Biomedical subjects

Y-C Wang

Publications and source records attributed to Y-C Wang.

13 recordsLinked to original sources

PubMed2025

HLA-E and NKG2A Mediate Resistance to BCG Immunotherapy in Non-Muscle-Invasive Bladder Cancer.

Bacillus Calmette-Guérin (BCG) is the first-line therapy for high-grade non-muscle-invasive bladder cancer (NMIBC), yet many patients experience recurrence due to immune evasion. We identify HLA-E and NKG2A as mediators of adaptive resistance involving chronic activation of NK and T cells in BCG-unresponsive tumors. Prolonged IFN-γ exposure enhances HLA-E and PD-L1 expression on recurrent tumors, accompanied by the accumulation of NKG2A+ NK and CD8 T cells. HLA-Ehigh tumor cells preferentially cluster near CXCL12-rich stromal regions with dense effector cell presence, underscoring a spatially segregated tumor architecture. Although cytotoxic lymphocytes retain effector potential, their activity is restrained by HLA-E/NKG2A and PD-L1/PD-1 pathways located in their immediate neighborhood within the bladder tumor microenvironment. These data reveal a spatially organized immune escape program that limits anti-tumor immunity. Our findings support dually targeting NKG2A and PD-L1 checkpoint blockade as a rational, bladder-sparing strategy for patients with BCG-unresponsive NMIBC.

BCG-unresponsive↗

PubMed2006

Performance of AEP Monitor/2-derived composite index as an indicator for depth of sedation with midazolam and alfentanil during gastrointestinal endoscopy.

BACKGROUND AND OBJECTIVE: The A-Line auditory evoked potential index (AAI) (AEP Monitor/2, Danmeter A/S, Odense, Denmark) is a newly developed composite parameter representing the degree of hypnosis. We conducted a prospective, observational study to explore the performance and validity of the AAI during conventional sedation for gastrointestinal (GI) endoscopy. METHODS: Thirty adults of either sex, age <65, scheduled for combined oesophagogastroduodenoscopy (OGD) and colonoscopy under sedation with intravenous (i.v.) midazolam and alfentanil were enrolled. The sedative end-point was set at the Observer's Assessment of Alertness/Sedation (OAA/S) score less than 4. An AEP Monitor/2 was used in all patients. AAI, sedation scores, heart rate (HR), blood pressure (BP) and SPO2 were recorded every 2 min up to the end of the procedure. Receiver operator characteristic analysis was used to test validity and to select optimal sedation. RESULTS: There was a significantly positive correlation between AAI and OAA/S scores (rho = 0.886; P < 0.001). The AAI also showed significant differences between subsequent levels of sedation scores (P < 0.001). AAI greater than 54 indicated fully awake or minimal sedation and values between 54 and 42 were suggestive of moderate sedation. Values between 42 and 34 were associated with moderate to deep sedation and readings below 34 were associated with deep sedation. The relative risk of SPO2 < 95% for OAA/S = 2 compared with 3 was 15.98 (95% confidence interval (CI): 3.94-64.81). CONCLUSIONS: AAI is an effective tool for monitoring sedation during GI endoscopy induced by i.v. midazolam and alfentanil.

Adult↗

PubMed2006

Versatile use of extra-corporeal life support to resuscitate acute respiratory distress patients.

Extra-corporeal life support (ECLS) has been applied successfully to congenital respiratory defects but less optimally to acquired pulmonary failure. We extended this support to certain extreme complexities of patients with acute respiratory distress. From January 2003 to June 2005, 16 (nine men and seven women) patients refractory to ventilator support were treated with ECLS. Their median age was 32.4 years (1.5-70). The triggering events were pulmonary haemorrhage (n = 4), pneumonia (n = 7), aspiration (n = 2) and pancreatitis (n = 3). The indications for support were hypoxaemia in 13 and hypercapnia in three patients. Ten (63%) met the criteria of fast entry. Thirteen (81%) received veno-venous (V-V) mode support and the other three received veno-arterial mode support initially, but then converted to V-V mode after sufficient oxygenation stabilised haemodynamics. Initial pump flow was maximised to improve (mean 3250 +/- 1615 ml/min) to improve the oxygenation. Four patients with active pulmonary haemorrhage were heparin free in the first 12-24 h of support without complications. Excluding one prematurely terminated patient because of brain permanent damage, the duration of support was 162 +/- 95 h (67-363). Eleven (69%) weaned successfully from ECLS and 10 (63%) discharged and regained normal pulmonary performance in a median of 26.8 months follow-up. Pulmonary support using ECLS was feasible in selected patients with acute respiratory distress. Modification of guidelines for liberal use, early deployment before secondary organ damage and prevention of complications during support were the key to final success.

Adolescent↗

PubMed2006

Laparoscopic appendectomy in the elderly.

