50 000 bp)was extracted from frozen gastric cancer tissue and their corresponding normal samples and used for RLGS assay.The genome DNA was digested by methylation-sensitive restriction enzyme Not Ⅰ, and labeled by radioisotope ~(32)p,then separated by two-dimensional electrophoresis and autoradiography. Experimental conditions for each step were optimized step by step.DNA fragment sequences for the dots on scanning profile were identified according to the human RLGS database.Results RLGS assay was set up and used to get the RLGS profiles of the representative tested samples successfully.These profiles can display more than 1 200 available dots averagely,the profiles of high quality DNA sample can display more than 1 800 dots which is the average level at an excellent RLGS lab,discrepant dots which had weaken or enhanced signals and their sequence information were obtained.The result can be reproduced.Conclusion The RLGS assay is established,stabilized for detection of DNA methylation of tissue samples.

OBJECTIVETo establish a sensitive assay to detect methylation status of the critical 7862nt CpG site related to transcription of HPV16 E6 and E7 genes.

METHODSGenomic DNA of two HPV16-infected cell line SiHa and CaSki was extracted and modified by sodium bisulfite to convert the unmethylated Cs to Us (Ts in PCR products). The target sequence of HPV16 including the 7862nt CpG site was pre-amplified by PCR. Then, the methylation status of the 7862nt site was differentiated in a primer extension reaction with an HPV16-specific primer, and separated by DHPLC at 80 degrees C.

RESULTSThe primers without extension and with extension, whether matched to CpG or TpG, could be separated by DHPLC completely. The peak for ddTTP-extension products corresponding to the demethylated CpG site was observed at retention time 6.7 min in both cell lines. However, the peak for ddCTP-extension products representing the methylated CpG site could be detected at retention time 6.3 min in CaSki cell line only, which integrated with 499 methylated and one demethylated HPV16 copies.

CONCLUSIONThe established DHPLC-primer extension assay can be used to detect methylated and demethylated HPV16 copies simultaneously with a sensitivity up to 1/500 (0.2%).

Cell Line, Tumor ; Chromatography, High Pressure Liquid ; methods ; DNA Methylation ; DNA, Viral ; genetics ; Female ; Human papillomavirus 16 ; genetics ; isolation & purification ; Humans

OBJECTIVETo compare binding activity of different zinc finger domain of human Kaiso with methylated CpG.

METHODSpGEX constructs with different human Kaiso domain were generated and then corresponding fusion proteins were induced and purified. Electrophoretic mobility shift assays were applied to evaluate the binding activity of fusion proteins with methylated CpG.

RESULTSThe purified GST-KaisoZF fusion protein (without the POZ protein binding domain) could bind with methylated CpG probe specifically, but not for three or two zinc fingers without flanking domains.

CONCLUSIONHuman zinc finger protein Kaiso could bind with methylated CpG specifically, only in the assistance of the neighboring flank sequence of the zinc finger domain.

Base Sequence ; CpG Islands ; DNA Methylation ; Humans ; Transcription Factors ; genetics ; Zinc Fingers ; genetics

OBJECTIVETo setup a quantitative assay for detection of methylation of SNCG CpG island in human tissue samples.

METHODSMethylation status of the 16 tested CpG sites within the CpG island was analyzed by bisulfite-clone-sequencing for 2 gastric carcinoma cell lines, 2 normal gastric mucosa samples, and 2 pairs of primary gastric carcinomas and their corresponding non-neoplastic tissues, respectively.

RESULTSThe methylation of -88 and other four CpG sites was well correlated with the methylation of the overall CpG island. Thus, a combined bisulfite-restriction assay (COBRA) was developed based on the enzyme AciI, which digested the only one GCGG sequence in the PCR products of the methylated CpG island, but not the GTGG in the demethylated one. The digested fragments (144 bp and 85 bp) and undigested fragment (229 bp) could be completely separated by denaturing high performance liquid chromatography (DHPLC). According to the peak areas of these fragments, the proportion of the methylated copies of the SNCG CpG island was calculated easily. The result of the COBRA-DHPLC assay was reproducible and consistent with that of clone-sequencing.

