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Min Gao

Publications and source records attributed to Min Gao.

At least 73 records · Page 4Linked to original sources

[Research status of genodermatoses in China].

Among over 300 genodernatoses, causative genes have been identified in 170 monogenetic diseases, while gene mapping has been performed in over 100 monogenetic and polygenctic skin diseases. Researches in genodermatoses has rapidly advanced in China in recent ten years. The causative genes involved in multiple familial trichoepithelioma and primary erythermalgia have been found. Two independent genome-wide scans with DNA markers have been performed to detect genetic linkage related to psoriasis and vitiligo. In this review article, we summarize these most recent findings.

Erythromelalgia↗

[Role of estrogen receptor-related receptors alpha, beta and gamma in ovarian cancer cells].

OBJECTIVE: To investigate the role of human estrogen receptor-related receptors (ERRs) in ovarian cancer. METHODS: A green fluorescent protein (GFP) reporter plasmid of ERRalpha was constructed and transfected into ovarian cancer cell lines SKOV3 and OVCAR3. RT-PCR was used to analyze the expression of ERRalpha, ERRbeta, and ERRgamma mRNA in 33 primary ovarian cancer samples and 12 normal ovarian epithelial cells. Progression-free survival time and overall survival time of patients with different expression of ERRs were analyzed by Kaplan-Meier method. RESULTS: GFP-ERRalpha fusion protein showed ERRalpha expressed in the ovarian cancer cell nucleus. Expressions of the ERRalpha and ERRgamma were increased in the ovarian cancers (58% and 48%) compared with the normal ovarian tissues (P < 0.05); ERRbeta was weakly expressed in the ovarian cancer (9%) as well as in the normal tissues (0). Expression of ERRalpha was positively correlated with the International Federation of Gynecology and Obstetrics (FIGO) stage (r = 0.639, P = 0.017) and cell grading (r = 0.520, P = 0.022). Survival analysis showed that ERRalpha positive group had a poorer overall survival (19.0 months vs. 31.5 months, P < 0.05) and ERRgamma positive group had a longer progression-free survival (18.0 months vs. 13.5 months, P < 0.05). CONCLUSIONS: ERRalpha chiefly expresses in the cell nucleus. ERRalpha and ERRgamma may play important roles in ovarian cancer.

Estrogen Receptor alpha↗

[Expression of estrogen receptor-related receptor isoforms in endometrial carcinoma tissues and its clinical significance].

OBJECTIVE: To investigate the role of estrogen receptor-related receptor (ERR), a subfamily of orphan receptors, in the tumorigenesis of endometrial carcinoma and to evaluate the clinical significance. METHODS: A total of 46 cases of endometrial carcinoma tissues and 24 cases of normal endometrium tissues were collected. Semi-quantitative reverse transcription polymerase chain reaction and immunohistochemistry were used to measure the expressions of ERR. All samples were classified into two groups according to ERalpha status. RESULTS: It was positively correlated between the ERR (alpha, beta, gamma) mRNA and protein expression (r = 0.462, P = 0.009; r = 0.689, P = 0.016 and r = 0.673, P = 0.001). The expression rate and level of ERRalpha mRNA in ERalpha-positive endometrial carcinoma (42%, 0.24 +/- 0.18) were lower than in normal endometrium (78%, 0.42 +/- 0.23; P = 0.019, P = 0.021). No significant difference was observed in the expression of ERRbeta mRNA between endometrial carcinoma (23%, 0.21 +/- 0.16) and normal endometrium (22%, 0.27 +/- 0.15; P > 0.05). In ERalpha-positive endometrial carcinoma, the expression level of ERRgamma mRNA (0.93 +/- 0.24) was higher than normal endometrium (0.72 +/- 0.21; P = 0.023). The numbers of patients of Federal International Gynecological Oncology (FIGO) stage II-IV and of deep myometrial invasion in ERRalpha mRNA positive endometrial carcinoma group were more than those in ERRalpha mRNA negative group (P = 0.017 and P = 0.033). ERRgamma mRNA positive patients had a lower occurrence of lymph metastases than negative patients (P = 0.021). CONCLUSIONS: ERR may be closely related with the tumorigenesis of endometrial carcinoma, similar to ER. ERRalpha may serve as a biomarker of poor prognosis and ERRgamma as a favorable biomarker in endometrial carcinoma.

