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1.
Biochem J ; 477(1): 45-60, 2020 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-31820794

RESUMEN

Membrane-active peptides have been extensively studied to probe protein-membrane interactions, to act as antimicrobial agents and cell-penetrating peptides (CPPs) for the delivery of therapeutic agents to cells. Hundreds of membrane-active sequences acting as CPPs have now been described including bioportides that serve as single entity modifiers of cell physiology at the intracellular level. Translation of promising CPPs in pre-clinical studies have, however, been disappointing as only few identified delivery systems have progressed to clinical trials. To search for novel membrane-active peptides a sequence from the EGFR juxtamembrane region was identified (named EJP18), synthesised, and examined in its L- and D-form for its ability to mediate the delivery of a small fluorophore and whole proteins to cancer cell lines. Initial studies identified the peptide as being highly membrane-active causing extensive and rapid plasma membrane reorganisation, blebbing, and toxicity. At lower, non-toxic concentrations the peptides outperformed the well-characterised CPP octaarginine in cellular delivery capacity for a fluorophore or proteins that were associated with the peptide covalently or via ionic interactions. EJP18 thus represents a novel membrane-active peptide that may be used as a naturally derived model for biophysical protein-membrane interactions or for delivery of cargo into cells for therapeutic or diagnostic applications.


Asunto(s)
Péptidos de Penetración Celular/farmacología , Portadores de Fármacos/farmacología , Sistemas de Liberación de Medicamentos/métodos , Neoplasias/tratamiento farmacológico , Receptores ErbB/farmacología , Proteínas Fluorescentes Verdes/administración & dosificación , Células HeLa , Humanos , Células MCF-7 , Dominios Proteicos
2.
Int J Obes (Lond) ; 42(2): 231-243, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28630461

RESUMEN

BACKGROUND: Obesity is associated with gut microbiota dysbiosis, disrupted intestinal barrier and chronic inflammation. Given the high and increasing prevalence of obesity worldwide, anti-obesity treatments that are safe, effective and widely available would be beneficial. We examined whether the medicinal mushroom Antrodia cinnamomea may reduce obesity in mice fed with a high-fat diet (HFD). METHODS: Male C57BL/6J mice were fed a HFD for 8 weeks to induce obesity and chronic inflammation. The mice were treated with a water extract of A. cinnamomea (WEAC), and body weight, fat accumulation, inflammation markers, insulin sensitivity and the gut microbiota were monitored. RESULTS: After 8 weeks, the mean body weight of HFD-fed mice was 39.8±1.2 g compared with 35.8±1.3 g for the HFD+1% WEAC group, corresponding to a reduction of 4 g or 10% of body weight (P<0.0001). WEAC supplementation reduced fat accumulation and serum triglycerides in a statistically significant manner in HFD-fed mice. WEAC also reversed the effects of HFD on inflammation markers (interleukin-1ß, interleukin-6, tumor necrosis factor-α), insulin resistance and adipokine production (leptin and adiponectin). Notably, WEAC increased the expression of intestinal tight junctions (zonula occludens-1 and occludin) and antimicrobial proteins (Reg3g and lysozyme C) in the small intestine, leading to reduced blood endotoxemia. Finally, WEAC modulated the composition of the gut microbiota, reducing the Firmicutes/Bacteroidetes ratio and increasing the level of Akkermansia muciniphila and other bacterial species associated with anti-inflammatory properties. CONCLUSIONS: Supplementation with A. cinnamomea produces anti-obesogenic, anti-inflammatory and antidiabetic effects in HFD-fed mice by maintaining intestinal integrity and modulating the gut microbiota.


Asunto(s)
Antrodia/química , Dieta Alta en Grasa , Disbiosis/dietoterapia , Microbioma Gastrointestinal/efectos de los fármacos , Inflamación/dietoterapia , Obesidad/dietoterapia , Extractos Vegetales/farmacología , Plantas Medicinales/química , Animales , Modelos Animales de Enfermedad , Disbiosis/fisiopatología , Resistencia a la Insulina/fisiología , Masculino , Medicina Tradicional , Ratones , Ratones Endogámicos C57BL , Obesidad/fisiopatología
3.
J Nanosci Nanotechnol ; 18(10): 7281-7285, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29954574

RESUMEN

This paper analytically investigates the picosecond laser ablation of polymer. Laser-pulsed ablation is a well-established tool for polymer. However the ablation mechanism of laser processing for polymer has not been thoroughly understood yet. This study utilized a thermal transport model to analyze the relationship between the ablation rate and laser fluences. This model considered the energy balance at the decomposition interface as the ablation mechanisms and is applied to predict the laser-ablated depth of Acrylonitrile Butadiene Styrene/PolyVinyl Chloride (ABS/PVC). The calculated variation of the ablation rate with the logarithm of the laser fluence agrees with the measured data. The effects of material properties and processing parameters on the ablation depth per pulse are discussed for picosecond laser processing of ABS/PVC.

