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1.
Immunity ; 54(10): 2231-2244.e6, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34555337

RESUMO

RNA interference (RNAi) is the major antiviral mechanism in plants and invertebrates, but the absence of detectable viral (v)siRNAs in mammalian cells upon viral infection has questioned the functional relevance of this pathway in mammalian immunity. We designed a series of peptides specifically targeting enterovirus A71 (EV-A71)-encoded protein 3A, a viral suppressor of RNAi (VSR). These peptides abrogated the VSR function of EV-A71 in infected cells and resulted in the accumulation of vsiRNAs and reduced viral replication. These vsiRNAs were functional, as evidenced by RISC-loading and silencing of target RNAs. The effects of VSR-targeting peptides (VTPs) on infection with EV-A71 as well as another enterovirus, Coxsackievirus-A16, were ablated upon deletion of Dicer1 or AGO2, core components of the RNAi pathway. In vivo, VTP treatment protected mice against lethal EV-A71 challenge, with detectable vsiRNAs. Our findings provide evidence for the functional relevance of RNAi in mammalian immunity and present a therapeutic strategy for infectious disease.


Assuntos
Antivirais/farmacologia , Infecções por Enterovirus/virologia , RNA Viral/antagonistas & inibidores , Animais , Chlorocebus aethiops , Enterovirus Humano A , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Peptídeos/farmacologia , Interferência de RNA , RNA Interferente Pequeno/antagonistas & inibidores , Células Vero , Replicação Viral/efeitos dos fármacos
2.
PLoS Biol ; 22(3): e3002514, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38483978

RESUMO

The clustered regularly interspaced short palindromic repeat (CRISPR)-Cas12a system is a powerful tool in gene editing; however, crRNA-DNA mismatches might induce unwanted cleavage events, especially at the distal end of the PAM. To minimize this limitation, we engineered a hyper fidelity AsCas12a variant carrying the mutations S186A/R301A/T315A/Q1014A/K414A (termed HyperFi-As) by modifying amino acid residues interacting with the target DNA and crRNA strand. HyperFi-As retains on-target activities comparable to wild-type AsCas12a (AsCas12aWT) in human cells. We demonstrated that HyperFi-As has dramatically reduced off-target effects in human cells, and HyperFi-As possessed notably a lower tolerance to mismatch at the position of the PAM-distal region compared with the wild type. Further, a modified single-molecule DNA unzipping assay at proper constant force was applied to evaluate the stability and transient stages of the CRISPR/Cas ribonucleoprotein (RNP) complex. Multiple states were sensitively detected during the disassembly of the DNA-Cas12a-crRNA complexes. On off-target DNA substrates, the HyperFi-As-crRNA was harder to maintain the R-loop complex state compared to the AsCas12aWT, which could explain exactly why the HyperFi-As has low off-targeting effects in human cells. Our findings provide a novel version of AsCas12a variant with low off-target effects, especially capable of dealing with the high off-targeting in the distal region from the PAM. An insight into how the AsCas12a variant behaves at off-target sites was also revealed at the single-molecule level and the unzipping assay to evaluate multiple states of CRISPR/Cas RNP complexes might be greatly helpful for a deep understanding of how CRISPR/Cas behaves and how to engineer it in future.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Humanos , Sistemas CRISPR-Cas/genética , RNA Guia de Sistemas CRISPR-Cas , Endonucleases/genética , Endonucleases/metabolismo , DNA/genética
3.
PLoS Biol ; 22(5): e3002619, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38814985

RESUMO

The CRISPR-associated endonuclease Cas12a has become a powerful genome-editing tool in biomedical research due to its ease of use and low off-targeting. However, the size of Cas12a severely limits clinical applications such as adeno-associated virus (AAV)-based gene therapy. Here, we characterized a novel compact Cas12a ortholog, termed EbCas12a, from the metagenome-assembled genome of a currently unclassified Erysipelotrichia. It has the PAM sequence of 5'-TTTV-3' (V = A, G, C) and the smallest size of approximately 3.47 kb among the Cas12a orthologs reported so far. In addition, enhanced EbCas12a (enEbCas12a) was also designed to have comparable editing efficiency with higher specificity to AsCas12a and LbCas12a in mammalian cells at multiple target sites. Based on the compact enEbCas12a, an all-in-one AAV delivery system with crRNA for Cas12a was developed for both in vitro and in vivo applications. Overall, the novel smallest high-fidelity enEbCas12a, this first case of the all-in-one AAV delivery for Cas12a could greatly boost future gene therapy and scientific research.


