脂蛋白、氧化型极低密度脂蛋白或血管紧张素Ⅱ诱导内皮细胞单核细胞趋化蛋白1蛋白相对表达量分别为0.962±0.051、0.878±0.014和0.824±0.006,明显高于对照组的0.303±0.008(P<0.01);诱导平滑肌细胞单核细胞趋化蛋白1蛋白相对表达量分别为0.877±0.011、0.845±0.023和0.881±0.009,明显高于对照组的0.362±0.018(P<0.01)。氧化型低密度脂蛋白、氧化型极低密度脂蛋白或血管紧张素Ⅱ诱导组血管细胞粘附分子1和单核细胞趋化蛋白1的mRNA表达明显高于对照组(P<0.01)。同时加入川芎嗪后血管细胞粘附分子1和单核细胞趋化蛋白1蛋白和mRNA表达明显低于相应诱导组(P<0.01)。氧化型低密度脂蛋白、氧化型极低密度脂蛋白或血管紧张素Ⅱ诱导核因子κB在核内表达,同时加入川芎嗪后核因子κB表达于胞浆,核内阴性。与氧化型低密度脂蛋白或氧化型极低密度脂蛋白诱导组(2.047±0.011和1.936±0.014)比较,加入川芎嗪后,粘附于内皮细胞的单核细胞明显减少(1.282±0.020和1.265±0.016,P<0.01)。结论川芎嗪通过抑制或阻断动脉粥硬化危险因素氧化型低密度脂蛋白、氧化型极低密度脂蛋白和血管紧张素Ⅱ诱导的核因子κB活化及核内移位,抑制血管壁细胞血管细胞粘附分子1和单核细胞趋化蛋白1表达,抑制单核细胞粘附于内皮,而发挥其抗动脉粥样硬化作用。     

Three layer functional model and energy exchange concept of aging process

Relying on a certain degree of abstraction, we can propose that no particular distinction exists between animate or living matter and inanimate matter. While focusing attention on some specifics, the dividing line between the two can be drawn. The most apparent distinction is in the level of structural and functional organization with the dissimilar streams of ‘energy flow’ between the observed entity and the surrounding environment. In essence, living matter is created from inanimate matter which is organized to contain internal intense energy processes and maintain lower intensity energy exchange processes with the environment. Taking internal and external energy processes into account, we contend in this paper that living matter can be referred to as matter of dissipative structure, with this structure assumed to be a common quality of all living creatures and living matter in general. Interruption of internal energy conversion processes and terminating the controlled energy exchange with the environment leads to degeneration of dissipative structure and reduction of the same to inanimate matter, (gas, liquid and/or solid inanimate substances), and ultimately what can be called ‘death.’ This concept of what we call dissipative nature can be extended from living organisms to social groups of animals, to mankind. An analogy based on the organization of matter provides a basis for a functional model of living entities. The models relies on the parallels among the three central structures of any cell (nucleus, cytoplasm and outer membrane) and the human body (central organs, body fluids along with the connective tissues, and external skin integument). This three-part structural organization may be observed almost universally in nature. It can be observed from the atomic structure to the planetary and intergalactic organizations. This similarity is corroborated by the membrane theory applied to living organisms. According to the energy nature of living matter and the proposed functional model, the decreased integrity of a human body's external envelope membrane is a first cause of the structural degradation and aging of the entire organism. The aging process than progresses externally to internally, as in single cell organisms, suggesting that much of the efforts towards the restoration and maintenance of the mechanisms responsible for structural development should be focused accordingly, on the membrane, i.e., the skin. Numerous reports indicate that all parts of the human body, like: bones, blood with blood vessels, muscles, skin, and so on, have some ability for restoration. Therefore, actual revival of not only aging tissue of the human body's membrane, but the entire human body enclosed within, with all internal organs, might be expected. We assess several aging theories within the context of our model and provide suggestions on how to activate the body's own anti-aging mechanisms and increase longevity. This paper presents some analogies and some distinctions that exist between the living dissipative structure matter and inanimate matter, discusses the aging process and proposes certain aging reversal solutions.     

