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1.
J Synchrotron Radiat ; 28(Pt 3): 977-986, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33950006

RESUMEN

We report on the development of a high-resolution and highly efficient beamline for soft X-ray resonant inelastic X-ray scattering (RIXS) located at the Taiwan Photon Source. This beamline adopts an optical design that uses an active grating monochromator (AGM) and an active grating spectrometer (AGS) to implement the energy compensation principle of grating dispersion. Active gratings are utilized to diminish defocus, coma and higher-order aberrations, as well as to decrease the slope errors caused by thermal deformation and optical polishing. The AGS is mounted on a rotatable granite platform to enable momentum-resolved RIXS measurements with scattering angles over a wide range. Several high-precision instruments developed in-house for this beamline are described briefly. The best energy resolution obtained from this AGM-AGS beamline was 12.4 meV at 530 eV, achieving a resolving power of 4.2 × 104, while the bandwidth of the incident soft X-rays was kept at 0.5 eV. To demonstrate the scientific impact of high-resolution RIXS, we present an example of momentum-resolved RIXS measurements on a high-temperature superconducting cuprate, i.e. La2-xSrxCuO4. The measurements reveal the A1g buckling phonons in superconducting cuprates, opening a new opportunity to investigate the coupling between these phonons and charge-density waves.

2.
Phys Rev Lett ; 123(23): 233602, 2019 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-31868475

RESUMEN

Virtual photons can mediate interaction between atoms, resulting in an energy shift known as a collective Lamb shift. Observing the collective Lamb shift is challenging, since it can be obscured by radiative decay and direct atom-atom interactions. Here, we place two superconducting qubits in a transmission line terminated by a mirror, which suppresses decay. We measure a collective Lamb shift reaching 0.8% of the qubit transition frequency and twice the transition linewidth. We also show that the qubits can interact via the transmission line even if one of them does not decay into it.

3.
Osteoporos Int ; 28(4): 1167-1178, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28083669

RESUMEN

Our systematic review and meta-analysis of observational studies indicated that the use of antipsychotics was associated with a nearly 1.5-fold increase in the risk of fracture. First-generation antipsychotics (FGAs) appeared to carry a higher risk of fracture than second-generation antipsychotics (SGAs). INTRODUCTION: The risk of fractures associated with the use of antipsychotic medications has inconsistent evidence between different drug classes. A systematic review and meta-analysis was conducted to evaluate whether there is an association between the use of antipsychotic drugs and fractures. METHODS: Searches were conducted through the PubMed and EMBASE databases to identify observational studies that had reported a quantitative estimate of the association between use of antipsychotics and fractures. The summary risk was derived from random effects meta-analysis. RESULTS: The search yielded 19 observational studies (n = 544,811 participants) with 80,835 fracture cases. Compared with nonuse, use of FGAs was associated with a significantly higher risk for hip fractures (OR 1.67, 95% CI, 1.45-1.93), and use of second generation antipsychotics (SGAs) was associated with an attenuated but still significant risk for hip fractures (OR 1.33, 95% CI, 1.11-1.58). The risk of fractures associated with individual classes of antipsychotic users was heterogeneous, and odds ratios ranged from 1.24 to 2.01. Chlorpromazine was associated with the highest risk (OR 2.01, 95% CI 1.43-2.83), while Risperidone was associated with the lowest risk of fracture (OR 1.24, 95% CI 0.95-1.83). CONCLUSIONS: FGA users were at a higher risk of hip fracture than SGA users. Both FGAs and SGAs were associated with an increased risk of fractures, especially among the older population. Therefore, the benefit of the off-label use of antipsychotics in elderly patients should be weighed against any risks for fracture.


