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1.
Chem Sci ; 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39345769

RESUMEN

Electrochemical binders used to immobilize electrocatalysts on electrodes are essential in all fields of electrochemistry. However, conventional organic-based binders like Nafion generally suffer from oxidative decomposition at high potentials on anodic electrodes and have high charge transport resistivity. This work proposes the use of acidic redox-assisted deposition to form cobalt manganese oxyhydroxides (CMOH) as a solid-state inorganic binder. CMOH remains stable under high oxidative currents and ensures catalyst adhesion even under significant peel-off stress as shown by experiments involving the alkaline oxygen evolution reaction (OER) using RuO2 as a catalyst immobilized on a rotating disc electrode. While the molecular structure of Nafion decays significantly after 45 minutes under OER conditions at 3.86 V, the CMOH binder is able to support the powder catalysts (RuO2 and NiO x ) showing stability around 1000 mA cm-2 without significant current decay over 24 hours. The robust catalyst adhesion is a result of the formation of chemical bonds between the electrode and the binder and it can be further improved by increasing the applied loading of CMOH. Unlike Nafion, both the OER activity and the diffusion kinetics are not significantly affected by the CMOH binder. It has also been shown that using CMOH as a binder leads to lower charge transfer resistances R ct and higher electrochemical surface areas compared to systems using Nafion. This is partially due to the presence of metal sites in different oxidation states which has been shown to increase intrinsic conductivity, facilitating the charge hopping at the binder/electrocatalyst interface. With this, the present work provides a proof-of-concept for inorganic metal oxides as promising solid-state binders for a wide range of applications in electrochemistry, demonstrating CMOH's outstanding characteristic of strong adhesion to support other highly active but adhesion-weak electrocatalysts.

2.
BMC Infect Dis ; 22(1): 427, 2022 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-35509007

RESUMEN

BACKGROUND: Measles vaccination was introduced in Taiwan in 1978, and the disease was declared eliminated in Taiwan in 2007. However, new cases have been reported unpredictably since then. Hospital medical staff are at particularly high risk for measles. We evaluated the immunity status of hospital medical staff after changes in national and local hospital vaccination policies. METHODS: This retrospective study was conducted in a tertiary care medical center from January 2008 to June 2018. Data were retrieved from all healthcare workers receiving employment medical examinations. Those with a full medical record including the geometrical mean titer (GMT) of anti-measles IgG were included. Age and sex differences in the GMT were analyzed by Student's t-tests and Chi-squared tests. Univariate and multivariate logistic regression analysis were used to determine the odds of immunity. RESULTS: The IgG positive rate increased with age group (p < 0.001). Seropositive rates for the birth before 1977 and after 1978 groups were 94.8% and 70.2% (p < 0.001). The odds ratio was also significantly different between both cohorts (1.000 vs. 0.423, p = 0.002). Staff in the examination department showed the lowest positive percentage of 70.3% (95% CI: 66.9-73.7%), whereas staff in preventive and long-term care services disclosed the highest positive percentage of 83.2% (95% CI: 76.1-90.2%). Subgroups 2015, 2017, and 2018 (p = 0.046, 0.046, 0.049), after the vaccination booster policy was launched, showed significant increases in seropositivity. CONCLUSIONS: Immunity efficacy is better in birth groups before 1977, which was highly related to natural infection before national policy launched. The policy of vaccination is an effective method, but medical staff attains inadequate protective antibody levels for maintenance of herd immunity. A pre-employment policy of screening a third booster vaccine of measles (or MMR) is recommended to lower the incidence of disease spreading and avoid outbreaks.


