Isolation of a rat S100 alpha cDNA and distribution of its mRNA in rat tissues.

In order to clarify the reported discrepancies in S100 alpha protein and mRNA distribution in rat tissues, a rat S100 alpha cDNA has been isolated and this species homologous probe along with a rat S100 beta cDNA probe has been used to examine S100 mRNA expression in rat tissues. Although the rat S100 alpha cDNA was missing approximately 30 nucleotides of coding sequence, only 4 conservative changes in amino acid sequence were observed when the deduced amino acid sequence was compared to the bovine S100 alpha amino acid sequence. Thus, S100 alpha proteins, like S100 beta proteins, are highly conserved among species. All nineteen of the tissues examined (including cerebrum and cerebellum) contained S100 alpha mRNA. In addition, S100 beta mRNA was detected in thirteen of the nineteen tissues examined. These results are in agreement with previous protein distribution studies and further demonstrate that S100 proteins are not brain-specific and are expressed in a large number of tissues. Although S100 alpha and S100 beta mRNAs were detected in rat tissues which had previously been reported to contain S100 alpha and S100 beta protein, a direct correlation between the protein and mRNA levels were not observed, suggesting that different mechanisms regulate S100 expression in various tissues. S100 alpha exhibited a single similar size mRNA species (0.5 Kb) in all tissues examined, as did S100 beta (1.5 Kb), suggesting that the individual S100 proteins are expressed as single mRNA and protein products in rat tissues.     

Good titles makes good articles: designing of English titles for medical papers.]

Based on the experience of the author and an intensive study of the titles of English medical papers written by authors in English-speaking countries, the characteristics and styles of the titles were expounded with well-selected examples. The paper also introduces some practical skills to write good English titles and enumerates some frequently used structures and expressions, which might be helpful for potential Chinese contributors to medical journals.     

Inhibition of the expression of lysyl oxidase and its substrates in cadmium-resistant rat fetal lung fibroblasts.

Copper (Cu)-dependent lysyl oxidase (LO) catalyzes crosslinking of collagen and elastin stabilizing the extracellular matrix (ECM). Chronic inhalation of cadmium (Cd), a toxic metal, induces emphysema. To probe mechanisms of Cd injury to the lung, we developed Cd-resistant (CdR) cells from rat fetal lung fibroblasts (RFL6) by chronic exposure to CdCl(2) from 1 to 40 microM and further examined their expressions of LO, LO substrates, and Cu-scavenging thiols. Levels of cellular thiols, metallothionein, and glutathione in CdR cells were elevated to 13.0- and 3.2-fold of parental controls, respectively, whereas LO mRNA and protein levels were markedly reduced in these cells, with catalytic activity declining to only 16% of the parental control. A conspicuous 52 kDa species rather then the normal 50 kDa proenzyme appeared in the CdR cell extract but not in the conditioned medium, which was codistributed with the endoplasmic reticulum marker [DiOC5(3)] within the cell, implying the Cd-induced 52 kDa species as a product of an abnormal LO-processing defect in secretion. Addition of Cu into CdR cell cultures enhanced the expression of LO mRNA, protein and catalytic activities reflecting limitation of Cu bioavailability for LO in these cells. With inhibition of LO, CdR cells also displayed downregulation of collagen and elastin, substrates of LO. Restoration of collagen synthesis by exposure of CdR cells to purified LO or Cu suggests that inhibition of LO and limitation of Cu cofactor by Cd, as key phenotype changes, accelerated collagen and elastin damage, a critical event pertinent to emphysema pathogenesis.     

RNA干扰基因敲除MAGE-1在恶性胶质瘤U87细胞中的初步研究

目的：通过构建抑制MAGE-1的短片段双链核糖核酸（siRNA）表达载体，鉴定其在人恶性胶质瘤细胞系U87细胞中对MAGE．1基因表达的干涉作用。方法：化学合成2对编码短发夹RNA序列的靶向MAGE—1基因寡核苷酸链，克隆至经BglⅡ、HindⅢ双酶切的pSUPER载体上，重组构建核糖核酸干扰（RNAi）质粒载体。利用RT-PCR、流式细胞术和荧光显微镜，检测经稳定转染后胶质瘤U87细胞中MAGE-1的表达，以了解siRNA的干涉效果。结果：重组构建的pSUPER—MAGE—1载体经双酶切、电泳及插入基因片段序列分析，表明寡核苷酸链成功地插入至预计位点，且序列与预期完全一致。稳定转染后G418筛选出的U87多克隆细胞MAGE-1的表达经RT—PCR、流式细胞术和荧光显微镜检测，2对siRNA均有较明显的干扰作用。结论：载体的成功构建并能对U87细胞中的MAGE—1分子进行RNAi，为进一步研究MAGE—1在肿瘤中的作用，分析基因功能，展开肿瘤基因治疗奠定了基础。     

Laparoscopic Local Resection Based on Sentinel Node Evaluation for Early Gastric Cancer: A Preliminary Report

