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1.
RSC Adv ; 13(38): 26995-27005, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37692350

RESUMO

Iron oxides with advanced functional properties show great potential for applications in the fields of water splitting, drug delivery, sensors, batteries and supercapacitors. However, it is challenging to develop a simple and efficient strategy for fabricating patterned iron oxide based electrodes for supercapacitor applications. Herein, a facile, simple, scalable, binder-free, surfactant-free and conductive additive-free electric discharge rusting (EDR) technique is proposed to directly synthesize Fe1-xO oxide layer on a pure iron substrate. This new EDR strategy is successfully adopted to fabricate Fe-Fe1-xO integrative patterned electrodes and coplanar microsupercapacitors (CMSC) in one step. The CMSC devices with different geometries could be directly patterned by EDR, which is automatically controlled by a computer numerical control system. The fabricated Fe-Fe1-xO based 3D 2F-CMSC exhibits a maximum areal specific capacitance of 112.4 mF cm-2. Another important finding is the fabrication of 3D 2F-CMSC devices, which show good capacitive behavior at an ultra high scanning rate of 20 000 mV s-1. The results prove that EDR is a low-cost and versatile strategy for the scalable fabrication of high-performance patterned supercapacitor integrative electrodes and devices. Furthermore, it is a versatile technique which shows a great potential for development of next generation microelectronic devices, such as microbatteries and microsensors.

2.
PLoS Pathog ; 19(5): e1011384, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37196026

RESUMO

Malayan pangolin SARS-CoV-2-related coronavirus (SARSr-CoV-2) is closely related to SARS-CoV-2. However, little is known about its pathogenicity in pangolins. Using CT scans we show that SARSr-CoV-2 positive Malayan pangolins are characterized by bilateral ground-glass opacities in lungs in a similar manner to COVID-19 patients. Histological examination and blood gas tests are indicative of dyspnea. SARSr-CoV-2 infected multiple organs in pangolins, with the lungs the major target, and histological expression data revealed that ACE2 and TMPRSS2 were co-expressed with viral RNA. Transcriptome analysis indicated that virus-positive pangolins were likely to have inadequate interferon responses, with relative greater cytokine and chemokine activity in the lung and spleen. Notably, both viral RNA and viral proteins were detected in three pangolin fetuses, providing initial evidence for vertical virus transmission. In sum, our study outlines the biological framework of SARSr-CoV-2 in pangolins, revealing striking similarities to COVID-19 in humans.


Assuntos
COVID-19 , Quirópteros , Animais , Humanos , Pangolins/genética , SARS-CoV-2/genética , Virulência , Filogenia , RNA Viral , Tropismo
3.
Front Physiol ; 14: 1041622, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36875026

RESUMO

Objective: This study's purpose was to investigate the effects of different intensities of physical activity on cardiovascular metabolism in obese children and adolescents based on an isochronous replacement model. Methods: A total of 196 obese children and adolescents (mean age, 13.44 ± 1.71 years) who met the inclusion criteria and attended a summer camp from July 2019 to August 2021 were recruited for this study, and all subjects wore a GT3X + triaxial motion accelerometer uniformly around the waist to record physical activity levels. We collected the subjects' height, weight, and cardiovascular risk factors such as waist circumference, hip circumference, fasting lipids, blood pressure, fasting insulin, and fasting glucose before and after 4 weeks of camp and constructed cardiometabolic risk score (CMR-z). We analyzed the effects of different intensities of physical activity on cardiovascular metabolism in obese children using isotemporal substitution model (ISM). Results: After 4 weeks, cardiovascular risk factors such as body weight, waist circumference, triglyceride, and total cholesterol were reduced in adolescents with obesity (p <0.01), and CMR-z was also reduced (p <0.01). ISM analysis revealed that all sedentary behavior (SB) replacement with 10 min of light physical activity (LPA) reduced CMR-z [ß = -0.10, 95% CI (-0.20, -0.01)]; 10-min of moderate physical activity (MPA) replacement of SB reduced CMR-z [ß = -0.32, 95% CI (-0.63, -0.01)]; 10-min of vigorous physical activity (VPA) replacement of SB reduced CMR-z [ß = -0.39, 95% CI (-0.66, -0.12)]. Conclusion: Replacement of SB with 10 min of LPA, MPA, and VPA were all effective in improving cardiovascular risk health, respectively, but MPA or VPA was more effective.

