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1.
BMC Infect Dis ; 24(1): 511, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38773443

RESUMO

INTRODUCTION: This study aimed to analyze the risk factors associated with isoniazid-resistant and rifampicin-susceptible tuberculosis (Hr-TB) in adults. METHOD: The clinical data of 1,844 adult inpatients diagnosed with culture-positive pulmonary tuberculosis (PTB) in Nanjing Second Hospital from January 2019 and December 2021 were collected. All culture positive strain from the patient specimens underwent drug susceptibility testing (DST). Among them, 166 patients with Hr-TB were categorized as the Hr-TB group, while the remaining 1,678 patients were classified as having drug-susceptible tuberculosis (DS-TB). Hierarchical logistic regression was employed for multivariate analysis to identify variables associated with Hr-TB. RESULTS: Multivariate logistic regression analysis revealed that individuals with diabetes mellitus (DM) (OR 1.472, 95% CI 1.037-2.088, p = 0.030) and a history of previous tuberculosis treatment (OR 2.913, 95% CI 1.971-4.306, p = 0.000) were at higher risk of developing adult Hr-TB, with this risk being more pronounced in male patients. Within the cohort, 1,640 patients were newly treated, and among them, DM (OR 1.662, 95% CI 1.123-2.461, p = 0.011) was identified as risk factors for Hr-TB. CONCLUSIONS: Diabetes mellitus is a risk factor for Hr-TB in adults, and the contribution of diabetes as a risk factor was more pronounced in the newly treatment or male subgroup. And previous TB treatment history is also a risk factor for Hr-TB in adults.


Assuntos
Antituberculosos , Isoniazida , Mycobacterium tuberculosis , Rifampina , Tuberculose Pulmonar , Humanos , Masculino , Feminino , Fatores de Risco , Isoniazida/uso terapêutico , Isoniazida/farmacologia , Rifampina/uso terapêutico , Rifampina/farmacologia , Pessoa de Meia-Idade , Adulto , China/epidemiologia , Antituberculosos/uso terapêutico , Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/microbiologia , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Testes de Sensibilidade Microbiana , Idoso , Adulto Jovem , Estudos Retrospectivos , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/microbiologia
2.
Int J Med Sci ; 21(4): 765-774, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38464823

RESUMO

Introduction: Epidermal growth factor receptor (EGFR) mutation is common in Chinese patients with lung adenocarcinoma (LUAD). Brain metastases (BMs) is high and associated with poor prognosis. Identification of EGFR-mutant patients at high risk of developing BMs is important to reduce or delay the incidence of BMs. Currently, there is no literature on the prediction and modeling of EGFR brain metastasis at the proteinomics level. Methods: We conducted a retrospective study of BMs in postoperative recurrent LUAD with EGFR mutation in the First Affiliated Hospital of Guangzhou Medical University. Tissue proteomic analysis was applied in the primary tumors of resected LUAD in this study using liquid chromatography-mass spectrometry (LC-MS/MS). To identify potential markers for predicting LUAD BM, comparative analyses were performed on different groups to evaluate proteins associated with high risk of BMs. Results: A combination of three potential marker proteins was found to discriminate well between distal metastasis (DM) and local recurrence (LR) of postoperative LUAD with EGFR mutation. Gene Ontology (GO) analysis of significantly altered proteins between BM and non-BM (NBM) indicated that lipid metabolism and cell cycle-related pathways were involved in BMs of LUAD. And the enriched pathways correlated with BMs were found to be quite different in the comparison groups of postoperative adjuvant therapy, tyrosine kinase inhibitor (TKI), and chemotherapy groups. Finally, we developed a random forest algorithm model with eight proteins (RRS1, CPT1A, DNM1, SRCAP, MLYCD, PCID2, IMPAD1 and FILIP1), which showed excellent predictive value (AUC: 0.9401) of BM in patients with LUAD harboring EGFR mutation. Conclusions: A predictive model based on protein markers was developed to accurately predict postoperative BM in operable LUAD harboring EGFR mutation.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Neoplasias Encefálicas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/patologia , Proteômica , Estudos Retrospectivos , Cromatografia Líquida , Mutação , Recidiva Local de Neoplasia/genética , Espectrometria de Massas em Tandem , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/cirurgia , Adenocarcinoma/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/patologia , Receptores ErbB/metabolismo , Fatores de Risco , Proteínas Nucleares/genética
3.
Cancer Sci ; 114(10): 3924-3934, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37640025

