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1.
Opt Lett ; 49(19): 5407-5410, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39352968

RESUMO

Tunable metasurfaces offer a promising avenue for dynamically modulating terahertz waves. Phase-change materials are crucial in this dynamic modulation, enabling precise and reversible control over the electromagnetic properties of the metasurfaces. In this study, we designed and experimentally fabricated a tunable lattice-induced transparent metasurface. This metasurface comprises two gold rod resonators exhibiting different periodic distributions, each supporting an electric dipole resonance at 2.03 THz and a surface lattice resonance at 1.51 THz, respectively. By combining these structures, we realize lattice-induced transparency. Simulation results show that the phase change of Ge2Sb2Te5 modulates these resonances, with the crystalline state significantly weakening their resonance strength intensity. The maximum modulation depth of the lattice-induced transparency peak can reach 44.4%. Experimental results of laser-induced GST phase changes confirm a modulation depth of 42.4%. This innovative metasurface design holds promise for applications in terahertz communication systems.

2.
BMC Cancer ; 24(1): 947, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39095785

RESUMO

BACKGROUND: Although immunotherapy shows tremendous potential in the treatment of bladder cancer (BLCA), the overall prognosis and response rates to immunotherapy in BLCA remain suboptimal. METHODS: We performed an extensive evaluation of glycosyltransferase expression patterns in BLCA patients by analyzing 210 glycosyltransferase-related genes. Subsequently, we established correlations between these glycosyltransferase patterns, prognosis, and tumor microenvironment (TME) phenotypes. To offer personalized patient assessments, we developed a glycosyltransferase risk score that accurately predicts prognosis, TME phenotypes, and molecular subtypes. Importantly, we developed a RNA-seq cohort, named Xiangya cohort, to validate our results. RESULTS: Two distinct patterns of glycosyltransferase expression were identified, corresponding to inflamed and noninflamed TME phenotypes, and demonstrated the potential to predict prognosis. We developed and validated a comprehensive risk score that accurately predicted individual patient prognosis in the TCGA-BLCA cohort. Additionally, we constructed a nomogram that integrated the risk score with several key clinical factors. Importantly, this risk score was successfully validated in external cohorts, including the Xiangya cohort and GSE48075. Furthermore, we discovered a positive correlation between this risk score and tumor-infiltrating lymphocytes in both the TCGA-BLCA and Xiangya cohorts, suggesting that patients with a higher risk score exhibited an inflamed TME phenotype and were more responsive to immunotherapy. Finally, we observed that the high and low risk score groups were consistent with the luminal and basal subtypes of BLCA, respectively, providing further validation of the risk score's role in the TME in terms of molecular subtypes. CONCLUSIONS: Glycosyltransferase patterns exhibit distinct TME phenotypes in BLCA. Our comprehensive risk score provides a promising approach for prognostic prediction and assessment of immunotherapy efficacy, offering valuable guidance for precision medicine.


Assuntos
Glicosiltransferases , Imunoterapia , Nomogramas , Fenótipo , Microambiente Tumoral , Neoplasias da Bexiga Urinária , Humanos , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/terapia , Neoplasias da Bexiga Urinária/imunologia , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/mortalidade , Microambiente Tumoral/imunologia , Microambiente Tumoral/genética , Prognóstico , Imunoterapia/métodos , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Masculino , Feminino , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Biomarcadores Tumorais/genética , Pessoa de Meia-Idade , Medição de Risco , Idoso , Regulação Neoplásica da Expressão Gênica , Fatores de Risco
3.
J Org Chem ; 89(17): 12255-12262, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39151121

RESUMO

An efficient p-TsOH-mediated insertion of sodium thiocyanate into trifluoromethylimidoyl sulfoxonium ylides has been reported, affording annulated N-aryl-4-trifluoromethylthiazol-2-amines in 42-84% yields in a one-pot manner. This protocol encompasses a variety of trifluoromethylimidoyl sulfoxonium ylides with thiocyanate serving as the source of the "S-C═N" moiety of the thiazole ring. The versatile transformations of the resulting pharmacologically important N-aryl-4-trifluoromethylthiazol-2-amines were also demonstrated.

