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1.
Small ; : e2311129, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38319033

RESUMO

Constructing concentration differences between anions and cations at the ends of an ionic conductor is an effective strategy in electricity generation for powering wearable devices. Temperature gradient or salinity gradient is the driving force behind such devices. But their corresponding power generation devices are greatly limited in actual application due to their complex structure and harsh application conditions. In this study, a novel ionic concentration gradient electric generator based on the evaporation difference of the electrolyte is proposed. The device can be constructed without the need for semipermeable membranes, and operation does not need to build a temperature difference. As a demonstration, a PVA-Na ionic hydrogel is prepared as an electrolyte for the device and achieved a thermovoltage of more than 200 mV and an energy density of 77.94 J m-2 at 323 K. Besides, the device exhibits the capability to sustain a continuous voltage output for a duration exceeding 1500 min, as well as enabling charging and discharging cycles for 100 iterations. For practical applications, a module comprising 16 sub-cells is constructed and successfully utilized to directly power a light-emitting diode. Wearable devices and their corresponding cell modules are also developed to recycle body heat.

2.
Wound Repair Regen ; 32(2): 118-122, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38217307

RESUMO

Chronic wounds are a common and costly health issue affecting millions of individuals in the United States, particularly those with underlying conditions such as diabetes, venous insufficiency, and peripheral artery disease. When standard treatments fail, advanced wound care therapies, such as skin substitutes, are often applied. However, the clinical effectiveness, indications, and comparative benefits of these therapies have not been well established. In this study, we report on the usage of both acellular and cellular, single and bilayer, natural and synthetic, dermal, and epidermal skin substitutes in a VA hospital system. We performed a retrospective chart review to understand the ordering and usage patterns of advanced wound therapies for patients with chronic wounds at the VA Northern California Health Care System. We examined types of products being recommended, categories of users recommending the products, indications for orders, and rate of repeated orders. Neuropathic, venous, or pressure ulcers were the main indications for using advanced wound matrices. Only 15.6% of patients for whom the matrices were ordered had supporting laboratory tests. Exactly 34.3% of the ordered matrices were not applied. And the use of wound matrices resulted in increased costs per patient visit of $1018-$3450. Our study sheds light on the usage patterns of these therapies in a VA healthcare facility and highlights the need for more robust evidence-based studies to determine the true benefits, efficacy, and cost-effectiveness of these innovative treatment options.


Assuntos
Pele Artificial , Cicatrização , Humanos , Estados Unidos , Estudos Retrospectivos , United States Department of Veterans Affairs
3.
Fetal Diagn Ther ; 50(6): 491-500, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37393899

RESUMO

Spina bifida is the most common congenital anomaly of the central nervous system and the first non-fatal fetal lesions to be addressed by fetal intervention. While research in spina bifida has been performed in rodent, nonhuman primate, and canine models, sheep have been a model organism for the disease. This review summarizes the history of development of the ovine model of spina bifida, previous applications, and translation into clinical studies. Initially used by Meuli et al. [Nat Med. 1995;1(4):342-7], fetal myelomeningocele defect creation and in utero repair demonstrated motor function preservation. The addition of myelotomy in this model can reproduce hindbrain herniation malformations, which is the leading cause of mortality and morbidity in humans. Since inception, the ovine models have been validated numerous times as the ideal large animal model for fetal repair, with both locomotive scoring and spina bifida defect scoring adding to the rigor of this model. The ovine model has been used to study different methods of myelomeningocele defect repair, the application of various tissue engineering techniques for neuroprotection and bowel and bladder function. The results of these large animal studies have been translated into human clinical trials including Management of Meningocele Study (MOMS) trial that established current standard of care for prenatal repair of spina bifida defects, and the ongoing trials including the Cellular Therapy for In Utero Repair of Myelomeningocele (CuRe) trial using a stem cell patch for repair. The advancement of these life savings and life-altering therapies began in sheep models, and this notable model continues to be used to further the field including current work with stem cell therapy.


