Biomedical subjects

Kai-Feng Pan

Publications and source records attributed to Kai-Feng Pan.

13 recordsLinked to original sources

PubMed2006

Eradication of H pylori infection in a rural population: one-day quadruple therapy versus 7-day triple therapy.

AIM: To compare the one-day quadruple therapy with a standard 7-d triple therapy for H pylori eradication in a rural population of China. METHODS: A total of 396 patients with (13)C-urea breath test positive for H pylori were assigned into two groups: 239 patients received one-day quadruple therapy (amoxicillin 2000 mg qid; metronidazole 500 mg qid; bismuth citrate 900 mg qid and lansoprazole 60 mg once daily) and 157 patients received 7-d standard triple therapy (amoxicillin 1000 mg bid; clarithromycin 500 mg bid and lansoprazole 30 mg bid). All the patients underwent a (13)C-UBT to assess the eradication of H pylori infection six weeks after treatment. RESULTS: Two hundred and twenty-nine patients completed the one-day therapy (95.8%) and 148 patients completed the 7-d therapy (94.2%). The one-day therapy eradicated H pylori infection in 64 patients (27.95%). In contrast, 103 patients (69.59%) were H pylori negative after the 7-d therapy (P < 0.01). CONCLUSION: This pilot study suggests there is no beneficial effect of the one-day therapy in treatment of H pylori infection compared with the 7-d standard therapy.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMed2006

[Feasibility of HLA-DRB1 matching by using DHPLC].

To study feasibility of HLA-DRB1 matching by using denatured high performance liquid chromatography (DHPLC), 20 pairs of DNA samples from donors and recipients of hematopoietic cell transplantation (HCT) for DRB1 matching and 2 pairs of samples from donors and recipient of HCT for DRB1 mismatching were studied by DHPLC and PCR-SSP. After being amplified and annealed slowly to produce heteroduplex, PCR products for exon 2 of DRB1 were detected by DHPLC to find matched or mismatched peaks in chromatogram. The results showed that DHPLC and PCR-SSP were consistant with matched or mismatched HLA-DRB1 typing. The results of DHPLC and PCR-SSP for matching were compared by using kappa test (kappa = 0.776, P = 0.00), which suggested DHPLC for HLA-DRB1 matching was in agreement with PCR-SSP. In conclusion, DHPLC for HLA-DRB1 matching is economic and convenient, moreover, will not be affected by unknown genes in HLA-DRB1 locus.

Base Sequence↗

PubMed2005

Frequent mutation related with overexpression of DNA polymerase beta in primary tumors and precancerous lesions of human stomach.

To explore whether DNA polymerase beta (pol beta) contributes to the malignant transformation of gastric mucosa, we examined pol beta in gastric tumor cell lines, primary tumors and precancerous lesions. Point mutations of pol beta were detected in 6 of 13 cell lines and 23 of 104 tissues including 35.0% (14/40) of gastric cancer (GC), 30.0% (3/10) of dysplasia (Dys), 28.6% (4/14) of intestinal metaplasia (IM) and 10.5% (2/19) of chronic atrophic gastritis (CAG), respectively. A frequent mutation was a T to C transition at nucleotide 889, which was observed in 4 GC cell lines, 7 GC, 2 Dys, and 2 IM. The level of pol beta expression in tumors was higher than that of their matched normal tissues and gradual changes from GC, Dys, CAG to IM. These results indicate that the mutation and overexpression of pol beta may influence the progression during gastric carcinogenesis.

Adult↗

PubMed2005

[First report on assessment of the status of engraftment after allogeneic hematopoietic stem cell transplantation by using denaturing high-performance liquid chromatography].

Monitoring engraftment of donor cells after allogeneic hematopoietic stem cell transplantation (allo-HSCT) is supposed to be important for the early diagnosis of graft failure or relapse of malignancy. Several techniques have been reported for this purpose. PCR-based assays analyzing polymorphic short tandem repeats (STR) as markers are attractive because they are sensitive and can be performed rapidly. The intent of this study was to test a novel approach for assessment of donor engraftment using denaturing high-performance liquid chromatography (DHPLC) combined with STR-PCR. The feasibility of this assay and the accuracy of semi-quantitative results were tested in-vitro by using serial DNA mixtures from unrelated individuals. The results showed that dilution experiments of the mock chimerism sample revealed a clear correlation between the percentage of donor or recipient DNA and the proportion of allele peak areas, with the limit of detection for a minor DNA percentage being 5%. Discrimination between donor and recipient was possible in all patients analyzed (n = 51) except for 5 patients whose pre-transplant samples were not available and identical twins in one case. STR results were the same as values obtained by capillary electrophoresis combined with fluorescence labeling multiply PCR. Results were also compared with data obtained with FISH analysis in a subgroup of patients receiving grafts from sex-mismatched donors or with PCR-detectable disease-specific gene products analysis. The results of the microsatellite analysis correlated well with the corresponding clinical findings. Full donor chimerism (FDC) were detected in all patients; decreasing values of donor chimerism were detected concomitantly with the appearance of relapse of disease in 3 patients. Samples from eight patients receiving HLA mismatched-haploidentical transplants from related donors together with cord blood transplants from unrelated donors were analyzed by this method. The results showed all 8 patients achieved FDC derived from related donors. It is concluded that this novel approach allows a rapid, sensitive, economical, auto-mated and non-isotopic STR-PCR testing, thus provides a reliable alternative for assessment of the status of engraftment after allo-HSCT.