4.
BMC Cardiovasc Disord ; 17(1): 154, 2017 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-28610565

RESUMEN

BACKGROUND: Many studies have determined that dehydration is an independent predictor of outcome after ischemic stroke (IS); however, none have determined if the use of thrombolytic therapy modifies the negative impact of poor hydration. To inform the stroke registry established at our institution, we conducted a retrospective study to determine if dehydration remains a negative prognostic factor after IS patients treated with tissue plasminogen activator (tPA). METHODS: Between 2007 and 2012, we recruited 382 subjects; 346 had data available and were divided into 2 groups on the basis of their blood urea nitrogen/creatinine (BUN/Cr) ratio. Dehydrated subjects had a BUN/Cr ratio ≥ 15; hydrated subjects had a BUN/Cr < 15. The primary outcome was impairment at discharge as graded by the Barthel Index (BI) and the modified Rankin Scale (mRS). RESULTS: The dehydration group had a greater mean age; more women; lower mean levels of hemoglobin, triglycerides, and sodium; and higher mean potassium and glucose levels. A favorable outcome as assessed by the mRS (≤2) was significantly less frequent among dehydrated subjects, but a favorable outcome by the BI (≥60) was not. Logistic regression and multivariate models confirmed that dehydration is an independent predictor of poor outcome by both the mRS and the BI; however, it was not predictive when patients were stratified by Trial of Org 10,172 in Acute Stroke Treatment subtype. CONCLUSIONS: Our findings indicate that use of thrombolytic therapy does not eliminate the need to closely monitor hydration status in patients with IS.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Deshidratación/complicaciones , Fibrinolíticos/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Terapia Trombolítica/métodos , Activador de Tejido Plasminógeno/uso terapéutico , Equilibrio Hidroelectrolítico , Anciano , Biomarcadores/sangre , Nitrógeno de la Urea Sanguínea , Isquemia Encefálica/complicaciones , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/fisiopatología , Distribución de Chi-Cuadrado , Creatinina/sangre , Deshidratación/diagnóstico , Deshidratación/fisiopatología , Evaluación de la Discapacidad , Femenino , Fibrinolíticos/efectos adversos , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Sistema de Registros , Estudios Retrospectivos , Factores de Riesgo , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/fisiopatología , Terapia Trombolítica/efectos adversos , Factores de Tiempo , Activador de Tejido Plasminógeno/efectos adversos , Resultado del Tratamiento
5.
Eur J Neurol ; 23(3): 494-500, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26801969

RESUMEN

BACKGROUND AND PURPOSE: Recent large series studies have demonstrated that dehydration is common amongst stroke subjects and is associated with poor outcome. However, the effects of hydration status on the development of collaterals have never been discussed. In this study, the hypothesis that hydration status is an important factor for developing collaterals after acute middle cerebral artery (MCA) infarction was tested. METHODS: Eighty-seven patients with acute infarction due to occlusion of the MCA were enrolled. Two collateral markers, posterior cerebral artery (PCA) laterality and fluid-attenuated inversion recovery hyperintense vessels (HVs) were assessed from magnetic resonance imaging. Dehydration status was defined by a nitrogen to creatinine ratio ≧ of 15. The associations between dehydration status and the development of collaterals were estimated. RESULTS: Sixty-one of 87 patients (70.1%) were identified as dehydrated. The development of PCA laterality and HVs shows a significant difference between dehydrated and euhydrated patients. A serum nitrogen to creatinine ratio <15, diastolic blood pressure and the presence of a dense MCA on computed tomography were significantly associated with the development of PCA laterality. A serum nitrogen to creatinine ratio <15, the initial National Institutes of Health Stroke Scale score, the presence of a dense MCA and calcifications of the internal carotid artery on computed tomography were significantly associated with the development of HVs. Dehydration remained an independent negative predictor for the development of PCA laterality and HVs in the multivariate analysis. CONCLUSIONS: Hydration status is associated with the development of collateral flow after acute MCA occlusion. This preliminary study provides an imaging clue that hydration status and early hydration therapy could be important for acute stroke management.