Assuntos
Meningocele , Meningomielocele , Disrafismo Espinal , Gravidez , Feminino , Animais , Ovinos , Cães , Humanos , Meningomielocele/cirurgia , Disrafismo Espinal/cirurgia , Feto/patologia , Cuidado Pré-Natal
4.
Int J Mol Sci ; 24(10)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37240315

RESUMO

Non-alcoholic fatty liver disease (NAFLD), characterized by excessive lipid accumulation in hepatocytes, is an increasing global healthcare burden. Sirtuin 2 (SIRT2) functions as a preventive molecule for NAFLD with incompletely clarified regulatory mechanisms. Metabolic changes and gut microbiota imbalance are critical to the pathogenesis of NAFLD. However, their association with SIRT2 in NAFLD progression is still unknown. Here, we report that SIRT2 knockout (KO) mice are susceptible to HFCS (high-fat/high-cholesterol/high-sucrose)-induced obesity and hepatic steatosis accompanied with an aggravated metabolic profile, which indicates SIRT2 deficiency promotes NAFLD-NASH (nonalcoholic steatohepatitis) progression. Under palmitic acid (PA), cholesterol (CHO), and high glucose (Glu) conditions, SIRT2 deficiency promotes lipid deposition and inflammation in cultured cells. Mechanically, SIRT2 deficiency induces serum metabolites alteration including upregulation of L-proline and downregulation of phosphatidylcholines (PC), lysophosphatidylcholine (LPC), and epinephrine. Furthermore, SIRT2 deficiency promotes gut microbiota dysbiosis. The microbiota composition clustered distinctly in SIRT2 KO mice with decreased Bacteroides and Eubacterium, and increased Acetatifactor. In clinical patients, SIRT2 is downregulated in the NALFD patients compared with healthy controls, and is associated with exacerbated progression of normal liver status to NAFLD to NASH in clinical patients. In conclusion, SIRT2 deficiency accelerates HFCS-induced NAFLD-NASH progression by inducing alteration of gut microbiota and changes of metabolites.


Assuntos
Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fígado/metabolismo , Sirtuína 2/genética , Sirtuína 2/metabolismo , Dieta , Lipídeos , Dieta Hiperlipídica/efeitos adversos , Camundongos Endogâmicos C57BL
5.
Mol Med ; 28(1): 43, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35428170

RESUMO

BACKGROUND: Pancreatic cancer (PC) is a malignancy with a poor prognosis and high mortality. Surgical resection is the only "curative" treatment. However, only a minority of patients with PC can obtain surgery. Improving the overall survival (OS) rate of patients with PC is still a major challenge. Molecular biomarkers are a significant approach for diagnostic and predictive use in PCs. Several prediction models have been developed for patients newly diagnosed with PC that is operable or patients with advanced and metastatic PC; however, these models require further validation. Therefore, precise biomarkers are urgently required to increase the efficiency of predicting a disease-free survival (DFS), OS, and sensitivity to immunotherapy in PC patients and to improve the prognosis of PC. METHODS: In the present study, we first evaluated the highly and selectively expressed targets in PC, using the GeoMxTM Digital Spatial Profiler (DSP) and then, we analyzed the roles of these targets in PCs using TCGA database. RESULTS: LAMB3, FN1, KRT17, KRT19, and ANXA1 were defined as the top five upregulated targets in PC compared with paracancer. The TCGA database results confirmed the expression pattern of LAMB3, FN1, KRT17, KRT19, and ANXA1 in PCs. Significantly, LAMB3, FN1, KRT19, and ANXA1 but not KRT17 can be considered as biomarkers for survival analysis, univariate and multivariate Cox proportional hazards model, and risk model analysis. Furthermore, in combination, LAMB3, FN1, KRT19, and ANXA1 predict the DFS and, in combination, LAMB3, KRT19, and ANXA1 predict the OS. Immunotherapy is significant for PCs that are inoperable. The immune checkpoint blockade (ICB) analysis indicated that higher expressions of FN1 or ANXA1 are correlated with lower ICB response. In contrast, there are no significant differences in the ICB response between high and low expression of LAMB3 and KRT19. CONCLUSIONS: In conclusion, LAMB3, FN1, KRT19, and ANXA1 are good predictors of PC prognosis. Furthermore, FN1 and ANXA1 can be predictors of immunotherapy in PCs.