Adult↗

[Effects of iptakalim on intracellular calcium concentrations, PKA and PKC activities in rat tail artery smooth muscle cells].

AIM: To investigate the effects of iptakalim, a new structural potassium channel opener (KCO), on intracellular calcium concentration ([Ca2+]i), protein kinase C (PKC), and cAMP-dependent kinase (PKA) activities in rat tail artery smooth muscle cells (RTA-SMC), and to analyze mechanisms involved in iptakalim reversing hypertensive vascular remodeling. METHODS: RTA-SMC was cultured and passages 3-4 were used for experiment. [Ca2+] i was measured by laser scanning confocal microscope after loaded with fluorescent indicator fluo-3-acetoxymethylester, and activities of PKA and PKC were detected by commercial assay kits (the nonradioactive PepTag system) following instructions. RESULTS: Compared with baseline, [Ca2+] i reduced significantly after iptakalim- or pinacidil-treatment at concentrations of 0.1, 1 and 10 micromol x L(-1), while diazoxide caused significant decrease at concentration of 1 and 10 micromol x L(-1). After preincubation with 1 micromol x L(-1) glibenclamide, [Ca2+] i was not significantly changed when iptakalim, pinacidil or diazoxide were added at concentration of 0.1 and 1 micromol x L(-1). Activities of PKA and PKC increased significantly by 1 micromol x L(-1) iptakalim- or pinacidil-treatment, while 1 micromol x L(-1) diazoxide induced significant change in activity of PKC but not in that of PKA. CONCLUSION: The characteristics of iptakalim on [Ca2+] i, PKA and PKC are more or less similar to those of pinacidil. Iptakalim decreased [Ca2+] i while increased PKA and PKC activities of RTA-SMCs, which may contribute to its ability to reverse antihypertensive vascular remodeling.

Animals↗

Expression of growth hormone and its receptor in chronic atrophic gastritis and its clinical significance.

AIM: To investigate the growth hormone (GH) and growth hormone receptor (GHR) expression of and its clinical significance in patients with chronic atrophic gastritis (CAG). METHODS: A total of 90 cases were enrolled in the study. Thirty were healthy controls, the other 60 patients were divided into two groups according to the endoscopical and histological diagnosis. Blood samples were drawn in the morning (menarche did not occur during the blood extraction in female patients), gastric mucosa was obtained by endoscopy. Serum GH and gastrice mucosal GHR levels were measured using radioimmunoassay (RIA) and En Vinsion technique. RESULTS: The average GH level was 1.021+/-0.132 microg/L in CAG patients, in controls it was 2.869+/-0.512 microg/L. There was a significant difference between these two groups (P<0.01). The positive rate of GHR in CAG patients was 10%, in controls the rate was 100%. There was a significant difference (P<0.01). There was no significant change of GH level (3.176+/-0.421 microg/L) in patients with gastric carcinoma compared with controls (P>0.05). CONCLUSION: The study shows that levels of GH and GHR expression are low in CAG patients. CAG pathogenesis has a correlation with mucosal nutrient deficiency, decreased levels of GH and GHR have an adverse effect on the repair and regeneration of CAG. There is no significant change of GH in gastric carcinorma patients, GH dose not play a role in the pathogenesis of gastric cancer.

Adult↗

Jun turnover is controlled through JNK-dependent phosphorylation of the E3 ligase Itch.

The turnover of Jun proteins, like that of other transcription factors, is regulated through ubiquitin-dependent proteolysis. Usually, such processes are regulated by extracellular stimuli through phosphorylation of the target protein, which allows recognition by F box-containing E3 ubiquitin ligases. In the case of c-Jun and JunB, we found that extracellular stimuli also modulate protein turnover by regulating the activity of an E3 ligase by means of its phosphorylation. Activation of the Jun amino-terminal kinase (JNK) mitogen-activated protein kinase cascade after T cell stimulation accelerated degradation of c-Jun and JunB through phosphorylation-dependent activation of the E3 ligase Itch. This pathway modulates cytokine production by effector T cells.

Animals↗

Population rates of invasive cardiac procedures in British Columbia, 1995 to 2001.

