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1.
J Biol Chem ; 299(2): 102851, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36587767

RESUMEN

Misfolded proteins are recognized and degraded through protein quality control (PQC) pathways, which are essential for maintaining proteostasis and normal cellular functions. Defects in PQC can result in disease, including cancer, cardiovascular disease, and neurodegeneration. The small ubiquitin-related modifiers (SUMOs) were previously implicated in the degradation of nuclear misfolded proteins, but their functions in cytoplasmic PQC are unclear. Here, in a systematic screen of SUMO protein mutations in the budding yeast Saccharomyces cerevisiae, we identified a mutant allele (Smt3-K38A/K40A) that sensitizes cells to proteotoxic stress induced by amino acid analogs. Smt3-K38A/K40A mutant strains also exhibited a defect in the turnover of a soluble PQC model substrate containing the CL1 degron (NES-GFP-Ura3-CL1) localized in the cytoplasm, but not the nucleus. Using human U2OS SUMO1- and SUMO2-KO cell lines, we observed a similar SUMO-dependent pathway for degradation of the mammalian degron-containing PQC reporter protein, GFP-CL1, also only in the cytoplasm but not the nucleus. Moreover, we found that turnover of GFP-CL1 in the cytoplasm was uniquely dependent on SUMO1 but not the SUMO2 paralogue. Additionally, we showed that turnover of GFP-CL1 in the cytoplasm is dependent on the AAA-ATPase, Cdc48/p97. Cellular fractionation studies and analysis of a SUMO1-GFP-CL1 fusion protein revealed that SUMO1 promotes cytoplasmic misfolded protein degradation by maintaining substrate solubility. Collectively, our findings reveal a conserved and previously unrecognized role for SUMO1 in regulating cytoplasmic PQC and provide valuable insights into the roles of sumoylation in PQC-associated diseases.


Asunto(s)
Proteolisis , Proteína SUMO-1 , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Animales , Humanos , Citoplasma/metabolismo , Citosol/metabolismo , Proteínas Nucleares/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteína SUMO-1/genética , Proteína SUMO-1/metabolismo
2.
Front Genet ; 12: 753535, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34868226

RESUMEN

Sumoylation is an important enhancer of responses to DNA replication stress and the SUMO-targeted ubiquitin E3 ligase RNF4 regulates these responses by ubiquitylation of sumoylated DNA damage response factors. The specific targets and functional consequences of RNF4 regulation in response to replication stress, however, have not been fully characterized. Here we demonstrated that RNF4 is required for the restart of DNA replication following prolonged hydroxyurea (HU)-induced replication stress. Contrary to its role in repair of γ-irradiation-induced DNA double-strand breaks (DSBs), our analysis revealed that RNF4 does not significantly impact recognition or repair of replication stress-associated DSBs. Rather, using DNA fiber assays, we found that the firing of new DNA replication origins, which is required for replication restart following prolonged stress, was inhibited in cells depleted of RNF4. We also provided evidence that RNF4 recognizes and ubiquitylates sumoylated Bloom syndrome DNA helicase BLM and thereby promotes its proteosome-mediated turnover at damaged DNA replication forks. Consistent with it being a functionally important RNF4 substrate, co-depletion of BLM rescued defects in the firing of new replication origins observed in cells depleted of RNF4 alone. We concluded that RNF4 acts to remove sumoylated BLM from collapsed DNA replication forks, which is required to facilitate normal resumption of DNA synthesis after prolonged replication fork stalling and collapse.

3.
Mol Biol Cell ; 32(19): 1849-1866, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34232706

RESUMEN

The small ubiquitin-related modifiers (SUMOs) regulate nearly every aspect of cellular function, from gene expression in the nucleus to ion transport at the plasma membrane. In humans, the SUMO pathway has five SUMO paralogues with sequence homologies that range from 45% to 97%. SUMO1 and SUMO2 are the most distantly related paralogues and also the best studied. To what extent SUMO1, SUMO2, and the other paralogues impart unique and nonredundant effects on cellular functions, however, has not been systematically examined and is therefore not fully understood. For instance, knockout studies in mice have revealed conflicting requirements for the paralogues during development and studies in cell culture have relied largely on transient paralogue overexpression or knockdown. To address the existing gap in understanding, we first analyzed SUMO paralogue gene expression levels in normal human tissues and found unique patterns of SUMO1-3 expression across 30 tissue types, suggesting paralogue-specific functions in adult human tissues. To systematically identify and characterize unique and nonredundant functions of the SUMO paralogues in human cells, we next used CRISPR-Cas9 to knock out SUMO1 and SUMO2 expression in osteosarcoma (U2OS) cells. Analysis of these knockout cell lines revealed essential functions for SUMO1 and SUMO2 in regulating cellular morphology, promyelocytic leukemia (PML) nuclear body structure, responses to proteotoxic and genotoxic stress, and control of gene expression. Collectively, our findings reveal nonredundant regulatory roles for SUMO1 and SUMO2 in controlling essential cellular processes and provide a basis for more precise SUMO-targeting therapies.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica , Proteína SUMO-1/genética , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/genética , Ubiquitinas/genética , Sistemas CRISPR-Cas/genética , Línea Celular Tumoral , Supervivencia Celular/genética , Técnicas de Inactivación de Genes , Ontología de Genes , Humanos , Immunoblotting/métodos , Microscopía Fluorescente/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Proteína SUMO-1/metabolismo , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/metabolismo , Ubiquitinas/metabolismo
4.
Biochim Biophys Acta Mol Basis Dis ; 1867(6): 166104, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33617988

