Advances of liquid biopsy in the diagnosis and treatment of tumor / 国际肿瘤学杂志

Liquid biopsy mainly focuses on tumor diagnosis,metastasis monitoring,individualized treatment monitoring,curative effect evaluation and prognostic judgment.The main targets include circulating tumor cells,circulating tumor DNA and exosomes.At present,the liquid biopsy target has been used in the clinical monitoring of some tumors,and has good clinical results,but there are still many cha-llenges.

Nucleic acid dye GeneGreen can influence the quality of DNA bands in agarose gel electrophoresis / 国际检验医学杂志

Objective To explore the causes of twisted or tailed DNA bands in agarose gels after electro-phoresis .Methods Prestained and poststained methods were employed to exam 3 kinds of DNA marker bands in agarose gel with GeneGreen and Ethidium Bromide ,respectively .Results Three kinds of DNA marker bands in agarose gel with 1:10000 and 1:5000 concentration of GeneGreen showed obvious distortions and trailing phenomena compared with the same concentration of Ethidium Bromide w hen the prestained method was used for electrophoresis ,which were improved when the poststained method was used in agarose gel with GeneGreen and Ethidium Bromide ,respectively .Conclusion Nucleic acid dye GeneGreen can affect the quali-ty of DNA bands in agarose gel electrophoresis .When the quality of DNA itself ,agarose gel quality ,electro-phoretic fluid quality and voltage are excluded ,the quality of nucleic acid dye should be taken into considera-tion if the bands twisting or tailing occurs when the DNA nucleic acid electrophoresis is carried out by pres-tained method .The quality of DNA electrophoresis bands can be improved by using poststained method or re-placing nucleic acid dye .

Promoting Vasa Vasorum Neovascularization of Vein Grafts Extenuates Hypoxia of the Wall and Its Subsequent Influence on Intimal Hyperplasia / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The autologous saphenous vein is the most common conduit for coronary artery bypass grafting, but the vein graft disease will occur. This study used Matrigel basement membrane matrix with many different growth factors to promote vasa vasorum neovascularization and extenuate the hypoxia to improve remodeling.</p><p><b>METHODS</b>This study observed the hypoxia and thickness of the vein grafts at different times. Normal veins and vein grafts with 15 min of ischemia one day postoperatively were harvested in the neck of rabbits. Paired vein grafts with 15 min ischemia bilaterally (control vs. Matrigel basement membrane matrix) were performed and harvested at 2, 6, and 12 weeks postoperatively. The rabbits were randomly divided into four postoperative groups (six rabbits in each group): Group 1, one day postoperatively; Group 2, 2 weeks postoperatively; Group 3, 6 weeks postoperatively; and Group 4, 12 weeks postoperatively. The dimensions of vessel wall were captured, and the mean thicknesses of intima, media, and adventitia were measured. The hypoxia-inducible factor (HIF)-1α and HIF-2α labeling indices of intima, media, and adventitia were also measured.</p><p><b>RESULTS</b>In Group 1, the labeling index of HIF-1α was high in the normal vein and decreased significantly in the vein graft one day postoperatively (intima: 80 ± 3% vs. 12 ± 1%, P = 0.01; media: 67 ± 5% vs. 11 ± 1%, P = 0.01; adventitia: 40 ± 10% vs. 7 ± 2%, P = 0.03). The labeling index of HIF-2α had similar trend as HIF-1α (intima: 80 ± 10% vs. 10 ± 5%, P = 0.02; media: 60 ± 14% vs. 12 ± 2%, P = 0.01; adventitia: 45 ± 20% vs. 10 ± 4%, P = 0.03). Compared with the control vein grafts, vein grafts with Matrigel basement membrane matrix had lower labeling indices of HIF-1α and HIF-2α in media and adventitia at Group 2 (HIF-1α: 34 ± 5% vs. 20 ± 4%, P = 0.04 for media; 23 ± 3% vs. 11 ± 2%, P = 0.03 for adventitia; HIF-2α: 37 ± 6% vs. 21 ± 4%, P = 0.03 for media; 24 ± 4% vs. 13 ± 2%, P = 0.04 for adventitia) and Group 3 (HIF-1α: 33 ± 4% vs. 7 ± 2%, P = 0.04 for media; 13 ± 3% vs. 3 ± 1%, P = 0.02 for adventitia; HIF-2α: 27 ± 4% vs. 12 ± 3%, P = 0.02 for media; 19 ± 2% vs. 6 ± 1%, P = 0.02 for adventitia). There were no differences in mean thickness of intima, media, and adventitia between bilateral vein grafts at 2, 6, and 12 weeks postoperatively.</p><p><b>CONCLUSIONS</b>This study indicated that promoting vasa vasorum neovascularization of vein grafts extenuated hypoxia, but did not influence the intimal hyperplasia of the wall.</p>

