Objective To detect the expression level of miRNA-575 by pancreatic cancer stem cells.Methods Pancreatic cancer cell lines were cultured with serum-free medium.The cancer stem cells were obtained and their characteristics were observed with an invasion assay,a xenograft experiment,and flow cytometry analysis.Moreover,qRT-PCR was used to detect the expression of miR-575.Results A small subpopulation of cells in both ASPC-1 and PANC-1 cells survived and formed spheres in the absence of serum.The mean number of migrated cells of PANC-1 and ASPC-1 spheres was (147.3±18.6) cells and (113.2±12.9) cells.Therefore,the spheres have higher invasive ability compared with those of parental cells.As few as 5 × 105 cells in PANC-1 and ASPC-1 spheres could initiate a xenograft tumor in NOD/SCID mice,which suggested the tumorigenicity of the spheres was 100 times those of parental cell lines.The percentages of CD24+CD44+ in spheres were 0.38％-0.43％ and 4.91％-5.21％,which showed increased expression compared with ASPC-1 and PANC-1 cell lines (P＜0.05).The expression of miR-575 in spheres was 3.71 and 3.83 times its expression in cell lines ASPC-1 and PANC-1 respectively (P＜0.05).Conclusions Pancreatic cancer cell spheres may be a source for collecting cancer stem cells in a serum-free medium culture,and MiR 575 may play an important role in regulating the biological characteristics of pancreatic cancer stem cells.

Objective To investigate the changes of pulmonary capillary wedge pressure(PCWP) before and after off-pump coronary artery bypass graft(OPCABG) using transesophageal echocardiography(TEE). Methods Mitral valve flow(MVF) and pulmonary veinous flow(PVF) were measured in 46 patients before and after OPCAB using TEE and PCWP was detected by cardiac catheter. The correlations between indices derived from TEE and catheterization-measured PCWP and the differences before and after OPCAB were studied. Results There were obvious differences in the indices derived from TEE and PCWP which could reflect the left ventricular function. The most indices measured in PVF and MVF correlated with PCWP(r=(0.30)-(0.76),P

OBJECTIVE To study the gene chip joint pyrosequencing technology in the newborn genetic deafness gene mutation screening, and provide a theoretical basis for the early diagnosis and prevention of genetic deafness. METHODS 2000 Neonatal EDTA umbilical cord blood was collected and genomic DNA (gDNA) was extracted. Microarray chip was used to detect four deafness gene at 9 mutation sites. And the positive result of gene chip detection was verified by pyrosequencing.RESULTS Among the GJB2 mutations, there were 1 case of 35delG mutation type, 3 cases of 176 del16 mutation type, 57 cases of 235del C mutation type, 9 cases of 299 del AT mutation type, 6 cases of GJB3 gene 538C>T mutation type. There were 5 cases of 1555A>G mutations and 1 case of 1494C>T mutations in mitochondrial 12S rRNA. There were 6 cases of 2168A>G mutation type and 23 cases of IVS7-2A>G mutations in SLC26A4. 103 cases of newborns carry the mutated gene in 2,000, the gene mutation rate is 5.15%. CONCLUSION All the four genes mutation at nine mutation sites are found in newborns with family history of non-hereditary deafness, and GJB2 gene mutation is common. The screening of genetic deafness in newborns is very important for early diagnosis and prevention of hereditary hearing loss. In particular, the diagnosis of mitochondrial 12S rRNA gene mutation can prevent the occurrence of deafness caused by drug use, for the genetic mutation of these carriers' health is of great significance.

BACKGROUNDTo study the biological effects of multi-electrode radiofrequency ablation on pulmonary tissues of rabbits.

METHODSUnder the guidance of computer tomograph, electrodes were inserted into right lungs of New Zealand white rabbits and radiofrequency was performed. The biological effects were observed through CT image and microscopy.

RESULTSCoagulative necrosis was found immediately in ablation area after the procedure. On the 7th postradiofrequency ablation day, fibrous tissues appeared in the necrotic lesions. On the 30th postradiofrequency ablation day, bronchial and alveolar epithelium began to proliferate. Within 60 to 90 days after treatments, the necrotic lesions were almost replaced by normal pulmonary tissues. In group with electrodes into the right hilum, time for treating and initial impedance were significantly different from those with electrodes into the peripheral sites of the right-lower lobes (P < 0.01, P < 0.01).

CONCLUSIONSMulti-electrode radiofrequency ablation can be safely and effectivly performed in pulmonary tissue and cause coagulative necrosis within a certain extent.

BACKGROUNDTo observe the CT appearance and pathological changes of VX2 tumor in rabbit lung after radio-frequency ablation.

METHODSAfter VX2 tumor tissue suspension was injected into the lungs, the transplanted lung cancer models were established in 36 New Zealand white rabbits. Twenty-eight rabbits were treated with radio-frequency ablation, and another 8 rabbits without any treatment as control. The CT appearances and pathological changes were observed in different time intervals after the treatment in 14 rabbits out of experimental group. The survival periods of the rabbits were recorded in the rest 14 rabbits of experimental group and the control group respectively.

RESULTSCoagulative necrosis and cell apoptosis appeared in the tumor tissues after the ablation, and inflammatory cells were found in the lung tissues around the areas of ablation. Wadding shadows appeared in CT images after the treatment and disappeared with the inflammation vanished, but the tumor shadows ceased to increase. In the experimental group, tumor tissues were almost necrosed in the target areas of 21 rabbits, however, peripheral residual nests of histologically viable tumor were found in the target areas of the other 7 rabbits. The survival periods of rabbits in the experimental group and the control group were 38 days±3.4 days days and 26 days±2.8 days respectively (P < 0.05).

CONCLUSIONSRadio-frequency ablation may be an effective method in the treatment of lung cancer.

Objective To investigate the transcriptome differences of ovarian cancer cells after cisplatin(DDP)resistance,and to find potential antagonists based on this screening.Methods DDP-resistant cell line A2780-DDP was constructed with A2780 cells as the research object.Through transcriptome sequencing anal-ysis,the key factors of DDP resistance were found and verified by quantitative real-time PCR(qPCR)and Western blot experiments.Through the screening of small molecule inhibitors,CCK-8 cell viability assay was used to find potential antagonists.Results A2780-DDP were successfully constructed,and it was found that there was no difference in cell proliferation after drug resistance,but the ability of cell invasion and migration was enhanced.Through transcriptome sequencing analysis,it was found that ITGB7 and Akt may be the key genes of A2780-DDP,and qPCR and Western blot showed that they were highly expressed in A2780-DDP.CCK-8 results showed that triptolide(TPL)and Olaparib had good inhibitory effects in DDP-resistant cell lines.Conclusion The ITGB7/Akt pathway plays an important role in DDP resistance,and potential DDP re-sistance antagonists such as TPL can provide new ideas for the treatment of ovarian cancer.