RESUMO

We previously reported the results of a phase II trial of anti-PD-1 antibody plus anti-vascular endothelial growth factor receptor 2 inhibitors and eribulin in heavily pretreated advanced triple-negative breast cancer with a favorable objective response rate (ORR) of 37.0% (NCT04303741). Here we report updated survival outcomes and serum metabolite changes of the study. Proton nuclear magnetic resonance spectroscopy was used to detect metabolite dynamics and explore biomarkers for response. We found that treatment-sensitive patients had higher very low-density lipoprotein-related metabolite expression at baseline. A lipid proteomics model consisting of six metabolites predicted ORR and progression-free survival at 6 months with area under the receiver operating characteristic curves of 0.88 and 0.87, respectively. Serum asparagine and sarcosine concentrations were significantly higher after treatment in treatment-resistant patients. In conclusion, we constructed a model consisting of six metabolites to identify patients who benefit more from the triplet treatment, and asparagine and sarcosine may be associated with treatment resistance.

4.
PLoS Pathog ; 17(8): e1009758, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34379705

RESUMO

Since the pandemic of COVID-19 has intensely struck human society, small animal model for this infectious disease is in urgent need for basic and pharmaceutical research. Although several COVID-19 animal models have been identified, many of them show either minimal or inadequate pathophysiology after SARS-CoV-2 challenge. Here, we describe a new and versatile strategy to rapidly establish a mouse model for emerging infectious diseases in one month by multi-route, multi-serotype transduction with recombinant adeno-associated virus (AAV) vectors expressing viral receptor. In this study, the proposed approach enables profound and enduring systemic expression of SARS-CoV-2-receptor hACE2 in wild-type mice and renders them vulnerable to SARS-CoV-2 infection. Upon virus challenge, generated AAV/hACE2 mice showed pathophysiology closely mimicking the patients with severe COVID-19. The efficacy of a novel therapeutic antibody cocktail RBD-chAbs for COVID-19 was tested and confirmed by using this AAV/hACE2 mouse model, further demonstrating its successful application in drug development.


Assuntos
COVID-19 , Doenças Transmissíveis Emergentes , Modelos Animais de Doenças , Células 3T3 , Enzima de Conversão de Angiotensina 2/genética , Animais , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/uso terapêutico , COVID-19/imunologia , COVID-19/patologia , COVID-19/fisiopatologia , Chlorocebus aethiops , Dependovirus/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Transdução Genética , Células Vero
5.
J Org Chem ; 88(14): 10252-10256, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37406152

RESUMO

The skeletal editing of dibenzolactones to fluorenes by Ni- or Pd-catalyzed decarboxylation is reported. In contrast to previously reported intramolecular decarboxylative couplings, inductively electron-withdrawing ortho substituents on the aryl carboxylate moiety and metal additives are not required. The decarboxylation reaction proceeds cleanly and can be applied to the skeletal editing of a natural product analogue. Mechanistic observations are consistent with stabilization of the carboxylate-ligated Ni complex over the Ni-carboxylate ion pair, which is the key factor in promoting the challenging decarboxylation step in the catalytic cycle.

