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1.
J Biol Regul Homeost Agents ; 27(2): 319-27, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23830383

RESUMEN

Previous experiments demonstrated that transgenic mice carrying both amyloid precursor protein and mutant ATP7B transgenes reduce amyloid plaques and diminish plasma Abeta levels. These experiments showed that a structural change of ATP7B may affect Alzheimer’s disease (AD) susceptibility. In this study three missense SNPs in ATP7B gene (rs1801243, rs1801244, and rs1801249) were chosen to test whether they were associated with AD. We tested this hypothesis using a case control design. The experimental data showed that there was a significant deviation from Hardy-Weinberg equilibrium (HWE) for SNP rs1801249 (c.3419 T greater than C, Val1140Ala) in the case group (p = 0.014) but not in the control group and that there was an association between SNP rs1801249 and AD under a recessive model (p = 0.003). The data also showed that the genotype frequency distribution of the ATP7B c.1366 G greater than C polymorphism (rs1801244, Val456Leu) differed significantly between the AD patients and the normal subjects (p = 0.012). In addition, the frequency of the TGC haplotype of SNPs rs1801243, rs1801244, and rs1801249 was significantly higher in the AD patients compared with the normal subjects (p = 8.49×10-7). These observations suggested that genetic variations in the copper transporter gene ATP7B might contribute to AD pathogenesis in the Taiwanese population.


Asunto(s)
Adenosina Trifosfatasas/genética , Enfermedad de Alzheimer/genética , Pueblo Asiatico/genética , Proteínas de Transporte de Catión/genética , Polimorfismo de Nucleótido Simple , Enfermedad de Alzheimer/etiología , ATPasas Transportadoras de Cobre , Variación Genética , Genotipo , Humanos
2.
Scand J Rheumatol ; 41(1): 44-9, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22150162

RESUMEN

OBJECTIVES: Systemic sclerosis (SSc) has been associated with high cancer risk. We compared the cancer risk among SSc patients with that among the general Taiwanese population. METHODS: The catastrophic illness registry of the Taiwan National Health Insurance Research Dataset (NHIRD) was used to identify patients diagnosed with SSc and cancer in Taiwan during 1996-2008. The standardized incidence ratio (SIR) for cancer was calculated, and mortality was ascertained using the data from the National Death Registry. RESULTS: Data analysis revealed that 2053 (472 men, 1581 women) Taiwanese individuals were diagnosed with SSc during the study period and 83 (30 men, 53 women) had cancer. The incidence of cancer was 6.9/1000 person-years. The most common cancer sites in male SSc patients were the lung (n = 10), oral cavity and pharynx (n = 8), and gastrointestinal tract (n = 4), and those in female patients were the breast (n = 11), lungs (n = 11), and blood (n = 6). Compared to the Taiwanese population of 1996, the all-cancer SIR for SSc was 1.63 [95% confidence interval (CI) 1.31-2.01]. Cancer risk was elevated for cancers of the lung (SIR 4.20), oral cavity and pharynx (SIR 3.67), and blood (SIR 3.50). A cancer diagnosis in SSc patients was associated with a hazard ratio (HR) of 2.15 (95% CI 1.30-3.53). Among cancer patients, a diagnosis of SSc was not associated with increased mortality. CONCLUSIONS: SSc patients are at high risk of developing cancer, especially of the lung, oral cavity and pharynx, and blood.


Asunto(s)
Neoplasias/epidemiología , Esclerodermia Sistémica/epidemiología , Adulto , Femenino , Neoplasias Hematológicas/epidemiología , Humanos , Incidencia , Neoplasias Pulmonares/epidemiología , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/epidemiología , Neoplasias Faríngeas/epidemiología , Sistema de Registros , Factores de Riesgo , Taiwán/epidemiología
3.
Br J Dermatol ; 165(6): 1273-9, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21895620