Asunto(s)
Circulación Colateral/fisiología , Deshidratación/complicaciones , Infarto de la Arteria Cerebral Media/fisiopatología , Sistema de Registros , Anciano , Anciano de 80 o más Años , Deshidratación/sangre , Femenino , Humanos , Infarto de la Arteria Cerebral Media/terapia , Masculino , Persona de Mediana Edad , Arteria Cerebral Posterior/diagnóstico por imagen , Estudios Retrospectivos
6.
J Nanosci Nanotechnol ; 15(11): 9303-7, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26726687

RESUMEN

This paper investigates the thermal transport in hollow microscale and nanoscale spheres subject to electrical heat source using nontraditional thermal transport model. Working as supercapacitor electrodes, carbon hollow micrometer- and nanometer-sized spheres needs excellent heat transfer characteristics to maintain high specific capacitance, long cycle life, and high power density. In the nanoscale regime, the prediction of heat transfer from the traditional heat conduction equation based on Fourier's law deviates from the measured data. Consequently, the electrical heat source-induced heat transfer characteristics in hollow micrometer- and nanometer-sized spheres are studied using nontraditional thermal transport model. The effects of parameters on heat transfer in the hollow micrometer- and nanometer-sized spheres are discussed in this study. The results reveal that the heat transferred into the spherical interior, temperature and heat flux in the hollow sphere decrease with the increasing Knudsen number when the radius of sphere is comparable to the mean free path of heat carriers.


Asunto(s)
Carbono/química , Transferencia de Energía , Calor , Modelos Químicos , Nanosferas/química , Termodinámica , Carbono/efectos de la radiación , Simulación por Computador , Conductividad Eléctrica , Campos Electromagnéticos , Nanosferas/efectos de la radiación , Conductividad Térmica
7.
Int J Clin Pract ; 69(2): 228-34, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25363271

RESUMEN

PURPOSE: Whether patients with inflammatory bowel disease (IBD) exhibit a high risk of developing varicella zoster virus (VZV) infection in Asian populations remains inconclusive. We investigated the causal relationship between two diseases by analysing the Taiwan National Health Insurance Research Database. PATIENTS AND METHODS: Based on a universal insurance claims database, we enrolled 7055 IBD patients and 28,220 age- and sex-matched controls. We calculated the hazard ratios (HRs) and 95% confidence intervals (CIs) of the herpes zoster virus (HZV) in the IBD and comparison cohorts, using the Cox proportional hazards regression model. RESULTS: Patients with IBD exhibited significantly higher risk of the HZV compared with the controls (adjusted HRs, 1.42; 95% CI, 1.27-1.60). Further analysis indicated that male patients (adjusted HRs, 1.61; 95% CI, 1.35-1.92), aged 35-44 (adjusted HRs, 1.47; 95% CI, 1.08-2.01) and aged 65 years and older (adjusted HRs, 1.47; 95% CI, 1.19-1.80), and patients without comorbidities (adjusted HRs, 1.44; 95% CI, 1.26-1.66), exhibited excessive risks of VZV infection. Moreover, our findings show that the overall risk of developing VZV infection increased risk from 1.03 (95% CI, 0.90-1.18) (≤ 2 visits) to 9.76 (95% CI, 7.60-12.5) (> 4 visits), which correlates positively with the frequency of medical visits (trend test p < 0.0001). CONCLUSION: Patients with IBD, particularly men aged 35-44/65 years and over, and patients without comorbidities, are associated with a long-term risk of VZV infection. The excessive risk of VZV infection should be considered for administering vaccines to IBD patients.


Asunto(s)
Herpesvirus Humano 3 , Enfermedades Inflamatorias del Intestino/complicaciones , Adulto , Anciano , Pueblo Asiatico , Varicela/epidemiología , Estudios de Cohortes , Comorbilidad , Femenino , Herpes Zóster/epidemiología , Humanos , Enfermedades Inflamatorias del Intestino/epidemiología , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Factores de Riesgo , Taiwán/epidemiología
8.
J Nutr Health Aging ; 27(11): 940-945, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37997713