Asunto(s)
Antipsicóticos/efectos adversos , Fracturas Osteoporóticas/inducido químicamente , Fracturas del Fémur/inducido químicamente , Fracturas de Cadera/inducido químicamente , Humanos , Medición de Riesgo/métodos
4.
J Synchrotron Radiat ; 21(Pt 2): 325-32, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24562553

RESUMEN

The design, construction and commissioning of a beamline and spectrometer for inelastic soft X-ray scattering at high resolution in a highly efficient system are presented. Based on the energy-compensation principle of grating dispersion, the design of the monochromator-spectrometer system greatly enhances the efficiency of measurement of inelastic soft X-rays scattering. Comprising two bendable gratings, the set-up effectively diminishes the defocus and coma aberrations. At commissioning, this system showed results of spin-flip, d-d and charge-transfer excitations of NiO. These results are consistent with published results but exhibit improved spectral resolution and increased efficiency of measurement. The best energy resolution of the set-up in terms of full width at half-maximum is 108 meV at an incident photon energy tuned about the Ni L3-edge.

5.
Schizophr Res ; 254: 68-75, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36801516

RESUMEN

This study aimed to identify risk factors for involuntary referral by police to emergency room (ER) psychiatric services for community-based patients with a mental illness via a generalized estimating equation (GEE) analysis. The analysis was based on data from the Management Information System of Psychiatric Care (MISPC) system for patients with a severe mental illness in Taipei, Taiwan and registered referral records of the police. Data on 6378 patients aged ≥20 years were used in this study, including 164 patients who were involuntarily referred to the ER by the police and 6214 patients who were not during the period of January 1, 2018 to December 31, 2020. GEEs were utilized to explore possible risk factors of repeated involuntary referral to ER psychiatric services for patients with a severe mental illness. The logistic regressions indicated that patients defined as "severe" according to the Mental Health Act of Taiwan (crude odds ratio (OR): 3.840, 95 % confidence interval (CI): 2.407-6.126), with a disability (crude OR: 3.567, 95 % CI: 1.339-9.501), with two or more family members with a psychiatric disorder (crude OR: 1.598, 95 % CI: 1.002-2.548), with a history of a suicide attempt (crude OR: 25.582, 95 % CI: 17.608-37.167), and with a history of domestic violence (crude OR: 16.141, 95 % CI: 11.539-22.579) were positively associated with involuntary referral to ER psychiatric services. However, age (crude OR: 0.971, 95 % CI: 0.960-0.983) and the MISPC score (crude OR: 0.834, 95 % CI: 0.800-0.869) were inversely associated with involuntary referral to ER psychiatric services. After adjusting for demographics and potential confounders, we found that patients defined as "severe" (Exp (ß): 3.236), with a disability (Exp (ß): 3.715), with a history of a suicide attempt (Exp (ß): 8.706), and with a history of domestic violence (Exp (ß): 8.826), as well as age (Exp (ß): 0.986) and the MISPC score (Exp (ß): 0.902) remained significantly associated with repeated involuntary referral to ER psychiatric services. In conclusion, community-based mentally ill patients with a history of a suicide attempt, with a history of domestic violence, with a severe illness, and with a profound level of disability were highly associated with involuntary referral to ER psychiatric services. We suggest that community mental health case managers identify significant factors associated with involuntary referral to ER psychiatric services to accordingly arrange case management plans.


Asunto(s)
Servicios de Urgencia Psiquiátrica , Trastornos Mentales , Humanos , Trastornos Mentales/epidemiología , Trastornos Mentales/terapia , Trastornos Mentales/psicología , Policia , Derivación y Consulta , Factores de Riesgo , Adulto
7.
J Viral Hepat ; 18(7): e315-24, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21692943

RESUMEN

Chronic hepatitis C virus (HCV) infection is associated with chronic inflammation of liver, which leads to the development of cirrhosis and hepatocellular carcinoma (HCC). Because of severe side effects and only a 50-70% cure rate in genotype 1 HCV-infected patients upon current standard treatment with pegylated interferon-α plus ribavirin, new therapeutic regimens are still needed. San-Huang-Xie-Xin-Tang (SHXT) is a transitional Chinese herbal formula, composed of Rhei rhizoma, Scutellaria radix and Coptidis rhizome, and possesses anti-inflammatory effect. Here, we describe a (+)-catechin-containing fraction extracted from SHXT, referred as SHXT-frC, exhibited effective inhibition of HCV replication, with selectivity index value (SI; CC50 /EC50) of 84, and displayed synergistic anti-HCV effects when combined with interferon-α, HCV protease inhibitor telaprevir or polymerase inhibitor 2'-C-methylcytidine. The activation of factor-κB (NF-κB) and cyclooxygenase-2 (COX-2) signalling pathway has particular relevance to HCV-associated HCC. SHXT-frC treatment also caused a concentration-dependent decrease in the induction of COX-2 and NF-κB expression caused by either HCV replication or HCV NS5A protein. Collectively, SHXT-frC could be an adjuvant treatment for patients with HCV-induced liver diseases.


