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find Keyword "突变" 197 results
  • Advances in Basic Research and Clinical Progress in Hereditary Pancreatitis

    Objective To study the basic and clinical achievements in diagnosis and therapy of hereditary pancreatitis. Methods Related literatures of recent years were reviewed. Results Hereditary pancreatitis was a rare type of pancreatitis, with an estimated penetrance of 80%, and was believed to be caused by a mutation in the cationic trypsinogen gene. Patients with hereditary pancreatitis had a high frequency of pancreatic cancer.Conclusion The progress has been made on hereditary pancreatitis and has given us many useful suggestions for a better understanding about this difficult medical problem.

    Release date:2016-08-28 04:47 Export PDF Favorites Scan
  • Deletion and Mutation of p16/mts1 Gene in Human Gastric Cancer of Different Periods

    ObjectiveTo determine the frequency and type of p16 gene homozygous deletion and mutation with the progression of human gastric carcinogenesis.MethodsPCR (polymerase chain reaction),SSCP (single strand conformation polymorphism) and DNA sequencing were performed on 50 operative tissues, which included 7 early gastric cancer and 43 advanced gastric cancer. In this group there were 36 male and 14 female patients aged 35 to 68,which included 30 welldifferetiated adenocarcinoma and 20 poordifferentiated carcinoma; 19 patients with lymph node metastases.ResultsTotal mutation frequency of p16 gene was 8.00%(4/50), including 14.29%(1/7) of early cancer and 7.00%(3/43) of advanced cancer,there was no significant difference between early and advanced cancer (P>0.05). In addition, p16 gene mutation was not related to site,location,grade of tumor differentiation and lymph node metastases, respectively. Total deletion frequency of p16 gene was 16.00%(8/50), of which 18.60%(8/43) was detected in advanced cancer, but no cases in early cancers. There was a significant difference between early and advanced cancer (P<0.05), and frequency p16 gene homozygous deletion was related to grade of tumor differentiation and lymph node metastases, respectively. Direct DNA sequencing displayed that 4 point mutations detected in 99,125,433,441 base, there were 3 missense mutation and 1 samesense mutation, no deletion or insertion was found. Conclusionp16 gene mutation is an early event in gastric carcinogenesis,it helps early diagnosis of human gastric carcinoma. p16 gene homozygous deletion is a late event in gastric carcinogenesis,it might relate to metastases and recurrence of gastric cancer.

    Release date:2016-08-28 05:12 Export PDF Favorites Scan
  • THE RELATION OF THE LOSS OF HETEROZYGOSITY AND MUTATION FOR nm23-H1 WITH THE INHIBITION OF METASTASIS IN COLORECTAL CARCINOMA

    The loss of heterozygosity and mutation for nm23-H1 gene in colorectal carcinomas were studied by Southern blot and RT-PCR-SSCP/silver staining sequencing. The rate of loss of heterozygosity for nm23-H1 was 29.63%. The cases of Duke’s stage D and distant metastatsis had higher frequency of the loss of heterozygosity. No mutation for nm23-H1 was found in colorectal carcinomas. These reaults indicate that the loss of heterozygosity for nm23-H1 may play a significant role in the malignant progression and distant metastasis in colorectal carcinomas.

    Release date:2016-08-29 09:18 Export PDF Favorites Scan
  • Detection of EGFR Exon 19 and 21 Mutations in Pleural Effusion from Non-Small-Cell Lung Cancer Patients by Mutant Enriched PCR Assay

    Objective To investigate the feasibility of detection of epidermal growth factor receptor ( EGFR) exon 19 deletions and exon 21 L858R mutations in pleural effusion fromnon-small-cell lung cancer ( NSCLC) patients by mutant enriched PCR assay. Methods The mutations of exon 19 and 21 of EGFR gene in pleural samples fromthirty NSCLC patients were analyzed using both the mutant-enriched PCR assay and the non-enriched PCR assay. Results Ten ( 33. 3% , 10/ 30) exon 19 deletions and five ( 16. 7% , 5/30) exon 21 L858R mutation were detected by the mutant-enriched PCR assay, while only 6 cases ( 20. 0% ) and 1 case ( 3. 3% ) were detected by the non-enriched PCR assay respectively. The difference of mutation detection rate of EGFR gene between the two methods was statistically significant ( P = 0. 032) . Mutations were detected in all of partial responders ( 2 /4) among the four patients who received gefitinib therapy. Conclusions Mutant-enriched PCR assay can detect EGFR exon 19 deletions and exon 21 L858R mutation in pleural effusion from NSCLC patients effectively, economically and accurately. It may be a valuable biomarker for gefitinib therapy in advanced NSCLC.