Assuntos
Sistemas CRISPR-Cas , Dependovirus , Edição de Genes , Vetores Genéticos , Dependovirus/genética , Humanos , Edição de Genes/métodos , Vetores Genéticos/genética , Animais , Células HEK293 , Terapia Genética/métodos , Proteínas Associadas a CRISPR/metabolismo , Proteínas Associadas a CRISPR/genética , Camundongos , Endodesoxirribonucleases/metabolismo , Endodesoxirribonucleases/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
4.
Immunity ; 45(3): 555-569, 2016 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-27637147

RESUMO

During viral infection, sensing of cytosolic DNA by the cyclic GMP-AMP synthase (cGAS) activates the adaptor protein STING and triggers an antiviral response. Little is known about the mechanisms that determine the kinetics of activation and deactivation of the cGAS-STING pathway, ensuring effective but controlled innate antiviral responses. Here we found that the ubiquitin ligase Trim38 targets cGas for sumoylation in uninfected cells and during the early phase of viral infection. Sumoylation of cGas prevented its polyubiquitination and degradation. Trim38 also sumoylated Sting during the early phase of viral infection, promoting both Sting activation and protein stability. In the late phase of infection, cGas and Sting were desumoylated by Senp2 and subsequently degraded via proteasomal and chaperone-mediated autophagy pathways, respectively. Our findings reveal an essential role for Trim38 in the innate immune response to DNA virus and provide insight into the mechanisms that ensure optimal activation and deactivation of the cGAS-STING pathway.


Assuntos
Vírus de DNA/imunologia , DNA/metabolismo , Nucleotídeos Cíclicos/metabolismo , Nucleotidiltransferases/metabolismo , Sumoilação/fisiologia , Viroses/metabolismo , Animais , Proteínas de Transporte/metabolismo , Cisteína Endopeptidases/metabolismo , Imunidade Inata/imunologia , Cinética , Proteínas de Membrana/metabolismo , Camundongos , Complexo de Endopeptidases do Proteassoma/metabolismo , Transdução de Sinais/imunologia , Transdução de Sinais/fisiologia , Sumoilação/imunologia , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases , Ubiquitinação/imunologia , Ubiquitinação/fisiologia
5.
Mol Cell ; 66(1): 154-162.e10, 2017 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-28344083

RESUMO

Hedgehog (Hh) has been known as the only cholesterol-modified morphogen playing pivotal roles in development and tumorigenesis. A major unsolved question is how Hh signaling regulates the activity of Smoothened (SMO). Here, we performed an unbiased biochemical screen and identified that SMO was covalently modified by cholesterol on the Asp95 (D95) residue through an ester bond. This modification was inhibited by Patched-1 (Ptch1) but enhanced by Hh. The SMO(D95N) mutation, which could not be cholesterol modified, was refractory to Hh-stimulated ciliary localization and failed to activate downstream signaling. Furthermore, homozygous SmoD99N/D99N (the equivalent residue in mouse) knockin mice were embryonic lethal with severe cardiac defects, phenocopying the Smo-/- mice. Together, the results of our study suggest that Hh signaling transduces to SMO through modulating its cholesterylation and provides a therapeutic opportunity to treat Hh-pathway-related cancers by targeting SMO cholesterylation.


