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1.
Phys Rev Lett ; 131(23): 236801, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38134770

RESUMO

Materials with negative longitudinal piezoelectric response have been a focus of recent research. So far, reported examples are mostly three-dimensional bulk materials, either compounds with strong ionic bonds or layered materials with van der Waals interlayer gaps. Here, we report the first example in two-dimensional elemental materials-the class of group-Va monolayers. From first-principles calculations, we show that these materials possess giant negative longitudinal piezoelectric coefficient e_{11}. Importantly, its physical mechanism is also distinct from all previous proposals, connected with the special buckling driven polarization in these elemental systems. As a result, the usually positive internal strain contribution to piezoelectricity becomes negative and even dominates over the clamped ion contribution in Bi monolayers. Based on this new mechanism, we also find several 2D crystal structures that may support negative longitudinal piezoelectricity. As another consequence, piezoelectric response in Bi monolayers exhibits a significant nonanalytic behavior, namely, the e_{11} coefficient takes sizably different values (differed by ∼18%) under tensile and compressive strains, a phenomenon not known before and helpful for the development of novel electromechanical devices.

2.
Biol Pharm Bull ; 46(11): 1569-1575, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37914359

RESUMO

Ovarian cancer (OC) is one of the most common and high mortality type of cancer among women worldwide. The majority of patients with OC respond to chemotherapy initially; however, most of them become resistant to chemotherapy and results in a high level of treatment failure in OC. Therefore, novel agents for the treatment of OC are urgently required. Benzimidazole anthelmintics might have the promising efficacy for cancer therapy as their selectively binding activity to ß-tubulin. Recent study has shown that one of the benzimidazole anthelmintics oxfendazole inhibited cell growth of non-small cell lung cancer cells, revealing its anti-cancer activity; however, the pharmacological action and detailed mechanism underlying the effects of oxfendazole on OC cells remain unclear. Therefore, the present study investigated the cytotoxic effects of oxfendazole on OC cells. Our results demonstrated that oxfendazole significantly decreased the viability of OC cells. Oxfendazole inhibited the proliferation, induced G2/M phase arrest and apoptotic cell death in A2780 cells. The c-Jun N-terminal kinase (JNK)/mitogen-activated protein kinase (MAPK) pathway was activated and reactive oxygen species (ROS) generation was increased in OC cells treated with oxfendazole; oxfendazole-induced apoptosis was notably abrogated when co-treated with JNK inhibitor SP600125 and ROS scavenger N-acetyl-L-cysteine (NAC), indicating that JNK/MAPK pathway activation and ROS accumulation was associated with the oxfendazole-induced apoptosis of OC cells. Moreover, oxfendazole could also induce the proliferation inhibition and apoptosis of cisplatin resistant cells. Collectively, these results revealed that oxfendazole may serve as a potential therapeutic agent for the treatment of OC.


Assuntos
Anti-Helmínticos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Neoplasias Ovarianas , Humanos , Feminino , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Neoplasias Ovarianas/tratamento farmacológico , Apoptose , Benzimidazóis/farmacologia , Sistema de Sinalização das MAP Quinases , Anti-Helmínticos/farmacologia
3.
J Reprod Immunol ; 158: 103969, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37295065