    Release date:2016-09-14 11:24 Export PDF Favorites Scan
  • QRDR Mutations in Fluoroquinolon-Resistant Pseudomonas aeruginosa and Its Relationship with the Usage of Antibiotics in Nosocomial Pneumonia

    Objective To investigate the mutations of quinolone resistance determinational region ( QRDR) in fluoroquinolon-resistant Pseudomonas aeruginosa strains isolated from patients with nosocomial pneumonia. Methods Eight-four Pseudomonas aeruginosa strains isolated from patients with nosocomial pneumonia in Xinhua Hospital during January 2006 to December 2007, from whom fluoroquinolon-resistant resisitant ( case) and fluoroquinolon-susceptible ( control ) Pseudomona aeruginosa were identified. The mutation of QRDR was tested by restriction fragment length polymorphism ( RFLP) and gene sequencing.The relationship between QRDR mutations and clinical prescription was analyzed. Results Mutation in QRDR was found in 42 isolates among the 50 fluoroquinlon-resisitant isolates( 84. 0% ) , while no mutation was found in fluoroquinlon-susceptible isolates. The mutation in GyrB Ser464 was found in 34 isolates ( 68. 0% ) . There was statistical difference in the usage of β-lactams between the GyrB-Ser464-mutated group and the non-GyrB-Ser464-mutated group( OR = 11. 3, P = 0. 003 and OR = 3. 5, P = 0. 023) , also in the time of fluoroquinolon usage before isolated ( P = 0. 038) . Conclusions The mutation of QRDR is contributing to fluoroquindor-resisitance of Pseudomona aeruginosa, most of which lies in GyrB Ser464.Abuse of β-lactams and fluoroquinolon may be the risk factors of mutation in GyrB Ser464.

    Release date:2016-09-14 11:25 Export PDF Favorites Scan
  • Clinical Significance of Epidermal Growth Factor Receptor Mutations from Patients with Non-Small Cell Lung Cancer

    Objective To evaluate the clinical significance of epidermal growth factor receptor EGFR) mutations in the treatment of non-small cell lung cancer ( NSCLC) . Methods Plasma DNAs solated fromblood specimens of 170 NSCLC patients, who were admitted in the First Affiliated Hospital of uangzhou Medical College from December 2005 to December 2007, were subjected to the test of EGFR utant-enriched PCR. The correlation of mutant detection with clinical characteristics was analyzed as well.Results Out of the total 170 patients, EGFR mutations were identified in 77 cases ( 77 /170, 45. 3% ) .EGFR mutations were more frequent in the patients with adenocarcinoma ( P lt; 0. 001) and in the nonsmokers P =0. 001) . In the 33 patients treated with gefitinib, those with mutations ( + ) showed a higher esponse rate and prolonged progression-free survival after the treatment compared with those with mutations( - ) ( P =0. 001 and 0. 001, respectively) . Conclusions EGFR active mutations can be specifically and ensitively detected by EGFR mutant enriched PCR assay. Plasma EGFR mutants detection is valuable in uiding clinical decision.

    Release date:2016-09-13 04:07 Export PDF Favorites Scan
  • PROGRESS IN RELATIONSHIP BETWEEN HERITABLE HYPERCOAGULABLE STATE AND AVASCULAR NECROSIS OF FEMORAL HEAD

    Objective To review the relationshi p between heritable hypercoagulable state (HHCS) and avascular necrosis of femoral head (ANFH). Methods The latest original articles about the relationshi p between HHCS and ANFH were extensively reviewed. Results Several genetic mutations which could cause HHCS, such as thrombophilic factor V G1691A gene, thrombophilic factor II G20210A gene, 5, 10-methylenetetrahydrofolate reductase C677T gene, plasminogen activator inhibitor 1 4G/5G, and tissue factor pathway inhibitor gene, may be genetic risks of ANFH. Conclusion HHCS may be a genetic cause of ANFH. Further studies are needed to confirm the relationship between HHCS and Chinese ANFH.

    Release date:2016-08-31 04:23 Export PDF Favorites Scan
  • COMPARATIVE STUDY ON OSTEOGENIC EFFECT OF BONE MARROW MESENCHYMAL STEM CELLS TRANSFECTED BY ADENOVIRUS-BONE MORPHOGENETIC PROTEIN 2-INTERNAL RIBOSOME ENTRY SITE-HYPOXIA INDUCIBLE FACTOR 1αmu AND BY BONE MORPHOGENETIC PROTEIN 2 SINGLE GENE

