舒芬太尼后处理对大鼠心肌缺血再灌注损伤保护作用的实验研究

目的 观察不同剂量舒芬太尼(SFT)后处理的心肌保护作用.方法 健康SD雄性大鼠24只,体重250 g～300 g,随机分为假手术组、缺血再灌注组、舒芬太尼后处理低剂量组、舒芬太尼后处理高剂量组.采用结扎左冠状动脉前降支30 min再灌注120 min的方法制备心肌缺血再灌注模型.假手术组完成模型仅穿线,不结扎;假手术组穿线后腹腔注射生理盐水1 mL,缺血再灌注组缺血再灌注前2 min腹腔注射生理盐水1 mL,舒芬太尼后处理低、高剂量组分别腹腔注射舒芬太尼稀释液1 mL,2 μg/kg、10μg/kg.于实验结束时制作心肌组织匀浆,检测心肌组织中的超氧化物歧化酶(SOD)、丙二醛(MDA)含量;右心室采血常温离心分离检测血清心肌酶(CK)、血清乳酸脱氢酶(LDH)、血清一氧化氮(NO)含量,取左心室切5块,来用氯化硝基四氮唑蓝(N-BT)染色法区分正常和梗死区,用梗死区重量占左心室重量百分比观测梗死程度.结果 与假手术组比较,缺血再灌注组心肌组织SOD活性下降,MDA增高,血清CK及LDH水平增高,血清NO含量减少;与缺血再灌注模型组比较,舒芬太尼后处理组,心肌组织SOD活性升高,MDA降低,血清CK及LDH释放减少;血清NO含量增加;再灌注心律失常明显减少;心肌梗死程度降低;以舒芬太尼后处理高剂量组更为明显.结论 舒芬太尼后处理能够减轻大鼠心肌缺血再灌注损伤的程度,并且呈剂量依赖性.     

硫氮酮对心肌缺血再灌注损伤内皮功能的保护作用

目的 :研究硫氮酮对心肌缺血再灌注 (MIR)损伤内皮功能的保护作用。方法 :将 4 8只大鼠制成心肌MIR模型 ,并随机分成假手术组、MIR组、硫氮酮组。各组分别于缺血前、缺血 30min、再灌注 90min、180min检测乳酸脱氢酶 (LDH) ,肌酸磷酸激酶同工酶 (CK MB) ,一氧化氮 (NO) ,丙二醛 (MDA)含量。结果 :①MIR组与假手术组相比 ,LDH、CK MB升高 ,NO下降 ,MDA上升。②硫氮酮组与MIR组相比 ,LDH、CK MB降低 (P <0 .0 5和P <0 .0 1) ,NO活性增加 (P <0 .0 5 ) ,MDA产生减少 (P <0 .0 5 )。结论 :硫氮酮能减轻脂质过氧化程度 ,改善内皮功能 ,保护心肌MIR损伤     

Y-27632对家兔心肌缺血／再灌注损伤的有益作用

目的研究Rho激酶抑制剂Y-27632对家兔心肌缺血／再灌注损伤（IRI）是否有心脏保护作用。方法健康家兔18只，体重2．0～2．5kg，随机分为3组：IRI组、Y-27632（Y）组和假手术（C）组。用结扎左冠状动脉前降支60min后剪断结扎线恢复血流30min的方法建立在体心肌IRI模型，Y组于再灌注前5min，经耳缘静脉注射Y-276320．35mg/kg。检测左心室收缩功能，血浆肌酸激酶（CK）、乳酸脱氢酶（LDH）及心肌缺血、梗死范围。结果IRI组缺血／再灌注导致左心室舒缩功能受损，左心室收缩峰压（LVSP）、左心室内压最大上升速率（＋dp／dtmax）下降，左心室舒张末期压力（LVEDP）升高，CK、LDH的释放增加，心肌梗死范围为（5．3±0．7）％；Y组在再灌注早期LVSP、±dp／dtmax下降的幅度和LVEDP升高的幅度、CK和LDH的释放，均明显低于IRI组，组间比较P均〈0．05。心肌缺血、梗死范围也明显较IRI组小（缺血：40．5％ vs 51．3％，P〈0．05；梗死：1．7％ vs 5．3％，P〈0．01）。结论Y-27632对家兔心肌IRI有部分心脏保护作用。     

左卡尼汀对离体家兔心脏缺血再灌注损伤的保护作用

将离体兔心灌注模型随机分成三组,正常对照组连续灌注K-H液60 min;缺血再灌注组关闭主动脉套管停止灌注,30 min后恢复37℃K-H液灌注60 min;左卡尼汀组步骤同缺血再灌注组,但在复灌时先用含10mmol/L左卡尼汀的K-H液灌注30 min。记录冠脉流量、左心室发展压（LVDP）、左心室压力时间变化率（±DP/DT）;检测冠脉流出液中丙二醛（MDA）、超氧化物歧化酶（SOD）、肌酸激酶（CK）、乳酸脱氢酶（LDH）浓度和心肌组织中MDA、SOD含量。结果左卡尼汀组±DP/DTmax、LVDP较缺血再灌注组显著升高,冠脉流量增大;冠脉流出液中MDA、LDH、CK及心肌组织中MDA水平降低,SOD水平升高（P〈0.05）;超微结构损伤减轻（P〈0.05）。表明左卡尼汀具有抗兔离体心脏缺血再灌注损伤的作用。     