RESUMEN

Depolarized/damaged mitochondria aggregate at the perinuclear region prior to mitophagy in cells treated with mitochondrial stressors. However, the cellular mechanism(s) by which damaged mitochondria are transported and remain aggregated at the perinuclear region is unknown. Here, we demonstrate that mitofusins (Mfn1/2) are post-translationally modified by SUMO2 (Small Ubiquitin-related Modifier 2) in Human embryonic kidney 293 (Hek293) cells treated with protonophore CCCP and proteasome inhibitor MG132, both known mitochondrial stressors. SUMOylation of Mfn1/2 is not for their proteasomal degradation but facilitate mitochondrial congression at the perinuclear region in CCCP- and MG132-treated cells. Additionally, congressed mitochondria (mito-aggresomes) colocalize with LC3, ubiquitin, and SUMO2 in CCCP-treated cells. Knowing that SUMO functions as a "molecular glue" to facilitate protein-protein interactions, we propose that SUMOylation of Mfn1/2 may congress, glues, and confines damaged mitochondria to the perinuclear region thereby, protectively quarantining them from the heathy mitochondrial network until their removal via mitophagy in cells.


Asunto(s)
Carbonil Cianuro m-Clorofenil Hidrazona/farmacología , Núcleo Celular/metabolismo , GTP Fosfohidrolasas/metabolismo , Mitocondrias/patología , Proteínas de Transporte de Membrana Mitocondrial/metabolismo , Proteínas Mitocondriales/metabolismo , Mitofagia , Sumoilación , GTP Fosfohidrolasas/genética , Células HEK293 , Humanos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Proteínas de Transporte de Membrana Mitocondrial/genética , Proteínas Mitocondriales/genética , Ionóforos de Protónes/farmacología , Estrés Fisiológico
5.
Front Immunol ; 11: 623, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32425926

RESUMEN

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer with a poor prognosis and limited therapeutic options. Alpha-fetoprotein (AFP), an established clinical biomarker of HCC, has been employed as an attractive target for T cell-based immunotherapy against this disease given its high expression in the tumor and restricted expression in normal tissues. We have identified a number of T cell receptors (TCRs) recognizing the HLA-A*02:01 restricted AFP158-166 peptide FMNKFIYEI, providing a TCR candidate pool for identifying TCRs with optimal clinical benefit. To select the ideal AFP TCR for clinical use, we evaluated the efficacy and safety profile of 7 TCRs by testing their potency toward AFP-expressing HCC cells and their specificity based upon reactivity to normal and transformed cells covering a wide variety of primary cell types and HLA serotypes. Furthermore, we assessed their cross-reactivity to potential protein candidates in the human genome by an extensive alanine scan (X-scan). We first selected three TCR candidates based on the in vitro anti-tumor activity. Next we eliminated two potential cross-reactive TCRs based on their reactivity against normal and transformed cells covering a variety of primary cell types and HLA serotypes, respectively. We then excluded the potential cross-reactivity of the selected TCR with a protein candidate identified by X-scan. At present we have selected an AFP TCR with the optimal affinity, function, and safety profile, bearing properties that are expected to allow AFP TCR redirected T cells to specifically differentiate between AFP levels on tumor and normal tissues. An early phase clinical trial using T cells transduced with this TCR to treat HCC patients (NCT03971747) has been initiated.


Asunto(s)
Carcinoma Hepatocelular/terapia , Inmunoterapia/métodos , Neoplasias Hepáticas/terapia , Péptidos/inmunología , Linfocitos T/metabolismo , alfa-Fetoproteínas/inmunología , Carcinoma Hepatocelular/inmunología , Reacciones Cruzadas , Antígeno HLA-A2/metabolismo , Células Hep G2 , Humanos , Isoantígenos , Neoplasias Hepáticas/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Medición de Riesgo , Linfocitos T/inmunología
6.
BMC Med Ethics ; 18(1): 62, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-29141641

RESUMEN

BACKGROUND: The relationships between age and the life-supporting treatments use, and between gender and the life-supporting treatments use are still controversial. Using extracorporeal membrane oxygenation as an example of life-supporting treatments, the objectives of this study were: (1) to examine the relationship between age and the extracorporeal membrane oxygenation use; (2) to examine the relationship between age and the extracorporeal membrane oxygenation use; and (3) to deliberate the ethical and societal implications of age and gender disparities in the initiation of extracorporeal membrane oxygenation. METHODS: This is a population-based, retrospective cohort study. Taiwan's extracorporeal membrane oxygenation cases from 2000 to 2010 were collected. The annual incidence rate of extracorporeal membrane oxygenation use adjusting for both age and gender distribution for each year from 2000 to 2010 was derived using the population of 2000 as the reference population. The trend of extracorporeal membrane oxygenation use was examined using time-series linear regression analysis. We conducted joinpoint regression for estimating the trend change of extracorporeal membrane oxygenation use. RESULTS: The trends of extracorporeal membrane oxygenation use both for different gender groups, and for different age groups have been significantly increasing over time. Men were more likely to be supported by extracorporeal membrane oxygenation than women. Women's perspectives toward life and death, and women's perception of well-being may be associated with the phenomenon. In addition, the patients at the age of 65 or older were more likely to be supported by extracorporeal membrane oxygenation than those younger than 65. Family autonomy/family-determination, and the Confucian tradition of filial piety and respecting elders may account for this phenomenon. CONCLUSIONS: This study showed gender and age disparities in the initiation of extracorporeal membrane oxygenation use in Taiwan, which may be accounted for by the cultural and societal values in Taiwan. For a healthcare professional who deals with patients'/family members' medical decision-making to initiate life-supporting treatments, he/she should be sensitive not only to the legality, but also the societal and ethical issues involved.