RESUMEN

OBJECTIVES: The main aim of this study was to examine the association of sarcopenia and subjective memory complaints with the incidence of dementia in a population-based cohort of cognitively unimpaired older adults. DESIGN: Three-year longitudinal study. SETTINGS AND PARTICIPANTS: A total of 2163 community-dwelling persons aged 65 years or older who participated in the National Health Interview Survey in Taiwan, 2017. MEASUREMENTS: Sarcopenia was determined based on SARC-F, a self-reported symptom-based questionnaire that includes five components: strength, assistance walking, rise from a chair, climb stairs, and falls. Two questions ("Do you have difficulties with your memory or attention?" and "Do you have difficulties with your memory only or attention only or both?") were used to screen for subjective memory complaints (SMCs). The incidence of dementia was determined by data linkage to the Taiwan National Health Insurance claims database from 2018 to 2020. RESULTS: Among the 2163 participants without dementia at baseline, 135 had incident dementia during the 3-year follow-up, giving a crude incidence rate of 6.2% (135/2163). Compared to participants free from sarcopenia and SMCs, the adjusted hazard ratio for incident dementia was 1.83 (95% confidence interval [CI]: 1.23-2.72) for SMCs alone, 2.40 (95% CI: 1.17-4.93) for sarcopenia alone, and 2.49 (95% CI: 1.21-5.11) for coexisting SMCs and sarcopenia. CONCLUSIONS: Our results indicate that sarcopenia screened with SARC-F and SMCs independently predict the cognitively unimpaired older adults at risk of incident dementia. Our findings highlight the importance of screening not only for cognitive but also muscle deficits to identify those at increased risk of incident dementia.


Asunto(s)
Demencia , Sarcopenia , Humanos , Anciano , Sarcopenia/complicaciones , Sarcopenia/epidemiología , Sarcopenia/diagnóstico , Estudios Longitudinales , Vida Independiente , Encuestas y Cuestionarios , Demencia/epidemiología , Demencia/etiología , Evaluación Geriátrica/métodos
9.
J Nanosci Nanotechnol ; 12(6): 5004-8, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22905567

RESUMEN

We have fabricated surface-enhanced Raman scattering (SERS) substrates based on arrays of silver nanoparticles grown on porous anodic alumina templates. Using this nanotechnology platform, label-free and high-speed detection of bacteria are achieved. SERS spectra of various bacteria including Staphylococcus Aureus (Gram-positive bacterium), Klebsiella Pneumoniae (Gram-negative bacterium), and Mycobacterium Smegmatis (Mycobacterium) were recorded. The highly reproducible SERS-based technological platform is capable of differentiating different kinds of bacteria by PCA, LDA, clustering analysis, and SVM methods, which provides promising opportunity for biosensing of clinical microbes.


Asunto(s)
Bacterias/aislamiento & purificación , Técnicas Biosensibles/instrumentación , Recuento de Colonia Microbiana/instrumentación , Nanoestructuras/química , Nanotecnología/instrumentación , Espectrometría Raman/instrumentación , Bacterias/química , Membrana Celular/química , Diseño de Equipo , Análisis de Falla de Equipo , Luz , Nanoestructuras/ultraestructura , Dispersión de Radiación
10.
Rev Sci Instrum ; 93(6): 063105, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35778029

RESUMEN

A hyperspectral imaging system (HIS) is a helpful tool that acquires spatial and spectral information from a target. This study developed a coaxial heterogeneous HIS (CHHIS) to collect spectral images with wavelengths ranging from 400 to 1700 nm. In this system, a visible (VIS) spectrometer and a short-wave infrared (SWIR) spectrometer are combined with a coaxial optical path to share the same field of view. This structure reduces the complexity of spatial registration and maintains the scanning duration of two spectrometers as that of a single spectrometer. The spectrometers are also replaceable for extending the detecting spectral range of the system. The calibration methodologies, including spatial correction, spectral calibration, and reflectance calibration, were developed for this system. The signal-to-noise ratio of VIS and SWIR spectrometers in the CHHIS was up to 40 and 60 dB when the exposure time of the VIS and SWIR imaging sensors was 1000 and 10 ms, respectively. When the target distance was at 600 mm, the spatial error of VIS and SWIR images in the scanning direction was less than 1 pixel; these results proved that the system was stable.


Asunto(s)
Diagnóstico por Imagen , Imágenes Hiperespectrales , Calibración
11.
J Neuroradiol ; 38(4): 242-5, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21257203

RESUMEN

Aneurysms arising from the lenticulostriate artery (LSA) are rare. So far, only 23 cases have been reported in the literature (Ahn et al. 2007 [1], Gandhi et al. 2008 [2], Harreld et al. 2010 [3]). Early detection and treatment of these aneurysms is difficult because of their small size, deep location and complex surrounding vasculature. The majority of reported cases were treated surgically, and only two were treated with endovascular embolization (Harreld et al. 2010 [3], Larrazabal et al. 2001 [4]). We present here a case of an LSA aneurysm that was successfully embolized with n-butyl cyanoacrylate (n-BCA) with no recurrence after 1 year of follow-up.