Asunto(s)
Sarampión , Anticuerpos Antivirales , Femenino , Humanos , Inmunoglobulina G , Masculino , Sarampión/epidemiología , Sarampión/prevención & control , Vacuna Antisarampión , Vacuna contra el Sarampión-Parotiditis-Rubéola , Cuerpo Médico , Políticas , Estudios Retrospectivos , Estudios Seroepidemiológicos , Centros de Atención Terciaria , Vacunación
3.
Angew Chem Int Ed Engl ; 61(23): e202200535, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-35304808

RESUMEN

New preparation methods of vectors are the key to developing the next generation of biomacromolecule delivery systems. In this study, a controllable disulfide exchange polymerization was established to obtain low-toxicity and efficient bioreducible polyguanidines (mPEG225 -b-PSSn , n=13, 26, 39, 75, 105) by regulating the concentration of activated nucleophiles and reaction time under mild reaction conditions. The relationship between the degrees of polymerization and biocompatibility was studied to identify the optimal polyguanidine mPEG225 -b-PSS26 . Such polyguanidine exhibited good in vitro performance in delivering different functional nucleic acids. The impressive therapeutic effects of mPEG225 -b-PSS26 were further verified in the 4T1 tumor-bearing mice as well as the mice with full-thickness skin defects. Controllable disulfide exchange polymerization provides an attractive strategy for the construction of new biomacromolecule delivery systems.


Asunto(s)
Neoplasias , Ácidos Nucleicos , Animales , Disulfuros , Ratones , Polimerizacion , Compuestos de Sulfhidrilo
4.
Environ Sci Pollut Res Int ; 29(26): 39610-39621, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35107729

RESUMEN

In this study, the effect of a bio-based environment-friendly surfactant, cardanol polyoxyethylene ether (BGF), on the wettability of the surface of low-rank coal (LRC) and its mechanism were studied. The adsorption experiment showed that the adsorption of the surfactant conformed to the Langmuir adsorption model and the pseudo-second-order kinetic model. The adsorption was mainly affected by hydrogen bonding, and the adsorption rate was affected by intraparticle diffusion and liquid film diffusion. The wettability experiment showed that the influence of BGF on the wettability of the surface of LRC followed the given order: BGF-7 > BGF-10 > BGF-15. The investigation of adhesion work showed that the adhesion work and the stability of the coal-water system decreased after adsorption. Fourier transform infrared and X-ray photoelectron spectroscopy analyses showed that after adsorption, the peak strength of vinyl ether, the content of elemental carbon, and the content of C-C/C-H groups increased.


Asunto(s)
Carbón Mineral , Contaminantes Químicos del Agua , Adsorción , Carbón Mineral/análisis , Concentración de Iones de Hidrógeno , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Tensoactivos , Contaminantes Químicos del Agua/análisis , Humectabilidad
5.
Mol Biol Rep ; 49(4): 2973-2983, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35000049

RESUMEN

BACKGROUND: Autophagy dysregulation and oxidative stress play critical pathophysiological roles in developing obesity-related metabolic health disorders. This study aims to investigate how autophagy modulation is related to resveratrol (RSV) antioxidant activities and preventive effects on steroidogenesis decline associated with a high-fat diet (HFD) and oxidative damage. METHODS AND RESULTS: Eight-week-old C57BL/6 J male mice were fed with HFD with or without supplement RSV (400 mg/kg/day) by gavage for 16 weeks. The control group was fed with a standard diet with no RSV or the same amount of RSV. Mouse Leydig cell line TM3 cell was used for in vitro studies. Oxidative stress was induced in TM3 cells with H2O2, followed by RSV treatment plus autophagy activator rapamycin or autophagy inhibitor 3-methyladenine, respectively. RSV supplement could upregulate proteins level of StAR and mitochondrial proteins COX4 and mtTFA, indicating the amelioration of steroidogenesis decline and mitochondrial dysfunction caused by HFD. Antioxidants such as GPx4 and SOD2 were improved by RSV as well. The observation of autophagosomes and the changes in expressions of LC3II/I, Beclin1, and Atg7 indicated that RSV could reverse the autophagy defect associated with HFD. 3-methyladenine inhibition of autophagy partially abolished RSV protection on mitochondrial function and steroidogenesis in H2O2-challenged TM3 cells. However, the combination use of rapamycin and RSV did not improve protection on Leydig cells against oxidative damage. CONCLUSIONS: The stimulation of autophagy by RSV is closely linked to its antioxidant actions and positive impact on steroidogenesis in HFD mice. The findings suggest RSV is protective against obesity-related Leydig cell impairment.


