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Min Gao

Publications and source records attributed to Min Gao.

At least 37 records · Page 2Linked to original sources
PubMed2006

Systematic evaluation of association between the microsomal glutathione S-transferase 2 common variation and psoriasis vulgaris in Chinese population.

Several recent studies have demonstrated the possible involvement of the microsomal glutathione S-transferase 2 (MGST2) gene in the pathogenesis of psoriasis. The objectives of this work are to determine whether the genetic polymorphisms of the MGST2 gene were associated with an increased risk of psoriasis in Chinese patients. We first characterized the linkage disequilibrium pattern within MGST2 and identified single-nucleotide polymorphisms (SNPs) for tagging common genetic variants. Genotype- and haplotype-based analyses were then performed by genotyping the Tag SNPs in a large-scale sample of cases and controls. We characterized the linkage disequilibrium pattern within MGST2 using 12 densely distributed SNPs and identified 6 SNPs for tagging common genetic variants. We then performed an association analysis by genotyping the six SNPs in 552 cases and 384 controls, but none of the genotype- and haplotype-based analyses revealed significant evidence for association. We also performed family-based association analysis by genotyping the six SNPs in 95 trios; no evidence for association was identified. Our comprehensive genetic analysis of MGST2 common variants in a large Chinese sample of psoriasis did not provide any supporting evidence for MGST2 to be the susceptibility gene within the PSORS9 locus.

Adolescent↗
PubMed2006

True versus reported waiting times for valvular aortic stenosis surgery.

OBJECTIVES: To produce a universally accepted waiting time definition for cardiovascular surgery, present the rationale for this definition, and compare data on current waiting times in British Columbia based on this definition versus the current definition in patients waiting for aortic stenosis surgery. STUDY DESIGN: The present study is a retrospective data analysis. SETTING: The fixed-dollar, single-payer health care delivery system in British Columbia. PATIENTS: All residents of British Columbia who were at least 22 years of age and who were placed on a waiting list for aortic valve surgery with the diagnosis of aortic stenosis between January 1, 1991, and December 31, 2000, were eligible for the present study. INTERVENTIONS: Dates of physician visits, procedures and surgery were obtained from the British Columbia Cardiac Registries and Medical Services Plan databases. True waiting times from physician visits to procedures and surgery were calculated. RESULTS: Of the 2516 patients booked for aortic valve surgery with a primary diagnosis of aortic stenosis, 2237 subjects (88.9%) were eligible for analysis after exclusions. The eligible patients ranged in age from 22 to 95 years, and 36.8% were female. The true median waiting time was 243 days (148 days [25th percentile], 397 days [75th percentile]), which was 3.2 times the interval currently reported as the waiting time (75 days [42, 127]). Thirty-nine patients died while waiting for surgery. Patients used more resources while waiting for surgery than after surgery. CONCLUSIONS: True waiting times for surgery for aortic stenosis in British Columbia are significantly longer than reported waiting times. The authors propose that the wait list time for cardiovascular surgery be redefined as "the time interval between the patient's first contact with a medical care provider with symptoms or signs which ultimately lead to cardiovascular surgery and the date of that surgery".

Adult↗
PubMed2006

[Effects of chemotherapy in recurrent endometrial carcinoma].

OBJECTIVE: To explore the effects of chemotherapy in recurrent endometrial carcinoma. METHODS: A retrospective study was carried out on the clinical data of 20 cases of recurrent endometrial carcinoma hospitalized from May. 1992 to Jun. 2002. RESULTS: The recurrence rate of these 20 cases was 11.0%. The recurrence occurred (17 +/- 10) months after the first therapy. Eleven of the 20 patients (55.0%) had accepted chemotherapy with (6 +/- 4) courses and were followed up for (17 +/- 16) months after the second therapy. Fifteen cases (75.0%) died of cancer, 4 cases survived with tumor, and only 1 case (5.0%) was tumor-free. Univariate model revealed that chemotherapy and number of chemotherapy course were related with the prognosis (P = 0.0146, P = 0.0353). Radiotherapy affected the prognosis too (P = 0.0414). But pathologic subtype, stage, tumor cell differentiation, age, recurrent time, surgery, chemotherapy scheme, drug infusion way , and endocrine therapy had no relation with the prognosis (P = 0.5517, 0.5763, 0.1879, 0.880, 0.453, 0.0672, 0.0795, 0.5956, and 0.2035). Multivariate model revealed that chemotherapy had influence on the prognosis (beta = -1.349, OR = 0.259, P = 0.026). CONCLUSION: Combined treatment raises the survival of the recurrent endometrial carcinoma patients, in which chemotherapy plays a leading role and influences the prognosis remarkably.

