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1.
J Virol ; 98(5): e0019524, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38656209

RESUMO

The host cytoskeleton plays crucial roles in various stages of virus infection, including viral entry, transport, replication, and release. However, the specific mechanisms by which intermediate filaments are involved in orthoflavivirus infection have not been well understood. In this study, we demonstrate that the Japanese encephalitis virus (JEV) remodels the vimentin network, resulting in the formation of cage-like structures that support viral replication. Mechanistically, JEV NS1 and NS1' proteins induce the translocation of CDK1 from the nucleus to the cytoplasm and interact with it, leading to the phosphorylation of vimentin at Ser56. This phosphorylation event recruits PLK1, which further phosphorylates vimentin at Ser83. Consequently, these phosphorylation modifications convert the typically filamentous vimentin into non-filamentous "particles" or "squiggles." These vimentin "particles" or "squiggles" are then transported retrogradely along microtubules to the endoplasmic reticulum, where they form cage-like structures. Notably, NS1' is more effective than NS1 in triggering the CDK1-PLK1 cascade response. Overall, our study provides new insights into how JEV NS1 and NS1' proteins manipulate the vimentin network to facilitate efficient viral replication. IMPORTANCE: Japanese encephalitis virus (JEV) is a mosquito-borne orthoflavivirus that causes severe encephalitis in humans, particularly in Asia. Despite the availability of a safe and effective vaccine, JEV infection remains a significant public health threat due to limited vaccination coverage. Understanding the interactions between JEV and host proteins is essential for developing more effective antiviral strategies. In this study, we investigated the role of vimentin, an intermediate filament protein, in JEV replication. Our findings reveal that JEV NS1 and NS1' proteins induce vimentin rearrangement, resulting in the formation of cage-like structures that envelop the viral replication factories (RFs), thus facilitating efficient viral replication. Our research highlights the importance of the interplay between the cytoskeleton and orthoflavivirus, suggesting that targeting vimentin could be a promising approach for the development of antiviral strategies to inhibit JEV propagation.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Vimentina , Proteínas não Estruturais Virais , Replicação Viral , Animais , Humanos , Proteína Quinase CDC2/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Linhagem Celular , Vírus da Encefalite Japonesa (Espécie)/fisiologia , Vírus da Encefalite Japonesa (Espécie)/metabolismo , Encefalite Japonesa/virologia , Encefalite Japonesa/metabolismo , Células HEK293 , Interações Hospedeiro-Patógeno , Fosforilação , Quinase 1 Polo-Like , Proteínas Serina-Treonina Quinases/metabolismo , Vimentina/metabolismo , Proteínas não Estruturais Virais/metabolismo , Proteínas não Estruturais Virais/genética
2.
Nat Commun ; 15(1): 1809, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418489

RESUMO

Further increasing the critical temperature and/or decreasing the stabilized pressure are the general hopes for the hydride superconductors. Inspired by the low stabilized pressure associated with Ce 4f electrons in superconducting cerium superhydride and the high critical temperature in yttrium superhydride, we carry out seven independent runs to synthesize yttrium-cerium alloy hydrides. The synthetic process is examined by the Raman scattering and X-ray diffraction measurements. The superconductivity is obtained from the observed zero-resistance state with the detected onset critical temperatures in the range of 97-141 K. The upper critical field towards 0 K at pressure of 124 GPa is determined to be between 56 and 78 T by extrapolation of the results of the electrical transport measurements at applied magnetic fields. The analysis of the structural data and theoretical calculations suggest that the phase of Y0.5Ce0.5H9 in hexagonal structure with the space group of P63/mmc is stable in the studied pressure range. These results indicate that alloying superhydrides indeed can maintain relatively high critical temperature at relatively modest pressures accessible by laboratory conditions.

3.
Opt Lett ; 48(22): 5871-5874, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37966740

RESUMO

Recent advancements in optical convolutional neural networks (CNNs) and radar signal processing systems have brought an increasing need for the adoption of optical fast Fourier transform (OFFT). Presently, the fast Fourier transform (FFT) is executed using electronic means within prevailing architectures. However, this electronic approach faces limitations in terms of both speed and power consumption. Concurrently, existing OFFT systems struggle to balance the demands of large-scale processing and high precision simultaneously. In response, we introduce a novel, to the best of our knowledge, solution: a complex-valued matrix-vector system harnessed through wavelength selective switches (WSSs) for the realization of a 24-input optical FFT, achieving a high-accuracy level of 5.4 bits. This study capitalizes on the abundant wavelength resources available to present a feasible solution for an optical FFT system with a large N.

