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1.
Nano Lett ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38843402

RESUMO

High-entropy alloys (HEAs) have garnered considerable attention as promising nanocatalysts for effectively utilizing Pt in catalysis toward oxygen reduction reactions due to their unique properties. Nonetheless, there is a relative dearth of attention regarding the structural evolution of HEAs in response to electrochemical conditions. In this work, we propose a thermal reduction method to synthesize high entropy nanoparticles by leveraging the confinement effect and abundant nitrogen-anchored sites provided by pyrolyzed metal-organic frameworks (MOFs). Notably, the prepared catalysts exhibit enhanced activity accompanied by structural reconstruction during electrochemical activation, approaching 1 order of magnitude higher mass activity compared to Pt/C in oxygen reduction. Atomic-scale structural characterization reveals that abundant defects and single atoms are formed during the activation process, contributing to a significant boost in the catalytic performance for oxygen reduction reactions. This study provides deep insights into surface reconstruction engineering during electrochemical operations, with practical implications for fuel cell applications.

2.
J Lipid Res ; 65(3): 100514, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38309418

RESUMO

Human genetic evidence suggests a protective role of loss-of-function variants in 17-beta hydroxysteroid dehydrogenase 13 (HSD17B13) for liver fibrotic diseases. Although there is limited preclinical experimental data on Hsd17b13 antisense oligonucleotide (ASO) or siRNA in a fibrosis model, several ASO and siRNA approaches are being tested clinically as potential therapies for nonalcoholic steatohepatitis (NASH). The aim of this study was to assess the therapeutic potential of Hsd17b13 ASO in a preclinical advanced NASH-like hepatic fibrosis in vivo model. In vitro testing on primary hepatocytes demonstrated that Hsd17b13 ASO exhibited strong efficacy and specificity for knockdown of the Hsd17b13 gene. In choline-deficient, L-amino acid-defined, HFD (CDAHFD)-induced steatotic and fibrotic mice, therapeutic administration of Hsd17b13 ASO resulted in a significant and dose-dependent reduction of hepatic Hsd17b13 gene expression. The CDAHFD group exhibited considerably elevated liver enzyme levels, hepatic steatosis score, hepatic fibrosis, and increased fibrotic and inflammatory gene expression, indicating an advanced NASH-like hepatic fibrosis phenotype. Although Hsd17b13 ASO therapy significantly affected hepatic steatosis, it had no effect on hepatic fibrosis. Our findings demonstrate, for the first time, that Hsd17b13 ASO effectively suppressed Hsd17b13 gene expression both in vitro and in vivo, and had a modulatory effect on hepatic steatosis in mice, but did not affect fibrosis in the CDAHFD mouse model of NASH.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Camundongos , Modelos Animais de Doenças , Fígado/metabolismo , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/genética , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Oligonucleotídeos Antissenso/genética , Oligonucleotídeos Antissenso/farmacologia , Oligonucleotídeos Antissenso/uso terapêutico , RNA Interferente Pequeno/metabolismo
3.
Altern Ther Health Med ; 30(5): 136-140, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38743887

