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1.
J Phys Chem Lett ; 13(50): 11669-11677, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36511504

RESUMO

Chiral tellurium nanoparticles have recently garnered tremendous attention as emerging inorganic nanomaterials with intrinsically chiral space groups owing to their potential in next-generation stereosynthesis, spintronics, and optoelectronics. Inspired by the chiral ligand-mediated synthetic strategy, we herein present hydrothermal-assisted synthesis of chiral polyhedral tellurium nanoparticles that provides differed chirogenesis than that of particles fabricated by wet chemistry in recent studies; the thiolated cysteine molecules change the morphology of tellurium nanoparticles from fundamental two-dimensional shapes to chiral three-dimensional polyhedra owing to the screw dislocation effects observed only during nanoparticle growth. However, the nanoparticles do not exhibit chiral behaviors at the nucleation stage. Further investigation indicates that the growth of chiral polyhedral tellurium nanoparticles is overwhelmingly affected by parameters such as the hydrothermal reaction time, amount of polyvinylpyrrolidone, and species of chiral molecules. We believe that these findings can provide new insights into the fundamental relationships among structural chirality, chiral ligands, screw dislocations, and chiral space groups in principle.

2.
Front Public Health ; 10: 842750, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35309214

RESUMO

In tunnels, lighting not only affects visual performance, but also non-visual aspects such as drivers' physiological fatigue and mental stress. The non-visual impacts in the interior zone of long tunnels are particularly prominent as drivers are confined for a long time. To alleviate this problem, this study aims to investigate the relationship between drivers' physiological and psychological states and lighting environments. The physiological signal test system (MP150) breathing belt was used to record the changes of heart rate variability (HRV) of drivers when passing through the interior zone of a long tunnel under various lighting conditions. In particular, sympathetic indicators of physiological fatigues and the ratio of low frequency and high frequency (LF/HF) representing mental load were obtained. By analyzing the temporal variation in these two indicators, it is found that environmental luminance perception can more accurately reflect drivers' physiological and psychological states in the long tunnel than road luminance. An increase in road luminance or background luminance will result in a decrease in the mental stress, thereby reducing fatigue sense. Compared to simply increasing road luminance, mental stress of drivers decreased more obviously when the background luminance of long tunnel increased. Based on this, this paper proposed a method to regulate non-visual effect by adding contour markers without increasing light source intensity for the improvement in lighting performance, driving safety, and energy efficiency in long tunnels.


Assuntos
Condução de Veículo , Condução de Veículo/psicologia , Fadiga , Humanos , Visão Ocular
3.
J Reprod Dev ; 63(3): 325-332, 2017 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-28381667

RESUMO

During mammary gland involution, the epithelial mesenchymal transition (EMT) process plays an important role in tissue remodelling and in the termination of milk production. Transforming growth factor ß (TGFß) has been known as a central inducer to EMT and contributor to the mammary gland involution. However, the whole mechanism has accomplished the EMT process in mammary gland is still unclear. Here, we show that arachidonic acid, one of the major products in milk, is new player to control the EMT together with TGFß during mammary gland involution. Firstly, we observed decrease in CDH1 (epithelial marker gene) expression and increases in VIM and TWIST1 (mesenchymal marker genes), TGFB1, and PLCG2 (arachidonic acid synthesis gene) at involution. In epithelial cells culture experiments, depletion of lactogenic hormones to mimic the involution induced TGFß1 and PLCG2 expressions. Treatment with arachidonic acid in epithelial cells increased VIM and TWIST1 expressions without decrease of CDH1 expression, while TGFß1 decreased CDH1 and increased VIM and TWIST1; more importantly, TGFß1 induced the expression of PLCG2, but arachidonic acid did not induce the expression of TGFB1. Finally, arachidonic acid accelerated the TGFß1 increasing VIM and TWIST1 expressions, meanwhile arachidonic acid synthase inhibitor partially blocked the TGFß1 increasing VIM and TWIST1 expressions. In conclusion, TGFß1 stimulates arachidonic acid synthesis and the arachidonic acid has a function to postulate the EMT process together with TGFß1 during mammary gland involution.


Assuntos
Ácido Araquidônico/metabolismo , Transição Epitelial-Mesenquimal , Glândulas Mamárias Animais/fisiologia , Fator de Crescimento Transformador beta1/metabolismo , Animais , Feminino , Camundongos Endogâmicos ICR
4.
Int J Endocrinol ; 2015: 283085, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25802518

RESUMO

One specific physiological phenomenon of Chinese brown frog (Rana dybowskii) is that its oviduct expands prior to hibernation instead of expanding during the breeding period. In this study, we investigated the expression of P450arom and estrogen receptors α and ß (ERα and ERß) in the oviduct of Rana dybowskii during the breeding period and prehibernation. The results of the present study showed that there were significant differences in both oviductal weight and size with values markedly higher in prehibernation than in the breeding period. P450arom was observed in stromal tissue in both the breeding period and prehibernation. ERα was expressed in stromal tissue and epithelial cells in both periods, whereas ERß could not be detected. The mean protein and mRNA levels of P450arom and ERα were significantly higher in prehibernation as compared to the breeding period. Besides, oviductal content of 17ß-estradiol was also higher in prehibernation than in the breeding period. These results suggested that estrogen may play autocrine/paracrine roles mediated by ERα in regulating the oviductal hypertrophy during prehibernation.

5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(4): 903-5, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23841395

RESUMO

The spectral resolution is one of the most important indexes of spectrometer. A new method is put forward for measuring the superhigh spectral resolution based on the Rayleigh criterion and the optical heterodyne, and the uncertainty of this method is analyzed. The spectral resolution of some spectrometer was measured using this method, and the experimental results show that the spectral resolution is higher than 18.9 pm, and the standard uncertainty is 2.3 pm. When showed using wave number, the spectral resolution is higher than 0.078 8 cm(-1), and the standard uncertainty is 0.009 6 cm(-1).

6.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 30(2): 193-6, 2005 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-15898433

RESUMO

OBJECTIVE: To determine the effects of exogenous RASSF1A gene on the proliferation and expression of P65 and subunit of NF-kappaB, in lung adenocarcinoma cell line A549. METHODS: pcDNA3.0-RASSF1A and pcDNA3. 0 were introduced into A549 cell line by lipofectin transfection, and the A549 cells stably expressing RASSF1A gene were established by G418 selection. The expression of RASSF1A was detected by Western blotting. The cytobiologic characterizations of the positive clone were analyzed by methythiazoletertraolium (MTT) assay and cytometry. The expressing of P65 was analyzed by RT-PCR and Western blotting. RESULTS: A549 cells stably expressing RASSF1A protein were established by lipofection mediated transfection and selected for further study. Compared with the nontransfected and vector transfected cells, the positive clone cells grew more slowly. Flow cytometric data showed that more positive clone cells went into phase G0/G1 and fewer cells went into phase S. The expression of P65 in nuclear protein in positive clone cells was lower than that of the control group while there was no obvious difference between the expression of p65 mRNA and P65 protein in total protein among the 3 groups. CONCLUSION: RASSF1A gene might suppress the proliferation of A549 cells through blocking the activity of P65 protein.


Assuntos
Adenocarcinoma/genética , Adenocarcinoma/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Proteínas Supressoras de Tumor/biossíntese , Linhagem Celular Tumoral , Proliferação de Células , Humanos , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Fator de Transcrição RelA/biossíntese , Fator de Transcrição RelA/genética , Transfecção , Proteínas Supressoras de Tumor/genética
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