4.
ACS Omega ; 8(51): 48662-48672, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38162774

RESUMO

In this study, upconversion nanoparticles (UCNPs) with a flower-like morphology were prepared using a urea coprecipitation method. A ternary photocatalyst was first prepared using a solvothermal method involving the use of titanium oxide (TiO2), hexagonal boron nitride (h-BN), and UCNPs (Y2O3, Yb3+, and Tm3+) as raw materials. The surface morphology, crystal structure, and functional groups of these materials were then characterized and analyzed through scanning electron microscopy, transmission electron microscopy, X-ray diffraction analysis, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, ultraviolet-visible spectrophotometry, and other techniques. Photocatalytic experiments were also conducted to investigate the effects of different catalyst types, raw material doping ratios, pH values, and catalyst quantities on the photocatalytic degradation of rhodamine B (RhB). The results indicated that doping with h-BN and UCNPs reduced the band gap width of RhB, increased its light absorption rate, and decreased the recombination rate of its photogenerated electrons and holes so that the photocatalytic degradation effect reached 100% within 2 h. After five experimental cycles, the 30% UC-BN-Ti photocatalyst remained highly durable and stable. To investigate the effects of different trapping agents on the degradation of RhB, benzoquinone, isopropanol, and ethylenediaminetetraacetic acid disodium salt were used as free-radical-capturing agents. The results indicated that •O2- was the primary active species in the degradation process. Finally, the pathway and mechanism of the degradation of RhB through ternary composite photocatalysis were identified.

6.
Nature ; 583(7815): 286-289, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32380510

RESUMO

The current outbreak of coronavirus disease-2019 (COVID-19) poses unprecedented challenges to global health1. The new coronavirus responsible for this outbreak-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-shares high sequence identity to SARS-CoV and a bat coronavirus, RaTG132. Although bats may be the reservoir host for a variety of coronaviruses3,4, it remains unknown whether SARS-CoV-2 has additional host species. Here we show that a coronavirus, which we name pangolin-CoV, isolated from a Malayan pangolin has 100%, 98.6%, 97.8% and 90.7% amino acid identity with SARS-CoV-2 in the E, M, N and S proteins, respectively. In particular, the receptor-binding domain of the S protein of pangolin-CoV is almost identical to that of SARS-CoV-2, with one difference in a noncritical amino acid. Our comparative genomic analysis suggests that SARS-CoV-2 may have originated in the recombination of a virus similar to pangolin-CoV with one similar to RaTG13. Pangolin-CoV was detected in 17 out of the 25 Malayan pangolins that we analysed. Infected pangolins showed clinical signs and histological changes, and circulating antibodies against pangolin-CoV reacted with the S protein of SARS-CoV-2. The isolation of a coronavirus from pangolins that is closely related to SARS-CoV-2 suggests that these animals have the potential to act as an intermediate host of SARS-CoV-2. This newly identified coronavirus from pangolins-the most-trafficked mammal in the illegal wildlife trade-could represent a future threat to public health if wildlife trade is not effectively controlled.


Assuntos
Betacoronavirus/genética , Betacoronavirus/isolamento & purificação , Eutérios/virologia , Evolução Molecular , Genoma Viral/genética , Homologia de Sequência do Ácido Nucleico , Animais , Betacoronavirus/classificação , COVID-19 , China , Quirópteros/virologia , Chlorocebus aethiops , Proteínas do Envelope de Coronavírus , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/patologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Proteínas M de Coronavírus , Proteínas do Nucleocapsídeo de Coronavírus , Reservatórios de Doenças/virologia , Genômica , Especificidade de Hospedeiro , Humanos , Pulmão/patologia , Pulmão/virologia , Malásia , Proteínas do Nucleocapsídeo/genética , Pandemias , Fosfoproteínas , Filogenia , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Reação em Cadeia da Polimerase , Recombinação Genética , SARS-CoV-2 , Alinhamento de Sequência , Análise de Sequência de RNA , Glicoproteína da Espícula de Coronavírus/genética , Células Vero , Proteínas do Envelope Viral/genética , Proteínas da Matriz Viral/genética , Zoonoses/transmissão , Zoonoses/virologia
7.
Aging (Albany NY) ; 8(12): 3356-3374, 2016 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-27992859

RESUMO

While cellular senescence is a critical mechanism to prevent malignant transformation of potentially mutated cells, persistence of senescent cells can also promote cancer and aging phenotypes. NonO/p54nrb and PSF are multifunctional hnRNPs typically found as a complex exclusively within the nuclei of all mammalian cells. We demonstrate here that either increase or reduction of expression of either factor results in cellular senescence. Coincident with this, we observe expulsion of NonO and PSF-containing nuclear paraspeckles and posttranslational modification at G2/M. That senescence is mediated most robustly by overexpression of a cytoplasmic C-truncated form of NonO further indicated that translocation of NonO and PSF from the nucleus is critical to senescence induction. Modulation of NonO and PSF expression just prior to or coincident with senescence induction disrupts the normally heterodimeric NonO-PSF nuclear complex resulting in a dramatic shift in stoichiometry to heterotetramers and monomer with highest accumulation within the cytoplasm. This is accompanied by prototypic cell cycle checkpoint activation and chromatin condensation. These observations identify yet another role for these multifunctional factors and provide a hitherto unprecedented mechanism for cellular senescence and nuclear-cytoplasmic trafficking.


