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1.
Nanomaterials (Basel) ; 14(8)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38668174

RESUMO

A layered Ti3C2Tx MXene structure was prepared by etching MAX-phase Ti3AlC2 with hydro-fluoric acid (HF), followed by alkalization in sodium hydroxide (NaOH) solutions of varying concentrations and for varying durations. Compared to sensors utilizing unalkalized Ti3C2Tx, those employing alkalized Ti3C2Tx MXene exhibited enhanced sensitivity for NH3 detection at room temperature and a relative humidity of 40%. Both the concentration of NaOH and duration of alkalization significantly influenced sensor performance. Among the tested conditions, Ti3C2Tx MXene alkalized with a 5 M NaOH solution for 12 h exhibited optimal performance, with high response values of 100.3% and a rapid response/recovery time of 73 s and 38 s, respectively. The improved sensitivity of NH3 detection can be attributed to the heightened NH3 adsorption capability of oxygen-rich terminals obtained through the alkalization treatment. This is consistent with the observed increase in the ratio of oxygen to fluorine atoms on the surface terminations of the alkalization-treated Ti3C2Tx. These findings suggest that the gas-sensing characteristics of Ti3C2Tx MXene can be finely tuned and optimized through a carefully tailored alkalization process, offering a viable approach to realizing high-performance Ti3C2Tx MXene gas sensors, particularly for NH3 sensing applications.

2.
Vet Res ; 55(1): 26, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38414065

RESUMO

Pyroptosis is a form of programmed cell death characterized by cell swelling, pore formation in the plasma membrane, lysis, and releases of cytoplasmic contents. To date, the molecular mechanism of human and murine Gasdermin D-mediated pyroptosis have been fully investigated. However, studies focusing on molecular mechanism of bovine Gasdermin D (bGSDMD)-mediated pyroptosis and its function against pathogenic infection were unclear. In the present study, we demonstrate that bovine caspase-1 (bCaspase-1) cleaves bGSDMD at amino acid residue D277 to produce an N-terminal fragment (bGSDMD-p30) which leads to pyroptosis. The amino acid residues T238 and F239 are critical for bGSDMD-p30-mediated pyroptosis. The loop aa 278-299, L293 and A380 are the key sites for autoinhibitory structure of the full length of bGSDMD. In addition, bCaspase-3 also cleaves bGSDMD at residue Asp86 without inducing cell death. Therefore, our study provides the first detailed elucidation of the mechanism of bovine GSDMD-mediated pyroptosis. The results will establish a significant foundation for future research on the role of pyroptosis in bovine infectious diseases.


Assuntos
Gasderminas , Piroptose , Animais , Bovinos , Humanos , Camundongos , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Aminoácidos , Inflamassomos/metabolismo
3.
Vet Microbiol ; 288: 109922, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38086162

RESUMO

Mycobacterial PE_PGRS family proteins play key roles in pathogen-host interaction. However, the function of most PE_PGRS proteins remains unknown. In this study, we characterized the role of PE12 of Mycobacterium bovis (M. bovis) on bacterial growth, bacterial survival, and host cell apoptosis. Transcriptome sequencing of infected THP-1 cells was also performed. Compared to Ms_Vec, we found that M. bovis PE12 did not alter the colony morphology of M. smegmatis. The survival of Ms_PE12 was obviously higher than that of Ms_Vec. Furthermore, PE12 significantly suppressed the apoptosis of THP-1 induced by M. smegmatis infection. Transcriptome analysis results showed that there were 70 downregulated genes in the Ms_PE12 infection group in comparison with the Ms_Vec infection group, and these differentially expressed genes were enriched in 240 downregulated GO terms and 6 KEGG pathways. The downregulated expression genes are involved in cell adhesion, phagocytosis, apoptosis, inflammatory response, glycolysis and transmembrane transporter activity. Taken together, our study reveals that PE12 can suppress apoptosis and inhibit proinflammatory cytokine response. We propose that PE12 is related to macrophage phagocytosis and apoptosis, providing useful information to the pathogenic mechanisms of M. bovis.