Adolescent↗

PubMed2005

[Correlation of polymorphisms of UDP-glucuronosyltransferase 1A7 gene to genetic susceptibility of lung cancer].

BACKGROUND & OBJECTIVE: UDP-glucuronosyltransferase 1A7 (UGT1A7) plays an important role in detoxification through catalyzing combination of glucuronic acid and tobacco carcinogens, including benzo [alpha] pyrene, nitrosamine, and heterocyclic amine PhIP, therefore, inactivates the carcinogens. This study was to examine the correlation of polymorphisms of UGT1A7 gene to genetic susceptibility of lung cancer. METHODS: Polymorphisms of UGT1A7 gene at 12-131 and 208 sites in peripheral lymph cells of 312 patients and 317 age- and sex-matched controls were detected by polymerase chain reaction-denaturized high performance liquid chromatography (PCR-DHPLC) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP); the correlation of these polymorphisms to genetic susceptibility of lung cancer was analyzed. RESULTS: Compared with the UGT1A7*1/*1 genotype carriers, the UGT1A7*3/*1 genotype carriers had a 1.80-fold increased risk of lung adenocarcinoma [adjusted odds ratio (OR), 1.80; 95% confidence interval (CI), 1.03-3.12], the UGT1A7*3 genotype carriers had a 1.59-fold increased risk of lung adenocarcinoma (adjusted OR, 1.59; 95% CI, 0.96-2.63). The UGT1A7 polymorphisms had no correlation with risk of lung squamous cell carcinoma. CONCLUSION: UGT1A7 gene polymorphisms may increase the genetic susceptibility of lung adenocarcinoma in Chinese.

Adenocarcinoma↗

PubMed2004

Detection of frameshift mutations of RIZ in gastric cancers with microsatellite instability.

AIM: To study the frameshift mutations of the retinoblastoma protein-interacting zinc finger gene RIZ in gastric cancer with microsatellite instability, and to identify two coding polyadenosine tracts of RIZ. METHODS: Frameshift mutations at (A)8 and (A)9 tracts of RIZ were detected in 70 human gastric cancer (HGC) specimens by DHPLC and DNA sequencing. Microsatellite instability (MSI) status was assessed by two mononucleotide markers, BAT26 and BAT25, by means of denaturing high-performance liquid chromatography (DHPLC). RESULTS: In 70 HGC samples, 8 (11.4%) were found positive for instabilities at BAT26 and BAT25. In 7 of the 8 cases with instabilities at both BAT26 and BAT25 (MSI-H), 1 was unstable at BAT26 but stable at BAT25. Frameshift mutations were identified in 4 (57.1%) of the 7 samples with MSI-H in the (A)9 tract of RIZ without mutations in the (A)8 tract. In contrast, frameshift mutations were found in neither of the polyadenosine tracts in 63 samples of MSI-L or MSI stable tumors. Pro704 LOH detection in 4 cases with frameshift mutations did not find LOH in these cases. CONCLUSION: Frameshift mutations of RIZ may play an important role in gastric cancers with MSI.

DNA-Binding Proteins↗

PubMed2004

[Study of the relation between Cx31 gene and hereditary hearing impairment].