RESUMO

Objective: To investigate the molecular mechanism of sevoflurane affecting the development of the offspring's nervous system through the GABAAR/Sirt 1 pathway. Methods: Pregnant rats were obtained by mating females and males, and were randomly divided into 3 h sevoflurane (2.3% sevoflurane anesthesia for 3 h), 6 h sevoflurane (2.3% sevoflurane anesthesia for 6 h), Sirt-1 activator-SRT1720 (10 mg/kg SRT1720), 6 h sevoflurane+SRT1720 (10 mg/kg SRT1720) and control groups) group and control group, 31-day-old littermates were taken out and their learning and memory functions were examined by the water maze experiment; the heads were severed to remove the brains, and the kits were used to detect the levels of 5-HT and Ach in the brain tissue; the hippocampal tissues of the littermates were isolated, and neuronal damage in the hippocampal tissues was assessed by Nissen staining; neuronal apoptosis in the hippocampal tissues was detected by TUNEL staining; and GABAAR in the hippocampal tissues was detected by Western blot. GABAAR, Sirt-1, and apoptosis-related proteins (Caspase-3, BCL-2, BAX) in hippocampal tissue. Results: Compared with the control group, the 3 h sevoflurane group and the 6 h sevoflurane group neurons were arranged sparsely, the cells appeared to be swollen, the evasion latency, the apoptosis rate of neurons, the expression of Caspase-3, and BAX increased significantly, and the number of crossing the plateau, the level of 5-HT and Ach in the brain tissues, and the expression of GABAAR, Sirt-1, and BCL-2 were decreased significantly, and the differences existed between the groups (P < .5); compared with the 6 h sevoflurane group, neuronal morphological changes in the hippocampal tissue of the 6 h sevoflurane+SRT1720 group were improved, with a significant decrease in the evasion latency, neuronal apoptosis rate, expression of Caspase-3 and BAX, and a significant increase in the number of traversing platforms, brain tissue 5-HT, Ach level, GABAAR, Sirt-1, and BCL-2 expression (P < .5); compared with the SRT1720 group, the neurons in the 6 h sevoflurane + SRT1720 group were sparsely arranged, with a significant increase in evasion latency, neuronal apoptosis rate, caspase-3, BAX expression, and a significant decrease in the number of traversing platforms, brain tissue 5-HT, Ach level, GABAAR, Sirt-1, and BCL-2 expression (P < .5 ). Conclusion: Sevoflurane can affect the neurological development of rat offspring, which may be related to the inhibition of Sirt-1 expression.


Assuntos
Sevoflurano , Sirtuína 1 , Sevoflurano/farmacologia , Animais , Sirtuína 1/metabolismo , Ratos , Feminino , Gravidez , Anestésicos Inalatórios/farmacologia , Receptores de GABA-A/metabolismo , Receptores de GABA-A/efeitos dos fármacos , Masculino , Ratos Sprague-Dawley , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Apoptose/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
4.
Artigo em Inglês | MEDLINE | ID: mdl-39113542

RESUMO

Recent studies have reported increasing complexity in human immunodeficiency virus 1 (HIV-1) genotypes among men who have sex with men (MSM) in China. In an HIV-1 molecular epidemiological study conducted among MSM in Yunnan Province, China, we discovered that four samples could potentially represent a circulating recombinant form (CRF). In this study, we conducted further analysis on their nearly full-length genome (NFLG) sequences. The NFLG sequences formed a distinct monophyletic clade in the phylogenetic tree. Recombination analysis indicated that the four sequences were constructed upon the backbone of CRF149_01B, with the insertion of three CRF07_BC fragments. Consequently, they were designated as CRF150_cpx. Evolutionary analyses suggested that CRF150_cpx emerged between approximately 2014 and 2015. The identification of new CRFs not only deepens our understanding of HIV recombination but also aids in comprehending the prevalence and transmission history of HIV among specific populations.

5.
Front Plant Sci ; 15: 1384246, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601316

RESUMO

Introduction: Salt tolerance during seed germination is an important trait for direct seeding and low-cost rice production. Nevertheless, it is still not clear how seed germination under salt stress is regulated genetically. Methods: In this study, genome-wide association studies (GWAS) were performed to decipher the genetic basis of seed germination under salt stress using 541 rice varieties collected worldwide. Results and discussion: Three quantitative trait loci (QTLs) were identified including qGRG3-1 on chromosome 3, qGRG3-2 on chromosome 5, and qGRG4 on chromosome 4. Assessment of candidate genes in these loci for their responses to salt stress identified a TATA modulatory factor (OsTMF) in qGRG3-2. The expression of OsTMF was up-regulated in both roots and shoots after exposure to salt stress, and OsTMF knockout mutants exhibited delayed seed germination under salt stress. Haplotype analysis showed that rice varieties carrying OsTMF-Hap2 displayed elevated salt tolerance during seed germination. These results provide important knowledge and resources to improve rice seed germination under salt stress in the future.