Assuntos
Colesterol/metabolismo , Proteínas Hedgehog/metabolismo , Transdução de Sinais , Receptor Smoothened/metabolismo , Animais , Células CHO , Cílios/metabolismo , Cricetulus , Regulação da Expressão Gênica no Desenvolvimento , Predisposição Genética para Doença , Células HEK293 , Cardiopatias Congênitas/genética , Cardiopatias Congênitas/metabolismo , Proteínas Hedgehog/genética , Humanos , Camundongos , Camundongos Transgênicos , Mutação , Células NIH 3T3 , Receptor Patched-1/genética , Receptor Patched-1/metabolismo , Fenótipo , Processamento de Proteína Pós-Traducional , Interferência de RNA , Receptor Smoothened/genética , Transfecção
6.
Cell Mol Life Sci ; 81(1): 321, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39078462

RESUMO

Allergic asthma is a complex inflammatory disorder predominantly orchestrated by T helper 2 (Th2) lymphocytes. The anti-inflammatory protein Clara Cell 10-kDa (CC10), also known as secretoglobin family 1A member 1 (SCGB1A1), shows promise in modulating respiratory diseases. However, its precise role in asthma remains unclear. This study examines the potential of CC10 to suppress allergic asthma inflammation, specifically assessing its regulatory effects on Th2 cell responses and dendritic cells (DCs). Lower CC10 levels in asthma were observed and correlated with increased IgE and lymphocytes. Cc10-/- mice exhibited exacerbated allergic airway inflammation marked by increased inflammatory cell infiltration, Th2 cytokines, serum antigen-specific IgE levels, and airway hyperresponsiveness (AHR) in house dust mite (HDM)-induced models. Conversely, recombinant CC10 significantly attenuated these inflammatory responses. Intriguingly, CC10 did not directly inhibit Th cell activation but significantly downregulated the population of CD11b+CD103- DCs subsets in lungs of asthmatic mice and modulated the immune activation functions of DCs through NF-κB signaling pathway. The mixed lymphocyte response assay revealed that DCs mediated the suppressive effect of CC10 on Th2 cell responses. Collectively, CC10 profoundly mitigates Th2-type allergic inflammation in asthma by modulating lung DC phenotype and functions, highlighting its therapeutic potential for inflammatory airway conditions and other related immunological disorders.


Assuntos
Asma , Células Dendríticas , Pulmão , Células Th2 , Uteroglobina , Animais , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Asma/imunologia , Asma/patologia , Células Th2/imunologia , Células Th2/metabolismo , Uteroglobina/genética , Uteroglobina/metabolismo , Camundongos , Pulmão/patologia , Pulmão/imunologia , Pulmão/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Inflamação/patologia , Inflamação/imunologia , Inflamação/metabolismo , Imunoglobulina E/imunologia , Imunoglobulina E/sangue , Pyroglyphidae/imunologia , NF-kappa B/metabolismo , Citocinas/metabolismo , Feminino , Camundongos Endogâmicos BALB C
7.
Genomics ; 116(5): 110916, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39147332

RESUMO

Bile cell-free DNA (cfDNA) has been reported as a promising liquid biopsy tool for cholangiocarcinoma (CCA), however, the whole-genome mutation landscape and structural variants (SVs) of bile cfDNA remains unknown. Here we performed whole-genome sequencing on bile cfDNA and analyzed the correlation between mutation characteristics of bile cfDNA and clinical prognosis. TP53 and KRAS were the most frequently mutated genes, and the RTK/RAS, homologous recombination (HR), and HIPPO were top three pathways containing most gene mutations. Ten overlapping putative driver genes were found in bile cfDNA and tumor tissue. SVs such as chromothripsis and kataegis were identified. Moreover, the hazard ratio of HR pathway mutations were 15.77 (95% CI: 1.571-158.4), patients with HR pathway mutations in bile cfDNA exhibited poorer overall survival (P = 0.0049). Our study suggests that bile cfDNA contains genome mutations and SVs, and HR pathway mutations in bile cfDNA can predict poor outcomes of CCA patients.