RESUMO

INTRODUCTION: There is abundant evidence to suggest that cytokines play a part in the mechanisms responsible for the formation of endometrium heterotopy. Cytokine synthesis is not only determined by the body's immunological reactivity but also by polymorphisms in the immune regulatory genes. The study of these polymorphisms in the immune regulatory genes offers up new possibilities in terms of prognosticating the risk of endometriosis and susceptibility to its treatment. The purpose of this comprehensive systematic review and meta-analysis was to investigate whether or not cytokine gene polymorphisms were linked to an increased chance of endometriosis. METHODS: By searching MEDLINE, Scopus, and Web of Science databases, the relevant studies were identified. The odds ratio (OR) with 95% confidence interval (CI) was used to assess the association between TNF-α/IL-10/IL-6/TGF-ß/IFN-γ/IL-1ß gene polymorphisms and endometriosis risk. RESULTS: A total of 5128 cases and 5334 controls in 32 eligible studies were included in the meta-analysis. Overall, results indicated the negative association between the cytokine gene polymorphisms and endometriosis in the dominant model of TNF-α (rs1799964): [OR] = 0.64, [CI]: 0.46-0.89) and a positive association in IFN-γ a13 allele: OR= 1.45, [CI]: 1.07-1.98; and IL-10 (rs1800872): [OR]= 1.60, [CI]: 1.21-2.12). CONCLUSION: The present study suggests that IL-10 (rs1800872) and IFN-γ a13 allele may be a risk factors for endometriosis. Also, TNF-α (rs1799964) is associated with decreased susceptibility to endometriosis.


Assuntos
Endometriose , Interleucina-10 , Feminino , Humanos , Interleucina-10/genética , Fator de Necrose Tumoral alfa/genética , Endometriose/genética , Polimorfismo de Nucleotídeo Único , Predisposição Genética para Doença , Citocinas/genética , Genótipo
4.
Virol J ; 8: 543, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22171842

RESUMO

Recently, we identified a novel porcine circovirus type 2-like agent P1 isolate from swine. The present study represents the first survey of P1 prevalence in swine herds from Jiangsu, China, by using PCR targeting the complete genome of P1. Prevalences of 50% and 19% were found among 6 herds and 248 animals, respectively. The results indicate a high prevalence of P1 in China pig populations.


Assuntos
Infecções por Circoviridae/veterinária , Circovirus/genética , DNA Viral/genética , Doenças dos Suínos/virologia , Animais , China , Infecções por Circoviridae/sangue , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/genética , Infecções por Circoviridae/virologia , Circovirus/isolamento & purificação , DNA Viral/sangue , DNA Viral/isolamento & purificação , Genótipo , Filogeografia , Reação em Cadeia da Polimerase , Prevalência , Suínos , Doenças dos Suínos/sangue , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/genética
5.
ACS Appl Mater Interfaces ; 13(38): 45924-45934, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34520164

RESUMO

Skin-like electronics that can provide comprehensively tactile sensing is required for applications such as soft robotics, health monitoring, medical treatment, and human-machine interfaces. In particular, the capacity to monitor the contact parameters such as the magnitude, direction, and contact location of external forces is crucial for skin-like tactile sensing devices. Herein, a flexible electronic skin which can measure and discriminate the contact parameters in real time is designed. It is fabricated by integrating the three-dimensional (3D) hollow MXene spheres/Ag NW hybrid nanocomposite-based embedded stretchable electrodes and T-ZnOw/PDMS film-based capacitive pressure sensors. To the best of our knowledge, it is the first stretchable electrode to utilize the 3D hollow MXene spheres with the essential characteristic, which can effectively avoid the drawbacks of stress concentration and shedding of the conductive layer. The strain-resistance module and the pressure-capacitance module show the excellent sensing performance in stability and response time, respectively. Moreover, a 6 × 6 sensor array is used as a demonstration to prove that it can realize the multiplex detection of random external force stimuli without mutual interference, illustrating its potential applications in biomimetic soft wearable devices, object recognition, and robotic manipulation.


Assuntos
Nanosferas/química , Pressão , Titânio/química , Dispositivos Eletrônicos Vestíveis , Condutividade Elétrica , Eletrodos , Nanocompostos/química , Nanofios/química , Maleabilidade , Prata/química , Estresse Mecânico
6.
Onco Targets Ther ; 13: 10323-10333, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33116612