4.
Fish Shellfish Immunol ; 153: 109805, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39102972

RESUMO

The production of type I interferon is tightly regulated to prevent excessive immune activation. However, the role of selective autophagy receptor SQSTM1 in this regulation in teleost remains unknown. In this study, we cloned the triploid fish SQSTM1 (3nSQSTM1), which comprises 1371 nucleotides, encoding 457 amino acids. qRT-PCR data revealed that the transcript levels of SQSTM1 in triploid fish were increased both in vivo and in vitro following spring viraemia of carp virus (SVCV) infection. Immunofluorescence analysis confirmed that 3nSQSTM1 was mainly distributed in the cytoplasm. Luciferase reporter assay results showed that 3nSQSTM1 significantly blocked the activation of interferon promoters induced by 3nMDA5, 3nMAVS, 3nTBK1, and 3nIRF7. Co-immunoprecipitation assays further confirmed that 3nSQSTM1 could interact with both 3nTBK1 and 3nIRF7. Moreover, upon co-transfection, 3nSQSTM1 significantly inhibited the antiviral activity mediated by TBK1 and IRF7. Mechanistically, 3nSQSTM1 decreased the TBK1 phosphorylation and its interaction with 3nIRF7, thereby suppressing the subsequent antiviral response. Notably, we discovered that 3nSQSTM1 also interacted with SVCV N and P proteins, and these viral proteins may exploit 3nSQSTM1 to further limit the host's antiviral innate immune responses. In conclusion, our study demonstrates that 3nSQSTM1 plays a pivotal role in negatively regulating the interferon signaling pathway by targeting 3nTBK1 and 3nIRF7.


Assuntos
Carpas , Doenças dos Peixes , Proteínas de Peixes , Imunidade Inata , Fator Regulador 7 de Interferon , Infecções por Rhabdoviridae , Rhabdoviridae , Animais , Imunidade Inata/genética , Doenças dos Peixes/imunologia , Doenças dos Peixes/virologia , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Fator Regulador 7 de Interferon/genética , Fator Regulador 7 de Interferon/imunologia , Rhabdoviridae/fisiologia , Infecções por Rhabdoviridae/imunologia , Infecções por Rhabdoviridae/veterinária , Carpas/imunologia , Carpas/genética , Proteína Sequestossoma-1/genética , Proteína Sequestossoma-1/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/imunologia , Proteínas Serina-Treonina Quinases/metabolismo , Regulação da Expressão Gênica/imunologia , Transdução de Sinais/imunologia , Triploidia , Filogenia , Sequência de Aminoácidos , Alinhamento de Sequência/veterinária , Perfilação da Expressão Gênica/veterinária
5.
Fish Shellfish Immunol ; 146: 109426, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38316349

RESUMO

Glutathione S-transferase P1 (GSTP1), the most ubiquitous member of the GST superfamily, plays vital roles in the detoxification, antioxidant defense, and modulation of inflammatory responses. However, limited studies have been conducted on the function of GSTP1 in antiviral innate immunity. In this study, we have cloned the homolog of GSTP1 in triploid hybrid crucian carp (3nGSTP1) and investigated its regulatory role in the interferon signaling pathway. The open reading frame of 3nGSTP1 is composed of 627 nucleotides, encoding 209 amino acids. In response to spring viremia of carp virus (SVCV) infection, the mRNA level of 3nGSTP1 was up-regulated in the liver, kidney, and caudal fin cell lines (3 nF C) of triploid fish. The knockdown of 3nGSTP1 in 3 nF C improved host cell's antiviral capacity and attenuated SVCV replication. Additionally, overexpression of 3nGSTP1 inhibited the activation of IFN promoters induced by SVCV infection, poly (I:C) stimulation, or the RLR signaling factors. The co-immunoprecipitation assays further revealed that 3nGSTP1 interacts with 3nMAVS. In addition, 3nGSTP1 dose-dependently inhibited 3nMAVS-mediated antiviral activity and reduced 3nMAVS protein level. Mechanistically, 3nGSTP1 promoted ubiquitin-proteasome degradation of MAVS by promoting its K48-linked polyubiquitination. To conclude, our results indicate that GSTP1 acts as a novel inhibitor of MAVS, which negatively regulates the IFN signaling.