Asunto(s)
Reanimación Cardiopulmonar , Oxigenación por Membrana Extracorpórea , Disparidades en Atención de Salud , Cuidados para Prolongación de la Vida , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Actitud , Reanimación Cardiopulmonar/ética , Niño , Preescolar , Cultura , Ética Médica , Oxigenación por Membrana Extracorpórea/ética , Femenino , Disparidades en Atención de Salud/ética , Humanos , Lactante , Recién Nacido , Cuidados para Prolongación de la Vida/ética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores Sexuales , Taiwán , Adulto Joven
7.
Int J Chron Obstruct Pulmon Dis ; 12: 2477-2485, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28860742

RESUMEN

BACKGROUND: It remains unclear whether severe exacerbation and pneumonia of COPD differs between patients treated with budesonide/formoterol and those treated with fluticasone/salmeterol. Therefore, we conducted a comparative study of those who used budesonide/formoterol and those treated with fluticasone/salmeterol for COPD. METHODS: Subjects in this population-based cohort study comprised patients with COPD who were treated with a fixed combination of budesonide/formoterol or fluticasone/salmeterol. All patients were recruited from the Taiwan National Health Insurance database. The outcomes including severe exacerbations, pneumonia, and pneumonia requiring mechanical ventilation (MV) were measured. RESULTS: During the study period, 11,519 COPD patients receiving fluticasone/salmeterol and 7,437 patients receiving budesonide/formoterol were enrolled in the study. Pairwise matching (1:1) of fluticasone/salmeterol and budesonide/formoterol populations resulted in to two similar subgroups comprising each 7,295 patients. Patients receiving fluticasone/salmeterol had higher annual rate and higher risk of severe exacerbation than patients receiving budesonide/formoterol (1.2219/year vs 1.1237/year, adjusted rate ratio, 1.08; 95% CI, 1.07-1.10). In addition, patients receiving fluticasone/salmeterol had higher incidence rate and higher risk of pneumonia than patients receiving budesonide/formoterol (12.11 per 100 person-years vs 10.65 per 100 person-years, adjusted hazard ratio [aHR], 1.13; 95% CI, 1.08-1.20). Finally, patients receiving fluticasone/salmeterol had higher incidence rate and higher risk of pneumonia requiring MV than patients receiving budesonide/formoterol (3.94 per 100 person-years vs 3.47 per 100 person-years, aHR, 1.14; 95% CI, 1.05-1.24). A similar trend was seen before and after propensity score matching analysis, intention-to-treat, and as-treated analysis with and without competing risk. CONCLUSIONS: Based on this retrospective observational study, long-term treatment with fixed combination budesonide/formoterol was associated with fewer severe exacerbations, pneumonia, and pneumonia requiring MV than fluticasone/salmeterol in COPD patients.


Asunto(s)
Agonistas de Receptores Adrenérgicos beta 2/administración & dosificación , Broncodilatadores/administración & dosificación , Combinación Budesonida y Fumarato de Formoterol/administración & dosificación , Combinación Fluticasona-Salmeterol/administración & dosificación , Glucocorticoides/administración & dosificación , Pulmón/efectos de los fármacos , Neumonía/etiología , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Administración por Inhalación , Agonistas de Receptores Adrenérgicos beta 2/efectos adversos , Anciano , Broncodilatadores/efectos adversos , Combinación Budesonida y Fumarato de Formoterol/efectos adversos , Bases de Datos Factuales , Progresión de la Enfermedad , Femenino , Combinación Fluticasona-Salmeterol/efectos adversos , Glucocorticoides/efectos adversos , Humanos , Modelos Logísticos , Pulmón/fisiopatología , Masculino , Persona de Mediana Edad , Neumonía/diagnóstico , Neumonía/fisiopatología , Neumonía/terapia , Puntaje de Propensión , Modelos de Riesgos Proporcionales , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Respiración Artificial , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Taiwán , Factores de Tiempo , Resultado del Tratamiento
8.
Support Care Cancer ; 25(3): 757-768, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27785583

RESUMEN

PURPOSE: This study investigated the short- and long-term use of medication for psychological distress after the diagnosis of cancer. METHODS: Longitudinal data from the Taiwan National Health Insurance database were used to follow 35,137 cancer patients for 2.5 years after being diagnosed in 2006 and 2007. RESULTS: Among those patients who survived for at least 180 days, 20.9 % had used psychotropic medications; sedatives were the most frequently prescribed (14.3 %), followed by antidepressants (5.5 %), anxiolytics (3.6 %), and antipsychotics (2.7 %). Lung cancer, prostate cancer, and oral cancer showed a significant association with the regular use of medication in the first 180 days. Among patients who survived for at least 2.5 years, 4.8 % still used psychotropic medication on a regular basis. Lung cancer and prostate cancer were associated with such prolonged use. CONCLUSIONS: This longitudinal study found that the type of cancer was significantly associated with the use of psychotropic drugs after the diagnosis was made. It provided information about the trajectory of that use and found that a small number of patients were still using those medications after 2.5 years.


