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1.
Nano Lett ; 24(29): 8818-8825, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38985501

RESUMO

Stationary energy storage infrastructure based on zinc-ion transport and storage chemistry is attracting more attention due to favorable metrics, including cost, safety, and recycling feasibility. However, splitting water and liquid electrolyte fluidity lead to cathode dissolution and Zn corrosion, resulting in rapid attenuation of the capacity and service life. Herein, a new architecture of solid-state electrolytes with high zinc ionic conductivity at room temperature was prepared via solidification of deep eutectic solvents utilizing MXene as nucleation additives. The ionic conductivity of MXene/ZCEs reached 6.69 × 10-4 S cm-1 at room temperature. Dendrite-free Zn plating/stripping with high reversibility can remain for over 2500 h. Subsequently, the fabricated solid-state zinc-ion battery with eliminated HER and suppressed Zn dendrites exhibited excellent cycling performance and could work normally in a range from -10 to 60 °C. This design inspired by eutectic solidification affords new insights into the multivalent solid electrochemistry suffering from slow ion migration.

2.
Anal Chem ; 96(32): 13260-13269, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39087711

RESUMO

The occurrence and development of diseases are accompanied by abnormal activity or concentration of biomarkers in cells, tissues, and blood. However, the insufficient sensitivity and accuracy of the available fluorescence probes hinder the precise monitoring of associated indexes in biological systems, which is generally due to the high probe intrinsic fluorescence and false-negative signal caused by the reactive oxygen species (ROS)-induced probe decomposition. To resolve these problems, we have engineered a ROS-stable, meso-carboxylate boron dipyrromethene (BODIPY)-based fluorescent probe, which displays quite a low background fluorescence due to the doubly quenched intrinsic fluorescence by a combined strategy of the photoinduced electron transfer (PET) effect and "ester-to-carboxylate" conversion. The probe achieved a high S/N ratio with ultrasensitivity and good selectivity toward biothiols, endowing its fast detection capability toward the biothiol level in 200×-diluted plasma samples. Using this probe, we achieved remarkable distinguishing of liver injury plasma from normal plasma even at 80× dilution. Moreover, owing to its good stability toward ROS, the probe was successfully employed for high-fidelity imaging of the negative fluctuation of the biothiol level in nonsmall-cell lung cancer (NSCLC) during dihydroartemisinin-induced ferroptosis. This delicate design of suppressing intrinsic fluorescence reveals insights into enhancing the sensitivity and accuracy of fluorescent probes toward the detection and imaging of biomarkers in the occurrence and development of diseases.


Assuntos
Artemisininas , Compostos de Boro , Ferroptose , Corantes Fluorescentes , Corantes Fluorescentes/química , Humanos , Artemisininas/farmacologia , Artemisininas/química , Compostos de Boro/química , Ferroptose/efeitos dos fármacos , Animais , Camundongos , Compostos de Sulfidrila/química , Imagem Óptica , Espécies Reativas de Oxigênio/metabolismo
3.
Small ; 20(5): e2305136, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37759415

RESUMO

This work addresses the challenges in developing carbon fiber paper-based supercapacitors (SCs) with high energy density by focusing on the limited capacity of carbon fiber. To overcome this limitation, a sponge-like porous carbon fiber paper enriched with oxygen functional groups (OFGs) is prepared, and Cu(OH)2 nanorods are grown on its surface to construct the SC anode. This design results in a multi-layered carbon fiber paper-based electrode with a specific structure and enhanced capacitance. The Cu(OH)2 @PCFP anode exhibits an areal capacitance of 547.83 mF cm-2 at a current density of 1 mA cm-2 and demonstrates excellent capacitance retention of 99.8% after 10 000 cycles. Theoretical calculations further confirm that the Cu(OH)2 /OFGs-graphite heterostructure exhibits higher conductivity, facilitating faster charge transfer. A solid-state SC is successfully assembled using Ketjen Black@PCFP as the cathode and KOH/PVA as the gel electrolyte. The resulting device exhibits an energy density of 0.21 Wh cm-2 at 1.50 mW cm-2 , surpassing the performance of reported Cu(OH)2 SCs. This approach, combining materials design with an understanding of underlying mechanisms, not only expands the range of electrode materials but also provides valuable insights for the development of high-capacity energy storage devices.

