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1.
Artigo em Inglês | MEDLINE | ID: mdl-38985217

RESUMO

We aimed to investigate the predictive value of left atrium (LA) and left ventricle (LV) longitudinal strain derived by CMR-FT early after ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (pPCI). Patients with STEMI who received pPCI and completed CMR within the following week were enrolled. LA and LV longitudinal strain parameters were derived from cine CMR by FT; conventional CMR indexes were also performed. The primary endpoint was the occurrence of major cardiovascular adverse events (MACE), defined as a composite of death, reinfarction, and congestive heart failure (HF). 276 participants (median age, 57 years, IQR, 48-66 years; 85% men) were included in this study. CMR was usually completed on the 5 (IQR,4-7) days after pPCI. During a median follow-up of 16 months, MACE occurred in 35 (12.7%) participants. Multivariable Cox regression analysis showed that LA conduit strain (HR 0.91, 95%CI: 0.84, 0.98, p = 0.013) and LV global longitudinal strain (HR 1.17, 95%CI: 1.03, 1.34, p = 0.016) remained independently associated with MACE. Participants with impaired LA conduit strain (≤ 12.8%) and LV global longitudinal strain (> -13.1%) had a higher risk of MACE than those with preserved. Longitudinal strain of LA and LV could provide independent prognostic information in STEMI patients, and comprehensive assessment of Left atrial and ventricular longitudinal strain significantly improved the prognosis.

2.
Plant Cell Environ ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963294

RESUMO

NAC-domain transcription factors (TFs) are plant-specific transcriptional regulators playing crucial roles in plant secondary cell wall (SCW) biosynthesis. SCW is important for plant growth and development, maintaining plant morphology, providing rigid support, ensuring material transportation and participating in plant stress responses as a protective barrier. However, the molecular mechanisms underlying SCW in eggplant have not been thoroughly explored. In this study, the NAC domain TFs SmNST1 and SmNST2 were cloned from the eggplant line 'Sanyue qie'. SmNST1 and SmNST2 expression levels were the highest in the roots and stems. Subcellular localization analysis showed that they were localized in the cell membrane and nucleus. Their overexpression in transgenic tobacco showed that SmNST1 promotes SCW thickening. The expression of a set of SCW biosynthetic genes for cellulose, xylan and lignin, which regulate SCW formation, was increased in transgenic tobacco. Bimolecular fluorescence and luciferase complementation assays showed that SmNST1 interacted with SmNST2 in vivo. Yeast one-hybrid, electrophoretic mobility shift assay (EMSA) and Dual-luciferase reporter assays showed that SmMYB26 directly bound to the SmNST1 promoter and acted as an activator. SmNST1 and SmNST2 interact with the SmMYB108 promoter and repress SmMYB108 expression. Altogether, we showed that SmNST1 positively regulates SCW formation, improving our understanding of SCW biosynthesis transcriptional regulation.

3.
ACS Biomater Sci Eng ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39042061

RESUMO

Meniscal injuries are highly correlated with osteoarthritis (OA) onset and progression. Although meniscal allograft transplantation (MAT) is a therapeutic option to restore meniscal anatomy, a shortage of donor material and the donor-derived infectious risk may be concerns in clinics. This review summarizes the literature reporting meniscus repair status in preclinical models and clinical practice using allografts or synthetic grafts. The advantages and limitations of biodegradable polymer-based meniscal scaffolds, applied in preclinical studies, are discussed. Then, the long-term treatment outcomes of patients with allografts or commercial synthetic scaffolds are compared. A total of 47 studies are included in our network meta-analysis. Compared with the meniscal allografts, the commercial synthetic products significantly improved clinical treatment outcomes in terms of the Knee Injury and Osteoarthritis Outcome Score (KOOS), Visual Analog Scale (VAS) scores, and Lysholm scores. In addition, development strategies for the next generation of novel synthetic scaffolds are proposed through optimization of structural design and fabrication, and selection of cell sources, external stimuli, and active ingredients. This review may inspire researchers and surgeons to design and fabricate clinic-orientated grafts with improved treatment outcomes.

