分化抑制因子1对结肠癌HT-29细胞增殖的影响

目的 检测分化抑制因子1(Id1)对结肠癌HT-29细胞VEGF表达的影响,探讨其在结肠癌增殖中的作用.方法 HT-29转染Id1表达质粒,RT-PCR方法和Western印迹法检测血管内皮生长因子(VEGF) mRNA和蛋白的表达,MTT法检测各组细胞增殖情况;合成Id-1干扰序列转染HT-29细胞后,RT-PCR及Western印迹检测HT-29细胞VEGF mRNA和蛋白的表达情况,采用MTT法检测各组细胞增殖情况.结果 Id1表达质粒空白组、对照组(空载体组)、过表达组VEGF/GAPDH mRNA分别为:0.002 99±0.000 687、0.003 49±0.001 34、0.0313±0.00605(P＜0.01);VEGF/GAPDH蛋白分别为:0.132±0.035 1、0.131±0.053 0、0.245 ±0.032 6(P ＜0.01),MTT实验显示相对对照组,过表达组增殖明显快(P＜0.01).Id-1干扰空白组、对照组(空载体组)、抑表达组VEGF/GAPDH mRNA分别为:0.006 16±0.000 829、0.006 26±0.000 447、0.002 3±0.000 308(P ＜0.01);VEGF/GAPDH蛋白分别为:0.450 ±0.039 3、0.464±0.023 1、0.231±0.027 3(P ＜0.01).MTT实验显示相对对照组,抑表达组增殖明显减慢(P＜0.01).Id1过表达能显著上调VEGF mRNA和蛋白表达,提高细胞的生长,Id1抑制后能显著下调VEGF mRNA和蛋白表达,减缓细胞的生长.结论 在结肠癌HT-29细胞中Id1为VEGF的上游基因,Id1通过Id1 ↑ →VEGF ↑途径来影响结肠癌细胞增殖,在肿瘤血管生成中发挥重要作用.Id1有望成为结肠癌治疗的一个新靶点.     

塞莱昔布对结肠癌细胞生长及肝转移瘤血管生长因子表达的影响

目的:探讨塞莱昔布对体外培养的结肠癌细胞生长及肝转移瘤模型血管生长因子(VEGF)表达的影响.方法:以人结肠癌细胞株HT-29,HCT-116为对象,体外药物敏感实验(MTT)法检测塞莱昔布对肿瘤细胞的增殖抑制效应,流式细胞术检测肿瘤细胞各细胞周期分布变化情况,肿瘤细胞接种裸鼠,观察肝转移瘤VEGF表达情况.结果:塞莱昔布对人结肠癌细胞株生长的抑制作用呈时间、剂量依赖性效应,且对HT-29细胞作用强于HCT-116细胞(P<0.01);塞莱昔布可改变结肠癌细胞株细胞周期的分布,明显降低增殖指数(P<0.05).塞莱昔布具有明显的抑制肝转移瘤VEGF表达的作用(P=0.00).结论:塞莱昔布可通过抑制COX-2酶活性而抑制肿瘤细胞的分裂和增殖,诱导其凋亡,并抑制肿瘤血管生成,干预结肠癌的转移与复发.     

巨噬细胞移动抑制因子对结肠癌HT-29细胞增殖和血管生成因子表达的影响

目的研究巨噬细胞移动抑制因子(MIF)在体外对人结肠癌细胞HT-29增殖及VEGF和IL-8表达的影响。方法分别用25、50、100μg/L人重组MIF(rhMIF)对细胞进行处理后,采用MTT法检测细胞增殖,RT-PCR检测细胞VEGF、IL-8mRNA含量,ELISA测定细胞培养上清液中VEGF和IL-8的蛋白含量。结果rhMIF作用不同时间后,能够促进HT-29细胞生长,增殖活性随浓度增加、时间延长逐渐上升(P<0.05),呈现量—效、时—效关系。细胞VEGF和IL-8mRNA表达及上清液中VEGF和IL-8蛋白含量均明显增加,存在时间和浓度依赖性(P<0.05)。结论MIF能够促进结肠癌细胞增殖,MIF参与肿瘤血管形成有可能是通过上调VEGF和IL-8的表达发挥作用。     