RESUMEN

BACKGROUND: Nationwide data on the epidemiology of dermatomyositis (DM) and polymyositis (PM) were limited. OBJECTIVES: This study was to estimate the incidence, occurrence of cancer and mortality of DM and PM in Taiwan. METHODS: Both the register of critical illness of the Taiwan National Health Insurance Research Dataset and the National Death Registry of Taiwan were used to calculate estimates of the incidence, cancer association, and mortality of DM and PM between 2003 and 2007. RESULTS: A total of 803 DM and 500 PM cases were identified between 2003 and 2007. Mean age at diagnosis was 44·0 ± 18·3 years for DM and 49·2 ± 15·9 years for PM. The overall annual incidences of DM and PM were 7·1 (95% CI 6·6-7·6) and 4·4 (95% CI 4·0-4·8) cases per million population. The incidence of both DM and PM increased with age and reached a peak at age 50-59 years. One hundred and eleven (13·8%) patients with DM and 31 (6·2%) patients with PM had cancers. The diagnosis of most cancers was made after the diagnoses of DM (n = 71; 64·0%) and PM (n = 21; 67·7%). Overall, the standardized incidence ratios (SIR) for cancer were 5·36 (4·12-6·87) and 1·80 (1·10-2·79) among patients with DM and PM; however, during the first year, SIRs for cancer were 24·55 (95% CI 18·62-31·79) and 9·17 (95% CI 14·82-15·93) in patients with DM and PM, respectively. The most common types of cancer were nasopharyngeal cancer for men and breast cancer for women. Patients with DM and PM had standardized mortality ratios of 7·68 (6·41-9·01) and 5·29 (4·28-6·48). CONCLUSION: This study reports robust estimates of important aspects of the epidemiology of both DM and PM in Taiwan. This highlights the rarity of these diseases, and their associated cancer risks and increased mortality.


Asunto(s)
Dermatomiositis/epidemiología , Neoplasias/mortalidad , Polimiositis/mortalidad , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Incidencia , Lactante , Masculino , Persona de Mediana Edad , Sistema de Registros , Factores de Riesgo , Taiwán/epidemiología , Adulto Joven
4.
Br J Dermatol ; 161(2): 273-80, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19438447

RESUMEN

BACKGROUND: The treatment of vitiligo remains a challenge for clinical dermatologists. We have previously shown that the helium-neon laser (He-Ne laser, 632.8 nm) is a therapeutic option for treatment of this depigmentary disorder. OBJECTIVES: Addressing the intricate interactions between melanocytes, the most important cellular component in the repigmentation scheme of vitiligo, and their innate extracellular matrix collagen type IV, the current study aimed to elucidate the effects of the He-Ne laser on melanocytes. METHODS: Cultured melanocytes were irradiated with the He-Ne laser. Relevant biological parameters including cell attachment, locomotion and growth were evaluated. In addition, the potentially involved molecular pathways were also determined. RESULTS: Our results show that in addition to suppressing mobility but increasing attachment to type IV collagen, the He-Ne laser stimulates melanocyte proliferation through enhanced alpha2beta1 integrin expression. The expression of phosphorylated cyclic-AMP response element binding protein (CREB), an important regulator of melanocyte growth, was also upregulated by He-Ne laser treatment. Using a specific mitochondrial uncoupling agent [carbonyl cyanide m-chlorophenyl-hydrazone (CCCP)], the proliferative effect of the He-Ne laser on melanocytes was abolished and suppression of melanocyte growth was noted. CONCLUSIONS: In summary, we have demonstrated that the He-Ne laser imparts a growth stimulatory effect on functional melanocytes via mitochondria-related pathways and proposed that other minor pathways including DNA damage may also be inflicted by laser treatment on irradiated cells. More importantly, we have completed the repigmentation scheme of vitiligo brought about by He-Ne laser light in vitro and provided a solid theoretical basis regarding how the He-Ne laser induces recovery of vitiligo in vivo.


Asunto(s)
Colágeno Tipo IV/efectos de la radiación , Expresión Génica/efectos de la radiación , Láseres de Gas , Terapia por Luz de Baja Intensidad , Melanocitos/efectos de la radiación , Vitíligo/radioterapia , Adulto , Western Blotting , Adhesión Celular , Proliferación Celular , Colágeno Tipo IV/metabolismo , Humanos , Melanocitos/metabolismo , Neón , Vitíligo/genética , Vitíligo/metabolismo
5.
Rev Port Pneumol (2006) ; 22(5): 262-5, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27118611

