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1.
J Viral Hepat ; 22(2): 77-84, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25424771

RESUMEN

Hepatitis B virus (HBV) infection is a major cause of cirrhosis and hepatocellular carcinoma worldwide. On the basis of virus-host interactions, the natural history of HBV carriers can be divided into four chronological phases. In the first immune tolerance phase, HBV carriers are positive for hepatitis B e antigen (HBeAg) and have high HBV replication activity, normal ALT levels as well as minimal liver disease. Ample evidence has shown that patients in the immune tolerance phase have very low viral evolution and minimal risk of fibrosis progression. However, recent immunological studies argued that HBV-specific immune responses already exist in a proportion of immune-tolerant patients and the immune activities are comparable to those in the immune clearance phase. Regarding antiviral therapy, whether these immune-tolerant patients are indicated for treatment remains debated. Previous studies showed that HBeAg-positive patients with normal or near-normal ALT levels, who are assumed to be in the immune tolerance phase, have a lower HBeAg seroconversion rate receiving either pegylated interferon or nucleos(t)ide analogue treatment. The latest clinical trial focusing on-treatment response of immune-tolerant patients with tenofovir disoproxil fumarate-based therapy also confirmed the results. The HBeAg seroconversion rates are <5% at 4 years of treatment. Considering the minimal risk of disease progression and low treatment response rates in immune-tolerant patients, current antiviral therapy should not be recommended unless the patients have advanced liver fibrosis. In addition, novel agents targeting the HBV template known as covalently closed circular DNA and aiming to reduce or eliminate it are urgently required.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis B Crónica/tratamiento farmacológico , Hepatitis B Crónica/inmunología , Adenina/análogos & derivados , Adenina/uso terapéutico , Quimioterapia/métodos , Hepatitis B Crónica/virología , Humanos , Interferones/uso terapéutico , Nucleótidos/uso terapéutico , Organofosfonatos/uso terapéutico , Tenofovir
2.
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.

3.
Phys Rev Lett ; 110(2): 027202, 2013 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-23383936

RESUMEN

We investigate the magnetic coupling of Ni centers embedded in two-dimensional metal-coordination networks self-assembled from 7,7,8,8-tetracyanoquinodimethane (TCNQ) molecules on Ag(100) and Au(111) surfaces. X-ray magnetic circular dichroism measurements show that single Ni adatom impurities assume a spin-quenched configuration on both surfaces, while Ni atoms coordinating to TCNQ ligands recover their magnetic moment and exhibit ferromagnetic coupling. The valence state and the ferromagnetic coupling strength of the Ni coordination centers depend crucially on the underlying substrate due to the different charge state of the TCNQ ligands on the two surfaces. The results suggest a superexchange coupling mechanism via the TCNQ ligands.

4.
J Viral Hepat ; 19(2): e48-57, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22239526

RESUMEN

The metabolic syndrome may cause disease progression in patients with chronic hepatitis B (CHB). However, the interactions between hepatitis B virus (HBV) infection and metabolic factors remain unknown. We investigated the association of HBV infection with metabolic profiles in HBV-infected and noninfected subjects. In addition, the impacts of serum HBV DNA level on metabolic profiles were studied. Initially, a case-control analysis of patients with and without chronic HBV infection was performed. The HBV group consisted of 322 patients with chronic HBV infection, and the control group consisted of 870 matched subjects without HBV infection. Fasting blood glucose, lipid profiles and adiponectin levels were compared. The results were then confirmed in a second retrospective cohort study in 122 CHB patients with serum HBV DNA levels and HOMA-IR index values. In the case-control analysis, the HBV group had significantly higher serum adiponectin, but lower triglyceride (TG) and high-density lipoprotein cholesterol (HDL) levels than the control group. These relationships already existed in subjects younger than 45 years of age and were modified by serum alanine aminotransferase (ALT) levels. In the retrospective cohort, serum HBV DNA levels were negatively proportional to TG levels, but not to other metabolic parameters. Moreover, this relationship was significant only in subjects with higher ALT levels. Compared with healthy adults, patients with chronic HBV infection have significantly higher serum adiponectin, but lower TG and HDL levels. These relationships are modified by ALT levels and already exist in middle-age patients with chronic HBV infection, implying HBV may interact with host metabolism.


