细胞内活性氧在糖基化终末产物促人腹膜间皮细胞分泌血管内皮生长因子中的作用

目的:观察糖基化终末产物(AGEs)对人腹膜间皮细胞(HPMC)分泌血管内皮生长因子(VEGF)的影响及细胞内活性氧(ROS)在其中的作用。方法:分别用不同浓度的AGE-HSA及抗氧化剂N-酰-L-半胱氨酸(NAC)作用于细胞,用RT-PCR和ELISA方法测定HPMC中VEGF的表达;再以氧化敏感的荧光染料2、7-二氢二氯荧光素(DCFH)染色,流式细胞仪测定细胞内活性氧强度。结果:AGE-HSA能使细胞内ROS水平明显升高,呈现浓度依赖效应;AGE-HSA同时以时效和量效方式促进HPMC中VEGF的表达;而NAC能够明显抑制AGE-HSA所导致的细胞内ROS升高,同时抑制HPMC中VEGF的分泌。结论:AGE-HSA可能部分通过诱导细胞内ROS,促进HPMC表达VEGF,从而引起腹膜新生血管的增加,最终导致腹膜失超滤现象。     

活血通腑方含药血清对大鼠腹膜间皮细胞增殖的作用

目的观察活血通腑方含药血清干预体外培养大鼠腹膜间皮细胞增殖的效果,初筛对大鼠腹膜间皮细胞增殖能力有影响的最佳药物剂量和时间。方法采用腹腔注射胰酶消化的方式建立RPMC细胞模型,运用血清药理学方法制备不同剂量的活血通腑方含药血清,细胞培养经鉴定成功后分组(空白组、空白血清组、活血通腑方低剂量组、活血通腑方中剂量组、活血通腑方高剂量组),应用MTT法检测活血通腑方含药血清对大鼠腹膜间皮细胞的作用。结果与空白血清组比较,活血通腑方中剂量组含药血清可显著促进RPMC细胞增殖,作用时间在36 h时最为显著。结论活血通腑方含药血清具有诱导大鼠腹膜间皮细胞增殖的作用。     

细胞内活性氧在甲基乙二醛促人腹膜间皮细胞分泌血管内皮生长因子中的作用

目的：观察葡萄糖降解产物甲基乙二醛（MGO）对人腹膜间皮细胞（HPMC）分泌血管内皮生长因子（VEGF）的影响及细胞内活性氧（ROS）在其中的作用。方法：分别用不同浓度的MGO及抗氧化剂N-酰-L-半胱氨酸（NAC）作用于细胞，用RT-PCR和ELISA方法测定HPMC中VEGF的表达；再以氧化敏感的荧光染料2、7-二氢二氯荧光素（DCFH）染色，流式细胞仪测定细胞内ROS强度。结果：MGO能使细胞内ROS水平明显升高，呈浓度依赖效应；MGO同时以时效和量效方式促进HPMC中VEGF的表达；而NAC能够明显抑制MGO导致的细胞内ROS升高，同时抑制HPMC中VEGF的分泌。结论：MGO可能部分通过诱导细胞内ROS，促进HPMC表达VEGF，从而引起腹膜新生血管的增加，最终导致腹膜失超滤现象。     

环氧化酶-2抑制剂对人腹膜间皮细胞转化生长因子-β1表达的影响

目的:研究环氧化酶-2(COX-2)抑制剂对人腹膜间皮细胞(HPMC)转化生长因子-1(TGF-1)表达的影响。 方法:采用胰蛋白酶消化法从人腹膜组织中分离间皮细胞,建立稳定的体外培养模型。用COX-2抑制剂干预高糖(4.25%D-葡萄糖)和细菌脂多糖(LPS)刺激下的HPMC。采用逆转录多聚酶链式反应(RT-PCR)半定量分析HPMC中TGF-1 mRNA的表达。采用双抗夹心法酶联免疫吸附实验检测HPMC培养液中TGF-1蛋白质水平。 结果:HPMC在高糖和LPS的刺激下可明显上调TGF-1的表达(P<0.01),COX-2抑制剂干预组(20nmol/L,40nmol/L, 60nmol/L)明显下调TGF-1的表达(P<0.05)。 结论:COX-2抑制剂能够明显抑制在高糖和LPS的刺激下的HPMC TGF-1的基因表达,为临床用COX-2抑制剂防治腹膜透析患者的腹膜纤维化提供实验和理论依据。     