RESUMEN

PURPOSE: To determine the likelihood that clinicians know carbon dioxide levels before administering supplemental oxygen to patients with neuromuscular disorders, to quantitate the effect of oxygen therapy on carbon dioxide retention, and to explore hypercapnia contributing to the need to intubate and use of continuous noninvasive ventilatory support to avert it. BASIC PROCEDURES: A retrospective chart review for patients with neuromuscular disorders intubated or having intubation averted by using continuous noninvasive ventilatory support with carbon dioxide known pre- and during oxygen administration. MAIN FINDINGS: For only 2 of 316 patients who were intubated did clinicians know carbon dioxide levels prior to administering oxygen. For four cases, intubation was averted by continuous noninvasive ventilatory support and mechanical insufflation-exsufflation despite severe hypercapnia and acidosis. After initiating oxygen therapy, patients' carbon dioxide partial pressures increased 52.1±42.0mmHg in over as little as 20min. PRINCIPAL CONCLUSIONS: Clinicians should attempt to use continuous noninvasive ventilatory support and mechanical insufflation-exsufflation rather than supplemental oxygen to normalize blood gases for neuromuscular ventilatory failure and should be prepared to intubate hypercapnic patients for whom oxygen is administered.


Asunto(s)
Hipercapnia/inducido químicamente , Terapia por Inhalación de Oxígeno/efectos adversos , Insuficiencia Respiratoria/terapia , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Hipercapnia/prevención & control , Lactante , Masculino , Persona de Mediana Edad , Enfermedades Neuromusculares/complicaciones , Insuficiencia Respiratoria/etiología , Estudios Retrospectivos
6.
Biochim Biophys Acta ; 1209(1): 130-9, 1994 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-7947975

RESUMEN

Human prostaglandin G/H synthase 1 and 2 were expressed in the baculovirus expression system and purified to high levels. Both enzymes were glycosylated. PGHS-1 appeared to be homogeneous by SDS-PAGE analysis but two closely migrating bands were detected in PGHS-2 preparation which were evidently due to heterogeneity in glycosylation. The amino-acid sequence of the N-termini of both isoforms indicated that the signal sequences were efficiently cleaved by the insect cells. The recombinant human PGHS-1 and PGHS-2 possessed both cyclooxygenase and peroxidase activities. Both had high affinities for arachidonate as substrate and underwent self-inactivation during catalysis. The recombinant isoforms were not pharmacologically identical, since some NSAIDs were selective inhibitors of either PGHS-1 or PGHS-2. This is the first report of high levels of expression and purification of human PGHS isoforms. The recombinant enzymes are invaluable in developing potent PGHS-2 selective inhibitors that may be efficacious anti-inflammatory drugs with no or low levels of toxicity.


Asunto(s)
Isoenzimas/genética , Prostaglandina-Endoperóxido Sintasas/genética , Secuencia de Aminoácidos , Animales , Antiinflamatorios no Esteroideos/farmacología , Ácido Araquidónico/metabolismo , Baculoviridae , Secuencia de Bases , Línea Celular , Clonación Molecular , Inhibidores de la Ciclooxigenasa/farmacología , Cartilla de ADN , Glicosilación , Humanos , Isoenzimas/antagonistas & inhibidores , Isoenzimas/aislamiento & purificación , Isoenzimas/metabolismo , Datos de Secuencia Molecular , Prostaglandina-Endoperóxido Sintasas/aislamiento & purificación , Prostaglandina-Endoperóxido Sintasas/metabolismo , Proteínas Recombinantes/antagonistas & inhibidores , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Spodoptera
7.
Biochem Pharmacol ; 50(4): 529-44, 1995 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-7646560