Asunto(s)
Aneurisma Roto/terapia , Enfermedad Cerebrovascular de los Ganglios Basales/terapia , Embolización Terapéutica/métodos , Enbucrilato/uso terapéutico , Aneurisma Intracraneal/terapia , Femenino , Humanos , Persona de Mediana Edad , Resultado del Tratamiento
12.
Ann Oncol ; 20(7): 1249-56, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19276396

RESUMEN

BACKGROUND: The study compared the efficacy of a first-line treatment with day 1 i.v. vinorelbine (NVBiv) and day 8 oral vinorelbine (NVBo) versus docetaxel (DCT) in a cisplatin-based combination in advanced non-small-cell lung cancer, in terms of time to treatment failure (TTF), overall response, progression-free survival (PFS), overall survival (OS), tolerance and quality of life (QoL). METHODS: Patients were randomly assigned to receive cisplatin 80 mg/m2 with NVBiv 30 mg/m2 on day 1 and NVBo 80 mg/m2 on day 8 every 3 weeks, after a first cycle of NVBiv 25 mg/m2 on day 1 and NVBo 60 mg/m2 on day 8 (arm A) or cisplatin 75 mg/m2 and DCT 75 mg/m2 on day 1 every 3 weeks (arm B), for a maximum of six cycles in both arms. RESULTS: From 2 February 2004 to 1 January 2006, 390 patients were entered in a randomised study and 381 were treated. The patient characteristics are as follows (arms A/B): metastatic (%) 80.5/84.8; patients with three or more organs involved (%) 45.3/40.8; median age 59.4/62.1 years; male 139/146; squamous (%) 34.2/33.5; adenocarcinoma (%) 41.6/39.3; median TTF (arms A/B in months) [95% confidence interval (CI)]: 3.2 (3.0-4.2), 4.1 (3.4-4.5) (P = 0.19); overall response (arms A/B) (95% CI): 27.4% (21.2% to 34.2%), 27.2% (21.0% to 34.2%); median PFS (arms A/B in months) (95% CI): 4.9 (4.4-5.9), 5.1 (4.3-6.1) (P = 0.99) and median OS (arms A/B in months) (95% CI): 9.9 (8.4-11.6), 9.8 (8.8-11.5) (P = 0.58). The median survival for squamous histology was 8.87/9.82 months and for adenocarcinoma 11.73/11.60 months for arms A and B, respectively. Main haematological toxicity was grade 3-4 neutropenia: 24.4% (arm A) and 28.8% (arm B). QoL as measured by the Lung Cancer Symptom Scale was similar in both arms. CONCLUSIONS: Both arms provided similar efficacy in terms of response, time-related parameters and QoL, with an acceptable tolerance profile. In the current Global Lung Oncology Branch trial 3, NVBo was shown to be effective as a substitute for the i.v. formulation. This can relieve the burden of the i.v. injection on day 8 and can optimise the hospital's resources and improve patient convenience.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Administración Oral , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Cisplatino/administración & dosificación , Terapia Combinada , Supervivencia sin Enfermedad , Docetaxel , Esquema de Medicación , Femenino , Estudios de Seguimiento , Humanos , Infusiones Intravenosas , Estimación de Kaplan-Meier , Masculino , Estudios Prospectivos , Calidad de Vida , Análisis de Supervivencia , Taxoides/administración & dosificación , Resultado del Tratamiento , Vinblastina/administración & dosificación , Vinblastina/análogos & derivados , Vinorelbina
13.
Lupus ; 18(14): 1246-51, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19880550

RESUMEN

XRCC1 plays a central role in mammalian DNA repair processes. Two polymorphisms of XRCC1, rs1799782 (Arg > Trp at codon 194) and rs25487 (Arg > Gln at codon 399), are common in the Han Chinese population. Our objective was to analyze the relationship between these two functional single-nucleotide polymorphisms (SNPs) and systemic lupus erythematosus (SLE) in the Taiwanese Han Chinese population. Genotyping was performed by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) on 172 SLE patients and 160 normal controls. Our data indicate that the frequency of A/G at codon 399 differed between patients and controls (p = 0.01; odds ratio: 1.80; 95% confidence interval: 1.17-2.75), but the allelic frequency analysis did not reveal significant differences. For the SNP at codon 194, there were no differences in either allelic or genotype frequencies between SLE patients and normal subjects. Clinical association studies of SLE symptoms revealed the involvement of the A/G polymorphism at codon 399 in SLE pathogenesis. Our results indicate that a functional SNP at codon 399 of XRCC1 is associated with the development of SLE.