6.
Sci Rep ; 14(1): 11506, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769108

RESUMO

The optimal design of groundwater circulation wells (GCWs) is challenging. The key to purifying groundwater using this technique is its proficiency and productivity. However, traditional numerical simulation methods are limited by long modeling times, random optimization schemes, and optimization results that are not comprehensive. To address these issues, this study introduced an innovative approach for the optimal design of a GCW using machine learning methods. The FloPy package was used to create and implement the MODFLOW and MODPATH models. Subsequently, the formulated models were employed to calculate the characteristic indicators of the effectiveness of the GCW operation, including the radius of influence (R) and the ratio of particle recovery (Pr). A detailed collection of 3000 datasets, including measures of operational efficiency and key elements in machine learning, was meticulously compiled into documents through model execution. The optimization models were trained and evaluated using multiple linear regression (MLR), artificial neural networks (ANN), and support vector machines (SVM). The models produced by the three approaches exhibited notable correlations between anticipated outcomes and datasets. For the optimal design of circulating well parameters, machine learning methods not only improve the optimization speed, but also expand the scope of parameter optimization. Consequently, these models were applied to optimize the configuration of the GCW at a site in Xi'an. The optimal scheme for R (Q = 293.17 m3/d, a = 6.09 m, L = 7.28 m) and optimal scheme for Pr (Q = 300 m3/d, a = 3.64 m, L = 1 m) were obtained. The combination of numerical simulations and machine learning is an effective tool for optimizing and predicting the GCW remediation effect.

7.
Am J Med Sci ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38992750

RESUMO

AIM: The present study was conducted to measure the expression of early growth response factor 3 (Egr3), inflammatory cytokines (IL-1ß, IL-6), vascular endothelial growth factor (VEGF) and NF-κB in patients with coronary artery disease (CAD) to investigate the relationships of these molecules and Egr3 gene expression. METHODS: We recruited 132 CAD patients and 63 healthy individuals. The expression levels of Egr3, VEGF, p50 and p65 were measured by reverse transcription quantitative polymerase chain reaction and the levels of Egr3, IL-1ß and IL-6 in patients serum and in human coronary artery endothelial cells (HCAECs) were measured by enzyme-linked immunosorbent assay (ELISAs) in CAD patients. HCAECs were treated with ox-LDL to establish an in vitro atherosclerosis model. An oil red O staining assay was used to assess the lipid droplet formation. A colloidal external lumen formed by Matrigel was used to test the migration of HCAECs. The expression of Egr3, VEGF and NF-κB was determined by Western blotting. RESULTS: The levels of serum Egr3 and IL-6 in the severe stenosis group were greater than those in the mild stenosis group and controls (p < 0.05). The level of serum IL-1ß in the severe stenosis group was greater than that in the control group (p < 0.05). Moreover, Egr3 expression was positively associated with IL-6 levels (r= 0.55, p < 0.001), IL-1ß levels (r=0.21, p=0.004) and the Gensini score (r=0.20, p=0.02). We also found that Egr3 expression was significantly greater in CAD patients than that in controls. And its expression was highest in the mild patients. The expression of VEGF, P50 and P65 was also greater in CAD patients. In the in vitro experiment, we found that the inhibition of Egr3 expression significantly reduced the expression levels of p50, p65, IL-6 and CRP. Moreover, the inhibition of Egr3 expression significantly reduced the lipid droplet formation and decreased capability of lumen formation. CONCLUSIONS: In the pathogenesis of atherosclerosis, Egr3 gene expression may induce the expression of inflammatory factors and lipid droplet formation and lumen formation, which could promote the atherosclerosis development.