Assuntos
Mycobacterium bovis , Mycobacterium tuberculosis , Animais , Mycobacterium smegmatis/genética , Mycobacterium smegmatis/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Macrófagos/microbiologia , Citocinas/metabolismo , Apoptose , Fagocitose , Mycobacterium tuberculosis/genética
4.
Clin Res Hepatol Gastroenterol ; 47(7): 102149, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37247692

RESUMO

OBJECTIVE: Cell division cycle 42 (CDC42) facilitates immune escape and drug resistance towards immunotherapy in several malignancies. This prospective study aimed to explore the predictive value of serum CDC42 for immune checkpoint inhibitor (ICI)-treatment response and survival in advanced hepatocellular carcinoma (HCC) patients. METHODS: Thirty advanced HCC patients scheduled for ICI or ICI-based treatment were enrolled in this prospective study, whose serum CDC42 was determined via enzyme-linked immunosorbent assay before therapy initiation. RESULTS: The median (interquartile range) of serum CDC42 level was 766.5 (605.0-1329.5) pg/mL. Serum CDC42 was related to increased tumor size but decreased programmed death-ligand 1 combined positive score (PD-L1 CPS). With respect to ICI or ICI-based treatment outcomes, elevated serum CDC42 was associated with decreased disease control rate, but did not link with objective response rate. Patients with high serum CDC42 (vs. low, cut by its median level) had shortened progression-free survival (PFS), while overall survival (OS) only disclosed a reduced trend (lacked statistical significance) in patients with high serum CDC42 (vs. low). In detail, the median (95%CI) PFS and OS were 3.0 (0.0-6.0) months and 11.7 (2.7-20.7) months in patients with high serum CDC42, while they were 11.1 (6.6-15.6) months and 19.3 (14.5-24.1) months in patients with low CDC42. After adjusted by multivariate cox regression analysis, high serum CDC42 (vs. low) was independently associated with shortened PFS, but not OS. CONCLUSIONS: Elevated serum CDC42 possesses a potential value in predicting worse ICI or ICI-based treatment outcomes in advanced HCC.


Assuntos
Carcinoma Hepatocelular , Proteínas de Ciclo Celular , Inibidores de Checkpoint Imunológico , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Estudos Prospectivos , Resultado do Tratamento
5.
Anal Chim Acta ; 1232: 340475, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36257746

RESUMO

Supramolecular host molecules are used as tools in the design of multifunctional nanoparticles for sensors, catalysts, biometric elements, etc. Combining with carbon dots (CDs) has excellent host-guest recognition properties and fluorescence characteristics, which can precisely capture and identify target analytes. Consequently, supramolecular host molecules-based CDs can significantly improve the detection performance of ions and molecules with different structures or intrinsic chemical properties. This currently responds to a wide range of analytes including metal cations, anions, organic compounds and other biomolecules, yielding fascinating achievements in the field of chemistry. Therefore, the present review summarizes outstanding supramolecular host molecules-based CDs reported in the past ten years. The focus is on elucidating the mechanisms, methodologies, advantages and disadvantages of modifying or preparing CDs with supramolecular host molecules. Current challenges encountered and outlooks are also be discussed.


Assuntos
Carbono , Pontos Quânticos , Carbono/química , Cátions , Catálise , Pontos Quânticos/química
6.
BMC Nurs ; 21(1): 281, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36253750

RESUMO

BACKGROUND: This study used the revised nursing outcomes classification (NOC) outlined in our previous study, "Core nursing outcomes for otorhinolaryngology head-neck," for telephone follow-up of patients who had laryngeal carcinoma surgery in China. This randomized controlled trial aimed to compare nurse-led telephone follow-up according to the revised NOC with traditional telephone follow-up. METHODS: A total of 100 postoperative patients were recruited from March 2018‒March 2020. Patients were randomly assigned to nurse-led telephone follow-up groups as either revised NOC follow-up (n = 51) or traditional follow-up (n = 49). The investigated outcomes included nursing outcomes, quality of life, and self-care abilities. RESULTS: The baseline characteristics of patients were well balanced. We noted that improvements in nursing outcomes in the intervention group were significantly better than for those in the control group (P = 0.018), primarily regarding psychosocial health (P < 0.001) and health knowledge and behavior (P < 0.001). Moreover, patient outcomes in the intervention group were associated with greater improvements in quality of life than those in the control group (P < 0.001), especially for social conditions (P < 0.001), emotional health (P < 0.001), functional status (P < 0.001), and additional attention (P = 0.001). Finally, compared with the control group, significant improvements were observed in self-care abilities in the intervention group (P = 0.002), mainly regarding general self-care abilities (P = 0.016) and development self-care abilities (P < 0.001). CONCLUSION: This study found that nurse-led telephone follow-up according to the revised NOC improved nursing outcomes, quality of life, and self-care abilities. TRIAL REGISTRATION: ChiCTR2100045941.