    ObjectiveTo compare the osteogenic effect of bone marrow mesenchymal stem cells (BMSCs) transfected by adenovirus-bone morphogenetic protein 2-internal ribosome entry site-hypoxia inducible factor 1αmu (Ad-BMP-2-IRES-HIF-1αmu) and by Ad-cytomegalovirus (CMV)-BMP-2-IRES-human renilla reniformis green fluorescent protein 1 (hrGFP-1) single gene so as to optimize the source of osteoblasts. MethodsBMSCs were separated and cultured from 1-month-old New Zealand white rabbit. The BMSCs at passage 3 were transfected by virus. The experiment was divided into 4 groups (groups A, B, C, and D) according to different virus: BMSCs were transfected by Ad-BMP-2-IRES-HIF-1αmu in group A, by Ad-CMV-BMP-2-IRES-hrGFP-1 in group B, by Ad-CMV-IRES-hrGFP-1 in group C, and BMSCs were not transfected in group D. The optimum multiplicity of infection (MOI) (50, 100, 150, and 200) was calculated and then the cells were transfected by the optimum MOI, respectively. The expression of BMP-2 gene was detected by immunohistochemistry staining after transfected, the expressions of BMP-2 protein and HIF-1α protein were detected by Western blot method. The osteogenic differentiation potential was detected by alkaline phosphatase (ALP) activity and Alizarin red staining. ResultsThe optimum MOI of groups A, B, and C was 200, 150, and 100, respectively. The expression of BMP-2 was positive in groups A and B, and was negative in groups C and D by immunohistochemistry staining; the number of positive cells in group A was more than that in group B (P ﹤ 0.05). The expression of BMP-2 protein in groups A and B was significantly higher than that in groups C and D (P ﹤ 0.05), group A was higher than group B (P ﹤ 0.05). The expression of HIF-1α protein in group A was significantly higher than those in the other 3 groups (P ﹤ 0.05), no significant difference was found among the other 3 groups (P ﹥ 0.05). ALP activity in groups A and B was significantly higher than that in groups C and D (P ﹤ 0.05), group A was higher than group B (P ﹤ 0.05). Calcium nodules could be seen in groups A and B, but not in groups C and D; the number of calcium nodules in group A was higher than that in group B (P ﹤ 0.05). ConclusionThe expression of BMP-2 and osteogenic effect of BMSCs transfected by Ad-BMP-2-IRES-HIF-1αmu (double genes in single carrier) are higher than those of BMSCs transfected by Ad-CMV-BMP-2-IRES-hrGFP-1 (one gene in single carrier).

    Release date:2016-08-31 05:39 Export PDF Favorites Scan
  • RELATIONSHIP BETWEEN MUTATION AT 1 573 FRAGMENT OF TNF RECEPTOR II GENE AND KELOID

    Objective To study the mutations at 1 573 fragment of TNF receptor II (TNFR-II) gene in patients with keloid. Methods The tissue DNA was extracted from 22 samples of keloids donated by 22 patients (6 males and 16 females, aged 18-53 years), and all keloids were examined and classified by pathologist. The peri pheral blood DNA was extracted from the same patients as the control. PCR was used to ampl ify the 1 573 fragment of TNFR-II gene from the keloid tissue DNA and peripheral blood DNA. The PCR products were sequenced directly and then compared with the GeneBankdata. Results All the concentration of the extracted DNA in trial were higher than 0.50 μg/μL and the purity (A260/A280) ofthe extracted DNA were higher than 1.5. It closed to the magnitude of the design DNA fragment by agarose gel electrophoresis examining, and corresponded with the test requirement. Mutations at 1 573 fragment of TNFR-II gene were detected in 13 out of 22 keloids. The mutation incidence was 59.1%. Among them, 9 had point mutation at codon 1 663, accounting 40.9%. No TNFR-II gene mutation was detected in all peripheral blood samples. There were significant difference between keloids DNA and peripheral blood DNA (P lt;0.01). The mutations involved point mutation, deletion and insertion as well as multisite and multitype. Conclusion There is a correlation between the mutation at 1 573 fragment of TNFR-II gene and keloid.

    Release date:2016-09-01 09:19 Export PDF Favorites Scan
  • EXPERIMENTAL STUDY ON FAS GENE DEATH DOMAIN MUTATIONS IN KELOID PEDIGREES

    Objective To detect gene mutations of Fas gene death domain (exons 7-9) in 2 Chinese keloid pedigrees and to investigatethe significance of Fas gene mutations in the keloid formation.Methods The samples were selected from keloid pedigrees A and B in 2005. The polymerase chainreaction and DNA sequencing analysis technique were used to detect the sequenceof exons 7-9 of Fas gene from keloid tissues of 2 male patients in pedigree A,their peripheral vein blood and their surrounding normal skin served as their own contrast, their spouses’ peripheral vein blood served as normal contrast, the peripheral vein blood of 2 patients in pedigree B served as a contrast between different keloid pedigrees.Results No gene mutations and single nucleotidepolymorphism in Fas gene exons 7, 8 were found in all samples from pedigrees A and B. But point mutations and single nucleotide polymorphism in Fas gene exon 9were identified in 11 bp and 53 bpin 2 keloid tissue samples from Chinese keloid pedigree A.Conclusion Fas gene point mutations maybe indicate some relations in Fas protein function and keloid formation.

    Release date:2016-09-01 09:23 Export PDF Favorites Scan
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