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1.
Molecules ; 27(9)2022 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-35566202

RESUMEN

A small fenbufen library comprising 18 compounds was prepared via Suzuki Miyara coupling. The five-step preparations deliver 9-17% biphenyl compounds in total yield. These fenbufen analogs exert insignificant activity against the IL-1 release as well as inhibiting cyclooxygenase 2 considerably. Both the para-amino and para-hydroxy mono substituents display the most substantial COX-2 inhibition, particularly the latter one showing a comparable activity as celecoxib. The most COX-2 selective and bioactive disubstituted compound encompasses one electron-withdrawing methyl and one electron-donating fluoro groups in one arene. COX-2 is selective but not COX-2 to bioactive compounds that contain both two electron-withdrawing groups; disubstituted analogs with both resonance-formable electron-donating dihydroxy groups display high COX-2 activity but inferior COX-2 selectivity. In silico simulation and modeling for three COX-2 active-p-fluoro, p-hydroxy and p-amino-fenbufens show a preferable docking to COX-2 than COX-1. The most stabilization by the p-hydroxy fenbufen with COX-2 predicted by theoretical simulation is consistent with its prominent COX-2 inhibition resulting from experiments.


Asunto(s)
Inhibidores de la Ciclooxigenasa 2 , Diseño de Fármacos , Antiinflamatorios/farmacología , Bioensayo , Ciclooxigenasa 1 , Ciclooxigenasa 2/metabolismo , Inhibidores de la Ciclooxigenasa 2/farmacología , Simulación del Acoplamiento Molecular , Estructura Molecular , Fenilbutiratos , Relación Estructura-Actividad
2.
Am J Epidemiol ; 184(2): 120-8, 2016 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-27370792

RESUMEN

Occupational noise exposure is associated with cardiovascular disease, but little is known about the contributions of noise frequency components. This retrospective study investigated the relationship between exposure to different noise frequencies and the incidence of hypertension. A cohort of 1,002 volunteers from 4 machinery and equipment manufacturing companies in Taichung, Taiwan, was followed from 1973 to 2012. Personal noise measurements and environmental octave-band analyses were performed to divide subjects into different exposure groups. Cox regression models were used to estimate the relative risk of hypertension. Participants exposed to ≥80 A-weighted decibels (dBA) over 8 years had a higher relative risk of hypertension (relative risk = 1.38, 95% confidence interval: 1.02, 1.85) compared with those exposed to <75 dBA. Significant exposure-response patterns were observed between incident hypertension and stratum of noise exposure at frequencies of 250 Hz, 1 kHz, 2 kHz, 4 kHz, and 8 kHz. The strongest effect was found at 4 kHz; a 20-dBA increase in noise exposure at 4 kHz was associated with a 34% higher risk of hypertension (relative risk = 1.34, 95% confidence interval: 1.01, 1.77). Occupational noise exposure may be associated with an increased risk of hypertension, and the 4 kHz component of occupational noise exposure may have the strongest relationship with hypertension.


Asunto(s)
Hipertensión/epidemiología , Ruido en el Ambiente de Trabajo/efectos adversos , Estudios de Casos y Controles , Femenino , Humanos , Hipertensión/etnología , Incidencia , Masculino , Exposición Profesional/efectos adversos , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Riesgo , Taiwán/epidemiología
3.
Adv Mater ; 36(15): e2307945, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38100238

RESUMEN

The emerging fields of wearables and the Internet of Things introduce the need for electronics and power sources with unconventional form factors: large area, customizable shape, and flexibility. Thermoelectric (TE) generators can power those systems by converting abundant waste heat into electricity, whereas the versatility of additive manufacturing suits heterogeneous form factors. Here, additive manufacturing of high-performing flexible TEs is proposed. Maskless and large-area patterning of Bi2Te3-based films is performed by laser powder bed fusion directly on plastic foil. Mechanical interlocking allows simultaneous patterning, sintering, and attachment of the films to the substrate without using organic binders that jeopardize the final performance. Material waste could be minimized by recycling the unexposed powder. The particular microstructure of the laser-printed material renders the-otherwise brittle-Bi2Te3 films highly flexible despite their high thickness. The films survive 500 extreme-bending cycles to a 0.76 mm radius. Power factors above 1500 µW m-1K-2 and a record-low sheet resistance for flexible TEs of 0.4 Ω sq-1 are achieved, leading to unprecedented potential for power generation. This versatile fabrication route enables innovative implementations, such as cuttable arrays adapting to specific applications in self-powered sensing, and energy harvesting from unusual scenarios like human skin and curved hot surfaces.