7.
J Matern Fetal Neonatal Med ; 35(26): 10551-10558, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36253882

RESUMO

BACKGROUND: Data of tenofovir alafenamide (TAF) in preventing mother-to-child transmission (MTCT) of hepatitis B virus (HBV) are limited. This study aimed to evaluate the effectiveness and safety of TAF for preventing MTCT. METHODS: Pregnant women with chronic HBV infection, positive for HBeAg and high-level HBV DNA, received oral TAF from gestational weeks 24-28 until postpartum week 4. All infants received HBV immunoprophylaxis. All mothers and infants were followed up until postpartum seven month. The primary outcome was the rate of MTCT at seven month. RESULTS: Eighty-nine mothers delivered and 91 infants were born. All were followed up to postpartum seven month. TAF was initiated at a mean gestational age of 25.0 (±1.0) weeks with the mean treatment duration of 14.3 (±1.2) weeks before delivery; 92.1% (82/89) mothers discontinued TAF, the median [IQR] time was 5.9 [4.7] weeks postpartum. The HBsAg positive rate was 0% at seven months in 91 infants, no growth retardation and congenital defects. All mothers were tolerated during TAF treatment. At delivery, 82.02% (73/89) mothers achieved HBV DNA < 200,000 IU/ml, 21.35% (19/89) achieved HBV DNA < 500 IU/ml. No significant changes on the mean (±SD) serum phosphate between baseline (1.20 ± 0.10 mmol/L) and at delivery (1.21 ± 0.13 mmol/L, p > .05). Serum creatinine at delivery (52.23 ± 8.50 µmol/L) was higher than baseline (45.97 ± 5.60 µmol/L, p < .05), but within normal range. Nine of 82 mothers stopped TAF treatment after delivery had mild ALT elevation. CONCLUSION: TAF therapy initiated during the second trimester was effective in preventing MTCT with no safety concerns for mothers and infants (ClinicalTrials.gov number, NCT04065230).


Assuntos
Hepatite B , Complicações Infecciosas na Gravidez , Lactente , Feminino , Gravidez , Humanos , Vírus da Hepatite B/genética , Tenofovir/efeitos adversos , Hepatite B/tratamento farmacológico , Hepatite B/prevenção & controle , Estudos Prospectivos , DNA Viral/uso terapêutico , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Antígenos E da Hepatite B/uso terapêutico , Antivirais/efeitos adversos
8.
Bioorg Med Chem ; 72: 116987, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-36049359

RESUMO

With advances in nanotechnology and the development of emerging therapeutic modalities, a surge in research on the use of nanomedicines for biomedical applications has occurred over the past three decades. Carbon dots (CDs) are new members of carbon-based nanomaterials that can be used in cancer treatment to reduce side effects of drugs and improve treatment efficiency, offering new medical opportunities for further research. Urged as such, we are encouraged to classify CDs-based cancer treatments, including photodynamic therapy (PDT), photothermal therapy (PTT), sonodynamic therapy (SDT), chemodynamic therapy (CDT), chemotherapy (CT), and synergistic therapy. The advantages of these approaches are summarized, as well as ways to improve certain shortcomings. Meanwhile, this review highlights the feasible practice of CDs in cancer treatment, which is further developed and widely used in the biomedical field.