Assuntos
Carpas , Doenças dos Peixes , Infecções por Rhabdoviridae , Rhabdoviridae , Animais , Triploidia , Transdução de Sinais , Rhabdoviridae/fisiologia , Infecções por Rhabdoviridae/veterinária , Imunidade Inata/genética , Poli I-C/farmacologia , Antivirais
6.
Org Biomol Chem ; 22(31): 6246-6276, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39041070

RESUMO

Trifluoromethylated heterocyclic compounds have played an increasingly significant role in pharmaceuticals, agrochemicals, and materials. This is because the introduction of trifluoromethyl could enhance the lipophilicity, metabolic stability, and pharmacokinetic properties of heterocyclic drug molecules. Therefore, the synthesis of trifluoromethylated heterocyclics has become a major subject of research. The construction of trifluoromethylated heterocyclics via the annulation of trifluoromethyl building blocks with suitable partners has been proved to be a powerful strategy. In this review, we systematically summarize and discuss recent advances in the preparation of trifluoromethyl-containing heterocyclics via trifluoromethyl building block strategies over the period from 2019 to the present.

7.
Environ Sci Technol ; 58(40): 17990-17998, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39324609

RESUMO

Antibiotic resistance genes (ARGs) as emerging environmental contaminants exacerbate the risk of spreading antibiotic resistance. Natural organic matter (NOM) is ubiquitous in aquatic environments and plays a crucial role in biogeochemical cycles. However, its impact on the dissemination of extracellular antibiotic resistance genes (eARGs) under sunlight exposure remains elusive. This study reveals that environmentally relevant levels of NOM (0.1-20 mg/L) can significantly enhance the natural transformation frequency of the model bacterium Acinetobacter baylyi ADP1 by up to 7.6-fold under simulated sunlight. Similarly, this enhancement was consistently observed in natural water and wastewater systems. Further mechanism analysis revealed that reactive oxygen species (ROS) generated by NOM under sunlight irradiation, primarily singlet oxygen and hydroxyl radicals, play a crucial role in this process. These ROS induce intracellular oxidative stress and elevated cellular membrane permeability, thereby indirectly boosting ATP production and enhancing cell competence of extracellular DNA uptake and integration. Our findings highlight a previously underestimated role of natural factors in the dissemination of eARGs within aquatic ecosystems and deepen our understanding of the complex interplay between NOM, sunlight, and microbes in environmental water bodies. This underscores the importance of developing comprehensive strategies to mitigate the spread of antibiotic resistance in aquatic environments.


Assuntos
Resistência Microbiana a Medicamentos , Luz Solar , Resistência Microbiana a Medicamentos/genética , Antibacterianos/farmacologia , Espécies Reativas de Oxigênio/metabolismo
8.
Environ Res ; 256: 119252, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38815716

RESUMO

Bio-ingestion of microplastics poses a global threat to ecosystems, yet studies within nature reserves, crucial habitats for birds, remain scarce despite the well-documented ingestion of microplastics by avian species. Located in Jiangsu Province, China, the Yancheng Wetland Rare Birds Nature Reserve is home to diverse bird species, including many rare ones. This study aimed to assess the abundance and characteristics of microplastics in common bird species within the reserve, investigate microplastic enrichment across different species, and establish links between birds' habitat types and microplastic ingestion. Microplastics were extracted from the feces of 110 birds, with 84 particles identified from 37.27% of samples. Among 8 species studied, the average microplastic abundance ranged from 0.97 ± 0.47 to 43.43 ± 61.98 items per gram of feces, or 1.5 ± 0.87 to 3.4 ± 1.50 items per individual. The Swan goose (Anser cygnoides) exhibited the highest microplastic abundance per gram of feces, while the black-billed gull (Larus saundersi) had the highest abundance per individual. The predominant form of ingested microplastics among birds in the reserve was fibers, with polyethylene being the most common polymer type. Significant variations in plastic exposure were observed among species and between aquatic and terrestrial birds. This study represents the first quantitative assessment of microplastic concentrations in birds within the reserve, filling a crucial gap in research and providing insights for assessing microplastic pollution and guiding bird conservation efforts in aquatic and terrestrial environments.


