miR-21对心肌梗死大鼠心室重塑的影响

目的探讨miR-21对心肌梗死大鼠心室重塑的影响。方法选取80只SD大鼠作为研究对象,使用结扎前降支动脉法建立大鼠急性心肌梗死模型,将80只大鼠分为实验组和对照组,各40只。将两组大鼠心肌组织及梗死交界部位的心肌组织RNA、miRNA提取出保存备用,采用荧光定量聚合酶链式反应(PCR)法测定心肌组织肌球蛋白重链(MHC)-βRNA、miR-21表达情况,使用末端标记法检测并比较两组大鼠心肌细胞凋亡情况。结果实验组大鼠心肌梗死术后7 d、28 d心肌组织miR-21、MHC-βRNA表达量均明显高于对照组(P0.05),且心肌梗死术后28 d miR-21、MHC-βRNA表达量明显高于术后7 d(P0.05)。实验组大鼠心肌梗死术后7 d、28 d细胞凋亡指数均明显高于对照组(P0.05),且术后28 d细胞凋亡指数明显高于术后7 d(P0.05)。结论大鼠心肌梗死后心室重塑过程中miR-21表达量明显升高,提示miR-21与心肌梗死后心室重塑有关。     

携带肝细胞生长因子基因的重组腺病毒修复烟熏致大鼠肺气肿的作用

目的 通过构建大鼠肺气肿模型,观察携带肝细胞生长因子基因的重组腺病毒(Ad-HGF)对肺气肿病变的修复作用.方法 40只Wistar大鼠随机分为4组:肺气肿组(A组)、肺气肿+Ad-HGF 组(B组)、肺气肿+Ad-GFP组(c组)和正常对照组(D组);采用烟熏法建立大鼠肺气肿模型.A组给予0.5 ml生理盐水灌注治疗,B组给予1×10 9 pfu Ad-HGF,C组给予1×10 9 pfu Ad-GFP,D组正常饲养;干预后14 d取腹主动脉血,作动脉血气分析.取C组大鼠部分肺组织作常规冰冻切片,荧光显微镜下观察目的 基因的表达;取A,B,D组大鼠肺组织制作病理切片,观察并计算平均肺泡面积(MAA);采用脱氧核糖核酸末端转移酶介导的dUTP缺口末端标记技术和增殖细胞核抗原免疫组织化学法对大鼠肺实质凋亡细胞、增殖细胞的阳性细胞率(AI、PI)进行检测.结果 与D组相比,A组、B组、C组大鼠的肺组织都存在不同程度的肺气肿病理改变,肺组织切片中Ad-HGF治疗组病理改变明显轻于模型组;各组大鼠动脉血气分析比较,差异无统计学意义(P>0.05);Ad-HGF治疗组MAA[-(4 227.63±156.01),μm2] 显著小于模型组[(6 346.35±148.60)μm2,P＜0.05] ,Ad-HGF治疗组AI[(18.95±2.27)%] 显著低于模型组[(23.41±3.55)%,P＜0.05] ,以上两组AI均高于正常对照组[(5.40±1.22)%,P＜0.05] ;Ad-HGF治疗组PI[(17.51±1.89)%] 显著高于模型组[(15.51±2.75)%,P＜0.05] ,以上两组PI均高于正常对照组[(5.44±1.80)%,P＜0.05] .结论 Ad-HGF对烟熏大鼠肺气肿有修复作用.     

蒙药顺气补心十一味丸对心肌梗死大鼠心肌血管生成和VEGF表达的影响

目的探讨顺气补心十一味丸对心肌梗死后缺血心肌血管生成的作用以及可能机制。方法健康成年Wistar大鼠72只,随机分为模型对照组、蒙药低剂量组、蒙药高剂量组、卡托普利组,每组18只。所有大鼠背部皮下多点注射盐酸异丙肾上腺素(ISO)复制心肌梗死模型,模型建立后,药物干预组分别给予顺气补心十一味丸0.461、1.844 g/kg和卡托普利25 mg/kg,每日两次灌胃。分别取6只大鼠在7、28 d和42 d处死,免疫组化染色观察CD34和血管内皮生长因子(VEGF)蛋白表达。结果①MVD结果显示:7、28 d和42 d蒙药低、高剂量组、卡托普利组与模型对照组相比MVD明显增加(P<0.01);②VEGF蛋白在7、28 d和42 d时蒙药低、高剂量组与模型对照组相比表达明显增强(P<0.01);卡托普利组与模型对照组相比无差异。③病理结果显示:相应时间点各治疗组较模型对照组坏死灶面积缩小,42 d时心肌纤维化程度减轻。结论顺气补心十一味丸能够促进心肌梗死大鼠缺血心肌的血管生成,能上调缺血心肌的VEGF蛋白表达,其促血管生成的机制可能与上调缺血心肌的VEGF蛋白表达有关。     

