人参三七配伍对脑缺血再灌注损伤小鼠血脑屏障通透性及脑组织炎症反应的影响

目的观察人参和三七配伍提取物对脑缺血再灌注损伤(CIRI)小鼠血脑屏障(BBB)通透性及脑组织炎症反应的影响。方法通过结扎小鼠双侧颈总动脉制备CIRI模型。用红四氮唑(TTC)染色测定CIRI小鼠脑梗死比和脑组织含水量,通过测定渗出脑血管外的伊文思蓝含量,分析人参三七配伍对CIRI小鼠BBB通透性的影响;光学显微镜下观察CIRI小鼠脑组织病理形态,采用酶联免疫法(ELISA)检测小鼠脑组织中白细胞介素(IL)-1β、IL-10、肿瘤坏死因子(TNF)-α的表达水平。结果人参和三七配伍的提取物可明显减少CIRI小鼠脑梗死比及脑组织含水量、降低小鼠脑组织中伊文思蓝含量、改善BBB通透性和脑组织病理状态、降低脑组织IL-1β和TNF-α的表达水平、增加脑组织IL-10的表达水平。结论人参和三七配伍提取物对CIRI小鼠具有显著保护作用,其机制与降低CIRI小鼠BBB通透性及脑组织炎症反应有关。     

原花青素对脑缺血再灌注损伤大鼠血脑屏障通透性和自由基含量的影响

目的 探讨原花青素(procyanidin,PC)对缺血再灌注损伤大鼠脑组织含水量、血脑屏障通透性和自由基含量的影响.方法 将大鼠随机分为假手术组、缺血再灌注组、PC低剂量治疗组和PC高剂量治疗组,线栓法建立局灶性脑缺血再灌注模型.观察缺血90 min再灌注24 h大鼠脑含水量和伊文斯蓝(EB)含量变化及超氧化物歧化酶(SOD)、丙二醛(MDA)含量变化,并进行2,3,5-三苯基氯化四氮唑(TTC)染色.结果 与假手术组比较,缺血再灌注组脑含水量和EB含量明显升高;与缺血再灌注组比较,PC高、低剂量治疗组脑含水量和EB含量明显降低(P<0.05),高、低剂量组之间差异亦具有统计学意义(P<0.05).与缺血再灌注组比较,PC治疗组显著降低MDA含量,增加SOD活性,高、低剂量组之间差异亦有统计学意义(P<0.05).PC高、低剂量治疗组脑梗死体积较缺血再灌注组减小,高、低剂量组之间差异具有统计学意义(P<0.05).结论 PC对缺血再灌注脑损伤具有保护作用,可能与减轻再灌注损伤后血脑屏障通透性和氧化性损伤有关.     

金纳多对脑缺血再灌注损伤大鼠MMP-9活性和血脑屏障通透性的影响

目的探讨金纳多对大鼠脑缺血再灌注损伤的保护作用。方法采用线栓法制备大鼠局灶性脑缺血再灌注损伤模型,将成模大鼠随机分为假手术组、缺血再灌注组、金钠多治疗组,各组按缺血再灌注6、12、24 h三个时间点分为3个亚组,每组10只。用RT-PCR方法测定损伤侧脑组织中MMP-9活性变化,用伊文思蓝方法测定同侧脑组织血脑屏障通透性。结果 (1)随缺血再灌注时间延长,MMP-9含量、EB含量开始逐渐增加,各组之间表达差异均具有统计学意义(P<0.05)。(2)金纳多治疗组MMP-9活性及EB含量各个时间点明显低于缺血再灌注组(P<0.05)。结论金纳多通过抑制脑缺血再灌注大鼠MMP-9的活性,减轻血脑屏障通透性,可能是其发挥脑保护作用的机制之一。     