Assuntos
Neoplasias dos Ductos Biliares , Ácidos Nucleicos Livres , Colangiocarcinoma , Mutação , Humanos , Colangiocarcinoma/genética , Neoplasias dos Ductos Biliares/genética , Masculino , Feminino , Pessoa de Meia-Idade , Ácidos Nucleicos Livres/genética , Idoso , Sequenciamento Completo do Genoma , Genoma Humano , Bile/química , Bile/metabolismo , Prognóstico , Adulto
8.
Nano Lett ; 24(26): 7843-7851, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38912682

RESUMO

Two-dimensional-material-based memristors are emerging as promising enablers of new computing systems beyond von Neumann computers. However, the most studied anion-vacancy-enabled transition metal dichalcogenide memristors show many undesirable performances, e.g., high leakage currents, limited memory windows, high programming currents, and limited endurance. Here, we demonstrate that the emergent van der Waals metal phosphorus trisulfides with unconventional nondefective vacancy provide a promising paradigm for high-performance memristors. The different vacancy types (i.e., defective and nondefective vacancies) induced memristive discrepancies are uncovered. The nondefective vacancies can provide an ultralow diffusion barrier and good memristive structure stability giving rise to many desirable memristive performances, including high off-state resistance of 1012 Ω, pA-level programming currents, large memory window up to 109, more than 7-bit conductance states, and good endurance. Furthermore, a high-yield (94%) memristor crossbar array is fabricated and implements multiple image processing successfully, manifesting the potential for in-memory computing hardware.

9.
Nano Lett ; 24(6): 2118-2124, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38305203

RESUMO

Ferroelectric two-dimensional (2D) materials with a high transition temperature are highly desirable for new physics and next-generation memory electronics. However, the long-range polar order of ferroelectrics will barely persist when the thickness reaches the nanoscale. In this work, we synthesized 2D CuCrS2 nanosheets with thicknesses down to one unit cell via van der Waals epitaxy in a chemical vapor deposition system. A combination of transmission electron microscopy, second-harmonic generation, and Raman spectroscopy measurements confirms the R3m space group and noncentrosymmetric structure. Switchable ferroelectric domains and obvious ferroelectric hysteresis loops were created and visualized by piezoresponse force microscopy. Theoretical calculation helps us understand the mechanism of ferroelectric switching in CuCrS2 nanosheets. Finally, we fabricated a ferroelectric memory device that achieves an on/off ratio of ∼102 and remains stable after 2000 s, indicating its applicability in novel nanoelectronics. Overall, 2D CuCrS2 nanosheets exhibit excellent ferroelectric properties at the nanoscale, showing great promise for next-generation devices.

10.
Cancer Immunol Immunother ; 73(7): 116, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713408

RESUMO

OBJECTIVES: Nivolumab is approved as adjuvant therapy for resected stage III/IV melanoma based on the phase 3 CheckMate 238 trial. This analysis compared outcomes from CheckMate 238 with those from the real-world Flatiron Health electronic health record-derived de-identified database in patients with resected stage III melanoma (per AJCC-8) treated with adjuvant nivolumab. MATERIALS: Outcomes included baseline characteristics, overall survival (OS) in the CheckMate 238 cohort (randomization until death or last known alive), and real-world overall survival (rwOS) in the Flatiron Health cohort (nivolumab initiation until death or data cutoff). rwOS was compared with OS using unadjusted and adjusted Cox proportional hazards models. Inverse probability of treatment weighting (IPTW) was combined with the adjusted model to reduce baseline discrepancies. RESULTS: The CheckMate 238 and real-world cohorts included 369 and 452 patients, respectively (median age, 56.0 and 63.0 years; median follow-up, 61.4 vs. 25.5 months). rwOS was not different from OS in the unadjusted (hazard ratio [HR] 1.27; 95% CI 0.92-1.74), adjusted (HR 1.01; 95% CI 0.67-1.54), and adjusted IPTW (HR 1.07; 95% CI 0.70-1.63) analyses. In the adjusted analysis, 2-year OS and rwOS rates were 84%. Median OS and rwOS were not reached. After IPTW, OS and rwOS were not different (HR 1.07; 95% CI 0.70-1.64). CONCLUSIONS: In this comparative analysis, OS in the CheckMate 238 trial was similar to rwOS in the Flatiron Health database after adjustments in patients with resected stage III melanoma (per AJCC-8) treated with adjuvant nivolumab, validating the trial results.