BACKGROUND: This study examined the rates of coronary angiography (CA), percutaneous coronary intervention (PCI) and coronary artery bypass graft surgery (CABG) in British Columbia (BC) between 1995 and 2001. METHODS: Data sources were as follows: CABG--BC Cardiac Registries; CA and PCI--BC Medical Services Plan; acute coronary syndromes (ACS)--Hospital Separation database; population data--BC Statistics. All rates were age and sex standardized per 100,000 BC resident adults over 20 years of age. RESULTS: The rate of diagnostic CA increased from 352 per 100,000 in 1995 to 400 per 100,000 in 2001 (P<0.01). The rate of PCI increased from 101 per 100,000 in 1995 to 154 per 100,000 in 2001 (P<0.01). Single stage 'ad hoc' PCI increased from 38% in 1995 to 68% in 2001. The rate of CABG remained stable at between 70 and 79 per 100,000. There was a downward trend in the annual hospitalized incidence of ACS (477 to 430 per 100,000, P=0.04). The incidence of ACS and the rates of CA, PCI and CABG were higher for men in all age groups. PCI was more common than CABG in all groups. CONCLUSIONS: The incidence of ACS in BC is falling. The rates of diagnostic CA and PCI are increasing. The latter finding may reflect an appropriate evidence-based response to data supporting greater application of CA following ACS after publication of several studies supporting a routine invasive approach. The PCI rate is rising compared with the CABG rate, likely reflecting changes in patient selection and improved PCI technology, as well as a limited ability of the system to provide surgical procedures.

Adult↗

A novel missense mutation of the ATP2A2 gene in a Chinese family with Darier's disease.

Darier's disease (DD) is an autosomal dominant skin disorder that is characterized by multiple keratotic papules, focal loss of adhesion and abnormal keratinization. Mutations in the ATP2A2 gene encoding sarco/endoplasmic reticulum calcium pumping ATPase type 2 have been identified as the molecular basis of DD. We report here a three-generation family with DD, and examined ATP2A2 gene mutations in this family by direct sequencing. A novel missense mutation A-->G was identified in exon 12, nucleotide 1704, which leads to the substitution of lysine by arginine at codon 514 (K514R). This study contributes to the database on ATP2A2 in DD, and further illustrates the extensive diversity of mutational events that lead to the different phenotypes of DD.

Adenine↗

Seven novel mutations of the ADAR gene in Chinese families and sporadic patients with dyschromatosis symmetrica hereditaria (DSH).

Dyschromatosis symmetrica hereditaria (DSH) is an autosomal dominant pigmentary genodermatosis characterized by hyperpigmented and hypopigmented macules of on the extremities and caused by the mutations in the ADAR gene(also called DSRAD) encoding for RNA-specific adenosine deaminase. Here we reported clinical and molecular findings of 6 Chinese multi-generation families and 2 sporadic patients with DSH. We found that the same mutation could lead to different phenotypes even in the same family and we did not establish a clear correlation between genotypes and phenotypes. Seven novel heterozygous mutations of ADAR were identified, which were c.2433_2434delAG (p.T811fs), c.2197G>T (p.E733X), c.3286C>T (p.R1096X), c.2897G>T (p.C966F), c.2797C>T (p.Q933X), c.2375delT (p.L792fs) and c.3203-2A>G respectively. Our data add new variants to the repertoire of ADAR mutations in DSH.

Adenosine Deaminase↗

Characteristics of genetic epidemiology and genetic models for vitiligo.

BACKGROUND: Vitiligo occurs with a frequency of 0.1% to 2% in various populations and is classified into several subtypes by its clinical presentation. Although genetic factors are thought to be involved in the cause of vitiligo, the genetic models for different phenotypes of vitiligo are unknown. OBJECTIVE: Our purpose was to explore potential genetic models for different phenotypes of vitiligo and analyze genetic epidemiologic characteristics of vitiligo in a Chinese population. METHODS: Information from 2247 patients and members in their families was collected using a uniform questionnaire. Patients' clinical characteristics and their family history were analyzed using software. A complex segregation analysis was conducted to propose potential genetic models for vitiligo. RESULTS: Different subtypes of vitiligo had different ages of disease onset. In relatives of patients with vitiligo, the risk of developing vitiligo increased with increasing relatedness to the patients with vitiligo. A polygenic additive model was the best model for focal vitiligo, vitiligo vulgaris, acrofacial vitiligo, and segmental vitiligo with approximately 50% heritability in each. For universal vitiligo, the best model was an environmental model. CONCLUSION: This study indicated that different phenotypes of vitiligo had different pathogeneses and genetic backgrounds. Onset of vitiligo is possibly affected by both genetic backgrounds and common environmental factors.

