We have devised a highly sensitive, specific, and quantitative assay for multidrug resistance (mdr1) mRNA expression based on the reverse transcription-polymerase chain reaction (RT-PCR). mdr1 mRNA levels were detected in 30 human primary hepatocellular carcinoma (PHC) tissue and adjacent liver tissue. Five of the patients had received chemotherapy before hepatectomy. The results show that the level of expression of mdr1 gene is higher in tumor tissue than in adjacent liver tissue. mdr1 gene is overexpressed in PHC after chemotherapy. Furthermore, mdr1 gene expression in the treated tumor adjacent liver tissue is higher than that in untreated tumor adjacent liver tissue. Our results indicated that overexpression of mdr1 gene may be responsible for the intrinsic and acquired drug resistance of PHC.
Traditional bone repair materials, such as titanium, polyetheretherketone, and calcium phosphate, exhibit limitations, including poor biocompatibility and incongruent mechanical properties. In contrast, ceramic-polymer composite materials combine the robust mechanical strength of ceramics with the flexibility of polymers, resulting in enhanced biocompatibility and mechanical performance. In recent years, researchers worldwide have conducted extensive studies to develop innovative composite materials and manufacturing processes, with the aim of enhancing the bone repair capabilities of implants. This article provides a comprehensive overview of the advancements in ceramic-polymer composite materials, as well as in 3D printing and surface modification techniques for composite materials, with the objective of offering valuable insights to improve and facilitate the clinical application of ceramic-polymer composite materials in the future.
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 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.
Objective To study the influence of in vitro force-vascularization on in vivo vascularization of porous polylactic glycolic acid copolymer(PLGA) scaffolds with internal network channels (PPSINC). Methods After the in vitro forcevascula ization of PPSINCs covered with microvessel endothelial cells (MVEC) of mice, they were divided into two groups: the force-vascularization group (group A) and the control group with only PSINCs (group B). All the PPSINCs were planted in the mesentery of 12 mice for 2 and 4 weeks, the PPSINCs were cut out, the vascular ization of PPSINCs was investigated by histology and immunohistochemistry, and the vascularization area of the histologic section of the PPSINCswas measured with the computer-assistant image analysis system. Result After the in vitro forcevascularization of PPSINCs, the MVEC of the mice sticking on the channel wall could be seen. After the scaffold was im planted into the mice for 2 weeks, the vascularization area of the histologic section of PPSINCs (VA) in group A (2 260.91±242.35 μm2) was compared with that in group B (823.64±81.29 μm2),and the difference was sig nificant in statistics(P<0.01).The VA for 4 weeks in group A (17 284.36 ±72.67 μm2) was compared with that in group B (17 041.14±81.51 μm2), and the difference was not significant in statistics(P>0.05).The area of the actin positivestaining (AA) in the histologi c section of PPSINCs for 2 weeks’ implantation in group A (565.22±60.58 μm2) was compared with that in group B (205.91±16.25 μm2), and the difference was signi ficant in statistics(P<0.01). After the implantation for 4 weeks, the VA in group A (4 321.09±19.82 μm2) was compared with group B (4 260.28±27.17 μm2), and the difference was not significant in statistics(P>0.05). Conclusion The PPSINC is a good simple scaffold model of vasculariazation. The in vitro force-vascularization can increase the in vivo vascularization of PPSINCs in the early stage.
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)
【 Abstract 】 Objective To study the mRNA expression of BC047440 gene in multiplicate malignant tumor tissues and the corresponding adjacent tissues, and to investigate its roles in the carcinogenesis and development of malignant tumors. Methods Forty-eight cases of malignant tumor tissues and their adjacent non-cancerous tissues were examined. The mRNA expression of BC047440 gene in those tissues of liver cancer, cholangiocarcinoma, gastric cancer, carcinoma of large intestine, glioma, and breast cancer were measured by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). Results ① The mRNA expressions of BC047440 gene in liver cancer, gastric cancer, cholangiocarcinoma and carcinoma of large intestine were significantly higher than those in their adjacent non-cancerous tissues (Plt;0.05 or 0.01). BC047440 gene were highly expressed in both glioma and its adjacent tissues (Pgt;0.05), and poorly expressed in both breast cancer and its adjacent tissues (Pgt;0.05). ② There were close relationships between BC047440 gene expression and clinicopathologic findings of liver cancer, including tumor size and portal vein invasion (Plt;0.05). ③ There were also close relationships between BC047440 gene expression and different clinical stages in alimentary canal cancers (Plt;0.05). Conclusion The over expression of BC047440 gene may be related with the growth, infiltration and metastasis of some malignant tumors, including liver cancer, cholangiocarcinoma, gastric cancer, carcinoma of large intestine and glioma.
