氧自由基动态变化与胆红素结石成石的实验研究

用胆红素结石（ｐｓ）兔模型进行实验，设单纯胆道梗阻（ＢＯ）组、梗阻和大肠杆茵感染（ＢＯＩ）组及空白对照组，观察肝组织及胆汁氧自由基（ＯＦＲ）变化情况及对ＰＳ的影响。实验结果：肝组织部分ＯＦＲ、前列腺素Ｅ＿２（ＲＧＥ＿２）及ＰＳ的动态变化趋势相似，三者呈正相关；ＢＯＩ组的上述指标均较ＢＯ组为高。提示ＯＦＲ可能促使ＰＧＥ＿２合成，后者致糖蛋白分泌而参与ＰＳ的形成；大肠杆菌感染可能在梗阻的基础上增多ＯＦＲ的生成而增加了Ｐｓ的形成。     

Altered impedance during pigment aggregation in<Emphasis Type="Italic">Xenopus laevis</Emphasis> melanophores

Melanophores are dark-brown pigment cells located in the skin of amphibia, fish and many invertebrates. The skin colour of these organisms is regulated by the translocation of pigment organelles, and the pigment distribution can be altered by external stimuli. The ability to change colour in response to stimuli makes these cells of interest for biosensing applications. It was investigated whether pigment aggregation in Xenopus laevis melanophores can be detected by impedance measurements performed in transparent microvials. The results show that cell attachment, cell spreading and pigment aggregation all resulted in impedance changes, seen particularly at the highest frequency tested (10 kHz). The mechanisms behind the impedance changes were investigated by the addition of latrunculin or melatonin, both of which cause pigment aggregation. The latrunculin-induced aggregation was associated with cell area decrease and filamentous actin (F-actin) breakdown, processes that can influence the impedance. Lack of F-actin breakdown and an increase in cell area during melatonin-induced aggregation suggest that some other intracellular process also contributes to the impedance decrease seen for melatonin. It was shown that impedance measurements reflect not only cell attachment and cell spreading, but also intracellular events.     

视细胞移植术后视网膜色素上皮的结构变化

获得纯化的由大肠杆菌表达的小鼠 Ｆａｓ配体（Ｆａｓ ｌｉｇａｎｄ,ＦａｓＬ）。方法：以质粒 ｐＥＴ－１５ｂ为载体,在大肠杆菌ＢＬ２１（ＤＥ３）中表达小鼠的ＦａｓＬ,用金属螫合亲和层析法纯化。结果：转化菌中,重组质粒是稳定的,异丙基－β－Ｄ硫代半乳糖苷可诱导小鼠ＦａｓＬ的表达 ,金属螫合亲和层析法可以初步纯化此蛋白。结论：在大肠杆菌中表达出小鼠的ＦａｓＬ,并得到初步纯化。     

米团花色素的提取及其稳定性研究

米团花色素是云南省某些地区居民使用的一种传统黄色天然食用色素.本研究表明,米团花色素在433 nm和326 nm处分别有一个较强吸收峰.稳定性实验表明:该色素对酸、热、光、氧化剂过氧化氢(不加热)、常见金属离子、食盐及食糖等稳定,但在碱性条件或亚硫酸钠存在时不太稳定.此外,加入过氧化氢后加热也会引起其吸光值的显著改变.初步确定米团花色素主要为胺类物质.在正常加工条件下,是一种较理想的天然食用色素.     

色素上皮衍生因子抑制高糖诱导的人肾小球系膜细胞转化生长因子β1、纤连蛋白和Ⅳ型胶原的表达

随着葡萄糖浓度的增加,人肾小球系膜细胞转化生长因子β1(TGF-β1)、纤连蛋白(FN)和Ⅳ型胶原(ColⅣ)的表达显著增加(P＜0.01).在30 mmol/L的高糖条件下,40～160 nmol/L的色素上皮衍生因子(PEDF)显著抑制TGF-β1表达,呈剂量依赖性(P＜0.01);5～40 nmol/L的PEDF也剂量依赖性地抑制FN和ColⅣ的表达(P＜0.01),提示PEDF可能通过其抗纤维化的作用延缓糖尿病肾病的进程.

Abstract：

The expressions of transforming growth factor β1 (TGF-β1), fibronectin (FN), and collagen Ⅳ in human mesangial cells were augmented with increased concentrations of glucose.Pigment epithelium-derived factor (PEDF) at concentrations of 40-160 nmol/L significantly inhibited TGF-β1 expression in a dose-dependent manner(P＜0.01).PEDF at concentrations of 5-40 nmol/L significantly decreased FN and collagen Ⅳ expressions in a dose-dependent manner(P＜0.01) ,suggesting that PEDF may play a salutary role in diabetic nephropathy by its antifibrogenic activity.     

