SV40LT抗原介导的人源性肝细胞系的构建

目的　建立人源性肝细胞系 ,为生物人工肝和肝细胞移植等提供合适的细胞源。方法　利用SV4 0LTag基因和真核表达载体pcDNA3.1( - )经脂质体转染至来源于 2 5岁男性脑死亡者供肝的原代培养细胞 ,使其永生化 ,进一步鉴定其形态学特征和生物学功能。结果　经G4 1870 0～30 0 μg/ml筛选 ,4 2d后获一抗G4 18肝细胞系。该细胞系呈单层贴壁、上皮细胞样形态生长 ,体外培养可无限传代 ,具有分泌白蛋白 (ALB)、丙氨酸氨基转移酶 (ALT)、天冬氨酸氨基转移酶 (AST)及乳酸脱氢酶 (LDH)的功能 ,超微结构观察发现 ,转染肝细胞具有原代培养肝细胞的大多数典型特征 ,如较大的细胞核、胞浆内含有丰富的糖原颗粒、大量的线粒体和粗面内质网等。经逆转录聚合酶链反应(PCR)和蛋白质印迹检测 ,转染肝细胞的ALBmRNA阳性和细胞色素P4 5 0 2E1阳性。结论　新建人源性肝细胞系与原代培养肝细胞具有类似的形态学特征和生物学功能     

人胎肝细胞培养上清对大鼠肝细胞增殖作用的初步观察

目的观察培养人胎肝细胞分泌上清（ＦＨＣＳ）对培养大鼠肝细胞的影响。方法用相差显微镜动态观察培养大鼠肝细胞的形态变化，并用放免分析法检测其ＤＮＡ合成量。结果ＦＨＣＳ对鼠肝细胞的原代培养有明显作用，表现为大鼠肝细胞增殖活跃、生长旺盛，维持正常形态及存活时间延长，肝细胞ＤＮＡ合成量明显增加（Ｐ＜０．０１）。结论ＦＨＣＳ对体外大鼠肝细胞有明显的增殖刺激作用，该作用可能与分离、培养胎肝细胞过程中分泌产生的多种细胞因子和营养物质有关，并为早期胎肝细胞悬液治疗重型肝炎的可能机理。     

转基因肝星状细胞株对肝细胞生长的支持作用

目的 探讨转基因肝星状细胞株CFSC／HGF对大鼠肝细胞生长的支持作用。方法将大鼠原代肝细胞培养于稳定表达肝细胞生长因子(HGF)的肝星状细胞株CFSC／HGF所构建的饲养层上,连续动态观察肝细胞的形态、超微结构、白蛋白分泌、尿素合成以及吲哚氰绿摄取排泌功能的变化,同时与传统胶原贴壁培养的肝细胞进行比较,并通过半定量逆转录聚合酶链反应(RT-PCR)检测HGF受体c-Met表达的变化。结果共培养的肝细胞体外培养至7～10d时细胞增殖、白蛋白分泌及尿素合成达到峰值,以后逐渐下降,至35d时仍保持一定的存活和功能。与传统胶原上培养的肝细胞相比,其寿命、形态和功能的维持时间明显延长;RT-PCR结果显示,与CFSC／HGF饲养层细胞共培养1周后,肝细胞表面c-Met表达上调2．23倍。结论转基因肝星状细胞株CFSC／HGF对肝细胞较长时间内保持高活性、高密度的生长有显著的支持作用,CFSC／HGF诱导的肝细胞表面c-Met表达上调可能参与了该支持作用。     

大鼠肝纤维化肝细胞的原代培养

本文介绍了建立大鼠二甲基亚硝胺(DMN)肝纤维化模型肝细胞原代培养的方法,经与正常大鼠培养肝细胞之结果相比较,证实前者在细胞的生长、形态、超微结构及胶原代谢等方面均有别于后者。     

肝样细胞模型在药物性肝损伤研究中的进展

肝样细胞由胚胎干细胞、诱导多能干细胞、外周血单核细胞或其他成体细胞等非肝脏来源的细胞在不同诱导培养条件下逐步分化而成, 其形态类似于原代肝细胞, 具备合成、摄取、分泌和药物代谢等功能, 是体外预测和评估药物性肝损伤的理想细胞模型。不同来源的肝样细胞在研究药物代谢和毒性方面各有优缺点, 改进诱导策略和培养体系有助于获得功能更加成熟的肝样细胞。     

