【Abstract】Objective To explore the relation between the expression of telomerase and DNA ploidy with biliarypancreatic system cancer, so as to find a better way to diagnose and distinguish jaundice between malignance and benign disease.Methods Endoscopic retrograde cholangiopancreatography (ERCP) were performed before operation in patients with obstructive jaundice. The bile and pancreatice juice were collected before ERCP. Biopsy specimens from part of patients were obtained during ERCP. All cancer specimens were possessed once again during operation and were assessed by the activity of telomerase and DNA ploidy. Results ① Telomerase positive rate 〔87.50%(56/64)〕 of tissue specimens in malignant obstructive jaundice were higher than that in benign obstructive jaundice 〔3.33%(2/60)〕，P=0.000. ② Telomerase positive rate〔71.88%(46/64)〕of Bile and pancreatice juice in malignant obstructive jaundice were higher than that in benign obstructive jaundice 〔3.33%(2/60)〕， P=0.000, tissue specimens obtained by endoscopy with malignant obstructive jaundice had detectable telomerase activity, positive rate was 83.33%（20/24）. ③ The rate of DNA heteroploid with malignant obstructive jaundice was 62.50%（40/64）, that of diploid can be seen in all patients with benign obstructive jaundice, the difference was statistically significant (P=0.000). ④ The rate of telomerase positive and DNA heteroploid in high differentiation tumor were significantly lower than in middlelow differentiation tumor （P=0.028，P=0.001）.Conclusion Applying the duodenoscope we collected the bile and pancreatic fluid before operation and obtain biopsy specimens whose telomerase activity and DNA ploid were detected. This is simple, safe, quick method which can identify the malignant and benign obstructive jaundice.
ObjectiveTo analyze the variation of perioperative concentration of mitochondrial DNA (mtDNA) in circulation system after cardiac surgery with cardiopulmonary bypass (CPB).
MethodsBetween July and December 2014, 40 continuous patients underwent aortic valve replacement (AVR) and mitral valve replacement (MVR) in Department of Cardiovascular Surgery, West China Hospital, Sichuan University, including 16 males and 14 females with their mean age of 48.7±11.0 years and mean body weight of 59.0±6.9 kg. Perioperative mtDNA concentrations of circulatory blood were tested at different time points:before general anesthesia (T1), 1 min before CPB (T2), reperfusion of the ascending aorta (T3), 6 h after operation (T4), 24 h after operation (T5), 48 h after operation (T6).
ResultsAll the surgeries were successfully performed without early death. Postoperative complications were low cardiac output syndrome in 3 cases and acute kidney failure in 1 cases. The concentration of mtDNA in circulation system rising gradually after CPB. The mtDNA concentration of T3, T4 and T5 were significantly higher than T1 (P < 0.05). The peak level was observed at T5 and the mtDNA concentration of T6 was still significantly higher than that of T1 (P < 0.05).
ConclusionThe concentration of mtDNA in circulation system was rising after CPB and peak level appeared at 24 h after CPB.
How to improve the performance of circulating tumor DNA (ctDNA) signal acquisition and the accuracy to authenticate ultra low-frequency mutation are major challenges of minimal residual disease (MRD) detection in solid tumors. In this study, we developed a new MRD bioinformatics algorithm, namely multi-variant joint confidence analysis (MinerVa), and tested this algorithm both in contrived ctDNA standards and plasma DNA samples of patients with early non-small cell lung cancer (NSCLC). Our results showed that the specificity of multi-variant tracking of MinerVa algorithm ranged from 99.62% to 99.70%, and when tracking 30 variants, variant signals could be detected as low as 6.3 × 10?5 variant abundance. Furthermore, in a cohort of 27 NSCLC patients, the specificity of ctDNA-MRD for recurrence monitoring was 100%, and the sensitivity was 78.6%. These findings indicate that the MinerVa algorithm can efficiently capture ctDNA signals in blood samples and exhibit high accuracy in MRD detection.
Microorganism distributes in the organs of human body which connect with external environment, especially those organs in the gastrointestinal tracts, and it also plays a fundamental role in the physiopathology of the host's body. Because the microorganism is very small and has a great variety, it is difficult to reveal the significance of microorganism in the human physiopathology comprehensively and deeply. With the development of molecular biology, genomics, bioinformatics and other disciplines, the microbiome research will be more possible and easier. There are two key contents of microecology. One of these is to identify and quantify the diversity of microorganism, and the other is to reveal activity and the physiopathological function of microorganism in the host. Microbiome research methods, therefore, can be summarized as the traditional detection methods, construction of gene library, the genetic fingerprint analysis and molecular hybridization techniques and so on.