腹膜透析液对小鼠腹膜间皮细胞超微结构影响的比较研究

作者通过模拟ＣＡＰＤ动物实验，应用扫描电镜观察比较了不同的腹透液对正常小鼠腹膜超微结构的影响，实验结果发现，随着注药时间延长，实验小鼠腹膜间皮细胞游离面微绒毛与间皮细胞的损害逐渐加重；三组腹透液对腹膜间皮影响是不相同的，Ｂａｘｔｅｒ腹透液对腹膜间皮损伤较严重，其中又以醋酸盐腹膜液为甚，注药后２１ｄ，乳酸盐和醋酸盐组均可见轻至中度的纤维素性粘连形成，停止注药后１０ｄ，腹膜间皮损伤基本恢复正常。本文结     

体外转化生长因子—β1与表皮生长因子对人前列腺上皮细胞增作用调节

目的：体外观转化生长因子－β1(TGF-β1）、表皮生长因子（EGF）对前列腺上皮细胞增殖的调节作用。方法：胶原酶消化组织,建立原代前列腺上皮细胞系,细胞培养于无血清培养基中。前列腺特异抗原（PSA）、Pan-Keratin等免疫组织化学染色鉴定培养细胞。给制细胞生长曲线和运用细胞增殖ELISA染色（BrdU)方法观察传代后细胞的生长状况及不同剂量的生长因子TGF-β1、EGF对细胞增殖的作用。结果：培养细胞具有典型的上皮细胞形态特征,PSA、Pan-Keratin染色阳性,细胞传代5－7次开始衰退。不同培养基条件可明显地影响细胞生长活性。EGF促进细胞增殖活性,TGF-β1则抑制增殖,其作用与剂量成正比。此外,EGF与TGF-β1相经减弱对方的作用。结论：体外培养的人前列腺上皮细胞增殖受生长因子TGF-β1和EGF调节,结果提示TGF-β1、EGF可能在前列腺增生（BPH）发病中起重要作用。     

糖皮质激素对老年鼻息肉患者表皮生长因子和表皮生长因子受体的表达影响及其临床作用

目的探讨糖皮质激素治疗老年鼻息肉患者的效果及其对息肉组织中表皮生长因子(EGF)和表皮生长因子受体(EGFR)表达水平的影响。方法纳入2014年1月至2016年8月在我院接受糖皮质激素治疗的60例老年鼻息肉患者(息肉组)及鼻中隔偏曲患者20例(对照组)。息肉组患者采用布地奈德喷剂治疗12周,分别于治疗前、治疗后采集息肉组织及对照组鼻黏膜组织进行免疫组化染色及逆转录-多聚酶链反应(RT-PCR)检查,对比两组EGF和EGFR蛋白及信使核糖核酸(mRNA)表达水平。计量资料以均数±标准差表示,两组间比较采用t检验。结果息肉组患者的鼻息肉病变评分情况:治疗前(2.48±0.77)分,治疗2周后(2.11±0.68)分,治疗6周后(1.57±0.49)分,治疗12周后(1.29±0.64)分;鼻息肉病变评分呈逐渐降低趋势,各时间点比较差异具有统计学意义(P0.05)。息肉组在治疗前、治疗后的EGF、EGFR蛋白表达水平和mRNA表达水平均高于对照组(P0.05);息肉组治疗12周后鼻息肉组织中EGF和EGFR蛋白表达水平和mRNA表达水平较治疗前均显著降低(P0.05)。结论糖皮质激素治疗老年鼻息肉患者的效果肯定,其作用机制与抑制鼻息肉组织中EGF及EGFR表达有关。     

表皮生长因子与肝癌

表皮生长子与肝癌的发生与发展有着密切的关系,对其作用机制的研究,可为肝癌的防治提供新的途径。     

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.     

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.     

Variabilité des concentrations plasmatiques de l’angiotensinogène et risque d’hypertension artérielle chez le rat transgénique

Aim

Genetic polymorphisms of the human angiotensinogen gene are frequent and may induce up to 30% increase of plasma angiotensinogen concentrations with a blood pressure increase of up to 5 mmHg. Their role for the pathogenesis of human arterial hypertension remains unclear. High plasma angiotensinogen levels could increase the sensitivity to other blood pressure stressors.