Asunto(s)
Pueblo Asiatico/genética , Pueblo Asiatico/estadística & datos numéricos , Proteínas de Unión al ADN/genética , Lupus Eritematoso Sistémico/etnología , Lupus Eritematoso Sistémico/genética , Reparación del ADN/genética , Frecuencia de los Genes , Genotipo , Humanos , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo de Nucleótido Simple , Factores de Riesgo , Taiwán/epidemiología , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X
14.
Oncogene ; 25(14): 1991-2003, 2006 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-16301996

RESUMEN

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer deaths worldwide and is highly correlated with hepatitis virus infection. Our previous report shows that a DEAD box RNA helicase, DDX3, is targeted and regulated by hepatitis C virus (HCV) core protein, which implicates the involvement of DDX3 in HCV-related HCC development. In this study, the potential role of DDX3 in hepatocarcinogenesis is investigated by examining its expression in surgically excised human HCC specimens. Here we report the differential deregulation of DDX3 expression in hepatitis virus-associated HCC. A significant downregulation of DDX3 expression is found in HCCs from hepatitis B virus (HBV)-positive patients, but not from HCV-positive ones, compared to the corresponding nontumor tissues. The expression of DDX3 is differentially regulated by the gender and, moreover, there is a tendency that the downregulation of DDX3 expression in HCCs is more frequent in males than in females. Genetic knockdown of DDX3 with small interfering RNAs (siRNA) in a nontransformed mouse fibroblast cell line, NIH-3T3, results in a premature entry to S phase and an enhancement of cell growth. This enhanced cell cycle progression is linked to the upregulation of cyclin D1 and the downregulation of p21(WAF1) in the DDX3 knockdown cells. In addition, constitutive reduction of DDX3 expression increases the resistance of NIH-3T3 cells to serum depletion-induced apoptosis and enhances the ras-induced anchorage-independent growth, indicating the involvement of DDX3 in cell growth control. These findings together with the previous study suggest that the deregulation of DDX3, a DEAD box RNA helicase with cell growth-regulatory functions, is involved in HBV- and HCV-associated pathogenesis.


Asunto(s)
Carcinoma Hepatocelular/genética , División Celular/fisiología , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Hepacivirus/patogenicidad , Neoplasias Hepáticas/genética , ARN Helicasas/genética , Animales , Secuencia de Bases , Western Blotting , Carcinoma Hepatocelular/enzimología , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/virología , ARN Helicasas DEAD-box , Humanos , Neoplasias Hepáticas/enzimología , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/virología , Ratones , Datos de Secuencia Molecular , Células 3T3 NIH , ARN Helicasas/fisiología , ARN Interferente Pequeño/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia de Ácido Nucleico
15.
Radiat Prot Dosimetry ; 175(1): 87-95, 2017 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-27655802

RESUMEN

This paper presents improved and extended results of our previous study on corrections for conventional neutron dose meters used in environments with high-energy neutrons (En > 10 MeV). Conventional moderated-type neutron dose meters tend to underestimate the dose contribution of high-energy neutrons because of the opposite trends of dose conversion coefficients and detection efficiencies as the neutron energy increases. A practical correction scheme was proposed based on analysis of hundreds of neutron spectra in the IAEA-TRS-403 report. By comparing 252Cf-calibrated dose responses with reference values derived from fluence-to-dose conversion coefficients, this study provides recommendations for neutron field characterization and the corresponding dose correction factors. Further sensitivity studies confirm the appropriateness of the proposed scheme and indicate that (1) the spectral correction factors are nearly independent of the selection of three commonly used calibration sources: 252Cf, 241Am-Be and 239Pu-Be; (2) the derived correction factors for Bonner spheres of various sizes (6"-9") are similar in trend and (3) practical high-energy neutron indexes based on measurements can be established to facilitate the application of these correction factors in workplaces.