Asunto(s)
Inhibidores de la Ciclooxigenasa 2/farmacología , Ciclooxigenasa 2/biosíntesis , Medicamentos Herbarios Chinos/farmacología , Hepacivirus/efectos de los fármacos , Replicación Viral/efectos de los fármacos , Antivirales/farmacología , Catequina/farmacología , Línea Celular , Ciclooxigenasa 2/genética , Citidina/análogos & derivados , Citidina/uso terapéutico , Quimioterapia Combinada , Hepacivirus/fisiología , Humanos , Interferón-alfa/uso terapéutico , FN-kappa B/biosíntesis , FN-kappa B/metabolismo , Oligopéptidos/uso terapéutico , Transducción de Señal/efectos de los fármacos , Proteínas no Estructurales Virales/metabolismo
8.
Phys Rev Lett ; 107(13): 135101, 2011 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-22026866

RESUMEN

Cyclotron harmonic interactions are a key physics issue of critical importance to the generation of terahertz radiation via the electron cyclotron maser instability for practical magnetic field strengths. We present an inherent mechanism, as well as a deciding factor, which governs the competition between low- and high-harmonic interactions. Multimode simulations reveal the physical process in which a significant advantage develops for the lower-harmonic interaction, which eventually dominates in the fully nonlinear stage. The results also suggest a start-up scenario for persistent higher-harmonic operation.

9.
Int J Obes (Lond) ; 33(11): 1309-17, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19752878

RESUMEN

BACKGROUND: Metabolic syndrome (MS) is considered a cause of abnormal deposition of fat into hepatocytes, which might be associated with hepatic steatosis or abnormal liver function. OBJECTIVE: The aim of this study was to explore the factors associated with MS and the relationship between MS and abnormal aspartate aminotransferase (AST), alanine aminotransferase (ALT) and gamma-glutamyl transferase (GGT) levels in Taiwanese subjects without chronic hepatitis B (CHB) or C (CHC). SUBJECTS: We enrolled 2539 Taiwanese adults without CHB or CHC (age range: 16-88 years old) and investigated the factors related to MS using the NCEP-ATP (National Cholesterol Education Program-Adult Treatment Panel) III criteria; body mass index (BMI) was measured using Asia-Pacific criteria. RESULTS: The prevalence rate of MS in Taiwanese adults without CHB or CHC was 16.9% using the modified ATP III criteria and 15.4% using the International Diabetes Federation criteria. Males had a significantly higher prevalence rate than females (P<0.001), and subjects with MS were significantly older and had significantly higher BMI values and AST, ALT and GGT levels (all P<0.001). In univariate analyses, the abnormality of liver function test results were related to gender, level of fasting sugar, systolic blood pressure, triglyceride, high-density lipoprotein, BMI and MS (all P<0.05). Multivariate analysis showed that the male gender, a higher BMI value and MS were related to abnormal liver function test results. The cutoff value for ALT in relation to MS is 31 IU l(-1) for male and 18 IU l(-1) for female. CONCLUSION: The prevalence of MS in Taiwanese adults without hepatitis B or C was found to be high, and MS and BMI were identified as being related to abnormal liver function test results in these adults.