OBJECTIVE: To study the relation between hereditary nonsyndromic hearing impairment (NSHI) in Chinese and mutation in Connexin 31 (Cx31) gene and to explore the pathogenic mechanism. METHODS: Forty-seven pedigrees with hereditary NSHI, 38 Children with sporadic NSHI and cases of control were collected in present studies. The coding sequence of Cx31 gene was amplified by polymerase chain reaction (PCR), screened by denaturing high-performance liquid chromatography (DHPLC) and confirmed by direct sequencing. RESULTS: The mutation rate of heterozygous mutation C --> T at position 798 of Cx31 cDNA in patient group and in control were 14.1% (12/85) and 1% (1/100) respectively. Significant difference was found between the two group (P < 0.01). Heterozygous mutation G --> A at position 580 of GJB3 cDNA, which results in a missense mutation (A194T), was found in two members of one pedigree with autosomal dominant NSHI. The mutation was not found in numbers with normal hearing of this pedigree and controls. Heterozygous mutation G --> A at position 250 of Cx31 cDNA was found in one child with sporadic congenital NSHI. In our previous studies, Cx26 gene mutations have been screened among the patient with hereditary NSHI and sporadic NSHI and the control of our test, and two Cx26 gene mutations were found in two pedigrees. But the two NSHI pedigrees which were confirmed to have Cx26 gene mutation were not found to have Cx31 mutation. The patient and the control which were confirmed to have Cx31 gene mutations were not found to have Cx26 mutations. CONCLUSIONS: Cx31 gene was associated with nonsyndromic hearing impairment There was no cross and cooperative effect between Cx26 gene and Cx31 gene.

Adolescent↗

PubMed2004

[Studies of the relationship of HLA polymorphisms and the infection of H. pylori in the population of Linqu in Shandong Province].

In order to analyze the relationship of HLA polymorphisms and the infection of H. pylori in the population of Linqu County in Shandong Province, polymerase chain reaction with sequence-specific primers(PCR-SSP) was used to determine the alleles of HLA type I and II in 90 Hp-positive persons and 49 Hp-negative controls. The results showed that among the 68 alleles of HLA type I ,4 alleles were found significantly different between Hp-positive and Hp-negative population,while no significant difference was found among the 22 alleles of HLA type UI. Hp-positive persons had a lower allele frequency of A* 02 (OR=0.56, 95% CI=0.33 approximately 0. 94; P=0.029), B* 48 (OR=0.15, 95% CI=0.03 approximately 0.72; P=0. 007), CW* 08 (OR=0. 32, 95% CI=0.15 approximately 0.69; P=0. 003) and a higher allele frequency of CW* 15 (OR=5.11, 95% CI=0.63 approximately 40.90; P=0. 024) compared with Hp-negative controls. Our results indicated that the polymorphisms of HLA type I is involved in the genetic susceptibility of Hp infection in Linqu County,while the polymorphisms of HLA type I may have no relationship with the genetic susceptibility of Hp infection. It was shown that among the alleles of HLA type I , CW* 15 might be a susceptible gene of Hp infection while A * 02 ,B * 48 and CW* 08 might be protective genes.

Aged↗

PubMed2003

[Correlation between polymorphisms of interleukin-1beta and RN genes and risk of gastric carcinoma: a case-control study].

OBJECTIVE: To investigate the correlation between polymorphisms of interleukin-1beta and RN genes and risk of gastric carcinoma. METHODS: PCR and denaturing high-performance liquid chromatography (DHPLC) were used to analyze the IL-1beta-31 and -511 C/T polymorphisms and to genotype the IL-1RN penta-allelic variable number of tandem repeats (VNTR): of the DNA from the peripheral blood of 143 patients of gastric carcinoma, 97 from Linqu County, Shandong Province, and 46 cases from the specimen bank of Beijing Cancer Hospital, and 337 controls without gastric carcinoma from Linqu County, most of which suffered from other gastric diseases. RESULTS: IL-1-511 polymorphisms (carriers of IL-1beta-511T) were correlated with the increased risk of interstitial gastric carcinoma in both sexes (OR = 3.833, 95% CI: 2.282 approximately 6.439) and increased risk of diffuse gastric carcinoma in males (OR = 3.464, 95% CI: 1.394 approximately 8.608). The frequencies of IL-1beta-31 polymorphisms and IL-1IRN VNTR were not different between the gastric carcinoma group and the control group, IL-1beta-511 T carrier could be seen in the controls at different precancerous stages, for chronic atrophic gastritis (OR = 5.164, 95% CI: 2.661 approximately 10022), for interstitial metaplasia (OR = 5.093, 95% CI: 2.708 approximately 9.463), and for dysphasia (OR = 8.438, 95% CI: 3.939 approximately 18.073). CONCLUSION: IL-1beta-31 genotypes and. IL-2RN VNTR do not increase the risk of gastric carcinoma. The IL-1beta-511 T genotype increases the risk of gastric carcinoma in every precancerous stage.

Alleles↗

PubMed2003

[Relation between single nucleotide polymorphism in estrogen-metabolizing genes COMT, CYP17 and breast cancer risk among Chinese women].

