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1.
Nat Commun ; 15(1): 6782, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39117648

RESUMEN

Intermetallic alloys have traditionally been characterized by their inherent brittleness due to their lack of sufficient slip systems and absence of strain hardening. However, here we developed a single-phase B2 high-entropy intermetallic alloy that is both strong and plastic. Unlike conventional intermetallics, this high-entropy alloy features a highly distorted crystalline lattice with complex chemical order, leading to multiple slip systems and high flow stress. In addition, the alloy exhibits a dynamic hardening mechanism triggered by dislocation gliding that preserves its strength across a wide range of temperatures. As a result, this high-entropy intermetallic circumvents precipitous thermal softening, with extensive plastic flows even at high homologous temperatures, outperforming a variety of both body-centered cubic and B2 alloys. These findings reveal a promising direction for the development of intermetallic alloys with broad engineering applications.

2.
Zhonghua Liu Xing Bing Xue Za Zhi ; 39(5): 609-613, 2018 May 10.
Artículo en Chino | MEDLINE | ID: mdl-29860803

RESUMEN

Objective: To investigate the effects of high iodine intake on thyroid function in pregnant and lactating women. Methods: A cross sectional epidemiological study was conducted among 130 pregnant women and 220 lactating women aged 19-40 years in areas with high environment iodine level (>300 µg/L) or proper environment iodine level (50-100 µg/L) in Shanxi in 2014. The general information, urine samples and blood samples of the women surveyed and water samples were collected. The water and urine iodine levels were detected with arsenic and cerium catalysis spectrophotometric method, the blood TSH level was detected with electrochemiluminescence immunoassay, and thyroid stimulating hormone (FT(4)), antithyroid peroxidase autoantibody (TPOAb) and anti-thyroglobulin antibodies (TGAb) were detected with chemiluminescence immunoassay. Results: The median urine iodine levels of the four groups were 221.9, 282.5, 814.1 and 818.6 µg/L, respectively. The median serum FT(4) of lactating women in high iodine area and proper iodine area were 12.96 and 13.22 pmol/L, and the median serum TSH was 2.45 and 2.17 mIU/L, respectively. The median serum FT(4) of pregnant women in high iodine area and proper iodine area were 14.66 and 16.16 pmol/L, and the median serum TSH was 2.13 and 1.82 mIU/L, respectively. The serum FT(4) levels were lower and the abnormal rates of serum TSH were higher in lactating women than in pregnant women in both high iodine area and proper iodine area, the difference was statistically significant (FT(4): Z=-6.677, -4.041, P<0.01; TSH: Z=8.797, 8.910, P<0.01). In high iodine area, the abnormal rate of serum FT(4) in lactating women was higher than that in pregnant women, the difference was statistically significant (Z=7.338, P=0.007). The serum FT(4) level of lactating women in high iodine area was lower than that in proper iodine area, the difference was statistically significant (Z=-4.687, P=0.000). In high iodine area, the median serum FT(4) in early pregnancy, mid-pregnancy and late pregnancy was 16.26, 14.22 and 14.80 pmol/L, respectively, and the median serum TSH was 1.74, 1.91 and 2.38 mIU/L, respectively. In high iodine area, the serum FT(4) level in early pregnancy was higher than that in mid-pregnancy and late pregnancy, and the serum TSH level was lower than that in mid-pregnancy and late pregnancy, the difference was statistically significant (FT(4): Z=-2.174, -2.238, P<0.05; TSH: Z=-2.985, -1.978, P<0.05). There were no significant differences in the positive rates of serum thyroid autoantibodies among the four groups of women and women in different periods of pregnancy (P>0.05). The morbidity rates of subclinical hyperthyroidism in pregnant women and lactating women in high iodine area were obviously higher than those in proper iodine areas, the difference was statistically significant (χ(2)=5.363, 5.007, P<0.05). Conclusions: Excessive iodine intake might increase the risk of subclinical hypothyroidism in pregnant women and lactating women. It is suggested to strengthen the iodine nutrition and thyroid function monitoring in women, pregnant women and lactating women in areas with high environmental iodine.