6.
Hum Brain Mapp ; 43(17): 5194-5209, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-35751844

RESUMO

Functional connectivity of the human brain, representing statistical dependence of information flow between cortical regions, significantly contributes to the study of the intrinsic brain network and its functional mechanism. To fully explore its potential in the early diagnosis of Alzheimer's disease (AD) using electroencephalogram (EEG) recordings, this article introduces a novel dynamical spatial-temporal graph convolutional neural network (ST-GCN) for better classification performance. Different from existing studies that are based on either topological brain function characteristics or temporal features of EEG, the proposed ST-GCN considers both the adjacency matrix of functional connectivity from multiple EEG channels and corresponding dynamics of signal EEG channel simultaneously. Different from the traditional graph convolutional neural networks, the proposed ST-GCN makes full use of the constrained spatial topology of functional connectivity and the discriminative dynamic temporal information represented by the 1D convolution. We conducted extensive experiments on the clinical EEG data set of AD patients and Healthy Controls. The results demonstrate that the proposed method achieves better classification performance (92.3%) than the state-of-the-art methods. This approach can not only help diagnose AD but also better understand the effect of normal ageing on brain network characteristics before we can accurately diagnose the condition based on resting-state EEG.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/diagnóstico por imagem , Eletroencefalografia , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos
7.
Hum Brain Mapp ; 43(2): 860-879, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34668603

RESUMO

Functional connectivity and effective connectivity of the human brain, representing statistical dependence and directed information flow between cortical regions, significantly contribute to the study of the intrinsic brain network and its functional mechanism. Many recent studies on electroencephalography (EEG) have been focusing on modeling and estimating brain connectivity due to increasing evidence that it can help better understand various brain neurological conditions. However, there is a lack of a comprehensive updated review on studies of EEG-based brain connectivity, particularly on visualization options and associated machine learning applications, aiming to translate those techniques into useful clinical tools. This article reviews EEG-based functional and effective connectivity studies undertaken over the last few years, in terms of estimation, visualization, and applications associated with machine learning classifiers. Methods are explored and discussed from various dimensions, such as either linear or nonlinear, parametric or nonparametric, time-based, and frequency-based or time-frequency-based. Then it is followed by a novel review of brain connectivity visualization methods, grouped by Heat Map, data statistics, and Head Map, aiming to explore the variation of connectivity across different brain regions. Finally, the current challenges of related research and a roadmap for future related research are presented.


Assuntos
Encéfalo/fisiologia , Conectoma , Aprendizado de Máquina , Rede Nervosa/fisiologia , Eletroencefalografia , Humanos
8.
J Biomed Sci ; 29(1): 49, 2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35799178

RESUMO

BACKGROUND: With the continuous emergence of new SARS-CoV-2 variants that feature increased transmission and immune escape, there is an urgent demand for a better vaccine design that will provide broader neutralizing efficacy. METHODS: We report an mRNA-based vaccine using an engineered "hybrid" receptor binding domain (RBD) that contains all 16 point-mutations shown in the currently prevailing Omicron and Delta variants. RESULTS: A booster dose of hybrid vaccine in mice previously immunized with wild-type RBD vaccine induced high titers of broadly neutralizing antibodies against all tested SARS-CoV-2 variants of concern (VOCs). In naïve mice, hybrid vaccine generated strong Omicron-specific neutralizing antibodies as well as low but significant titers against other VOCs. Hybrid vaccine also elicited CD8+/IFN-γ+ T cell responses against a conserved T cell epitope present in wild type and all VOCs. CONCLUSIONS: These results demonstrate that inclusion of different antigenic mutations from various SARS-CoV-2 variants is a feasible approach to develop cross-protective vaccines.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Anticorpos Amplamente Neutralizantes , COVID-19/prevenção & controle , Humanos , Camundongos , SARS-CoV-2/genética , Vacinas Sintéticas , Vacinas de mRNA
9.
Neuroradiology ; 64(1): 161-169, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34331546