Methods

Male transgenic rats with a 9-fold increase of plasma angiotensinogen concentrations and male non-transgenic rats aged 10 weeks were treated or not with NG-Nitro-L-arginine-methyl ester for 3 weeks in their drinking water (n = 3/group). Systolic blood pressure and body weight were measured at baseline and at the end of the study when left ventricular weight and ventricular expression of angiotensin I-converting enzyme and procollagen Iα1 were determined (polymerase chain reaction).

Results

At baseline, transgenic rats had +18 mmHg higher bood pressure and –8% lower body weight compared to non-transgenic rats (P < 0.05) without significant changes for the vehicle groups throughout the study (P > 0.05). NG-Nitro-L-arginine-methyl ester increased blood pressure, left ventricular weight and left ventricular weight indexed for body weight by +41%, +17.6% and +18.6% (P < 0.05) in transgenic and +25%, +5.3% and +6.7% (P > 0.05) in non-transgenic rats compared to untreated animals, respectively. Cardiac gene expression showed no differences between groups (P > 0.05).

Conclusion

Increased plasma angiotensinogen levels may sensitize to additional blood pressure stressors. Our preliminary results point towards an independent role of angiotensinogen in the pathogenesis of human hypertension and associated end-organ damage.     

Morphological and immunocytochemical heterogeneity of cultured pinealocytes from one-week-and two-month-old rats: Planimetric and densitometric investigations

Abstract: In vitro preparations of rat pinealocytes are widely used for biochemical analyses of signal transduction processes. This paper deals with morphological and immunocytochemical features of such preparations. Special attention was paid to the problems of whether pinealocytes represent a heterogeneous cell population and how such heterogeneity may develop during ontogeny. The investigations were performed with cells which were obtained from the pineal organ of one-week-and two-month-old rats, attached to synthetic peptide-coated coverslips or tissue culture chamber slides, and maintained under in vitro conditions overnight. The attached cells were then fixed with paraformaldehyde. These preparations yielded monolayers of spherical cells of different sizes; most cells were isolated, but some of them were aggregated and formed small clusters. On the average, the cells from the one-week-old animals were smaller than the cells from the two-month-old animals. Immunocytochemical demonstration of S-antigen, a pinealocyte-specific marker, showed that the majority of the cells from two-month-old animals were intensely or moderately labelled. Pinealocytes from one-week-old animals were less S-antigen immunoreactive. Only very few cells (less than 1% displayed glial fibrillary acidic protein (GFAP)-immunoreactivity. Planimetric investigations of the cell size and semiquantitative densitometric investigations of the intensity of the S-antigen immunoreaction revealed that (i) pinealocytes kept in vitro form a heterogeneous cell population, and that (ii) this heterogeneity increases during postnatal development from one-week-old to two-month-old animals. Two groups of pinealocytes can be distinguished based on their developmental fate: pinealocytes of one group grow dramatically, but show only a moderate increase in S-antigen immunoreactivity, and pinealocytes of the other group retain their size, but display a distinct increment in S-antigen immunoreacti vitv.     

Effects of pinealectomy and melatonin administration on certain indices of ovarian hyperplasia and/or hypertrophy in rats with both ovaries intact or after unilateral ovariectomy

Abstract: In earlier studies from other laboratories it was shown that melatonin decreased ovarian weight in rats and inhibited compensatory hypertrophy of the remaining ovary after unilateral ovariectomy. This study was designed to examine the influence of melatonin on certain indices of ovarian hyperplasia and/or hypertrophy in adult female rats with both ovaries preserved and with either an intact pineal gland or with the pineal gland removed (pinealectomy, PX) or, finally, in sham-PX animals. Similar studies were conducted on rats after unilateral ovariectomy, referring the examined parameters to the remaining intact ovary. The studies included mitotic activity of granulosa layer cells and corpus luteum cells, ovarian weight, ovarian cross-sectional area, cross-sectional area of the granulosa layer of all the Graafian follicles and the cross-sectional areas of the corpora lutea, visible on the ovarian cross-section. On the basis of results, we conclude that: 1) the effect of PX on the processes of ovarian hyperplasia and hypertrophy may vary; analogously, exogenous melatonin administration may influence ovarian hyperplasia and hypertrophy in different ways; 2) PX and exogenous melatonin may, under certain conditions, exert similar biological effects, even synergistic effects; 3) melatonin inhibits ovarian growth processes, while the effects of PX are variable; 4) the results indicate that in experiments performed on rats, with the use of two control groups, i.e., intact and sham-PX, melatonin effects on these two groups may differ.