二甲亚砜对人表皮的核酸和蛋白质合成的影响

用体外培养的人的伪表皮作为模型，进行药物毒理学作用的研究，观察了二甲亚砜（ＤＭＳＯ）在不同浓度和不同接触时间条件下，对人的伪表皮细胞脱氧核糖核酸（ＤＮＡ）、核糖核酸（ＲＮＡ）和蛋白质合成的影响：随着接触时间的延长，ＤＮＡ、ＲＮＡ和蛋白质合成均受抑制。低浓度条件下（１％），ＤＮＡ、ＲＮＡ和蛋白质合成增加；在１５～５０％浓度下，ＤＮＡ和蛋白质合成抑制，而ＲＮＡ合成仍增加；在高浓度条件下（７０％～１００％），ＤＮＡ、ＲＮＡ和蛋白质合成均明显抑制。     

Reduced Expression of nm23 Is Associated with Metastasis of Human Gastric Carcinomas

Reduced expression of nm23 gene is implicated in high metastatic potential In a variety of malignancies. To elucidate the role of nm23 in human gastric carcinomas, we examined loss of heterozygosity (LOH) of nm23 gene by Southern blotting, nm23 mRNA expression by Northern blotting and nm23 protein expression by Western blotting as well as immunohistochemistry in both primary and metastatic tumors. LOH of nm23 gene was found in 2 (8%) out of the 23 informative gastric carcinomas. Twenty-two (84%) out of the 26 cases expressed nm23 mRNA at higher levels in primary tumor tissue than in corresponding non-neoplastic mucosa. No obvious correlation was observed between clinico-pathological features and LOH of nm23 gene or nm23 mRNA expression. On the other hand, 52% of the gastric carcinomas showed reduction of nm23 immunoreactivity in the metastatic tumor of regional lymph nodes, as compared to the primary tumor. Interestingly, 71% of the gastric carcinomas showed weaker nm23 immunoreactivity in the liver metastasis than in the primary tumor. These results suggest that nm23 overexpression is linked with development of gastric carcinomas and the decrease in expression of nm23 participates in metastasis.     

重组O-GLcNAc糖基转移酶在昆虫细胞中的表达和纯化

蛋白质的 O- Glc NAc糖基化修饰是一种细胞核蛋白与细胞浆蛋白的蛋白质翻译后修饰。不同于膜蛋白和分泌蛋白的糖基化修饰 ,与蛋白质磷酸化修饰相似。催化蛋白质 O- Glc NAc糖基转移酶 ( OGT)已被克隆。用Hi5昆虫细胞系统表达并纯化了具有活性的重组 OGT。在 Hi5昆虫细胞中表达的鼠肝 OGT带有一 His 6标记片段。经镍离子螯合柱纯化后 ,其比活性达到 0 .88nmol· min- 1·m g- 1 OGT。因此本研究为进一步研究蛋白 O- Glc NAc糖基化修饰提供重要资源     

心脏机械膜瓣置换术后血浆蛋白C和蛋白S活性变化及其与INR的关系

目的:探讨机械瓣膜置换术后口服华法令抗凝的患者血浆蛋白C(PC)、蛋白S(PS)活性改变的意义及其与国际标准IL比值(INR)的关系。方法:动态监测15例心脏机械瓣膜置换术后口服抗凝药初期患者服药1-2 d、3~10 d及1个月的PC、PS活性及INR值。结果:患者组PC、PS活性低于正常对照组(P<0.05),特别是术后3-10 d PC、PS活性明显低于正常对照组(P<0.01),已下降到正常的50％左右,而此时INR尚未达到治疗范围,提示口服抗凝药治疗初期在人体凝血功能未下调时,抗凝系统功能已经开始下降,有发生血栓的倾向;并且,随着抗凝强度的增高(INR低于1.5-高于2.5),PC、PS活性明显下降。结论:口服华法令抗凝患者在监测INR的同时,需要进行血浆PC、PS活性监测,以更好地预防血栓的发生。     

