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1.
Nano Lett ; 24(23): 6889-6896, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38739156

RESUMO

Thermal conductivity is a critical material property in numerous applications, such as those related to thermoelectric devices and heat dissipation. Effectively modulating thermal conductivity has become a great concern in the field of heat conduction. Here, a quantum modulation strategy is proposed to modulate the thermal conductivity/heat flux by exciting targeted phonons. It shows that the thermal conductivity of graphene can be tailored in the range of 1559 W m-1 K-1 (decreased to 49%) to 4093 W m-1 K-1 (increased to 128%), compared with the intrinsic value of 3189 W m-1 K-1. The effects are also observed for graphene nanoribbons and bulk silicon. The results are obtained through both density functional theory calculations and molecular dynamics simulations. This novel modulation strategy may pave the way for quantum heat conduction.

2.
BMC Cancer ; 24(1): 755, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38907210

RESUMO

BACKGROUND: The role of hemoglobin (HGB) in common malignant tumors remains unclear. METHODS: A retrospective analysis was conducted to identify the correlation between HGB levels and risk of 15 malignant tumors using 50,085 samples from the National Health and Nutrition Examination Survey. Mendelian Randomization analyses (MRAs) were performed based on genome-wide association study data to assess the causal relationship between HGB levels and these malignant tumors using more than 700,000 samples. The robustness of the MRA results was confirmed through various analytical methods. Fifty-six in-house samples were used to investigate the correlation between HGB levels and the prognosis in prostate cancer (PRCA) using the Kaplan-Meier curve. RESULTS: High HGB levels were associated with a higher risk for patients with cervix cancer, melanoma, and non-melanoma skin cancer (OR > 1.000, p < 0.05). It served as a protective factor for colon cancer, esophagus cancer, stomach cancer, bone cancer, lung cancer, renal cancer, and PRCA (OR < 1.000, p < 0.05). Furthermore, MRAs suggested that elevated HGB levels were correlated with a reduced risk of PRCA (OR = 0.869, p < 0.05), with no significant association observed between this marker and the remaining 14 malignant tumors. No pleiotropy or heterogeneity was found in the ultimate results for MRAs (p-values > 0.05), suggesting the robustness of the results. The results derived from the in-house data revealed a relationship between higher HGB values and a more favorable prognosis in PRCA (p < 0.05). CONCLUSION: High circulating HGB levels may play a protective prognostic role for PRCA and serve as a protective factor against the occurrence of PRCA.


Assuntos
Hemoglobinas , Neoplasias , Humanos , Estudos Retrospectivos , Masculino , Feminino , Hemoglobinas/análise , Neoplasias/epidemiologia , Neoplasias/sangue , Neoplasias/genética , Estudo de Associação Genômica Ampla , Prognóstico , Pessoa de Meia-Idade , Análise da Randomização Mendeliana , Fatores de Risco , Inquéritos Nutricionais , Adulto , Idoso , Biomarcadores Tumorais/sangue
3.
BMC Pediatr ; 24(1): 96, 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310242

RESUMO

BACKGROUND: NARS2 as a member of aminoacyl-tRNA synthetases was necessary to covalently join a specific tRNA to its cognate amino acid. Biallelic variants in NARS2 were reported with disorders such as Leigh syndrome, deafness, epilepsy, and severe myopathy. CASE PRESENTATION: Detailed clinical phenotypes were collected and the NARS2 variants were discovered by whole exome sequencing and verified by Sanger sequencing. Additionally, 3D protein structure visualization was performed by UCSF Chimera. The proband in our study had early-onset status epilepticus with abnormal EEG and MRI results. She also performed global developmental delay (GDD) and myocardial dysfunction. Next-generation sequencing (NGS) and Sanger sequencing revealed compound heterozygous missense variants [NM_024678.6:exon14: c.1352G > A(p.Arg451His); c.707T > C(p.Phe236Ser)] of the NARS2 gene. The proband develops refractory epilepsy with GDD and hyperlactatemia. Unfortunately, she finally died for status seizures two months later. CONCLUSION: We discovered two novel missense variants of NARS2 in a patient with early-onset status epilepticus and myocardial dysfunction. The NGS enables the patient to be clearly diagnosed as combined oxidative phosphorylation deficiency 24 (COXPD24, OMIM:616,239), and our findings expands the spectrum of gene variants in COXPD24.