Assuntos
Neoplasias Pancreáticas , Biomarcadores , Biomarcadores Tumorais , Humanos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Prognóstico , Análise de Sobrevida , Neoplasias Pancreáticas
6.
Brief Bioinform ; 21(5): 1798-1805, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978618

RESUMO

Protein lysine acetylation regulation is an important molecular mechanism for regulating cellular processes and plays critical physiological and pathological roles in cancers and diseases. Although massive acetylation sites have been identified through experimental identification and high-throughput proteomics techniques, their enzyme-specific regulation remains largely unknown. Here, we developed the deep learning-based protein lysine acetylation modification prediction (Deep-PLA) software for histone acetyltransferase (HAT)/histone deacetylase (HDAC)-specific acetylation prediction based on deep learning. Experimentally identified substrates and sites of several HATs and HDACs were curated from the literature to generate enzyme-specific data sets. We integrated various protein sequence features with deep neural network and optimized the hyperparameters with particle swarm optimization, which achieved satisfactory performance. Through comparisons based on cross-validations and testing data sets, the model outperformed previous studies. Meanwhile, we found that protein-protein interactions could enrich enzyme-specific acetylation regulatory relations and visualized this information in the Deep-PLA web server. Furthermore, a cross-cancer analysis of acetylation-associated mutations revealed that acetylation regulation was intensively disrupted by mutations in cancers and heavily implicated in the regulation of cancer signaling. These prediction and analysis results might provide helpful information to reveal the regulatory mechanism of protein acetylation in various biological processes to promote the research on prognosis and treatment of cancers. Therefore, the Deep-PLA predictor and protein acetylation interaction networks could provide helpful information for studying the regulation of protein acetylation. The web server of Deep-PLA could be accessed at http://deeppla.cancerbio.info.


Assuntos
Aprendizado Profundo , Histona Desacetilases/metabolismo , Lisina/metabolismo , Neoplasias/metabolismo , Acetilação , Conjuntos de Dados como Assunto , Humanos , Internet , Neoplasias/enzimologia , Neoplasias/patologia
7.
J Clin Lab Anal ; 36(8): e24586, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35791925

RESUMO

BACKGROUND: This study aimed to explore the relationship between the Sirtuin 3 (SIRT3) gene and endothelial cell dysfunction, contributing to the progression of coronary atherosclerosis driven by hyperglycemia. METHODS: We measured serum SIRT3 levels using enzyme-linked immunosorbent assay in 95 patients with type 2 diabetes mellitus (T2DM) who underwent diagnostic coronary angiography. The patients were divided into two groups according to the presence (n = 45) or absence (n = 50) of coronary artery disease (CAD). Human aortic endothelial cells (HAECs) grown in vitro in a medium with various concentrations of glucose (5.5, 11, 16.5, 22, 27.5, 33, and 38.5 mM) for 24 h were assessed for protein expression of SIRT3, peroxisome proliferator-activated receptor alpha (PPAR-α), endothelial nitric oxide (NO) synthase (eNOS), and inducible NO synthase (iNOS) using Western blot analysis. HAECs were subjected to SIRT3 overexpression or inhibition through SIRT3 adenovirus and siRNA transfection. RESULTS: Serum SIRT3 levels were significantly lower in T2DM patients with CAD than in those without CAD (p = 0.048). The in vitro results showed that HG significantly increased SIRT3, PPAR-α, and eNOS protein expression in a concentration-dependent manner. Moreover, iNOS expression was decreased in HAECs in response to HG. Reduced PPAR-α and eNOS levels and increased iNOS levels were observed in SIRT3 silenced HAECs cells. In contrast, SIRT3 overexpression significantly improved PPAR-α and eNOS expression and suppressed iNOS expression. CONCLUSION: SIRT3 was associated with the progression of atherosclerosis in T2DM patients through upregulation of PPAR-α and eNOS and downregulation of iNOS, which are involved in endothelial dysfunction under hyperglycemic conditions.