Assuntos
Senescência Celular/fisiologia , Proteínas Associadas à Matriz Nuclear/metabolismo , Fatores de Transcrição de Octâmero/metabolismo , Fator de Processamento Associado a PTB/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Linhagem Celular , Citoplasma/fisiologia , Dano ao DNA , Proteínas de Ligação a DNA , Regulação da Expressão Gênica , Humanos , Mitose , Mutação , Proteínas Associadas à Matriz Nuclear/genética , Fatores de Transcrição de Octâmero/genética , Fator de Processamento Associado a PTB/genética , Plasmídeos , Processamento de Proteína Pós-Traducional , Proteínas de Ligação a RNA/genética , Encurtamento do Telômero , Transformação Genética , Regulação para Cima
8.
Biotechnol Bioeng ; 99(1): 146-54, 2008 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17546686

RESUMO

The direct correlation between levels of heat shock protein expression and efficiency of its tissue protection function motivates this study of how thermal doses can be used for an optimal stress protocol design. Heat shock protein 70 (HSP70) expression kinetics were visualized continuously in cultured bovine aortic endothelial cells (BAECs) on a microscope heating stage using green fluorescent protein (GFP) as a reporter. BAECs were transfected with a DNA vector, HSP(p)-HSP70-GFP which expresses an HSP70-GFP fusion protein under control of the HSP70 promoter. Expression levels were validated by western blot analysis. Transfected cells were heated on a controlled temperature microscope stage at 42 degrees C for a defined period, then shifted to 37 degrees C for varied post-heating times. The expression of HSP70-GFP and its sub-cellular localization were visualized via fluorescence microscopy. The progressive expression kinetics were measured by quantitative analysis of serial fluorescence images captured during heating protocols from 1 to 2 h and post-heating times from 0 to 20 h. The results show two sequential peaks in HSP70 expression at approximately 3 and 12 h post-heat shock. A progressive translocation of HSP70 from the cytoplasm to the nucleus was observed from 6 to 16 h. We conclude that we have successfully combined molecular cloning and optical imaging to study HSP70 expression kinetics. The kinetic profile for HSP70-GFP fusion protein is consistent with the endogenous HSP70. Furthermore, information on dynamic intracellular translocation of HSP70 was extracted from the same experimental data.


Assuntos
Células Endoteliais/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Microscopia de Fluorescência/métodos , Frações Subcelulares/metabolismo , Animais , Bovinos , Células Cultivadas , Células Endoteliais/ultraestrutura , Proteínas de Fluorescência Verde/metabolismo , Calefação/métodos , Cinética , Taxa de Depuração Metabólica , Perfusão , Proteínas Recombinantes de Fusão/metabolismo , Frações Subcelulares/ultraestrutura , Temperatura
9.
RNA ; 8(9): 1102-11, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12358429

RESUMO

The carboxyl-terminal domain (CTD) of the largest subunit of eukaryotic RNA polymerase II (pol II) plays an important role in promoting steps of pre-mRNA processing. To identify proteins in human cells that bind to the CTD and that could mediate its functions in pre-mRNA processing, we used the mouse CTD expressed in bacterial cells in affinity chromatography experiments. Two proteins present in HeLa cell extract, the splicing and transcription-associated factors, PSF and p54nrb/NonO, bound specifically and could be purified to virtual homogeneity by chromatography on immobilized CTD matrices. Both hypo- and hyperphosphorylated CTD matrices bound these proteins with similar selectivity. PSF and p54nrb/NonO also copurified with a holoenzyme form of pol II containing hypophosphorylated CTD and could be coimmunoprecipitated with antibodies specific for this and the hyperphosphorylated form of pol II. That PSF and p54nrb/NonO promoted the binding of RNA to immobilized CTD matrices suggested these proteins can interact with the CTD and RNA simultaneously. PSF and p54nrb/NonO may therefore provide a direct physical link between the pol II CTD and pre-mRNA processing components, at both the initiation and elongation phases of transcription.


Assuntos
Proteínas Associadas à Matriz Nuclear , Proteínas Nucleares/metabolismo , RNA Polimerase II/metabolismo , Proteínas de Ligação a RNA/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Proteínas de Ligação a DNA , Células HeLa , Holoenzimas/química , Holoenzimas/metabolismo , Humanos , Técnicas In Vitro , Camundongos , Dados de Sequência Molecular , Proteínas Nucleares/química , Proteínas Nucleares/genética , Fatores de Transcrição de Octâmero , Fator de Processamento Associado a PTB , Fosforilação , Estrutura Terciária de Proteína , RNA Polimerase II/química , RNA Polimerase II/genética , Precursores de RNA/metabolismo , Processamento Pós-Transcricional do RNA , Splicing de RNA , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transcrição Gênica
10.
Artigo em Inglês | MEDLINE | ID: mdl-12114964

RESUMO

The effect of high hydrostatic pressure on the activities of type II restriction enzymes HindIII and XbaI in digesting plasmid pSPORT1 was studied. The endonuclease activity of HindIII and XbaI at 37 degrees were gradually inhibited by increasing pressure and completely inhibited at 200 and 180 MPa, respectively. No obvious irreversible effect was observed for HindIII after suffering high pressure, while a considerable irreversible inactivation was observed for XbaI. The standard molar volume changes for HindIII and XbaI estimated from the inhibition of endonuclease activity at different pressures were 213 and 103 ml/mol, respectively. It was also concluded that pressurization did not change the substrate sequence specificity of both HindIII and XbaI.

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