Assuntos
Aspartato-tRNA Ligase , Epilepsia Resistente a Medicamentos , Epilepsia , Estado Epiléptico , Feminino , Humanos , Estado Epiléptico/diagnóstico , Estado Epiléptico/genética , Epilepsia Resistente a Medicamentos/genética , Mutação de Sentido Incorreto , RNA de Transferência , Mutação , Aspartato-tRNA Ligase/genética
4.
Int J Mol Sci ; 25(17)2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39273091

RESUMO

Rabies is a fatal neurological infectious disease caused by rabies virus (RABV), which invades the central nervous system (CNS). RABV with varying virulence regulates chemokine expression, and the mechanisms of signaling pathway activation remains to be elucidated. The relationship between Toll-like receptors (TLRs) and immune response induced by RABV has not been fully clarified. Here, we investigated the role of TLR7 in the immune response induced by RABV, and one-way analysis of variance (ANOVA) was employed to evaluate the data. We found that different RABV strains (SC16, HN10, CVS-11) significantly increased CCL2, CXCL10 and IL-6 production. Blocking assays indicated that the TLR7 inhibitor reduced the expression of CCL2, CXCL10 and IL-6 (p < 0.01). The activation of the Myd88 pathway in BV-2 cells stimulated by RABV was TLR7-dependent, whereas the inhibition of Myd88 activity reduced the expression of CCL2, CXCL10 and IL-6 (p < 0.01). Meanwhile, the RABV stimulation of BV-2 cells resulted in TRL7-mediated activation of NF-κB and induced the nuclear translocation of NF-κB p65. CCL2, CXCL10 and IL-6 release was attenuated by the specific NF-κB inhibitor used (p < 0.01). The findings above demonstrate that RABV-induced expression of CCL2, CXCL10 and IL-6 involves Myd88 and NF-κB pathways via the TLR7 signal.


Assuntos
Fator 88 de Diferenciação Mieloide , NF-kappa B , Vírus da Raiva , Transdução de Sinais , Receptor 7 Toll-Like , Receptor 7 Toll-Like/metabolismo , Animais , Fator 88 de Diferenciação Mieloide/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Vírus da Raiva/patogenicidade , Vírus da Raiva/imunologia , Camundongos , NF-kappa B/metabolismo , Linhagem Celular , Interleucina-6/metabolismo , Quimiocina CCL2/metabolismo , Quimiocina CCL2/genética , Quimiocina CXCL10/metabolismo , Quimiocina CXCL10/genética , Raiva/virologia , Raiva/metabolismo , Raiva/imunologia , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/genética , Inflamação/metabolismo
5.
Lancet Oncol ; 24(8): 855-867, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37541271

RESUMO

BACKGROUND: The emergence of COVID-19 disrupted health care, with consequences for cancer diagnoses and outcomes, especially for early stage diagnoses, which generally have favourable prognoses. We aimed to examine nationwide changes in adult cancer diagnoses and stage distribution during the first year of the COVID-19 pandemic by cancer type and key sociodemographic factors in the USA. METHODS: In this cross-sectional study, adults (aged ≥18 years) newly diagnosed with a first primary malignant cancer between Jan 1, 2018, and Dec 31, 2020, were identified from the US National Cancer Database. We included individuals across 50 US states and the District of Columbia who were treated in hospitals that were Commission on Cancer-accredited during the study period. Individuals whose cancer stage was 0 (except for bladder cancer), occult, or without an applicable American Joint Committee on Cancer staging scheme were excluded. Our primary outcomes were the change in the number and the change in the stage distribution of new cancer diagnoses between 2019 (Jan 1 to Dec 31) and 2020 (Jan 1 to Dec 31). Monthly counts and stage distributions were calculated for all cancers combined and for major cancer types. We also calculated annual change in stage distribution from 2019 to 2020 and adjusted odds ratios (aORs) using multivariable logistic regression, adjusted for age group, sex, race and ethnicity, health insurance status, comorbidity score, US state, zip code-level social deprivation index, and county-level age-adjusted COVID-19 mortality in 2020. Separate models were stratified by sociodemographic and clinical factors. FINDINGS: We identified 2 404 050 adults who were newly diagnosed with cancer during the study period (830 528 in 2018, 849 290 in 2019, and 724 232 in 2020). Mean age was 63·5 years (SD 13·5) and 1 287 049 (53·5%) individuals were women, 1 117 001 (46·5%) were men, and 1 814 082 (75·5%) were non-Hispanic White. The monthly number of new cancer diagnoses (all stages) decreased substantially after the start of the COVID-19 pandemic in March, 2020, although monthly counts returned to near pre-pandemic levels by the end of 2020. The decrease in diagnoses was largest for stage I disease, leading to lower odds of being diagnosed with stage I disease in 2020 than in 2019 (aOR 0·946 [95% CI 0·939-0·952] for stage I vs stage II-IV); whereas, the odds of being diagnosed with stage IV disease were higher in 2020 than in 2019 (1·074 [1·066-1·083] for stage IV vs stage I-III). This pattern was observed in most cancer types and sociodemographic groups, although was most prominent among Hispanic individuals (0·922 [0·899-0·946] for stage I; 1·110 [1·077-1·144] for stage IV), Asian American and Pacific Islander individuals (0·924 [0·892-0·956] for stage I; 1·096 [1·052-1·142] for stage IV), uninsured individuals (0·917 [0·875-0·961] for stage I; 1·102 [1·055-1·152] for stage IV), Medicare-insured adults younger than 65 years (0·909 [0·882-0·937] for stage I; 1·105 [1·068-1·144] for stage IV), and individuals living in the most socioeconomically deprived areas (0·931 [0·917-0·946] for stage I; 1·106 [1·087-1·125] for stage IV). INTERPRETATION: Substantial cancer underdiagnosis and decreases in the proportion of early stage diagnoses occurred during 2020 in the USA, particularly among medically underserved individuals. Monitoring the long-term effects of the pandemic on morbidity, survival, and mortality is warranted. FUNDING: None.