4.
Nanotechnology ; 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39378894

RESUMO

Temperature sensors find extensive applications in industrial production, defense, and military sectors. However, conventional temperature sensors are limited to operating temperatures below 200°C and are unsuitable for detecting extremely high temperatures. In this paper, a method for thermal protection of molybdenum disulfide (MoS2) films is proposed and a MoS2 high temperature sensor is prepared. By depositing a monolayer of Si3N4 onto MoS2, not only is the issue of high-temperature oxidation effectively addressed, but also the contamination by impurities that could potentially compromise the performance of MoS2 is prevented. Moreover, the width of the Schottky barrier of metal/MoS2 is reduced by using PECVD deposition of 400 nm Si3N4 to form an ohmic contact, which improves the electrical performance of the device by three orders of magnitude. The sensor exhibits a positive temperature coefficient measurement range of 25 to 550°C, with a maximum temperature coefficient of resistance (TCR) of 0.32%·°C-1. The thermal protection method proposed in this paper provides a new idea for the fabrication of high-temperature sensors, which is expected to be applied in the high-temperature field. .

5.
Nanotechnology ; 35(38)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38906118

RESUMO

Herein, we demonstrate an optimization of dye-sensitized solar cells (DSSCs) through the development of single-layer and double-layer configurations. Focusing on the incorporation of brookite and anatase phases in varying ratios, the study aims to determine the optimal composition for enhanced photovoltaic performance. The active layer, composed of anatase- and brookite-TiO2nanoparticles, is further modified with a scattering layer comprising a mixture of anatase nanoparticles and brookite-TiO2in the form of nanocube or rice-like particles. The synthesis of TiO2nanostructures with various morphologies and phase compositions and their subsequent application in single-layer and double-layer DSSCs are presented. The results highlight the superior light-harvesting capabilities achieved through the strategic incorporation of brookite phase into the anatase phase, emphasizing the importance of optimizing the anatase: brookite ratio. The single-layer DSSCs exhibit a peak efficiency of 8.73%, achieved with a composition of 30 wt.% brookite and 70 wt.% anatase at a thickness of 15µms. In the context of double-layer DSSCs, the combined optimization of the active layer composition, scattering layer morphology, and utilization of anatase nanoparticles leads to a remarkable efficiency of 9.18%. These findings underscore the critical role of composition and morphology in enhancing the performance of DSSCs, showcasing the potential for brookite-based DSSCs in solar energy conversion.

6.
Macromol Rapid Commun ; 45(17): e2400275, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38830087

RESUMO

The advent of nonfullerene acceptors (NFAs) has greatly improved the photovoltaic performance of organic solar cells (OSCs). However, to compete with other solar cell technologies, there is a pressing need for accelerated research and development of improved NFAs as well as their compatible wide bandgap polymer donors. In this study, a novel electron-withdrawing building block, succinimide-substituted thiophene (TS), is utilized for the first time to synthesize three wide bandgap polymer donors: PBDT-TS-C5, PBDT-TSBT-C12, and PBDTF-TSBT-C16. These polymers exhibit complementary bandgaps for efficient sunlight harvesting and suitable frontier energy levels for exciton dissociation when paired with the extensively studied NFA, Y6. Among these donors, PBDTF-TSBT-C16 demonstrates the highest hole mobility and a relatively low highest occupied molecular orbital (HOMO) energy level, attributed to the incorporation of thiophene spacers and electron-withdrawing fluorine substituents. OSC devices based on the blend of PBDTF-TSBT-C16:Y6 achieve the highest power conversion efficiency of 13.21%, with a short circuit current density (Jsc) of 26.83 mA cm-2, an open circuit voltage (Voc) of 0.80 V, and a fill factor of 0.62. Notably, the Voc × Jsc product reaches 21.46 mW cm-2, demonstrating the potential of TS as an electron acceptor building block for the development of high-performance wide bandgap polymer donors in OSCs.