RESUMEN

Agents that inhibit hepatic cholesterol biosynthesis reduce circulating cholesterol levels in experimental animals and humans, and may be of pharmacological importance in the prevention of atherosclerosis. Azalanstat (RS-21607), a synthetic imidazole, has been shown to inhibit cholesterol synthesis in HepG2 cells, human fibroblasts, hamster hepatocytes and hamster liver, by inhibiting the cytochrome P450 enzyme lanosterol 14 alpha-demethylase. When administered orally to hamsters fed regular chow, RS-21607 (50 mg/kg/day) lowered serum cholesterol in a dose-dependent manner (ED50 = 62 mg/kg) in a period of 1 week. It preferentially lowered low density lipoprotein (LDL) cholesterol and apo B relative to high density lipoprotein (HDL) cholesterol and apo A-1. It also lowered plasma cholesterol levels in hamsters fed a high saturated fat and cholesterol diet. RS-21607 inhibited hepatic microsomal hydroxymethylglutaryl-CoA (HMG-CoA) reductase activity in hamsters in a dose-dependent manner (ED50 = 31 mg/kg), and this was highly correlated with serum cholesterol lowering (r = 0.97). Cholesterol lowering by azalanstat and cholestyramine was additive, and the increase in HMG-CoA reductase brought about by cholestyramine was attenuated significantly by azalanstat. In vitro studies with HepG2 cells indicated that this modulation of reductase activity was indirect, occurring at a post-transcriptional step, and it is proposed that a regulatory oxysterol derived from dihydrolanosterol (or lanosterol) may be responsible for this regulation. Azalanstat does not appear to lower circulating cholesterol in the hamster by up-regulation of the hepatic LDL receptor, suggesting that other mechanisms are involved. Orally administered azalanstat (50-75 mg/kg) stimulated hepatic microsomal cholesterol 7 alpha-hydroxylase activity by 50-400% in hamsters, and it is postulated that this may result from modified cholesterol absorption and bile acid synthesis.


Asunto(s)
Compuestos de Anilina/farmacología , Anticolesterolemiantes/farmacología , Colesterol/biosíntesis , Inhibidores Enzimáticos del Citocromo P-450 , Microsomas Hepáticos/metabolismo , Oxidorreductasas/antagonistas & inhibidores , Sulfuros/farmacología , Acetatos/metabolismo , Animales , Apolipoproteínas B/sangre , Línea Celular , Colesterol/sangre , Cricetinae , Grasas de la Dieta/administración & dosificación , Humanos , Hidroximetilglutaril-CoA Reductasas/metabolismo , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Lipoproteínas HDL/sangre , Lipoproteínas LDL/sangre , Lovastatina/farmacología , Masculino , Mesocricetus , Ácido Mevalónico/metabolismo , Microsomas Hepáticos/efectos de los fármacos , ARN Mensajero/análisis , Receptores de LDL/metabolismo , Esterol 14-Desmetilasa
8.
Vet Microbiol ; 71(1-2): 9-25, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10665530

RESUMEN

To verify the role of porcine reproductive and respiratory syndrome virus (PRRSV) infection on pulmonary defense mechanisms, alterations in the viability, morphology, and various functions of porcine alveolar macrophages (AMs) were evaluated in vitro for 2-72 h after exposure to a Taiwan isolate, tw91, at a multiplicity of infection (MOI) of 0.1. A low but constant rate of infection, around 5%, was seen in AMs from the PRRSV-infected group throughout the study. When compared with a mock-infected group, AMs from the PRRSV-infected group had a significantly lower viability at 18-72 h post-infection (HPI) as determined by trypan blue dye exclusion. Also during this time period, the cells showed morphological changes, including rounding, bleb formation, and rupture. The phagocytic and microbicidal capacity of AMs against Candida albicans was significantly inhibited after 6 HPI. Although the total amount of superoxide anion (O2-) and hydrogen peroxide (H2O2) produced by the AMs was reduced after 18 and 12 HPI, respectively, the amount of production was enhanced in both reactive oxygen species on a per viable cell basis after 12 HPI. In contrast, the level of bioactive tumor necrosis factor alpha (TNF-alpha) secretion, either total or on a per viable cell basis, was markedly reduced soon after PRRSV infection, up to 36 HPI, followed by a rebound thereafter. Prostaglandin E2 (PGE2) production was enhanced, both in total and on a per viable cell basis, in the first 6 h of infection, especially at 2 HPI. However, it became lower than that of the control after 36 HPI. The results indicated that PRRSV infection could cause, directly and/or indirectly, not only death of AMs but also adverse alterations in their morphology and function, although some of the effects seemed to be reversible. Because AMs are crucial to the host against airborne pathogens, PRRSV infection may potentially predispose pigs to secondary pulmonary infections.