碱性成纤维细胞生长因子基因对猪缺血心肌侧支血管生成的作用

目的探讨经导管冠状动脉内注射碱性成纤维细胞生长因子(bFGF)基因(pcDNA3-bFGF)对猪缺血心肌侧支血管生成的作用。方法实验猪分为3组:手术对照组(n=6)、bFGF基因左冠状动脉注射组(n=6)和bFGF基因右冠状动脉注射组(n=6)。开胸结扎冠状动脉左回旋支(LCX),建立急性心肌梗死动物模型。术后2周,分别行选择性冠状动脉造影,并经导管冠状动脉内注射pcD-NA3-bFGF 2 000μg。给药后2周,再次行选择性冠状动脉造影观察冠状动脉侧支血管形成情况,并通过病理切片光镜观察、免疫组化染色进行血管计数,观察猪缺血心肌侧支血管生成情况。结果(1)病理切片及免疫组化染色结果显示左、右冠状动脉注射基因组血管计数较对照组明显增加;(2)术后4周选择性冠状动脉造影显示左、右冠状动脉注射基因组侧支血管明显多于对照组,左冠状动脉注射基因组侧支血管多于右冠状动脉基因注射组。结论经导管冠状动脉内注射bFGF基因能促进猪缺血心肌侧支血管生成。     

重组腺相关病毒介导的CD151基因转移对大鼠缺血心肌血管密度的影响

目的通过将携带人CD151基因的重组腺病毒相关病毒（rAAV）载体注入缺血心肌,观察CD151基因对缺血心肌血管密度的影响。方法结扎冠状动脉前降支制作大鼠急性心肌梗死模型,将rAAV-CD151注入缺血心肌处。4周后取注射部位心肌,用逆转录聚合酶链式反应（RT-PCR）检测外源性CD151 mRNA的表达、Western blot检测CD151的表达、Ⅷ因子相关抗原免疫组化染色并计数注射部位心肌毛细血管数目,评价外源CD151对毛细血管密度的影响。结果术后4周,CD151组心肌组织检测到外源性CD151 mRNA的表达,假手术组、缺血对照组、GFP组未检测到外源性CD151 mRNA的表达,且CD151组心肌组织CD151蛋白表达水平高于假手术组、缺血对照组、GFP组（P<0.01）;CD151组血管密度与缺血对照组、GFP组比较显著增加（P<0.01）。结论rAAV-CD151可以有效地转染大鼠心肌组织,促进缺血心肌的血管生成。     

心肌内注射腺病毒介导血管内皮生长因子基因的血管生成实验研究

目的探讨血管内皮生长因子165(VEGF165)基因的血管生成作用. 方法在猪冠状动脉回旋支起始处放置Ameroid闭合器,制备慢性心肌缺血模型,28 d时行选择性冠状动脉造影,观察回旋支狭窄程度.开胸,治疗组(6只)在缺血区心肌内多点注射含人VEGF165基因的重组腺病毒载体(Ad-VEGF165);对照组(6只)在缺血区心肌内多点注射含细菌半乳糖苷酶基因的重组腺病毒载体(Ad-β-gal).转染重组腺病毒载体28 d时重复行冠状动脉造影后,处死猪,取缺血区心肌,做组织学检查;应用酶标法检测血浆中VEGF浓度,采用Rentrop分级、缺血区心肌侧支血管积分和心肌碱性磷酸酶染色法评价血管生成作用. 结果与对照组比较,基因转染3 d时治疗组血浆VEGF增高[(114.6±5.4)pg/ml对(60.3±1.8)pg/ml,P<0.001],7 d时血浆VEGF为(128.4±3.0)pg/ml对(70.9±5.3)pg/ml,P<0.001,14 d后恢复到基线水平.与对照组比较,基因转染28 d时治疗组Rentrop分级增高(2.8±0.4对1.3±0.8,P<0.001),侧支血管积分增高(4.8±0.8对1.7±0.8,P<0.001),缺血区毛细血管密度增高(210±19对62±6,P<0.001). 结论心肌转染Ad-VEGF165后,缺血心肌表达VEGF,产生了血管生成作用.     

