老年2型糖尿病患者血清脂蛋白(a)水平与载脂蛋白(a)基因多态性分析

本文对老年 2型糖尿病患者血清脂蛋白 (a)水平及载脂蛋白 (a)多态性进行了分析 ,以探讨老年糖尿病与高脂蛋白 (a)血症的关系及其载脂蛋白 (a)遗传表型的分布特点 ,同时分析脂蛋白 (a)与糖尿病并发症的相关性。用酶联免疫吸附法测定脂蛋白 (a)水平 ,用十二烷基磺酸钠 -聚丙烯酰胺凝胶电泳和Westernblot技术测定脂蛋白(a)遗传表型。结果发现 :① 3组 (老年 2型糖尿病、非老年 2型糖尿病与老年健康对照组 )脂蛋白 (a)浓度差异无统计学意义 (P >0 .0 5 ) ,脂蛋白 (a)与血清总胆固醇、甘油三酯、高密度脂蛋白胆固醇及其亚型、低密度脂蛋白胆固醇、载脂蛋白A和B水平无相关性 (P >0 .1) ;②老年 2型糖尿病组合并高血压、糖尿病性视网膜病变和糖尿病肾病者的血清脂蛋白 (a)浓度明显高于无合并相应疾病者 (P <0 .0 5或P <0 .0 0 1) ;③ 3组共检出 13种载脂蛋白 (a)基因型 ,在老年 2型糖尿病合并症患者中 ,低分子质量的S1和S2基因型明显多于其它组及无合并症者     

低密度脂蛋白受体基因敲除鼠极低密度脂蛋白和中间密度脂蛋白组分诱导J774巨噬细胞胆固醇酯蓄积

为探讨低密度脂蛋白受体基因敲除鼠血浆极低密度脂蛋白和中间密度脂蛋白组分致动脉粥样硬化的作用,采用密度梯度超速离心法从低密度脂蛋白受体基因除鼠血浆分离极低密度脂蛋白和中间密度脂蛋白组分,用日立７４５０自动分析仪测定其脂含量,琼类糖凝胶电泳和聚丙烯酰胺凝胶电泳测定其电泳迁移率和载脂与鼠腹腔巨噬细胞共同孵育,观察它与巨噬细胞的相互作用。结果发现,低密度脂蛋白受体基因扈除鼠血浆极低密度脂收白和中间密度脂收     

临床血脂测定的方法学与标准化进展

众多研究表明,血脂测定不仅对于高脂血症的诊断及冠心病的危险评估和防治具有重要意义,而且已经应用于其他诸多临床相关专业疾病的研究[1,2]。中华医学会检验分会针对临床血清总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDLC)、低密脂蛋白胆固醇(LDLC)、载脂蛋白AⅠ和B(apoAⅠ和apoB)和脂蛋白(a)[Lp(a)]的测定方法与临床应用等实际工作中出现的问题,制定发表了《关于临床血脂测定的建议》文件[3],对于进一步规范我国临床血脂测定工作,保证测定结果的准确性与合理应用有着重要意义。近年来,临床血脂测定的方法学与标准化是血脂…     

住院2型糖尿病患者血清脂蛋白(a)水平及与糖尿病肾病的关系

目的 研究2型糖尿病患者血清脂蛋白(a)水平的变化,探讨其与糖尿病肾病的关系.方法 2007年1月至2008年11月我院内分泌代谢科收治的2型糖尿病患者1238例,年龄15～89岁,记录血压、体质量及病程,入院第2天测定卒腹及餐后2 h血糖、血脂谱、肾功能及尿白蛋白排泄率,应用肾脏病膳食改良试验公式计算肾小球滤过率.分别根据患者年龄、尿白蛋白排泄率及脂蛋白(a)水平进行分层.采用t检验、方差分析、多元逐步回归分析等进行统计学分析.结果 不同年龄组患者血清脂蛋白(a)水平差异无统计学意义(F=1.144,P>0.05).大量蛋白尿组血清脂蛋白(a)水平显著高于正常蛋白尿组和微量蛋白尿组(F=4.113,P<0.05).研究队列按照血清脂蛋白(a)的四分位点分为四组,随着血清脂蛋白(a)水平的升高,尿白蛋白排泄率逐渐升高(F=7.877,P<0.01),而肾小球滤过率逐渐降低(F=4.479,P<0.01).血清脂蛋白(a)与血清总胆固醇、低密度脂蛋白胆固醇、尿白蛋白排泄率呈正相关(r值分别为0.152、0.169、0.18,均P<0.01),与肾小球滤过率呈负相关(r=-0.061,P<0.01).多元逐步同归分析结果显示:影响尿白蛋白排泄率的主要因素包括收缩压、血清脂蛋白(a)水平、低密度脂蛋白胆固醇、肾小球滤过率、年龄.结论 2型糖尿病患者血清脂蛋白(a)水平不受年龄、病程及血糖控制情况的影响,是尿白蛋白排泄率的独立影响因素.     