Adolescent↗

Traction injury during minimally invasive harvesting of the saphenous vein is associated with impaired endothelial function.

OBJECTIVE: Many methods of minimally invasive surgical harvesting of the great saphenous vein have been developed because of the morbidity related to the long skin incision after traditional (open) great saphenous vein harvesting. One such method involves the use of multiple small incisions separated by 10- to 15-cm skin bridges through which the saphenous vein is harvested. We hypothesized that this method of saphenous vein harvesting might subject the saphenous vein to considerable traction forces, resulting in impaired endothelial cell function. METHODS: Four-millimeter great saphenous vein segments were obtained from patients undergoing elective coronary artery bypass graft surgery. Group A (minimally invasive surgery) consisted of 23 rings from 20 patients (age, 65.8 +/- 11.1 years, mean +/- SD). Group B (open harvesting) consisted of 33 rings from 8 patients (age, 69.8 +/- 8.6 years). All great saphenous vein segments were undistended and were used within 24 hours of harvesting. Isometric tension experiments were performed on each ring of the great saphenous vein by using a force-displacement transducer to measure the force of contraction in grams. Measurements included developed force after exposure to high-potassium depolarizing solution and 50 micromol/L phenylephrine and decrease in force of contraction (relaxation) after exposure to 1 and 10 micromol/L acetylcholine. RESULTS: There were no differences between the minimally invasive surgery and open harvesting groups in their responses to high-potassium depolarizing solution or phenylephrine: high-potassium depolarizing solution, contractions of 4.26 +/- 0.72 g (mean +/- SEM) and 3.95 +/- 0.38 g, respectively (P =.70); phenylephrine, contractions of 3.49 +/- 0.63 g and 2.73 +/- 0.39 g, respectively (P =.41). There was no net relaxation in segments from the minimally invasive surgery group after exposure to 1.0 or 10 micromol/L acetylcholine. In contrast, rings from the open harvesting group demonstrated relaxation of -0.41 +/- 0.07 g and -0.32 +/- 0.09 g after exposure to 1.0 and 10 micromol/L acetylcholine, respectively. CONCLUSIONS: In undistended saphenous vein segments isolated from patients undergoing minimally invasive surgical and open techniques of harvesting, there was no acetylcholine-mediated endothelium-dependent relaxation in the minimally invasive surgery group. Therefore harvesting of the great saphenous vein through multiple small incisions might result in endothelial dysfunction, possibly caused by traction injury.

Aged↗

Analysis of RNA exonucleolytic activities in cellular extracts.

Three types of exonucleases contribute to the turnover of messenger RNAs in eukaryotic cells: (1) general 3'-to-5' exonucleases, (2) poly(A)-specific 3'-to-5' exonucleases, and (3) 5'-to-3' exonucleases. All three of these activities can be detected in cytoplasmic extracts from a variety of eukaryotic cells. In this chapter, we describe the preparation and use of HeLa cytoplasmic S100 extracts to study these three distinct exonuclease activities. Also included is an immunodepletion protocol that can be used to identify the enzyme responsible for a given activity. These protocols can be easily expanded to the study of trans-acting factors, cis-acting RNA sequence elements, and the interplay of components involved in RNA turnover in various mammalian cell types.

Cell Extracts↗

Revascularization use and survival outcomes after cardiac catheterization in British Columbia and Alberta.