4.
J Phys Condens Matter ; 36(7)2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37918102

RESUMO

Clathrate hydrideFm3-m-LaH10has been proven as the most extraordinary superconductor with the critical temperatureTcabove 250 K upon compression of hundreds of GPa in recent years. A general hope is to reduce the stabilization pressure and maintain the highTcvalue of the specific phase in LaH10. However, strong structural instability distortsFm3-mstructure and leads to a rapid decrease ofTcat low pressures. Here, we investigate the phase stability and superconducting behaviors ofFm3-m-LaH10with enhanced chemical pre-compression through partly replacing La by Ce atoms from both experiments and calculations. For explicitly characterizing the synthesized hydride, we choose lanthanum-cerium alloy with stoichiometry composition of 1:1. X-ray diffraction and Raman scattering measurements reveal the stabilization ofFm3-m-La0.5Ce0.5H10in the pressure range of 140-160 GPa. Superconductivity withTcof 175 ± 2 K at 155 GPa is confirmed with the observation of the zero-resistivity state and supported by the theoretical calculations. These findings provide applicability in the future explorations for a large variety of hydrogen-rich hydrides.

5.
J Phys Chem Lett ; 13(49): 11521-11527, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36472637

RESUMO

One approach to discovering topological superconductors is establishing superconductivity based on well-identified topological insulators. However, the coexistence of superconductivity and a topological state is always arcane. In this paper, we report how pressure tunes the crystal structure, electronic structure, and superconductivity in topological insulator Bi2Te2.1Se0.9. At ∼2.5 GPa, the abnormal changes in c/a and the full width at half-maximum of the A1g1 mode indicate the occurrence of an electronic topological transition. The pressure-induced superconductivity in Bi2Te2.1Se0.9 pinned with an electronic topological transition presents at 2.4 GPa, which is far below the structural phase transition pressure of 8.4 GPa. These results suggest that the appearance of an electronic topological transition is closely correlated with superconductivity in the initial phase, where the topological surface state persists. Our work clarifies the complex electronic structure of Bi2Te2.1Se0.9 and sheds light on the mechanism for superconductivity in topological insulators.

6.
J Obstet Gynaecol ; 42(6): 2486-2491, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35678767

RESUMO

This retrospective cross-sectional study was to investigate factors affecting clinical pregnancy in patients who received gonadotropin-releasing hormone agonist luteal phase long protocol (GnRH-a long protocol) and underwent fresh in-vitro fertilisation (IVF)/intracytoplasmic sperm injection (ICSI) embryo transfer cycle. One thousand five hundred and twenty-five patients who received GnRH-a long protocol and underwent fresh IVF/ICSI embryo transfer cycle were enrolled. The clinical pregnancy rate (63.1 vs. 22.4%, p < .05) and live birth rate (53.8 vs. 14.5%, p < .05) were significantly higher while the miscarriage rate (12.5 vs. 35.3%, p < .05) was significantly lower in the two embryo group than those in the one embryo group. The clinical pregnancy rate (48.5 vs. 64.1%, p < .05) and live birth rate (38.4 vs. 55.0%, p < .05) were significantly lower in patients older than 33.5 years than those in younger patients. The clinical pregnancy rate (52 and 60.6 vs. 79.7%, p < .05) and live birth rate (36 and 51.4 vs. 69.6%, p < .05) of the thin and mediate groups were significantly lower than those in the thick group, whereas the ectopic pregnancy rate (11.5 and 1.9 vs. 0%, p < .05) was significantly higher in the thin group than in the mediate and thick group. Multivariate logistic regression analysis showed that age (OR = 0.956, 95% CI [0.931, 0.982], p < .05), number of embryos transferred (OR = 2.491, 95% CI [1.670, 3.715], p < .05) and endometrial thickness on the transplantation day (OR = 1.124, 95% CI [1.067, 1.185], p < .05) were independent factors significantly associated with clinical pregnancy. In conclusion, endometrial thickness (>14.69 mm) on the day of transfer, two cleavage embryos transferred, and female age (≤33.5 years) are independent factors affecting clinical pregnancy outcomes in controlled ovarian hyperstimulation with GnRH-a long protocol for assisted conception. IMPACT STATEMENTWhat is already known on this subject? Fresh embryo transfer cycle with GnRH-a long protocol will result in a higher pregnancy rate in controlled ovarian hyperstimulation cycles.What do the results of this study add? Endometrial thickness on the day of transfer, number of embryos transferred, and female age were independent factors affecting clinical pregnancy outcomes.What are the implications of these findings for clinical practice and/or further research? When performing a fresh IVF/ICSI embryo transfer cycle with GnRH-a long protocol for ovulation induction, the independent affecting factors should be taken into consideration.