We previously reported that lymphatic mapping using isosulfan blue can be used to identify sentinel nodes (SNs). This study was undertaken to evaluate the feasibility of using the SN technique in treating early gastric cancer and to explore its usefulness for minimal invasive surgery. Twenty-three patients with early gastric cancer who underwent SN biopsy were retrospectively evaluated. Based on SN evaluation, individualized surgery was performed in five patients with T1N0M0 gastric cancer. When pathological examination of frozen sections revealed metastasis in SNs, we performed a standard D2 gastrectomy. Laparoscopic local resection was applied when the SN biopsy was negative. Our results showed that the success rate with SN biopsy in early gastric cancer was 100%, as were the accuracy, sensitivity, and specificity. All five patients with early gastric cancer had SNs negative for metastases both by frozen section and by postoperative pathology. Thus, all these patients underwent laparoscopic local resection without extended lymphadenectomy. We conclude that SN biopsy is a useful tool to individualize the operative procedure, and laparoscopic local resection can be safely performed using SN guidance in selected patients with early gastric cancer.     

膀胱肿瘤2350例临床病理学特点分析

目的 探讨膀胱肿瘤的发病现状、总体趋势和病理特点.方法 整理1980-2007年2350例膀胱肿瘤病理档案,分为1980-1989、1990-1999和2000-2007年3个时间段.应用SPSS 13.0软件分析3时间段患者性别、年龄及肿瘤组织学类型间的关系.结果 2350例膀胱肿瘤中男1854例,女496例.良性92例,恶性2258例,膀胱恶性肿瘤的发病人数逐年上升.发病高峰年龄从50～69岁推迟到60～79岁.1980-1989、1990-1999和2000-2007年3个时间段中男、女恶性肿瘤病例数分别为524例和113例(4.64:11 00)、589例和164例(3.59:1.00)、675例和193例(3.50:1.00),男性约为女性的3.80倍;3时间段男性发生膀胱尿路上皮癌年龄分别为(57.5±11.7)、(62.6±12.3)、(65.9±11.3)岁,女性分别为(58.7±13.6)、(60.7±12.1)、(65.8±12.0)岁,男女各年龄段分别比较差异有统计学意义(P<0.05).男性发生鳞状细胞癌、尿路上皮癌和腺癌年龄分别为(68.05±9.7)、(59.85±14.1)、(63.4±9.9)岁,差异有统计学意义(P相似文献   

维生素D受体基因多态性与汉族人群慢性牙周炎易感性的关系

目的 探讨维生素D受体(VDR)基因多态性与汉族人群慢性牙周炎(CP)易感性的关系。方法 收集汉族轻、中、重度CP患者共166例及80名无牙周炎对照者的颊黏膜拭子，以Chelex-100法提取DNA，采用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)方法测定VDR BsmI、VDR ApaI和VDR TaqI的基因型，分析组间基因型分布和等位基因频率的差异。结果 轻、中、重度CP患者中VDR ApaI等位基因A携带者明显多于对照组，重度CP与中度CP、重度CP与轻度CP患者间VDR ApaI基因型的分布差异均有统计学意义，中度CP与轻度CP患者间VDR ApaI基因型分布差异无统计学意义，而VDR BsmI、TaqI位点的基因型分布在患者组和对照组间差异无统计学意义。结论 VDR ApaI等位基因A可能与汉族人群CP的易感性有关。     

青蒿琥酯皮肤擦剂在小鼠和兔体内的药代动力学研究

将青蒿琥酯溶于苯二甲酸二甲酯,加适量氨酮制成皮肤擦剂。给兔脱毛后,皮肤涂抹此擦剂25mg/kg后,血药浓度达峰时间平均为2 h,峰浓度平均为1.80μg/ml。药物在兔体内平均驻留时间为3.54 h,清除半衰期约为2.46 h。给小鼠脱毛皮肤涂抹擦剂6.7,31.3和71.4 mg/kg,血药浓度在给药后0.5～4 h达高峰,峰浓度分别为0.82,2.05和7.11μg/ml,体内药物平均驻留时间为3.39,2.79及3.54 h,清除半衰期为2.35,1.93及2.45 h。可见,给兔及小鼠皮肤擦剂后,青蒿琥酯吸收良好,血药浓度维持时间较长。     

甲基苯丙胺抗体、疫苗以及检测试纸研究进展

苯丙胺类兴奋剂(amphetamine-type stimulants,ATS)是21世纪主要流行滥用的药物之一,目前社会上流行的"冰毒","摇头丸"等属于此类毒品,主要有甲基苯丙胺(methamphetamine,METH),亚甲基二氧基甲基苯丙胺(MDMA)等.在我国,此类毒品无论是在舞厅、迪吧或其它公共娱乐场所和地下色情场所等都很容易获得,导致滥用人群日益扩大[1],影响社会治安和社会稳定.虽然世界各国在药物滥用防治工作中投入了大量的人力、物力、财力,但收效甚微,对ATS依赖者目前治疗多采用强制戒毒、对症治疗和辅以心理治疗等方法,但治疗时间长,复吸率高[1-4],对于高危人群目前还没有一种有效的预防手段.检测ATS多用高效液相色谱(HPLC)、气相色谱-质谱联用(GC-MS)、薄层色谱(TLC)等[2]方法,其设备昂贵,难以开展现场检测,应用范围受限,并不适合于现场快速便捷检测,因而探索对ATS更有效的预防、治疗方法和更便捷的现场检测方法,极具现实意义.