4.
Anal Methods ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38973656

RESUMO

A fluorescent sensor for highly selective and ultrasensitive detection of acetylsalicylic acid (ASA), succinic acid (SA), and ascorbic acid (AA) was reported. The water-soluble fluorescent ligand salicylic acid (Sal) was generated through catalyzing ASA by the hydrolase activity of zeolitic-imidazolate framework-8 (ZIF-8) or natural esterase (Est). The Sal can coordinate with 2-methylimidazole (2-MIm) and Ln(III) to form a fluorescent lanthanide coordination polymer (LCP), which has a fluorescence emission peak with the maximum wavelength at 412 nm (the excitation wavelength at 300 nm). Therefore, the detection of ASA can be achieved through the fluorescence intensity changes of LCPs in the system, which has comparable sensitivity and good selectivity (linear range of 0.031-1.00 mM and LODs of 11.72 and 3.22 µM) as compared to a direct reaction between Est/ZIF-8 and ASA for detecting ASA (linear range of 0.05-1.20 mM and limits of detection (LODs) of 4.43 and 4.58 µM). Furthermore, upon the addition of SA and AA, the fluorescence intensity of the reaction system can be enhanced and weakened through changing the energy resonance transfer pathways and affecting the enzymatic reaction process, respectively, realizing their sensitive and selective fluorescence detection. The established fluorescent sensors can work well in a wide linear range of SA concentrations from 0 to 2.50 mM (Est-based reaction system) and 0 to 1.50 mM (ZIF-8-based reaction system) with the LODs of 0.032 and 0.028 mM, respectively. The linear ranges of AA concentrations are from 0.0078 to 0.25 mM (Est-based reaction system) and 0.0078 to 0.13 mM (ZIF-8-based reaction system) with the LODs of 2.54 and 3.80 µM, respectively. The established sensors were successfully used in the detection of SA in rabbit plasma, with a recovery of 84.0%-98.7%. Additionally, the contents of ASA in Aspirin Enteric-Coated tablets and AA in vitamin C tablets were also determined by the developed methods.

5.
Nat Commun ; 15(1): 5729, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977723

RESUMO

Risk prediction for subsequent cardiovascular events remains an unmet clinical issue in patients with coronary artery disease. We aimed to investigate prognostic metabolic biomarkers by considering both shared and distinct metabolic disturbance associated with the composite and individual cardiovascular events. Here, we conducted an untargeted metabolomics analysis for 333 incident cardiovascular events and 333 matched controls. The cardiovascular events were designated as cardiovascular death, myocardial infarction/stroke and heart failure. A total of 23 shared differential metabolites were associated with the composite of cardiovascular events. The majority were middle and long chain acylcarnitines. Distinct metabolic patterns for individual events were revealed, and glycerophospholipids alteration was specific to heart failure. Notably, the addition of metabolites to clinical markers significantly improved heart failure risk prediction. This study highlights the potential significance of plasma metabolites on tailed risk assessment of cardiovascular events, and strengthens the understanding of the heterogenic mechanisms across different events.


Assuntos
Biomarcadores , Doença da Artéria Coronariana , Metabolômica , Humanos , Doença da Artéria Coronariana/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Biomarcadores/sangue , Infarto do Miocárdio/sangue , Carnitina/sangue , Carnitina/análogos & derivados , Carnitina/metabolismo , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/metabolismo , Prognóstico , Medição de Risco , Estudos de Casos e Controles , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/metabolismo , Metaboloma , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/metabolismo , Fatores de Risco
7.
One Earth ; 7(6): 1044-1055, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-39036466

RESUMO

The western United States is home to most of the nation's oil and gas production and, increasingly, wildfires. We examined historical threats of wildfires for oil and gas wells, the extent to which wildfires are projected to threaten wells as climate change progresses, and exposure of human populations to these wells. From 1984-2019, we found that cumulatively 102,882 wells were located in wildfire burn areas, and 348,853 people were exposed (resided ≤ 1 km). During this period, we observed a five-fold increase in the number of wells in wildfire burn areas and a doubling of the population within 1 km of these wells. These trends are projected to increase by late century, likely threatening human health. Approximately 2.9 million people reside within 1 km of wells in areas with high wildfire risk, and Asian, Black, Hispanic, and Native American people have disproportionately high exposure to wildfire-threatened wells.