RESUMO

PURPOSE: Perfusion imaging generates multimaps of ischemic tissues and is a proven decision-making tool in patients with acute ischemic stroke. However, the reliability of perfusion post-processing outcomes has been debated, given disparate results of various software applications, especially for patients with small ischemic core volume. This study was undertaken to compare ischemic volume estimates determined by imSTROKE (a software with new imaging protocol) and RAPID computer applications, respectively. METHODS: A total of 611 patients qualified for study, each having met inclusion and exclusion criteria of the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN trial). Subjects were examined by computed tomography perfusion (CTP) imaging (n = 349) or perfusion-weighted (PWI) and diffusion-weighted (DWI) imaging (n = 262). Ischemic volumes estimated by imSTROKE and RAPID applications were then compared. We used Bland-Altman analysis and intraclass correlation coefficients (ICCs) to ascertain agreement between applications. Accuracies of estimated core infarct and penumbra volumes were tested at specific thresholds (core: 25 mL, 50 mL, and 70 mL; penumbra: 45 mL, 90 mL, and 125 mL). RESULTS: Median core infarct volumes by imSTROKE and RAPID were 29.18 mL and 29.53 mL, respectively (ICC = 0.9880, 95% confidence interval [CI]: 0.9860-0.9898). Median penumbra volumes by imSTROKE and RAPID were 68.20 mL and 68.55 mL, respectively (ICC = 0.9885, 95% CI: 0.9865-0.9902). CONCLUSION: In estimating core infarct and penumbra volumes, imSTROKE and RAPID applications showed high-level agreement. For patients with small ischemic core volume, compared with RAPID, imSTROKE may have better sensitivity.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Encéfalo , Isquemia Encefálica/diagnóstico por imagem , Humanos , Perfusão , Imagem de Perfusão , Reprodutibilidade dos Testes , Software , Acidente Vascular Cerebral/diagnóstico por imagem
10.
J Asian Nat Prod Res ; 24(7): 679-684, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34292113

RESUMO

A new isocoumarin, penicimarin N (1), along with five known compounds (2-6), were isolated from the mangrove-derived fungus Penicillium sp. TGM112. The structure of 1 was elucidated on the basis of extensive spectroscopic data analysis, and the absolute configuration of 1 was determined by comparison of their circular dichroism (CD) spectra with the literature. The structures of known compounds were determined by comparison with the literature data. All the isolated compounds were examined for their antioxidant and α-glucosidase activities. Compound 1 showed strong antioxidant activity with the IC50 value of 1.0 mM, and 1 also exhibited moderate inhibitory activity against α-glucosidase with the IC50 value of 620 µM.


Assuntos
Isocumarinas , Penicillium , Fungos/metabolismo , Estrutura Molecular , Penicillium/química , alfa-Glucosidases/metabolismo
11.
Int J Mol Sci ; 23(18)2022 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-36142822

RESUMO

The soybean pod borer (Leguminivora glycinivorella) (SPB) is a major cause of soybean (Glycine max L.) yield losses in northeast Asia, thus it is desirable to elucidate the resistance mechanisms involved in soybean response to the SPB. However, few studies have mapped SPB-resistant quantitative trait loci (QTLs) and deciphered the response mechanism in soybean. Here, we selected two soybean varieties, JY93 (SPB-resistant) and K6 (SPB-sensitive), to construct F2 and F2:3 populations for QTL mapping and collected pod shells before and after SPB larvae chewed on the two parents to perform RNA-Seq, which can identify stable QTLs and explore the response mechanism of soybean to the SPB. The results show that four QTLs underlying SPB damage to seeds were detected on chromosomes 4, 9, 13, and 15. Among them, qESP-9-1 was scanned in all environments, hence it can be considered a stable QTL. All QTLs explained 0.79 to 6.09% of the phenotypic variation. Meanwhile, 2298 and 3509 DEGs were identified for JY93 and K6, respectively, after the SPB attack, and most of these genes were upregulated. Gene Ontology enrichment results indicated that the SPB-induced and differently expressed genes in both parents are involved in biological processes such as wound response, signal transduction, immune response, and phytohormone pathways. Interestingly, secondary metabolic processes such as flavonoid synthesis were only significantly enriched in the upregulated genes of JY93 after SPB chewing compared with K6. Finally, we identified 18 candidate genes related to soybean pod borer resistance through the integration of QTL mapping and RNA-Seq analysis. Seven of these genes had similar expression patterns to the mapping parents in four additional soybean germplasm after feeding by the SPB. These results provide additional knowledge of the early response and induced defense mechanisms against the SPB in soybean, which could help in breeding SPB-resistant soybean accessions.