Assuntos
Melanoma , Estadiamento de Neoplasias , Nivolumabe , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Antineoplásicos Imunológicos/uso terapêutico , Quimioterapia Adjuvante/métodos , Melanoma/tratamento farmacológico , Melanoma/mortalidade , Melanoma/patologia , Melanoma/cirurgia , Nivolumabe/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia , Resultado do Tratamento
11.
Small ; 20(11): e2304308, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37936314

RESUMO

Thermal energy harvesting provides an opportunity for multi-node systems to achieve self-power autonomy. Thermoelectric generators (TEGs), either by thermocouple arrangement with higher-aspect-ratios or thermoelectric films overlay, are limited by the small temperature difference and its short-duration (less than dozens of minutes), hindering the harvesting efficiency. Here, by introducing thermal diodes with dual-direction thermal regulation ability to optimize the heat flux path, the proposed TEGs exhibit enhanced power-supply capability with unprecedented long-duration (more than hours). In contrast with conventional TEGs with fixed-leg dimensions enabled single output, these compact-TEGs can supply up to fourteen output-channels for selection, the produced power ranges from 1.11 to 921.99 µW, open circuit voltage ranges from 8.07 to 51.32 mV, when the natural temperature difference is 53.84 °C. Compared to the most recent TEGs, the proposed TEGs in this study indicate higher power (more than hundreds times) and much longer output duration (2.4-120 times) in a compact manner.

12.
J Transl Med ; 22(1): 203, 2024 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-38403590

RESUMO

Resident memory T (Trm) cells which are specifically located in non-lymphoid tissues showed distinct phenotypes and functions compared to circulating memory T cells and were vital for the initiation of robust immune response within tissues. However, the heterogeneity in the transcriptional features, development pathways, and cancer response of Trm cells in the small intestine was not demonstrated. Here, we integrated scRNA-seq and scTCR-seq data pan-tissue T cells to explore the heterogeneity of Trm cells and their development pathways. Trm were enriched in tissue-specific immune response and those in the DUO specially interacted with B cells via TNF and MHC-I signatures. T cell lineage analyses demonstrated that Trm might be derived from the T_CD4/CD8 subset within the same organ or migrated from spleen and mesenteric lymph nodes. We compared the immune repertoire of Trm among organs and implied that clonotypes in both DUO and ILE were less expanded and hydrophilic TRB CDR3s were enriched in the DUO. We further demonstrated that Trm in the intestine infiltrated the colorectal cancer and several effector molecules were highly expressed. Finally, the TCGA dataset of colorectal cancer implied that the infiltration of Trm from the DUO and the ILE was beneficial for overall survival and the response to immune checkpoint blockade.


Assuntos
Neoplasias Colorretais , Memória Imunológica , Humanos , Células T de Memória , Relevância Clínica , Linfócitos T CD8-Positivos , Intestino Delgado , Análise de Célula Única , Neoplasias Colorretais/metabolismo
13.
PLoS Pathog ; 18(11): e1010989, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36449507

RESUMO

The mediator of IRF3 activation (MITA, also named STING) is critical for immune responses to abnormal cytosolic DNA and has been considered an important drug target in the clinical therapy of tumors and autoimmune diseases. In the present study, we report that MITA undergoes DDOST-mediated N-glycosylation in the endoplasmic reticulum (ER) upon DNA viral infection. Selective mutation of DDOST-dependent N-glycosylated residues abolished MITA oligomerization and thereby its immune functions. Moreover, increasing the expression of Ddost in the mouse brain effectively strengthens the local immune response to herpes simplex virus-1 (HSV-1) and prolongs the survival time of mice with HSV encephalitis (HSE). Our findings reveal the dependence of N-glycosylation on MITA activation and provide a new perspective on the pathogenesis of HSE.