8.
Vet Res ; 55(1): 82, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937820

RESUMO

Respiratory diseases constitute a major health problem for ruminants, resulting in considerable economic losses throughout the world. Parainfluenza type 3 virus (PIV3) is one of the most important respiratory pathogens of ruminants. The pathogenicity and phylogenetic analyses of PIV3 virus have been reported in sheep and goats. However, there are no recent studies of the vaccination of sheep or goats against PIV3. Here, we developed a purified inactivated ovine parainfluenza virus type 3 (OPIV3) vaccine candidate. In addition, we immunized sheep with the inactivated OPIV3 vaccine and evaluated the immune response and pathological outcomes associated with OPIV3 TX01 infection. The vaccinated sheep demonstrated no obvious symptoms of respiratory tract infection, and there were no gross lesions or pathological changes in the lungs. The average body weight gain significantly differed between the vaccinated group and the control group (P < 0.01). The serum neutralization antibody levels rapidly increased in sheep post-vaccination and post-challenge with OPIV3. Furthermore, viral shedding in nasal swabs and viral loads in the lungs were reduced. The results of this study suggest that vaccination with this candidate vaccine induces the production of neutralizing antibodies and provides significant protection against OPIV3 infection. These results may be helpful for further studies on prevention and control strategies for OPIV3 infections.


Assuntos
Infecções por Respirovirus , Doenças dos Ovinos , Vacinas de Produtos Inativados , Vacinas Virais , Animais , Ovinos , Infecções por Respirovirus/veterinária , Infecções por Respirovirus/prevenção & controle , Infecções por Respirovirus/virologia , Infecções por Respirovirus/imunologia , Vacinas de Produtos Inativados/imunologia , Doenças dos Ovinos/prevenção & controle , Doenças dos Ovinos/virologia , Doenças dos Ovinos/imunologia , Vacinas Virais/imunologia , Respirovirus/imunologia , Imunogenicidade da Vacina , Vacinação/veterinária
9.
J Cancer Res Clin Oncol ; 150(6): 314, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38907739

RESUMO

PURPOSE: Leukemia-associated fusion genes are closely related to the occurrence, development, diagnosis, and treatment of leukemia. DNA microarrays and second-generation sequencing have discovered multiple B-ALL fusion genes. We identified a novel MEF2C::SS18L1 fusion gene in a child diagnosed with B-ALL. This study investigates the oncogenicity and prognosis of this fusion gene in B-ALL. METHODS: A child with B-ALL who has a MEF2C::SS18L1 fusion is reported as a newly discovered case. Compared the breakpoints, structural domains, clinical phenotypes, and differential expression genes of MEF2C::SS18L1 and MEF2D::SS18.Using "ONCOFUSE" software, the carcinogenicity of MEF2C::SS18L1 is predicted. Using whole transcriptome sequencing, we analyze the breakpoints and the secondary structure of the fusion protein. Further, we compared the structures, differentially expressed genes, and clinical phenotypes of MEF2D and MEF2C fusion genes by DESeq, GO functional enrichment, and flow cytometry immunophenotyping analysis. RESULTS: Whole transcriptome sequencing identified a MEF2C::SS18L1 fusion transcript in a 3-year-old child with B-ALL. The MADS box, MEF structural domain, HJURP_C structural domain, and TAD I structural domain of MEF2C, and the QPGY structural domain of SS18L1, make up the fusion protein. "Oncofuse" found a 0.99 Bayesian probability that the fusion gene drives cancer. The breakpoint positions, fusion protein secondary structures, differentially expressed genes, and clinical characteristics of this patient were identical to those with MEF2D::SS18 fusion gene. CONCLUSION: We identified a novel MEF2C::SS18L1 fusion gene in childhood ALL, which shares similar structural and clinical characteristics with MEF2D::SS18. Further studies with more samples should be conducted in future.