Asunto(s)
Análisis Químico de la Sangre , Hepatitis B/fisiopatología , Metaboloma , Adulto , Anciano , Alanina Transaminasa/sangre , Estudios de Casos y Controles , Estudios de Cohortes , ADN Viral/sangre , Femenino , Virus de la Hepatitis B/aislamiento & purificación , Humanos , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Carga Viral
5.
J Viral Hepat ; 18(10): e482-90, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21914067

RESUMEN

Hepatitis B virus (HBV) genotypes/mutants are known to affect natural outcomes. The virologic differences among HBV genotype, precore and basal core promoter (BCP) mutations were investigated. HBV strains were isolated from 18 hepatitis B e antigen (HBeAg)-positive patients (nine genotype B and nine genotype C). All had precore and BCP wild-type sequences. After cloning of full-length HBV genome, the effects of viral genotype, precore and BCP mutations singly or additively on the expression of viral DNA and antigens were investigated by mutagenesis and transfection assays in Huh7 cells. Significant findings included the following: (i) expression of intracellular core protein increased when precore or BCP mutation was introduced in genotype C strains; (ii) expression of intracellular surface protein was lower in genotype C precore wild-type strain compared with genotype B; (iii) precore mutation was associated with a lower extracellular expression level of HBV DNA; (iv) secretion of hepatitis B surface antigen in genotype C was lower than that in genotype B; and (v) secretion of HBeAg in genotype B was lower than that in genotype C. No additive effect was observed by combining precore and BCP mutations. Hence, HBV genotype and precore/BCP mutations correlate with intrahepatic expression of viral antigens in vitro.


Asunto(s)
ADN Viral/biosíntesis , Antígenos de la Hepatitis B/biosíntesis , Virus de la Hepatitis B/genética , Mutación , Regiones Promotoras Genéticas , Adulto , Línea Celular , Análisis Mutacional de ADN , Femenino , Genotipo , Hepatitis B/virología , Antígenos e de la Hepatitis B/sangre , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/aislamiento & purificación , Hepatocitos/virología , Humanos , Masculino
6.
Aliment Pharmacol Ther ; 47(11): 1480-1489, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29601647

RESUMEN

BACKGROUND: Fibrosis-4 index (FIB-4) is a surrogate marker for hepatic fibrosis in hepatitis B virus (HBV) carriers. AIM: To investigate whether FIB-4 index stratifies the risks of adverse liver events. METHODS: A total of 2075 treatment-naïve, noncirrhotic the patients with chronic HBV infection were included. Most of them (82.1%) were HBeAg-negative patients and their baseline FIB-4 levels were explored to stratify the risks of cirrhosis, cirrhosis-related complications and liver-related mortality. RESULTS: During a mean follow-up period of 15.47 years, we found a higher baseline FIB-4 index was associated with increased incidence rates of cirrhosis in addition to the common host and viral factors. Patients with FIB-4 >1.29, compared to those with FIB-4 <1.29, were associated with increased risks of cirrhosis, cirrhosis-related complications and liver-related mortality with the hazard ratio (95% confidence interval) of 6.19 (4.76-8.05), 6.88, (3.68-12.86) and 7.79, (4.54-13.37) respectively. Within the first 3 years of follow-up, FIB-4 remained stable and its kinetics were consistently associated with the develoopment of adverse liver events. Furthermore, FIB-4 index of 1.29 was able to stratify all the risks of adverse liver events even in HBeAg-negative patients with a low risk of disease progression (HBV DNA <2000 IU/mL, HBsAg <1000 IU/mL and ALT <40 U/L). Only 1 patient with FIB-4 index <1.29 developed cirrhosis but not other events within 15 years of follow-up. CONCLUSIONS: In noncirrhotic patients with chronic HBV infection, a higher FIB-4 index was associated with increased risks of adverse liver events. FIB-4 index <1.29 is useful for the prediction of the lowest risks of disease progression.