Combined Modality Therapy↗
PubMed2006

Convergence of Itch-induced ubiquitination with MEKK1-JNK signaling in Th2 tolerance and airway inflammation.

The immune system is capable of mounting robust responses against invading pathogens but refrains from attacking self. Many studies have focused on tolerance induction of Th1 cells, whose failure results in development of autoimmune diseases. However, the molecular mechanisms governing tolerance induction in Th2 cells and its relation to allergic responses remain unclear. Here we used both in vivo and in vitro protocols to demonstrate that Th2 cells either containing a mitogen and extracellular kinase kinase 1 (MEKK1) mutant or lacking JNK1 or the E3 ubiquitin ligase Itch cannot be tolerized. In a mouse allergic model, injection of high-dose tolerizing antigen failed to block the development of airway inflammation in Itch-/- mice. This study suggests that MEKK1-JNK signaling regulates Itch E3 ligase-mediated tolerogenic process in Th2 cells. These findings have therapeutic implications for allergic diseases.

Animals↗
PubMed2006

Five mutations of ATP2A2 gene in Chinese patients with Darier's disease and a literature review of 86 cases reported in China.

Darier's disease (DD) is an autosomal dominantly inherited skin disorder characterized by loss of adhesion between epidermal cells (acantholysis) and abnormal keratinization. To date, at least 140 mutations in the ATP2A2 gene have been identified as the genetic basis of DD. Here we reported three familial and two sporadic Chinese DD patients totally with four missense mutations (N767D, M494I, M494L, C318F) and one splice-site mutation (1288-6A-->G) in ATP2A2 gene, and presented a literature review of DD cases reported in China since 1989. Our data add new variants to the repertoire of ATP2A2 gene in DD and confirms that most mutations in the ATP2A2 gene are private and missense type. Likewise, the literature review indicates that DD is not uncommon in China and presents more information about genotype-phenotype correlations.

Asian People↗
PubMed2006

Growth and activation of PI-3K/PKB and Akt by stromal cell-derived factor 1alpha in endometrial carcinoma cells with expression of suppressor endoprotein PTEN.

BACKGROUND: Mutation or deletion in the phosphatase and tensin homologue deleted on chromosome ten (PTEN) gene has been identified as an important cause of endometrial carcinoma; stromal cell derived factor-1alpha (SDF-1alpha) exerts growth-promoting effects on endometrial cancer cells through activation of the PI-3 kinase/Akt pathway and downstream effectors such as extracellular-responsive kinase (ERK). In this study, a plasmid containing the PTEN gene was transfected into Ishikawa cells to investigate the difference in growth and signal transduction between Ishikawa-PTEN and Ishikawa cells after SDF-1alpha stimulation, and to study mechanisms of the involvement of PTEN protein in endometrial carcinoma development. METHODS: Ishikawa cells were transfected with a plasmid (pLXSN-PTEN) containing the PTEN gene and a plasmid (pLXSN-EGFP) with enhanced green fluorescent protein (EGFP). Cells were then screened to obtain Ishikawa-PTEN cells and Ishikawa-neo cells that can both stably express PTEN protein and EGFP. Expression of PTEN protein, phosphorylation levels of AKT and ERK (pAKT and pERK) and growth differences in Ishikawa-PTEN, Ishikawa-neo and Ishikawa cells before and after SDF-1alpha stimulation were then determined by Western blots and MTT assays. RESULTS: Western blot analysis showed that Ishikawa cells produced PTEN after transfection with the PTEN gene. At 15 minutes after SDF-1alpha stimulation, the pAKT level of Ishikawa-PTEN cells was lower than that of Ishikawa-neo cells and Ishikawa cells. There was no significant difference in pERK levels among the three cell lines. The positive effect of SDF-1alpha on Ishikawa-PTEN cells growth was markedly less than the effect on Ishikawa-neo and Ishikawa cells. However, in the absence of SDF-1alpha stimulation (baseline), the pAKT level in Ishikawa-PTEN cells was less than that in Ishikawa cells. There was a significant difference in growth between the Ishikawa-PTEN cells and the Ishikawa-neo cells. CONCLUSIONS: PTEN gene transfection can regulate the level of pAKT but not pERK in Ishikawa-PTEN cells. PTEN protein may suppress the growth-promoting effect of SDF-1alpha on endometrial carcinoma by inhibiting the PI-3K/AKT signal transduction pathway.