心肌缺血预适应对急性心肌梗死临床和近期预后价值的探讨

目的观察心肌缺血预适应对急性心肌梗死病人心肌损伤程度、恶性心律失常的发生和近期预后的影响。方法选择286例急性心肌梗死病人，分为缺血预适应组（IP组）158例，无缺血预适应组（NIP组）132例。均于入院后及入院24h内多次测定心肌肌酸激酶（CK）、肌酸磷酸激酶同工酶（CK－MB）、乳酸脱氢酶（LDH）及肌钙蛋白I（cTnI），取其峰值；比较两组恶性心律失常及心血管事件的发生率。结果1P组cK、cK－MB、LDH、cTnI峰值浓度显著低于NIP组（P〈0．01）。IP组病人心功能不全、心衰、梗死后心绞痛、恶性心律失常的发生率明显低于NIP组（P％0．01）。结论缺血预适应可减少其后发生急性心肌梗死病人心肌损伤面积，减少恶性心律失常及近期心脏事件的发生。     

心脏缺血再灌注心律失常与心肌超微结构改变关系的研究

目的研究大鼠在体心脏缺血再灌注心肌超微结构改变与再灌注心律失常关系,评价第三代肾上腺素β受体拮抗剂卡维地洛(carvedilol,CVD)对心脏缺血再灌注心肌超微结构改变及心律失常发生率的影响.方法通过左前降支冠状动脉结扎,建立大鼠在体心脏缺血再灌注损伤模型.用药组术前7 d连续胃管给CVD(1 mg/kg),结扎左前降支冠状动脉30 min后松开,进行再灌注360 min,处死动物.进行HE染色及电镜检查并观察室性心律失常变化.结果 CVD使再灌注期间室性心律失常的发生率减少了53.85%,病死率减少了57.15%(P＜0.01).CVD可减少肌酸激酶同工酶(CK-MB)、乳酸脱氢酶(LDH)及丙二醛(MDA)的释放,稳定一氧化氮(NO)的分泌.心肌HE染色及电镜检查对照组细胞明显呈片状或局灶性坏死,闰盘结构紊乱,大量反应性的中性粒性细胞浸润于坏死细胞之间,CVD组心肌细胞损伤程度明显减轻,闰盘结构基本完整,粒细胞浸润也明显减少.结论 CVD明显降低心脏缺血再灌注心律失常的发生率和病死率,对大鼠在体缺血再灌注心脏具有较强的保护作用.     

蛇床子素后处理对大鼠心肌急性缺血/再灌注损伤的保护作用

目的观察蛇床子素后处理对大鼠心肌急性缺血／再灌注损伤的作用。方法采用结扎左冠状动脉前降支制备在体大鼠急性心肌缺血／再灌注损伤模型。30只雄性Wistar大鼠随机分为伪手术（Sham）组、缺血／再灌注（I／R）组和缺血／再灌注＋蛇床子素后处理（Ost）组。采用BL-410生物信号记录分析系统记录大鼠左心室收缩压（LVSP）、左心室舒张末压（LVEDP）及左心室压力上升和下降最大速率（＋dp／dtmax）等心功能数据。实验结束后腹主动脉采血,采用ELISA方法检测血清肌酸激酶同工酶（CK—MB）、肌钙蛋白I（cTnI）含量,应用透视电镜对左室心尖部心肌组织超微结构进行形态学观察。结果与Sham组相比,I／R组大鼠心肌超微结构发生明显改变,心脏收缩、舒张功能显著降低,血清CK—MB及cTnI含量均显著增高。与I／R组比较,Ost组大鼠心肌超微结构损伤明显减轻,心功能明显改善,血清CK—MB及cTnI含量显著降低。结论蛇床子素后处理对急性心肌缺血／再灌注所致的大鼠心肌损伤具有保护作用。     