Asunto(s)
Virus de la Hepatitis B , Hepatitis B Crónica/sangre , Hepatitis B Crónica/mortalidad , Cirrosis Hepática/sangre , Cirrosis Hepática/mortalidad , Adulto , Biomarcadores/sangre , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis B Crónica/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Mortalidad/tendencias , Valor Predictivo de las Pruebas , Factores de Riesgo
7.
Aliment Pharmacol Ther ; 47(12): 1690-1698, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29665069

RESUMEN

BACKGROUND: Data are limited regarding the effectiveness and safety of generic velpatasvir plus sofosbuvir (VEL/SOF) for hepatitis C virus (HCV) in patients with or without human immunodeficiency virus (HIV) coinfection. AIM: To evaluate the effectiveness and safety of generic VEL/SOF-based therapy for HCV infection in patients with or without HIV coinfection in Taiwan. METHODS: Sixty-nine HIV/HCV-coinfected and 159 HCV-monoinfected patients receiving 12 weeks of generic VEL/SOF with or without ribavirin (RBV) for HCV were prospectively enrolled. The anti-viral responses and the adverse events (AEs) were compared between the two groups. The characteristics potentially related to sustained virological response 12 weeks off therapy (SVR12 ) were analysed. RESULTS: The SVR12 was achieved in 67 HIV/HCV-coinfected patients (97.1%; 95% CI: 90.0%-99.2%) and in 156 HCV-monoinfected patients (98.1%; 95% CI: 94.6%-99.4%) receiving VEL/SOF-based therapy, respectively. The SVR12 rates were comparable between HIV/HCV-coinfected and HCV-monoinfected patients, regardless of pre-specified baseline characteristics. One hundred twenty-two (53.5%) and seven (3.1%) patients had baseline resistance-associated substitutions (RASs) in HCV NS5A and NS5B regions, but the SVR12 rates were not affected by the presence or absence of RASs. One (1.4%) and five (3.1%) patients in the HIV/HCV-coinfected and HCV-monoinfected groups had serious AEs. No patient died or discontinued treatment due to AEs. The eGFR remained stable throughout the course of treatment in HIV/HCV-coinfected patients receiving anti-retroviral therapy containing tenofovir disoproxil fumarate (TDF). CONCLUSIONS: Generic VEL/SOF-based therapy is well-tolerated and provides comparably high SVR12 rates for HCV infection in patients with and without HIV coinfection.


Asunto(s)
Antivirales/administración & dosificación , Carbamatos/administración & dosificación , Hepatitis C/tratamiento farmacológico , Compuestos Heterocíclicos de 4 o más Anillos/administración & dosificación , Sofosbuvir/administración & dosificación , Adulto , Anciano , Antivirales/uso terapéutico , Coinfección , Combinación de Medicamentos , Femenino , Infecciones por VIH/tratamiento farmacológico , Hepacivirus/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Ribavirina/uso terapéutico , Respuesta Virológica Sostenida , Taiwán , Tenofovir/uso terapéutico , Resultado del Tratamiento
8.
Biochim Biophys Acta ; 1518(3): 249-59, 2001 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-11311936

RESUMEN

The MAGUKs (membrane-associated guanylate kinase homologues) constitute a family of peripheral membrane proteins that function in tumor suppression and receptor clustering by forming multiprotein complexes containing distinct sets of transmembrane, cytoskeletal, and cytoplasmic signaling proteins. Here, we report the characterization of the human vam-1 gene that encodes a novel member of the p55 subfamily of MAGUKs. The complete cDNA sequence of VAM-1, tissue distribution of its mRNA, genomic structure, chromosomal localization, and Veli-1 binding properties are presented. The vam-1 gene is composed of 12 exons and spans approx. 115 kb. By fluorescence in situ hybridization the vam-1 gene was localized to 7p15-21, a chromosome region frequently disrupted in some human cancers. VAM-1 mRNA was abundant in human testis, brain, and kidney with lower levels detectable in other tissues. The primary structure of VAM-1, predicted from cDNA sequencing, consists of 540 amino acids including a single PDZ domain near the N-terminus, a central SH3 domain, and a C-terminal GUK (guanylate kinase-like) domain. Sequence alignment, heterologous transfection, GST pull-down experiments, and blot overlay assays revealed a conserved domain in VAM-1 that binds to Veli-1, the human homologue of the LIN-7 adaptor protein in Caenorhabditis. LIN-7 is known to play an essential role in the basolateral localization of the LET-23 tyrosine kinase receptor, by linking the receptor to LIN-2 and LIN-10 proteins. Our results therefore suggest that VAM-1 may function by promoting the assembly of a Veli-1 containing protein complex in neuronal as well as epithelial cells.