Assuntos
COVID-19 , Neoplasias , Adulto , Masculino , Humanos , Idoso , Feminino , Estados Unidos/epidemiologia , Adolescente , Pessoa de Meia-Idade , COVID-19/epidemiologia , Estudos Transversais , Pandemias , Medicare , Neoplasias/diagnóstico , Neoplasias/epidemiologia , Neoplasias/patologia
6.
Epilepsy Behav ; 135: 108876, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36088785

RESUMO

OBJECTIVE: Although clinical trials have demonstrated that cathodal transcranial direct current stimulation (tDCS) is effective for seizure reduction, its long-term efficacy is unknown. This study aimed to determine the long-term effects of repeated cathodal long tDCS sessions on seizure suppression in patients with refractory epilepsy. METHODS: Patients were recruited to participate in an extended phase of a previous randomized, double-blind, sham-controlled, three-arm, parallel, multicenter study on tDCS. The patients were divided into an active tDCS group (20 min of tDCS per day) and an intensified tDCS group (2 × 20 min of tDCS per day). Each tDCS session lasted 2 weeks and the patients underwent repeated sessions at intervals of 2 to 6 months. The cathode was placed over the epileptogenic focus with the current intensity set as 2 mA. Seizure frequency reduction from baseline was analyzed using the Wilcoxon signed-rank test for two related samples. A generalized estimating equation model was used to estimate group, time, and interaction effects. RESULTS: Among the 19 patients who participated in the extended phase, 11 were in the active tDCS group and underwent 2-16 active tDCS sessions, and eight were in the intensified tDCS group and underwent 3-11 intensified tDCS sessions. Seizure reduction was significant from the first to the seventh follow-up, with a median seizure frequency reduction of 41.7%-83.3% (p < 0.05). Compared to the regular tDCS protocol, each intensified tDCS session substantially decreased seizure frequency by 0.3680 (p < 0.05). One patient experienced an increase of 8.5%-232.8% in the total number of seizures during three treatment sessions and follow-ups. CONCLUSION: Repeated long cathodal tDCS sessions yielded significant and progressive long-term seizure reductions in patients with refractory focal epilepsy.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsias Parciais , Estimulação Transcraniana por Corrente Contínua , Método Duplo-Cego , Epilepsia Resistente a Medicamentos/etiologia , Epilepsia Resistente a Medicamentos/terapia , Epilepsias Parciais/etiologia , Epilepsias Parciais/terapia , Humanos , Convulsões/etiologia , Convulsões/terapia , Estimulação Transcraniana por Corrente Contínua/métodos
7.
J Appl Microbiol ; 132(3): 1666-1674, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34309977

RESUMO

AIM: To determine the molecular epidemiology, genotypes and phenotypes of the major species of Streptococcus associated with bovine subclinical mastitis in Hainan, China. METHODS AND RESULTS: In total, 150 subclinical mastitis milk samples were collected from two large dairy farms in Hainan. On the basis of biochemical tests and 16S rDNA sequencing, 39 samples were Streptococcus positive and the most frequently isolated species was Streptococcus uberis (n = 29, 74.4%). According to multilocus sequence typing (MLST), and assays of biofilm formation, antimicrobial susceptibility, resistance and virulence genes, the S. uberis isolates were clustered into nine new sequence types (STs; ST986-ST994) but were not merged into a clonal group (except for ST991 [CC143]). All isolates produced biofilm, but most weakly. The dominant virulence pattern was hasABC + sua + gapC + oppF + pauA + mtuA + cfu (27/29, 91.1%), based on the 11 virulence genes tested. The majority of isolates (88.46%) carried at least one resistance gene, and more than half (58.62%) were multidrug-resistant. The main resistance genes were linB (65.5%), ermB (37.9%) and tetS (34.5%), among the six antibiotic resistance genes and 11 antimicrobials tested. CONCLUSION: Environmental S. uberis is important in bovine subclinical mastitis in Hainan. SIGNIFICANCE AND IMPACT OF THE STUDY: Streptococcus uberis isolates in Hainan, China, show distinct MLST, virulence and antibiotic resistance characteristics.