Assuntos
Doença da Artéria Coronariana , Diabetes Mellitus Tipo 2 , Hiperglicemia , Sirtuína 3 , Doença da Artéria Coronariana/complicações , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Células Endoteliais , Humanos , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Sirtuína 3/genética , Sirtuína 3/metabolismo
8.
Int Heart J ; 63(4): 755-762, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35831147

RESUMO

Ursolic acid (UA) has been reported to possess several biological benefits, such as anti-cancer, anti-inflammation, antibacterial, and neuroprotective functions. This study detects the function and molecular mechanism of UA in H9c2 cells under hypoxia and reoxygenation (H/R) conditions.Under H/R stimulation, the effects of UA on H9c2 cells were examined using ELISA and western blot assays. The Comparative Toxicogenomics Database was employed to analyze the target molecule of UA. Small interfering RNA was used to knock down CXCL2 expression, further exploring the function of CXCL2 in H/R-induced H9c2 cells. The genes related to the nuclear factor-kappa B (NF-κB) pathway were assessed using western blot analysis.Significant effects of UA on H/R-induced H9c2 cell damage were observed, accompanied by reduced inflammation and oxidative stress injury. Additionally, the increased level of CXCL2 in H/R-induced H9c2 cells was reduced after UA stimulation. Moreover, CXCL2 knockdown strengthened the beneficial effect of UA on H/R-induced H9c2 cells. HY-18739, an activator of the NF-κB pathway, can increase CXCL2 expression. Moreover, the increased levels of p-P65 NF-κB and p-IκBα in H/R-induced H9c2 cells were remarkably attenuated by UA treatment.In summary, the results indicated that UA may alleviate the damage of H9c2 cells by targeting the CXCL2/NF-κB pathway under H/R conditions.


Assuntos
NF-kappa B , Triterpenos , Anti-Inflamatórios/farmacologia , Apoptose , Quimiocina CXCL2/metabolismo , Quimiocina CXCL2/farmacologia , Humanos , Hipóxia/metabolismo , Miócitos Cardíacos/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Triterpenos/metabolismo , Triterpenos/farmacologia , Ácido Ursólico
9.
Molecules ; 27(2)2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35056734

RESUMO

Meloxicam (MLX) is a non-steroidal anti-inflammatory drug used to treat rheumatoid arthritis and osteoarthritis. However, its poor water solubility limits the dissolution process and influences absorption. In order to solve this problem and improve its bioavailability, we prepared it in nanocrystals with three different particle sizes to improve solubility and compare the differences between various particle sizes. The nanocrystal particle sizes were studied through dynamic light scattering (DLS) and laser scattering (LS). Transmission electron microscopy (TEM) was used to characterize the morphology of nanocrystals. The sizes of meloxicam-nanocrystals-A (MLX-NCs-A), meloxicam-nanocrystals-B (MLX-NCs-B), and meloxicam-nanocrystals-C (MLX-NCs-C) were 3.262 ± 0.016 µm, 460.2 ± 9.5 nm, and 204.9 ± 2.8 nm, respectively. Molecular simulation was used to explore the distribution and interaction energy of MLX molecules and stabilizer molecules in water. The results of differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD) proved that the crystalline state did not change in the preparation process. Transport studies of the Caco-2 cell model indicated that the cumulative degree of transport would increase as the particle size decreased. Additionally, plasma concentration-time curves showed that the AUC0-∞ of MLX-NCs-C were 3.58- and 2.92-fold greater than those of MLX-NCs-A and MLX-NCs-B, respectively. These results indicate that preparing MLX in nanocrystals can effectively improve the bioavailability, and the particle size of nanocrystals is an important factor in transmission and absorption.