Assuntos
Nanoestruturas , Neoplasias , Fotoquimioterapia , Carbono/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico
9.
Mikrochim Acta ; 189(10): 379, 2022 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-36087187

RESUMO

Metal-organic frameworks (MOFs) can be combined with nanomaterials and the combined composites have excellent optical properties. Carbon dots (CDs) with tiny particle size, non-toxic and rich surface functional groups are novel fluorescent materials. Carbon dots@metal-organic frameworks (CDs@MOFs) are synthesized by encapsulating CDs into MOFs. CDs@MOFs are promising composites for the preparation of a new generation of fluorescence sensors, which combine the hybrid properties of MOFs and the special optical properties of CDs. Urged as such, we are encouraged to categorize according to the sensing mechanisms. These include fluorescence resonance energy transfer (FRET), aggregation-caused quenching (ACQ), static quenching, dynamic quenching, photo-induced electron transfer (PET), inner filter effect (IFE) and so on. Based on the above mechanisms, CDs@MOFs can specifically interact with target analytes to generate fluorescence quenching. This review covers the research progress of CDs@MOFs in recent five years (with 103 refs), synthetic design of CDs@MOFs and introduces the sensing mechanism. The current challenges and future research directions are discussed briefly. The sensing mechanism and applications of CDs@MOFs.


Assuntos
Estruturas Metalorgânicas , Carbono , Transferência Ressonante de Energia de Fluorescência , Tamanho da Partícula
10.
Pak J Med Sci ; 38(4Part-II): 939-945, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35634597

RESUMO

Objectives: To study the value of serum miR21, human epididymal secretory protein 4 (HE4) and carbohydrate antigen 125 (CA125) in the surveillance for postoperative recurrent or metastatic ovarian cancer. Methods: A total of 169 patients diagnosed with ovarian conditions in Luanzhou Hospital of Traditional Chinese Medicine during January 2016 and March 2019 were divided into a benign lesion (BL) group and an ovarian cancer (OC) group by pathological findings and assigned to a good prognosis (GP) group and a poor prognosis (PP) group according to the follow-up results. A real-time fluorescence quantitative PCR (RT-fqPCR) system was utilized to detect the serum level of miR-21; an enzyme-linked immunosorbent assay (ELISA) was conducted to determine the serum level of HE4; electrochemiluminescence (ECL)-based imaging analysis was performed to measure serum CA125. A receiver operating characteristic (ROC) curve was depicted to analyze the predictive value of serum miR-21, HE4, and CA125 for poor postoperative prognosis in patients with ovarian cancer. Results: Compared with the control group, the BL and OC groups had substantially elevated expression of miR-21, HE4, and CA125 in serum, and the serum levels of miR-21, HE4, and CA125 in the OC group were significantly higher than in the BL group. In the OC group, the serum levels of miR-21, HE4, and CA125 were independent of age and pathological patterns and associated with the clinical staging, degree of transformation and lymphatic metastasis of ovarian cancer; after laparoscopic ovarian tumorectomy, the serum levels of miR-21, HE4, and CA125 were markedly reduced in comparison with the preoperative levels. Compared with the GP group, the PP group experienced a dramatic increase in serum miR-21, HE4, and CA125 expression. The ROC curve showed that the detection of miR-21, HE4, and CA125 was a highly sensitive and specific method to predict the poor prognosis in ovarian cancer; a patient with ovarian cancer was at high risk of a poor prognosis when the serum levels of miR-21, HE4, and CA125 exceeded 1.536, 157.004 pmol/L and 175.243 kU/L, respectively, in which case early intervention should be made to prevent recurrent or metastatic ovarian cancer. Conclusion: Elevated expression of miR-21, HE4, and CA125 in serum is closely associated with the disease status of ovarian cancer. Therefore, the simultaneous detection of these tumor markers has some diagnostic value for postoperative recurrence and metastasis of ovarian cancer.

11.
Sci Total Environ ; 820: 153262, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35065105

RESUMO

China is the main producer and consumer of rice in the world, and rice is a major staple food grain for more than half of the world's population. Reduced rice yields caused by climate factors not only affect the food security of China, but also has global repercussions. Thus, it is vital to assess the potential impact of climate warming on rice production. Using daily temperature and phenology records of double-cropping rice from agro-meteorological stations in southern China, the influence of increased temperatures on rice yields during the last several decades was investigated. Associated with an increase in average daily mean temperatures by 0.7 °C during 2009-2018 relative to 1961-1970, Killing Degree Days (KDD), an indicator for damaging high temperature, for early and late rice increased by 110% and 88.6% respectively. However, the negative influence of KDDs on yields was mainly evident for early rice, because high temperatures occurred frequently during the sensitive grain-filling period; early-rice yields showed a decrease of 8% per 1 °C increase in mean growing season air temperature. Late rice yields, on the other hand, were not as negatively influenced by increasing temperatures as early rice, because high temperature usually occurred during the vegetative growth stage, which was not so sensitive to high temperature.