Asunto(s)
Proteínas Portadoras/metabolismo , Nucleósido-Fosfato Quinasa/genética , Secuencia de Aminoácidos , Secuencia de Bases , Encéfalo/metabolismo , Mapeo Cromosómico , Clonación Molecular , Guanilato-Quinasas , Humanos , Riñón/metabolismo , Masculino , Proteínas de la Membrana , Datos de Secuencia Molecular , Nucleósido-Fosfato Quinasa/química , Nucleósido-Fosfato Quinasa/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Mensajero/metabolismo , Alineación de Secuencia , Testículo/metabolismo , Transfección , Proteínas de Transporte Vesicular
9.
Aliment Pharmacol Ther ; 41(10): 949-60, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25809540

RESUMEN

BACKGROUND: Clearance of hepatitis B surface antigen (HBsAg) indicates clinical control of hepatitis B virus (HBV) infection. However, little is known about the impact of viral genomic variations on HBsAg loss. METHODS: We explored the association between viral genomic factors and HBsAg loss in 2121HBeAg-negative patients. HBV pre-core stop codon (1896) and basal core promoter (BCP) (1762/1764) sequences were determined in patients with HBV DNA ≥200 IU/mL (N = 1693). The effect of HBV genotype on HBsAg loss was further validated in the whole cohort of 3445 HBsAg carriers. RESULTS: The cumulative lifetime (age 28-75 years) incidence of HBsAg loss was 50.4% in 2121 HBeAg-negative patients. We found that genotype C, but not pre-core stop codon or BCP mutants, was associated with HBsAg loss. Compared to genotype B patients, genotype C patients had higher lifetime chance of HBsAg loss, with hazard ratio of 1.8 (95% confidence interval: 1.4-2.4). Multivariable analysis showed that male sex, elevated ALT levels, lower serum HBV DNA and HBsAg levels, and genotype C infection were associated with higher chance of HBsAg loss independently. We then performed sensitivity analysis, which re-included HBeAg-positive, cirrhotic and treatment-experienced patients, and confirmed the robustness of our results in 3445 HBsAg carriers. CONCLUSION: Genotype C infection, compared to genotype B, is associated with a higher lifetime chance of HBsAg loss in Asian HBV carriers.


Asunto(s)
Portador Sano/virología , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/genética , Hepatitis B/sangre , Adulto , Anciano , Estudios de Cohortes , ADN Viral/genética , Femenino , Estudios de Seguimiento , Genotipo , Humanos , Incidencia , Masculino , Persona de Mediana Edad
10.
Gene ; 161(2): 179-82, 1995 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-7665075

RESUMEN

In order to get more information about carbon metabolite regulation pathways, cloning and sequence analysis of sucrose-regulated genes from rice-suspension-cultured cells were performed. We used a new method, mRNA differential display, to screen differentially expressed genes under conditions of 3% and no sucrose in the cultured medium. Six candidate clones were identified and sequenced. Clones SI1 and SI2 were repressed by sucrose starvation, while clones SR1, SR2, SR3 and SR4 were induced by sucrose starvation. Nucleotide sequence analysis showed that clone SR2 has 94.8% homology to the salT gene, and clones SI1 and SR3 show 88.3 and 96.9% identity, respectively, to partial cDNA sequences in the GenBank database. The results suggest that mRNA differential display provides an easy and quick way to clone genes involved in the carbon metabolite regulation pathway.