Asunto(s)
Neoplasias/psicología , Psicotrópicos/administración & dosificación , Estrés Psicológico/tratamiento farmacológico , Anciano , Esquema de Medicación , Femenino , Humanos , Hipnóticos y Sedantes/administración & dosificación , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Programas Nacionales de Salud , Estudios Retrospectivos , Estrés Psicológico/etiología , Estrés Psicológico/psicología , Taiwán
9.
Int J Chron Obstruct Pulmon Dis ; 11: 2775-2783, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27877031

RESUMEN

To investigate the association between inhaled corticosteroid (ICS) exposure patterns and the risk of pneumonia in chronic obstructive pulmonary disease (COPD) patients, we performed a nested case-control study. Between 1998 and 2010, 51,739 patients, including 19,838 cases of pneumonia, were matched to 74,849 control subjects selected from a cohort of COPD patients using ICSs via risk-set sampling of the database constructed by the National Health Research Institutes of Taiwan. After adjusting for covariates, the current use of ICSs was associated with a 25% increase in the risk of pneumonia (odds ratio [OR] =1.25, 95% confidence interval [CI] =1.20-1.30), and there was an increase in the OR with increase in the average daily dosage. Additionally, users of fluticasone/salmeterol, fluticasone, and either fluticasone/salmeterol or fluticasone were more likely to be at a higher risk of pneumonia (OR =1.35, 95% CI =1.28-1.41; OR =1.22, 95% CI =1.10-1.35; and OR =1.33, 95% CI =1.27-1.39, respectively). In contrast, there were no statistically significant associations between the risk of pneumonia and the use of budesonide/formoterol, budesonide, or either budesonide/formoterol or budesonide. In conclusion, ICSs are significantly associated with an increased risk of pneumonia in COPD patients. The effect is prominent for fluticasone-containing ICSs but not for budesonide-containing ICSs.


Asunto(s)
Corticoesteroides/efectos adversos , Broncodilatadores/efectos adversos , Combinación Fluticasona-Salmeterol/efectos adversos , Pulmón/efectos de los fármacos , Neumonía/inducido químicamente , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Calidad de Vida , Administración por Inhalación , Corticoesteroides/administración & dosificación , Anciano , Anciano de 80 o más Años , Broncodilatadores/administración & dosificación , Combinación Budesonida y Fumarato de Formoterol/efectos adversos , Estudios de Casos y Controles , Estudios Transversales , Bases de Datos Factuales , Femenino , Humanos , Modelos Logísticos , Pulmón/fisiopatología , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Neumonía/diagnóstico , Neumonía/fisiopatología , Neumonía/psicología , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/psicología , Medición de Riesgo , Factores de Riesgo , Taiwán , Factores de Tiempo , Resultado del Tratamiento
10.
PLoS One ; 11(3): e0150435, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26986737

RESUMEN

D-amino acid oxidase (DAO) has been reported to be associated with schizophrenia. This study aimed to search for genetic variants associated with this gene. The genomic regions of all exons, highly conserved regions of introns, and promoters of this gene were sequenced. Potentially meaningful single-nucleotide polymorphisms (SNPs) obtained from direct sequencing were selected for genotyping in 600 controls and 912 patients with schizophrenia and in a replicated sample consisting of 388 patients with schizophrenia. Genetic associations were examined using single-locus and haplotype association analyses. In single-locus analyses, the frequency of the C allele of a novel SNP rs55944529 located at intron 8 was found to be significantly higher in the original large patient sample (p = 0.016). This allele was associated with a higher level of DAO mRNA expression in the Epstein-Barr virus-transformed lymphocytes. The haplotype distribution of a haplotype block composed of rs11114083-rs2070586-rs2070587-rs55944529 across intron 1 and intron 8 was significantly different between the patients and controls and the haplotype frequencies of AAGC were significantly higher in patients, in both the original (corrected p < 0.0001) and replicated samples (corrected p = 0.0003). The CGTC haplotype was specifically associated with the subgroup with deficits in sustained attention and executive function and the AAGC haplotype was associated with the subgroup without such deficits. The DAO gene was a susceptibility gene for schizophrenia and the genomic region between intron 1 and intron 8 may harbor functional genetic variants, which may influence the mRNA expression of DAO and neurocognitive functions in schizophrenia.


Asunto(s)
D-Aminoácido Oxidasa/genética , Polimorfismo de Nucleótido Simple , Esquizofrenia/genética , Adolescente , Adulto , Femenino , Predisposición Genética a la Enfermedad , Haplotipos , Humanos , Masculino , Adulto Joven
11.
J Biol Chem ; 291(17): 9014-24, 2016 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-26917720

RESUMEN

Thymine-DNA glycosylase (TDG) plays critical roles in DNA base excision repair and DNA demethylation. It has been proposed, based on structural studies and in vitro biochemistry, that sumoylation is required for efficient TDG enzymatic turnover following base excision. However, whether sumoylation is required for TDG activity in vivo has not previously been tested. We have developed an in vivo assay for TDG activity that takes advantage of its recently discovered role in DNA demethylation and selective recognition and repair of 5-carboxylcytosine. Using this assay, we investigated the role of sumoylation in regulating TDG activity through the use of TDG mutants defective for sumoylation and Small Ubiquitin-like Modifier (SUMO) binding and by altering TDG sumoylation through SUMO and SUMO protease overexpression experiments. Our findings indicate that sumoylation and SUMO binding are not essential for TDG-mediated excision and repair of 5-carboxylcytosine bases. Moreover, in vitro assays revealed that apurinic/apyrimidinic nuclease 1 provides nearly maximum stimulation of TDG processing of G·caC substrates. Thus, under our assay conditions, apurinic/apyrimidinic nuclease 1-mediated stimulation or other mechanisms sufficiently alleviate TDG product inhibition and promote its enzymatic turnover in vivo.


