Objective To evaluate the potential of specific mRNA marker keratin 19(K19) to detect micrometastasis by reverse transcriptase polymerase chain reaction (RT-PCR) .Methods One hundred and ninty four regional lymph nodes harvested from 6 cases of benign diseases, 4 cases of breast carcinoma, 5 cases of gastric carcinoma and 12 cases of colorectal carcinoma patients were examined by conventional pathology and amplifying tissue specific K19 mRNA by RT-PCR separately, then the two methods were compared with each other. Results None of the 34 lymph nodes which were pathological metastasis-negative from benign diseases expressed K19 mRNA by RT-PCR, all of the 28 regional lymph nodes which were pathological metastasis-positive from malignant cases showed trains of K19 mRNA by RT-PCR. Of the 132 lymph nodes which were pathological metastasis-negative from malignant cases, 11 lymph nodes were detected with micrometastasis by genetic diagnosis.Conclusion Genetic diagnosis of lymph node micrometastasis is more sensitive than conventional pathology and has diagnostic value and merits further study.
Objective To investigate the expression of T cell receptor (TCR) Vβ8.3 gene on CD4+ T lymphocytes in the rats with experimental autoimmune uveoretinitis (EAU). Methods Eighteen Lewis rats were divided into EAU, complete Freund′s adjuvant, and the control group. Inter photoreceptor retinoid-binding protein (IRBP) R16 peptide was synthesized using Fmoc procedure for induction of EAU. Magnetic absorption cell sorting (MACS) me thod was used to isolate the CD4+T lymphocytes from the spleen of the rats. Flow cytometry was used to monitor the efficiency of isolation. The expression of TCR Vβ8.3 gene segment on CD4+T lymphocytes was determined by fluorescent quantitative polymerase chain reaction. Results EAU was successfully induced in the Lewis rats immunized with IRBP R16 peptide. The proportion of CD4+T lymphocytes isolated by means of MACS was statistically higher than that before isolation (P＜0.001). The expression of TCR Vβ8.3 gene segment on CD4+ T lymphocytes in EAU rats was significantly higher than that in the control (P＜0.05). Conclusions There is a predominant usage of antigen-specific TCR Vβ 8.3 gene in EAU rats induced by IR BP R16 peptide, which may serve as a target for immunotherapy of EAU. (Chin J Ocul Fundus Dis，2004，20：165-167)
Objective To identify and isolate the variant gene associated with gastric adenocarcinoma and clone the fragment of variant gene.Methods By arbitrarily primer polymerase chain reaction (AP-PCR), DNA samples from 5 matched gastric adenocarcinoma and non-tumor gastric tissues were analysed. Results The produced AP-PCR profiles were different in each matched gastric adenocarcinoma and non-tumor gastric tissue. One differentiated amplified DNA fragments PW2.2 from a matched gastric adenocarcinoma were cloned. The result of Southern blot hybridization with PW2.2 as a probe showing that this fragment was also found in some other gastric adenocarcinoma samples. Conclusion AP-PCR fingerprinting assay can be used to identify and clone the variant genes associated with gastric adenocarcinoma.
Objective To investigate the effect of hypoxia on expressions of erythropoietin（EPO）mRNA and protein in retinal Muuml;ller cells cultured in vitro. Methods Retina tissues from the new-born Wistar rats were dissected into cell suspension after digested by pancreatin.Muuml;ller cells were separated and purified by mechanical concussion and blowing and striking method.The expression of EPO mRNA and protein under the condition of hypoxia was detected by semi-quantitative reverse transcriptase（RT）-polymerase chain reaction（PCR）and immunocytochemical method. Results Retinal Muuml;ller cells were cultured successfully，95% of which were positively stained by glial fibrillary acidic protein（GFAP）.Positively stained EPO protein was located in the cytoplasm and protuberance.The expression of EPO mRNA and protein was faint in the normal retinal Muuml;ller cells，but increased obviously and time-dependently after hypoxia. Conclusion Expression of EPO mRNA and protein increases in Muuml;ller cells after hypoxia，which may be one of the protective factors for the nerves in anoxic retinopathy. (Chin J Ocul Fundus Dis, 2006, 22: 196-199)
ObjectiveTo establish a method that can eliminate the pollution of endogenous nucleic acid in the real-time quantitative polymerase chain reaction (PCR) reaction system, which can be used to reduce or eliminate the false positive rate of real-time PCR assay in detection of postoperative intracranial bacteria infection.MethodsAt first, eliminated the pollution of endogenous nucleic acid in the real-time PCR reaction system. Then, with mixed bacteria DNA as a template, multiple PCR was used to specifically identify the gram-negative bacteria. Meanwhile, evaluated the text line and sensitivity of the multiple PCR after eliminating pollution in detecting the DNA of the mixed bacteria.ResultsThe method established could quickly eliminate the pollution of endogenous nucleic acid in the real-time PCR reaction system, and it didn’t affect the Taq enzyme activity and the amplification efficiency in PCR system, with the minimum detection limit of 102 CFU/mL (Staphylococcus aureus and Pseudomonas aeruginosa), which was the same to the culture method. The enzyme cutting method had no significant effect on the activity and amplification efficiency of the enzyme in PCR system, It had no effect on PCR reaction system and primer specificity (Ct=32, ΔRn=200). However, the filtration method significantly reduced the PCR amplification efficiency (Ct=32, ΔRn=150).ConclusionsThis method can easily and rapidly eliminate the pollution of endogenous nucleic acid in the real-time PCR reaction system, and greatly reduce the false positive of PCR detection. It is able to timely and accurately diagnose the intracranial bacteria infection, which is significant for clinical testing.
