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1.
Molecules ; 26(1)2020 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-33396531

RESUMEN

The aim of this study is to explore the effects of Manganese addition and homogenization treatment on the microstructures and mechanical properties of the Al-7Mg-0.15Ti (B535.0) alloy. The optical microscopy, electrical conductivity measurements, transmission electron microscopy, scanning electron microscopy (SEM + EBSD), as well as Rockwell hardness and tensile tests, were exploited for this purpose. The main objectives are to refine the grain size, inhibit grain growth in the annealed state, and enhance the mechanical strength of the alloy. The results show that the addition of manganese to the Al-7Mg-0.15Ti alloys refined the as-cast and recrystallized grains of the alloys. During the homogenization process, Al4Mn high-temperature stable dispersoids were precipitated in the aluminum matrix. After annealing, the Al4Mn particles blocked the movement of grain boundaries during the growth of the recrystallized grains and inhibited grain growth. Consequently, the annealed alloys showed grain refinement and dispersion strengthening. The Al4Mn dispersoids of the alloys with manganese added were smaller and denser after a two-stage homogenization process compared to those that underwent a one-stage homogenization process. By contrast, for the alloys without the addition of manganese, the recrystallized grains showed normal growth after annealing, and different homogenization processes had no significantly different effects.


Asunto(s)
Aleaciones/química , Aluminio/química , Manganeso/química , Titanio/química , Ensayo de Materiales , Estrés Mecánico , Propiedades de Superficie , Resistencia a la Tracción
2.
Zhonghua Nan Ke Xue ; 23(8): 739-744, 2017 Aug.
Artículo en Chino | MEDLINE | ID: mdl-29726651

RESUMEN

As more and more studies suggest that type 2 diabetes mellitus (T2DM) is closely related to male hypogonadism, people begin to pay more attention to the role of testosterone in the development of T2DM and the effect and safety of testosterone supplementary therapy. There is some controversy in randomized controlled studies and meta-analyses about the effects of testosterone supplementation on the blood glucose level, androgen deficiency symptoms, and cardiovascular diseases. This review focuses on the diagnosis of hypogonadism in T2DM males, differences in the therapeutic effects and safety of testosterone replacement among different studies, and rational use of testosterone supplementation for T2DM patients.


Asunto(s)
Diabetes Mellitus Tipo 2/etiología , Terapia de Reemplazo de Hormonas , Hipogonadismo/complicaciones , Testosterona/fisiología , Andrógenos/deficiencia , Glucemia , Enfermedades Cardiovasculares/etiología , Humanos , Hipogonadismo/diagnóstico , Hipogonadismo/tratamiento farmacológico , Masculino , Metaanálisis como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Testosterona/uso terapéutico
3.
Zhonghua Nan Ke Xue ; 22(12): 1088-1094, 2016 Dec.
Artículo en Chino | MEDLINE | ID: mdl-29282913