Asunto(s)
Citosina/análogos & derivados , Metilación de ADN/fisiología , Mutación , Proteína SUMO-1/metabolismo , Sumoilación/fisiología , Timina ADN Glicosilasa/metabolismo , Citosina/metabolismo , Células HEK293 , Humanos , Proteína SUMO-1/genética , Timina ADN Glicosilasa/genética
12.
Biol Psychiatry ; 70(1): 51-8, 2011 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-21531385

RESUMEN

BACKGROUND: A genome scan of Taiwanese schizophrenia families suggested linkage to chromosome 10q22.3. We aimed to find the candidate genes in this region. METHODS: A total of 476 schizophrenia families were included. Hierarchical clustering method was used for clustering families to homogeneous subgroups according to their performances of sustained attention and executive function. Association analysis was performed using family-based association testing and TRANSMIT. Candidate associated regions were identified using the longest significance run method. The relative messenger RNA expression level was determined using real-time reverse transcriptase polymerase chain reaction. RESULTS: First, we genotyped 18 microsatellite markers between D10S1432 and D10S1239. The maximum nonparametric linkage score was 2.79 on D10S195. Through family clustering, we found the maximum nonparametric linkage score was 3.70 on D10S195 in the family cluster with deficits in attention and executive function. Second, we genotyped 79 single nucleotide polymorphisms between D10S1432 and D10S580 in 90 attention deficit and execution deficit families. Association analysis indicated significant transmission distortion for nine single nucleotide polymorphisms. Using the longest significance run method, we identified a 427-kilobase region as a significant candidate region, which encompasses nine genes. Third, we studied messenger RNA expression of these nine genes in Epstein-Barr virus-transformed lymphoblastic cells. In schizophrenic patients, there was significantly lower expression of ANXA7, PPP3CB, and DNAJC9 and significantly higher expression of ZMYND17. CONCLUSIONS: ANXA7, PPP3CB, DNAJC9, and ZMYND17 genes are potential candidate genes for schizophrenia, especially in patients with deficits in sustained attention and executive function. The responsible functional variants remained to be clarified.


Asunto(s)
Anexina A7/genética , Trastorno por Déficit de Atención con Hiperactividad/genética , Calcineurina/genética , Proteínas Portadoras/genética , Función Ejecutiva/fisiología , Proteínas del Choque Térmico HSP40/genética , Esquizofrenia/genética , Psicología del Esquizofrénico , Adulto , Anexina A7/biosíntesis , Trastorno por Déficit de Atención con Hiperactividad/complicaciones , Calcineurina/biosíntesis , Proteínas Portadoras/biosíntesis , Células Cultivadas , Cromosomas Humanos Par 10/genética , Femenino , Expresión Génica , Estudios de Asociación Genética/métodos , Ligamiento Genético , Genotipo , Proteínas del Choque Térmico HSP40/biosíntesis , Humanos , Masculino , Pruebas Neuropsicológicas , Polimorfismo de Nucleótido Simple , Esquizofrenia/complicaciones , Esquizofrenia/metabolismo
13.
Neurosci Lett ; 468(3): 330-3, 2010 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-19914334

RESUMEN

The pathophysiological process of schizophrenia is still unclear. The levels of interleukine-6 (IL-6) and its receptor, soluble IL-6R, have been reported to be elevated in the plasma and cerebrospinal fluid of schizophrenic patients. In this study, we tested the association of genetic variants of IL-6 and IL-6R with schizophrenia. Genotyping of three single nucleotide polymorphisms (SNP) for each IL-6 (IL-6-1, IL-6-2, and IL-6-3) and IL-6R (rs4845617=IL-6R1, rs4553185=IL-6R2, and rs4379670=IL-6R3) gene was performed in 100 patients with schizophrenia and 113 normal controls. The polymorphisms of IL-6R2 were genotyped using Tetra-primer ARMS PCR. IL-6R3 polymorphisms were genotyped using restriction fragment length polymorphism (RFLP) with Apo I enzyme as the restriction enzyme. All other polymorphisms were genotyped using the direct sequencing method. We found a di-nucleotide haplotype block and a tri-nucleotide haplotype block in the genes of IL-6 and IL-6R, respectively. All six SNPs and their haplotypes failed to show a significant association with schizophrenia. The IL-6-2 SNP showed a nominally significant association with the positive symptoms of schizophrenia (p=0.0472). We conclude that the genetic variants of IL-6 and IL-6R are not associated with schizophrenia. In order to verify this result, further study using a larger sample size and exploring the association between the genotype of IL-6-2 and plasma level of IL-6 is recommended.