Cell Line, Tumor↗
PubMed2006

Activation of the E3 ubiquitin ligase Itch through a phosphorylation-induced conformational change.

The E3 ubiquitin (Ub) ligase Itch is a critical regulator of T helper 2 (Th2) cytokine production through its ability to induce Ub-dependent JunB degradation. After T cell receptor engagement, Itch undergoes JNK1-mediated phosphorylation that greatly enhances its enzymatic activity. To investigate how phosphorylation activates an E3 Ub ligase we have identified the JNK1 phosphorylation sites within Itch as S199, S232, and T222, which are located within a Pro-rich region. Phosphorylation of these sites is necessary and sufficient for disrupting an inhibitory interaction between the WW domain of Itch and its catalytic HECT (Homologous to E6-AP C Terminus) domain and induces a conformational change that greatly enhances the catalytic activity of Itch, a HECT E3 ligase found to be directly activated upon its phosphorylation.

Cell Line↗
PubMed2006

Acanthamoeba keratitis: clinical characteristics and management.

OBJECTIVE: To review the clinical characteristics, treatment, and outcome of patients with Acanthamoeba keratitis (AK). DESIGN: Retrospective, noncomparative, interventional case series. PARTICIPANTS: Twenty consecutive patients with AK were referred to the Beijing Tongren Hospital, Capital University of Medical Science, China. METHODS: Retrospective analysis of medical records from 20 consecutive patients with AK between December 1, 1997 and March 30, 2003. Risk factors, laboratory investigations, clinical manifestations, treatments, and outcomes were analyzed. MAIN OUTCOME MEASURES: Best-corrected visual acuity (BCVA) at the end of follow-up. RESULTS: Of the 20 patients presented in this series, 12 patients were students and 6 were farmers. Risk factors included contact lens wear (12/20) and trauma (6/20). Corneal ulceration, diffuse stromal infiltration, and ring infiltration were the main clinical manifestations. The diagnosis of all patients was based on the laboratory investigation. Smear and culture positive specimens were 19 of 20 and 12 of 20, respectively. Images of cysts were demonstrated with confocal microscopy in 4 patients. Treatment was combined instillation of chlorhexidine (0.02%), neomycin (0.5%), metronidazole (0.4%), and/or lesion cauterization with chlorhexidine (1%), and corneal lesion debridement. The mean duration of therapy was 70 days (range, 18-150 days). Nineteen lesions healed with scar formation. The BCVA was better or equal to 20/100 in 7 eyes. CONCLUSIONS: Early diagnosis of AK is the key challenge in clinical practice. The combined use of antiacanthamoeba agents, debridement, and cauterization may be a best choice of treatment for patients who are diagnosed early in the course of their disease.

Acanthamoeba Keratitis↗
PubMed2006

External validation of a percutaneous coronary intervention mortality prediction model in patients with acute coronary syndromes.

BACKGROUND: The recently published Michigan outcome prediction model (MM) for inhospital mortality was developed and validated on a series of consecutive patients undergoing percutaneous coronary intervention (PCI). Our purpose was to externally validate the performance of the MM in 2 separate cohorts of patients with acute coronary syndrome (ACS) undergoing PCI in Canada. METHODS: A validation of the MM and development of an extended MM were performed on data describing 10,050 patients from the APPROACH prospective cohort study between January 1995 and December 2000. Performance of both models was assessed on an external data set of 3259 PCI cases from the British Columbia Cardiac Registries. Only patients with a diagnosis of ACS were included in the study. RESULTS: The original MM predicted death rates ranging from 0.1% to 60.6%, but lacked accuracy to predict inhospital mortality as severity increased. The extended MM predicted death rates more widely from 0.0% to a high of 91.0% with better accuracy to predict inhospital death in patients with ACS undergoing PCI. The areas under the receiver operating characteristic curve for the MM and the extended MM on the external validation data set were 0.93 and 0.95, respectively. CONCLUSION: The MM predicts death after PCI in patients with ACS and identifies a clear gradient of risk. However, the enhanced MM developed specifically for the subset of patients with ACS demonstrated better prediction and cross-validated performance. These prediction rules can be useful for risk-adjustment analyses and for prognostication for individual patients.

Aged↗
PubMed2006

Changing outcomes of coronary revascularization in British Columbia, 1995-2001.

