Cancer stem cells: Current status / 第二军医大学学报

Recently, study on cencer stem cells has been a focus of study. Cancer stem cell is a small population of cencer cells possessing the properties of stem cells: self-renewal, differentiation and proliferation. To date, the existence of cancer stem cells has been proven in acute and chronic myeloid leukemia, breast cancer, brain tumors, liver cancer and colon cancer, etc.. In this article we reviews the current progress on cancer stem cells, including the defination, existing evidence, research methods, and challenges in clinical application.

p75NTR in isolation and identification of cancer stem cells from human esophageal carcinoma / 第二军医大学学报

Objective: To isolate and identify cancer stem cells from esophageal cancer cells (ECCs) using cell surface marker p75NTR. Methods: ECCs were cultured from surgically resected ECC specimens; ECC cell lines TE-1 and Ecal09 were also cultured. The expression of p75NTR in human ECCs was examined by flow cytometry. p75NTR positive cells were isolated from ECCs using magnetic activated cell sorting (MACS) method. The proliferation, differentiation, and the ability of colony-forming in soft agar of the p75 NTR positive cells were observed. The p75NTR positive cells were injected into BALB/c nude mice subcutaneously to observe their tumorigenesis ability. The survival rates of p75NTR positive and negative cells were assessed after treated with chemotherapy drugs to evaluate the resistance of p75NTR positive cells. Results: Six out of the eight cell lines, including SHEC-4, SHEC-6, SHEC-7, SHEC-8, EcalO9, and TE-1, were positive of p75NTR, with the positive rates being 2.71%, 0.32%, 3.35%, 1.13%, 2.15%, and 0.45%. respectively. It was showed that p75 NTR positive cells possessed higher proliferation ability compared with p75NTR negative cells (P<0.01). The p75NTR positive cells had higher colony-forming ability in soft agar compared with p75NTR negative cells (P<0.01). The p75NTR positive cells demonstrated stronger tumorigenesis ability in nude mice. As few as 2 000 SHEC-7 cells could give rise to new tumors in xenotransplantation, with a tumorigenesis ability 50 times as high as that of the p75NTR negative cells. When treated with chemotherapy drugs for 48 h, p75NTR positive cells had significantly higher survival rate than p75NTR negative cells (P<0.05). Conclusion: The p75NTR positive ECCs possess self-renewal, differentiation, and proliferation abilities; they are strongly resistant to chemotherapy drugs, which gives them strong tumorigenesis ability and the characters of tumor stem cells.

Repair of occipital and nuchal wounds with inferior trapezius myocutaneous flaps in patients after high voltage electrical burn / 中华烧伤杂志

<p><b>OBJECTIVE</b>To explore the methods and effects of repair of occipital and nuchal wounds with inferior trapezius myocutaneous flap after deep electrical bum.</p><p><b>METHODS</b>Twelve patients with high-voltage electrical burn in occipital and nuchal regions were hospitalized to our ward from March 2003 to September 2007. They were repaired with improved inferior trapezius myocutaneous flaps after debridement. Flaps were of two types: (1) blood supply from cutaneous and perforator branches of the original segment of the superficial descending branch of transverse cervical artery. (2) combined blood supply from both superficial and deep descending branches of transverse cervical artery C, i.e., dorsal scapular artery). All flaps carried segmental and limited trapezius muscle cuff surrounding the vascular pedicle of the flap similar to a perforator flap.</p><p><b>RESULTS</b>Flaps survived completely primarily in eight cases. In two patients, infection developed in flaps adjacent to wounds with lignification; they healed after dress change. Necrosis appeared in distal end of flap (one case), it healed after re-operation. One patient with surviving flaps died of sepsis and multiple organ failure 21 days after operation. The flaps which survived were not swollen ; the donor sites at scapular region looked normal without pterygoid or pendulous scapula deformities.</p><p><b>CONCLUSION</b>Inferior trapezius myocutaneous flaps can be used to repair occipital and nuchal wounds, with the advantages of constant blood vessels, reliable blood supply, convenience for application.</p>

Expression of matrix metalloproteinase-2, -9 and their inhibitor-1 in hypertrophic scars / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the gene expression of matrix metalloproteinases (MMP-2, MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in proliferative and mature hypertrophic scars.</p><p><b>METHODS</b>Total RNA from 8 normal skin samples and from 16 human hypertrophic scar samples of different maturing stage was respectively extracted, and then mRNA was isolated. The gene expressions of MMP-2, MMP-9 and TIMP-1 in these samples were examined with reverse transcription-polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>The gray scale ratio of MMP-2, MMP-9 and TIMP-1 transcription in normal skin were (3.8 +/- 0.7)%, (5.8 +/-4.4)%, (30.3 +/- 3.0)%, respectively, which were obviously higher than those in proliferative hypertrophic scar [(14 +/- 5)%, (18 +/- 5)%, (38 +/- 4)%, P < 0.05]. The expression of MMP-2 and MMP-9 genes in mature hypotrophic scar returned to normal level, but that of TIMP-1 remained high when compared with that of normal level (P < 0. 05).</p><p><b>CONCLUSION</b>The increase in MMP-2, MMP-9 and TIMP-1 gene expression might be involved in the formation of hypertrophic scars, while the lowering of MMP-2 and MMP-9 gene expression might be associated with the maturation of hypertrophic scars.</p>