BACKGROUND: This study aimed to compare the outcomes of laparoscopic and open appendectomy among the elderly. METHODS: Data on 53 elderly patients with a diagnosis of suspected appendicitis were prospectively collected and retrospectively reviewed. Among these patients, 24 had undergone laparoscopic appendectomy (LA) and 29 had undergone open appendectomy (OA). The indications for either method were based on the patient's choice. RESULTS: No statistically significant difference in operative time was found between the LA (70 +/- 28 min) and OA (60 +/- 22 min) groups. There was no statistically significant difference in lengths of hospital stay between the LA (4.8 +/- 3.0 days) and OA (5.0 +/- 3.1 days) groups, and there was a statistically significant difference in the postoperative analgesic doses between the LA (0.5 +/- 0.3 doses) and OA (1.7 +/- 1.5 doses) groups. No conversion of laparoscopic to open surgery was necessary, and no intraabdominal abscesses developed. CONCLUSION: According to this study, LA is as safe and effective as OA for the elderly. Furthermore, it significantly reduces postoperative wound pain.

Aged↗

PubMed2006

Urgent laparoscopic cholecystectomy in the management of acute cholecystitis: timing does not influence conversion rate.

BACKGROUND: The optimal treatment of acute cholecystitis is urgent laparoscopic cholecystectomy. Most reports suggest that a delay of 72 or 96 h from onset of symptoms leads to a higher conversion rate. This study assessed the conversion rate in relation to the timing of urgent laparoscopic cholecystectomy for acute cholecystitis. METHODS: During a 12 month period, 112 patients received laparoscopic cholecystectomy for acute cholecystitis at a tertiary care university hospital in central Taiwan. Data were collected prospectively. RESULTS: The overall conversion rate was 3.6% (4/112). Of 62 procedures performed within 72 h from onset of symptoms, 2 were converted, as compared with 2 of 50 procedures after 72 h. Of 76 procedures performed within 96 h from onset of symptoms, 3 were converted, as compared with 1 of 36 procedures after 96 h. There were no mortalities or common bile duct injuries. CONCLUSIONS: The conversion rate for urgent laparoscopic cholecystectomy among patients with acute cholecystitis can be as low as 3.6%. The timing of urgent laparoscopic cholecystectomy has no impact on the conversion rate.

Adult↗

PubMed2006

Lamivudine reverses severe acute hepatitis B and pancytopenia after renal transplantation: a case report.

Pancytopenia is rare after acute hepatitis B infection. The use of lamivudine in the treatment of acute hepatitis B-associated pancytopenia in renal transplant recipients has not been documented. Herein we reported a 21-year-old woman who was infected with acute hepatitis B 6 months after renal transplantation, a condition complicated by pancytopenia. Lamivudine reversed the acute hepatitis in 1 month and the pancytopenia after 3 months, without a change in renal function. Lamivudine was maintained for 2 years without a hepatitis flare-up after 4 years.

Adult↗

PubMed2005

Polymorphism of the adrenergic receptor alpha 2a -1291C>G genetic variation and clozapine-induced weight gain.

Weight gain, leading to further morbidity and poor treatment compliance, is a common consequence of treatment with clozapine. The substantial interindividual and interracial differences in drug-induced weight gain suggest that genetic factors may be important. Several studies showed that alpha-2, adrenoceptor may related to feeding behavior with rat or lipolytic activity of human adipocyte tissue, they are related to body weight change. In the study, we try to test the possible relation of clozapine-induced weight gain and adrenergic receptor alpha 2a -1291C>G genetic polymorphism in a long term follow up (14.0 +/- 6.2 months). Our results show the genotype GG (8.45 +/- 7.2 Kg) with higher mean body weight gain than genotype CC (2.79 +/- 6.1 Kg) (p = 0.023). The finding identify a genetic factor associated with clozapine-induced weight gain in schizophrenic patients.

Adult↗

PubMed2004

Negative association between catechol-O-methyltransferase (COMT) gene Val158Met polymorphism and persistent tardive dyskinesia in schizophrenia.

Chronic administration of typical antipsychotic agents, which mainly act on the dopamine receptors, implicates a role of dopamine system on the susceptibility of tardive dyskinesia (TD). In the present study, the association between a functional Val158Met polymorphism of Catechol-O-methyltransferase (COMT) gene and TD occurrence and TD severity was investigated in 299 Chinese schizophrenic patients with long-term antipsychotic treatment (TD: 166, non-TD: 133). After adjusting the effects of confounding factors, there was no significant association between COMT genotype and TD occurrence (p=0.367). Among TD patients, we found no significant correlation between COMT genotypes and the total scores of abnormal involuntary movement scale (AIMS) (p=0.629). We concluded that this COMT polymorphism might not play a major role in the susceptibility of TD nor on the severity of TD.

Adult↗

PubMed2004

Association analysis of a neural nitric oxide synthase gene polymorphism and antipsychotics-induced tardive dyskinesia in Chinese schizophrenic patients.