CONCLUSIONA COBRA-DHPLC assay is setup successfully for quantification of methylation of the SNCG CpG island.

Cell Line ; Cell Line, Tumor ; Chromatography, High Pressure Liquid ; CpG Islands ; DNA Methylation ; Humans

OBJECTIVETo detect the therapeutic effect of selenium-enriched garlic (SeG) on chronic gastritis.

METHODSChronic gastritis was induced of the glandular stomach of male Mongolian Gerbils via gastric instillation of H. pylori TN2 strain once every 4 days for 5 consecutive times followed by random classification into six groups. Fresh SeG suspension was administrated daily at dosages of 4.70, 1.5, 0.47, 0.15 g.kg(-1).d(-1) for four weeks. The gerbils in the positive control group were treated with omeprazole, clarithromycin, and amoxicillin for one week. The gerbils were killed for pathological examination four weeks after SeG-treatment.

RESULTSChronic gastritis (CAG), low-grade dysplasia or gastric intraepithelial neoplasia (DYS/GIN) were observed among 77% and 38.5% of the 13 H. pylori-treated animals in the negative control group, respectively; whereas 40% and 26.7% in the positive control group (n = 15), respectively. The incidences of CAG and DYS/GIN in the SeG groups (n = 21 - 27) were reduced dose-dependently, 16.7% - 38.7% and 11.1% - 14.3% for CAG and DYS/GIN, respectively.

CONCLUSIONSeG administration inhibits the development and progression of CAG induced by H. pylori remarkably.

Animals ; Chronic Disease ; Disease Models, Animal ; Garlic ; Gastritis ; drug therapy ; microbiology ; Gerbillinae ; Helicobacter Infections ; drug therapy ; Helicobacter pylori ; Male ; Phytotherapy ; Selenium ; therapeutic use

OBJECTIVETo investigate relationship between methylation status of the APC and Bikunin CpG islands and clinicopathological characteristics of breast carcinomas.

METHODSThe methylation status of APC and Bikunin CpG islands in 152 sporadic breast carcinoma samples were analyzed by methylation specific PCR.

RESULTS40.8% of breast carcinomas examined showed methylated signals for the APC. The methylation frequency of APC was significantly correlated to the tumor size (chi(2) = 4.041; P = 0.044), but not to patients' age, pathologic type of tumor, clinical stage, histological grade, lymph node metastasis and the status of estrogen or progestogen receptor. In addition, 24.6% of carcinoma samples examined revealed strong methylated signals for Bikunin. No significant correlation was found between the aberrant methylation of Bikunin and the clinicopathological characteristics of sporadic breast carcinomas.

CONCLUSIONThe aberrant methylations of APC and Bikunin are frequent events during breast carcinogenesis. APC methylation might play a role in the progression of breast cancer.

Breast Neoplasms ; genetics ; pathology ; CpG Islands ; DNA Methylation ; DNA, Neoplasm ; genetics ; Female ; Follow-Up Studies ; Humans

OBJECTIVETo investigate the effects of methylation status of CpG islands of endogenous E-cadherin (CDH1) gene on the promoter activity of corresponding genes in reporter assays.

METHODSThe methylation statuses of CpG island of CDH1 in 8 different cell lines were detected by methylation-specific PCR. CDH1 protein was analyzed by Western blotting. Two sets of pGL3 reporter vectors with different genotypes/haplotypes of the CDH1 promoter were constructed [ pGL3-A(-73)/-C(-73) pGL3-H1/-H4] and used to transfect these cell lines. The differences between these promoter reporter vectors were analyzed by t-test.