Assuntos
Polímeros , Energia Solar , Succinimidas , Tiofenos , Tiofenos/química , Polímeros/química , Polímeros/síntese química , Succinimidas/química , Fontes de Energia Elétrica , Fulerenos/química , Estrutura Molecular
7.
BMC Psychiatry ; 24(1): 283, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627661

RESUMO

BACKGROUND: Depressive episodes in adolescents are often accompanied by various physical symptoms, but few studies have explored the association between depression and fever, This case study is the first to report the relationship between unexplained recurrent high fever and depression. CASE PRESENTATION: H is a 15 year old adolescent female currently in junior year. 2 + months ago, H gradually felt depressed after a class change. Around the time, the patient suddenly developed chills with no obvious trigger and fever. H was treated with anti-infective and anti-viral treatments all of which did not show significant improvement. No significant abnormality was seen in any of the related examinations. Considering that the patient's anxiety, depression and somatic symptoms were obvious during the course of the disease, she was given venlafaxine hydrochloride extended-release capsule 75 mg/d; tandospirone citrate capsule 10 mg Bid; alprazolam tablets 0.4 mg qn to improve mood and sleep; supplemented with transcranial repetitive magnetic stimulation therapy 2 times/d; visible light therapy 1 time/d and psychological counseling once. Over the 6 days of treatment, the patient's body temperature gradually returned to the normal range and her mood improved significantly. CONCLUSION: Depression should be considered a potential cause of unexplained recurrent fevers in adolescents, even when the temperature is significantly outside the normal range.


Assuntos
Psicoterapia , Humanos , Adolescente , Feminino , Cloridrato de Venlafaxina/uso terapêutico
9.
Biochem Genet ; 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38831231

RESUMO

Myocardial ischemic (MI) injury is a common cardiovascular disease, and the potential therapeutic effects of ginsenoside Rb2 (Rb2) have been lately the focus of interest. Therefore, this study aimed to investigate the effects of Rb2 on pyroptosis of cardiomyocytes in MI progression. An in vitro MI model was developed by subjecting rat's cardiomyocytes (H9c2) to hypoxia/reoxygenation (H/R). The cell viability was determined by CCK-8 assay, while cell death was analyzed by propidium iodide staining. Similarly, pyroptosis-related protein levels and acetylation levels of apoptosis-associated speck-like protein containing a CARD (ASC) were detected by western blotting, and the relationship between Sirtuin 1 (SIRT1) and ASC was confirmed by co-immunoprecipitation (Co-IP) assay. Moreover, hematoxylin-eosin (H&E) and triphenyl tetrazolium chloride staining were used to study pathological structure and infarct size. It was found that post-Rb2 treatment significantly increased the cell viability and decreased the cell death and lactic dehydrogenase release, while the increased gasdermin D-N, NOD-like receptor thermal protein domain-associated protein 3, ASC, and cleaved-caspase-1 protein levels were significantly decreased in H/R-stimulated H9c2 cells. Moreover, the acetylation levels of H92c cells were decreased post-Rb2 treatment via increasing SIRT1 levels, while knocking down SIRT1, translated into an increase in ASC acetylation levels, leading to the increase in ASC protein stability and expressions. Additionally, the Rb2 effects on pyroptosis in H/R-stimulated H92c cells were reversed by overexpressing ASC, while reduced myocardial tissue damage was observed in MI rats following in vivo Rb2 treatment. Rb2 treatment inhibited pyroptosis in MI progression by decreasing the ASC levels. Mechanistically, Rb2 treatment increased the SIRT1 levels, further increasing the acetylation levels of ASC and decreasing the protein stability of ASC.

10.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 49(2): 296-304, 2024 Feb 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-38755726

RESUMO

Traditional antibody drug conjugates (ADC) combine monoclonal antibodies with cytotoxic drugs to accurately strike cancer cells, but there are still many shortcomings in stability, targeting, efficacy, and safety. Novel ADC, such as bi-specific, site-specific, dual-payload, and pro-drug type ADC, can be optimized by simultaneously binding 2 different antigens or epitopes, selecting more stable linkers, coupling with specific amino acid sites of antibodies, carrying different drug payloads, and adopting prodrug strategies, while retaining the characteristics of traditional ADC. Significantly improving the stability, targeting, efficacy and safety of drugs can better meet the needs of clinical treatment. Novel ADC will play a more important role in cancer treatment in the future. Discussing the progress of novel ADC in cancer treatment and analyzing their advantages and challenges can provide theoretical support for the development of anti-cancer strategies and provide directions for drug research and development.