Asunto(s)
Interleucina-6/genética , Receptores de Interleucina-6/genética , Esquizofrenia/genética , Adulto , Pueblo Asiatico , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Masculino , Polimorfismo de Nucleótido Simple , Esquizofrenia/fisiopatología , Taiwán
14.
Biol Psychiatry ; 64(9): 789-96, 2008 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-18571626

RESUMEN

BACKGROUND: In a previous linkage study of schizophrenia that included Taiwanese samples, the marker D22S278 (22q12.3) was significantly linked to schizophrenia (p = .001). METHODS: We conducted fine mapping of the implicated genomic region, with 47 validated single nucleotide polymorphism (SNP) markers around 1 Mb of D22S278, in a Taiwanese sample of 218 pedigrees with at least 2 siblings affected with schizophrenia. We examined the association of these SNPs and their haplotypes with schizophrenia and with subgroups defined by the presence and absence of deficits in sustained attention as assessed by undegraded and degraded continuous performance tests (CPTs). We also examined subgroups defined by deficits in categories achieved in the Wisconsin Card Sort Test (WCST). RESULTS: Three of five candidate vulnerability genes (RASD2, APOL5, MYH9, EIF3S7, and CACNG2), which had marginally significant associations with schizophrenia, had significant associations with schizophrenic patients who did not have deficits in sustained attention on the undegraded CPT (RASD2 gene SNP rs736212; p = .0008 with single locus analysis) and the degraded CPT (MYH9 gene haplotype 1-1-1-1 of SNP rs3752463 - rs1557540 - rs713839 - rs739097; p = .0059 with haplotype analysis). We also found a significant association for patients who showed no deficits in executive function as measured by categories achieved in the WCST (CACNG2 gene haplotype 2-1-1-1 of SNP rs2267360 - rs140526 - rs1883987 - rs916269; p = .0163 with haplotype analysis). CONCLUSIONS: The genes RASD2, MYH9, and CACNG2 might be vulnerability genes for neuropsychologically defined subgroups of schizophrenic patients.


Asunto(s)
Canales de Calcio/genética , Cromosomas Humanos Par 22 , Proteínas de Unión al GTP/genética , Predisposición Genética a la Enfermedad , Proteínas Motoras Moleculares/genética , Cadenas Pesadas de Miosina/genética , Esquizofrenia/genética , Esquizofrenia/fisiopatología , Adulto , Anciano , Atención/fisiología , Salud de la Familia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Polimorfismo de Nucleótido Simple/genética , Solución de Problemas/fisiología , Esquizofrenia/clasificación
15.
Behav Brain Funct ; 4: 21, 2008 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-18501009

RESUMEN

BACKGROUND: Monoamine oxidase A (MAOA) is a mitochondrial enzyme involved in degrading several different biological amines, including serotonin. Although several pieces of evidence suggested that MAOA is important in the etiology of bipolar affective disorder (BPD), associations for markers of the MAOA gene with BPD were not conclusive and the association has not been investigated in Taiwanese population. This study was designed to illustrate the role of MAOA in the etiology of BPD in Han Chinese. METHODS: Two markers, a dinucleotide polymorphism in exon 2 and a functional uVNTR on the promoter of the MAOA gene, were used to study the genetic association in 108 unrelated patients with BPD and 103 healthy controls. Allelic distributions of two polymorphisms were analyzed and, caused the MAOA located at X chromosome, haplotype association was performed using haplotype unambiguously assigned in male participants. RESULTS: While no difference in allelic distributions of two MAOA polymorphisms was found, the risk haplotype 114S was associated with BPD in male patients (P = 0.03). The significance, however, was not found in female patients with 114S haplotype. CONCLUSION: Results from this study suggest that MAOA may have a gender-specific and small effect on the etiology of BPD in Taiwan. Due to the limited sample size, results from this study need to be confirmed in replicates.

16.
BMC Health Serv Res ; 8: 67, 2008 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-18373869

RESUMEN

BACKGROUND: Taiwan's National Health Insurance (NHI), implemented in 1995, substantially increased the number of health care facilities that can deliver free prenatal care. Because of the increase in such facilities, it is usually assumed that women would have more choices regarding prenatal care facilities and thus experience reduction in travel cost. Nevertheless, there has been no research exploring these issues in the literature. This study compares how Taiwan's NHI program may have influenced choice of prenatal care facility and perception regarding convenience in transportation for obtaining such care for women in rural and non-rural areas in Taiwan. METHODS: Based on data collected by a national survey conducted by Taiwan's National Health Research Institutes (NHRI) in 2000, we tried to compare how women chose prenatal care facility before and after Taiwan's National Health Insurance program was implemented. Basing our analysis on how women answered questionnaire items regarding "the type of major health care facility used and convenience of transportation to and from prenatal care facility," we investigated whether there were disparities in how women in rural and non-rural areas chose prenatal care facilities and felt about the transportation, and whether the NHI had different influences for the two groups of women. RESULTS: After NHI, women in rural areas were more likely than before to choose large hospitals for prenatal care services. For women in rural areas, the relative probability of choosing large hospitals to choosing non-hospital settings in 1998-1999 was about 6.54 times of that in 1990-1992. In contrast, no such change was found in women in non-rural areas. For a woman in a non-rural area, she was significantly more likely to perceive the transportation to and from prenatal care facilities to be very convenient between 1998 and 1999 than in the period between 1990 and 1992. No such improvement was found for women in rural areas. CONCLUSION: We concluded that women in rural areas were more likely to seek prenatal care in large hospitals, but were not more likely to perceive very convenient transportation to and from prenatal care facilities in the late 1990s than in the early 1990s. In contrast, women in non-rural areas did not have a stronger tendency to seek prenatal care in large hospitals in the late 1990s than in earlier periods. In addition, they did perceive an improvement in transportation for acquiring prenatal care in the late 1990s. More efforts should be made to reduce these disparities.