Correlation between polymorphism in the promoter of DNA methyltransferase-3B gene and susceptibility of colorectal cancer / 国际生物医学工程杂志

Objective To observe and analyze the correlation between the DNA methyltransferase-3B (DNMT3B) gene single nucleotide polymorphisms (SNP) rs 1569686 and the susceptibility to colorectal cancer (CRC) in Tianjin Han population.Methods A case-control study was performed.89 CRC patients and 94 normal controls were examined,and Sequenom MassArray system was applied to detect the genotype of rs1569686 in DNMT3B gene polymorphisms.The association results were analyzed of the SNP and CRC.Results The frequencies of genotypes TT,GT and GG at SNP rs1569686 were 74.2％,24.7％ and 1.1％ in CRC patients respectively,which there were no significant differences from that in controls(73.4％,23.4％ and 3.2％; P＞0.05).Conclusion It suggests that the SNP rs1569686 of DNMT3B gene may not be related to susceptibility of CRC in Tianjin Han population.

Medical risk management for resident doctors in their standardized training / 中华医院管理杂志

An analysis of the medical risks exposure for resident doctors in their standardized training,and insights into the risk management measures proposed for this stage.These measures include:1) Pre-control of risks;2) Full-length supervisor of such training stage;3) Systematic education for medical risk exposure;4) Timely guidance on risk identification and response;5) Development of the evidence awareness.

Effect of external stents on prevention of intimal hyperplasia in a canine vein graft model / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>External stents have been used to reduce intimal hyperplasia of vein grafts. The aim of the present study was to define the size of an external stent appropriate for a particular graft by comparing vein grafts with different sizes of external stents.</p><p><b>METHODS</b>A series of paired trials was performed to compare femoral vein grafts with different sizes of external stents, where 30 modeled canines were equally divided into three groups: 6-mm external stent vs non-stent control, 4-mm vs 6-mm external stent, and 4-mm vs 8-mm external stent. At day 3 after operation, color Doppler flow imaging (CDFI) was done to observe blood flow in the lumen. Four weeks later, CDFI was re-checked and the veins were harvested, stained and measured.</p><p><b>RESULTS</b>All grafts were patent without formation of thrombosis. External stents significantly reduced intimal thickness of the vein grafts with a 6-mm external stent compared with the vein grafts without external stents (P < 0.05). The vein grafts with the 4-mm external stent had similar intimal, medial and adventitial thicknesses compared with those with the 6-mm external stent and the 8-mm external stent.</p><p><b>CONCLUSIONS</b>External stents can reduce intimal hyperplasia of vein grafts. Stents of different diameters exert the similar effect on prevention of intimal hyperplasia.</p>

Oxidative stress-induced accumulation of heat shock protein 70 within nucleolus / 中南大学学报(医学版)

OBJECTIVE@#To investigate the effect of oxidative stress on the accumulation of heat shock protein 70 (HSP70) within C2C12 myogenic cells.@*METHODS@#Heat shock response (42 degrees C for 1 h and recovery for 12 h at 37 degrees C) was used to induce the expression of heat shock protein 70. We constructed a recombinant plasmid of HSP70 with enhanced green fluorescent protein (EGFP). After being transfected transiently into C2C12 cells, immunoblotting was used to detect the expression of HSP70 induced by heat shock response and transfection. Immunocytochemistry, fluorescent microscopy and immunoblotting were used to detect the translocation of HSP70.@*RESULTS@#Immunoblotting showed that the overexpression of HSP70 was induced by heat shock response and transient transfenction. HSP70 localized within the cytoplasm of the normal cells, but HSP70 translocated from the cytoplasm to the nucleus and the nucleolus at 1 h after the treatment of oxidative stress (0.5 mmol/L H2O2) by using immunocytochemistry, fluorescent microscopy and immunoblotting for cellular partial proteins.@*CONCLUSION@#Oxidative stress may induce the accumulation of heat shock protein 70 within the nucleolus.