Assuntos
Mariposas , Locos de Características Quantitativas , Animais , Mapeamento Cromossômico/métodos , Flavonoides/metabolismo , Mariposas/genética , Fenótipo , Melhoramento Vegetal , Reguladores de Crescimento de Plantas/metabolismo , RNA-Seq , Sementes/genética , Glycine max/genética , Glycine max/metabolismo
12.
Immun Ageing ; 18(1): 21, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33947427

RESUMO

BACKGROUND: Chronic infections played a detrimental role on health outcomes in the aged population, and had complex associations with lymphocyte subsets distribution. Our study aimed to explore the predictive roles of chronic infections, lymphopenia, and lymphocyte subsets on unexpected admission and mortality in the institutionalized oldest-old during 3 year follow-up period. RESULTS: There were 163 participants enrolled prospectively with median age of 87.3 years (IQR: 83.1-90.2), male of 88.3%, and being followed for 156.4 weeks (IQR: 136.9-156.4 weeks). The unexpected admission and mortality rates were 55.2 and 24.5% respectively. The Cox proportional hazards models demonstrated the 3rd quartile of cytomegalovirus IgG (OR: 3.26, 95% CI: 1.55-6.84), lymphopenia (OR: 2.85, 95% CI: 1.2-6.74), and 1st quartile of CD19+ B cell count (OR: 2.84, 95% CI: 1.29-6.25) predicted elevated risks of unexpected admission after adjusting for potential confounders; while the 3rd quartile of CD3+ T cell indicated a reduced risk of mortality (OR: 0.19, 95% CI: 0.05-0.71). Negative association between CMV IgG and CD19+ B cell count suggested that CMV infection might lead to B cell depletion via decreasing memory B cells repertoire. CONCLUSIONS: CMV infection, lymphopenia, and CD19+ B cell depletion might predict greater risk of unexpected admission, while more CD3+ T cell would suggest a reduced risk of mortality among the oldest-old population. A non-linear or U-shaped relationship was supposed between health outcomes and CMV infection, CD3+ T cell, or CD19+ B cell counts. Further prospective studies with more participants included would be needed to elucidate above findings.

13.
BMC Geriatr ; 21(1): 726, 2021 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-34922488

RESUMO

BACKGROUND: Few studies have made longitudinal comparisons between frailty phenotype (FP) and frailty index (FI) changes. We aimed to investigate frailty status changes defined by FP and FI concurrently, and to compare the associated factors and incident disability among different combination of FI and FP trajectory groups. METHODS: Data on respondents aged over 50 who completed the 1999, 2003 and 2007 Taiwan Longitudinal Study on Aging (TLSA) surveys (n = 2807) were excerpted. Changes of FI, FP and major time-dependent variables were constructed by group-based trajectory modeling. Logistic regression was used to investigate the associated factors and relationships with incident disability among different frailty trajectories. RESULTS: We identified four FP trajectories - stably robust, worsened frailty, improved frailty, and stably frail and three FI trajectories - stable FI, moderate increase FI and rapid increase FI. Lower self-rated health, mobility impairment, and depressed mood were associated with unfavorable FP and FI changes (all p < 0.001). Regardless of FP trajectory groups, the moderate and rapid increase FI group had significantly more comorbidities than the stable FI group, and more visual, hearing, oral intake impairment, more difficulty in meeting living expenses, and poorer cognitive function in ≥65-year-olds (all p < 0.05). In addition, the worsened frailty, improved frailty, and stably frail groups had ORs for incident disability of 10.5, 3.0, and 13.4, respectively, compared with the stably robust group (all p < 0.01); the moderate and rapid increase FI groups had 8.4-fold and 77.5-fold higher risk than the stable FI group (both p < 0.001). When combining FI and FP trajectories, risk increased with FI trajectory steepness, independent of FP change (all p < 0.01 in rapid increase FI vs stable FI). CONCLUSIONS: Four FP trajectories (stably robust, worsened frailty, improved frailty, and stably frail) and three FI trajectories (stable FI, moderate increase FI and rapid increase FI) were identified. Lower self-rated health, mobility impairment, and depressed mood were associated with both unfavorable FP and FI trajectories. Nevertheless, even for individuals in stably robust or improved frailty FP groups, moderate or rapid increase in FI, either due to comorbidities, sensory impairment, cognitive deficits, or financial challenges, may still increase the risk of incident disability.