Asunto(s)
Dieta Alta en Grasa , Peróxido de Hidrógeno , Animales , Autofagia , Dieta Alta en Grasa/efectos adversos , Peróxido de Hidrógeno/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Estrés Oxidativo , Resveratrol/farmacología
6.
Cell Death Discov ; 8(1): 40, 2022 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-35091534

RESUMEN

Sepsis-induced cardiac dysfunction can lead to death in sepsis. In this case, we targeted to explore in detail the relative mechanism of microRNA (miR)-124-3p in sepsis-induced myocardial injury via the specific protein 1/histone deacetylase 4/hypoxia-inducing factor 1α (SP1/HDAC4/HIF-1α) axis. Septic rats were modeled by cecal ligation puncture while in vitro septic cardiomyocyte H9C2 were induced by lipopolysaccharide (LPS). miR-124-3p/SP1/HDAC4/HIF-1α expression levels in myocardial tissues of septic rats and LPS-treated H9C2 cells were measured. miR-124-3p overexpression and SP1 silencing assays were implemented on LPS-treated H9C2 cells to explore theirs actions in inflammation, oxidative stress and cell apoptosis. The interactions of miR-124-3p, SP1, and HDAC4 were testified. miR-124-3p was lowly expressed while SP1, HDAC4, and HIF-1α were highly expressed in sepsis. Upregulation of miR-124-3p ameliorated inflammation, oxidative stress, and apoptosis of LPS-treated H9C2 cells. Silencing SP1 improved LPS-induced damage to cardiomyocytes. miR-124-3p targeted SP1 and HDAC4 interacted with SP1. SP1 overexpression antagonized miR-124-3p upregulation-induced improvements in LPS-induced cardiomyocyte damage. This study illustrates that miR-124-3p improves myocardial injury in septic rats through targeted regulation of SP1 to mediate HDAC4/HIF-1α.

7.
Front Mol Biosci ; 8: 743417, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34912844

RESUMEN

Circular RNAs (circRNAs) are usually enriched in neural tissues, yet about 80% circRNAs have lower expression in gliomas relative to normal brains, highlighting the importance of circRNAs as tumor suppressors. However, the clinical impact as well as the pathways regulated by the tumor-suppressive circRNAs remain largely unknown in glioblastoma (GBM). Through bioinformatic analysis followed by experimental validation, we found that hsa_circ_0114014 (circLRRC7) was dramatically down-regulated in GBM when compared with normal brain tissues (p < 0.0001). GBM patients with a lower circLRRC7 expression had poorer progression-free survival (PFS, p < 0.05) and overall survival (OS, p < 0.05). Analyses of the predicted target miRNAs of circLRRC7 in CSCD and CRI databases, in combination with the miRNA expression data in GBMs and normal brains from GSE database, revealed miR-1281 as a potential downstream target of circLRRC7. Subsequently, the target genes of hsa-mir-1281 were predicted by TargetScan, miRDB and miRNATAR databases. Intersection analysis and correlation test indicated that PDXP was a potential target of miR-1281. In summary, circLRRC7 may be a tumor suppressor that associated with miR-1281 and PDXP expression in GBM, which may provide novel therapeutic targets for GBM treatment.