Assuntos
Mastite Bovina , Infecções Estreptocócicas , Animais , Bovinos , China/epidemiologia , Feminino , Humanos , Mastite Bovina/epidemiologia , Tipagem de Sequências Multilocus , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/veterinária , Streptococcus
8.
J Chem Phys ; 157(17): 174303, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36347693

RESUMO

Maintaining stability of single-molecular junctions (SMJs) in the presence of current flow is a prerequisite for their potential device applications. However, theoretical understanding of nonequilibrium heat transport in current-carrying SMJs is a challenging problem due to the different kinds of nonlinear interactions involved, including electron-vibration and anharmonic vibrational coupling. Here, we overcome this challenge by accelerating Langevin-type current-induced molecular dynamics using machine-learning potential derived from density functional theory. We show that SMJs with graphene electrodes generate an order of magnitude less heating than those with gold electrodes. This is rooted in the better phonon spectral overlap of graphene with molecular vibrations, rendering harmonic phonon heat transport being dominant. In contrast, in a spectrally mismatched junction with gold electrodes, anharmonic coupling becomes important to transport heat away from the molecule to surrounding electrodes. Our work paves the way for studying current-induced heat transport and energy redistribution in realistic SMJs.

9.
Microb Pathog ; 149: 104577, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33122048

RESUMO

Aeromous veronii is a severe pathogen that can infect aquatic organisms and mammals also causes irreparable damage to fish aquaculture. Analysis of the results of epidemiological investigations have revealed that its tolerance to drugs and the virulence of A. veronii have increased in recent years. Most of the researches on A. veronii focuse on the strain isolation, identification, and drug susceptibility. However, we do not know so much about the molecular mechanism of the pathogenesis on A. veronii. Here we identified and obtained the highly expressed TH0426 Nucleoside Diphosphate Kinases (NDK) of A. veronii. We first constructed a mutant strain (△-ndk) by generating an in-frame deletion of the ndk gene, to investigate the functional role in A. veronii TH0426. The ability in the adhesion and invasion of EPC cells and biofilm formation significantly reduced of the △-ndk strain. The motility test showed that the ndk gene affected on the swimming ability, while did not affect the swarming motility. Compared with the wild-type strain TH0426, the pathogenicity of △-ndk strain to zebrafish reduced severely. Besides, the ndk gene has affected the apoptosis rate of A. veronii TH0426. These results would help to demonstrate the function of ndk further and realize the pathogenesis on A. veronii.


Assuntos
Aeromonas veronii , Núcleosídeo-Difosfato Quinase , Animais , Aquicultura , Núcleosídeo-Difosfato Quinase/genética , Virulência , Peixe-Zebra
10.
Int J Med Sci ; 17(12): 1683-1691, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32714071

RESUMO

The filamentous actin (F-actin) cytoskeleton is progressively damaged after status epilepticus (SE), which is related to delayed neuronal death, aberrant recurrent circuits and epileptogenesis. Glucocorticoids regulate dendritic spine remodeling by acting on glucocorticoid receptors and the dynamics of the F-actin cytoskeleton. Our previous study showed that administration of dexamethasone (DEX) in the latent period of the pilocarpine epileptic model reduces damage to the hippocampal filamentous actin cytoskeleton and the loss of hippocampal neurons and aids in maintaining the synaptic structures, but it is not sufficient to stop epileptogenesis. In this work, we focused on the role of glucocorticoids in regulating the hippocampal F-actin cytoskeleton during SE. We examined the abundance of synaptic F-actin, analyzed the hippocampal F-actin/G-actin (F/G) ratio and pCofilin, and evaluated the number of hippocampal neurons and pre/postsynaptic markers in pilocarpine-induced status epilepticus mice with or without administration of dexamethasone (DEX). We found that the latency of Stage 3 seizures increased, the mortality decreased, the damage to the synaptic F-actin cytoskeleton in the hippocampal subfields was significantly attenuated, and a greater number of postsynaptic structures were retained in the hippocampal subfields after treatment with DEX. These results indicate that treatment with dexamethasone stabilizes the synaptic F-actin cytoskeleton and reduces the damage to the brain due to SE. This approach is expected to be beneficial in alleviating delayed neuron damage and the process of epileptogenesis.


Assuntos
Citoesqueleto de Actina/genética , Dexametasona/farmacologia , Hipocampo/metabolismo , Estado Epiléptico/tratamento farmacológico , Actinas/genética , Animais , Modelos Animais de Doenças , Hipocampo/patologia , Humanos , Camundongos , Neurônios/metabolismo , Neurônios/patologia , Pilocarpina/toxicidade , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/genética , Estado Epiléptico/patologia
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