Recent findings from rodent studies with chronic administration of antipsychotic drugs have indicated the role of neural nitric oxide synthase (NOS1) on the susceptibility of tardive dyskinesia (TD). In the present study, the association between a 3'-untranslated region C267T (3'-UTR C267T) polymorphism of the NOS1 gene and TD as well as TD severity was investigated in 251 Chinese schizophrenic patients with long-term antipsychotic treatment (TD: 128, non-TD: 123). After adjusting the effects of confounding factors, there was no significant association between NOS1 3'-UTR C276T genotypes and TD occurrence (p=0.758). With in the TD group, we could not discover a significant correlation between NOS1 3'-UTR C276T genotypes and the scores of abnormal involuntary movement scale (AIMS) (p=0.219 and 0.774). We concluded that the NOS1 3'-UTR C276T polymorphism might not play a major role in the susceptibility of TD development, or on the severity of TD.

Antipsychotic Agents↗

PubMed2003

Molecular genetic analysis of the Bel phenotype.

BACKGROUND AND OBJECTIVES: In addition to the common ABO phenotypes, numerous phenotypes with a weak expression of the A or B antigens on the red blood cells have been found. This study describes the molecular genetic analysis of the Bel phenotype in Taiwanese individuals. MATERIALS AND METHODS: The exon 6-7 region of the ABO gene of an individual with the Bel phenotype was amplified by the polymerase chain reaction (PCR), cloned, and the sequences of the exons and their adjacent splice sites were analysed. A PCR-based restriction fragment length polymorphism (RFLP) analysis was designed to detect the 502C>T nucleotide change identified in the Bel allele. Six unrelated individuals with the Bel phenotype were analysed, and samples from 40 randomly selected individuals with the common B phenotype were also assessed. RESULTS: All six unrelated Taiwanese individuals with the Bel phenotype were shown to possess a B gene with the 502C>T mutation. The mutation was not detected in the general group B population. The 502C>T nucleotide change predicts an amino acid alteration of Arg168-->Trp in the encoded B transferase. CONCLUSIONS: The results suggest a new molecular basis, a 502C>T missense mutation in the B allele, for the Bel phenotype and an association of the Bel502C>T allele with the Bel phenotype in the Taiwanese population.

ABO Blood-Group System↗

PubMed2002

Association study of angiotensin I-converting enzyme polymorphism and symptomatology and antidepressant response in major depressive disorders.

Angiotensin-converting enzyme (ACE) inhibitor has mood-elevating effects, and central ACE activity is increased for suicidal patients. In addition, substance P (SP), which is degraded by ACE, has been implicated in the pathogenesis of, and evaluated in the treatment for, major depressive disorder (MDD). The present study has tested the hypothesis that an ACE-gene insertion/deletion (I/D) polymorphism is associated with onset age, clinical manifestations, suicide history, and/or antidepressant response for two groups of MDD patients. No significant differences were demonstrated for onset age (p = 0.520), suicide history (p = 0.823), or baseline, total and cluster scores for Hamilton Depression Rating Scale comparing the three ACE genotypes. Further, previous findings that this ACE polymorphism is associated with therapeutic antidepressant effects were not replicated. The results demonstrate that these ACE variants did not play a major role in the clinical manifestations or antidepressant response for our MDD patients.

Adult↗

PubMed2002

The specific anti-cancer activity of green tea (-)-epigallocatechin-3-gallate (EGCG).

The effect of the green tea polyphenol-(-)epigallocatechin-3-gallate (EGCG) was tested in cultures of normal and transformed NIH-pATM ras fibroblasts. In this system transformation can be induced at will by the addition of dexamethasone, which induces the expression of H- ras by activating the mammary tumor virus long terminal repeat (MMTV-LTR) promoter. This facilitates a reliable comparison of the susceptibility of normal and transformed cells to EGCG. It has been shown that EGCG inhibited the growth of transformed but not of the normal fibroblasts. In an attempt to elucidate the mode of the preferential inhibitory activity of EGCG, its effect on growth promoting factors has been examined. The level of ornithine decarboxylase (ODC, EC 4.1.1.17), which is a signal for cellular proliferation, was reduced by EGCG in the transformed but not in the normal cells. EGCG also showed strong inhibition of tyrosine kinase and mitogen-activated protein kinase (MAPK) activities, without affecting the kinases in the normal cells. Similarly, EGCG also preferentially decreased the levels of the oncogenes Ras and Jun in transformed cell. EGCG preferentially induced apoptosis in the transformed fibroblasts. In vitro chemosensitivity tests demonstrated that EGCG inhibited the proliferation of leukemic cells. These findings suggest that EGCG has a therapeutic potential in the combat against cancer.

3T3 Cells↗

PubMedDate not supplied

Comparison of timing of IUI in ovarian stimulated cycles.

This study was conducted to compare pregnancy rates following two different timings of intrauterine insemination (IUI) in ovarian stimulated cycles. This retrospective study included 135 couples undergoing treatment for infertility. IUI was performed at either 24 hr or 36 hr after hCG injection. Pregnancy rates did not differ between the two groups or in subgroups receiving different methods of ovarian stimulation. Pregnancy rates were similar when IUI was performed at either 24 or 36 hr after hCG injection in ovarian stimulated cycles.

Adult↗