鞘内注射吗啡对切口疼痛大鼠脊髓背角蛋白激酶Cγ免疫反应的影响

目的 研究鞘内注射吗啡对切口疼痛大鼠脊髓背角蛋白激酶Cγ(PKCγ)免疫反应的影响。方法 SD雄性大鼠24只,随机分为4组(每组6只):假手术组(Ⅰ组)、对照组(Ⅱ组)术前30 min鞘内注射人工脑脊液20μl,术后吗啡治疗组(Ⅲ组)、术前吗啡治疗组(Ⅳ组)分别于术后和术前30min鞘内注射吗啡5μg(10 μl)。所有大鼠均按Brennan法制成切口疼痛模型,用免疫组织化学方法观察脊髓背角PKCγ的表达。结果 Ⅱ组术侧脊髓背角PKCγ-IR表达高于非术侧及Ⅰ组(P<0.01)。与Ⅱ组比较,Ⅲ组、Ⅳ组脊髓背角PKCγ-IR表达降低(P<0.05或0.01),而Ⅲ组、Ⅳ组比较差异无显著性。结论 在大鼠切口疼痛模型中,鞘内注射吗啡的镇痛作用可能与抑制脊髓背角的PKCγ-IR免疫反应有关。     

Decreased expression of DMPK: correlation with CTG repeat expansion and fibre type composition in myotonic dystrophy type 1

Abstract Myotonic dystrophy type 1 (DM1) is an autosomal dominant disease caused by a trinucleotide repeatexpansion, cytosine-thymine-guanine (CTG)_n, in the 3′ untranslated region of a gene encoding the myotonic dystrophy protein kinase (DMPK). To correlate CTG expansion and protein expression, we studied muscle specimens from 16 adult DM1 patients using three anti-DMPK antibodies for immunoblotting. We estimated the amount of the full-length DMPK (85 kDa) in muscle biopsies from normal controls and from DM1 patients carrying different (CTG)_n expansions. We found that DMPK concentration was decreased to about 50% in DM patients’ muscles; the protein decrease did not seem correlated with the CTG repeat length. However, the fibre type composition in skeletal muscle seemed somehow to affect DMPK decrease, as the lowest level of the enzyme was found in patients with the lowest content of type 1 fibre.     

Effects of chelating agents on the rheological property of cervical mucus

As an ongoing effort to elucidate the mechanisms involved in the calcium-dependent fertility regulation process, the viscoelastic properties of the mucus obtained from lamb cervix and human semen, as well as their water and total protein contents after exposure to EDTA, a chelating agent, or Nonoxynol-9 (N-9), a spermicidal agent, were examined. The viscosity was measured using a Cone Plate Digital Viscometer, while the water and total protein contents were determined by the lyophilization process and the Lowry method, respectively. The significant changes in the rheological properties of mucus, such as its viscosity and the water content, upon exposure to EDTA were demonstrated. The viscosity of cervical mucus and human semen were significantly increased by EDTA treatment (as compared to the controls): lamb cervical mucus (2.9 ± 0.3 vs. 2.2 ± 0.3 cps) and human semen (5.0 ± 0.3 vs. 4.3 ± 0.3 cps), respectively. The hydration rate was decreased by EDTA treatment as compared with the control (93.6 ± 0.7 vs. 96.8 ± 0.8%). Among tested samples, the reduction in the percentage of sperm penetration through the cervical mucus was the highest in the mucus containing EDTA, which had the lowest water content (93.6 ± 0.7%), indicating that there is a positive relationship between the hydration rate of the cervical mucus and its ability to permit the penetration of spermatozoa. This result indicates that spermicidal activity exerted by high concentrations of EDTA is in part due to its effect on the rheological properties of cervical mucus or semen.     