Asunto(s)
Neutrones , Dosis de Radiación , Calibración , Radiometría , Valores de Referencia , Encuestas y Cuestionarios
16.
AJNR Am J Neuroradiol ; 38(5): 1061-1067, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28385881

RESUMEN

BACKGROUND AND PURPOSE: CSF hypovolemia is a core feature of spontaneous intracranial hypotension. Spontaneous intracranial hypotension is characterized by orthostatic headache and radiologic manifestations, including CSF along the neural sleeves, diffuse pachymeningeal enhancement, and/or venous engorgement. However, these characteristics are only qualitative. Quantifying intraspinal CSF volumes could improve spontaneous intracranial hypotension diagnosis and evaluation of hypovolemic statuses in patients with spontaneous intracranial hypotension. The purpose of this study was to compare intraspinal CSF volumes across spontaneous intracranial hypotension stages and to test the clinical applicability of these measures. MATERIALS AND METHODS: A cohort of 23 patients with spontaneous intracranial hypotension and 32 healthy controls was subjected to brain MR imaging and MR myelography with 1.5T imaging. An automatic threshold-based segmentation method was used to calculate intraspinal CSF volumes at initial hospitalization (spontaneous intracranial hypotension-initial), partial improvement (spontaneous intracranial hypotension-intermediate), and complete recovery (spontaneous intracranial hypotension-recovery) stages. RESULTS: The mean intraspinal CSF volumes observed were the following: 95.31 mL for healthy controls, 72.31 mL for spontaneous intracranial hypotension-initial, 81.15 mL for spontaneous intracranial hypotension-intermediate, and 93.74 mL for spontaneous intracranial hypotension-recovery. Increased intraspinal CSF volumes were related to disease recovery (P < .001). The intraspinal CSF volumes of patients before complete recovery were significantly lower than those of healthy controls. With the estimated intradural CSF volumes as a reference, the intraspinal CSF volume percentage was lower in patients with spontaneous intracranial hypotension with venous engorgement than in those without it (P = .058). CONCLUSIONS: With a threshold-based segmentation method, we found that spinal CSF hypovolemia is fundamentally related to spontaneous intracranial hypotension. Intraspinal CSF volumes could be a sensitive parameter for the evaluation of treatment response and follow-up monitoring in patients with spontaneous intracranial hypotension.


Asunto(s)
Hipotensión Intracraneal/líquido cefalorraquídeo , Hipotensión Intracraneal/diagnóstico , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Mielografía/métodos
17.
Artículo en Inglés | MEDLINE | ID: mdl-16439187

RESUMEN

Six fishermen were victims (including one death) of food poisoning from unknown fish on their boat in central Taiwan Strait, in April 2001. The symptoms were like those of tetrodotoxin (TTX) poisoning. As there was no remaining fish, a new protocol was developed to determine TTX in the urine and blood of the victims. The urine and blood samples were cleansed using a C18 Sep-Pak cartridge column, and the toxin was extracted by methanol. The eluate was filtered through a microcentrifuge filter. The filtrate was freeze-dried, dissolved in distilled water, and determined by LC-MS. The recovery was more than 88.9%. The detection limit was 15.6 nM. A linear relationship between response and concentration was obtained between 93.75 and 9375 nM of TTX. It was shown that the urine and blood of the victims contained TTX. The range of TTX was 4.5-40.6 nM in blood and 47-344 nM in urine. Judging from the symptoms of the victims and the experimental data, the causative agent of the food poisoning was identified as TTX.


Asunto(s)
Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Tetrodotoxina/sangre , Tetrodotoxina/orina , Ultrafiltración/métodos , Adulto , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Tetrodotoxina/envenenamiento
18.
Transplant Proc ; 48(2): 507-11, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27109988

RESUMEN

BACKGROUND: Intestinal stem cells (ISCs) are responsible for the regeneration of intestinal epithelium. In a previous study, we demonstrated that sodium selenite is 1 of the key factors that enhances the growth of ISCs in crypt culture medium. The goal of the present article was to investigate the effect of selenite on the proliferative and antioxidative activities of ISCs. MATERIALS AND METHODS: Five-week old BALB/C mice were administered phosphate-buffered saline or sodium selenite (4 mg/kg/d) for 7 days before ISCs were harvested. The proliferative activity of ISC was indexed by the growth of crypt organoids. The messenger RNA expression levels of ISC markers were quantified by using real-time polymerase chain reaction. The activity of antioxidative enzymes was assayed for glutathione peroxidase (GPx), thioredoxin reductase (TrxR), and superoxide dismutase. RESULTS: Treatment with sodium selenite induced a 1.88-fold increase in the growth number of organoids from ISCs, with elevated expression of leucine-rich repeat-containing G-protein-coupled receptor 5, B lymphoma Moloney murine leukemia virus insertion region homolog-1, and Musashi-1, compared with the ISCs from control samples treated with phosphate-buffered saline. The antioxidative activity of GPx and TrxR was significantly enhanced in the selenite-treated groups (1.55- and 1.23-fold increases, respectively). CONCLUSIONS: Selenite positively regulated the proliferation of ISCs and activated the expression of ISC markers. The elevated activity of GPx and TrxR induced by selenite should promote the antioxidative ability of ISCs and benefit the growth of organoids.