Assuntos
Fragilidade , Idoso , Envelhecimento , Idoso Fragilizado , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Avaliação Geriátrica , Humanos , Estudos Longitudinais
14.
Int J Mol Sci ; 22(3)2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33572787

RESUMO

Age-related macular degeneration (AMD) is the progressive degeneration of the retinal pigment epithelium (RPE), retina, and choriocapillaris among elderly individuals and is the leading cause of blindness worldwide. Thus, a better understanding of the underlying mechanisms in retinal tissue activated by blue light exposure is important for developing novel treatment and intervention strategies. In this study, blue-light-emitting diodes with a wavelength of 440 nm were applied to RPE cells at a dose of 3.7 ± 0.75 mW/cm2 for 24 h. ARPE-19 cells were used to investigate the underlying mechanism induced by blue light exposure. A trypan blue exclusion assay was used for the cell viability determination. Flow cytometry was used for apoptosis rate detection and autophagy analysis. An immunofluorescence microscopy analysis was used to investigate cellular oxidative stress and DNA damage using DCFDA fluorescence staining and an anti-γH2AX antibody. Blue light exposure of zebrafish larvae was established to investigate the effect on retinal tissue development in vivo. To further demonstrate the comprehensive effect of blue light on ARPE-19 cells, next-generation sequencing (NGS) was performed for an ingenuity pathway analysis (IPA) to reveal additional related mechanisms. The results showed that blue light exposure caused a decrease in cell proliferation and an increase in apoptosis in ARPE-19 cells in a time-dependent manner. Oxidative stress increased during the early stage of 2 h of exposure and activated DNA damage in ARPE-19 cells after 8 h. Furthermore, autophagy was activated in response to blue light exposure at 24-48 h. The zebrafish larvae model showed the unfavorable effect of blue light in prohibiting retinal tissue development. The RNA-Seq results confirmed that blue light induced cell death and participated in tissue growth inhibition and maturation. The current study reveals the mechanisms by which blue light induces cell death in a time-dependent manner. Moreover, both the in vivo and NGS data uncovered blue light's effect on retinal tissue development, suggesting that exposing children to blue light could be relatively dangerous. These results could benefit the development of preventive strategies utilizing herbal medicine-based treatments for eye diseases or degeneration in the future.


Assuntos
Autofagia/efeitos da radiação , Dano ao DNA/efeitos da radiação , Luz/efeitos adversos , Degeneração Macular/etiologia , Estresse Oxidativo/efeitos da radiação , Epitélio Pigmentado da Retina/efeitos da radiação , Animais , Linhagem Celular , Modelos Animais de Doenças , Humanos , Degeneração Macular/genética , Degeneração Macular/metabolismo , Degeneração Macular/patologia , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/patologia , Peixe-Zebra
15.
Molecules ; 25(17)2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32887242

RESUMO

The effects of microbial transglutaminase (MTGase) cross-linking on the physicochemical characteristics of individual caseins were investigated. MTGase was used to modify three major individual caseins, namely, κ-casein (κ-CN), αS-casein (αS-CN) and ß-casein (ß-CN). The SDS-PAGE analysis revealed that MTGase-induced cross-linking occurred during the reaction and that some components with high molecular weights (>130 kDa) were formed from the individual proteins κ-CN, αS-CN and ß-CN. Scanning electron microscopy (SEM) and particle size analysis respectively demonstrated that the κ-CN, αS-CN and ß-CN particle diameters and protein microstructures were larger and polymerized after MTGase cross-linking. The polymerized κ-CN (~749.9 nm) was smaller than that of ß-CN (~7909.3 nm) and αS-CN (~7909.3 nm). The enzyme kinetics results showed KM values of 3.04 × 10-6, 2.37 × 10-4 and 8.90 × 10-3 M for κ-CN, αS-CN and ß-CN, respectively, and, furthermore, kcat values of 5.17 × 10-4, 1.92 × 10-3 and 4.76 × 10-2 1/s, for κ-CN, αS-CN and ß-CN, respectively. Our results revealed that the cross-linking of ß-CN catalyzed by MTGase was faster than that of αS-CN or κ-CN. Overall, the polymers that formed in the individual caseins in the presence of MTGase presented a higher molecular weight and larger particles.