Assuntos
Aves , Monitoramento Ambiental , Fezes , Microplásticos , Áreas Alagadas , Animais , China , Microplásticos/análise , Fezes/química , Poluentes Químicos da Água/análise , Conservação dos Recursos Naturais
9.
Sensors (Basel) ; 24(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38475080

RESUMO

The performance of a hemispherical resonant gyroscope (HRG) is directly affected by the sphericity error of the thin-walled spherical shell of the hemispherical shell resonator (HSR). In the production process of the HSRs, high-speed, high-accuracy, and high-robustness requirements are necessary for evaluating sphericity errors. We designed a sphericity error evaluation method based on the minimum zone criterion with an adaptive number of subpopulations. The method utilizes the global optimal solution and the subpopulations' optimal solution to guide the search, initializes the subpopulations through clustering, and dynamically eliminates inferior subpopulations. Simulation experiments demonstrate that the algorithm exhibits excellent evaluation accuracy when processing simulation datasets with different sphericity errors, radii, and numbers of sampling points. The uncertainty of the results reached the order of 10-9 mm. When processing up to 6000 simulation datasets, the algorithm's solution deviation from the ideal sphericity error remained around -3 × 10-9 mm. And the sphericity error evaluation was completed within 1 s on average. Additionally, comparison experiments further confirmed the evaluation accuracy of the algorithm. In the HSR sample measurement experiments, our algorithm improved the sphericity error assessment accuracy of the HSR's inner and outer contour sampling datasets by 17% and 4%, compared with the results given by the coordinate measuring machine. The experiment results demonstrated that the algorithm meets the requirements of sphericity error assessment in the manufacturing process of the HSRs and has the potential to be widely used in the future.

10.
Alzheimers Dement ; 20(10): 6984-6997, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39175425

RESUMO

INTRODUCTION: The paramagnetic iron, diamagnetic amyloid beta (Aß) plaques and their interaction are crucial in Alzheimer's disease (AD) pathogenesis, complicating non-invasive magnetic resonance imaging for prodromal AD detection. METHODS: We used a state-of-the-art sub-voxel quantitative susceptibility mapping method to simultaneously measure Aß and iron levels in post mortem human brains, validated by histology. Further transcriptomic analysis using Allen Human Brain Atlas elucidated the underlying biological processes. RESULTS: Regional increased paramagnetic and diamagnetic susceptibility were observed in medial prefrontal, medial parietal, and para-hippocampal cortices associated with iron deposition (R = 0.836, p = 0.003) and Aß accumulation (R = 0.853, p = 0.002) in AD brains. Higher levels of gene expression relating to cell cycle, post-translational protein modifications, and cellular response to stress were observed. DISCUSSION: These findings provide quantitative insights into the variable vulnerability of cortical regions to higher levels of Aß aggregation, iron overload, and subsequent neurodegeneration, indicating changes preceding clinical symptoms. HIGHLIGHTS: The vulnerability of distinct brain regions to amyloid beta (Aß) and iron accumulation varies. Histological validation was performed on stained sections of ex-vivo human brains. Regional variations in susceptibility were linked to gene expression profiles. Iron and Aß levels in ex-vivo brains were simultaneously quantified.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Encéfalo , Ferro , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Doença de Alzheimer/patologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/metabolismo , Autopsia , Encéfalo/patologia , Encéfalo/metabolismo , Ferro/metabolismo , Imageamento por Ressonância Magnética , Placa Amiloide/patologia , Placa Amiloide/metabolismo
11.
Int J Mol Sci ; 25(13)2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-39000546