Assuntos
Fatores de Transcrição MEF2 , Proteínas de Fusão Oncogênica , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Fatores de Transcrição MEF2/genética , Proteínas de Fusão Oncogênica/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética
10.
BMC Med ; 22(1): 223, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38831366

RESUMO

BACKGROUND: The trajectory of attention-deficit hyperactivity disorder (ADHD) symptoms in children and adolescents, encompassing descending, stable, and ascending patterns, delineates their ADHD status as remission, persistence or late onset. However, the neural and genetic underpinnings governing the trajectory of ADHD remain inadequately elucidated. METHODS: In this study, we employed neuroimaging techniques, behavioral assessments, and genetic analyses on a cohort of 487 children aged 6-15 from the Children School Functions and Brain Development project at baseline and two follow-up tests for 1 year each (interval 1: 1.14 ± 0.32 years; interval 2: 1.14 ± 0.30 years). We applied a Latent class mixed model (LCMM) to identify the developmental trajectory of ADHD symptoms in children and adolescents, while investigating the neural correlates through gray matter volume (GMV) analysis and exploring the genetic underpinnings using polygenic risk scores (PRS). RESULTS: This study identified three distinct trajectories (ascending-high, stable-low, and descending-medium) of ADHD symptoms from childhood through adolescence. Utilizing the linear mixed-effects (LME) model, we discovered that attention hub regions served as the neural basis for these three developmental trajectories. These regions encompassed the left anterior cingulate cortex/medial prefrontal cortex (ACC/mPFC), responsible for inhibitory control; the right inferior parietal lobule (IPL), which facilitated conscious focus on exogenous stimuli; and the bilateral middle frontal gyrus/precentral gyrus (MFG/PCG), accountable for regulating both dorsal and ventral attention networks while playing a crucial role in flexible modulation of endogenous and extrinsic attention. Furthermore, our findings revealed that individuals in the ascending-high group exhibited the highest PRS for ADHD, followed by those in the descending-medium group, with individuals in the stable-low group displaying the lowest PRS. Notably, both ascending-high and descending-medium groups had significantly higher PRS compared to the stable-low group. CONCLUSIONS: The developmental trajectory of ADHD symptoms in the general population throughout childhood and adolescence can be reliably classified into ascending-high, stable-low, and descending-medium groups. The bilateral MFG/PCG, left ACC/mPFC, and right IPL may serve as crucial brain regions involved in attention processing, potentially determining these trajectories. Furthermore, the ascending-high pattern of ADHD symptoms exhibited the highest PRS for ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Humanos , Transtorno do Deficit de Atenção com Hiperatividade/genética , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Criança , Adolescente , Masculino , Feminino , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Encéfalo/crescimento & desenvolvimento , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Neuroimagem , Estudos de Coortes
11.
Comput Methods Programs Biomed ; 254: 108284, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38924799