Asunto(s)
Alanina Transaminasa/sangre , Aspartato Aminotransferasas/sangre , Hepatopatías/enzimología , Síndrome Metabólico/enzimología , Obesidad/enzimología , gamma-Glutamiltransferasa/sangre , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Femenino , Hepatitis B Crónica , Hepatitis C Crónica , Humanos , Hepatopatías/epidemiología , Pruebas de Función Hepática , Masculino , Síndrome Metabólico/epidemiología , Persona de Mediana Edad , Obesidad/epidemiología , Prevalencia , Factores de Riesgo , Taiwán/epidemiología , Adulto Joven
11.
Science ; 163(3870): 925-6, 1969 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-5763874

RESUMEN

The sulfur atom in position 6 of deamino-oxytocin (1-beta-mercapto-propionic acid-oxytocin) was replaced by selenium. The crystals of the resulting deamino-6-seleno-oxytocin are similar to those of the "wet" form of deamino-oxytocin, but they are stable upon prolonged exposure to air.


Asunto(s)
Oxitocina , Selenio , Cristalización , Agua , Difracción de Rayos X
12.
Acta Psychiatr Scand ; 120(4): 274-80, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19426161

RESUMEN

OBJECTIVE: Because of ethnic differences in metabolic syndrome (MS) criteria, this study aimed to investigate the MS prevalence among patients with schizophrenia or schizoaffective disorder in Taiwan. METHOD: We recruited 650 patients with schizophrenia or schizoaffective disorder from 36 psychiatric institutions. The MS prevalence was assessed based on the modified Adult Treatment Panel (ATP) III criteria for Asians. RESULTS: The overall MS prevalence was 34.9%, with 38.9% in female and 31.5% in male patients respectively. The difference of MS prevalence between our sample and the general population was marked in male patients under 40 years of age and in female patients under 50 years old. Body mass index > or =24 and age over 40 years old are two important risk factors of MS. Female and polypharmacy had marginal significance with the presence of MS. CONCLUSION: Patients with schizophrenia or schizoaffective disorder in Taiwan had a high prevalence of MS, which appeared early in their lives.


Asunto(s)
Síndrome Metabólico/epidemiología , Trastornos Psicóticos/epidemiología , Esquizofrenia/epidemiología , Grasa Abdominal , Antipsicóticos/uso terapéutico , Índice de Masa Corporal , Femenino , Humanos , Hipertensión/diagnóstico , Hipertensión/epidemiología , Masculino , Persona de Mediana Edad , Obesidad/epidemiología , Prevalencia , Trastornos Psicóticos/tratamiento farmacológico , Esquizofrenia/tratamiento farmacológico , Taiwán/epidemiología , Circunferencia de la Cintura
13.
Oncogene ; 26(3): 467-76, 2007 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-16878157

RESUMEN

To identify genes that could potentially serve as molecular therapeutic markers for human head and neck cancer (HNC), we employed differential display analysis to compare the gene expression profiles between HNC and histopathologically normal epithelial tissues. Using reverse transcription-polymerase chain reaction and Western blot analysis, desmoglein 3 (DSG3) was identified as being differentially expressed at both the RNA and protein levels. Of 56 patients assayed, 34 (61%) had overexpression of DSG3, which correlated statistically with T stage (P=0.009), N stage (P=0.047), overall stage (P=0.011), tumor depth (P=0.009) and extracapsular spread in lymph nodes (P=0.044), suggesting that DSG3 participates in carcinogenesis of HNC. Consistent with the clinical findings, inhibition of DSG3 by RNA interference (RNAi) significantly reduced cell growth and colony formation to 57-21% in three HNC cell lines. Use of an in vitro wound healing and Matrigel invasion assays, we found that cell migration and invasive ability were also inhibited to 30-48% in three cell lines tested. An in vivo xenograft study showed that administration of DSG3-RNAi plasmid significantly inhibited tumor growth for 2 months in BALB/C nude mice. In conclusion, DSG3 is identified overexpressed in HNC, with the degree of overexpression associated with clinicopathologic features of the tumor. Inhibition of DSG3 significantly suppresses carcinogenic potential in cellular and in vivo animal studies. These findings suggest that DSG3 is a potential molecular target in the development of adjuvant therapy for HNC.