青蒿琥酯对人结肠癌HCT-8细胞诱导血管新生的影响及机制探讨

目的观察青蒿琥酯对人结肠癌HCT-8细胞诱导血管新生的影响,并探讨其作用机制。方法采用大鼠主动脉环体外培养实验和鸡胚绒毛尿囊膜体内血管生长实验观察青蒿琥酯对人结肠癌HCT-8细胞诱导血管新生的影响。采用Western blot法检测青蒿琥酯作用前后人结肠癌HCT-8细胞的血管内皮生长因子(VEGF)、血管生成素-2(Ang-2)蛋白。结果青蒿琥酯可明显减少HCT-8细胞诱导的血管生成。HCT-8细胞高表达VEGF、Ang-2蛋白,青蒿琥酯呈剂量依赖方式下调HCT-8细胞VEGF、Ang-2蛋白的表达(P均<0.05)。结论青蒿琥酯具有抗人结肠癌HCT-8细胞诱导血管新生的效应,与青蒿琥酯抑制HCT-8细胞的VEGF、Ang-2蛋白表达有关。     

胃肠安方对瘦素干预后人结肠癌细胞增殖以及VEGF分泌的影响

[目的]观察胃肠安方对瘦素干预后人结肠癌细胞增殖以及VEGF分泌的影响。[方法]体外培养人结肠癌HT-29细胞,建立空白对照组以及模型组,不同浓度胃肠安作用后CCK-8法检测细胞增殖。ELISA试剂盒检测细胞上清液VEGF含量。[结果]胃肠安方对人结肠癌HT-29细胞增殖有抑制作用,可以拮抗瘦素促进人结肠癌HT-29细胞增殖的作用。150 ng/ml leptin能明显促进HT-29细胞分泌VEGF,上清液VEGF浓度为(130.10±1.83)pg/ml,与空白对照组比较差异有统计学意义(P0.05)。1.00 mg/ml、1.75 mg/ml、2.50 mg/ml胃肠安组VEGF浓度为(125.01±1.40)pg/ml,(102.99±1.40)pg/ml,(66.22±1.89)pg/ml,与模型对照组比较,差异有统计学意义,胃肠安方对leptin促HT-29 VEGF分泌的拮抗作用呈剂量依赖性。[结论]胃肠安方能够抑制瘦素刺激的结肠癌HT-29细胞增殖及VEGF分泌。     

尼美舒利抑制结肠癌LOVO细胞增殖及转移的机制

目的 研究选择性COX2抑制剂尼美舒利(Nimesulide)对结肠癌细胞株LOVO生长的影响以及其参与抑制肿瘤血管转移的可能机制.方法 采用四甲基偶氮唑蓝(MTT)比色法观察尼美舒利对结肠癌细胞增殖的抑制,电镜下观察尼美舒利作用后细胞的超微结构变化,ELISA法检测尼美舒利对上清液中血管内皮生长因子(VEGF)的影响.结果 MTT显示尼美舒利能抑制LOVO的增殖,呈剂量和浓度依赖性.0.2 mmol/L尼美舒利作用72 h后电镜观察可见典型的凋亡小体.尼美舒利作用后上清液中VEGF的含量呈剂量依赖性下调.结论 尼美舒利可抑制结肠癌细胞株LOVO的生长,促进其凋亡,还可下调细胞上清中的VEGF含量,推测其通过抑制VEGF释放,从而抑制肿瘤的生长及浸润转移.     

姜黄素对人结肠癌细胞HT-29中β-catenin、血管内皮生长因子的影响

目的研究姜黄素对体外培养人结肠癌HT-29细胞增殖及对细胞株中β-catenin、血管内皮生长因子(VEGF)表达的影响。方法采用不同浓度的姜黄素作用于HT-29细胞,MTT法检测细胞增殖情况;Western印迹检测药物处理后β-catenin及VEGF蛋白的表达。结果姜黄素对HT-29细胞的增殖具有抑制作用,且呈剂量-时间依赖性(P<0.05),测得IC50为19.27μmol/L;在蛋白水平,姜黄素处理后,β-catenin、VEGF的蛋白表达水平降低。结论姜黄素能够抑制HT-29细胞的增殖,并下调结肠癌细胞HT-29中β-catenin、VEGF的表达。     