RESUMO

BACKGROUND: Coronary perfusion pressure (CPP) indicates spontaneous return of circulation and is recommended for high-quality cardiopulmonary resuscitation (CPR). This study aimed to investigate a method for non-invasive estimation of CPP using electrocardiography (ECG) and photoplethysmography (PPG) during CPR. METHODS: Nine pigs were used in this study. ECG, PPG, invasive arterial blood pressure (ABP), and right atrial pressure (RAP) signals were simultaneously recorded. The CPPs were estimated using three datasets: (a) ECG, (b) PPG, and (c) ECG and PPG, and were compared with invasively measured CPPs. Four machine-learning algorithms, namely support vector regression, random forest (RF), K-nearest neighbor, and gradient-boosted regression tree, were used for estimation of CPP. RESULTS: The RF model with a combined ECG and PPG dataset achieved better estimation of CPP than the other algorithms. Specifically, the mean absolute error was 4.49 mmHg, the root mean square error was 6.15 mm Hg, and the adjusted R2 was 0.75. A strong correlation was found between the non-invasive estimation and invasive measurement of CPP (r = 0.88), which supported our hypothesis that machine-learning-based analysis of ECG and PPG parameters can provide a non-invasive estimation of CPP for CPR. CONCLUSIONS: This study proposes a novel estimation of CPP using ECG and PPG with machine-learning-based algorithms. Non-invasively estimated CPP showed a high correlation with invasively measured CPP and may serve as an easy-to-use physiological indicator for high-quality CPR treatment.

12.
Biomed Chromatogr ; 38(7): e5885, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38736272

RESUMO

Zhujing pill (ZP) is a famous Chinese herbal formula that has been widely used to treat diabetic retinopathy, macular degeneration, retinitis pigmentosa and other fundus lesions. In this study, the material basis and mechanism of ZP in the treatment of fundus lesions were evaluated via the high-performance liquid chromatography fingerprint, ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry, network pharmacology and molecular docking. A total of 32 common components were found and 31 components were identified in 15 batches of ZP samples. Moreover, 134 common key targets and 17 putative active components that are connected to fundus lesions were identified. Molecular docking revealed that quercetin, kaempferol, isorhamnetin, 5-O-feruloylquinic acid, plantagoside and 2'-acetylacteoside have the ability to interact with the core targets such as AKT1, TP53, TNF, IL-6 and Jun. Our findings revealed that the therapeutic effects of ZP on fundus lesions are mediated by multiple components, targets and pathways, including at least six active ingredients and 11 targets. The study provides new ideas for further research on the material basis and mechanisms of traditional Chinese medicine prescriptions.


Assuntos
Medicamentos de Ervas Chinesas , Simulação de Acoplamento Molecular , Farmacologia em Rede , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Espectrometria de Massas/métodos
13.
Environ Res ; 257: 119232, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38810823

RESUMO

Long-term particulate matter with aerodynamic diameters ≤2.5 µm (PM2.5) exposure has been associated with the occurrence of acute coronary syndrome (ACS). However, the impact of PM2.5 exposure and its components on the severity of angina pectoris and disease-related health status in patients hospitalized for ACS is understudied. To assess the association between long-term exposure to PM2.5 components and the angina pectoris severity in ACS patients, as well as the modification effects of genetic factors and disease history in north China. During 2017-2019, 6729 ACS patients were collected in Shandong Province and Beijing, with their angina pectoris severity evaluated using Seattle Angina Questionnaire (SAQ). The 0-3 years' average concentrations of PM2.5 and its five major components were assigned to each patient's residential address. Linear mixed-effects model, weighted quantile regression, and quantile g-computation were used to estimate the effects of both single and joint associations between PM2.5 components and SAQ scores. The interactive effect was estimated by polygenic risk scores and disease history. For each interquartile range increase in PM2.5, the overall SAQ score changed by -3.71% (95%CI: -4.54% to -2.88%), with score of angina stability more affected than angina frequency and other dimensions of angina pectoris severity. Sulfate and ammonium were major contributors to the effect of PM2.5 exposure. Significant modification effect was only observed for disease history, especially for the dimension of physical limitation. Among a series of pre-existing diseases, patients with a family history of coronary artery disease, previous percutaneous coronary intervention or coronary artery bypass grafting, and stroke were more susceptible to PM2.5 exposure than others. Greater exposure to PM2.5 is associated with more serious angina pectoris and worse disease-related health status in ACS patients. Public health and clinical priority should be given to cutting down key effective components and protecting highly vulnerable individuals.