Assuntos
Bactérias/enzimologia , Caseínas/química , Fenômenos Químicos , Reagentes de Ligações Cruzadas/química , Transglutaminases/metabolismo , Caseínas/ultraestrutura , Cinética , Tamanho da Partícula , Polimerização
16.
J Biol Chem ; 293(31): 12259-12270, 2018 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-29929979

RESUMO

Certain dysregulated chondrocyte metabolic adaptive responses such as decreased activity of the master regulator of energy metabolism AMP-activated protein kinase (AMPK) promote osteoarthritis (OA). Metabolism intersects with epigenetic and transcriptional responses. Hence, we studied chondrocyte ATP-citrate lyase (ACLY), which generates acetyl-CoA from mitochondrial-derived citrate, and modulates acetylation of histones and transcription factors. We assessed ACLY in normal and OA human knee chondrocytes and cartilages by Western blotting and immunohistochemistry, and quantified acetyl-CoA fluorometrically. We examined histone and transcription factor lysine acetylation by Western blotting, and assessed histone H3K9 and H3K27 occupancy of iNOS, MMP3, and MMP13 promoters by chromatin immunoprecipitation (ChIP) and quantitative PCR (qPCR). We analyzed iNOS, MMP3, MMP13, aggrecan (ACAN), and Col2a1 gene expression by RT-qPCR. Glucose availability regulated ACLY expression and function, nucleocytosolic acetyl-CoA, and histone acetylation. Human knee OA chondrocytes exhibited increased ACLY activation (assessed by Ser-455 phosphorylation), associated with increased H3K9 and H3K27 acetylation. Inhibition of ACLY attenuated IL-1ß-induced transcription of iNOS, MMP3, and MMP13 by suppressing acetylation of p65 NF-κB, H3K9, and H3K27, blunted release of NO, MMP3, and MMP13, and also reduced SOX9 acetylation that promoted SOX9 nuclear translocation, leading to increased aggrecan and Col2a1 mRNA expression. ACLY is a novel player involved in regulation of cartilage matrix metabolism. Increased ACLY activity in OA chondrocytes increased nucleocytosolic acetyl-CoA, leading to increased matrix catabolism via dysregulated histone and transcription factor acetylation. Pharmacologic ACLY inhibition in OA chondrocytes globally reverses these changes and stimulates matrix gene expression and AMPK activation, supporting translational investigation in OA.


Assuntos
ATP Citrato (pro-S)-Liase/metabolismo , Cartilagem Articular/enzimologia , Condrócitos/enzimologia , Matriz Extracelular/enzimologia , Osteoartrite do Joelho/enzimologia , ATP Citrato (pro-S)-Liase/genética , Acetilcoenzima A/metabolismo , Acetilação , Agrecanas/genética , Agrecanas/metabolismo , Cartilagem Articular/metabolismo , Células Cultivadas , Condrócitos/metabolismo , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Histonas/metabolismo , Humanos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/genética , Metaloproteinase 3 da Matriz/metabolismo , Osteoartrite do Joelho/genética , Osteoartrite do Joelho/metabolismo
17.
J Am Chem Soc ; 141(7): 3153-3159, 2019 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-30678456