大鼠脐带间充质干细胞对肝细胞及卵圆细胞体外增殖与功能的影响

目的：探讨大鼠脐带间充质干细胞（UMSC）对原代大鼠肝细胞及肝卵圆细胞增殖与功能的影响。方法采用2-乙酰氨基芴加肝脏三分之二切除术建立肝卵圆细胞增殖模型,通过原位二步胶原酶灌流法分离到单个肝脏细胞,再经过 Percoll 密度梯度离心分离到肝卵圆细胞。原代大鼠肝细胞/肝卵圆细胞各分为3组：UMSC 组、原代大鼠肝细胞组/肝卵圆细胞组及 UMSC 与原代大鼠肝细胞共培养组/UMSC 与肝卵圆细胞共培养组,分别于第1、3、6、8天通过MTT 法检测各组细胞增殖能力,于第3天通过 ELISA 法检测各组细胞培养上清液中白蛋白含量。结果UMSC 与原代大鼠肝细胞共培养组在第3、6、8天的 A 值均比相应时间点的 UMSC 组 A 值与原代大鼠肝细胞组 A 值之和大（P ＜0．05）;UMSC 与肝卵圆细胞共培养组在第3、6、8、10天的 A 值均比相应时间点的 UMSC 组 A 值与肝卵圆细胞组 A 值之和大（P ＜0．05）。UMSC 无白蛋白分泌能力,UMSC 与原代大鼠肝细胞共培养组培养上清液中白蛋白水平为（266．21±50．44）ng/mL,较原代大鼠肝细胞组（130．79±22．10）ng/mL 高（P ＝0．013）;UMSC 与肝卵圆细胞共培养组培养上清液中白蛋白水平（（49．64±3．56）ng/mL）较肝卵圆细胞组（13．54±1．53）ng/mL 高（P ＝0．000）。结论UMSC 在体外可以促进原代大鼠肝细胞及肝卵圆细胞的存活和增殖,并可增强其分泌白蛋白的作用。     

有效原代猪肝细胞培养体系的研制

目的建立一种有效的原代猪肝细胞长期培养体系．为人工肝生物材料提供生存环境．方法把经二步胶原酶灌注法分离的猪肝细胞按３×１０５分别接种于无血清培养基、１００ｍＬ／Ｌ胎牛血清培养基、１００ｍＬ／Ｌ的猪门静脉血清培养基中．光镜下观察各体系中肝细胞形态变化过程．采用Ｂｅｃｋｍａｎ全自动生化分析仪检测各培养体系不同时间培养上清中Ａｌｂｕｍｉｎ,Ｕｒｅａ的含量．结果原代猪肝细胞在三种不同培养体系中存活时间分别是：无血清培养基４ｄ～５ｄ,胎牛血清培养基３５ｄ～３７ｄ,猪门静脉血清培养基５７ｄ～５８ｄ．存活的肝细胞功能活性除无血清培养组不明显外,胎牛血清培养组可维持４ｗｋ左右,猪门静脉血清培养组则可维持８ｗｋ左右结论门静脉血清培养体系是原代猪肝细胞较为理想的生存环境．     

抗纤复方对硬变肝原代培养肝细胞胶原代谢的影响

本研究通过对原代培养的大鼠肝细胞作用,建立抗纤复方血清药理学方法;通过对原代培养的二甲基亚硝胺(DMN)肝纤维化肝细胞的处理。观察抗纤复方对纤维肝肝细胞生成胶原、纤维连接蛋白、层粘连蛋白等的影响,以探讨抗纤复方抗肝纤维化的作用机理。 1 抗纤复方对大鼠肝细胞生成胶原的影响     

大鼠肝细胞与人脐静脉内皮细胞混合共微囊化的体外研究

目的 观察人脐静脉内皮细胞(HUVECs)对共微囊化大鼠肝实质细胞的保护作用.方法 利用自制微囊发生器制备含肝细胞或肝细胞与HUVECs以10:1混合的微囊进行体外培养,同时建立非微囊化单独培养和共培养组,通过测定培养液中自蛋白、尿素的分泌量和肝细胞形态来判断肝细胞功能和活性.结果 肝细胞与HUVECs共培养或共微囊化均能提高前者的白蛋白分泌和尿素合成量(均P<0.01),存活时间延长;共微囊化组虽前7 d的白蛋白和尿素合成量较非微囊化共培养组低,但在7 d后的白蛋白和尿素合成量高于后者,且相对平稳.结论 肝细胞与HUVECs混合共微囊化能明显改善囊内肝细胞的形态、功能与寿命.     

氟化钠对原代培养大鼠肝细胞的毒性作用及机理研究

目的探讨氟化钠(NaF)对原代培养大鼠肝细胞的毒性作用及其机制.方法采用不同剂量的氟化钠处理原代培养的大鼠肝细胞,观察由此所致的细胞酶学和形态学变化来评价其毒性作用及方式.结果肝细胞存活率呈明显的剂量-效应关系,IC50为3.58 mmol/L;当氟化钠浓度为2 mmol/L时,肝细胞培养液中谷草转氨酶(AST)、谷丙转氨酶(ALT)活性明显增加(P＜0.05);丙二醛(MDA)含量随染氟剂量增加而增加.细胞形态改变包括收缩、变圆、变小.发生这种改变的的细胞占总细胞数的比例随剂量的增加而增加.结论氟化钠对原代培养大鼠肝细胞有明显的毒作用,其主要作用方式之一是引起细胞发生脂质过氧化.     

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.