RESULTS(1) CDH1 CpG island was unmethylated in AGS, MCF7, MKN74, and PC-3 cell lines, expressed in MCF7, MKN74, and PC-3, but not in AGS. Expression of CDH1 was silenced by methylation in HeLa, BGC823, A549, and RKO cell lines. (2) In the four CDH1-unmethylated MCF7, MKN74, PC-3, and AGS cell lines, the promoter activities of pGL3-C(-73), (as 0.78 +/- 0.10, 0.17 +/- 0.01, 0.11 +/- 0.01, 1.19 +/- 0.18) were significantly higher than those of pGL3-A(-73) (as 0.30 +/- 0.08, 0.07 +/- 0.01, 0.07 +/- 0.01, 0.39 +/- 0.04) (t values are -6.298, - 12.349, -8.128, -7.388, and P <. 0.1). However, in the four CDH1-methylated HeLa, BGC823, A549, and RKO cell lines, the promoter activity of pGL3-C(-73) (as 0.09 +/- 0.02, 0.13 +/- 0.02, 0.05 +/- 0.01, 0.01 +/- 0.00) was significantly lower than that of pGL3-A(-73) (as 0.16 +/- 0.01, 0.25 +/- 0.01, 0.11 +/- 0.03, 0.03 +/- 0.00) (t valued at 5.958, 11.189, 3.661, 13.866, and P<0.05). (3) In the unmethylated MKN74 and methylated RKO cell lines, the promoter activities of pGL3-H1/-H4 were obviously and contrarily different (as 1.57 +/- 0.23/0.94 +/- 0.06 and 0.38 +/- 0.02/0.50 +/- 0.04, t values were 4.577 and -4.915, P values were 0.010 and 0.003).

CONCLUSIONThe methylation status of CpG island of the target gene in the tested cell lines affects the promoter activity in Reporter Assay significantly. The most active one may be the most suppressive one.

Cadherins ; genetics ; metabolism ; Cell Line, Tumor ; CpG Islands ; genetics ; DNA Methylation ; Flow Cytometry ; Genes, Reporter ; Humans ; Luciferases ; genetics ; Methyl-CpG-Binding Protein 2 ; genetics ; Promoter Regions, Genetic

OBJECTIVETo investigate the relationship between point mutation of penicillin-binding protein gene (pbp) and amoxicillin resistance (AMOgamma) of Helicobacter pylori (H. pylori) as well as to compare the protein profiles under proteomic technology to get the candidate resistance-related proteins.

METHODS(1) AMOgamma strains were selected from the sensitive H. pylori strain 26695 by serial passage technique in vitro. (2) Point mutations of five putative resistance genes (HP0597, HP1565, HP1542, HP1556, and HP0160) were analyzed by denaturing high-performance liquid chromatography (DHPLC) and DNA sequencing. (3) Proteins samples were separated by two-dimensional electrophoresis (2-DE). Protein profiles were compared between the AMOgamma strain obtained in vitro and its sensitive parent strain 26695. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was performed to identify the proteins of interest. The proteins were searched by software MASCOT and identified by peptide fingerprint map using the program MS-FIT of Protein Prospect.

RESULTS(1) An AMOgamma strain (MIC 8 microg/ml) was obtained. Complete loss of the resistant phenotype was observed after cultivation in the absence of AMO or storage at - 80 degrees C. (2) DHPLC and Sequencing result showed no point mutations in five pbp genes in the AMOgamma strain when compared with the corresponding PCR products from its parent strain 26695. (3) Protein profiling showed that eleven protein spots were differently expressed between 26695 and the AMOgamma strain. Of these protein spots in the AMOgamma strain, two new spots (Spot 1 and Spot 2) were observed with one (Spot 3) was up-regulated three-fold and the remained ones (Spot 4-11) were down-regulated.

CONCLUSIONAMO resistance of H. pylori might be resulted from, unstable phenotype change rather than point mutations of pbp genes. These differentially regulated proteins in AMOgamma strain might play a role in development of resistance to AMO in H. pylori.

Amoxicillin ; pharmacology ; Anti-Bacterial Agents ; pharmacology ; Bacterial Proteins ; genetics ; metabolism ; Chromatography, High Pressure Liquid ; Drug Resistance, Bacterial ; genetics ; Electrophoresis, Gel, Two-Dimensional ; Helicobacter pylori ; drug effects ; genetics ; metabolism ; Point Mutation ; genetics ; physiology ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

OBJECTIVETo test the efficacy of kyphoplasty using an enhanced balloon expander in restoring the height of vertebral compression fractures (OVCF).