RESUMO

Plants are often exposed to biotic or abiotic stress, which can seriously impede their growth and development. In recent years, researchers have focused especially on the study of plant responses to biotic and abiotic stress. As one of the most widely planted grapevine rootstocks, 'Beta' has been extensively proven to be highly resistant to stress. However, further research is needed to understand the mechanisms of abiotic stress in 'Beta' rootstocks. In this study, we isolated and cloned a novel WRKY transcription factor, VhWRKY44, from the 'Beta' rootstock. Subcellular localization analysis revealed that VhWRKY44 was a nuclear-localized protein. Tissue-specific expression analysis indicated that VhWRKY44 had higher expression levels in grape roots and mature leaves. Further research demonstrated that the expression level of VhWRKY44 in grape roots and mature leaves was highly induced by salt and cold treatment. Compared with the control, Arabidopsis plants overexpressing VhWRKY44 showed stronger resistance to salt and cold stress. The activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were significantly increased, and the contents of proline, malondialdehyde (MDA) and chlorophyll were changed considerably. In addition, significantly higher levels of stress-related genes were detected in the transgenic lines. The results indicated that VhWRKY44 was an important transcription factor in 'Beta' with excellent salt and cold tolerance, providing a new foundation for abiotic stress research.


Assuntos
Arabidopsis , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Plantas Geneticamente Modificadas , Fatores de Transcrição , Vitis , Arabidopsis/genética , Arabidopsis/metabolismo , Vitis/genética , Vitis/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Estresse Fisiológico/genética , Temperatura Baixa , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Tolerância ao Sal/genética , Folhas de Planta/metabolismo , Folhas de Planta/genética
12.
Angew Chem Int Ed Engl ; 63(41): e202409366, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-38979942

RESUMO

In this work, we describe an efficient and modular method for enantiodivergent accessing P(V)-stereogenic molecules by utilizing the catalytic atroposelective Catellani-type C-H arylation/desymmetric intramolecular N-arylation cascade reaction. The enantioselectivity of this protocol was proved to be tuned by the polarity of the solvent, thus providing a wide range of both chiral P(V)-stereogenic enantiomers in moderate to good yields with good to excellent enantiomeric excesses. Noteworthy is that the strategy developed herein represents an unprecedented example of solvent-dictated inversion of the enantioselectivity of P(V)-stereogenic compounds.

13.
Neuroimage ; 274: 120148, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37127191

RESUMO

The brain tissue phase contrast in MRI sequences reflects the spatial distributions of multiple substances, such as iron, myelin, calcium, and proteins. These substances with paramagnetic and diamagnetic susceptibilities often colocalize in one voxel in brain regions. Both opposing susceptibilities play vital roles in brain development and neurodegenerative diseases. Conventional QSM methods only provide voxel-averaged susceptibility value and cannot disentangle intravoxel susceptibilities with opposite signs. Advanced susceptibility imaging methods have been recently developed to distinguish the contributions of opposing susceptibility sources for QSM. The basic concept of separating paramagnetic and diamagnetic susceptibility proportions is to include the relaxation rate R2* with R2' in QSM. The magnitude decay kernel, describing the proportionality coefficient between R2' and susceptibility, is an essential reconstruction coefficient for QSM separation methods. In this study, we proposed a more comprehensive complex signal model that describes the relationship between 3D GRE signal and the contributions of paramagnetic and diamagnetic susceptibility to the frequency shift and R2* relaxation. The algorithm is implemented as a constrained minimization problem in which the voxel-wise magnitude decay kernel and sub-voxel susceptibilities are determined alternately in each iteration until convergence. The calculated voxel-wise magnitude decay kernel could realistically model the relationship between the R2' relaxation and the volume susceptibility. Thus, the proposed method effectively prevents the errors of the magnitude decay kernel from propagating to the final susceptibility separation reconstruction. Phantom studies, ex vivo macaque brain experiments, and in vivo human brain imaging studies were conducted to evaluate the ability of the proposed method to distinguish paramagnetic and diamagnetic susceptibility sources. The results demonstrate that the proposed method provides state-of-the-art performances for quantifying brain iron and myelin compared to previous QSM separation methods. Our results show that the proposed method has the potential to simultaneously quantify whole brain iron and myelin during brain development and aging. The proposed model was also deployed with multiple-orientation complex GRE data input measurements, resulting in high-quality QSM separation maps with more faithful tissue delineation between brain structures compared to those reconstructed by single-orientation QSM separation methods.