Asunto(s)
Genes de Plantas , Oryza/genética , Oryza/metabolismo , ARN Mensajero/genética , ARN de Planta/genética , Sacarosa/metabolismo , Secuencia de Bases , Clonación Molecular , Cartilla de ADN/genética , ADN Complementario/genética , ADN de Plantas/genética , Regulación de la Expresión Génica de las Plantas , Datos de Secuencia Molecular
11.
DNA Cell Biol ; 19(11): 679-88, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11098217

RESUMEN

We previously reported two novel testis-specific serine/threonine kinases, Aie1 (mouse) and AIE2 (human), that share high amino acid identities with the kinase domains of fly aurora and yeast Ipl1. Here, we report the entire intron-exon organization of the Aie1 gene and analyze the expression patterns of Aie1 mRNA during testis development. The mouse Aie1 gene spans approximately 14 kb and contains seven exons. The sequences of the exon-intron boundaries of the Aie1 gene conform to the consensus sequences (GT/AG) of the splicing donor and acceptor sites of most eukaryotic genes. Comparative genomic sequencing revealed that the gene structure is highly conserved between mouse Aie1 and human AIE2. However, much less homology was found in the sequence outside the kinase-coding domains. The Aie1 locus was mapped to mouse chromosome 7A2-A3 by fluorescent in situ hybridization. Northern blot analysis indicates that Aie1 mRNA likely is expressed at a low level on day 14 and reaches its plateau on day 21 in the developing postnatal testis. RNA in situ hybridization indicated that the expression of the Aie1 transcript was restricted to meiotically active germ cells, with the highest levels detected in spermatocytes at the late pachytene stage. These findings suggest that Aie1 plays a role in spermatogenesis.


Asunto(s)
Genes/genética , Proteínas Serina-Treonina Quinasas/genética , Secuencia de Aminoácidos , Animales , Aurora Quinasa C , Aurora Quinasas , Secuencia de Bases , Northern Blotting , Bandeo Cromosómico , Mapeo Cromosómico , ADN/química , ADN/genética , ADN/aislamiento & purificación , Exones , Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Humanos , Hibridación in Situ , Hibridación Fluorescente in Situ , Intrones , Masculino , Ratones , Ratones Endogámicos , Datos de Secuencia Molecular , ARN Mensajero/genética , ARN Mensajero/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Testículo/enzimología , Testículo/crecimiento & desarrollo
12.
DNA Cell Biol ; 17(10): 823-33, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9809744

RESUMEN

We have analyzed the general protein kinase expression profile in mouse sperm and eggs. A total of 41 different kinases were identified. In this study, we describe two novel protein kinases, designated AIE1 (mouse) and AIE2 (human), which share high amino acid identities with the serine/threonine (S/T) kinase domain of yeast Ip11, fly aurora, and frog Eg2. Mutations in Ip11 and aurora have been reported to cause abnormal chromosome segregation and centrosome separation. Both AIE1 and AIE2 contain a typical S/T kinase domain (251 aa) flanked by a short polypeptide at both ends. Two other AIE-related kinases (STK-1 and IAK1/Ayk1) were also identified in mature mouse oocytes. The central kinase domain of AIE1 revealed 77.6% and 66.3% identity with that of STK-1 and IAK1/Ayk1, but much less homology was found in the sequence outside the kinase domain. Northern blot analysis revealed that both AIE1 and AIE2 are specifically expressed in testis, whereas STK-1 and IAK1/Ayk1 are expressed in many tissues rich in proliferating cells. An in vitro kinase assay showed that AIE1 can phosphorylate casein, AIE1 itself, and an uncharacterized cellular protein (p16). The kinase activity of AIE1 can be destroyed by heat inactivation. In summary, we suggest that AIE is a new member of the S/T kinase family, which may be regulated in a fashion distinct from other AIE-related kinases.


Asunto(s)
Segregación Cromosómica , Óvulo/enzimología , Proteínas Quinasas/genética , Proteínas Serina-Treonina Quinasas/genética , Proteínas Tirosina Quinasas/genética , Espermatozoides/enzimología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Secuencia de Consenso , Drosophila/enzimología , Femenino , Homeostasis , Humanos , Masculino , Ratones , Datos de Secuencia Molecular , Especificidad de Órganos , Filogenia , Biosíntesis de Proteínas , Proteínas Quinasas/biosíntesis , Proteínas Quinasas/química , Proteínas Serina-Treonina Quinasas/biosíntesis , Proteínas Serina-Treonina Quinasas/química , Proteínas Tirosina Quinasas/biosíntesis , Proteínas Tirosina Quinasas/química , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Saccharomyces cerevisiae/enzimología , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Transcripción Genética
13.
Int J Food Microbiol ; 65(1-2): 23-6, 2001 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-11322697

RESUMEN

Samples of maize imported into Taiwan during 1997-1998 were collected and analyzed for the presence of fumonisin B1 (FB1) using high performance liquid chromatography. Eight (6.8%) of 118 samples were found to contain FB1 (334-1614 microg kg(-1)). The frequency of FB1 found in maize samples imported from Australia was 20%, followed by Thailand (10%), and USA (5.1%). In analyzing the distribution pattern, it was found that 93.2% of the samples had FB1 concentrations below 100 microg kg(-1), and only 3.4% (or four samples) were in excess of 300 microg kg(-1).