Asunto(s)
Mucosa Intestinal/efectos de los fármacos , Organoides/efectos de los fármacos , Ácido Selenioso/farmacología , Células Madre/efectos de los fármacos , Oligoelementos/farmacología , Animales , Proliferación Celular/efectos de los fármacos , Mucosa Intestinal/patología , Ratones , Ratones Endogámicos BALB C , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores Acoplados a Proteínas G/biosíntesis , Células Madre/citología
19.
J Orthop Res ; 23(2): 446-53, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15734261

RESUMEN

Chondrogenic differentiation by mesenchymal progenitor cells (MPCs) is associated with cytokines such as transforming growth factor-beta 1 (TGF-beta1) and dexamethasone. Extracellular matrix (ECM) also regulates the differentiation by MPCs. To define whether ECM plays a functional role in regulation of the chondrogenic differentiation by MPCs, an in vitro model was used. That model exposed to dexamethasone, recombinant human TGF-beta1(rhTGF-beta1) and collagens. The results showed that MPCs incorporated with dexamethasone and rhTGF-beta1 increased proliferation and expression of glycosaminoglycan (GAG) after 14 days. Type II collagen enhanced the GAG synthesis, but did not increase alkaline phosphatase (ALP) activity. When adding dexamethasone and rhTGF-beta1 MPCs increased mRNA expression of Sox9. Incorporation with type II collagen, dexamethasone and rhTGF-beta1, MPCs induced mRNA expression of aggrecan and enhanced levels of type II collagen, and Sox9 mRNA. In contrast, incorporation with type I collagen, dexamethasone and rhTGF-beta1 MPCs reduced levels of aggrecan, and Sox9 mRNA, and showed no type II collagen mRNA. Altogether, these results indicate that type I and II collagen, in addition to the cytokine effect, may play a functional role in regulating of chondrogenic differentiation by MPCs.


Asunto(s)
Condrocitos/efectos de los fármacos , Colágeno Tipo II/farmacología , Colágeno Tipo I/farmacología , Células Madre Mesenquimatosas/fisiología , Agrecanos , Animales , Diferenciación Celular/efectos de los fármacos , Condrocitos/citología , Dexametasona/farmacología , Proteínas de la Matriz Extracelular/genética , Glicosaminoglicanos/biosíntesis , Humanos , Lectinas Tipo C , Proteoglicanos/genética , ARN Mensajero/análisis , Conejos , Factor de Crecimiento Transformador beta/farmacología , Factor de Crecimiento Transformador beta1
20.
Int J Oral Maxillofac Surg ; 34(3): 311-20, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15741041

RESUMEN

The aim of this study was to design a biodegradable implant, in the form of a reconstituted collagen template in order to promote and support regeneration of the temporomandibular joint disc. Bovine collagen (Major Type I) was pepsinized, reduced by beta-mercaptoethanol, and reconstituted by glutaraldehyde. The reconstitution of the collagen increased the resistance to biological degradation by collagenase, optimized the pore size and possessed maximum biological activity for tissue regeneration. Forty-four New Zealand rabbits underwent either sham surgical procedures or partial temporomandibular joint discectomy. In animals that underwent partial discectomy, the discs were replaced by either reconstituted collagen templates or subdermal grafts. Some of the surgerized animals did not receive any type of implant or disc substitute. Gross and histological examination of the surgerized temporomandibular joints was carried out at 1-, 2-, and 3-month intervals after surgery on the selected groups of animals. Marked arthritic changes were observed after 3 months in the partially discectomized joints without implantation. In contrast, the discs, which received a reconstituted collagen template or subdermal graft exhibited regeneration and nearly normal morpology. No foreign body response was observed in experimental groups 3 months after implantation. This study demonstrated that the reconstituted collagen did as well as subdermal grafts in supporting and facilitating regeneration of the disc and the former was found to have some advantages over the latter.


Asunto(s)
Implantes Absorbibles , Regeneración Ósea/efectos de los fármacos , Colágeno Tipo I/farmacología , Disco de la Articulación Temporomandibular/efectos de los fármacos , Animales , Trasplante Óseo , Bovinos , Reacción a Cuerpo Extraño , Masculino , Conejos , Disco de la Articulación Temporomandibular/fisiología , Disco de la Articulación Temporomandibular/cirugía
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