Asunto(s)
Macrófagos Alveolares/virología , Síndrome Respiratorio y de la Reproducción Porcina/patología , Virus del Síndrome Respiratorio y Reproductivo Porcino/patogenicidad , Animales , Antígenos Virales/análisis , Células Cultivadas , Dinoprostona/metabolismo , Femenino , Peróxido de Hidrógeno/metabolismo , Masculino , Microscopía Electrónica de Rastreo/veterinaria , Fagocitosis , Organismos Libres de Patógenos Específicos , Superóxidos , Porcinos , Factor de Necrosis Tumoral alfa/metabolismo
9.
J Vet Diagn Invest ; 13(6): 534-7, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11724148

RESUMEN

A 14-year-old male Chapman's zebra had been treated for a cervical granulomatous cellulitis for 3 months prior to sudden death associated with myocardial fibrosis. Incidental findings at necropsy included multiple 3-8-cm unilocular cysts in the liver and lungs. Cysts contained either a clear fluid with or without hydatid sand or a gelatinous substance with foci of mineralization. Light and scanning electron microscopic examination of the hydatid sand revealed free protoscolices as well as intact and ruptured brood capsules with protoscolices attached to the germinal membrane. The protoscolices had 2 rows of 36-38 rostellar hooks with a length of 25-30 microm. The cyst wall consisted of inner germinal, intermediate laminated, and outer adventitial layers. Hydatidosis caused by Echinococcus granulosus was diagnosed based on the unilocular cysts, multiple protoscolices formed in a brood capsule, typical trilayered cyst wall, and herbivorous intermediate host. This is the first reported case of animal hydatidosis in Taiwan. The infection is thought to have been established 12 years ago in South Africa prior to importation.


Asunto(s)
Equinococosis Hepática/veterinaria , Equinococosis Pulmonar/veterinaria , Echinococcus/aislamiento & purificación , Equidae/parasitología , Animales , Autopsia/veterinaria , Equinococosis Hepática/patología , Equinococosis Pulmonar/patología , Echinococcus/patogenicidad , Resultado Fatal , Fibrosis/veterinaria , Masculino , Miocardio/patología , Taiwán
10.
Chemosphere ; 50(8): 1095-105, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12531717

RESUMEN

A batch system was applied to study the adsorption of reactive dye (reactive red 189) from aqueous solutions by cross-linked chitosan beads. The ionic cross-linking reagent sodium tripolyphosphate was used to obtain more rigid chitosan beads. To stabilize chitosan in acid solutions, chemical cross-linking reagent epichlorohydrin (ECH), glutaraldehyde and ethylene glycol diglycidyl ether was used and ECH shows a higher adsorption capacity. The Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms at different particle sizes and isotherm constants were determined. The Langmuir model agrees very well with experimental data and its calculated maximum monolayer adsorption capacity has very large value of 1802-1840 (g/kg) at pH 3.0, 30 degrees C. The kinetics of the adsorption with respect to the initial dye concentration, temperature, pH, ionic strength, and wet/dry beads were investigated. The pseudo-first-order, second-order kinetic models and intraparticle diffusion model were used to describe the kinetic data and the rate constants were evaluated. The dynamical data fit well with the second-order kinetic model, except for the dry beads fitting better with the first-order model. The adsorption capacity increases largely with decreasing solution pH or with increasing initial dye concentration. Thermodynamic parameters such as change in free energy (deltaG(0)), enthalpy (deltaH(0)), entropy (deltaS(0)) and activation energy were also determined. The adsorption mechanism is shown to be the electrostatic interactions between the dye and chitosan beads. The desorption data shows that the removal percent of dye RR 189 from the cross-linked chitosan beads is 63% in NaOH solutions at pH 10.0, 30 degrees C. The desorbed chitosan beads can be reused to adsorb the dye and to reach the same capacity as that before desorption.