4.
Carbohydr Polym ; 291: 119549, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35698379

RESUMEN

A variety of cellulose-based polymer composite materials has been developed and show different impacts on the morphologies and properties of composites. Herein, we report the morphologies and properties of composites by blending polyurethane (PU) with either ethyl cellulose (EC) or cellulose nanofiber (CNF) through either drop-casting or electrospinning process. EC is homogenously mixed with PU without microphase separation and enhanced Young's modulus of composites from 0.04 to 6.94 MPa. The CNF is heterogeneously distributed in PU/CNF composites without interference on the PU microstructure and slightly increased modulus to 0.24 MPa. While the shearing force of the electrospinning process slightly affects the PU/EC composites, it drastically enhances PU crystallinity and Young's modulus to 54.95 MPa in PU/CNF composites. A model is established to summarize the effect of cellulose additives, compositions, and processes on PU/cellulose composites, providing a comprehensive understanding for designing future cellulose composites.


Asunto(s)
Nanofibras , Poliuretanos , Celulosa/química , Módulo de Elasticidad , Nanofibras/química , Polímeros/química , Poliuretanos/química
5.
Sci Rep ; 10(1): 8584, 2020 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-32444842

RESUMEN

Noise pollution is reported to be associated with diabetes, but few studies have elucidated the associations between noise frequency characteristics. We aimed to evaluate the relationships between different noise frequency components and incident hyperglycaemia. An industry-based cohort of 905 volunteers was enrolled and followed up to 2012. Octave-band frequencies of workstation noise and individual noise levels were measured in 2012 to classify subjects' exposures retrospectively. We applied Cox regression models to estimate the relative risk (RR) of hyperglycaemia. An increased RR for hyperglycaemia of 1.80 (95% confidence interval [CI]: 1.04, 3.10) was found among subjects exposed to ≥ 85 A-weighted decibels (dBA) compared with those exposed to < 70 dBA. The high-exposure groups at frequencies of 31.5, 63, 125, 250, 500, 1000, and 2000 Hz had a significantly higher risk of hyperglycaemia (all p values < 0.050) than the low-exposure groups. A 5-dB increase in noise frequencies at 31.5, 63, 125, 250, 500 Hz, and 1000 Hz was associated with an elevated risk of hyperglycaemia (all p values < 0.050), with the highest value of 1.27 (95% CI: 1.10, 1.47) at 31.5 Hz (p = 0.001). Occupational noise exposure may be associated with an increased incidence of hyperglycaemia, with the highest risk observed at 31.5 Hz.


Asunto(s)
Hiperglucemia/epidemiología , Ruido en el Ambiente de Trabajo/efectos adversos , Exposición Profesional/efectos adversos , Adulto , Femenino , Humanos , Hiperglucemia/etiología , Incidencia , Masculino , Pronóstico , Estudios Retrospectivos , Riesgo , Taiwán/epidemiología
6.
IEEE Trans Image Process ; 17(6): 968-81, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18482891

RESUMEN

This paper presents a new method for the relaxation of multiview registration error. The multiview registration problem is represented using a graph. Each node and each edge in the graph represents a 3-D data set and a pairwise registration, respectively. Assuming that all the pairwise registration processes have converged to fine results, this paper shows that the multiview registration problem can be converted into a quadratic programming problem of Lie algebra parameters. The constraints are obtained from every cycle of the graph to eliminate the accumulation errors of global registration. A linear solution is proposed to distribute the accumulation error to proper positions in the graph, as specified by the quadratic model. Since the proposed method does not involve the original 3-D data, it has low time and space complexity. Additionally, the proposed method can be embedded into a trust-region algorithm and, thus, can correctly handle the nonlinear effects of large accumulation errors, while preserving the global convergence property to the first-order critical point. Experimental results confirm both the efficiency and the accuracy of the proposed method.


Asunto(s)
Algoritmos , Inteligencia Artificial , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Técnica de Sustracción , Análisis Numérico Asistido por Computador , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Procesamiento de Señales Asistido por Computador
7.
Oncotarget ; 8(66): 110039-110051, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-29299128

RESUMEN

BACKGROUND: There are sex differences in the incidence and severity of cardiovascular disease. Although an estrogen-mediated vasculoprotective effect is widely accepted, clinical trial results have been conflicting and the detailed mechanisms are still unclear. Sirtuin 1 (SIRT1), a class III histone deacetylase, may protect against vascular aging and atherosclerosis; however, the effects of estrogen on SIRT1 expression and vascular smooth muscle cell (VSMC) behavior remain unknown. MATERIALS AND METHODS: We ovariectomized (OVX) female, wild-type, C57BL/6J mice, which were randomized into non-estrogen- and estrogen-supplemented groups. We also treated A7r5 VSMCs with 17-ß-estradiol and resveratrol, a SIRT1 activator, in vitro, and measured the expression of SIRT1 and apoptotic markers, as well as proliferation, viability, and migration. RESULTS: Aortic tissue from OVX mice exhibited marked VSMC hyperplasia and upregulation of SIRT1, which was reversed by 17-ß-estradiol supplementation, as assessed by western blotting and immunohistochemical staining. In vitro, 17-ß-estradiol downregulated SIRT1 expression in a dose- and time-dependent manner, increased apoptosis, and reduced proliferation, viability, and migration. Resveratrol reversed these effects through the activation of SIRT1. Estrogen appeared to mediate its effects through the Akt and ERK pathways. CONCLUSIONS: Estrogen may regulate cardiovascular health via the expression of SIRT1, possibly through the AKT and ERK signaling pathways.