普伐他汀对人结肠癌细胞增殖及COX-2蛋白表达的影响

目的体外观察普伐他汀对人结肠癌细胞HT-29、Ls-174-T细胞增殖、细胞周期及COX-2蛋白表达的影响。方法采用噻唑蓝（MTT）法观察普伐他汀对HT-29和Ls-174-T细胞增殖的影响，流式细胞仪（FCM）研究普伐他汀对细胞周期的作用，免疫细胞化学观察COX-2蛋白的表达。结果体外普伐他汀可抑制HT-29和Ls-174-T细胞增殖，各处理组内G0／G1期细胞增多，但诱导凋亡不明显，体外普伐他汀可减少HT-29和Ls-174-T细胞株COX-2蛋白的表达。结论体外普伐他汀对HT-29和Ls-174-T细胞增殖有抑制作用，该作用可能与使细胞生长阻滞于G0／G1期及抑制COX-2蛋白表达有关。     

环氧合酶-2抑制剂降低结肠癌细胞血管内皮生长因子表达的影响及机制

目的探讨选择性环氧合酶(COX)-2抑制剂celecoxib影响结肠癌HT-29细胞血管内皮生长因子(VEGF)表达的机制。方法体外培养结肠癌HT-29细胞,采用MTT法检测celecoxib对HT-29细胞增殖的影响。同时针对Sp1和Sp4进行RNA干扰,应用RT-PCR和Western印迹法联合检测celecoxib组和干扰组对HT-29细胞Sp1、Sp4和VEGF m RNA和蛋白表达的影响。结果随着药物浓度的增加(5、10、20、40和80μmol/L)和作用时间的延长(2、4、8、16和32 h),celecoxib对HT-29细胞的增殖具有显著抑制作用,在2、4、8、16和32 h时的半数抑制浓度(IC50)分别为40.36、33.15、31.67、30.94和31.54μmol/L。RT-PCR和Western印迹检测显示,celecoxib可显著降低HT-29细胞Sp1、Sp4和VEGF m RNA和蛋白的表达水平,同时经RNA干扰Sp1(Sp4)后,HT-29细胞Sp1(Sp4)和VEGF m RNA和蛋白的表达水平明显降低,但Sp4(Sp1)m RNA和蛋白表达变化不明显。结论 celecoxib可抑制结肠癌HT-29细胞增殖,其作用机制可能是通过下调Sp1和Sp4表达水平而降低结肠癌细胞中VEGF的表达水平。     

环氧合酶-2抑制剂对结肠癌细胞株的体外研究

目的 观察选择性环氧合酶-2（COX-2）抑制剂对COX-2高表达的结肠癌细胞株HT-29增殖和凋亡的影响，明确以COX2为靶点治疗结肠癌的作用途径以及与COX-2活性、表达水平的相关关系。方法 将选择性COX-2抑制剂NS-398作用于结肠癌细胞系HT29，运用MTT法检测细胞增殖状态。流式细胞仪观察NS-398对细胞凋亡的影响。进一步用逆转录聚合酶链式反应（RT-PCR）检测药物作用前后HT-29中COX-2mRNA表达。ELISA法测定前列腺素E2（PGE2）水平。Western blot检测药物作用前后细胞周期素D1、Bcl-2的表达。结果 结肠癌细胞系HT-29中COX-2 mRNA高表达，NS-398呈时间和剂量依赖性抑制HT-29细胞增殖，促进其凋亡。加入NS-398的HT-29细胞中COX-2mRNA表达水平无明显变化（P〉0．05），PGE2却显著下降（P〈0．01）。72h时空白组与NS-398（75μmol／L）处理组细胞周期素D1、Bcl-2表达水平比值分别为2．21和3．25（P〈0．01），两者表达水平随作用时间延长而下降。结论 选择性COX-2抑制剂NS-398不影响结肠癌细胞COX-2 mRNA表达水平，而与其活性相关（PGE2水平）．可能通过细胞周期素D1、Bcl-2影响结肠癌细胞系HT-29的增殖与凋亡，揭示了COX-2为靶点治疗结肠癌的分子机制。     

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.     

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.     

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.     

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.     

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.