Asunto(s)
Quelantes/química , Quitina/análogos & derivados , Quitina/química , Colorantes/química , Modelos Teóricos , Naftalenosulfonatos/química , Triazinas/química , Purificación del Agua/métodos , Adsorción , Quitosano , Difusión , Concentración de Iones de Hidrógeno , Temperatura , Industria Textil
11.
Appl Biochem Biotechnol ; 111(3): 139-52, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14665734

RESUMEN

Mushroom tyrosinase was immobilized on modified polystyrene- polyamino styrene (PSNH) and polymethylchloride styrene (PSCL)-to produce L-DOPA from L-tyrosine. Glutaraldehyde was used as an activating agent for the PSNH to immobilize the tyrosinase, and 10% (w/v) glutaraldehyde was optimal in conferring the highest specific activity (11.96 U/g) to the PSNH. Methylchloride on the PSCL was directly linked with the tyrosinase, and 1.5 mmol of Cl/g was optimal in attaining the specific activity of 17.0 U/g. The temperature and optimal acidity were, respectively, 60 degrees C and pH 5.5 for the PSNH, and 70 degrees C and pH 3.0 for the PSCL. In a 50-mL batch reactor working over 36 h, the L-DOPA production rate at 30 degrees C was 1.44 mg/(L x h) for the PSNH and 2.33 mg/(L x h) for the PSCL. The production rate over 36 h was 3.86 mg/(L x h) for the PSNH at 60 degrees C and 5.54 mg/(L x h) for the PSCL at 70 degrees C. Both of the immobilized enzymes showed a remarkable stability with almost no change in activity after being stored wet. The operational stability study indicated a 22.4% reduction in L-DOPA production for the PSNH and an 8.63% reduction for the PSCL over seven runs (each run was for 144 h at 30 degrees C) when the immobilized enzymes were used under turnover conditions. The immobilized tyrosinase was more stable on the PSCL than on the PSNH.


Asunto(s)
Enzimas Inmovilizadas/metabolismo , Levodopa/biosíntesis , Monofenol Monooxigenasa/metabolismo , Poliestirenos/química , Agaricales , Estabilidad de Enzimas , Enzimas Inmovilizadas/química , Glutaral/farmacología , Concentración de Iones de Hidrógeno , Cloruro de Metilo/química , Monofenol Monooxigenasa/química , Tamaño de la Partícula , Temperatura
12.
Aliment Pharmacol Ther ; 38(4): 432-9, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23799975

RESUMEN

BACKGROUND: Considerable evidence suggests that aspirin has a chemopreventive effect on colorectal cancer (CRC). However, optimal dose and treatment duration have not been defined, and data on the effects of low-dose aspirin are contradictory. AIM: To determine if the incidence of CRC in patients with low-dose aspirin use was lower than in those without aspirin use. METHOD: From Taiwan's National Health Insurance research database, aspirin users (n = 1985) were defined as adults (age ≥20 years) with at least 3.5 years of regular low-dose aspirin use (50-150 mg per day) between 1998 and 2002. Non-users (n = 7940) were those who did not use aspirin and were matched 4:1 with the user group by age, gender, date of ambulatory care (index date), and presence of known risk factors for cardiovascular disease (including hypertension, diabetes mellitus and hyperlipidaemia). Follow-up of the two study groups was made until the end of 2010, and incidences and hazard ratios of colorectal cancer were determined. RESULTS: During a median follow-up period of 8.9 years, 129 non-users and 14 users developed CRC, corresponding to incidence rates of 180.43 and 79.42 per 100,000 person-years respectively. Duration of aspirin use among users ranged from 3.5 to 12.6 years (mean 8.7 years). The multivariate-adjusted hazard ratio for CRC was 0.5 (95% confidence interval 0.28-0.87) among users as compared with non-users. CONCLUSIONS: Long-term use of low-dose aspirin appears to be associated with a lower incidence of CRC in patients with high cardiovascular risk. Further randomised clinical trials are necessary to confirm these findings.


Asunto(s)
Antiinflamatorios no Esteroideos/administración & dosificación , Aspirina/administración & dosificación , Enfermedades Cardiovasculares/tratamiento farmacológico , Neoplasias Colorrectales/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Antiinflamatorios no Esteroideos/farmacología , Aspirina/farmacología , Estudios de Cohortes , Neoplasias Colorrectales/prevención & control , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Factores de Riesgo , Taiwán , Factores de Tiempo , Adulto Joven
16.
Br J Dermatol ; 153(3): 498-505, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16120133