Assuntos
Doenças Autoimunes , Encefalite por Herpes Simples , Herpesvirus Humano 1 , Viroses , Animais , Camundongos , Glicosilação
14.
Anal Biochem ; 688: 115476, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38286351

RESUMO

The aim of this work was to develop a fast, simple, and reliable UPLC-MS3 method for the sensitive detection of acetochlor in biological samples. In MS3 mode, the ion transition m/z 270.1 â†’ 224.1→148.1 was chosen for quantification with butachlor as the internal standard. In the UPLC system, separation was performed on a UPLC column (2.1 × 50 mm ID, 1.7 µm) with 0.1 % FA in water and acetonitrile as mobile phases. After simple protein precipitation via acetonitrile, the method was well validated with good linearity (0.5-20 ng/mL, r > 0.995), accuracy (-3.70 %-2.98 %), and precision (<15 %). The selectivity and sensitivity were improved obviously in MS3 mode than that in MRM mode. The developed UPLC-MS3 method was successfully applied to the cellular pharmacokinetics study of acetochlor in MCF-7 cells.


Assuntos
Espectrometria de Massa com Cromatografia Líquida , Espectrometria de Massas em Tandem , Toluidinas , Cromatografia Líquida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Reprodutibilidade dos Testes , Acetonitrilas
15.
BMC Vet Res ; 20(1): 288, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961481

RESUMO

BACKGROUND: Porcine epidemic diarrhea virus (PEDV) mainly causes acute and severe porcine epidemic diarrhea (PED), and is highly fatal in neonatal piglets. No reliable therapeutics against the infection exist, which poses a major global health issue for piglets. Luteolin is a flavonoid with anti-viral activity toward several viruses. RESULTS: We evaluated anti-viral effects of luteolin in PEDV-infected Vero and IPEC-J2 cells, and identified IC50 values of 23.87 µM and 68.5 µM, respectively. And found PEDV internalization, replication and release were significantly reduced upon luteolin treatment. As luteolin could bind to human ACE2 and SARS-CoV-2 main protease (Mpro) to contribute viral entry, we first identified that luteolin shares the same core binding site on pACE2 with PEDV-S by molecular docking and exhibited positive pACE2 binding with an affinity constant of 71.6 µM at dose-dependent increases by surface plasmon resonance (SPR) assay. However, pACE2 was incapable of binding to PEDV-S1. Therefore, luteolin inhibited PEDV internalization independent of PEDV-S binding to pACE2. Moreover, luteolin was firmly embedded in the groove of active pocket of Mpro in a three-dimensional docking model, and fluorescence resonance energy transfer (FRET) assays confirmed that luteolin inhibited PEDV Mpro activity. In addition, we also observed PEDV-induced pro-inflammatory cytokine inhibition and Nrf2-induced HO-1 expression. Finally, a drug resistant mutant was isolated after 10 cell culture passages concomitant with increasing luteolin concentrations, with reduced PEDV susceptibility to luteolin identified at passage 10. CONCLUSIONS: Our results push forward that anti-PEDV mechanisms and resistant-PEDV properties for luteolin, which may be used to combat PED.


Assuntos
Antivirais , Luteolina , Vírus da Diarreia Epidêmica Suína , Luteolina/farmacologia , Vírus da Diarreia Epidêmica Suína/efeitos dos fármacos , Animais , Antivirais/farmacologia , Chlorocebus aethiops , Células Vero , Suínos , Simulação de Acoplamento Molecular , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Linhagem Celular , Simulação por Computador , Doenças dos Suínos/virologia , Doenças dos Suínos/tratamento farmacológico
16.
Neurol Sci ; 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39212793