RHCE genotyping in Chinese Han from north and Li from south / 法医学杂志

OBJECTIVE@#To establish a method which processes RHCE genotyping with PCR.@*METHODS@#Using PCR-SSP to detect RHCE genotype in 200 cases of Han population in north of China and Li population in south of China and detecting 5 samples of parentage testing at the same time.@*RESULTS@#The results of RHCE genotyping in individuals of two populations are completely accorded with the results of serology typing. And the distribution of RH genotypic frequency in Han population in north China is: RHCCEE 1, RHCCEe 3, RHCCee 88, RHCcEE 4, RHCcEe 20, RHCcee 54, RHccEE 1, RHccEe 22, RHccee; The distribution of RH genotypic frequency in Li populatin in south China is RHCCEE 2, RHCCEe 2, RHCCee 106, RHCcEE 7, RHCcEe 62, RHCcee 10, RHccEE 3, RHccEe 8. The results of RHCE genotype detecting of parentage testing samples are accorded with the results of associated identification of 13 STR loci.@*CONCLUSION@#PCR-SSP technology can exactly detect RHCE genotype in individuals of Han population in north China and Li population in south China.

A PCR-RFLP analysis to HLA-B gene among Chinese northern Han populations / 法医学杂志

OBJECTIVE@#To set up the method for analyzing HLA-B gene polymorphism with PCR-RFLP, and to gain population data among northern Chinese Hans of HLA-B's restricted fragments after NlaIII digestion, and to achieve application in forensic medicine practice.@*METHODS@#Sample DNA was extracted by the phenol/chloroform extraction method, 943 bp-long fragments containing HLA-B exon 2 and 3 were got by PCR. The endonuclease NlaIII was applied to cut the PCR products into polymorphic fragments shorter than 943bp, then PAGE and silver staining were used to detect the digestion results, finally the digestion sites were assured by DNA sequencing.@*RESULTS@#Along 943bp-long PCR products, 14 length-different fragments, 20 kinds of fragment combinations were got and 6 cutting site were observed after NlaIII digestion.@*CONCLUSION@#HLA-B gene was highly polymorphic among Chinese northern Hans. Even with only one endonuclease, 14 restricted fragments were got and the PIC was great. Such a HLA-B PCR-RFLP analysis will have values in forensic medicine applications.

Molecular biology advance in the Rh blood group system / 法医学杂志

The Rh blood group system is one of the most complex of the known human blood group polymorphisms, including above 45 blood group antigens. Considerable progress has been made in our understanding of the molecular basis of Rh in the past 10 years. The bases of Rh inheritance, RH gene and its evolution, the structure and function of Rh complex, as well as nonerythroid Rh homolog, have been determined. Further improvements have been made in the technology of Rh genotyping. The review provides an update on the advance of Rh blood group to give information in the practice of forensic science.

The affect of the skin stretch on the biomechanical changes of skin / 中华整形外科杂志

<p><b>OBJECTIVE</b>To investigate the biomechanical changes in skin after employing the skin stretch.</p><p><b>METHODS</b>Skin samples were took from the test group which was stretched for 7 days and control group without stretch respectively in the end of 1, 2, 3, 4, 6, 8 week. The biomechanical index were measured by tensiometer.</p><p><b>RESULTS</b>The mean destroy stress, breaking load, stretch rate of the test group decreased obviously in the first week (the breaking load was increasing at the beginning) and the three index increased subsequently, they reached the climax during the fourth week and turned to normal subsequently to the level of some higher than control group and normal value in the sixth week. The stiffness of the test group reached the climax at the first week and than decreased gradually to the level of some higher than normal value and control group. The biomechanical changes of te control group was not evident by comparing with the test gropu.</p><p><b>CONCLUSIONS</b>Skin stretch may injured the biomechanical property during the early time and turned to normal soon afterwards. The stiffness of the skin was increased and its elasticity was decreased after performing skin stretch.</p>

A novel regulable sutureless aortic arch prosthesis:an experimental study / 第二军医大学学报

Objective:To develop a novel regulable sutureless aortic arch prosthesis and to apply it in an animal experimental study.Methods:The arch skeleton of the prosthesis was made of tandem Z-shape NiTiNOL wire;the branch skeleton was made of laser-cut NiTiNOL tube;and the whole skeleton was coated with thin ePTFE film.The blood vessel was anastomosed by di- rect ligature,needing no manual suturing.The prosthesis was applied in swine aortic arch operations under the bypass condi- tion.The practicality for surgery and the feasibility of anastomosis of the prosthesis were assessed.Results:Aortic arch opera- tions were successfully performed in 6 of the 8 experimental animals.The prostheses were easy to use,and the mean bypass time was only 10 min.The blood loss of the anastomoses was less than 100 ml within 8 h postoperatively in 5 animals;one had more blood loss due to prosthesis mismatch.Conclusion:The novel regulable sutureless aortic arch prosthesis has satisfactory practicality for surgery and reliable anastomosis,making it promising in future clinical application.

Cancer stem cells:current status / 第二军医大学学报

Recently,study on cencer stem cells has been a focus of study.Cancer stem cell is a small population of cencer cells possessing the properties of stem cells:self-renewal,differentiation and proliferation.To date,the existence of cancer stem cells has been proven in acute and chronic myeloid leukemia,breast cancer,brain tumors,liver cancer and colon cancer,etc..In this article we reviews the current progress on cancer stem cells,including the defination,existing evidence,research methods, and challenges in clinical application.