Assuntos
Meloxicam/química , Meloxicam/farmacocinética , Nanopartículas/química , Administração Cutânea , Administração Oral , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacocinética , Células CACO-2 , Varredura Diferencial de Calorimetria , Avaliação Pré-Clínica de Medicamentos , Difusão Dinâmica da Luz , Humanos , Masculino , Meloxicam/administração & dosagem , Microscopia Eletrônica de Transmissão , Modelos Moleculares , Nanopartículas/administração & dosagem , Tamanho da Partícula , Ratos Sprague-Dawley , Difração de Raios X
10.
Molecules ; 27(1)2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-35011436

RESUMO

Chitosan is a natural polysaccharide, mainly derived from the shell of marine organisms. At present, chitosan has been widely used in the field of biomedicine due to its special characteristics of low toxicity, biocompatibility, biodegradation and low immunogenicity. Chitosan nanoparticles can be easily prepared. Chitosan nanoparticles with positive charge can enhance the adhesion of antigens in nasal mucosa and promote its absorption, which is expected to be used for intranasal vaccine delivery. In this study, we prepared chitosan nanoparticles by a gelation method, and modified the chitosan nanoparticles with mannose by hybridization. Bovine serum albumin (BSA) was used as the model antigen for development of an intranasal vaccine. The preparation technology of the chitosan nanoparticle-based intranasal vaccine delivery system was optimized by design of experiment (DoE). The DoE results showed that mannose-modified chitosan nanoparticles (Man-BSA-CS-NPs) had high modification tolerance and the mean particle size and the surface charge with optimized Man-BSA-CS-NPs were 156 nm and +33.5 mV. FTIR and DSC results confirmed the presence of Man in Man-BSA-CS-NPs. The BSA released from Man-BSA-CS-NPs had no irreversible aggregation or degradation. In addition, the analysis of fluorescence spectroscopy of BSA confirmed an appropriate binding constant between CS and BSA in this study, which could improve the stability of BSA. The cell study in vitro demonstrated the low toxicity and biocompatibility of Man-BSA-CS-NPs. Confocal results showed that the Man-modified BSA-FITC-CS-NPs promote the endocytosis and internalization of BSA-FITC in DC2.4 cells. In vivo studies of mice, Man-BSA-CS-NPs intranasally immunized showed a significantly improvement of BSA-specific serum IgG response and the highest level of BSA-specific IgA expression in nasal lavage fluid. Overall, our study provides a promising method to modify BSA-loaded CS-NPs with mannose, which is worthy of further study.


Assuntos
Quitosana/química , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Desenvolvimento de Vacinas , Vacinas/administração & dosagem , Administração Intranasal , Animais , Linhagem Celular , Sobrevivência Celular , Fenômenos Químicos , Feminino , Humanos , Camundongos , Modelos Animais , Nanopartículas/ultraestrutura , Tamanho da Partícula , Análise Espectral , Termodinâmica , Desenvolvimento de Vacinas/métodos
11.
Drug Dev Ind Pharm ; 46(5): 697-705, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32293206

RESUMO

The purpose of this study was to investigate the nasal absorption rate and nasal mucosal toxicity of thermosensitive ketamine in situ gels containing various absorption enhancers. The optimal composition ratio for the gel matrix was determined to be 17.2% Poloxamer 407 and 2% Poloxamer 188, as this combination resulted in solutions with a gelation point within the range found in the nasal cavity. Ketamine gels containing the tested enhancers, namely, ethylenediaminetetraacetic acid disodium salt, hydroxypropyl-ß-cyclodextrin, propylene glycol, or Tween-80, were compared with enhancer-free counterparts to determine the absorption of the drug, in vivo by measuring its plasma levels in rats and in vitro using a Franz diffusion cell. Moreover, the toxicity of each gel type was assessed by microscopic observation of the morphology of rat nasal mucosa as well as by determining the mobility of the mucosal cilia using an established toad model. The results showed that gels containing hydroxypropyl-ß-cyclodextrin could promote the absorption of ketamine without added toxicity compared to enhancer-free gels. Thus, we consider hydroxypropyl-ß-cyclodextrin as the most promising absorption enhancer for the nasal administration of ketamine using in situ gels.