不同磷脂配比构成的脂蛋白对J774巨噬细胞胆固醇转运的影响

目的研究不同磷脂配比构成的脂蛋白rHDL-A1、rHDL-A2、rHDL-A3、rHDL-B1、rHDL-B2对J774巨噬细胞胆固醇转运的影响。方法取新鲜抗凝血浆,用超速离心法进行密度梯度离心,收集LDL、HDL3。将LDL置于含10μmol/L CuSO4的PBS溶液(pH7.2)中,37℃温育24h;氧化修饰后的LDL置含200μmol/     

197例不同年龄段、性别、总胆固醇水平“健康体检”者的血浆脂蛋白亚组分水平观察

目的 通过对197例不同年龄段、性别、总胆固醇（TC）水平“健康体检”者的血浆脂蛋白亚组分水平进行对比观察，以总结“健康体检”者血浆脂蛋白亚组分的年龄、性别及TC水平分布特点，为临床降血脂精准用药提供参考。方法 选择197例“健康体检”者，采用全自动生化分析仪检测空腹血清总胆固醇（TC）、高密度脂蛋白胆固醇（HDL-C）和低密度脂蛋白胆固醇（LDL-C）。采用垂直密度梯度离心（VAP）全自动血脂谱检测分离相技术测定空腹血清脂蛋白残粒胆固醇（RLP-C）、中间密度脂蛋白胆固醇（IDL-C）、极低密度脂蛋白3胆固醇（VLDL3-C）、小而密低密度脂蛋白胆固醇（sdLDL-C）、非高密度脂蛋白胆固醇（nonHDL-C）、低密度脂蛋白胆固醇（4+3+2+1）[(LDL(4+3+2+1)-C]脂蛋白a(LPa)、极低密度脂蛋白胆固醇（VLDL-C）、高密度脂蛋白2胆固醇（HDL2-C）和高密度脂蛋白3胆固醇（HDL3-C）。比较不同年龄、性别“健康体检”者血脂亚组分水平。根据TC水平将197例“健康体检”者分为A组（TC<5.2 mmol/L）、B组（TC 5.2～<6.2 mmol...     

高血压病伴代谢综合征其他组分患者血浆脂蛋白(a)水平分析

目的 研究高血压病伴代谢综合征的其他重要组分患者的血浆脂蛋白（a）水平以及临床意义。方法 选择高血压病伴代谢综合征其他重要组分患者100例，以全自动生化仪测定血浆总胆固醇、甘油三酯和脂蛋白（a）值。根据代谢综合征患者伴发代谢紊乱的组分数目分组，对组间患者的脂蛋白（a）水平进行统计分析。数据用SPSS软件进行统计学处理。结果 高血压病伴代谢综合征其他重要组分患者存在着明显的脂代谢紊乱，脂蛋白（a）水平随着伴发代谢综合征组分数目的增加而明显升高，各组之间脂蛋白（a）水平存在有统计学差异而总胆固醇与甘油三酯水平没有统计学差异。结论 血浆脂蛋白（a）水平与代谢综合征关系密切，可以做为提示高血压病患者存在有代谢综合征其他组分的临床线索。     

Compactin和Mevinolin对血清胆固醇的调节作用

正常机体能通过肝脏和肝外组织细胞表面的受体有效地清除血内胆固醇。这些受体同运载胆固醇的循环脂蛋白相结合,使细胞利用胆固醇。因此,该机制有调节胆固醇进出血流的功能,这种机制的损伤必然导致血清胆固醇升高,动脉粥样硬化将随之发生。人体一半以上的胆固醇是再合成的,含胆固醇脂蛋白合成率和细胞摄取和降解决定了血清胆固醇的高低。胆固醇的生物合成需要有一系列的酶参与,其中3-羟基-3-甲基戍二醛辅酶A(HMACoA)还原酶属于限速酶。所以,降低血清胆固醇药物最恰当的作用点应是HMA-CoA还原酶和脂蛋白受体。当肝脏脂蛋白受体受正常生理调节时,受体的数量可由某些降胆固醇药物的作用而增加。     

脂蛋白对巨噬细胞的作用研究进展

脂蛋白的种类、组成、氧化修饰以及基因突变等影响脂蛋白与巨噬细胞的相互作用.载脂蛋白E基因敲除鼠血浆极低密度和中间密度脂蛋白组分通过一种特异而不依赖载脂蛋白E途径诱导巨噬细胞胆固醇酯蓄积,是体内主要致动脉粥样硬化脂蛋白.低密度脂蛋白受体基因敲除鼠血浆极低密度和中间密度脂蛋白组分也显著诱导巨噬细胞胆固醇酯蓄积.人载脂蛋白AⅠ第235位谷氨酸残基缺失明显降低其促巨噬细胞胆固醇外流能力.人极低密度、低密度、高密度脂蛋白以及脂蛋白(a)等氧化后,不仅诱导巨噬细胞胆固醇酯蓄积,也具有显著促巨噬细胞增殖效应.     

脂蛋白Lp(a)、血浆脂质及其它脂蛋白水平与冠状动脉病变的关系

本文对冠状动脉造影显示出的冠状动脉病变程度进行评分,同时测定血浆脂蛋白Lp(a)(一种胆固醇含量丰富的脂蛋白)、总胆固醇、甘油三酯、低密度脂蛋白胆固醇(LDL胆固醇)、及高密度脂蛋白胆固醇(HDL胆固醇).证实血浆脂蛋白Lp(a)水平可     

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.     

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.     

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.     

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.