Asunto(s)
Hipotiroidismo/epidemiología , Yoduros/administración & dosificación , Yodo , Lactancia , Embarazo , Enfermedades de la Tiroides/epidemiología , Glándula Tiroides/fisiología , Adulto , China/epidemiología , Estudios Transversales , Femenino , Humanos , Yodo/orina , Estado Nutricional , Prevalencia , Pruebas de Función de la Tiroides , Adulto Joven
3.
Osteoporos Int ; 23(1): 377-89, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22037970

RESUMEN

UNLABELLED: This study examined the role of estrogen receptor (ER) beta during mouse femoral fracture healing by employing ER knockout (KO) mice. The fracture healing in KO mice was enhanced in the early stage of neovascularization and the middle stage of endochondral ossification. INTRODUCTION: This study was conducted to examine the role of ER beta during fracture healing. METHODS: Female ERbeta knockout (KO) mice (18 weeks old) and age-matched female wild-type (WT) mice underwent open osteotomy on the right femur. They were sacrificed at 1, 2, 4 and 6 weeks post-fracture. The sera and callus samples were subjected to the following analyses: micro-computed tomography (CT)-based angiography, micro-CT evaluation, histological examination, histomorphometry examination, real-time polymerase chain reaction (PCR) analysis, biochemical marker, and mechanical testing. RESULTS: Micro-CT-based angiography showed that the total vessel volume at the fracture site was larger in the KO group than the WT group at 1 and 2 weeks post-fracture. Micro-CT analysis revealed that the callus volume was significantly higher in the KO group from week 2 to week 4 post-fracture when compared with the WT group consistent with the histological data. Analysis of biochemical markers indicated that circulating P1NP levels in the KO mice were significantly higher than in the WT mice from week 2 to week 4 and that temporal expression of circulating C-terminal telopeptide of type I collagen (CTX) levels was also higher in the KO mice than in the WT mice. These results were consistent with quantitative real-time PCR analysis. The ultimate load, stiffness, and energy to failure were significantly higher in the KO mice than in the WT mice at week 4. CONCLUSIONS: The fracture healing in KO mice was enhanced in the early stage of neovascularization and the middle stage of endochondral ossification, but not by the end of healing. Blockade of ERbeta can be considered as another therapeutic strategy for osteoporotic fracture and non-union fracture.


Asunto(s)
Receptor beta de Estrógeno/fisiología , Fracturas del Fémur/fisiopatología , Curación de Fractura/fisiología , Animales , Biomarcadores/sangre , Fenómenos Biomecánicos , Remodelación Ósea/fisiología , Callo Óseo/irrigación sanguínea , Callo Óseo/diagnóstico por imagen , Callo Óseo/fisiología , Colágeno Tipo I/sangre , Modelos Animales de Enfermedad , Receptor beta de Estrógeno/deficiencia , Receptor beta de Estrógeno/genética , Femenino , Fracturas del Fémur/diagnóstico por imagen , Fémur/irrigación sanguínea , Ratones , Ratones Noqueados , Neovascularización Fisiológica/fisiología , Osteotomía , Fragmentos de Péptidos/sangre , Péptidos/sangre , Procolágeno/sangre , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Microtomografía por Rayos X
4.
Artículo en Chino | MEDLINE | ID: mdl-21207704

RESUMEN

AIM: The protective effect of L-arginine on relative ischemia/reperfusion-induced myocardial injury was investigated in the rat isolated langendorff perfused heart. METHODS: Four groups of hearts subjected to 20 min electric stimulus and 40 min reperfusion received vehicle, L-arginine, N(omega)-nitro-L-arginine methyl ester and only stimulus respectively. RESULTS: The recovery of left ventricular developed pressure and pressure-rate product at the end of reperfusion was significantly higher in the L-arginine group (89.04% +/- 2.46% and 72.16% +/- 4.40%, respectively) than in the vehicle group (64.74% +/- 7.67% and 44.57% +/- 6.89%, respectively, P < 0.05). It is suggested that N(omega)-nitro-L-arginine methyl ester inhibits the recovery of the heart function after ischemia and accelerates the myocardial injury. CONCLUSION: We propose that it is important to protect the integrity of the heart angioendothelium during ischemia/reperfusion, and promote the synthesis of NO to relieve the myocardial injury and consequently accelerate the recovery of the heart function.


Asunto(s)
Daño por Reperfusión Miocárdica/metabolismo , Óxido Nítrico/metabolismo , Función Ventricular Izquierda , Animales , Técnicas In Vitro , Masculino , Daño por Reperfusión Miocárdica/fisiopatología , Ratas , Ratas Wistar
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