Assuntos
Hormônio Liberador de Gonadotropina , Síndrome de Hiperestimulação Ovariana , Adulto , Estudos Transversais , Feminino , Fertilização in vitro/métodos , Humanos , Masculino , Indução da Ovulação/métodos , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Sêmen
7.
Artigo em Inglês | MEDLINE | ID: mdl-35627864

RESUMO

The influence of social and family factors on adolescent mental health has been widely valued. Considering adolescents' family systems in a broader social context facilitates a better understanding of their mental health, which also has special significance in the post-epidemic era. The purpose of the present study was to explore the relationship between social support and family functioning during adolescence. Students from two middle schools in Fujian province, China, were recruited as participants. Seven hundred and fifty-four participants completed the questionnaire twice in six-month intervals. We constructed a cross-lagged model by using IBM SPSS AMOS 26.0 to test the relationship between these two variables. Social support and family functioning predicted each other in the girls, but not for the boys' sample. The results of this study suggested that the interaction between family and social factors and the possible gender differences should be considered when dealing with adolescents' mental health problems.


Assuntos
Apoio Social , Estudantes , Adolescente , Feminino , Humanos , Masculino , Instituições Acadêmicas , Fatores Sexuais , Estudantes/psicologia , Inquéritos e Questionários
8.
Opt Lett ; 47(5): 1263-1266, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35230343

RESUMO

A diffractive lens based on metasurfaces has many advantages such as flatness, small aberrations, and compactness. The focal length can be adjusted by changing the lateral displacement between a pair of conjugate metasurfaces while fixing their axial distance, thereby forming a very compact zoom lens. However, chromatic aberration of diffractive optical elements restricts this system to working at one wavelength. This Letter proposes a metalens design method based on novel three-layer polarization-insensitive nanoposts, which can improve transmission amplitude and satisfy the achromatic zoom function with wavelengths ranging from 1310 nm to 1550 nm. The focal length can be adjusted from 31.2 µm to 19.8 µm, corresponding to extremal wavelength-dependent focal length relative deviation of 8.98%. This achromatic zoom metalens design method could have applications in various fields including augmented reality and integrated optical systems.

9.
Front Endocrinol (Lausanne) ; 12: 725202, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35027908

RESUMO

Objective: To investigate the effect of two treatments on the outcome of freeze-thaw embryo transfer for pregnancy assistance in thin endometrium. Methods: A retrospective study was conducted on 66 patients who failed in the first cycle treated in the reproductive medicine center of the Second Hospital of Hebei Medical University from January 2018 to December 2019. Granulocyte colony stimulating factor (G-CSF) was used through cavity infusion in one group (n=25, and growth hormone (GH) was subcutaneously injected in the group (n=41). The clinical data of the two groups were compared, including morphology and thickness of the endometrium, biochemical pregnancy rate, clinical pregnancy rate, implantation rate, miscarriage rate, and live birth rate in each period of the hormone replacement cycle. Results: There was no significant difference in age, BMI, AMH, FSH, LH, E2, infertility years, number of transferred embryos, basal endometrium, and thickness of endometrium on the day of P administration before and after treatment (P> 0.05). After treatment, compared to the GH group, the G-CSF group presented higher biochemical pregnancy rate (56% versus 48.8%; P=0.569), clinical pregnancy rate (52% versus 46.3%; P=0.655), implantation rate (34.8% versus 27.5%; P=0.391), and live birth rate (40% versus 31.7%; P=0.493), but the differences were not statistically significant (P > 0.05). On the 5th day of treatment, the endometrial thickness in the G-CSF group was thinner than that in the GH group (4.83 ± 0.85 versus 5.75 ± 1.27; P< 0.05), but it had no correlation with pregnancy outcome (P > 0.05). There was no significant difference in endometrial thickness between the two groups on the 7th, 9th day of treatment and the day of P administration (P > 0.05). On the 5th day of treatment, the proportion of endometrial type A morphology in the GH group was significantly higher than that in the G-CSF group (P < 0.05), while the type B morphology in the G-CSF group was significantly higher than that in the GH group (P< 0.05). Conclusion: Although G-CSF and GH may not have a role in increasing endometrium, both of them can improve the pregnancy outcomes of patients with thin endometrium in the FET cycle. And the effects of the two treatments were similar.