METHODSFifteen lumbar vertebral bodies (L1-L5) were harvested from 3 young male fresh cadavers and separated into individual vertebral bodies with the bilateral pedicles of the vertebral arch removed. Before operation, plain X-ray films of all the vertebral bodies were obtained. All the vertebral bodies were compressed lengthwise to approximately 80% of their original heights using a universal material-testing machine to result in compression fractures. Post-compression vertebral bodies were then repaired using an enhanced balloon expander, and the delivery of the bone cement into the vertebral bodies was observed. The heights of the anterior and posterior borders of the vertebral bodied were measured before and after compression as well as after kyphoplasty.

RESULTSThe inflation of the balloon expander averaged 2.95-/+0.18 ml and the pressure was 122.67-/+27.89 psi (1 psi=6895 Pa). Kyphoplasty resulted in significant restoration of the vertebral body height lost due to the compression (P<0.01).

CONCLUSIONKyphoplasty using an enhanced balloon expander may restore vertebral body height damaged by compression and correct the kyphotic deformity. The balloon expander can be a effective and economic choice for kyphoplasty for its relatively low cost.

Adult ; Bone Cements ; Cadaver ; Catheterization ; Fractures, Compression ; etiology ; surgery ; Humans ; Lumbar Vertebrae ; injuries ; surgery ; Male ; Spinal Fractures ; complications ; surgery ; Tissue Expansion Devices ; Vertebroplasty ; instrumentation ; methods

OBJECTIVETo observe the alterations of saliva nitrate and nitrite level in patients with oral candidiasis.

METHODSParotid saliva and whole saliva were collected from 33 patients and 34 healthy volunteers. Concentrations of nitrate and nitrite in saliva were determined by high-performance liquid chromatography. Follow-up observation was performed on 10 patients after treatment. The data were statistically analyzed with independent-samples t test or paired-samples t test at alpha = 0.05.

RESULTSThere was significant increase of the concentrations and secretion rate of parotid saliva nitrate in patient group as compared with controls: (49.70 +/- 0.50) vs (21.51 +/- 0.60) mg/L (t = 2.692, P = 0.009) and (27.71 +/- 0.50) vs (12.55 +/- 0.60) microg/min (t = 2.554, P = 0.013), respectively. Significantly increased concentrations and secretion rate of nitrate and nitrite [nitrate: (6.46 +/- 0.94) vs (1.11 +/- 0.70) mg/L (t = 3.792, P = 0.000); nitrite: (8.48 +/- 0.58) vs (3.39 +/- 0.53) mg/L (t = 2.888, P = 0.005); nitrate secretion rate: (10.57 +/- 0.91) vs (2.10 +/- 0.74) microg/min (t = 3.464, P= 0.001); nitrite secretion rate: (13.91 +/- 0.55) vs (6.42 +/- 0.58) microg/min (t = 2.397, P = 0.020)] were revealed in whole saliva of patients group. Significantly decreased nitrate and nitrite levels were also observed in patients after treatment, especially the changes of parotid saliva nitrate secretion rate [(37.50 +/- 0.50) vs (14.34 +/- 0.64) microg/min (t = 3.142, P = 0.012)], whole saliva nitrate [(14.29 +/- 1.01) vs (2.59 +/- 1.03) mg/L (t = 3.475, P = 0.007)] and whole saliva nitrate secretion rate [(25.97 +/- 0.93) vs (4.12 +/- 1.00) microg/min (t = 3.922, P = 0.003)].

CONCLUSIONThe present study revealed the significant increase of salivary nitrate and nitrite level in patients with oral candidiasis is considered to be associated with the host defense reaction.

Adult ; Aged ; Candidiasis, Oral ; metabolism ; Case-Control Studies ; Female ; Humans ; Male ; Middle Aged ; Nitrates ; metabolism ; Nitrites ; metabolism ; Saliva ; secretion ; Young Adult