RESUMEN

OBJECTIVE: To compare the level of testosterone between type-2 diabetes mellitus (T2DM) patients and healthy controls and to investigate the status of hypogonadism and the influence of hypopgonadism on the quality of life. METHODS: We collected serum total testosterone (TT), free testosterone (FT), sex hormone-binding globulin (SHBG), and other clinical data from 166 T2DM patients aged over 30 years and 186 age-matched healthy controls. We investigated the quality of life (QoL) of the two groups of subjects using the questionnaires of Androgen Deficiency in Aging Males (ADAM), Aging Male Symptoms (AMS), 36-Item Short-Form Health Survey (SF-36), and Special Quality of Life for Diabetes Mellitus (DSQL). RESULTS: The level of calculated FT (cFT) was remarkably lower in the T2DM patients than in the healthy controls (P<0.05), but no statistically significant differences were observed between the two groups in the levels of TT, bio-available testosterone (Bio-T), and SHBG. The T2DM males with hypogonadism showed significant differences from those without in age, height, systolic blood pressure, and creatinine (P<0.05). Based on the criteria of cFT <0.3 nmol/L and AMS score ≥27, the incidence rate of hypogonadism was 51.81% in the T2DM patients, 31.58% in the 30-39 yr group, 32.50% in the 40-49 yr group, 50% in the 50-59 yr group, 69.23% in the 60-69 yr group, and 77.27% in the ≥70 yr group, elevated by 77.4% with the increase of 10 years of age (OR = 1.774, P<0.001). The AMS score was significantly correlated with the scores of DSQL (r = 0.557, P<0.001) and SF-36 (r = -0.739, P<0.001) in the T2DM patients. CONCLUSIONS: T2DM patients have lower levels of cFT than healthy men, accompanied with a higher incidence of hypogonadism. Age is a main risk factor of hypogonadism. Severer testosterone deficiency symptoms are associated with lower scores of QoL in T2DM males.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Hipogonadismo/complicaciones , Calidad de Vida , Estudios de Casos y Controles , Humanos , Incidencia , Masculino , Factores de Riesgo , Globulina de Unión a Hormona Sexual/análisis , Encuestas y Cuestionarios , Testosterona/sangre
4.
Artículo en Inglés | MEDLINE | ID: mdl-24110540

RESUMEN

Therapeutic ultrasound transducers can carry out precise and efficient power deposition for tumor thermal therapy under the guidance of magnetic resonance imaging. For a better heating, organ-specific ultrasound transducers with precision location control system should be developed for tumors located at various organs. It is feasible to perform a better heating for breast tumor thermal therapy with a ring-shaped ultrasound phased-array transducer. In this study, we developed ring-shaped phased-array ultrasound transducers with 1.0 and 2.5 MHz and a precision location control system to drive the transducers to the desired location to sonicate the designated region. Both thermo-sensitive hydrogel phantom and ex vivo fresh pork were used to evaluate the heating performance of the transducers. The results showed that the ring-shaped phased array ultrasound transducers were very promising for breast tumor heating with the variation of heating patterns and without overheating the ribs.


Asunto(s)
Neoplasias de la Mama/terapia , Terapia por Ultrasonido/métodos , Animales , Femenino , Ondas de Choque de Alta Energía , Humanos , Hipertermia Inducida , Imagen por Resonancia Magnética , Fantasmas de Imagen , Temperatura , Terapia por Ultrasonido/instrumentación
5.
Nat Prod Commun ; 7(11): 1435-40, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23285802

RESUMEN

Recent studies demonstrated that freshwater clam (Corbicula fluminea) has lipid-lowering and hepatoprotective activities, but its effect on immune responses has not yet been addressed. Here we showed that ethanol extracts of C. fluminea (ECF) reduced nitrite oxide, interleukin-1beta, interleukin-6, and tumor necrosis factor-alpha in lipopolysaccharide-activated macrophages. Further, ECF was fractionated into n-hexane, ethyl acetate, ethanol, and water soluble fractions. Of these, the ethyl acetate soluble fraction (EACF) had the highest capacity to inhibit pro-inflammatory mediators expression. The underlying mechanisms for the anti-inflammatory activity of EACF were demonstrated as down-regulation of ERK1/2, JNK1/2, and p38 phosphorylation and NF-kappaB activity. Using gas chromatography-mass spectrometric analysis EACF was found to be composed mainly of fatty acids and steroids. Our results provide evidence that freshwater clam has anti-inflammatory activity, and support the possibility for the development of freshwater clam as a health supplement or adjuvant therapeutic agent for either preventing or treating inflammation related diseases.


Asunto(s)
Bivalvos/química , Factores Inmunológicos/análisis , Macrófagos/efectos de los fármacos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Animales , Línea Celular , Activación Enzimática/efectos de los fármacos , Factores Inmunológicos/farmacología , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Lipopolisacáridos , Macrófagos/metabolismo , Ratones , Óxido Nítrico/metabolismo , Fosforilación/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismo
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