Assuntos
Implantação do Embrião/efeitos dos fármacos , Transferência Embrionária/estatística & dados numéricos , Endométrio/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Hormônio do Crescimento/administração & dosagem , Adulto , Criopreservação , Feminino , Humanos , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
10.
Front Endocrinol (Lausanne) ; 11: 592495, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33343510

RESUMO

Background: The risk of spontaneous abortion in patients with polycystic ovary syndrome (PCOS) undergoing assisted reproductive treatment (ART) is higher than that in patients without PCOS, however, no definitive risk factors have been confirmed to associate with the high spontaneous abortion rate in PCOS patients undergoing ART. This study was performed to assess the impact of relevant risk factors on spontaneous abortion in patients with PCOS. Clinical questions were formulated and organized according to the PICOS principle. Methods: A systematic review and meta-analysis were conducted on all published studies on PCOS and spontaneous abortion in Embase, PubMed, Web of Science and Cochrane Library. Related risk factors included body mass index (BMI), age, insulin resistance (IR), hyperandrogenism, and chromosome aberrations. All patients were diagnosed as PCOS using the Rotterdam criteria. The primary endpoint was miscarriage and live birth rate. Fixed-effect models were used to analyze homogeneous data, and subgroup and sensitivity analyses were performed on heterogeneous data. The source of heterogeneity was evaluated, and the random effect model was used to summarize the heterogeneity. Results: Among 1836 retrieved articles, 22 were eligible and included in the analysis with 11182 patients. High BMI (OR = 1.48, 95% CI [1.32, 1.67], MD = 1.35, 95% CI [0.58,2.12]) and insulin resistance (MD = 0.32, 95% CI [0.15, 0.49]) were associated with an increased risk of spontaneous abortion in PCOS patients undergoing ART. Older age (OR = 0.29, 95% CI [0.29, 0.44], MD = 2.01, 95% CI [0.04, 4.18]), embryonic chromosomal aberrations (OR = 0.75, 95%CI [0.31,1.77]), and hyperandrogenism (MD = 0.10, 95% CI [- 0.02, 0.22]) were not associated with the high spontaneous abortion rate in patients with PCOS. A subgroup analysis of BMI showed that there was no statistically significant difference in the effect between overweight and obesity on spontaneous abortion in PCOS patients undergoing ART (OR = 1.34, 95% [0.97, 1.85]). Conclusion: High BMI and insulin resistance are two risk factors for an increased risk of spontaneous abortion in PCOS patients undergoing ART, and losing weight and mitigating insulin resistance may decrease the spontaneous abortion rate in these patients undergoing ART.


Assuntos
Aborto Espontâneo/etiologia , Índice de Massa Corporal , Infertilidade Feminina/terapia , Resistência à Insulina , Síndrome do Ovário Policístico/fisiopatologia , Técnicas de Reprodução Assistida/efeitos adversos , Aborto Espontâneo/patologia , Feminino , Humanos , Gravidez
11.
Molecules ; 24(1)2018 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-30591651

RESUMO

The emergence and development of two-dimensional (2D) materials has provided a new direction for enhancing the thermoelectric (TE) performance due to their unique structural, physical and chemical properties. However, the TE performance measurement of 2D materials is a long-standing challenge owing to the experimental difficulties of precise control in samples and high demand in apparatus. Until now, there is no universal methodology for measuring the dimensionless TE figure of merit (ZT) (the core parameter for evaluating TE performance) of 2D materials systematically in experiments. Raman spectroscopy, with its rapid and nondestructive properties for probing samples, is undoubtedly a powerful tool for characterizing 2D materials as it is known as a spectroscopic 'Swiss-Army Knife'. Raman spectroscopy can be employed to measure the thermal conductivity of 2D materials and expected to be a systematic method in evaluating TE performance, boosting the development of thermoelectricity. In this review, thermoelectricity, 2D materials, and Raman techniques, as well as thermal conductivity measurements of 2D materials by Raman spectroscopy are introduced. The prospects of obtaining ZT and testing the TE performance of 2D materials by Raman spectroscopy in the future are also discussed.


Assuntos
Eletricidade , Teste de Materiais , Análise Espectral Raman , Temperatura , Fósforo/química
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