Asunto(s)
Ácidos Carboxílicos/análisis , Contaminación de Alimentos , Fumonisinas , Fusarium/metabolismo , Zea mays/microbiología , Cromatografía Líquida de Alta Presión , Taiwán
14.
Chronobiol Int ; 17(1): 43-8, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10672432

RESUMEN

The gymnotid electric fish, Eigenmannia virescens, exhibits electric discharge rhythmicity both in alternate light-dark (LD; 12 h light, 12 h dark [LD 12:12]) and in constant dark (DD) conditions. It suggests that the electric discharge rhythm is under control of the circadian clock. The free-running periods (FRPs) of electric discharge rhythms at 21 degrees C in DD are greater than, but close to, 24 h. The maximum of the electric discharge in the Eigenmannia system peaks approximately at circadian time 6 (CT6) in the middle of the subjective day. The circadian oscillator in the system is temperature compensated. This original report reveals the relationship between electric discharge activity and the circadian pacemaker in Eigenmannia and provides an alternative system to investigate circadian rhythms in vertebrates.


Asunto(s)
Ritmo Circadiano/fisiología , Pez Eléctrico/fisiología , Animales , Electrofisiología , Ambiente Controlado , Fotoperiodo , Temperatura
15.
J Agric Food Chem ; 47(11): 4799-801, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10552892

RESUMEN

Samples of maize grown in various districts of Taiwan were collected and analyzed for the presence of fumonisin B(1) (FB(1)) and fumonisin B(2) (FB(2)) using high-performance liquid chromatography. Forty-nine (44.5%) and 2 (1.8%) of 110 samples were found to contain FB(1) (109-1148 ng/g) and FB(2) (222-255 ng/g), respectively. The frequency of detection and also the maximum FB(1) concentration were found in samples from Penton (2/2, 262 ng/g), followed by Chiayi (18/26, 264 ng/g), Tainan (8/16, 160 ng/g), Hualinen (5/14, 1148 ng/g), Taitung (7/20, 109 ng/g), and Yunlin (9/26, 361 ng/g). Of the 110 samples examined, only 2 samples from Hualinen had been detected containing FB(2). During an analysis of the distribution pattern of FB(1), it became apparent that >79% of tested samples had FB(1) concentrations <100 ng/g, whereas 2.7% (or 3 samples) contained FB(1) >300 ng/g. These results clearly illustrated that domestically produced maize for human consumption is frequently contaminated with FB(1).


Asunto(s)
Ácidos Carboxílicos/análisis , Carcinógenos Ambientales/análisis , Fumonisinas , Micotoxinas/análisis , Zea mays/química , Microbiología de Alimentos , Taiwán
16.
J Laryngol Otol ; 111(11): 1060-3, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9472577

RESUMEN

The usual method of reconstructing a hypopharyngeal defect during total laryngectomy includes pharyngeal muscle layer closure, which may result in high pharyngoesophageal pressure. We hypothesize that nonclosure of the pharyngeal muscle can reduce the pressure of the pharyngoesophageal segment which can reduce the chances of the formation of pharyngocutaneous fistulae. A technique of nonmuscular closure of a hypopharyngeal defect is presented. The differences in the rate of fistula formation and swallowing function between patients with usual and nonmuscular closure were also studied. Sixty consecutive laryngectomees were enrolled in this study. Thirty patients received usual closure after total laryngectomy, whereas the other 30 patients underwent non closure of their pharyngeal muscles. One patient (3.3 per cent) in the nonmuscular closure group and three patients (10 per cent) in the usual closure group developed a pharyngocutaneous fistula. The pharyngoesophageal pressures of the nonmuscular closure group were significantly lower than those of the usual closure group. We conclude that the technique of nonclosure of the pharyngeal constrictor muscle after total laryngectomy is relatively more simple and is not associated with a higher rate of fistula formation. Furthermore, nonclosure of the pharyngeal constrictor muscle is preferable to muscular closure because it reduces the spasm of the pharyngoesophageal segment which limits voice rehabilitation.