RESUMO

BACKGROUND: Ovarian cancer (OC) is one of the most common causes of cancer-related death among women; accordingly, new biomarkers of OC are urgently needed. Potassium voltage-gated channel sub-family H member 3 (KCNH3) is a voltage-gated potassium channel member involved in cognitive function and diabetes. Here, we aimed to elucidate the role and potential molecular mechanisms of KCNH3 in OC. MATERIALS AND METHODS: KCNH3 expression levels in OC tissues were analyzed using TCGA data and confirmed by RT-qPCR and immunohistochemistry in OC tissues. The cell counting kit-8 was used to assess cell proliferation in OC cells in which KCNH3 was knocked-down with small interference RNA (siRNA). Wound-healing and transwell invasion assays were used to assess migratory and invasive abilities, respectively. Cell cycle distribution and apoptosis were determined using a flow cytometer. Gene set enrichment analysis and Western blot were used to investigate the potential pathways of KCNH3 in OC development. RESULTS: TCGA data and RT-qPCR results from patients with OC revealed high KCNH3 expression in OC tissues compared to normal ovarian tissues. Survival analysis in patients with OC suggested that high KCNH3 expression might be an independent predictor for poor overall survival and disease-free survival. In vitro studies showed that KCNH3 silencing in OC cells could inhibit cell proliferation and migration ability, and induce apoptosis and G2/M phase arrest. Furthermore, Western blot results showed that KCNH3 silencing might induce downregulation of RPA1 and RPA2 expression level in both SKOV3 and COC1 cells. CONCLUSION: KCNH3 plays an important role in cancer progression in patients with OC. Further investigation might reveal KCNH3 as a potential biomarker for prognosis or diagnosis in OC.

7.
ACS Omega ; 5(1): 864-870, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31956838

RESUMO

Two-dimensional materials with robust magnetic moments are of great interest to explore the exciting physics and applications of nanoscale spintronic devices. However, the antiferromagnetic (AFM) ground states often restrict the applications of symmetric MXenes. Herein, we proposed a kind of Janus structure for the V-based nitride MXene V2N with one V layer replaced by the Ti/Cr layer. In this work, we demonstrated from the first-principles calculations that although the AFM ground states are formed, the Janus TiVN and CrVN monolayers possess net magnetic moments of 1.97 and 0.28 µB per formula unit, respectively. Moreover, the net magnetic moments of TiVN and CrVN monolayers are robust even if considerable strains (-8 to 8%) are applied. Our results also show that TiVN and CrVN exhibit half-metallic and metallic features, respectively. These properties widen the potential applications of Janus V-based MXenes in spintronic or other electronic devices.

8.
Biosens Bioelectron ; 96: 26-32, 2017 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-28458131

RESUMO

Sensitive and accurate test of blood glucose levels is necessary to monitor and prevent diabetic complications. Herein, we developed a novel and sensitive non-enzymatic glucose sensing platform by employing 3D hierarchical porous Au networks (HPANs) as electrocatalyst for glucose oxidization. The HPANs were prepared through a bio-inspired synthesis method, in which the natural eggshell membrane (ESM) was introduced as template. The structure and properties of the as-prepared HPANs were characterized by a set of techniques, including scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), powder X-ray diffraction (XRD) and cyclic voltammetry (CV). The HPANs showed high catalytic activity towards glucose oxidization due to the unique structure. Inspiringly, the HPANs-based electrochemical glucose sensor could be driven at low potential (+0.1V) and showed an outstanding performance for glucose determination with two linear ranges of 1-500µM and 4.0-12mM, a limit of detection (LOD) of 0.2µM (3σ), and fast response time (less than 2s). Moreover, the stability and anti-interference performance of developed sensor was also excellent, enabling its preliminary application in clinical sample (human serum) test. Significantly, this work offered an environmentally friendly method for fabricating 3D nanostructure by using ESM (a biowaste) as template, setting up a typical example for producing new value-added nanomaterials with sensing application.


Assuntos
Técnicas Biossensoriais/métodos , Glicemia/análise , Casca de Ovo/química , Técnicas Eletroquímicas/métodos , Ouro/química , Nanoestruturas/química , Animais , Catálise , Galinhas , Eletrodos , Humanos , Sistemas de Infusão de Insulina , Limite de Detecção , Oxirredução , Tamanho da Partícula , Porosidade
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