增殖细胞核抗原在膀胱移行细胞癌中的表达及意义

目的，为探讨膀胱移行细胞中增殖细胞核抗原（ＰＣＮＡ）的表达及意义，方法 采用免疫组化ＬＳＡＢ法，对４４例膀胱移行细胞癌细胞核抗原（ＰＣＮＡ）的表达进行研究，结果膀胱移行细胞癌Ⅲ级ＰＣＮＡ增殖指数明显高于Ｉ＋Ⅱ级（Ｐ〈０．０５）膀胱移行细胞癌临床分期Ｔ３＋Ｔ４中ＰＣＮＡ增殖指数明显高于Ｔ１＋Ｔ２期（Ｐ〈０．０５）。结论 ＰＣＮＡ表达与膀胱移行细胞癌分化程度，临床分期有关，可能是判断膀胱癌预后的重要指     

炎性刺激剂对小鼠腹腔巨噬细胞NF-κB的诱导

目的：建立炎性刺激剂诱导细胞核因子κB（Nuclear factor κB,　NF-κB）的模型，研究传统非甾体抗炎药阿斯匹林（aspirin）作用机理。 方法：用脂多糖（LPS）和佛波酯（PMA）刺激小鼠腹腔巨噬细胞，用电泳迁移率改变检测法（electrophoretic mobility shift assay,EMSA）检测。结果：LPS 1 μg.mL^-1及3 μg.mL^-1，PMA 2 ng.mL^-1均能诱导细胞核内NF-κB的含量。阿斯匹林10-5 mol.L^-1可以显著抑制LPS（1 μg.mL^-1）和PMA（PMA 2 ng.mL^-1）对细胞核内NF-κB的活化。结论：所建立的以LPS和PMA为刺激剂，诱导细胞核内NF-κB的模型，可用于非甾体抗炎药的抗炎机理的研究。     

Imaging of adenosine bolus transit following intravenous administration: insights into antiarrhythmic efficacy

OBJECTIVE: To study the effects of the site of intravenous injection of adenosine and to assess the site of action of adenosine in the heart by correlating cardiac effects with bolus transit. METHODS: Ten patients undergoing routine technetium (Tc-99m) gated blood pool ventriculography consented to the coadministration of intravenous adenosine. The dose of adenosine required to produce heart block during sinus rhythm was determined following antecubital vein administration. This dose (6-18 mg) was mixed with Tc-99m and given first into the same antecubital vein (proximal injection) and then repeated into a hand vein (distal injection). The ECG was recorded and the transit of the bolus was imaged using a gamma camera. RESULTS: Heart block occurred in all 10 patients (second degree in seven, first degree in three) at (mean (SEM)) 17.5 (1.0) seconds after the proximal injection of adenosine. Distal injection produced heart block in six patients (second degree in two, first degree in four) at 21.9 (4.4) seconds (p < 0.01). In eight of 10 patients the electrophysiological effects were less with distal injection. The onset of heart block was close to the time of peak bolus Tc-99m activity in the left ventricle. Peak bolus activity was delayed (by about three seconds) and the duration of bolus activity in the left ventricle was increased with distal injection compared with proximal injection, at 17.2 (4.2) v 9.2 (3.1) seconds, p < 0.01. CONCLUSIONS: The lesser electrophysiological effects of adenosine following distal intravenous injections were associated with delay in transit time and dispersion of the bolus. The correlation of adenosine induced heart block with bolus activity in the left heart indicated dependence on coronary arterial delivery of adenosine to the atrioventricular node.     

Angiotensin-converting enzyme inhibition attenuates renal platelet-derived growth factor gene expression and cell proliferation in subtotal nephrectomy

Cell proliferation, matrix accumulation and cell infiltration are characteristic features of progressive glomerulosclerosis and tubulointerstitial fibrosis. Platelet‐derived growth factor (PDGF), a cytokine which has proliferative, prosclerotic and chemokine properties, has been shown to be upregulated in the rat remnant kidney model. Inhibition of the renin–angiotensin system by angiotensin‐converting enzyme (ACE) inhibitors has a beneficial effect on renal function and morphology, but the effect of ACE inhibition on PDGF gene expression and PDGF‐mediated cellular proliferation in subtotal nephrectomy has not been studied in detail. Twelve rats were subtotally nephrectomized (STNx) and received either the ACE inhibitor perindopril or a placebo for 12 weeks. Five sham‐operated rats served as controls. Subtotal nephrectomy was associated with hypertension, proteinuria, elevated plasma creatinine and increased kidney weight. After 12 weeks, PDGF B‐chain mRNA was significantly upregulated in the glomeruli and tubulointerstitium of subtotally nephrectomized rats. ACE inhibition attenuated PDGF mRNA expression in association with a reduction in tubular and glomerular proliferation, as assessed by staining for proliferating cell nuclear antigen. In the context of the known in vitro and in vivo effects of PDGF, it is postulated that the renoprotective action of ACE inhibitors may be partially related to PDGF‐mediated antiproliferative mechanisms.     