8.
Pathol Oncol Res ; 27: 1609844, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34483751

RESUMEN

Vasculogenic mimicry (VM) has been identified as an important vasculogenic mechanism in malignant tumors, but little is known about its clinical meanings and mechanisms in oligodendroglioma. In this study, VM-positive cases were detected in 28 (20.6%) out of 136 oligodendroglioma samples, significantly associated with higher WHO grade, lower Karnofsky performance status (KPS) scores, and recurrent tumor (p < 0.001, p = 0.040, and p = 0.020 respectively). Patients with VM-positive oligodendroglioma had a shorter progress-free survival (PFS) compared with those with VM-negative tumor (p < 0.001), whereas no significant difference was detected in overall survival (OS) between these patients. High levels of phosphorylate serine/threonine kinases Ataxia-telangiectasia mutated (pATM) and phosphorylate Ataxia-telangiectasia and Rad3-Related (pATR) were detected in 31 (22.8%) and 34 (25.0%), respectively out of 136 oligodendroglioma samples. Higher expressions of pATM and pATR were both associated with a shorter PFS (p < 0.001 and p < 0.001). VM-positive oligodendroglioma specimens tended to exhibit higher pATM and pATR staining than VM-negative specimens (rs = 0.435, p < 0.001 and rs = 0.317, p < 0.001). Besides, Hypoxia-inducible factor-1α (HIF1α) expression was detected in 14(10.3%) samples, correlated with higher WHO grade and non-frontal lobe (p = 0.010 and p = 0.029). However, no obvious connection was detected between HIF1α expression and VM formation (p = 0.537). Finally, either univariate or multivariate analysis suggested that VM was an independent unfavorable predictor for oligodendroglioma patients (p < 0.001, HR = 7.928, 95%CI: 3.382-18.584, and p = 0.007, HR = 4.534, 95%CI: 1.504-13.675, respectively). VM is a potential prognosticator for tumor progression in oligodendroglioma patients. Phosphorylation of ATM and ATR linked to treatment-resistance may be associated with VM formation. The role of VM in tumor progression and the implication of pATM/pATR in VM formation may provide potential therapeutic targets for oligodendroglioma treatment.


Asunto(s)
Neovascularización Patológica/patología , Oligodendroglioma/patología , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Progresión de la Enfermedad , Femenino , Humanos , Estado de Ejecución de Karnofsky , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Recurrencia Local de Neoplasia , Neovascularización Patológica/metabolismo , Oligodendroglioma/irrigación sanguínea , Oligodendroglioma/metabolismo , Fosforilación , Pronóstico , Supervivencia sin Progresión
9.
Environ Sci Pollut Res Int ; 28(41): 58629-58639, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34118002

RESUMEN

The large-scale application of ionic surfactants in industrial and agricultural production has caused great harm to the environment due to by-products. In order to remove this pollutant from the environment, graphene oxide as an adsorption material has received extensive attention. However, practically, it is difficult to separate the GO from aqueous solutions, making water treatment on a large scale challenging. To allow the recycling of GO, as well as enhance its adsorption ability to remove surfactants from water, a composite of magnetic graphene oxide (MGO) and 1-dodecyl-3-methylimidazolium chloride ionic liquid (IL) was synthesized. The MGO was prepared by coprecipitation, and IL-MGO was prepared by ultrasonic impregnation. Nitrogen adsorption-desorption curves show that the specific surface area of the composite was increased by the addition of the IL, from 103.28 to 163.35 m2/g. Finally, the adsorption ability of MGO and IL-MGO for the nonionic surfactant NP10EO was investigated. The results showed that the adsorption of MGO on NP10EO fits the Langmuir isothermal model and the quasi-second-order kinetic model. In addition, the equilibrium adsorption capacity of NP10EO by MGO at 298K, 308K, and 318K can reach 87.03 mg/g, 156.25 mg/g, and 214.13 mg/g. The adsorption is an endothermic reaction that occurs spontaneously and is governed by physical adsorption. The adsorption of IL-MGO on NP10EO conforms to the Langmuir isotherm model and the quasi-second-order kinetic model. At 298K, 308K, and 318K, the equilibrium adsorption capacity of NP10EO by MGO reached 261.02 mg/g, 280.24 mg/g, and 295.03 mg/g, respectively. Compared with the two results, the incorporation of IL greatly improved the adsorption capacity of MGO to NP10EO.


Asunto(s)
Grafito , Líquidos Iónicos , Contaminantes Químicos del Agua , Adsorción , Cinética , Fenómenos Magnéticos , Tensoactivos , Contaminantes Químicos del Agua/análisis
10.
BMJ Open ; 6(6): e010973, 2016 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-27279477