Asunto(s)
Desmogleína 3/metabolismo , Regulación Neoplásica de la Expresión Génica , Neoplasias de Cabeza y Cuello/metabolismo , Neoplasias de la Boca/patología , Animales , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Movimiento Celular , Colágeno/metabolismo , Desmogleína 3/antagonistas & inhibidores , Desmogleína 3/genética , Combinación de Medicamentos , Perfilación de la Expresión Génica , Neoplasias de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/patología , Humanos , Células KB/trasplante , Laminina/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias de la Boca/metabolismo , Invasividad Neoplásica/patología , Plásmidos , Proteoglicanos/metabolismo , ARN Interferente Pequeño/farmacología , Tasa de Supervivencia , Ensayo de Tumor de Célula Madre , Ensayos Antitumor por Modelo de Xenoinjerto
14.
Int J Obes (Lond) ; 32(2): 268-74, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17878891

RESUMEN

OBJECTIVE: Epicardial and abdominal adipose tissues have recently been demonstrated to play inflammatory roles in coronary atherosclerosis. We sought to compare tissue adipocytokine levels of these two anatomically distinct adipose stores in patients with and without coronary artery diseases (CAD). DESIGN: Samples of abdominal and epicardial fat tissues were harvested to detect the levels of adipocytokines and proinflammatory mediators. SUBJECTS: Forty-six patients with CAD who underwent coronary artery bypass surgery and 12 non-CAD control subjects who underwent other types of open-heart surgery. MEASUREMENTS: Tissue levels of adipocytokines (adiponectin, leptin and visfatin) and proinflammatory mediators (tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6)) were determined by enzyme-linked immunosorbent assay. RESULTS: Tissue levels of TNF-alpha, IL-6, leptin and visfatin were significantly higher in CAD patients relative to control subjects. In addition, significantly higher tissue levels of these four cytokines from abdominal fat depots were found compared to those from epicardial fat in CAD patients. Conversely, in comparison with control subjects, tissue levels of adiponectin were significantly reduced in CAD patients with a significantly lower tissue levels of abdominal than epicardial fat depots demonstrated. CONCLUSION: Abdominal adiposity may play more significant role than epicardial fat in the pathogenesis of coronary atherosclerosis.


Asunto(s)
Adipoquinas/metabolismo , Tejido Adiposo/metabolismo , Enfermedad de la Arteria Coronaria/metabolismo , Mediadores de Inflamación/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Enfermedad de la Arteria Coronaria/etiología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Obesidad/metabolismo
15.
Oncogene ; 37(5): 589-600, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-28991224

RESUMEN

Growing evidence indicates that resistin-an obesity-related cytokine-is upregulated in breast cancer patients, yet its impact on breast cancer behavior remains to be ascertained. Similarly, Toll-like receptor 4 (TLR4) has been implicated in breast cancer progression, however, its clinically relevant endogenous ligand remains elusive. In this study, we observed that high serum resistin levels in breast cancer patients positively correlated with tumor stage, size and lymph node metastasis. These findings were replicated in animal models of breast cancer tumorigenesis and metastasis. Resistin was found to promote epithelial-mesenchymal transition and stemness in breast cancer cells-mechanisms critical to tumorigenesis and metastasis-through a TLR4/nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB)/signal transducer and activator of transcription 3 (STAT3) signaling pathway and negated by TLR4-specific antibody and antagonist. These findings provide clear evidence that resistin is a clinically relevant endogenous ligand for TLR4, which promotes tumor progression via TLR4/NF-κB/STAT3 signaling, providing insights into a novel therapeutic target in breast cancer.


Asunto(s)
Neoplasias de la Mama/patología , Transición Epitelial-Mesenquimal , Células Madre Neoplásicas/patología , Resistina/metabolismo , Receptor Toll-Like 4/metabolismo , Animales , Mama/patología , Neoplasias de la Mama/sangre , Carcinogénesis/patología , Línea Celular Tumoral , Progresión de la Enfermedad , Femenino , Humanos , Metástasis Linfática , Persona de Mediana Edad , FN-kappa B , Estadificación de Neoplasias , Resistina/sangre , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Regulación hacia Arriba , Ensayos Antitumor por Modelo de Xenoinjerto , Pez Cebra
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