Reduction of orthodontic tooth movement by experimentally induced periodontal inflammation in mice

Orthodontic therapy is known to have an aggravating effect on the progression of destructive periodontitis if oral hygiene is not maintained. However, it is largely unknown how active periodontitis affects the velocity of orthodontic tooth movement. In this study, we examined the effect of periodontal inflammation on orthodontic tooth movement using a mouse model. Orthodontic force was applied on the maxillary first molar of mice, with or without ligature wire to induce experimental periodontitis. The distance moved by the first molar was significantly reduced by the ligature-induced experimental periodontitis. Tartrate-resistant acid phosphatase staining revealed that the number of osteoclasts present during orthodontic treatment was lower in the pressure zone of alveolar bone in the presence of periodontal inflammation. Consistently, the expression level of receptor activator of nuclear factor-κB ligand (RANKL) in the pressure zone was decreased in the ligature group. By contrast, experimental periodontitis increased the expression of cyclooxygenase-2 mRNA in the periodontal tissues, while in vitro treatment with prostaglandin E₂ decreased extracellular signal-regulated kinase phosphorylation and RANKL expression induced by mechanical stress in osteoblasts. Taken together, these results suggest that the orthodontic force-induced osteoclastogenesis in alveolar bone was inhibited by the accompanying periodontal inflammation, at least partly through prostaglandin E₂, resulting in reduced orthodontic tooth movement.     

烟雾吸入伤大鼠肺组织细胞凋亡与增殖的变化

目的　观察大鼠烟雾吸入性损伤后肺组织细胞凋亡、细胞增殖的变化规律 ,探讨肺组织损伤修复过程中细胞凋亡的意义。　方法　制作大鼠烟雾吸入性损伤模型 ,随机分为正常对照组、烟雾致伤组 ,应用TUNEL技术及免疫组化技术 ,观察伤后各时相点肺组织细胞凋亡指数及增殖细胞核抗原指数的变化。　结果　 (1)烟雾吸入伤后细胞凋亡指数在伤后 2h增加并维持在高平台区。 (2 )增殖细胞核抗原指数在伤后 12h开始升高 ,3d时达到高峰 ,以后保持在较高水平。　结论　细胞凋亡不仅参与了烟雾吸入伤的早期肺损害 ,也参与了后期修复中增生组织的修饰改建     

凝胶阻滞检测核蛋白-DNA结合方法的探讨

目的：探讨改良的凝胶阻滞法用于核蛋白-DNA结合的检测。方法：培养人真皮成纤维细胞，用维甲酸刺激不同时段，抽提其核蛋白，与32P-标记维甲酸反应元件（RARE）及维甲类X受体α、β（RXRα、β）抗体结合，进行凝胶阻滞分析。结果：细胞于不同状态可出现迁移率不同的条带，加入RXRβ抗体可产生新的上移条带。结论：改良后的凝胶阻滞法较简单灵敏，可用于核蛋白-DNA结合的检测。     

煤加氢液化和苯加压萃取所得沥青质组成结构的研究

借助~1H-NMR、IR、分子量测定和元素分析,采用Brown-Ladner方法,研究了煤加氢沥青质(Ⅰ)和苯加压萃取沥青质(Ⅱ)的组成结构,计算了碳原子分布、芳香度、芳环和脂环数等结构参数,推测了它们的化学结构模型,并与煤的化学结构模型进行了比较。Ⅰ随反应温度增加,芳香度急剧提高。390℃、430℃和470℃时,其芳香度分别为0.78、0.85和0.91,说明在高温下发生了脱氢反应。Ⅱ的芳香度随煤的变质程度增加而提高,其组成结构与煤本体没有根本的差别,是分散在高分子结构中的低分子化合物。