Assuntos
Oryza , Agricultura , Clima , Mudança Climática , Temperatura
12.
J Healthc Eng ; 2021: 9886521, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34880982

RESUMO

The study focused on the clinical diagnostic value of color Doppler ultrasound of dangerous placenta previa patients under the guidance of intelligent recognition algorithms. 58 patients with placenta previa and placenta accreta admitted to the hospital for treatment were selected as research subjects. The color Doppler ultrasound under the guidance of intelligent recognition algorithm was compared with the two-dimensional ultrasound for specificity, sensitivity, and accuracy. The color Doppler ultrasound results showed that, of the 58 patients, there were 32 cases of complete placenta previa and 26 cases of incomplete placenta previa, which were consistent with the surgical pathology results. It was found that patients with malignant placenta previa and placenta accreta had thickened placenta, disappeared posterior placental space, myometrium <2 mm, and increased incidence of cervical enlargement (P < 0.05). In conclusion, the recognition accuracy of color Doppler ultrasound under the guidance of the intelligent recognition algorithm is more than 90%, and it can effectively identify dangerous placenta previa, assisting doctors in diagnosis and treatment of dangerous placenta previa.


Assuntos
Placenta Prévia , Algoritmos , Feminino , Humanos , Placenta/diagnóstico por imagem , Placenta Prévia/diagnóstico por imagem , Placenta Prévia/cirurgia , Gravidez , Ultrassonografia Doppler em Cores/métodos , Ultrassonografia Pré-Natal/métodos
13.
Mikrochim Acta ; 188(12): 412, 2021 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-34741664

RESUMO

Solid-state carbon dots (SCDs) have been widely investigated by scholars owing to their stability, environmental friendliness, and their good optical properties. The current studies on carbon dots (CDs) are mainly focused on the solutions of CDs, while the researches on SCDs are relatively few in comparison. Nowadays, the fabrication and design of high-performance SCDs have attracted much interest. However, due to resonance energy transfer and π-π interactions, CDs undergo aggregation-induced quenching (ACQ) phenomena. This poses an obstacle to the acquisition of SCDs and affects their luminescence performance. Publications of the past 5 years are reviewed on how to suppress the ACQ phenomenon and improve the fluorescence and phosphorescence emission of CDs (Ref. 87) and about the mechanism of achieving the luminescence of SCDs. Then, the applications of SCDs in the fields of luminescent devices, anti-counterfeiting, and detection are outlined. The concluding section analyzes the current challenges faced by SCDs and provides an outlook. Mechanism of photoluminescence from solid state carbon dots.

14.
BMC Nurs ; 20(1): 51, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33757518

RESUMO

BACKGROUND: The core nursing outcomes for laryngeal carcinoma in China needed further screening and revision. This study aimed to evaluate and revise a questionnaire according to the "Core Nursing Outcomes for Otorhinolaryngology Head-Neck" of the Nursing Outcomes Classification (NOC, 5th Edition), and determine suitable postoperative nursing outcomes for patients with laryngeal carcinoma in China. METHODS: The commonly used postoperative nursing outcomes for laryngeal carcinoma were screened using a questionnaire given to 93 nurses. An initial expert consultation questionnaire was constructed to discuss the indicators for each nursing outcome. A total of 20 experts were identified using the Delphi method, and their recommendations and revisions on the selected nursing outcomes were collected. RESULTS: A total of 14 postoperative core nursing outcomes and 69 indicators were identified for postoperative patients with laryngeal carcinoma, which are subordinate to 4 domains of the NOC: "Physiologic Health", "Psychosocial Health", "Health Knowledge & Behavior", and "Perceived Health". CONCLUSIONS: The screening and revision of the NOC outcomes and indicators of the Delphi method could be applied to assess the effect of nursing intervention and the quality of the nursing service in China.