补阳还五汤对大鼠脑缺血再灌注损伤后血脑屏障的影响

目的 观察补阳还五汤对大鼠脑缺血再灌注损伤后血脑屏障的影响并探讨其影响机制。方法 48只SD大鼠随机分为3组：①假手术组（n=16）；②对照组（n=16）；③补阳还五汤组（n=16）。线栓法制作大鼠脑缺血再灌注模型，再灌注48h后干湿重法测定缺血脑组织含水量，经股静脉注射伊文思蓝观察血脑屏障的通透性，取缺血脑组织提取总RNA和蛋白质分别应用逆转录聚合酶链反应和Western杂交技术检测基质金属蛋白酶9的转录及表达情况，同时电镜观察血脑屏障的变化。结果 脑缺血再灌注48h，对照组缺血侧脑含水量明显升高，伊文思蓝含量也明显增加，电镜观察发现血脑屏障破坏严重，基质金属蛋白酶9的转录与表达也较假手术组显著增加；而应用补阳还五汤处理的大鼠其缺血脑组织含水量明显减少，缺血侧伊文思蓝含量较对照组也明显降低（P〈0．05），同时电镜观察到血脑屏障的破坏减轻，而基质金属蛋白酶9mRNA和蛋白表达水平也明显低于对照组。结论 对大鼠脑缺血再灌注损伤后的血脑屏障具有保护作用，其作用机制可能是通过抑制基质金属蛋白酶9的转录和表达来实现的。     

姜黄素对脑缺血再灌注损伤大鼠MMP-2活性和血脑屏障通透性的影响

目的探讨姜黄素降低脑缺血再灌注损伤大鼠血脑屏障通透性及减轻脑水肿的作用及机制。方法将90只SD大鼠随机分为假手术组(n=30)、缺血再灌注组(n=30)、姜黄素治疗组(n=30)。以线栓法制备局灶性脑缺血再灌注损伤大鼠模型,腹腔注射姜黄素,各组于脑缺血再灌注后24 h、48 h、96 h用免疫组织化学方法观察损伤侧脑组织基质金属蛋白酶(MMP)-2活性及层黏连蛋白表达的变化。比色法测定损伤侧脑组织含有伊文思蓝(EB)的量,动态观察该侧血脑屏障通透性变化。结果随着缺血再灌注时间逐渐延长,MMP-2表达能力、EB含量均逐渐增加,48 h达峰,层黏连蛋白的表达逐渐下降,各组之间表达具有统计学差异(P0.05);姜黄素治疗组MMP-2表达、EB含量在各个时间点明显低于缺血再灌注组,同时层黏连蛋白的表达增加(P0.05)。结论姜黄素可抑制脑缺血再灌注损伤大鼠MMP-2的表达,增加层黏连蛋白的表达,降低血脑屏障通透性,从而减轻脑水肿。     

川芎嗪减轻大鼠心肌缺血再灌注损伤炎症反应及机制

目的观察川芎嗪预处理对大鼠心肌缺血再灌注损伤炎症反应的影响并探讨其可能的机制。方法 48只雄性SD大鼠随机分为假手术组、缺血再灌注组、川芎嗪组、左旋-硝基-精氨酸甲酯组以及川芎嗪+左旋-硝基-精氨酸甲酯组,假手术组左前降支近端穿线但不结扎,其余四组给予结扎前降支缺血35 min,再灌注120 min。光镜观察大鼠心肌组织结构变化,测定缺血心肌组织超氧化物歧化酶活性和丙二醛含量及髓过氧化物酶、白细胞介素1β、一氧化氮含量,逆转录聚合酶链反应和免疫印迹法测定心肌内皮型一氧化氮合酶mRNA和蛋白的表达水平。结果与缺血再灌注组相比,川芎嗪预处理能减少心肌白细胞浸润,增加心肌组织超氧化物歧化酶活性,降低丙二醛含量及髓过氧化物酶活性,降低白细胞介素1β水平,增加一氧化氮含量及心肌内皮型一氧化氮合酶mRNA和蛋白的表达水平,左旋-硝基-精氨酸甲酯显著抑制上述指标的变化并取消了川芎嗪所致的内皮型一氧化氮合酶mRNA和蛋白表达水平的增加。结论川芎嗪预处理能减少大鼠心肌缺血再灌注损伤的炎症反应,其机制可能与上调内皮型一氧化氮合酶表达,增加内源性一氧化氮水平有关。     