Asunto(s)
Conducta de Elección , Instituciones de Salud/estadística & datos numéricos , Programas Nacionales de Salud , Atención Prenatal/estadística & datos numéricos , Adolescente , Adulto , Femenino , Instituciones de Salud/economía , Accesibilidad a los Servicios de Salud/economía , Investigación sobre Servicios de Salud , Maternidades/estadística & datos numéricos , Humanos , Persona de Mediana Edad , Atención Prenatal/economía , Calidad de la Atención de Salud/normas , Población Rural , Factores Socioeconómicos , Encuestas y Cuestionarios , Taiwán , Viaje/economía , Atención no Remunerada/estadística & datos numéricos , Población Urbana
17.
BMC Public Health ; 8: 118, 2008 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-18405385

RESUMEN

BACKGROUND: Controlling the growth of pharmaceutical expenditures is a major global challenge. Promotion of generic drug prescriptions or use is gaining increased support. There are substantial contextual differences in international experiences of implementing pharmaceutical policies related to generic drugs. Reporting these experiences from varied perspectives can inform future policy making. This study describes an experience of Taiwan, where patients with chronic (long-term) conditions are usually managed in hospitals and drugs are provided in this setting with costs reimbursed through the National Health Insurance (NHI). It investigates the effects of Taiwan's reimbursement rate adjustment based on chemical generic grouping in 2001. This research also demonstrates the use of micro-level longitudinal data to generate policy-relevant information. The research can be used to improve efficiency of health care resource use. METHODS: We chose the three most-used classes of cardiovascular drugs for this investigation: beta blocking agents, calcium channel blockers mainly with vascular effects, and plain ACE inhibitors. For each drug class, we investigated changes in daily expense, consumption volume, and total expenditures from a pre-action period to a corresponding post-action period. We compared an exposure or "intervention" group of patients targeted by the action with a comparisonor "control" group of patients not targeted by the action. The data sources are a longitudinal database for 200,000 NHI enrolees, corresponding NHI registration data of health care facilities, and an archive recording all historical data on the reimbursement rates of drugs covered by the NHI. We adopted a fixed effects linear regression model to control for unobserved heterogeneity among patient-hospital groups. Additional descriptive statistics were applied to examine whether any inappropriate consumption of drugs in the three classes existed. RESULTS: The daily drug expense significantly decreased from the pre-action period to the post-action period for the exposure group. The average magnitudes of the decreases for the three classes of drugs mentioned above were 14.8%, 5.8% and 5.8%, respectively. In contrast, there was no reduction for the comparison group. The number of days of the prescription increased significantly from the pre- to the post-action period for both exposure and comparison groups. The total expense also significantly increased for both patient groups. For the exposure group, the average magnitudes of the growth in the total expenditure for the three classes of drugs were 47.7%, 60.0% and 55.3%, respectively. For the comparison group, they were 91.6%, 91.6% and 63.2%, respectively. After the action, approximately 50% of patients obtained more than 180 days of prescription drugs for a six-month period. CONCLUSION: The 2001 price adjustment action, based on generic grouping, significantly reduced the daily expense of each of the three classes of cardiovascular drugs. However, in response to this policy change, hospitals in Taiwan tended to greatly expand the volume of drugs prescribed for their regular patients. Consequently, the total expenditures for the three classes of drugs grew substantially after the action. These knock-on effects weakened the capability of the price adjustment action to control total pharmaceutical expenditures. This means that no saved resources were available for other health care uses. Such expansion of pharmaceutical consumption might also lead to inefficient use of the three drug classes: a large proportion of patients obtained more than one day of drugs per day in the post-action period, suggesting manipulation to increase reimbursement and offset price controls. We recommend that Taiwan's government use the NHI data to establish a monitoring system to detect inappropriate prescription patterns before implementing future policy changes. Such a monitoring system could then be used to deter hospitals from abusing their prescription volumes, making it possible to more effectively save health care resources by reducing drug reimbursement rates.


Asunto(s)
Enfermedades Cardiovasculares/tratamiento farmacológico , Costos de los Medicamentos , Medicamentos Genéricos/economía , Tabla de Aranceles , Gastos en Salud/estadística & datos numéricos , Antagonistas Adrenérgicos beta/economía , Inhibidores de la Enzima Convertidora de Angiotensina/economía , Bloqueadores de los Canales de Calcio/economía , Enfermedades Cardiovasculares/economía , Gastos en Salud/tendencias , Humanos , Modelos Lineales , Taiwán
18.
BMC Public Health ; 8: 67, 2008 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-18284702