8.
Signal Transduct Target Ther ; 9(1): 15, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38195689

RESUMO

Human microorganisms, including bacteria, fungi, and viruses, play key roles in several physiological and pathological processes. Some studies discovered that tumour tissues once considered sterile actually host a variety of microorganisms, which have been confirmed to be closely related to oncogenesis. The concept of intratumoural microbiota was subsequently proposed. Microbiota could colonise tumour tissues through mucosal destruction, adjacent tissue migration, and hematogenic invasion and affect the biological behaviour of tumours as an important part of the tumour microenvironment. Mechanistic studies have demonstrated that intratumoural microbiota potentially promote the initiation and progression of tumours by inducing genomic instability and mutations, affecting epigenetic modifications, promoting inflammation response, avoiding immune destruction, regulating metabolism, and activating invasion and metastasis. Since more comprehensive and profound insights about intratumoral microbiota are continuously emerging, new methods for the early diagnosis and prognostic assessment of cancer patients have been under examination. In addition, interventions based on intratumoural microbiota show great potential to open a new chapter in antitumour therapy, especially immunotherapy, although there are some inevitable challenges. Here, we aim to provide an extensive review of the concept, development history, potential sources, heterogeneity, and carcinogenic mechanisms of intratumoural microorganisms, explore the potential role of microorganisms in tumour prognosis, and discuss current antitumour treatment regimens that target intratumoural microorganisms and the research prospects and limitations in this field.


Assuntos
Microbiota , Neoplasias , Humanos , Neoplasias/genética , Neoplasias/terapia , Imunoterapia , Carcinogênese/genética , Transformação Celular Neoplásica , Microbiota/genética , Microambiente Tumoral/genética
9.
China CDC Wkly ; 6(27): 658-664, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-39027632

RESUMO

What is already known about this topic?: HIV transmission among serodiscordant couples remains a persistent issue in China. However, the practice of combining counseling with antiretroviral therapies (ART) to enhance ART adherence is not widely implemented or recommended in Chinese health guidelines. What is added by this report?: This randomized controlled trial suggests that increased follow-up, counseling, and awareness of HIV risk can enhance ART compliance, thereby maximizing treatment efficacy. What are the implications for public health practice?: Early testing and counseling of serodiscordant couples, following the identification of a human immunodeficiency virus (HIV) positive spouse, is crucial for initiating ART and reducing the risk of seroconversion in the uninfected partner. Implementing a combination of ART and adjunct counseling in China is advisable.

10.
Braz J Med Biol Res ; 57: e13409, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38958367

RESUMO

Tuberculosis (TB), caused by Mycobacterium tuberculosis, remains the leading cause of mortality by a single infectious agent in the world. M. tuberculosis infection could also result in clinical chronic infection, known as latent TB infection (LTBI). Compared to the current limited treatment, several subunit vaccines showed immunotherapeutic effects and were included in clinical trials. In this study, a subunit vaccine of Ag85B with a novel mucosal adjuvant c-di-AMP (Ag85B:c-di-AMP) was delivered intranasally to a persistent M. tuberculosis H37Ra infection mouse model, which also presented the asymptomatic characteristics of LTBI. Compared with Ag85B immunization, Ag85B:c-di-AMP vaccination induced stronger humoral immune responses, significantly higher CD4+ T cells recruitment, enhanced Th1/Th2/Th17 profile response in the lung, decreased pathological lesions of the lung, and reduced M. tuberculosis load in mice. Taken together, Ag85B:c-di-AMP mucosal route immunization provided an immunotherapeutic effect on persistent M. tuberculosis H37Ra infection, and c-di-AMP, as a promising potential mucosal adjuvant, could be further used in therapeutic or prophylactic vaccine strategies for persistent M. tuberculosis infection as well as LTBI.