辛伐他汀缺血后处理对大鼠心肌缺血再灌注损伤的保护作用

目的探讨辛伐他汀缺血后处理对大鼠心肌缺血再灌注（I/R）损伤的保护作用及机制。方法采用Langendorff离体心脏灌流模型,将32只大鼠随机分为四组各8只。对照组用改良K-H缓冲液持续灌流;I/R组用改良K-H缓冲液稳定灌注、停灌、再灌;治疗组用改良K-H缓冲液稳定灌注、停灌后,在K-H缓冲液中加入辛伐他汀20μmol/L再灌;K-H缓冲液再灌;N-硝基-L-精氨酸甲酯（L-NAME）组用改良K-H缓冲液稳定灌注、停灌后,在K-H缓冲液中加入辛伐他汀20μmol/L、L-NAME 100μmol/L再灌,K-H缓冲液再灌。观察各组再灌注心律失常发生情况,检测其冠脉流出液中的肌酸激酶（CK）、乳酸脱氢酶（LDH）、NO,心肌组织总超氧化物歧化酶（T-SOD）活性、丙二醛（MDA）及细胞凋亡指数（AI）。结果与I/R组比较,治疗组心律失常发生率下降,CK、LDH、MDA及细胞AI降低,T-SOD活性、NO升高（P均〈0.01）;与治疗组比较,L-NAME组心律失常发生率升高,CK、LDH、MDA及细胞AI升高,T-SOD活性、NO降低（P均〈0.01）。结论辛伐他汀缺血后处理能减轻大鼠心肌I/R损伤,其作用机制与清除氧自由基、增加NO含量、减少心肌细胞凋亡有关。     

肾脏缺血后处理对AMI患者心肌再灌注损伤的保护作用

将88例急性心肌梗死（AMI）行急症介入患者随机分为冠脉介入（PCI，A组）30例，PCI术前行肾脏缺血后处理（B组）28例，PCI术后行肾脏缺血后处理（C组）30例。观察各组心肌酶学（CK—MB）、丙二醛（MDA）变化，以及左室射血分数（LVEF）、心肌收缩期室壁增厚率（△T）、左室收缩末期容量（LVESV）等变化。结果B、C组较A组MDA、CK—MB峰值明显下降，LVEF、AT、LVESV明显改善。提示肾脏缺血后处理可明显减少AMI患者急症介入治疗引起的心肌再灌注损伤，改善心功能。     

法舒地尔对大鼠离体心脏缺血/再灌注损伤的保护作用

目的观察盐酸法舒地尔对大鼠离体心脏缺血/再灌注（I/R）损伤是否有保护作用。方法SD大鼠19只,随机分为3组:I/R组、I/R+F组和对照组。用改良的Langendorff灌流装置,用K-H液行主动脉逆行灌流,建立大鼠离体心脏I/R损伤实验模型。I/R组预灌流20 min,停灌45 min,再灌30 min;I/R+F组于再灌注时在灌流液中加入盐酸法舒地尔注射液（10 mg/kg）;对照组连续灌流95 min。连续记录左心室收缩功能曲线,收集冠脉流出液,检测冠脉流出液中乳酸脱氢酶（LDH）、肌酸激酶（CK）、肌红蛋白（Mb）漏出量以及心肌细胞内钙、心肌组织一氧化氮（NO）含量和髓过氧化物酶（MPO）活力。结果心肌缺血使冠脉流出量减少,LDH、CK、Mb增加,再灌注后冠脉流出量进一步减少,LDH、CK、Mb进一步增加,同时增加细胞内钙,增加MPO活力,减少NO生成。盐酸法舒地尔逆转再灌注后冠脉流出量减少和LDH、CK和Mb漏出增加,降低细胞内钙、MPO活力,逆转NO生成减少。I/R使左室发展峰压平均值、平均±dp/dtmax均下降,盐酸法舒地尔对左室发展峰压的改变无明显影响,但改善±dp/dtmax降低。结论盐酸法舒地尔对心肌I/R损伤有保护作用,增强I/R引起的"无复流"现象和心肌收缩能力降低的恢复,此作用与逆转NO生成减少、MPO活性增高和细胞内钙超载等因素有关。     

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.     

Response of rat pineal melatonin to calcium, magnesium, and lithium is circadian stage dependent

Abstract: Herein we documented the response of pineal melatonin production to electrolytes known to be effective on pineal function in view of a possible circadian stage dependence. We studied the release of melatonin by perifused rat pineal glands at 2 different circadian stages corresponding to the middle of the light and dark periods, i.e., respectively, 7 and 19 HALO (Hours After Light Onset, L:D = 12:12). The initial efflux rates were, as expected, much higher in the perifusates of glands removed from rats sacrificed during the dark phase than of those removed during the light phase. After 3 hr of perifusion, melatonin release reached similar levels which were found constant up to the 8th hr of perifusion, whatever the circadian stage. Perifusion of the glands with physiological concentrations for the rat of calcium (5.2 mmol/1) and magnesium (1.34 mmol/1) resulted in a stimulatory effect on the pineal glands removed from rats sacrificed in the middle of the dark period (19 HALO), whereas no effects were observed on the pineal glands removed from rats sacrificed during the light (7 HALO). Lithium (0.28 and 0.55 mmol/1) was ineffective on melatonin release in pineal glands removed 7 and 19 HALO. Our results show differences in the initial efflux rates of melatonin and in the response of perifused pineal glands to calcium and magnesium according to the circadian stage.     

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.