OBJECTIVE: To test the hypothesis whether polymorphism in estrogen-metabolizing genes, COMT and CYP17, impacts on the risk of breast cancer among Chinese women. METHODS: COMT (Val158Met) and CYP17 (T1931C) polymorphisms were detected by PCR-based restriction fragment length polymorphism analysis in 250 breast cancer patients and 250 frequency-matched normal controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by unconditional logistic regression. RESULTS: COMT Met/Met genotype was found in 10.4% of breast cancer patients, which was significantly higher (P = 0.03) than that in controls (5.2%). Women with Met/Met genotype showed 2-fold increased risk for breast cancer (adjusted OR 2.1, 95% CI 1.1 - 4.5) compared with those with Val/Val or Val/Met genotypes. Stratified analysis showed that the elevated risk of breast cancer, associating with the COMT Met/Met genotype, was evident only among premenopausal women (adjusted OR 4.1, 95% CI 1.2 - 17.3) but not among postmenopausal women (adjusted OR 1.3, 95% CI 0.5 - 3.5). There was no significant difference in the distribution of CYP17 genotypes between breast cancer patients and the control subjects (P = 0.83). CONCLUSION: The allele encoding for low activity COMT, but not CYP17, may be a genetic risk factor for breast cancer among Chinese women.

Adult↗

PubMed2003

[Analysis of Lewis gene polymorphism in high and low incidence area of gastric cancer in Shandong province].

To explore the cause leading to the difference in incidence of gastric cancer between Linqu and Cangshan populations, Shandong Province,and to provide evidence for the possible mechanism of high incidence of gastric cancer in Linqu County,the distribution of T59G mutation in Lewis gene was screened between Linqu and Cangshan populations by PCR-sequencing.The frequency of individuals with T59G mutation was 34.5% in Linqu population and 31.6% in Cangshan population,respectively,with no significant difference, P>0.05, and OR is 1.14 (95% CI,0.59-2.19). This suggests that Linqu and Cangshan populations may share the same genetic background.T59G mutation of Lewis gene could not be used as a genetic marker for Linqu and Cangshan populations and is not relevant to the difference in incidence of gastric cancer between them.

English Abstract↗

PubMed2003

[Analysis of polymorphisms on Lewis blood group antigen related SE gene in the populations in Shandong with high-risk of gastric cancer and Beijing].

To study the relation between host genetic background and the susceptibility to H.pylori associated gastric cancer, PCR-sequencing and PCR-RFLP were used to screen SECRETOR gene polymorphisms in 142 subjects including 69 cancer patients and 73 non-cancer individuals from high-risk area of gastric cancer in Shandong and 93 control individuals from Beijing. Results showed that the difference in se(w)/se(w) distribution between non-cancer individuals and Beijing population was significant (P<0.01,OR is 3.06,95% CI,1.28-7.30), but that between cancer patients and non-cancer individuals was not with significance. SE gene polymorphism was not relevant to H.pylori infection. We concluded that Shandong population from high-risk area of gastric cancer shared a high distribution of se(w)/se(w) genotype,which could be considered as one of the genetic markers.

English Abstract↗

PubMed2002

Rapid screening mitochondrial DNA mutation by using denaturing high-performance liquid chromatography.

AIM: To optimize conditions of DHPLC and analyze the effectiveness of various DNA polymerases on DHPLC resolution, and evaluate the sensitivity of DHPLC in the mutation screening of mitochondrial DNA (mtDNA). METHODS: Two fragments of 16s gene of mitochondrial DNA (one of them F2 is a mutant fragment) and an A3243G mutated fragment were used to analyze the UV detection limit and determine the minimum percentage of mutant PCR products for DHPLC and evaluate effects of DNA polymerases on resolution of DHPLC. Under the optimal conditions, we analyzed the mtDNA mutations from muscle tissues of mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) and screened blindly for variances in D-loop region of mtDNA from human gastric tumor specimen. RESULTS: Ten A3243G variants were detected in 12 cases of MELAS, no alterations were detected in controls and these results were consistent with the results obtained by analysis of RFLP with ApaI. We also identified 26 D-loop variances in 46 cases of human gastric cancer tissues and 38 alterations in 13 gastric cancer cell lines. The mutation of mtDNA at 80 ng PCR products containing a minimum of 5% mutant sequences could be detected by using DHPLC with UV detector. Moreover, Ampli-Taq Gold polymerase was equally as good as the proofreading DNA polymerase (e.g., Pfu) in eliminating the false positive produced by Taq DNA polymerases. CONCLUSION: DHPLC is a powerful, rapid and sensitive mutation screening method for mtDNA. Proofreading DNA polymerase is more suitable for DHPLC analysis than Taq polymerase.

Case-Control Studies↗