Unusual responses of nocturnal pineal melatonin synthesis and secretion to swimming: Attempts to define mechanisms

Abstract: The effect of swimming at night on rat pineal melatonin synthesis was compared with that of light exposure at night. Rats were forced to swim at 0030 hr (lights out at 2000 hr) and sacrificed by decapitation 15 and 30 min later, immediately after swimming. Other groups of animals were exposed to white light (650μW/cm²) for 15 and 30 min at same time. Swimming caused a rapid and highly significant drop in the melatonin content in the pineal gland; however, the activity of N-acetyltransferase (NAT), the supposed rate limiting enzyme in the melatonin production, was not changed. Despite the drop in pineal melatonin levels, serum concentrations of the indole remained elevated in the rats that swam. In contrast, melatonin levels in the pineal and serum of light exposed rats fell precipitously, accompanied by a significant suppression of NAT activity. Since we anticipated that the strenuous exercise associated with swimming may induce release of artrial natriuretic peptide (ANP) from the heart, which in turn could cause the release of pineal melatonin, in a second study we injected physiological saline intravenously to stretch the cardiac muscle and release ANP. Three milliliters of normal saline was injected during the day into the jugular vein of anesthetized rats that were pretreated with isoproterenol to stimulate pineal melatonin production. Animals were killed 15 min after the saline injection, and pineal NAT activity and pineal melatonin levels were measured. The saline injections caused no alteration in the elevated levels of either NAT or melatonin. These data suggest that the disparity in pineal NAT activity (which was high) and pineal melatonin (which was low), in animals swum at night, may not be caused by ANP which is released during strenuous exercise such as swimming.     

Melatonin and photoperiodic time measurement: Seasonal breeding in the sheep

Abstract: Well-established circadian physiology supports the view that photoperiodic time measurement utilizes the coincidence between the presence of light and a photosensitive phase of a 'biological clock' to alter reproductive status—the so-called external coincidence model of seasonal breeding. In this review, we examine the mechanism whereby photoperiod interacts with presumed suprachiasmatic nuclei activity to allow endogenous melatonin to normally synchronize reproductive activity to the optimal time of year. The Romney Marsh sheep is particularly explored as an experimental model. It is suggested that the on/off activity of seasonal reproduction may be a robust mechanism able to be predictably manipulated by the judicious use of the light/dark cycle and exogenous melatonin, but firmly based on circadian principles.     

The immunoneuroendocrine role of melatonin

Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.     

Serological survey of HIV and syphilis in pregnant women in Madagascar

Objectives Peripartal transmission of human immunodeficiency virus (HIV) and Treponema pallidum, the causative agent of syphilis, leads to severe consequences for newborns. Preventive measures require awareness of the maternal infection. Although HIV and syphilis testing in Madagascar could be theoretically carried out within the framework of the national pregnancy follow‐up scheme, the required test kits are rarely available at peripheral health centres. In this study, we screened blood samples of pregnant Madagascan women for HIV and syphilis seroprevalence to estimate the demand for systemic screening in pregnancy. Methods Retrospective anonymous serological analysis for HIV and syphilis was performed in plasma samples from 1232 pregnant women that were taken between May and July 2010 in Ambositra, Ifanadiana, Manakara, Mananjary, Moramanga and Tsiroanomandidy (Madagascar) during pregnancy follow‐up. Screening was based on Treponema pallidum haemagglutination tests for syphilis and rapid tests for HIV, with confirmation of positive screening results on line assays. Results Out of 1232 pregnant women, none were seropositive for HIV and 37 (3%) were seropositive for Treponema pallidum. Conclusions Our findings are in line with previous studies that describe considerable syphilis prevalence in the rural Madagascan population. The results suggest a need for screening to prevent peripartal Treponema pallidum transmission, while HIV is still rare. If they are known, Treponema pallidum infections can be easily, safely and inexpensively treated even in pregnancy to reduce the risk of transmission.     

Conservative management of perforated duodenal diverticulum： A case report and review of the literature

Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.     

Changes in connexin43, the gap junction protein of astrocytes, during development of the rat pineal gland

Abstract: The abundance of gap junctions between rat pineal astrocytes formed by connexin43 (Cx43) was studied during development. Levels and distribution of Cx43 were measured by immunoblotting and indirect immunofluorescence, respectively. The amount of Cx43 in cells located within the gland was low until about the 7th postnatal day and increased to adult values between the 14th and 21st days postpartum. Although astrocytes, recognized by their vimentin immunoreactivity, were scarce before birth, they were abundant by the 7th postnatal day suggesting that the low levels of Cx43 found at this age corresponded to a low expression of this protein. Localization of the immunoreactivity to Cx43 and vimentin showed a close correlation, indicating that mature or immature pineal astrocytes form gap junctions made of Cx43. Since Cx43 levels attained their adult values at about the time the innervation and the functional state of the gland reached maturity (2–3 weeks after birth), it is proposed that astrocyte gap junctions are involved in the function of the adult rat pineal gland.