MicroRNA-93 promotes bladder cancer proliferation and invasion by targeting PEDF

Objective

MicroRNA-93 (miR-93) is upregulated in the urine of patients with bladder cancer (BC). Here, we investigated the role of miR-93 in BC progression and explored the underlying mechanism.

瑞舒伐他汀对2型糖尿病视网膜病变患者血清PEDF、IL-6水平的影响

目的探讨瑞舒伐他汀对2型糖尿病视网膜病变(DR)患者血清PEDF、IL-6水平的影响。方法选取60例2型糖尿病视网膜病变患者,随机分为实验组(瑞舒伐他汀治疗)30例和空白对照组(仅常规降血糖治疗)30例,疗程为3个月。分析两组患者治疗前后血清PEDF、IL-6、TC、TG、LDL、HDL、FPG、2h PG、Hb A1c水平以及DR分期的变化情况。结果实验组血清IL-6、TC、TG、LDL、FPG、2h PG、Hb A1c水平及DR分期与治疗前比较明显下降,血清PEDF、HDL水平与治疗前比较明显升高,差异均有统计学意义(P<0.01)。空白对照组中FPG、2h PG、Hb A1c水平较治疗前明显下降(P<0.01),其余各指标与治疗前比较,差异均无统计学意义(P>0.05)。实验组治疗前后的差值(ΔPEDF、ΔIL-6、ΔDR分期、ΔTC、ΔTG、ΔLDL、ΔHDL)与对照组治疗前后的差值比较,差异均有统计学意义(P<0.01)。结论瑞舒伐他汀能显著降低DR患者血清IL-6水平,升高血清PEDF水平,从而延缓了DR患者的病情进展。     

Phagocytosis of Hemozoin (Native and Synthetic Malaria Pigment), and Plasmodium falciparum Intraerythrocyte-Stage Parasites by Human and Mouse Phagocytes

Hemozoin, the detoxification product of hemoglobin heme, piles up as electron-dense material in the food vacuole (FV) of intraerythrocytic malaria parasites (malaria pigment). In infected individuals, pigment is internalized by both circulating and resident phagocytes, thus modulating their functions. Synthetic beta-hematin, prepared in vitro from hematin (ferriprotoporphyrin IX hydroxide) in acidic condition, is spectroscopically identical to hemozoin. In this electron microscopy study, native and synthetic hemozoin also prove to be morphologically indistinguishable (large polygonal crystals with apparent transverse banding) and to undergo the same process when internalized by phagocytes (primarily a direct uptake of crystals, similar to what is described for asbestos fibers). On the contrary,whole parasites appear to follow a classical endocytic pathway. This suggests that there may be differences between the ingestion of free particles and whole parasites in terms of modulation of phagocytes' functions.     

双氢青蒿素对人骨肉瘤细胞TE85细胞内尿激酶型纤溶酶原激活物和色素上皮衍生因子表达的影响

目的 观察双氢青蒿素(DHA)对人骨肉瘤细胞活性、转移能力以及细胞中尿激酶型纤溶酶原激活物(uPA)和色素上皮衍生因子(PEDF)表达的影响.方法 将不同浓度的DHA(5、10、20、40、80 μmol/L)作用于体外培养的正常人成骨细胞和人骨肉瘤细胞TE85 12、24、48 h后,噻唑蓝(MTT)法测定DHA对细胞活性的影响,反转录-聚合酶链反应(RT-PCR)法检测细胞中uPA和PEDF mRNA水平的表达,Westen blot法检测uPA和PEDF蛋白水平的表达.结果 DHA对人成骨细胞活性无明显影响(P＞0.05).DHA能够明显抑制人骨肉瘤细胞TE85的活性(P＜0.05).不同作用时间下DHA对人骨肉瘤细胞TE85的半数抑制浓度(IC50)分别为(12 h)=(41.66±0.53) μmol/L、IC50(24 h)=(32.28 ±0.27)μmol/L和IC50 (48 h)=(22.53±1.26) μmol/L.DHA能够明显减少人骨肉瘤细胞的迁移和细胞中uPA的表达水平,同时细胞中PEDF表达升高(P＜0.05).结论 DHA对正常人体骨组织无害,能够有效抑制骨肉瘤细胞生长和转移.