Assuntos
Síndrome Coronariana Aguda , Poluentes Atmosféricos , Angina Pectoris , Predisposição Genética para Doença , Material Particulado , Humanos , Síndrome Coronariana Aguda/genética , Síndrome Coronariana Aguda/epidemiologia , Material Particulado/análise , Material Particulado/toxicidade , Material Particulado/efeitos adversos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Angina Pectoris/epidemiologia , Angina Pectoris/genética , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Exposição Ambiental/efeitos adversos , China/epidemiologia , Nível de Saúde
14.
Exp Eye Res ; 244: 109937, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38782179

RESUMO

Sjögren's syndrome (SS) dry eye can cause ocular surface inflammation and lacrimal gland (LG) damage, leading to discomfort and potential vision problems. The existing treatment options for SS dry eye are currently constrained. We investigated the possible therapeutic effect and the underlying mechanism of AS101 in autoimmune dry eye. AS101 was injected subconjunctivally into a rabbit model of autoimmune dacryoadenitis and its therapeutic effects were determined by evaluating clinical and histological scores. The expressions of effector T cells (Teff)/regulatory T cells (Treg)-related transcription factors and cytokines, inflammation mediators, and transcription factor NFATc2 were measured by quantitative real-time PCR and/or Western blot both in vivo and in vitro. Additionally, the role of NFATc2 in the immunomodulatory effects of AS101 on T cells was explored by co-culturing activated peripheral blood lymphocytes (PBLs) transfected with NFATc2 overexpression lentiviral plasmid with AS101. AS101 treatment potently ameliorated the clinical severity and reduced the inflammation of LG. Further investigation revealed that AS101 treatment led to decreased expression of Th1-related genes (T-bet and IFN-γ) and Th17-related genes (RORC, IL-17A, IL-17F, and GM-CSF) and increased expression of Treg-related gene Foxp3 in vivo and in vitro. Meanwhile, AS101 suppressed the expression of TNF-α, IL-1ß, IL-23, IL-6, MMP-2, and MMP-9. Mechanistically, AS101 downregulated the expression of NFATc2 in inflamed LGs. Overexpression of NFATc2 in activated PBLs partially blunted the effect of AS101 on Teff suppression and Treg promotion. In conclusion, AS101 is a potential regulator of Teff/Treg cell balance and could be an effective treatment agent for SS dry eye.


Assuntos
Dacriocistite , Fatores de Transcrição NFATC , Síndrome de Sjogren , Animais , Feminino , Coelhos , Doenças Autoimunes/imunologia , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/metabolismo , Western Blotting , Citocinas/metabolismo , Dacriocistite/tratamento farmacológico , Dacriocistite/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica , Aparelho Lacrimal/metabolismo , Aparelho Lacrimal/patologia , Fatores de Transcrição NFATC/metabolismo , Fatores de Transcrição NFATC/genética , Reação em Cadeia da Polimerase em Tempo Real , Linfócitos T Reguladores/imunologia , Síndrome de Sjogren/tratamento farmacológico
15.
Angew Chem Int Ed Engl ; : e202403333, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38787684

RESUMO

Numerous studies have shown a fact that phase transformation and/or reconstruction are likely to occur and play crucial roles in electrochemical scenarios. Nevertheless, a decisive factor behind the diverse photoelectrochemical activity and selectivity of various copper/silicon photoelectrodes is still largely debated and missing in the community, especially the possibly dynamic behaviors of metal catalyst/semiconductor interface. Herein, through in situ X-ray absorption spectroscopy and transmission electron microscope, a model system of Cu nanocrystals with well-defined facets on black p-type silicon (BSi) is unprecedentedly demonstrated to reveal the dynamic phase transformation of forming irreversible silicide at Cu nanocrystal-BSi interface during photoelectrocatalysis, which is validated to originate from the atomic interdiffusion between Cu and Si driven by light-induced dynamic activation process. Significantly, the adaptive junction at Cu-Si interface is activated by an expansion of interatomic Cu-Cu distance for CO2 electroreduction, which efficiently restricts the C-C coupling pathway but strengthens the bonding with key intermediate of *CHO for CH4 yield, resulting in a remarkable 16-fold improvement in the product ratio of CH4/C2 products and an intriguing selectivity switch. This work offers new insights into dynamic structural transformations of metal/semiconductor junction and design of highly efficient catalysts toward photosynthesis.