Objective To detect and analyse the mutations in rhodopsin gene of members in a family affected by autosomal dominant retinitis pigmentosa (ADRP). Methods Using the polymerase chain reaction (PCR), we amplified exon 1-5 of rhodopsin gene in patients with ADRP,and analyzed it with direct sequence measuement. Results The Gly-182-Asp mutation in the rhodopsin gene was detected in most of affected members of this ADRP family, but no mutation was detected in two affected members and the control ones. Conclusion We cannot regard the Gly-182-Asp mutation in the rhodopsin gene as the pathagenic factor of the ADRP family. It is likely there is a new gene next to the rhodopsin gene. (Chin J Ocul Fundus Dis, 2002, 18: 256-258)
Objective To investigate the transfection and expression of recombinant plasmid human vascular endothelial growth factor 165/pcDNA3. 1 （hVEGF165/pcDNA3. 1） in myocardial cells, and to build foundation for gene therapy and cell therapy of coronary artery disease （CAD）. Methods Myocardial cells were cultured in vitro and transfected by hVEGF165/pcDNA3.1 with liposome; then transient expressed protein was detected by reverse transcriptase-polymerase chain reaction （RT-PCR）, immunochemistry and Western blotting. Results A strap as hVEGF165 was obtained by RT-PCR, the protein of hVEGF165 was found in myocardial cells by immunochemistry and in supernatant by Western blotting. Conclusion The recombinant plasmid hVEGFI65/pcDNA3. 1 can be expressed in myocardial cells, and may be used in studying CAD by gene therapy and cell transplantation.
目的 比较评价磁珠法、柱子吸附法和煮沸裂解法3种不同的核酸提取方法对淋病奈瑟菌（淋球菌）DNA提取效率的差异。 方法 对已确诊的淋球菌培养基挑取20个小菌落制成悬液，做1︰1～1︰100 000稀释度稀释，分别使用磁珠法、柱子吸附法和煮沸裂解法进行DNA提取，用实时荧光定量PCR对其提取效率进行评价。 结果 在不同浓度淋球菌的DNA提取中，以磁珠法的敏感性和重复性最高，而柱子吸附法和煮沸裂解法次之，＜1×105 copies /mL以下的拷贝数，3种DNA提取方法之间重复性和敏感性差异明显，磁珠法的提取效率最高，柱子吸附法次之，煮沸裂解法最差；＞1×105 copies/mL的细菌拷贝数的样本，3种方法差异随浓度增高不断缩小。 结论 磁珠法提取淋球菌DNA的效率、敏感性和重复性最高，在实际临床科研工作中，各实验室可根据自身实际情况选择不同的DNA提取方法。
Objective To verify whetheriris pigment epithelial cells(IPECs)possess the similar potential of specific phagocytosis to retinal outer segments(ROS) with retinal pigment epithelialcells(RPECs). Methods IPESc were isolated from neonatal bovines with Hu's method,and were cultured.The cultured cells were identified by immunohistochemical methods with antibodies to cytokeratin and s-100.Total RNA of IPECs was extracted by Trizol.The specific primers for mannose-receptor andbeta;-actin were designed according to their sequence from Genbank.The mRNA expression of these proteins in the IPECs was analyzed by reverse transcription polymerase chain-reaction (RT-PCT).Results The Cultured IPECs have no contamination of other cells .The extracted RNA was ideal and had no degradation.RT-PCR analysis showed that mannose-receptor's mRNA was expressed in cultured IPECs in vitro.ConclusionCultured IPECs may express the mannose-receptor,and may have similar potential of phagocytosis to ROS with REPCs.