RESUMO

BACKGROUND: Cognitive impairment is one of the most common symptoms of Parkinson's disease (PD), and may be detectable through changes in neural features visualized by magnetic resonance imaging (MRI). Mild cognitive impairment is a transitional state between normal aging and dementia, and early recognition of Parkinson's disease with mild cognitive impairment (PD-MCI) can help improve the quality of life and treatment for patients. This study investigated the association of enlarged perivascular space (EPVS) and white matter hyperintensity (WMH) with PD-MCI. AIMS: This study aimed to evaluate whether EPVS and WMH can be used as potential MRI markers for PD-MCI. METHODS: This retrospective study involved 200 patients with PD who underwent cranial MRI in our hospital from April 2021 to April 2022. Patients were divided into those with no cognitive impairment (PD-NCI) or mild cognitive impairment. Uni- and multivariate logistic regression analyzed associations of EPVS, WMH, and clinicodemographic characteristics with cognitive decline. RESULTS: Univariate regression identified severe EPVS in basal ganglia, severe WMH, older age, late-onset, male sex, low educational level, longer duration of disease, low triglycerides, low uric acid, and low scores on the Mini-mental State Exam as risk factors for PD-MCI. After adjusting for clinicodemographic risk factors in multivariate regression, low education level and EPVS in basal ganglia remained risk factors for cognitive impairment. CONCLUSIONS: Severe EPVS in basal ganglia and poor education, but not WMH, are independent risk factors of PD-MCI. Our findings suggest that non-invasive detection of EPVS in basal ganglia by MRI may be a valuable early indicator of cognitive decline in PD patients.

17.
J Sep Sci ; 47(2): e2300802, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38286730

RESUMO

Polyethylene glycol (PEG) is one of the most commonly used polymers in drug delivery systems. The investigation of the pharmacokinetic behavior of PEG is important for revealing the toxicity and efficiency of PEG-related Nano-drug delivery systems. A high through-put and selective ultra-high-performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) method coupled with collision-induced dissociation (CID) in source technique was developed and validated to determine PEG1K polymers in cellular samples in this study. The countless precursor ions of PEG1K are dissociated in the source to generate numerous product ions which have different numbers of subunits. The transition of [M+H]+ precursor ions → product ions at m/z 177.1 (four subunits)→89.1 (two subunits) was selected to determine PEG1K due to its high sensitivity. The UHPLC-MS/MS method coupled with CID in the source showed good linearity over the range of 0.1-10 µg/mL. Intra-day and inter-day accuracies and precisions of the assay were all within ± 12.39%. The assay was successfully applied to a cellular pharmacokinetic study of PEG1K in human breast cancer cells. The cytotoxicity of PEG1K polymers was also studied and the results indicated that the cytotoxicity of PEG1K was not significant in the range of 5-1200 µg/mL.


Assuntos
Polímeros , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Polímeros/toxicidade , Polímeros/análise , Polietilenoglicóis/química , Íons
18.
BMC Public Health ; 24(1): 1850, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992612

RESUMO

BACKGROUND: Myopia is a major health issue around the world. Myopia in children has increased significantly during the COVID-19 pandemic in China, but reports are scarce on the prevalence of myopia following the pandemic. This study collected vision screening data of school children in China for five consecutive years to observe the changes in myopia after the pandemic and compare the observed prevalence of myopia before and after the pandemic. METHODS: A school-based vision screening study used stratified samplings to collect the vision screening data in school children aged 6-13 from 45 primary schools in Hangzhou. Vision screening data including uncorrected visual acuity(UCVA) and spherical equivalent refraction(SER). Calculating the mean of SER and the prevalence of myopia and hyperopia from 2019 to 2023. RESULTS: A total of 79,068 screening results (158,136 eyes) were included in the analysis. A substantial myopic shift (approximately -0.30 diopters [D] on average) was found in 2020 and 2021 compared with 2019 in all age groups and a substantial myopic shift (approximately 0.4 D on average) was found in 2022 compared with 2021. A slight myopic shift (approximately -0.14 D on average) was found in 2023 compared with 2022. The prevalence of myopia in all age groups was the highest for five years in 2020 or 2021, which was 31.3% for 6-year-olds, 43.0% for 7-year-olds, and 53.7% for 8-year-olds. A positive change in the prevalence rate of myopia was found at 6 years old (0.59%, 0.12%, 0.36%, 0.25%, p < 0.001). The change in prevalence rate in myopia was shifted slightly in children aged 10-13 years. Children aged 8 to 13 years had a slight increase in myopia prevalence from 2022 to 2023. The prevalence of hyperopia was low and stable in all grade groups, ranging from 0.7% to 2.2% over five years. CONCLUSION: Myopia in children has increased rapidly during the COVID-19 pandemic. After the pandemic, the prevalence of myopia in children gradually decreased temporarily and then rebounded. Myopic shift was more apparent in younger children. Myopic shift in children may be related to the reduction of outdoor time, less light, and near work habits, and further research is needed.