15.
Gland Surg ; 10(12): 3362-3368, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35070896

RESUMO

BACKGROUND: The anti-tumor activity of pyrotinib has been confirmed in human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer. This study investigated the effect of pyrotinib plus nab-paclitaxel, doxorubicin, and cyclophosphamide as neoadjuvant therapy in patients with HER2-positive locally advanced breast cancer. METHODS: In this single-center retrospective study, female patients with HER2-positive locally advanced breast cancer received pyrotinib 320 mg orally once a day and the TAC regimen (nab-paclitaxel 260 mg/m2, liposomal doxorubicin 20 mg/m2, and cyclophosphamide 600 mg/m2) on day 1 of each 21-day cycle. Surgery was performed after 4-6 cycles of neoadjuvant therapy. The outcomes included total pathological complete response (tpCR, ypT0/Tis ypN0) rate, objective response rate (ORR) after neoadjuvant therapy, progression-free survival, overall survival, and the incidence of adverse events (AEs). RESULTS: Between March 2019 and January 2020, a total of 22 patients were included. The median age was 48 years (range, 32-60). The ORR was 100% after the completion of neoadjuvant therapy. Ten (45.5%) patients achieved tpCR, including four of ten (40.0%) patients with positive hormone receptor, and six of 12 (50.0%) patients with negative hormone receptor. As at December 2020, no disease recurrence, progression, or death occurred. All patients suffered AEs after neoadjuvant therapy, most of which were grade 1-2. Grade ≥3 AEs included diarrhea [4 (18.2%)], rash [2 (9.1%)], and hand-foot syndrome [1 (4.5%)]. CONCLUSIONS: Neoadjuvant pyrotinib combined with the TAC regimen showed promising clinical benefit in patients with HER2-positive locally advanced breast cancer, with an acceptable safety profile.

16.
World Neurosurg ; 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33065344

RESUMO

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found athttps://www.elsevier.com/about/our-business/policies/article-withdrawal.

17.
Nanotechnology ; 31(35): 355703, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32357357

RESUMO

Indium oxide (In2O3) nanowire field effect transistors (FETs) have great potential in electronic and sensor applications owing to their suitable band width and high electron mobility. However, the In2O3 nanowire FETs reported previously were operated in a depletion-mode, not suitable to the integrated circuits result of the high-power consumption. Therefore, tuning the electrical properties of In2O3 nanowire FETs into enhancement-mode is critical for the successful application in the fields of high-performance electronics, optoelectronics and detectors. In the work, a simple but effective strategy was carried out by preparing Ag nanoparticle functionalized In2O3 NWs to regulate the threshold voltage (Vth) of In2O3 NW FETs, successfully achieving enhanced-mode devices. The threshold voltage can be regulated from -6.9 V to +7 V by controlling Ag density via deposition time. In addition, the devices exhibited high performance: huge Ion/Ioff ratio > 108, large maximum saturation current ≈ 800 mA and excellent carrier mobility ≈ 129 cm2 Vcs-1. The enhanced performance is attributed to the surface passivation by Ag nanoparticles to reduce the density of traps and the charge transfer between traps and the nanowires to regulate the Vth. The result indicates the application of metal nanoparticles significantly improve oxide NW for low-power FETs.

18.
Mikrochim Acta ; 187(6): 344, 2020 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-32447460

RESUMO

Based on WS2 quantum dots (QDs) as fluorescent signals and MnO2 nanosheets as second-order scattering (SOS) signals, a combination of fluorescence and scattered light was used to construct a ratio sensing platform for glutathione (GSH) detection. When MnO2 nanosheets are added to WS2 QDs, the fluorescence of WS2 QDs is quenched by MnO2 nanosheets through IFE. Large-sized MnO2 nanosheets increase the SOS of the system and gradually approach the fluorescence. After adding GSH to WS2 QDs-MnO2, the MnO2 nanosheets were decomposed into Mn2+. The disappearance of the characteristic absorption peak of the MnO2 nanosheets suppressed the IFE to WS2 QDs, resulting in the fluorescence recovery of WS2 QDs. The reduction in size of MnO2 nanosheets after decomposition results in a decrease in the SOS of the system. Therefore, the ratio detection of GSH is obtained through the fluorescence and SOS dual signal response. Under optimal experimental conditions, the value of F406/S648 is linearly related to the GSH concentration in the range 0 to 60 µM, and the limit of detection (LOD) of GSH is 0.12 µM. In addition, the system is also used for the determination of GSH in real water samples and human serum, with good analytical results. Graphical abstract Schematic principle of fluorescence/scattered light system based on WS2 QDs-MnO2 for GSH ratiometric detection.