RESUMEN

BACKGROUND: Vitiligo is an acquired pigmentary disorder characterized by depigmentation of skin and hair. As the pathogenesis of this disease is still obscure, the treatment of vitiligo has generally been unsatisfactory and often disappointing. Topical tacrolimus (FK506) ointment has recently been added to the armamentarium against this pigmentary disorder. Despite its clinical efficacy, the underlying mechanisms of how topical tacrolimus induces repigmentation in vitiligo have rarely been investigated. As tacrolimus ointment is applied directly to the skin, its impact on keratinocytes (KCs) requires thorough investigation. OBJECTIVES: To investigate the effects of FK506 on melanocyte (MC) and melanoblast (MB) growth via KCs. METHODS: Cultured MCs and MBs were treated with supernatant of KC cultures conditioned with various concentrations of FK506. The impact of supernatant on MCs and MBs was assessed in terms of its effect on MC/MB proliferation, melanin formation and cell migration. The activities of matrix metalloproteinase (MMP)-2 and MMP-9, known for their influence on cell migration, were evaluated. The concentrations of MC/MB growth factors in the KC supernatant were also determined. RESULTS: Results demonstrated that proliferation of both MCs and MBs was significantly enhanced by FK506-treated KC supernatant. In addition, the concentration of stem cell factor in KC supernatant increased dose-dependently with FK506 treatment. The supernatant from FK506-treated KC culture showed a significant increase in MMP-9 activity. CONCLUSIONS: Our study provides in vitro evidence demonstrating that direct interaction between FK506 and KCs creates a favourable milieu for MC growth and migration. Furthermore, our findings provide a possible mechanism explaining how tacrolimus ointment induces repigmentation in patients with vitiligo.


Asunto(s)
Inmunosupresores/farmacología , Melanocitos/patología , Tacrolimus/farmacología , Vitíligo/tratamiento farmacológico , Adulto , Movimiento Celular , Proliferación Celular/efectos de los fármacos , Técnicas de Cocultivo , Medios de Cultivo Condicionados , Relación Dosis-Respuesta a Droga , Sustancias de Crecimiento/metabolismo , Humanos , Inmunosupresores/uso terapéutico , Queratinocitos/efectos de los fármacos , Queratinocitos/patología , Masculino , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Melaninas/metabolismo , Melanocitos/efectos de los fármacos , Melanocitos/metabolismo , Pomadas , Factor de Células Madre/farmacología , Estimulación Química , Tacrolimus/uso terapéutico , Vitíligo/metabolismo , Vitíligo/patología
17.
Proc Natl Sci Counc Repub China B ; 13(4): 250-7, 1989 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2517764

RESUMEN

Urease with a purity meeting the requirements of analytical use was purified from jack bean meal through steps consisting of 20% acetone extraction, heat treatment, acid precipitation, and lyophilization. For extraction of urease, one part of bean meal was mixed with 5 parts of 20% acetone containing 1 mM EDTA and 1 mM 2-mercaptoethanol, and stirred at 20 degrees C for 5 min. Milky substances in the extract were removed by heat treatment. Urease in the clear yellow supernatant was precipitated by adjusting the pH of the solution to 5.4 with citric acid. The acid precipitated urease was neutralized by dissolving in 0.015 M phosphate buffer, pH 8.5 (final pH 6.8 to 7.0) and then lyophilized. By this procedure, the purity of the enzyme was increase 14.7 fold, the recovery of activity was 63%, and the yield was 6.75 g from 1 kg of bean seeds. The specific activity of the preparation was 411 units/mg protein (240 units/mg solid), and the free ammonia content was less than 0.01 microgram per unit. Some other proteins were present in the urease preparation as examined by gel filtration and gradient polyacrylamide gel electrophoresis. The molecular weight of the enzyme estimated by gel filtration was 480,000. However, two urease activity bands with molecular weight of 230,000 and 480,000 were observed in the polyacrylamide gel electrophoregram. From the result of determination of blood urea nitrogen (BUN), this simple purification procedure could be used for practical preparation of urease from jack bean meal for clinical analysis.