Assuntos
COVID-19 , Miopia , Seleção Visual , Humanos , COVID-19/epidemiologia , Criança , Miopia/epidemiologia , China/epidemiologia , Masculino , Adolescente , Feminino , Prevalência , Instituições Acadêmicas , Pandemias
19.
Proc Natl Acad Sci U S A ; 118(23)2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34074778

RESUMO

Tumors frequently express unmutated self-tumor-associated antigens (self-TAAs). However, trial results using self-TAAs as vaccine targets against cancer are mixed, often attributed to deletion of T cells with high-affinity receptors (TCRs) for self-TAAs during T cell development. Mutating these weak self-TAAs to produce higher affinity, effective vaccines is challenging, since the mutations may not benefit all members of the broad self-TAA-specific T cell repertoire. We previously identified a common weak murine self-TAA that we converted to a highly effective antitumor vaccine by a single amino acid substitution. In this case the modified and natural self-TAAs still raised very similar sets of CD8 T cells. Our structural studies herein show that the modification of the self-TAA resulted in a subtle change in the major histocompatibility complex I-TAA structure. This amino acid substitution allowed a dramatic conformational change in the peptide during subsequent TCR engagement, creating a large increase in TCR affinity and accounting for the efficacy of the modified self-TAA as a vaccine. These results show that carefully selected, well-characterized modifications to a poorly immunogenic self-TAA can rescue the immune response of the large repertoire of weakly responding natural self-TAA-specific CD8 T cells, driving them to proliferate and differentiate into functional effectors. Subsequently, the unmodified self-TAA on the tumor cells, while unable to drive this response, is nevertheless a sufficient target for the CD8 cytotoxic effectors. Our results suggest a pathway for more efficiently identifying variants of common self-TAAs, which could be useful in vaccine development, complementing other current nonantigen-specific immunotherapies.


Assuntos
Antígenos de Neoplasias/imunologia , Autoantígenos/imunologia , Linfócitos T CD8-Positivos/imunologia , Neoplasias Experimentais/imunologia , Peptídeos/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Animais , Vacinas Anticâncer/imunologia , Linhagem Celular Tumoral , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Experimentais/prevenção & controle , Células Sf9 , Spodoptera
20.
Nano Lett ; 23(18): 8460-8467, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37721358

RESUMO

Neuromorphic vision has been attracting much attention due to its advantages over conventional machine vision (e.g., lower data redundancy and lower power consumption). Here we develop synaptic phototransistors based on the silicon nanomembrane (Si NM), which are coupled with lead sulfide quantum dots (PbS QDs) and poly(3-hexylthiophene) (P3HT) to form a heterostructure with distinct photogating. Synaptic phototransistors with optical stimulation have outstanding synaptic functionalities ranging from ultraviolet (UV) to near-infrared (NIR). The broadband synaptic functionalities enable an array of synaptic phototransistors to achieve the perception of brightness and color. In addition, an array of synaptic phototransistors is capable of simultaneous sensing, processing, and memory, which well mimics human vision.

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