Asunto(s)
Neoplasias Laríngeas/cirugía , Laringectomía/métodos , Cirugía Plástica/métodos , Fístula Cutánea/etiología , Esófago/fisiopatología , Femenino , Fístula/etiología , Estudios de Seguimiento , Humanos , Neoplasias Laríngeas/fisiopatología , Laringectomía/efectos adversos , Masculino , Persona de Mediana Edad , Cuello , Enfermedades Faríngeas/etiología , Faringe/fisiopatología , Presión , Cirugía Plástica/efectos adversos
17.
Artículo en Inglés | MEDLINE | ID: mdl-9139363

RESUMEN

Owing to the limited value of phage typing to determine the epidemiological association of Salmonella typhi (S. typhi) strains isolated from the source of typhoid fever, we analyzed ribosomal RNA (rRNA) gene restriction patterns to differentiate the independently isolated strains of identical phage type. The data showed that the restriction patterns of PstI was most polymorphic among four enzymes (BamHI, EcoRI, PstI, and SmaI) used, which revealed 13 types among 25 strains belonged to 4 phage types, 1 untypable and 2 not-determined strains. Total 25 strains of S. typhi were divided into 15 combination types by the rRNA restriction patterns with three enzymes (BamHI, PstI, and SmaI).


Asunto(s)
Técnicas de Tipificación Bacteriana , ARN Bacteriano/análisis , ARN Ribosómico/análisis , Mapeo Restrictivo/métodos , Salmonella typhi/clasificación , Salmonella typhi/genética , Adolescente , Adulto , Anciano , Preescolar , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Longitud del Fragmento de Restricción , Taiwán/epidemiología , Fiebre Tifoidea/epidemiología , Fiebre Tifoidea/microbiología
18.
Aliment Pharmacol Ther ; 34(8): 994-1004, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21848629

RESUMEN

BACKGROUND: The diagnosis of gastro-oesophageal reflux disease (GERD) is based on reflux symptoms. Although metabolic syndrome has been linked to erosive oesophagitis (EO), the impact of insulin resistance, the core of the metabolic syndrome, on reflux symptoms remains to be elucidated. AIM: To assess the effects of insulin resistance on GERD, including both endoscopic findings and symptoms. METHODS: A total of 743 sonographic noncirrhotic adult subjects, who underwent an upper gastrointestinal endoscopic examination, completed a gastro-oesophageal reflux questionnaire and had available fasting insulin data were included. Endoscopic findings were classified according to the Los Angeles classification. Homeostatic model assessment-insulin resistance (HOMA-IR) index was used to evaluate the status of insulin resistance. Univariate and multivariate approaches were used to evaluate the associations between insulin resistance and GERD. RESULTS: Older age, male gender, smoking and alcohol consumption increased the prevalence of EO, but not GERD symptoms. A large waist circumference, high fasting blood glucose levels and high number of metabolic syndrome components were associated with increased prevalence of both EO and GERD symptoms, while high blood pressure was associated with increased prevalence of EO only. Moreover, higher scores in the gastro-oesophageal reflux questionnaire were associated with higher HOMA-IR index, and higher HOMA-IR index was associated with increased prevalence of EO (adjusted odds ratio 1.14, 95% CI 1.03-1.26, P = 0.012). CONCLUSIONS: Our findings demonstrate clear associations between insulin resistance, metabolic syndrome and GERD. Whether reducing insulin resistance may improve GERD symptoms or EO deserves prospective study.


Asunto(s)
Reflujo Gastroesofágico/fisiopatología , Resistencia a la Insulina/fisiología , Índice de Severidad de la Enfermedad , Adulto , Factores de Edad , Anciano , Índice de Masa Corporal , Estudios Transversales , Endoscopía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Prevalencia , Factores de Riesgo , Factores Sexuales , Encuestas y Cuestionarios , Taiwán/epidemiología , Ultrasonografía
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