胸腺素β4对大鼠局灶性脑缺血再灌注损伤后血脑屏障的影响

目的：观察胸腺素β4对大鼠局灶性脑缺血再灌注损伤后血脑屏障的影响,并探讨其作用机制。方法将72只SD大鼠随机分为假手术组、对照组、胸腺素β4组各24只。采用线栓法制作大鼠大脑中动脉闭塞局灶性脑缺血再灌注模型,再灌注24 h后,采用干湿重法测定缺血脑组织含水量,通过检测伊文蓝渗透到缺血侧脑组织的含量观察血脑屏障的通透性,应用RT-PCR法检测缺血脑组织紧密连接蛋白5（ Claudin-5）和基质金属蛋白酶-9（MMP-9） mRNA表达。结果脑缺血再灌注损伤24 h后,与假手术组比较,对照组缺血侧脑含水量、伊文蓝含量、MMP-9 mRNA表达明显增加,Claudin-5 mRNA表达显著减少（ P均＜0．01）;与对照组比较,胸腺素β4组缺血侧脑组织含水量、缺血侧伊文蓝含量、MMP-9 mRNA明显降低,Claudin-5 mRNA表达明显升高（P均＜0．01）。结论胸腺素β4对大鼠脑缺血再灌注损伤后的血脑屏障具有保护作用,其作用机制可能是通过促进Claudin-5 mRNA表达和抑制MMP-9 mRNA表达实现的。     

大鼠脑缺血再灌注中血脑屏障通透性的改变与基质金属蛋白酶9表达的关系

目的探讨大鼠脑缺血再灌注中基质金属蛋白酶9的表达变化与血脑屏障通透性改变的关系。方法采用大鼠右侧大脑中动脉缺血再灌注模型,通过测定渗出血管外的伊文思蓝含量来评价血脑屏障通透性的变化,采用免疫组织化学的方法检测各组大鼠脑基质金属蛋白酶9的表达。90只大鼠用于上述实验检测,分别为对照组、假手术组、缺血2h后再灌注3h、6h、12h、1d、2d、4d和7d组共9小组,每组5只。结果与对照组和假手术组比较脑缺血再灌注后3h脑组织伊文思蓝渗出量增加(0.18±0.08比0.86±0.12μg/g),1d后达到高峰(4.64±1.27μg/g),2d以后逐渐减小(4.48±0.65μg/g)。基质金属蛋白酶9表达阳性细胞在缺血再灌注12h(3.64±0.56比6.76±2.26)、1d(11.24±2.64)、2d(21.52±2.03)、4d(16.66±1.38)和7d(14.64±3.77)均显著增加,其中2d为高峰期。结论脑缺血再灌注时基质金属蛋白酶9阳性细胞的表达与血脑屏障通透性的增加呈时间相关性,提示基质金属蛋白酶9参与了脑缺血急性期血脑屏障的破坏。     

阿司匹林预处理对大鼠局灶性脑缺血再灌注损伤的神经保护作用

目的探讨阿司匹林预处理对大鼠局灶性脑缺血再灌注损伤的保护作用机制。方法SD大鼠随机分为假手术组、脑缺血再灌注组、阿司匹林预处理组。各组采用大脑中动脉线栓法制备缺血再灌注损伤实验动物模型。比较各组神经功能缺失评分、脑梗死体积、血清神经元烯醇化酶(NSE)含量及脑组织白细胞介素-1β(IL-1β)和肿瘤坏死因子(TNF-α)含量。结果阿司匹林预处理组可使神经功能缺损减轻、脑梗死体积缩小、血清NSE含量降低,均较脑缺血再灌注组明显。同时脑组织IL-1β和TNF-α含量亦较脑缺血再灌注组降低。结论阿司匹林预处理可诱导脑缺血耐受作用,其机制可能与下调脑组织再灌注损伤时IL-1β和TNF-α的表达有关。     