16.
Biomed Mater ; 19(4)2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38815612

RESUMO

Magnesium (Mg) has gained widespread recognition as a potential revolutionary orthopedic biomaterial. However, whether the biodegradation of the Mg-based orthopedic implants would pose a risk to patients with chronic kidney disease (CKD) remains undetermined as the kidney is a key organ regulating mineral homeostasis. A rat CKD model was established by a 5/6 subtotal nephrectomy approach, followed by intramedullary implantation of three types of pins: stainless steel, high pure Mg with high corrosion resistance, and the Mg-Sr-Zn alloy with a fast degradation rate. The long-term biosafety of the biodegradable Mg or its alloys as orthopedic implants were systematically evaluated. During an experimental period of 12 weeks, the implantation did not result in a substantial rise of Mg ion concentration in serum or major organs such as hearts, livers, spleens, lungs, or kidneys. No pathological changes were observed in organs using various histological techniques. No significantly increased iNOS-positive cells or apoptotic cells in these organs were identified. The biodegradable Mg or its alloys as orthopedic implants did not pose an extra health risk to CKD rats at long-term follow-up, suggesting that these biodegradable orthopedic devices might be suitable for most target populations, including patients with CKD.


Assuntos
Implantes Absorvíveis , Ligas , Magnésio , Insuficiência Renal Crônica , Animais , Magnésio/química , Ligas/química , Ratos , Insuficiência Renal Crônica/terapia , Insuficiência Renal Crônica/metabolismo , Masculino , Ratos Sprague-Dawley , Materiais Biocompatíveis/química , Teste de Materiais , Rim/metabolismo , Rim/patologia , Aço Inoxidável/química , Corrosão
17.
J Biol Chem ; 300(6): 107382, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38763337

RESUMO

ASCT2 (alanine serine cysteine transporter 2), a member of the solute carrier 1 family, mediates Na+-dependent exchange of small neutral amino acids across cell membranes. ASCT2 was shown to be highly expressed in tumor cells, making it a promising target for anticancer therapies. In this study, we explored the binding mechanism of the high-affinity competitive inhibitor L-cis hydroxyproline biphenyl ester (Lc-BPE) with ASCT2, using electrophysiological and rapid kinetic methods. Our investigations reveal that Lc-BPE binding requires one or two Na+ ions initially bound to the apo-transporter with high affinity, with Na1 site occupancy being more critical for inhibitor binding. In contrast to the amino acid substrate bound form, the final, third Na+ ion cannot bind, due to distortion of its binding site (Na2), thus preventing the formation of a translocation-competent complex. Based on the rapid kinetic analysis, the application of Lc-BPE generated outward transient currents, indicating that despite its net neutral nature, the binding of Lc-BPE in ASCT2 is weakly electrogenic, most likely because of asymmetric charge distribution within the amino acid moiety of the inhibitor. The preincubation with Lc-BPE also led to a decrease of the turnover rate of substrate exchange and a delay in the activation of substrate-induced anion current, indicating relatively slow Lc-BPE dissociation kinetics. Overall, our results provide new insight into the mechanism of binding of a prototypical competitive inhibitor to the ASCT transporters.