Assuntos
Imunoconjugados , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Imunoconjugados/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Pró-Fármacos/uso terapêutico
11.
Mol Cell Biochem ; 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37639200

RESUMO

Dysregulation of long non-coding RNAs (lncRNAs) is associated with the tumorigenesis and ferroptosis of non-small cell lung cancer (NSCLC). BBOX1 antisense RNA 1 (BBOX1-AS1) functions as an oncogenic driver in NSCLC. Here, we aim to investigate the regulation effect and underlying mechanism of BBOX1-AS1 in NSCLC progression and ferroptosis. RNA expression was detected by quantitative real-time PCR (qRT-PCR), and protein expression was measured by immunoblotting. Cell growth was assessed by CCK-8 and colony formation assays. Transwell assay was applied to evaluate cell invasion and migration. RNA pull-down and dual-luciferase reporter assays were applied to verify the relationship between miR-326 and BBOX1-AS1 or prominin 2 (PROM2). The role of BBOX1-AS1 in NSCLC tumorigenicity was also analyzed by xenograft assays. Silencing BBOX1-AS1 or PROM2 impeded NSCLC cell growth, migration, and invasion. Silencing BBOX1-AS1 induced cell apoptosis and ferroptosis. BBOX1-AS1 up-regulated PROM2 expression, and re-expression of PROM2 reversed the effects of BBOX1-AS1 depletion on cell malignant phenotypes and ferroptosis. BBOX1-AS1 post-transcriptionally modulated PROM2 expression by sponging miR-326. MiR-326 was validated as a mediator of BBOX1-AS1 in regulating NSCLC cell malignant phenotypes and ferroptosis. Additionally, BBOX1-AS1 deficiency in vivo resulted in the suppression of xenograft tumor growth. Together, our study defines a novel BBOX1-AS1/miR-326/PROM2 axis in regulating NSCLC malignant progression and ferroptosis, offering new evidence for the oncogenic role of BBOX1-AS1 in NSCLC. These findings may provide a basis for the future usage of targeting BBOX1-AS1 in NSCLC treatment.

12.
Opt Express ; 30(24): 43706-43717, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36523063

RESUMO

This paper reports a series of novel photodetectors based on one-dimensional array of metal-oxide-semiconductor field-effect transistors (MOSFETs), which were fabricated using the standard 0.8-µm complementary metal oxide semiconductor (CMOS) process. Normally, the metal fingers of MOSFET must be manufactured above active region in standard CMOS process, causing MOSFET insensitive to light. The proposed photodetectors use the metal fingers of MOSFETs in a one-dimensional array to form periodical slit structures, which make the transmittance of incident light higher, due to the surface plasmons (SPs) resonance effect. The number of parallel MOSFETs in one-dimensional array is 3, 5, 7, 9 and 11. The experimental results show that all responsivities (Rv) are greater than 103 A/W within visible and near-infrared spectra under room temperature and a maximum value of 1.40 × 105 A/W is achieved, which is at least one order of magnitude larger than those of published photodetectors. Furthermore, a minimum noise equivalent power (NEP) of 5.86 fW/Hz0.5 at 30 Hz and a maximum detectivity (D*) of 2.21 × 1013 Jones are obtained. The photodetectors still have good signal-to-noise ratio when the bandwidth is 1 GHz. At the same time, the optical scanning imaging was completed by utilizing the photodetectors. This combination of high Rv, excellent NEP, high speed and broad spectrum range photodetectors will be widely used in imaging systems.