OBJECTIVES: To examine outcomes following all first coronary revascularization procedures, isolated coronary artery bypass graft surgery (CABG) and percutaneous coronary intervention (PCI) on British Columbia (BC) resident adults from 1995 to 2001. METHODS: CABG and PCI data were obtained from the BC Cardiac Registry, and mortality data were obtained from the BC Vital Statistics Agency. Analysis was performed by annual cohorts, and the rates reported are unadjusted. RESULTS: An increasing percentage of revascularization procedures was performed with PCI (62% in 1995 to 73% in 2001; P<0.001) due to the increased use of PCI procedures. Except in emergent cases, 30-day mortality improved after PCI (1.8% to 1.1%; P=0.02) and CABG (1.8% to 1.2%; P=0.01). Emergent cases accounted for 9.0% of PCIs and 2.7% of CABGs, the percentage treated by CABG decreasing from 14.5% in 1995 to 7.5% by 2001 (P<0.001). Mortality rates among emergent cases was higher at 30 days, with no trend in PCI mortality (12%) but a substantial reduction in 30-day mortality after CABG (28% to 10%; P=0.003). One-year survival free from repeat revascularization following PCI increased from 73% in 1995 to 83% in 2001 (P<0.001) and from 94% to 95% (P<0.005) following CABG. CONCLUSIONS: Improvements in procedure-related mortality observed in trials have extended to clinical practice. With respect to emergent cases, an increasing proportion were treated by PCI with no change in PCI mortality but associated with a drop in surgical mortality. There has been a consistent and substantial drop in the need for repeat procedures within one year for patients selected for PCI.

Adult↗
PubMed2006

A novel MGST2 non-synonymous mutation in a Chinese pedigree with psoriasis vulgaris.

A balanced translocation was recently identified in a German psoriasis patient. One of the breakpoints was mapped immediately upstream of the microsomal glutathione S-transferase 2 (MGST2) gene, suggesting it as a candidate gene. Here, we report the identification of a novel non-synonymous mutation in MGST2 by a comprehensive sequence analysis of MGST2's coding region in Chinese psoriasis samples. We demonstrate that this mutation co-segregated with the disease phenotype within a Chinese family affected with psoriasis vulgaris and is predicted to have an impact on the normal function of MGST2 protein. However, the mutation was absent in 551 additional cases and 384 healthy Chinese controls. While requiring independent confirmation, our results suggest that this rare mutation could play a causal role in a small subset of psoriasis individuals.

Adult↗
PubMed2006

Inversa acne (hidradenitis suppurativa): a case report and identification of the locus at chromosome 1p21.1-1q25.3.

Acne inversa (hidradenitis suppurativa) is a chronic relapsing inflammatory skin disease characterized by recurrent draining sinuses and abscesses, predominantly in skin folds that carry terminal hairs and apocrine glands. The genetic basis for this disease is unknown. In this study, we performed a genome-wide scan in a four-generation Chinese family to map the chromosome location of the responsible gene. We first identified a locus at chromosome 1p21.1-1q25.3 with the maximum logarithm of odds (LOD) score of 3.26 at the marker D1S2624 (at recombination fraction=0.00). The other two-point LOD scores >/=3 were observed at markers D1S2695, D1S2726, D1S252, and D1S2777. Haplotype analysis localized this locus to a 76 Mb region flanked by D1S248 and D1S2711. This is the first locus for the inversa acne and will be a starting point towards understanding the molecular mechanisms of this disease.

Adult↗
PubMed2006

Diverse phenotype of Brooke-Spiegler syndrome associated with a nonsense mutation in the CYLD tumor suppressor gene.

Brooke-Spiegler syndrome (BSS) is an autosomal dominant disease characterized by cylindromas, trichoepitheliomas and occasionally spiradenomas. The disease gene was mapped to 16q12-13, and mutations in the CYLD gene were identified in families with BSS. In the present report, we describe a large consanguineous Chinese family with BSS showing an intra-family phenotypic variability. Clinically, some affected individuals only revealed discrete small skin-coloured tumors whereas the proband showed an expansion of multiple large tumors on the back of nose and numerous dome-shaped papules on her scalp. Histologically, both trichoepitheliomas and cylindromas were found in the affected individuals. By sequence analysis, we identified a recurrent mutation 2272C>T (R758X) of the CYLD gene in the affected individuals of this family, which was previously identified in other ethnic families with familial cylindromatosis. Our result provided additional information for phenotype-genotype correlation in BSS.

Adult↗
PubMed2006

[Pathogenic free-living amoebic keratitis in China].

The first case of acanthamoebic keratitis in China was reported by JIN Xiu-ying et al in 1992. Over past ten years, extensive researches on this vision-threatening keratitis in the etiology, biology, specimen culture and preservation of pathogen, pathogenesis and virulence, animal model, pathology and immunology, clinical diagnosis and management have been carried out.