ObjectiveRecent advancements in the researches on cholangiocarcinoma (CC) related genes methylation in CC were reviewed and the clinical significances of aberrant DNA methylation for the diagnosis and treatment of CC were discussed. MethodsRelevant literatures about the relation between CC-related genes methylation and CC published recently were collected and reviewed. ResultsThe genesis of CC resulted from abnormal expressions of many genes. Many researches had shown that the abnormal methylation of CC-related genes had a close relation with CC. Epigenetic alteration had been acknowledged as an important mechanism contributing to early CC carcinogenesis. ConclusionsAbnormal methylation of CC-related genes is related with CC. The detection of CC-related genes methylation might provide new specific biomarkers for early noninvasive diagnosis of this disease. Using epigenetic agents such as azacytidine to modulate the activities of DNA methyltransferase and reverse the methylation status of CC-related gene might be an attractive strategy for future treatment of CC, which could be combined with conventional therapies.
ObjectiveTo explore the presence of common genetic alterations in retinoblastoma and to localize the altered genomic regions.MethodsGenetic instability of chromosome 19, 20, 21, 22 and X of 15 microdissected retinoblastoma tumors were analyzed by the loss of heterozygosity (LOH) and microsatellite instability (MSI).ResultsAmong the 15 patients with retinoblastoma, genome instability ［LOH and(or) MSI］ at one or more loci on the 5 chromosomes in 10 (67%), in which the loss of a single allele was more frequent in chromosomes 19 (33%) and 20 (27%) than in the other 3 chromosomes. Highfrequency LOH between D19S902 and D19S571 suggested gene loci in the 19q13 region might be associated with tumor development in retina. According to the result of MSI, MSI occured at least in one subset of retinoblastoma.ConclusionsOur results provide first evidence of LOH in chromosomes 19 and 20 in retinoblastoma and further support the presence of genome instability in retinoblastoma that may play an important role in the tumorigenesis or progression of retinoblastoma.(Chin J Ocul Fundus Dis, 2005,21:28-31)
Objective To investigate the genetic polymorphism of methicillin resistant Staphylococcus aureus ( MRSA) isolated from hospital acquired pneumonia. Methods Seventy-four hospitalized patients were diagnosed as noscomial MRSA pneumonia from January 2007 to January 2008 in Xinhua Hospital, Shanghai Jiaotong Univesity. The genes of MRSA were amplified by random amplified polymorphic DNA typing ( RAPD) assay in 82 clinical isolates from these patients. Results Two to 15 amplified DNA fragments were observed in agarose gel and they were classified into 11 genotypes. Genotypes Ⅲ, Ⅵ and Ⅶ ( 32. 56% , 30. 23% and 13. 95% , respectively) were mainly isolated from the ICU. Both independent genotypes and overlapping genotpyes with those from ICU were identified in isolates from the departments of geriatrics, emergency and respiratory medicine. Outbreak or cluster cases ( 48. 65% ) were found in 36 of the 74 patients while all outbreak cases occurred in the ICU. Conclusions Noscomial MRSA pneumonia is easy to disseminate and small-scale outbreak may occur especially in ICU. RAPD is valuable for identification and prevention of the spread of MRSA in hospital.
ObjectiveTo investigate the difference of DNA methylation before and after bariatric surgery.MethodThe relevant literatures of the research on the changes of DNA methylation level and gene expression regulation in blood and tissues before and after bariatric surgery were retrieved and reviewed.ResultsDNA methylation was an important method of epigenetic regulation in organisms and its role in bariatric surgery had been paid more and more attention in recent years. Existing studies had found that there were changes of DNA methylation in blood and tissues before and after bariatric surgery. The degree of methylation varies with different follow-up time after bariatric surgery and the same gene had different degrees of methylation in different tissues, and some even had the opposite results.ConclusionsDNA methylation levels before and after bariatric surgery are different in different tissues. And studies with larger sample size and longer follow-up time are needed, to further reveal relationship among DNA methylation, obesity, and bariatric surgery.
Objective
To analyze the relationship between genotype and phenotype of vitelline macular dystrophia (VMD2) gene in a family with Best disease, and to provide the theoretical basis for gene diagnosis of Best disease.
Methods
Mutation in the coding regions and the promotor sequence of VMD2 gene from 10 members in a family with Best disease were screened by polymerase chain reaction (PCR) and direct DNA sequencing, and combined with a conformation sensitive gel electrophoresis (CSGE) approach, VMD2 gene screening was performed on 100 normal control individuals.
Results
In the 10 members, Trarr;C nucleotide change at the 223 base of exon 3 was detected in 9, including 6 with Best disease who was confirmed by ophthalmoscopy and electrophysiological examination in whom 2 were affirmed as having homozygote of this mutation. Other 3 young family members with VMD2 gene mutation only had abnormal electro-oculogram manifestations. Above mutation was not detected in the normal control individuals.
Conclusions
The phenotype and genotype of VMD2 in the family with Best disease is highly correlated. Mutation in VMD2 gene is the nosogenesis in this family. Mutation screening of VMD2 gene can be used for genic diagnosis and genetic consultation of Best disease.
(Chin J Ocul Fundus Dis, 2006, 22: 86-89)