RESUMEN

OBJECTIVES: To investigate the association between the trends of CT utilisation in an emergency department (ED) and changes in clinical imaging practice and patients' disposition. SETTING: A hospital-based retrospective observational study of a public 1520-bed referral medical centre in Taiwan. PARTICIPANTS: Adult ED visits (aged ≥18 years) during 2009-2013, with or without receiving CT, were enrolled as the study participants. MAIN OUTCOME MEASURES: For all enrolled ED visits, we retrospectively analysed: (1) demographic characteristics, (2) triage categories, (3) whether CT was performed and the type of CT scan, (4) further ED disposition, (5) ED cost and (6) ED length of stay. RESULTS: In all, 269 239 adult ED visits (148 613 male patients and 120 626 female patients) were collected during the 5-year study period, comprising 38 609 CT scans. CT utilisation increased from 11.10% in 2009 to 17.70% in 2013 (trend test, p<0.001). Four in 5 types of CT scan (head, chest, abdomen and miscellaneous) were increasingly utilised during the study period. Also, CT was increasingly ordered annually in all age groups. Although ED CT utilisation rates increased markedly, the annual ED visits did not actually increase. Moreover, the subsequent admission rate, after receiving ED CT, declined (59.9% in 2009 to 48.2% in 2013). CONCLUSIONS: ED CT utilisation rates increased significantly during 2009-2013. Emergency physicians may be using CT for non-emergent studies in the ED. Further investigation is needed to determine whether increasing CT utilisation is efficient and cost-effective.


Asunto(s)
Servicio de Urgencia en Hospital/organización & administración , Tomografía Computarizada por Rayos X/estadística & datos numéricos , Tomografía Computarizada por Rayos X/tendencias , Triaje/clasificación , Adolescente , Adulto , Anciano , Análisis Costo-Beneficio , Bases de Datos Factuales , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Derivación y Consulta , Estudios Retrospectivos , Taiwán , Adulto Joven
11.
Medicine (Baltimore) ; 94(50): e2279, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26683955

RESUMEN

To investigate the association between iodinated contrast medium (ICM) exposure during computed tomography (CT) and the subsequent development of thyroid disorders in patients without known thyroid disease in Taiwan, an iodine-sufficient area. We conducted a population-based cohort study by using data from 1996 to 2012 in the Taiwan National Health Insurance Research Database. A total of 33,426 patients who underwent ICM-enhanced CT were included as the study cohort. To avoid selection bias, we used propensity score and matched for the index year (defined as the year of first ICM exposure) to retrieve 33,426 patients as the comparison cohort. No patients in the 2 cohorts had any known thyroid disease before the index year. Patients with a history of amiodarone treatment or coronary angiography and those with <1 year follow-up were excluded. Participants were followed until a new diagnosis of thyroid disorder or December 31, 2011. Hazard ratios (HRs) with 95% confidence interval (95% CI) were calculated using the Cox proportional hazards regression. An association was identified between ICM exposure and the subsequent development of thyroid disorders after adjustment for potential confounders (adjusted HR = 1.17; 95% CI: 1.07-1.29; P = 0.001). Male patients and patients' ages ≥40 years in the ICM-exposure cohort had a higher adjusted HR for developing thyroid disorders than did those in the non-ICM-exposure cohort. Hypothyroidism had the highest adjusted HR (HR = 1.37; 95% CI: 1.06-1.78; P < 0.05) among all thyroid disorders and had a higher risk of development or detection during >0.5-year post-ICM exposure compared with that during ≤0.5-year post-ICM exposure (HR = 1.26; 95% CI: 1.01-1.58; P < 0.05). Repeated ICM exposure increased the risk of thyroid disorders in patients who accepted >1 time of ICM per year on average compared with those who accepted ≤1 time per year on average (adjusted HR = 3.04; 95% CI: 2.47-3.73; P < 0.001). This study identified ICM exposure during CT as a risk factor for the subsequent development of thyroid disorders in patients without known thyroid disease, particularly in patients with repeated exposure.


Asunto(s)
Medios de Contraste/efectos adversos , Compuestos de Yodo/efectos adversos , Enfermedades de la Tiroides/epidemiología , Tomografía Computarizada por Rayos X , Adulto , Anciano , Bases de Datos Factuales , Femenino , Estudios de Seguimiento , Humanos , Seguro de Salud , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Puntaje de Propensión , Taiwán/epidemiología
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