Assuntos
Mapeamento Encefálico , Encéfalo , Humanos , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Mapeamento Encefálico/métodos , Envelhecimento , Imageamento por Ressonância Magnética/métodos , Ferro/metabolismo
14.
Hum Brain Mapp ; 44(17): 5953-5971, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37721369

RESUMO

The evolution of magnetic susceptibility of the brain is mainly determined by myelin in white matter (WM) and iron deposition in deep gray matter (DGM). However, existing imaging techniques have limited abilities to simultaneously quantify the myelination and iron deposition within a voxel throughout brain development and aging. For instance, the temporal trajectories of iron in the brain WM and myelination in DGM have not been investigated during the aging process. This study aimed to map the age-related iron and myelin changes in the whole brain, encompassing myelin in DGM and iron deposition in WM, using a novel sub-voxel quantitative susceptibility mapping (QSM) method. To achieve this, a cohort of 494 healthy adults (18-80 years old) was studied. The sub-voxel QSM method was employed to obtain the paramagnetic and diamagnetic susceptibility based on the approximated R 2 ' map from acquired R 2 * map. The linear relationship between R 2 * and R 2 ' maps was established from the regression coefficients on a small cohort data acquired with both 3D gradient recalled echo data and R 2 mapping. Large cohort sub-voxel susceptibility maps were used to create longitudinal and age-specific atlases via group-wise registration. To explore the differential developmental trajectories in the DGM and WM, we employed nonlinear models including exponential and Poisson functions, along with generalized additive models. The constructed atlases reveal the iron accumulation in the posterior part of the putamen and the gradual myelination process in the globus pallidus with aging. Interestingly, the developmental trajectories show that the rate of myelination differs among various DGM regions. Furthermore, the process of myelin synthesis is paralleled by an associated pattern of iron accumulation in the primary WM fiber bundles. In summary, our study offers significant insights into the distinctive developmental trajectories of iron in the brain's WM and myelination/demyelination in the DGM in vivo. These findings highlight the potential of using sub-voxel QSM to uncover new perspectives in neuroscience and improve our understanding of whole-brain myelination and iron deposit processes across the lifespan.


Assuntos
Mapeamento Encefálico , Imageamento por Ressonância Magnética , Adulto , Humanos , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Ferro , Fenômenos Magnéticos , Substância Cinzenta
15.
J Neuroinflammation ; 20(1): 16, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36710351

RESUMO

Multiple sclerosis (MS) is an autoimmune demyelinating disease of the central nervous system (CNS). Anxiety and depression are the most common psychiatric comorbidities of MS, which seriously affect patients' quality of life, treatment compliance, and prognosis. However, current treatments for anxiety and depression in MS show low therapeutic efficacy and significant side effects. In the present study, we explored the therapeutic effects of a novel low-toxic anti-inflammatory drug, nanoparticulate magnesium hydride (MgH2), on mood disorders of MS. We observed that anxiety/depression-like behaviors in experimental autoimmune encephalomyelitis (EAE) mice were alleviated by MgH2 treatment. In addition, disease severity and inflammatory demyelination were also diminished. Furthermore, we confirmed the suppressive effect of MgH2 on depression in the acute restraint stress model. Mechanistically, MgH2 may play a therapeutic role by promoting microglial M2 polarization, inhibiting microglial M1 polarization, and reducing oxidative stress and mitochondrial damage. Therefore, nanoparticulate MgH2 may be a promising therapeutic drug for psychiatric comorbidities of MS.


Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Camundongos , Animais , Esclerose Múltipla/complicações , Esclerose Múltipla/tratamento farmacológico , Microglia/fisiologia , Depressão/tratamento farmacológico , Depressão/etiologia , Qualidade de Vida , Encefalomielite Autoimune Experimental/tratamento farmacológico , Estresse Oxidativo , Ansiedade/tratamento farmacológico , Ansiedade/etiologia , Camundongos Endogâmicos C57BL
16.
Opt Express ; 31(22): 37186-37196, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-38017853

RESUMO

Frequency-induced instability is widely present in nematic liquid crystals (LCs), which poses a problem in improving liquid-crystal-based phase-shift devices driven by alternating currents. Herein, the Fréedericksz transition of thick nematic LCs was investigated under alternating electric fields to reveal the suppression of frequency-induced instability in the low frequency range. By extending the Frank-Leslie equation to the AC-driven case, the response of the LC was numerically calculated, and the frequency threshold for suppressing the driven instability was estimated in conjunction with the perturbation method. Experimentally, the frequency suppression of LC fluctuations was verified by using applied electric fields. In addition, the root-mean-square-error of the refractive index was measured to be less than 2 × 10-5, which excludes the convective instability-generating domains in devices. It was revealed that the fabricated thick LC phase shifters provided a phase shift of more than 360° at 2 THz and can be used in the terahertz band. It was observed that the electrically driven phase-shift characteristics were in accordance with the theoretical results as the threshold frequency condition was satisfied. This work provides an experimental and theoretical reference for improving modulation performance and enhancing the characterization of AC-driven LC-based phase-shift devices.

17.
Glob Chang Biol ; 29(16): 4511-4529, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37231532

RESUMO

Marine phytoplankton fuel the oceanic biotic chain, determine the carbon sequestration levels, and are crucial for the global carbon cycle and climate change. In the present study, we show a near-two-decadal (2002-2022) spatiotemporal distribution of global phytoplankton abundance, proxy as dominant phytoplankton taxonomic groups (PTGs), with a newly developed remote sensing model. Globally, six chief PTGs, namely chlorophytes (~26%), diatoms (~24%), haptophytes (~15%), cryptophytes (~10%), cyanobacteria (~8%), and dinoflagellates (~3%), explain most of the variation (~86%) in phytoplankton assemblages. Spatially, diatoms generally dominate high latitudes, marginal seas, and coastal upwelling zones, whereas chlorophytes and haptophytes control the open oceans. Satellite observations reveal a gentle multi-annual trend of the PTGs in the major oceans, indicative of roughly "unchanged" conditions on the total biomass or compositions of the phytoplankton community. Jointly, "changed" status applies to a short-term (seasonal) timescale: (1) Fluctuations of PTGs exhibit different amplitudes among different subregions, together with a general rule-more intense vibration in the Northern Hemisphere and polar oceans than other zones; (2) diatoms and haptophytes vary more dramatically than other PTGs in a global-scale scope. These findings provide a clear picture of the global phytoplankton community composition and can improve our understanding of their state and further analysis of marine biological processes.


Assuntos
Cianobactérias , Diatomáceas , Dinoflagellida , Fitoplâncton , Oceanos e Mares
18.
Environ Sci Technol ; 57(51): 21835-21845, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38085064

RESUMO

The persistence of extracellular antibiotic resistance genes (ARGs) in aquatic environments has attracted increasing attention due to their potential threat to public health and the environment. However, the fate of extracellular ARGs in receiving water remains largely unknown. This study investigated the influence of hematite nanoparticles, a widespread natural mineral, on the photodegradation of extracellular ARGs in river water. Results showed that under exposure to visible light, hematite nanoparticles, at environmental concentrations, resulted in a 3-5 orders of magnitude reduction in extracellular ARGs. This photodegradation of extracellular ARGs is shown to be facet-dependent; the (001) facet of hematite demonstrates a higher removal rate than that of the (100) facet, which is ascribed to its enhanced adsorption capability and higher hydroxyl radical (•OH) production. Density functional theory (DFT) calculations corroborate this finding, indicating elevated iron density, larger adsorption energy, and lower energy barrier of •OH formation on the (001) facet, providing more active sites and •OH generation for extracellular ARG interaction. Gel electrophoresis and atomic force microscopy analyses further confirm that the (001) facet causes more substantial damage to extracellular ARGs than the (100) facet. These findings pave the way for predicting the photodegradation efficiency of hematite nanoparticles with varied facets, thereby shedding light on the inherent self-purification capacity for extracellular ARGs in both natural and engineered aquatic environments.