Assuntos
Corantes Fluorescentes/química , Glutationa/sangue , Compostos de Manganês/química , Óxidos/química , Pontos Quânticos/química , Espectrometria de Fluorescência/métodos , Água Potável/análise , Fluorescência , Corantes Fluorescentes/efeitos da radiação , Humanos , Limite de Detecção , Pontos Quânticos/efeitos da radiação , Sulfetos/química , Sulfetos/efeitos da radiação , Compostos de Tungstênio/química , Compostos de Tungstênio/efeitos da radiação
19.
Aging (Albany NY) ; 12(7): 6109-6119, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32259797

RESUMO

Oxygen and glucose deprivation (OGD)-reoxygenation (OGDR) induces oxidative injury to endometrial cells in vitro. We tested the potential effect of ginsenoside Rh3 (GRh3) in the process. Our results show that GRh3 activated Nrf2 signaling in T-HESC cells and primary murine endometrial cells. GRh3 induced Nrf2 Ser-40 phosphorylation and Keap1-Nrf2 disassociation, causing Nrf2 protein stabilization and nuclear translocation, which led to transcription and expression of antioxidant response element-dependent genes (HO1, NQO1 and GCLC). In T-HESC cells and primary murine endometrial cells, GRh3 potently attenuated OGDR-induced reactive oxygen species production, lipid peroxidation and mitochondrial depolarization, as well as cell viability reduction and necrosis. Activation of Nrf2 is required for GRh3-induced anti-OGDR actions in endometrial cells. Nrf2 inhibition, by Nrf2 shRNA, knockout (through CRISPR-Cas9-editing) or S40T mutation, abolished GRh3-induced endometrial cell protection against OGDR. Additionally, forced activation of Nrf2, by Keap1 knockout, mimicked and nullified GRh3-induced anti-OGDR actions in T-HESC cells. Together, we conclude that GRh3 protects endometrial cells from OGDR via activation of Nrf2 signaling.


Assuntos
Endométrio/metabolismo , Ginsenosídeos/farmacologia , Glucose/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Oxigênio/metabolismo , Animais , Células Cultivadas , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Camundongos , Estresse Oxidativo/fisiologia , Fosforilação , Substâncias Protetoras/farmacologia , Transdução de Sinais/efeitos dos fármacos
20.
Artigo em Inglês | MEDLINE | ID: mdl-32260284

RESUMO

Climate change has a distinct impact on agriculture in China, particularly in the northeast, a key agriculture area sensitive to extreme hydroclimate events. Using monthly climate and agriculture data, the influence of drought on maize and soybean yields-two of the main crops in the region-in northeast China since 1961 to 2017 were investigated. The results showed that the temperature in the growing season increased by 1.0 °C from the period 1998-2017 to the period 1961-1980, while the annual precipitation decreased slightly. However, precipitation trends varied throughout the growing season (May-September), increasing slightly in May and June, but decreasing in July, August and September, associated with the weakening of the East Asian summer monsoon. Consequently, the annual and growing season drought frequency increased by 15%, and 25%, respectively, in the period 1998-2017 relative to the period 1961-1980. The highest drought frequency (55%) was observed in September. At the same time, the drought intensity during the growing season increased by 7.8%. The increasing frequency and intensity of drought had negative influences on the two crops. During moderate drought years in the period 1961-2017, 3.2% and 10.4% of the provincial maize and soybean yields were lost, respectively. However, during more severe drought years, losses doubled for soybean (21.8%), but increased more than four-fold for maize (14.0%). Moreover, in comparison to the period 1961-1980, a higher proportion of the yields were lost in the period 1998-2017, particularly for maize, which increased by 15% (increase for soybean was 2.4%). This change largely depends on increasing droughts in August and September, when both crops are in their filling stages. The impact of drought on maize and soybean production was different during different growth stages, where a strong relationship was noted between drought and yield loss of soybean in its filling stage. Given the sensitivity of maize and soybean yields in northeast China to drought, and the observed production trends, climate change will likely have significant negative impacts on productivity in the future.


Assuntos
Agricultura , Secas , Glycine max , Zea mays , China , Mudança Climática
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