阿司匹林联合脑缺血预处理对大鼠脑缺血再灌注后炎性反应的影响

目的 探讨阿司匹林(ASA)联合脑缺血预处理治疗对大鼠脑缺血再灌注损伤的保护作用及其机制.方法 SD大鼠随机分为假手术组、脑缺血再灌注组、脑缺血预处理组和ASA治疗组.各组采用Zea-Longa等的大脑中动脉线栓法并加以改进,制备缺血预处理及缺血再灌注损伤实验动物模型.在相应时间点比较各组神经功能缺失评分、脑梗死体积、血清神经元烯醇化酶(NSE)含量及脑组织白细胞介素(IL)-1β和肿瘤坏死因子(TNF)-α含量.结果 ASA联合脑缺血预处理可使神经功能缺损减轻、脑梗死体积缩小、血清NSE含量降低,均较缺血预处理组更为明显.脑组织IL-1β和TNF-α含量降低亦更为明显.结论 ASA可增强缺血预处理诱导的脑缺血耐受作用,下调脑组织再灌注损伤时IL-1β和TNF-α的表达,二者具有叠加作用.     

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.     

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.     

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.     

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.     

Language of CTO interventions – Focus on hardware

The knowledge of variety of chronic total occlusion (CTO) hardware and the ability to use them represents the key to success of any CTO interventions. However, the multiplicity of CTO hardware and their physical character and the terminology used by experts create confusion in the mind of an average interventional cardiologist, particularly a beginner in this field. This knowledge is available but is scattered. We aim to classify and compare the currently used devices based on their properties focusing on how physical character of each device can be utilized in a specific situation, thus clarifying and simplifying the technical discourse.     

High prevalence of distal sensory polyneuropathy in antiretroviral-treated and untreated people with HIV in Tanzania

Objectives To describe the prevalence of distal sensory polyneuropathy (DSP), a complication of both advanced HIV disease and of antiretroviral therapy (ART), amongst Tanzanians with HIV, on and off ART (including stavudine) with CD4 counts above and below 200 cells/μl. Methods We recruited participants attending ART clinic into four groups: >6 months ART exposure and (i) CD4 < 200 cells/μl or (ii) CD4 > 200 cells/μl (ART/CD4 < 200 and ART/CD4 > 200, respectively); ART‐naïve and (iii) CD4 < 200 cells/μl or iv)CD4 > 200 cells/μl (noART/CD4 < 200 and noART/CD4 > 200, respectively). Primary outcome was DSP, as defined by presence of at least one symptom and one sign. Results Of 326 evaluable participants, 81 (32 men, median age 38 years, median CD4 142 cells/μl) were enrolled in the ART/CD4 < 200 group, 78 (17 men, median age 37 years, median CD4 345 cells/μl) in ART/CD4 > 200, 81 (30 men, median age 37 years, median CD4 128 cells/μl) in noART/CD4 < 200 and 86 (22 men, median age 33 years, median CD4 446 cells/μl) in noART/CD4 > 200. Numbness was the most commonly reported symptom. DSP prevalence ranged from 43.2% in ART/CD4 < 200 to 20.9% in noART/CD4 > 200. DSP was more common among men (adjusted odds ratio [aOR] 1.9, 95% confidence interval [CI] 1.2–3.3) and older participants (aOR 2.7, 95% CI 1.1–6.2 for age 40 + vs. <30 years). Conclusion Distal sensory polyneuropathy is common amongst those attending this clinic, even those with no ART exposure and a CD4 count above 200 cells/μl. Stavudine and didanosine expose HIV‐infected patients to an additional avoidable risk of DSP. Access to non‐neurotoxic ART regimes as well as earlier HIV diagnosis and initiation of ART is needed.