13.
Macromol Rapid Commun ; 43(20): e2200325, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35524946

RESUMO

Organic semiconductors inherently have a low dielectric constant and hence high exciton binding energy, which is largely responsible for the rather low power conversion efficiency of organic solar cells as well as the requirements to achieve delicate bulk-heterojunction nanophase separation in the active layer. In this study, methyl acrylate as a weakly electron-withdrawing side chain for the electron rich thiophene to prepare a new building block, methyl thiophene-3-acrylate (TA), with increased polarity is used. A wide bandgap polymer PBDT-TA synthesized using TA and a benzodithiophene (BDT) monomer shows increased dielectric constant and reduced exciton binding energy compared to the analogous polymer PBDT-TC, which is made of BDT and methyl thiophene-3-carboxylate (TC). An organic solar cell device based on PBDT-TA:ITIC also achieves a higher power conversion efficiency of 10.47% than that of the PBDT-TC:ITIC based solar cell (9.68%). This work demonstrates the effectiveness of using acrylate side chains to increase the dielectric constant, reduce the exciton binding energy, and enhance the solar cell efficiency of polymer semiconductors.

14.
Biol Pharm Bull ; 45(1): 71-76, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34980781

RESUMO

The ginsenoside Rbs are the primary active compounds of Panax ginseng and ginsenoside Rb2 is a renowned component among the Rbs. This study aimed to investigate the potential effects of ginsenoside Rb2 on coronary heart disease (CHD). H9c2 cells were exposed to H2O2 to establish CHD model in vitro. Gene expression was determined by quantitative realtime PCR (qPCR) and Western blot. Cellular functions were detected by Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), flow cytometry, and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) assays. We found that Ginsenoside Rb2 promoted cell proliferation while suppressed oxidative stress and apoptosis of H9c2 cells induced by H2O2 exposure. Mechanistically, Ginsenodise Rb2 involves in the regulation of nuclear factor, erythroid 2 like 2 (Nrf2)/heme oxygenase (HO)-1 signaling pathway. Inactivation of Nrf2/HO-1 signaling pathway reversed the effects of ginsenoside Rb2 on H9c2 cells. Taken together, ginsenoside Rb2 exhibited a cardioprotective effect in vitro. The underlying mechanism of ginsenoside Rb2 in H9c2 cells could be standardized to Nrf2/HO-1 signaling pathway, inhibiting cell apoptosis and regaining cell proliferation. The present study has proposed a novel mechanism of ginsenoside Rb2 in the cardioprotective effect.


Assuntos
Doença das Coronárias , Ginsenosídeos , Apoptose , Ginsenosídeos/farmacologia , Ginsenosídeos/uso terapêutico , Humanos , Peróxido de Hidrogênio/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Transdução de Sinais
15.
Nanotechnology ; 33(7)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34062529

RESUMO

Unlike zero-bandgap graphene, molybdenum disulfide (MoS2) has an adjustable bandgap and high light absorption rate, hence photodetectors based on MoS2have attracted tremendous research attention. Most of the reported MoS2photodetectors adopted back-gate field-effect transistor (FET) structure due to its easy fabrication and modulation features. However, the back-gate FET structure requires very high gate voltage up to 100 V, and it is impossible to modulate each device in an array with this structure independently. This work demonstrated a monolayer MoS2photodetector based on a buried-gate FET structure whose experimental results showed that both the electrical and photoelectrical properties could be well modulated by a gate voltage as low as 3 V. A photoresponsivity above 1 A W-1was obtained under a 395 nm light-emitting diode light illumination, which is over 2 orders of magnitude higher than that of a reported back-gate photodetector based on monolayer MoS2(7.5 mA W-1). The photoresponsivity can be further improved by increasing the buried gate voltage and source-drain voltage. These results are of significance for the practical applications of MoS2photodetectors, especially in the low voltage and energy-saving areas.

16.
Nanotechnology ; 32(48)2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34412038

RESUMO

Temperature sensor is one of the primarily developed and most proverbially utilized sensors. Owing to the limitations of their characteristics (stability, thermal conductivity, and thermal contact area), traditional temperature sensors may exhibit drawbacks of high production cost and large volume. In this paper, a three-dimensional (3D) buried-gate graphene field effect transistors (GFETs) are proposed as a novel sensor for temperature detection, which possess a 3D microtube structure by self-rolled-up technology. Compared to conventional two-dimensional (2D) devices, the 3D devices would have tinier area and higher integration. Two main reasons that would affect the resistance of the graphene are the graphene electro-phonon coupling and the thermal expansion effect. In addition, by applying the COMSOL Multiphysics software, it has been demonstrated that the microtube would deform to a certain extent when the temperature increases. And the strain on the 3D devices is proved to be greater than that of the 2D devices. Experimental results show that 3D GFETs could realize temperature detection between 30 °C and 150 °C, and its resistance increases with temperature rising. Furthermore, the maximum achieved temperature coefficient of resistance (TCR) is 0.41% °C-1and the hysteresis error is only 3.85%. By virtue of the 3D microtube, not only more superior temperature detection could be achieved, but also more devices are integrated in unit area. The 3D temperature sensor possesses superior sensitivity, repeatability and stability, which contributes a new approach to develop the high-performance temperature sensor.