Assuntos
Sistema ASC de Transporte de Aminoácidos , Antígenos de Histocompatibilidade Menor , Sistema ASC de Transporte de Aminoácidos/metabolismo , Sistema ASC de Transporte de Aminoácidos/antagonistas & inibidores , Sistema ASC de Transporte de Aminoácidos/genética , Sistema ASC de Transporte de Aminoácidos/química , Cinética , Antígenos de Histocompatibilidade Menor/metabolismo , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/química , Humanos , Sódio/metabolismo , Sódio/química , Animais , Ligação Competitiva
18.
Org Lett ; 26(22): 4797-4802, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38796776

RESUMO

Reported herein is a novel radical decarboxylation-initiated SH2' reaction of ß,ß-difluoroenol sulfonates. This transformation is characterized by mild reaction conditions, a broad substrate scope, and late-stage modification of drug molecules, providing general and mechanistically distinct access to bioactive and synthetically versatile α,α-difluoroketones. Preliminary mechanistic studies demonstrate that this reaction proceeds through a succession of silver-mediated decarboxylative radical generation and radical-addition-induced ß-elimination of the sulfonyl radical.

19.
Biol Psychiatry ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38718879

RESUMO

BACKGROUND: The right middle frontal gyrus (MFG) has been proposed as a convergence site for the dorsal attention network (DAN) and ventral attention network (VAN), regulating both networks and enabling flexible modulation of attention. However, it is unclear whether the connections between the right MFG and these networks can predict changes in attention-deficit/hyperactivity disorder (ADHD) symptoms. METHODS: This study used data from the Children School Functions and Brain Development project (N = 713, 56.2% boys). Resting-state functional magnetic resonance imaging was employed to analyze the connections of the right MFG with the DAN/VAN; connectome-based predictive modeling was applied for longitudinal prediction, and ADHD polygenic risk scores were used for genetic analysis. RESULTS: ADHD symptoms were associated with the connections between the right MFG and DAN subregion, including the frontal eye field, as well as the VAN subregions, namely the inferior parietal lobule and inferior frontal gyrus. Furthermore, these connections of the right MFG with the frontal eye field, the inferior parietal lobule, and the inferior frontal gyrus could significantly predict changes in ADHD symptoms over 1 year and mediate the prediction of ADHD symptom changes by polygenic risk scores for ADHD. Finally, the validation samples confirmed that the functional connectivity between the right MFG and the frontal eye field/inferior parietal lobule in patients with ADHD was significantly weaker than that in typically developing control participants, and this difference disappeared after medication. CONCLUSIONS: The connection of the right MFG with the DAN and VAN can serve as a predictive indicator for changes in ADHD symptoms over the following year, while also mediating the prediction of ADHD symptom changes by a polygenic risk score for ADHD. These findings hold promise as potential biomarkers for early identification of children who are at risk of developing ADHD.

20.
EMBO Mol Med ; 16(7): 1675-1703, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38806641

RESUMO

Profibrotic proximal tubules (PT) were identified as a unique phenotype of proximal tubule cells (PTCs) in renal fibrosis by single-cell RNA sequencing (scRNA-seq). Controlling the process of renal fibrosis requires understanding how to manage the S1 subset's branch to the S3 subset rather than to the profibrotic PT subset. Insulin-induced gene 1 (Insig1) is one of the branch-dependent genes involved in controlling this process, although its role in renal fibrosis is unknown. Here, we discovered that tubular Insig1 deficiency, rather than fibroblast Insig1 deficiency, plays a detrimental role in the pathogenesis of renal fibrosis in vivo and in vitro. Overexpression of Insig1 profoundly inhibited renal fibrosis. Mechanistically, Insig1 deletion in PTCs boosted SREBP1 nuclear localization, increasing Aldh1a1 transcriptional activity, causing excessive NAD+ consumption and ER enlargement, as well as accelerating renal fibrosis. We also identified nicardipine as a selective inhibitor of Aldh1a1, which could restore NAD+ and maintain ER homeostasis, as well as improve renal fibrosis. Together, our findings support tubular Insig1 as a new therapeutic target for chronic kidney disease (CKD).


Assuntos
Fibrose , Proteínas de Membrana , NAD , Animais , Camundongos , NAD/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Túbulos Renais Proximais/patologia , Túbulos Renais Proximais/metabolismo , Masculino , Humanos , Camundongos Endogâmicos C57BL , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética
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