Assuntos
Antibacterianos , Águas Residuárias , Antibacterianos/farmacologia , Genes Bacterianos , Água , Resistência Microbiana a Medicamentos/genética , Nanopartículas Magnéticas de Óxido de Ferro
19.
Ren Fail ; 45(1): 2190815, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37051665

RESUMO

Excessive daytime sleepiness (EDS) is associated with quality of life and all-cause mortality in the end-stage renal disease population. This study aims to identify biomarkers and reveal the underlying mechanisms of EDS in peritoneal dialysis (PD) patients. A total of 48 nondiabetic continuous ambulatory peritoneal dialysis patients were assigned to the EDS group and the non-EDS group according to the Epworth Sleepiness Scale (ESS). Ultra-high-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UHPLC-Q-TOF/MS) was used to identify the differential metabolites. Twenty-seven (male/female, 15/12; age, 60.1 ± 16.2 years) PD patients with ESS ≥ 10 were assigned to the EDS group, while twenty-one (male/female, 13/8; age, 57.9 ± 10.1 years) PD patients with ESS < 10 were defined as the non-EDS group. With UHPLC-Q-TOF/MS, 39 metabolites with significant differences between the two groups were found, 9 of which had good correlations with disease severity and were further classified into amino acid, lipid and organic acid metabolism. A total of 103 overlapping target proteins of the differential metabolites and EDS were found. Then, the EDS-metabolite-target network and the protein-protein interaction network were constructed. The metabolomics approach integrated with network pharmacology provides new insights into the early diagnosis and mechanisms of EDS in PD patients.


Assuntos
Distúrbios do Sono por Sonolência Excessiva , Falência Renal Crônica , Diálise Peritoneal Ambulatorial Contínua , Diálise Peritoneal , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Qualidade de Vida , Diálise Peritoneal/efeitos adversos , Diálise Peritoneal/métodos , Diálise Peritoneal Ambulatorial Contínua/efeitos adversos , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Distúrbios do Sono por Sonolência Excessiva/etiologia , Distúrbios do Sono por Sonolência Excessiva/diagnóstico , Distúrbios do Sono por Sonolência Excessiva/epidemiologia
20.
Int J Mol Sci ; 24(13)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37445921

RESUMO

In viticulture, the highly resistant rootstock 'Beta' is widely used in Chinese grape production to avoid the effects of soil salinization and drought on grape growth. However, the mechanism of high resistance to abiotic stress in the 'Beta' rootstock is not clear. In this study, we demonstrated that VhMYB2 as a transcription factor made a significant contribution to salinity and drought stress, which was isolated from the 'Beta' rootstock. The coding sequence of the VhMYB2 gene was 858 bp, encoding 285 amino acids. The subcellular localization of VhMYB2 was located in the nucleus of tobacco epidermal cells. Moreover, RT-qPCR found that VhMYB2 was predominantly expressed in the mature leaf and root of the grape. Under salinity and drought stress, overexpressing VhMYB2 showed a higher resistant phenotype and survival rates in A. thaliana while the transgenic lines had a survival advantage by measuring the contents of proline, chlorophyll, and MDA, and activities of POD, SOD, and CAT, and expression levels of related stress response genes. The results reveal that VhMYB2 may be an important transcription factor regulating 'Beta' resistance in response to abiotic stress.


Assuntos
Arabidopsis , Vitis , Arabidopsis/metabolismo , Resistência à Seca , Vitis/genética , Vitis/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Salinidade , Estresse Fisiológico/genética , Secas , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica de Plantas
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