17.
Int J Clin Pract ; 75(5): e13981, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33405321

RESUMO

INTRODUCTION: The OM-85 (Broncho-Vaxom) consumption has drawn considerable attention in the prevention of recurrent respiratory tract infections. However, it has been reported that the relationship between OM-85 consumption and recurrent respiratory tract infections is variable. This meta-analysis was performed to evaluate this relationship. METHODS: A systematic literature search up-to May 2020 was performed and 14 studies were detected with 1859 paediatric subjects, of them 890 consumed OM-85. They were reporting relationships between OM-85 consumption and recurrent respiratory tract infections. Odds ratio (OR) or mean differences (MD) with 95% confidence intervals (CIs) was calculated to evaluate the prognostic role of OM-85 consumption and recurrent respiratory tract infections using the dichotomous or continuous method with a random or fixed-effect model. RESULTS: OM-85 consumption was significantly related to lower frequency of respiratory tract infections (MD, -1.16; 95% CI, -1.66 to -0.65, P < .001); lower total duration of respiratory tract infections (MD, -19.51; 95% CI, -23.00 to -16.01, P < .001); lower incidence of respiratory tract infections (OR, 0.40; 95% CI, 0.21-0.77, P = .006); lower number of antibiotic courses (MD, -1.40; 95% CI, -2.63 to 0.17, P = .03); and lower antibiotic use (OR, 0.38; 95% CI, 0.29-0.52, P < .001). However, OM-85 consumption was not significantly related to adverse event rate (OR, 1.02; 95% CI, 0.52-2.03, P = .94); or to wheezing attacks frequency (MD, -0.25; 95% CI, -0.59 to 0.08, P = .14). CONCLUSIONS: The impact of OM-85 consumption on recurrent respiratory tract infections may have a great effect as a tool to improve subjects' immunity against recurrent respiratory tract infections, which could be helpful in crucial situations, eg, COVID-19 pandemic. OM-85 non-consumers had an independent risk relationship with recurrent respiratory tract infections. This relationship forces us to recommend OM-85 consumption with those with a high risk of recurrent respiratory tract infections to avoid any possible complications.


Assuntos
COVID-19 , Infecções Respiratórias , Adjuvantes Imunológicos , Criança , Humanos , Pandemias , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/prevenção & controle , SARS-CoV-2
18.
Pestic Biochem Physiol ; 172: 104745, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518039

RESUMO

The fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae) is a polyphagous pest with 353 plant species as its hosts, including maize, sorghum, cotton, and rice. Azadirachtin is one of the most effective botanical insecticides. The effect of azadirachtin against S. frugiperda remains to be determined. Here we report strong growth inhibition of azadirachtin on S. frugiperda larvae under either 1.0 or 5.0 µg/g azadirachtin. To explore the relevant mechanisms, the larvae fed with normal artificial diet and with 1.0 µg/g azadirachtin exposure for 3 days were collected as samples for RNA-Seq. RNA-Seq on S. frugiperda larvae under different treatments identified a total of 24,153 unigenes, including 3494 novel genes, were identified. Among them, 1282 genes were affected by 1.0 µg/g azadirachtin exposure, with 672 up-regulated and 610 down-regulated. The impacted genes include 61 coding for detoxification enzymes (31 P450s, 7 GSTs, 11 CarEs, 7 UGTs and 5 ABC transporters), 31 for cuticle proteins, and several proteins involved in insect chitin and hormone biosynthesis. Our results indicated that azadirachtin could regulate the growth of S. frugiperda by affecting insect chitin and hormone biosynthesis pathway. The enhanced expression of detoxification enzymes might be related to detoxifying azadirachtin. These findings provided a foundation for further delineating the molecular mechanism of growth regulation induced by azadirachtin in S. frugiperda larvae.