8.
IEEE Trans Image Process ; 12(9): 1054-66, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-18237977

RESUMEN

In this paper, the Cramér-Rao lower bound (CRLB) of image registration error using an isotropic fiducial mark is derived. The derived CRLB is a function of the intensity profile of the fiducial mark. Following the development of the CRLB, a new method for designing an isotropic fiducial mark, suitable for digital image registration, is presented. A parameterization method of the fiducial intensity profile is introduced which guarantees no aliasing effect when the fiducial mark is digitized with the proper sampling rate. A method for computing the fiducial intensity profile, based on minimization of the CRLB registration error, and subject to certain practical constraints, is developed. For imaging systems with a significant low-pass effect, it is proposed to pre-emphasize the high frequency components of the fiducial mark by converting the designed gray-scale fiducial marks into binary fiducial marks. Experimental results show that the designed fiducial mark can provide very accurate registration results and that the registration accuracy is independent of its location.

9.
Comput Biol Med ; 44: 27-36, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24377686

RESUMEN

Many diseases associated with mental deterioration among aged patients can be effectively treated using neurological treatments. Research shows that electroencephalography (EEG) can be used as an independent prognostic indicator of morbidity and mortality. Unfortunately, EEG data are typically inaccessible to modern software. It is therefore important to design a comprehensive approach to integrate EEG results into institutional medical systems. A customized EEG system utilizing a database management approach was designed to bridge the gap between the commercial EEG software and hospital data management platforms. Practical and useful medical findings are discoursed from statistical analysis of large amounts of EEG data.


Asunto(s)
Bases de Datos Factuales , Electroencefalografía , Procesamiento de Señales Asistido por Computador , Programas Informáticos , Electroencefalografía/instrumentación , Electroencefalografía/métodos , Humanos
10.
J Agric Food Chem ; 60(19): 4854-8, 2012 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-22546171

RESUMEN

The dose-response relationship of the water-soluble carbohydrate concentrate (WSCC) from wild grape ( Vitis thunbergii Sieb. & Zucc.) on intestinal health was investigated in this study. WSCC contained carbohydrates up to 71.9 g/100 g, including arabinose-rich pectic polysaccharide, hemicelluloses, glucose, and fructose. The consumption of WSCC (0.5 and 1.5 g/100 g of diet) effectively (P < 0.05) shortened gastrointestinal transit time (-62.3 to -63.0%), decreased toxic cecal ammonia (-59.3 to -63.0%) and daily fecal ammonia output (-29.7 to -41.4%), decreased the activities of fecal ß-glucuronidase (-78.6%), ß-glucosidase (-80.5 to -87.5%), mucinase (-64.6 to -72.7%), and urease (-83.2 to -86.0%), increased fecal moisture content (116-129%), and also increased short-chain fatty acid levels in cecal contents (1.8-3.3-fold). These findings suggested that consumption of wild grape WSCC might diminish the exposure of intestinal mucosa to toxic ammonia and other detrimental compounds and, hence exert, favorable effects on improving gastrointestinal milieu.


Asunto(s)
Metabolismo de los Hidratos de Carbono , Carbohidratos/química , Mucosa Intestinal/metabolismo , Extractos Vegetales/química , Extractos Vegetales/metabolismo , Vitis/química , Amoníaco/metabolismo , Amoníaco/toxicidad , Animales , Ciego/metabolismo , Cricetinae , Humanos , Masculino , Mesocricetus , Solubilidad
11.
Int J Med Inform ; 77(12): 836-47, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18620903

RESUMEN

Recent advancements in modern medical diagnoses have required a huge increase of the use of equipment such as CT and ultrasound machines. Correspondingly, the storage and dissemination of these medical images have become an important issue to medical professionals. Unfortunately, management of these images has traditionally been slow and cumbersome. With the prevalence of the personal computer, however, along with increased network bandwidth, it is now possible to handle this information electronically as well as wirelessly. The Picture Archiving and Communication System (PACS) is at the forefront of this revolution. Yet, commercially available PACS software is generally prohibitively expensive for hospitals with limited financial resources. A dilemma among many hospitals is deciding how to acquire and implement the proper PACS system without unduly affecting the budget. In this paper, a full function, efficient, and economical PACS system is presented as a viable, non-compromising option for many small and medium-sized hospitals. This system, designed and developed mainly by the physicians and technicians of Puli Christian Hospital (PCH), with the assistance from academia, allows for customization to fit the needs of individual hospitals. This system can be used as the foundation of a hospital's health information infrastructure and to enhance e-hospital service.


Asunto(s)
Sistemas de Comunicación en Hospital , Sistemas de Información Radiológica , Humanos , Médicos
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