CD151基因转移对大鼠缺血心肌VEGF表达影响的实验研究

目的 通过将携带人CD151基因的重组腺病毒相关病毒(rAAV) 载体注入缺血心肌, 观察CD151对缺血心肌VEGF表达的影响.方法 制作大鼠急性心肌梗死模型,将rAAV-CD151注入缺血心肌.4 w后取注射部位心肌,用逆转录聚合酶链式反应(RT-PCR)检测外源性CD151 mRNA的表达、Western印迹法检测CD151及VEGF的表达情况,了解高表达CD151对VEGF表达的影响.结果 术后4 w,CD151组心肌组织检测到外源性CD151 mRNA的表达,假手术组、对照组、GFP组未检测到外源性CD151 mRNA的表达,且CD151组心肌组织CD151蛋白表达水平高于假手术组、对照组、GFP组(均P＜0.05);CD151组VEGF表达无明显增加,与对照组、GFP组比较无明显增加(均P＞0.05).结论 rAAV-CD151可以有效转染大鼠心肌组织,促进缺血心肌的血管生成,改善左室功能,但对VEGF表达没有影响.     

血管生成素相关蛋白2对大鼠缺血心肌促血管生长作用的初步观察

目的观察和评价血管生成素相关蛋白2(angiopoietin-related protein 2,ARP2)基因移植于大鼠急性缺血心肌后的促血管新生作用,探讨其促血管新生机制。方法建立急性心肌缺血大鼠模型,将42只大鼠随机分为3组:缺血区域心肌内注射ARP2重组腺病毒组(Ⅰ组,n=14);注射ARP2空腺病毒组(Ⅱ组,n=14)和注射磷酸缓冲溶液组(Ⅲ组,n=14),注射后28天行心脏彩色超声检查、心肌声学造影,并取注射点心肌切片作常规病理HE染色、VB染色、Ⅷ因子相关抗原免疫学检测。结果Ⅰ组大鼠心脏功能及心肌灌注较Ⅱ、Ⅲ组明显改善,免疫组织化学检测显示Ⅰ组心肌高度表达ARP2蛋白,心肌纤维间毛细血管数目明显增多。结论ARP2能通过促进大鼠缺血心肌血管新生,从而改善心脏功能。     

碱性成纤维细胞生长因子在鼠缺血心肌中表达及其促血管新生作用

目的 探讨腺病毒穿梭质粒介导的碱性成纤维细胞生长因子(bFGF)基因质粒在大鼠缺血心肌中的表达情况及其对缺血心肌血管新生、梗死面积的影响.方法 42只健康SD大鼠接受冠状动脉左前降支结扎术,存活30只,随后随机分为治疗组(n=15)和对照组(n=15),治疗组于心肌梗死区和正常区交界处局部注射100 μl bFGF基因(1 μg/μl),对照组以等体积生理盐水处理.4 w后观察红色荧光蛋白(RFP)和bFGF 表达情况.微血管计数和氯化三苯四氮唑(TTC)分别检测血管新生情况和梗死面积.结果 ①基因转染后4 w的心肌冰冻切片中均可见RFP表达;治疗组心肌组织bFGF mRNA表达水平较对照组明显增高[1.238±0.323 vs 0.771±0.102(P＜0.05)],仅在治疗组检测到bFGF 蛋白表达.②治疗组微血管密度明显高于对照组[141.13±17.65 vs 75.58±6.59/视野(P＜0.05)];治疗组梗死面积小于对照组[16.32±0.43 vs 17.00±0.57%(P＜0.05)].结论 重组bFGF裸质粒经心肌内直接注射后能有效表达并发挥促进梗死后心肌血管新生和缩小梗死面积的作用.     

G-CSF对急性心肌梗死大鼠心室重构的影响

通过结扎冠状动脉前降支建立大鼠急性心肌梗死(AMI)模型,将大鼠随机分成四组:AMI后1周模型组、AMI后人重组粒细胞集落刺激因子(rhG-CSF)治疗1周组、AMI后2周模型组、AMI后rhG-CSF治疗2周组.另设1、2周假手术组各8只.治疗组皮下注射rhG-CSF 5 μg/(kg·d),连续7 d;AMI模型组和假手术组皮下注射等量生理盐水.测量各组心室重构参数.结果 与假手术组比较,AMI后1周,心室腔明显扩大(P<0.05);AMI后2周时,心室腔内径扩大更明显(P<0.01),且心室质量指数(VWI)比假手术组明显增加(P<0.05);rhG-CSF治疗2周组VWI低于AMI后2周模型组,心室腔扩大程度小于模型组(P<0.05).认为注射rhG-CSF可动员自体骨髓干细胞,缩小梗死面积,改善大鼠AMI后心室重构,促进梗死处血管再生及细胞增殖.     

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.