Assuntos
Limoninas , RNA-Seq , Animais , Larva/genética , Limoninas/toxicidade , Spodoptera/genética , Zea mays/genética
19.
Chemphyschem ; 21(9): 895-907, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32107838

RESUMO

This work reports development of yttrium doped copper oxide (Y-CuO) as a new hole transport material with supplemented optoelectronic character. The pure and Y-doped CuO thin films are developed through a solid-state method at 200 °C and recognized as high performance p-channel inorganic thin-film transistors (TFTs). CuO is formed by oxidative decomposition of copper acetylacetonate, yielding 100 nm thick and conductive (40.9 S cm-1 ) compact films with a band gap of 2.47 eV and charge carrier density of ∼1.44×1019  cm-3 . Yttrium doping generates denser films, Cu2 Y2 O5 phase in the lattice, with a wide band gap of 2.63 eV. The electrical conductivity increases nine-fold on 2 % Y addition to CuO, and the carrier density increases to 2.97×1021  cm-3 , the highest reported so far. The TFT devices perform remarkably with high field-effect mobility (µsat ) of 3.45 cm2 V-1 s-1 and 5.3 cm2 V-1 s-1 , and considerably high current-on/off ratios of 0.11×104 and 9.21×104 , for CuO and Y-CuO films, respectively (at -1 V operating voltage). A very small width hysteresis, 0.01 V for CuO and 1.92 V for 1 % Y-CuO, depict good bias stability. Both the devices work in enhancement mode with stable output characteristics for multiple forward sweeps (5 to -60 V) at -1Vg .

20.
BMC Infect Dis ; 20(1): 911, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33261582

RESUMO

BACKGROUND: Human Sapoviruses (SaVs) has been reported as one of the causative agents of acute gastroenteritis (AGE) worldwide. An outbreak of SaVs affected 482 primary school students during spring activities from February 24 to March 11, 2019 in Shenzhen City, China. Our study was aimed at determining the epidemiology of the outbreak, investigating its origins, and making a clear identification of the SaVs genetic diversity. METHODS: Epidemiological investigation was conducted for this AGE outbreak. Stool samples were collected for laboratory tests of causative agents. Real-time reverse-transcription polymerase chain reaction (rRT-PCR) and conventional RT-PCR were used for detecting and genotyping of SaVs. The nearly complete genome of GII.8 SaV strains were amplified and sequenced by using several primer sets designed in this study. Phylogenetic analysis was performed to characterize the genome of GII.8 SaV strains. RESULTS: The single factor analysis showed that the students who were less than 1.5 m away from the vomitus in classroom or playgroundwere susceptible (P < 0.05). Seven of 11 fecal samples from patients were positive for GII.8 SaV genotype. In this study, we obtained the genome sequence of a SaV GII.8 strain Hu/SaV/2019008Shenzhen/2019 /CHN (SZ08) and comprehensively analyzed the genetic diversity. The phylogenetic analysis showed that the GII.8 strain SZ08 formed an independent branch and became a novel variant of GII.8 genotype. Strain SZ08 harbored 11 specific amino acid variations compared with cluster A-D in full-length VP1. CONCLUSIONS: This study identified SaVs as the causative agents for the AGE outbreak. Strain Hu SZ08 was clustered as independent branch and there was no recombination occurred in this strain SZ08. Further, it might become the predominant strain in diarrhea cases in the near future. Constant surveillance is required to monitor the emerging variants which will improve our knowledge of the evolution of SaVs among humans.


Assuntos
Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/transmissão , Surtos de Doenças , Gastroenterite/epidemiologia , Genótipo , Sapovirus/genética , Vômito/virologia , Adolescente , Sequência de Aminoácidos , Sequência de Bases , Infecções por Caliciviridae/virologia , Criança , China/epidemiologia , Diarreia/virologia , Fezes/virologia , Feminino , Gastroenterite/virologia , Variação Genética , Genoma Bacteriano/genética , Humanos , Masculino , Filogenia , Fatores de Risco
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