蛋白激酶C在软脂酸诱导HepG2细胞胰岛素抵抗中的作用

目的从蛋白激酶C(PKC)信号通路角度,探讨游离脂肪酸(FFA)引起肝脏胰岛素抵抗(IR)的可能机制。方法培养HepG2细胞,同时设立对照组、软脂酸(PA)组、高胰岛素组。软脂酸组、高胰岛素组分别用250μmol/L PA、5×10-7mol/L胰岛素处理24h。然后对照组、软脂酸组再根据胰岛素刺激前加( )与不加(-)PKC抑制剂白屈菜红碱盐酸盐(chelerythrine chloride,CC)5μmol/L预处理1h,随机分为两亚组:对照组(-)、对照组( )、PA组(-)、PA组( )。葡萄糖氧化酶法测定胰岛素刺激后12h葡萄糖消耗量,蒽酮法测定胰岛素刺激后3h点细胞内糖原含量,Western blotting技术检测15min点细胞内P-Ser473PKB、P-Ser21/9GSK-3α/β水平。结果PA组(-)与高胰岛素组葡萄糖消耗量无统计学差异(P=0.523)。葡萄糖消耗量、细胞内糖原含量、P-Ser473PKB、P-Ser21GSK-3α、P-Ser9GSK-3β水平均显示,PA组(-)与对照组(-)比较显著降低(P值依次为0.000,0.000,0.004,0.004,0.028),对照组( )与对照组(-)比较略有升高但无显著性差异;PA组( )与PA组(-)比较显著升高(P值依次为0.000,0.014,0.043,0.041,0.035)。结论PA(250μmol/L)体外成功诱导了HepG2细胞产生IR,PKC信号通路在FFA引起肝脏IR中起着重要作用。     

Does dye laser treatment with higher fluences in combination with cold air cooling improve the results of port‐wine stains?

BACKGROUND AND OBJECTIVE: The use of cold air cooling (CAC) and cryogen spray cooling during dye laser treatment of port-wine stains (PWS) has become a standard in recent years. Still unsolved is the question of which fluences are necessary in combination with CAC in order to achieve an optimum clearance and the lowest possible rate of side-effects. STUDY DESIGN: In a prospective study, we treated 11 patients with PWS with pulsed dye laser (Photogenica V, Cynosure, lambda = 585 nm, iota(p) = 0.5 ms, spot size = 7 mm). Each PWS was partitioned into three areas: (area 1) 6 J/cm(2) without CAC, (area 2) 6 J/cm(2) with CAC (level 4), (area 3) 9 J/cm(2) with CAC (level 4). RESULTS: Area 3 (mean, 59%) showed a slightly better clearance than area 1 (mean, 57%); in area 2, we observed a reduced clearance (mean, 45%). Compared with area 1, we achieved a reduction of pain through CAC in areas 2 and 3. The healing periods as well as the rate of side-effects were comparable in all areas. CONCLUSION: We observed a slight but not statistically relevant increase in clearance with the use of higher fluences and CAC compared with lower fluences without CAC. Because pain is lowered significantly when using CAC, and because this makes the treatment more comfortable for the patients, we tend to recommend the use of higher fluences (9 J/cm(2)) with simultaneous CAC for treating PWS.     

转移相关基因nm23和P53及S100A4在晚期胃癌中的表达及与侵袭转移的相关性研究

目的探讨转移相关蛋白（nm23和P53及S100A4）在晚期胃癌转移发展过程中的意义。方法应用组织芯片和免疫组织化学方法研究nm23、P53和S100A4在74例胃癌患者的癌、癌旁、淋巴结转移、远处转移（肝脏、胰腺、卵巢等）组织中的表达。结果同癌旁组织相比，癌组织中P53和S100A4表达明显升高（P〈0．01），而nm23的表达明显降低（P〈0．05）；同癌组织相比，淋巴结中nm23的表达明显降低（P〈0．05）。远处转移组织S100A4表达明显升高（P〈0．01）。3者的阳性表达与胃癌的部分恶性生物学行为有关。癌组织中nm23^＋／P53^＋、P53^＋／S100A4^＋和nm23^＋／S100A4^＋的基因表型比例分别为48例（64．9％）、50例（67．6％）和39例（52．7％），其中P53^＋／S100A4^＋、nm23^＋／S100A4^＋和nm23^＋／P53^＋／S100A4^＋均与胃癌的高转移潜能相关。结论nm23和S100A4在肿瘤转移中发挥了重要作用；联合检测nm23、P53和S100A4的表达可用于评定胃癌的转移潜能。