RESUMO

Carbon-carbon bond-forming reductive elimination from elusive organocopper(III) complexes has been considered the key step in many copper-catalyzed and organocuprate reactions. However, organocopper(III) complexes with well-defined structures that can undergo reductive elimination are extremely rare, especially for the formation of Csp3-Csp3 bonds. We report herein a general method for the synthesis of a series of [alkyl-CuIII-(CF3)3]- complexes, the structures of which have been unequivocally characterized by NMR spectroscopy, mass spectrometry, and X-ray crystal diffraction. At elevated temperature, these complexes undergo reductive elimination following first-order kinetics, forming alkyl-CF3 products with good yields (up to 91%). Both kinetic studies and DFT calculations indicate that the reductive elimination to form Csp3-CF3 bonds proceeds through a concerted transition state, with a Δ H⧧ = 20 kcal/mol barrier.

18.
FASEB J ; 32(7): 3870-3877, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29475396

RESUMO

Appropriate sexual selection or individual sexual attractiveness is closely associated with the reproductive success of a species. Here, we report that young male flies exhibit innate courtship preference for female flies that are raised on higher-yeast diets and that have greater body weight and fecundity, but reduced locomotor activity and shortened lifespan. Male flies discriminate among females that have been fed diets that contain 3 different yeast concentrations-1, 5, and 20% yeast- via gustatory, but not visual or olfactory, perception. Female flies that are raised on higher-yeast diets exhibit elevated expression levels of Drosophila insulin-like peptides (di lps), and we demonstrate that hypomorphic mutations of di lp2, 3, 5 or foxo, as well as oenocyte-specific gene disruption of the insulin receptor, all abolish this male courtship preference for high yeast-fed females. Moreover, our data demonstrate that disrupted di lp signaling can alter the expression profile of some cuticular hydrocarbons (CHCs) in female flies, and that genetic inhibition of an enzyme involved in the biosynthesis of CHCs in oenocytes, elongase F, also eliminates the male courtship preference. Together, our findings provide mechanistic insights that link female reproductive potential to sexual attractiveness, thereby encouraging adaptive mating and optimal reproductive success.-Lin, W.-S., Yeh, S.-R., Fan, S.-Z., Chen, L.-Y., Yen, J.-H., Fu, T.-F., Wu, M.-S., Wang, P.-Y. Insulin signaling in female Drosophila links diet and sexual attractiveness.


Assuntos
Dieta , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Preferência de Acasalamento Animal , Animais , Proteínas de Drosophila/genética , Drosophila melanogaster/fisiologia , Feminino , Peptídeos e Proteínas de Sinalização Intercelular/genética , Masculino , Transdução de Sinais
20.
Phys Chem Chem Phys ; 21(32): 17605-17612, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31384855

RESUMO

The conversion of N2(g) to NH3(g) is an important industrial process that plays a vital role in sustaining the current human population. This chemical transformation relies heavily on the Haber-Bosch process (N2 thermal reduction, N2TR), which requires enormous quantities of energy (2% of the world supply) and extreme conditions (200 atm and 500 °C). Alternatively, N2(g) can be reduced to NH3(g) through electrochemical means (N2ER), which may be a less energy intensive and lower-capital approach since the H atoms come from H2O not H2. However, N2ER efficiency is far from satisfactory. In order to provide the basis for developing a new generation of energy efficient processes, we report the detailed atomistic mechanism and kinetics for N2ER on Ru(0001) along with a comparison to N2TR. We obtained these results using a new electrochemical model for quantum mechanics (QM) calculations to obtain free energy surfaces for all plausible reaction pathways for N2ER under a constant electrode potential of 0.0 VSHE. For both processes, the elementary steps involve several steps of breaking of the NN bonds, hydrogenation of surface N2HX or NHX, and NH3 release. We find similar energetics for the NN cleavage steps for both systems. However, the hydrogenation steps are very different, leading to much lower free energy barriers for N2ER compared to N2TR. Thus, N2ER favors an associative route where successive hydrogen atoms are added to N2 prior to breaking the NN bonds rather than the dissociative route preferred by N2TR, where the NN bonds are broken first followed by the addition of Hs. Our QM results provide the detailed free energy surfaces for N2ER and N2TR, suggesting a strategy for improving the efficiency of N2ER.

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