BACKGROUND: Alberta and British Columbia have comprehensive cardiac databases that provide detailed demographic, clinical and procedural data, including coronary anatomy, on all patients undergoing cardiac catheterization. OBJECTIVES: To examine the baseline clinical characteristics of patients undergoing cardiac catheterization, describe the use of revascularization treatments (percutaneous coronary intervention [PCI] and coronary artery bypass grafting [CABG]) following catheterization, and describe survival after cardiac catheterization, stratified by treatment strategy received and proposed, using cardiac databases from Alberta and British Columbia. PATIENTS AND METHODS: All patients between 20 and 105 years of age, admitted to hospital for their first coronary angiography between April 1, 1995, and March 31, 2001, with angiographic evidence of coronary disease were included in the study. Procedure volumes, baseline characteristics and therapy received within one year of cardiac catheterization are described by province. Stepwise, multivariate logistic regression analysis was used to model determinants of the revascularization modality. Kaplan-Meier curves of one-year survival after index cardiac catheterization were estimated for the therapy received (Alberta and British Columbia) and the therapy proposed (British Columbia only). RESULTS: Patients were predominantly men (70%), commonly presented with two- or three-vessel disease, and frequently had hypertension, a history of myocardial infarction and dyslipidemia. Within one year of catheterization, 21% to 26% underwent CABG and 32% to 42% underwent PCI. Emergency or urgent status at the time of catheterization was associated with receiving PCI, while three-vessel and left main disease were associated with receiving CABG. Patients who did not undergo revascularization within one year (presumed medical therapy) had the lowest one-year survival rate (93.4%; 95% CI 92.1% to 94.7%); this group comprised patients receiving medical therapy as proposed (one-year survival rate of 95.7%, 95% CI 94.6% to 96.8%), as well as patients receiving medical therapy at variance with the proposal for revascularization (84.6%; 95% CI 80.5% to 88.9%). CONCLUSIONS: Between 53.1% and 67.5% of patients presenting for cardiac catheterization undergo revascularization within one year. Urgent status increased the probability of PCI, and anatomy (ie, three-vessel and left main) increased the probability of CABG. Patients not undergoing proposed revascularization by one year had poorer outcomes, in contrast with those proposed for medical therapy, who had excellent outcomes.

Adult↗

Outcome of mitral valve repair or replacement: a comparison by propensity score analysis.

BACKGROUND: There are no randomized trials comparing outcomes after mitral valve (MV) repair and replacement. Propensity scoring is a powerful tool that has the potential to reduce selection bias in nonrandomized studies. METHODS: From the BC Cardiac Registries, 2,060 patients presented for MV surgery, with or without CABG between 1991 and 2000. We then identified 322 MV repairs who were then matched by propensity score to an equal number of MV replacement patients. We compared survival and freedom from re-operation outcomes using Cox proportional hazards model analysis. Multivariable analysis was then used to compare outcomes in 358 MV repair patients with 352 MV replacement patients who had undergone chordal sparing surgery. RESULTS: The comparison groups generated using propensity scores were well balanced with respect to all collected baseline risk factors. Median follow-up time was 3.4 years. Patients undergoing MV repair had significantly improved survival (RR 0.46; 95% CI, 0.28 to 0.75) but a trend toward more re-operations (RR 2.11; 95% CI, 1.00 to 4.47) compared with patients undergoing replacement. Mitral valve repair patients still had better survival (RR 0.52; 95% CI, 0.32 to 0.85) compared with MV replacement patients who had undergone chordal sparing surgery. CONCLUSIONS: We used propensity score methods to reduce selection bias in a population-based cohort of patients undergoing MV repair/replacement. Repair was associated with better survival, but a trend to increased re-operation.

Disease-Free Survival↗

A role for MEK kinase 1 in TGF-beta/activin-induced epithelium movement and embryonic eyelid closure.

MEKK1-deficient mice show an eye open at birth phenotype caused by impairment in embryonic eyelid closure. MEK kinase 1 (MEKK1) is highly expressed in the growing tip of the eyelid epithelium, which displays loose cell-cell contacts and prominent F-actin fibers in wild-type mice, but compact cell contacts, lack of polymerized actin and a concomitant impairment in c-Jun N-terminal phosphorylation in MEKK1-deficient mice. In cultured keratinocytes, MEKK1 is essential for JNK activation by TGF-beta and activin, but not by TGF-alpha. MEKK1-driven JNK activation is required for actin stress fiber formation, c-Jun phosphorylation and cell migration. However, MEKK1 ablation does not impair other TGF-beta/activin functions, such as nuclear translocation of Smad4. These results establish a specific role for the MEKK1-JNK cascade in transmission of TGF-beta and activin signals that control epithelial cell movement, providing the mechanistic basis for the regulation of eyelid closure by MEKK1. This study also suggests that the signaling mechanisms that control eyelid closure in mammals and dorsal closure in Drosophila are evolutionarily conserved.

Actins↗