Acanthamoeba Keratitis↗
PubMed2006

[Regulatory effect of 17beta-estradiol on expression of orphan nuclear receptor ERRalpha in endometrial carcinoma cell lines].

BACKGROUND & OBJECTIVE: Estrogen receptor-related receptor alpha (ERRalpha), a member of the subfamily of orphan nuclear receptors, could compete with estrogen receptor alpha (ERalpha) to bind the same target genes and interfere in ER signal pathway. Therefore, it might be associated to the tumorigenesis of endometrial carcinoma. This study was to explore the regulatory effect of 17beta-estradiol (17beta-E(2)) on ERRalpha expression, and to elucidate the relationship between ERRalpha and ER signal pathway in endometrial carcinoma cell lines. METHODS: ERalpha-positive cell line Ishikawa and ERalpha-negative cell line HEC-IA were treated with different concentrations of 17beta-E(2) (1x10(-10) mol/L, 1x10(-8) mol/L, and 1x10(-6) mol/L) for 24 h and 48 h, respectively. The levels of ERRalpha mRNA and protein were examined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. 17beta-E(2) (1x10(-8) mol/L) and complete ER inhibitor ICI182,780 (1x10(-6) mol/L) were given concomitantly to observe the change of ERRalpha expression. RESULTS: The levels of ERRalpha mRNA and protein in Ishikawa cells were down-regulated after stimulated for 24 h and 48 h by different concentrations of 17beta-E(2). The maximal effect was observed at the concentration of 1x10(-8) mol/L. When 17beta-E(2) and ICI182,780 were given simultaneously to Ishikawa cells, this down-regulation was blocked. However, the level of ERRalpha mRNA, not protein, in HEC-IA cells was up-regulated after stimulated by different concentrations of 17beta-E(2) for 24 h. After stimulated by 17beta-E(2) for 48 h, the level of ERRalpha protein was up-regulated, which could not be blocked by ICI182,780. CONCLUSIONS: 17beta-E(2) can down-regulate the expression of ERRalpha in Ishikawa cells, which is mediated by ERalpha. 17beta-E(2) can up-regulate the expression of ERRalpha in HEC-IA cells, but this regulation cannot be blocked by ICI182,780.

Cell Line, Tumor↗
PubMed2006

[Preliminary study of membrane estrogen receptor expression in endometrial carcinoma cells].

OBJECTIVE: To analyze if there are membrane estrogen receptors (ER) in endometrial carcinoma and if there is some relationship between membrane ER and nuclear ER. METHODS: The cell membrane and total cell ERalpha and ERbeta expressions of high and moderate differentiation endometrial carcinoma cells (Ishikawa and HEC-1A cells) were analyzed. Intermittent immunofluorescence dyeing and fluorescent microscopy were carried out with the cells treated with polyformaldehyde and Triton X-100. Intermittent immunofluorescence dyeing and flow cytometry were carried out with the live cells and the cells treated with Triton X-100 respectively. RESULTS: There were fluorescences on the membrane of the Ishikawa and HEC-1A cells which were treated with polyformaldehyde. When the cells were treated with Triton X-100, the fluorescences were also seen inside the cells. The fluorescence intensity of ERalpha and ERbeta in Ishikawa cell membrane (1.09 +/- 0.21, 1.27 +/- 0.33) was stronger than the control, but there were no significant differences (P > 0.05). When treated with Triton X-100, the total cell fluorescence intensity of ERalpha and ERbeta in Ishikawa cell (4.21 +/- 0.34, 4.69 +/- 1.96) was stronger than the membrane (P < 0.05). The ERalpha and ERbeta fluorescence intensity of HEC-1A cell membrane (1.58 +/- 0.13, 1.49 +/- 0.04) were stronger than the control (P < 0.05). The fluorescence intensity of ERalpha and ERbeta of the HEC-1A cell (2.34 +/- 0.33, 2.52 +/- 0.15) was stronger than the membrane also (P < 0.05). The membrane ERalpha fluorescence intensity of Ishikawa was lower than HEC-1A (P = 0.028). But the total cell ERalpha fluorescence intensity of Ishikawa was higher than HEC-1A (P = 0.002). CONCLUSIONS: There are membrane ER on endometrial carcinoma cells Ishikawa and HEC-1A. The membrane ER must have some similarity to the nuclear receptor. There is no direct correlation between the quantity of the membrane ER and nuclear ER.

Cell Line, Tumor↗