RESUMEN

BACKGROUND: Although many studies have investigated the negative effects of parental smoking on children and Taiwan has started campaigns to promote smoke-free homes, little is known about the smoking behaviours of Taiwanese parents during the childbearing period. To help fill the gap, this study investigated Taiwanese parents' smoking behaviours before, during and after the birth of their children, particularly focusing on smoking cessation during pregnancy and relapse after childbirth. METHODS: We used data from the Survey of Health Status of Women and Children, conducted by Taiwan's National Health Research Institutes in 2000. After excluding survey respondents with missing information about their smoking behaviours, our sample consisted of 3,109 women who were married at the time of interview and had at least one childbearing experience between March 1, 1995 and February 28, 1999. Data on parental smoking behaviour in the six months before pregnancy, during pregnancy, and in the first year after childbirth were extracted from the survey and analysed by descriptive statistics as well as logistic regression. RESULTS: Four percent of the mothers and sixty percent of the fathers smoked before the conception of their first child. The educational attainment and occupation of the parents were associated with their smoking status before the first pregnancy in the family. Over 80% of smoking mothers did not quit during pregnancy, and almost all of the smoking fathers continued tobacco use while their partners were pregnant. Over two thirds of the women who stopped smoking during their pregnancies relapsed soon after childbirth. Very few smoking men stopped tobacco use while their partners were pregnant, and over a half of those who quit started to smoke again soon after their children were born. CONCLUSION: Among Taiwanese women who had childbearing experiences in the late 1990s, few smoked. Of those who smoked, few quit during pregnancy. Most of those who quit relapsed in the first year after childbirth. The smoking prevalence was high among the husbands of these Taiwanese women, and almost all of these smoking fathers continued tobacco use while their partners were pregnant. It is important to advocate the benefits of a smoke-free home to Taiwanese parents-to-be and parents with young children, especially the fathers. The government should take advantage of its free prenatal care and well-child care services to do this. In addition to educational campaigns through the media, the government can request physicians to promote smoke-free homes when they deliver prenatal care and well-child care. This could help reduce young children's health risks from their mothers' smoking during pregnancy and second-hand smoke at home.


Asunto(s)
Padres/psicología , Cese del Hábito de Fumar/estadística & datos numéricos , Fumar/epidemiología , Adulto , Femenino , Encuestas Epidemiológicas , Humanos , Entrevistas como Asunto , Modelos Logísticos , Masculino , Parto , Embarazo , Prevalencia , Estudios Retrospectivos , Fumar/psicología , Clase Social , Taiwán/epidemiología
19.
Psychiatr Genet ; 17(6): 333-8, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18075473

RESUMEN

OBJECTIVE: A region at chromosome 22q11.21 has been reported to potentially harbor a candidate gene for schizophrenia, ZDHHC8 (zinc finger, DHHC domain containing 8; also annotated as KIAA1292) in a number of studies. This finding has been replicated in Han Chinese, but not in other ethnicity-specific studies. For further support from within the Han Chinese ethnic group, we selected two single nucleotide polymorphisms (SNP) located at the distal 5'-end (rs1633445; intron 10 of HpaII tiny fragments locus 9C, HTF9C) and the intron 4 (rs175174) of ZDHHC8 gene to test if these were associated with schizophrenia in a study sample of Taiwan. METHODS: A total of 218 schizophrenia families with at least two affected siblings participated in this study. These two SNPs were genotyped using matrix-assisted laser desorption/localization ionization time of flight (MALDI-TOF) mass spectrometry. RESULTS: Significant associations with schizophrenia were not shown from these two SNPs. After stratifying schizophrenia according to the deficit and the nondeficit of sustained attention assessed by the Continuous Performance Test, the rs1633445 showed significant association with schizophrenia in the presence of a deficit in sustained attention (P<0.04). CONCLUSION: SNP rs1633445 of the HTF9C gene may be associated with a deficit in sustained attention within schizophrenia, in a Taiwanese cohort. The deficit of sustained attention may be an endophenotype of schizophrenia, and warrants further study.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/genética , Cromosomas Humanos Par 22 , Polimorfismo de Nucleótido Simple , Proteínas/genética , Esquizofrenia/genética , Pueblo Asiatico/genética , Trastorno por Déficit de Atención con Hiperactividad/clasificación , Mapeo Cromosómico , Femenino , Humanos , Intrones , Masculino , Núcleo Familiar , Esquizofrenia/clasificación , Esquizofrenia/complicaciones , Hermanos , Taiwán
20.
Schizophr Res ; 93(1-3): 391-8, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17407805

RESUMEN

Several linkage studies have shown significant linkage of schizophrenia to chromosome 6p region, which includes the positional candidate genes, Dystrobrevin-binding protein 1 (DTNBP1). The aim was to examine the association evidence of the candidate gene in 693 Taiwanese families with at least two affected siblings of schizophrenia. We genotyped nine SNPs of this gene with average intermarker distance of 17 kb. Intermarker linkage disequilibrium was calculated with GOLD. Single locus and haplotype association analyses were performed with TRANSMIT program. We found no significant association between schizophrenia and DTNBP1 either through single locus or haplotype analyses. We failed to replicate the association evidence between DTNBP1 and schizophrenia and this gene may not play a major role in the etiology of schizophrenia in this Taiwanese family sample.


Asunto(s)
Pueblo Asiatico/genética , Proteínas Portadoras/genética , Esquizofrenia/genética , Adulto , Cromosomas Humanos Par 6 , Disbindina , Proteínas Asociadas a la Distrofina , Femenino , Marcadores Genéticos/genética , Predisposición Genética a la Enfermedad/genética , Genotipo , Haplotipos , Humanos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Esquizofrenia/etnología , Hermanos/psicología , Taiwán
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