The mortality rate of ovarian cancer is the highest among female reproductive tract malignancies. Although most patients have undergone recurrent treatments such as surgery, chemotherapy, and targeted therapy, the recurrence rate is still high. The exploration of scholars in this field has never stopped. In recent years, remarkable achievements have been made in the medical treatment of ovarian cancer. The research of poly adenosinediphosphate-ribose polymerase, immunotherapy (immunocheckpoint inhibitor monotherapy, immune checkpoint inhibitor combined with other drugs) and anti-angiogenic drugs have provided new methods for the treatment of this disease, and throughout the whole process of ovarian cancer treatment. This paper summarizes this, and aims to provide a reference for the clinical treatment of ovarian cancer.
A multiple-stimuli-responsive drug-conjugated cross-linked micelles was prepared by radical copolymerization. The chemical structure, morphology, and size of the cross-linked micelles were characterized, and the drug loading of the micelle was calculated. The experimental results indicated that the hydrodynamic size of the drug-loaded micelles were about 100 nm, and the as prepared micelles could be degraded and swelled in presence of reducing glutathione (GSH). The low critical solution temperature (LCST) of the micelle was around 39.4℃. According to the experimental results, the micelles will shrink at temperature above the LCST. Subsequently, the accumulative drug release rate was up to 91.78% under acidic (pH 5.0), reductive (GSH 10 mmol/L) and high temperature (42.0℃) conditions mimicking the tumor microenvironment, while a relatively low release rate of 1.12% was observed without stimulation. The drug-conjugated cross-linked micelles showed a strong cell uptake behavior. In the cytotoxicity assay, the micelles exhibited effective anti-cancer activity and excellent biocompatibility. In brief, the experimental results show that the as-prepared drug-conjugated cross-linked micelle exhibits multiple stimuli-responsiveness, which holds great promise for anti-cancer drug delivery.
【Abstract】ObjectiveTo discuss the possibility and clinical significance of SSX-1 mRNA used as specific marker for examining HCC cells in peripheral blood of HCC patients. MethodsUsing the RT-PCR method, the SSX1 mRNA of the peripheral blood was examined in 25 cases of HCC patients and 20 non-HCC patients. The same method was used to detect the expression of SSX-1 mRNA in the tumor tissues, para-tumor tissues, cirrhosis tissues and normal hepatic tissues. A randomized sample was extracted for DNA sequencing from positive electrophoresis expression samples of SSX-1 to examine the reliability of results. ResultsThe expression rates of SSX-1 mRNA were 60%(15/25) and 40%(10/25) respectively in tumor tissues of HCC and the corresponding peripheral blood. SSX-1 mRNA were not expressed in para-tumor tissues,cirrhosis tissues and normal hepatic tissues. The DNA sequence -confirmed that the RTPCR products were true target cDNA. No relationships were found between the expression of SSX-1 gene and clinical characteristics, such as age, sex, tumor size, TNM stage, extent of differentiation and serum AFP level (Pgt;0.05). However, in 33%(3/9) patients with normal serum AFP (lt;20 μg/L), specific expression of SSX1 mRNA was observed. ConclusionHigh specific expression of SSX-1 mRNA is observed in the peripheral blood of patients with HCC, it suggests that applying it as a tumor marker to detect HCC cells in peripheral blood is an adjuvant diagnostic tool. The expression of SSX-1 mRNA in the peripheral blood is observed in the group HCC patients whose serum AFP (lt;20 μg/L) are normal, which suggests that applying both SSX-1 mRNA and AFP as tumor markers together might be useful to improve the diagnostic accuracy for HCC.