Asunto(s)
Plantas/enzimología , Ureasa/aislamiento & purificación , Acetona , Nitrógeno de la Urea Sanguínea , Precipitación Química , Cromatografía en Gel , Ácido Edético , Fabaceae , Liofilización , Calor , Humanos , Concentración de Iones de Hidrógeno , Mercaptoetanol , Peso Molecular , Plantas Medicinales
18.
Curr Microbiol ; 39(2): 79-84, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10398831

RESUMEN

A new methanogenic isolate, designated as strain N2M9705 (=OCM 668), was isolated from an aquaculture fishpond near Wang-gong, Taiwan. This strain grew on trimethylamine and methanol, but it did not catabolize H2-CO2, acetate, or formate. The cells were stained Gram-negative, nonmotile, irregular coccus 0.6-0.8 micrometer in diameter. Gas vacuoles were observed and cell aggregated to form various sizes of granules. Cells grew optimally at 32 degrees -37 degrees C with 1% NaCl. The pH range of growth was 6.2-7.4, and higher pH inhibited the cell growth. The cells grew well in minimal medium, but growth was greatly stimulated by yeast extract and peptone. A comparison of 16S rDNA sequences of this organism phylogenetically related to Methanosarcina mazei. This is the first report of methyltrophic methanogenic isolated from an aquaculture fishpond.


Asunto(s)
Acuicultura , Methanosarcina/clasificación , Methanosarcina/aislamiento & purificación , Microbiología del Agua , Animales , Medios de Cultivo , ADN de Archaea/genética , ADN Ribosómico/genética , Peces/fisiología , Methanosarcina/citología , Methanosarcina/fisiología , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
19.
Curr Microbiol ; 41(1): 15-20, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10919393

RESUMEN

A new methanogenic isolate, designated as strain O1M9704 (=OCM 667), was isolated from the sediment of the estuarine environment in Eriln Shi, Taiwan. This strain grew on trimethylamine and methanol, but it did not catabolize H2-CO2, acetate, or formate. Cells grew optimally at 37 degrees C with 0.5% NaCl in neutral pH. The cells were stained Gram-negative, nonmotile, irregular coccus 0.3-0.6 microm in diameter. A comparison of 16S rDNA sequences phylogenetically related strain O1M9704 to Methanosarcina mazei. Gas vacuoles were observed both under phase contrast microscope and in thin sections in the electron microscope. Negative stain of electron micrographs showed a novel character of strain O1M9704. with tubule structure extended out of the cells. The tubule structure and gas vacuoles may benefit the adaptation of methanoarchaea in estuarine environment.


Asunto(s)
Methanosarcina/aislamiento & purificación , Microbiología del Agua , Medios de Cultivo , Methanosarcina/clasificación , Methanosarcina/fisiología , Microscopía Electrónica , Datos de Secuencia Molecular , Filogenia
20.
Proc Natl Sci Counc Repub China B ; 25(3): 193-6, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11480776

RESUMEN

A 10-year-old male aardwolf (Proteles cristatus) was presented abdominal distention and emaciation for 3 months. Physical examination revealed firm abdominal masses with effusions. Cytologic assessment of the effusion showed uniform round tumor cells with a surface brush border. Necropsy showed white velvety masses covering the peritoneal surface of the liver, gall bladder, stomach, omentum, mesentery, spleen, intestine, abdominal wall and diaphragm. Histologic examination demonstrated papillary projections, lined with cuboidal tumor cells supported by fibrous connective tissue cores, arising from the serosa of visceral organs. Cytoplasmic vacuolation and a surface brush border were evident on some cells under light microscopy. Tumor cells stained positive for both cytokeratin (AE1/AE3) and vimentin. Electron microscopy showed prominent surface microvilli, rough endoplasmic reticulum, mitochondria and desmosomes in tumor cells. This may be the first reported case of peritoneal mesothelioma in a captive wild aardwolf.


Asunto(s)
Animales de Zoológico , Carnívoros , Mesotelioma/veterinaria , Neoplasias Peritoneales/veterinaria , Animales , Ascitis/etiología , Biomarcadores de Tumor/análisis , Queratinas/análisis , Masculino , Mesotelioma/química , Mesotelioma/complicaciones , Mesotelioma/diagnóstico , Mesotelioma/patología , Proteínas de Neoplasias/análisis , Células Madre Neoplásicas/química , Células Madre Neoplásicas/ultraestructura , Neoplasias Peritoneales/química , Neoplasias Peritoneales/complicaciones , Neoplasias Peritoneales/diagnóstico , Neoplasias Peritoneales/patología , Vimentina/análisis
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