Assuntos
Adjuvantes Imunológicos , Modelos Animais de Doenças , Mycobacterium tuberculosis , Vacinas contra a Tuberculose , Animais , Adjuvantes Imunológicos/administração & dosagem , Vacinas contra a Tuberculose/imunologia , Vacinas contra a Tuberculose/administração & dosagem , Mycobacterium tuberculosis/imunologia , Camundongos , Feminino , Antígenos de Bactérias/imunologia , Aciltransferases/imunologia , Vacinas de Subunidades Antigênicas/imunologia , Vacinas de Subunidades Antigênicas/administração & dosagem , Proteínas de Bactérias/imunologia , Tuberculose/imunologia , Tuberculose/prevenção & controle , Tuberculose Latente/imunologia , Camundongos Endogâmicos BALB C , Administração Intranasal
11.
Artigo em Inglês | MEDLINE | ID: mdl-38959124

RESUMO

The border areas of Yunnan Province in China are severely affected by human immunodeficiency virus (HIV). To investigate the risk of HIV transmission and assess the prevalence of pretreatment drug resistance (PDR) in the border area, blood samples were collected from individuals with newly reported HIV in 2021 in three border counties (Cangyuan, Gengma, and Zhenkang) in Yunnan Province. Among the 174 samples successfully genotyped, eight circulating recombinant forms (CRFs), two subtypes, and several unique recombinant forms (URFs) were identified. CRF08_BC (56.9%, 99/174), URFs (14.4%, 25/174), CRF01_AE (10.9%, 19/174), and CRF07_BC (8.0%, 14/174) were the main genotypes. CRF08_BC and URFs were detected more frequently in Chinese and Burmese individuals, respectively. CRF07_BC was found more frequently in men who have sex with men. The proportion of individuals detected in HIV-1 networks was only associated with case-reporting counties. When stratified by county, individuals aged ≤40 years in Cangyuan and ≥41 years in Gengma were more likely to be found in these networks. Furthermore, 93.8% (15/16) of the links in Cangyuan and 79.4% (50/63) of those in Gengma were located within their own counties. The prevalence of PDR to any antiretroviral drug, nucleoside reverse transcriptase inhibitors (NRTIs), and non-nucleoside reverse transcriptase inhibitors (NNRTIs) were 10% (17/170), 0.6% (1/170), and 9.4% (16/170), respectively. The most frequent resistance-associated mutations (RAMs) were V179D/VD/E/T (22.9%, 39/170) and E138A/G/K/R (13.5%, 23/170). In the molecular networks, six clusters shared common RAMs. HIV-1 genetics has become more diverse in border areas. HIV-1 molecular network analysis revealed the different characteristics of the HIV-1 epidemic in the border counties. The prevalence of PDR showed an upward trend, and the PDR to NNRTIs was close to the public response threshold. These findings provide information for the development of AIDS prevention and treatment strategies.

14.
Braz. j. med. biol. res ; 57: e13409, fev.2024. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1564163

RESUMO

Tuberculosis (TB), caused by Mycobacterium tuberculosis, remains the leading cause of mortality by a single infectious agent in the world. M. tuberculosis infection could also result in clinical chronic infection, known as latent TB infection (LTBI). Compared to the current limited treatment, several subunit vaccines showed immunotherapeutic effects and were included in clinical trials. In this study, a subunit vaccine of Ag85B with a novel mucosal adjuvant c-di-AMP (Ag85B:c-di-AMP) was delivered intranasally to a persistent M. tuberculosis H37Ra infection mouse model, which also presented the asymptomatic characteristics of LTBI. Compared with Ag85B immunization, Ag85B:c-di-AMP vaccination induced stronger humoral immune responses, significantly higher CD4+ T cells recruitment, enhanced Th1/Th2/Th17 profile response in the lung, decreased pathological lesions of the lung, and reduced M. tuberculosis load in mice. Taken together, Ag85B:c-di-AMP mucosal route immunization provided an immunotherapeutic effect on persistent M. tuberculosis H37Ra infection, and c-di-AMP, as a promising potential mucosal adjuvant, could be further used in therapeutic or prophylactic vaccine strategies for persistent M. tuberculosis infection as well as LTBI.

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