Assuntos
Portadores de Fármacos/toxicidade , Ketamina/toxicidade , Absorção Nasal/efeitos dos fármacos , Mucosa Nasal/efeitos dos fármacos , Poloxâmero/toxicidade , Administração Intranasal/métodos , Analgésicos/síntese química , Analgésicos/metabolismo , Analgésicos/toxicidade , Animais , Anuros , Portadores de Fármacos/síntese química , Portadores de Fármacos/metabolismo , Feminino , Géis , Ketamina/síntese química , Ketamina/metabolismo , Masculino , Absorção Nasal/fisiologia , Mucosa Nasal/metabolismo , Técnicas de Cultura de Órgãos , Poloxâmero/síntese química , Poloxâmero/metabolismo , Ratos , Ratos Sprague-Dawley , Temperatura
12.
Angew Chem Int Ed Engl ; 59(38): 16352-16356, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32537908

RESUMO

Formaldehyde (FA) is endogenously produced in living systems through a variety of biological processes and has been implicated in many pathological conditions. Detection tools for biological FA are therefore of great interest. Reported here are novel activity-based genetically encoded fluorescent and luminescent probes for detecting FA in aqueous solutions and living mammalian cells. A FA-reactive lysine analogue, PrAK, was site-specifically incorporated into the essential lysine sites of enhanced green fluorescent protein (EGFP) and firefly luciferase (fLuc) to afford fluorescent and luminescent FA probes, respectively. FA selectively reacts with PrAK residues on EGFP and fLuc through a 2-aza-Cope rearrangement, resulting in fluorescence and luminescence turn-on responses, respectively, to FA selectively over potentially interfering reactive species in aqueous buffer. Moreover, the genetically encoded probes are capable of visualizing FA at physiologically relevant levels in living mammalian cells by fluorescence and luminescence imaging, demonstrating their potential as new tools to explore FA biology.


Assuntos
Corantes Fluorescentes/química , Formaldeído/análise , Corantes Fluorescentes/síntese química , Células HEK293 , Humanos , Medições Luminescentes , Estrutura Molecular
13.
Bioorg Med Chem ; 24(15): 3312-29, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27085674

RESUMO

Mucosa-associated lymphoid tissue lymphoma translocation protein 1 (Malt1) is a promising therapeutic target for the treatment of activated B cell-like diffuse large B cell lymphoma (ABC-DLBCL). Several research groups have reported on the development of Malt1 inhibitors and activity-based probes for in vitro and in situ monitoring and modulating Malt1 activity. In this paper, we report on two activity-based Malt1 probes (6 and 7) and a focused library of 19 new Malt1 inhibitors. Our peptide-based probe 6 labels Malt1 in an activity-based manner. In contrast, probe 7, derived from the known covalent inhibitor MI-2, labels both wild type and catalytically inactive Cys to Ala mutant Malt1, suggesting that MI-2 inhibits Malt1 by reacting with a nucleophilic residue other than the active site cysteine. Furthermore, two of our inhibitors (9, apparent IC50 3.0µM, and 13, apparent IC50 2.1µM) show good inhibitory activity against Malt1 and outperform MI-2 (apparent IC50 7.8µM) in our competitive activity-based protein profiling assay.


Assuntos
Inibidores de Caspase/síntese química , Inibidores de Caspase/farmacologia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Proteínas de Neoplasias/antagonistas & inibidores , Carbamatos/síntese química , Carbamatos/química , Carbamatos/farmacologia , Inibidores de Caspase/química , Caspases/metabolismo , Linhagem Celular Tumoral , Descoberta de Drogas/métodos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células Jurkat , Linfoma Difuso de Grandes Células B/enzimologia , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa , Proteínas de Neoplasias/metabolismo , Triazóis/síntese química , Triazóis/química , Triazóis/farmacologia
14.
Cell Biochem Funct ; 34(3): 181-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26968727

RESUMO

The calcium channel blocker (CCB), nifedipine, is a more effective treatment for early- than late-stage cardiac hypertrophy. We investigated the effects of early- and late-stage nifedipine administration on calcium homeostasis, CaMKII (Ca(2+) /calmodulin-dependent protein kinase II) activity and apoptosis of cardiomyocytes under hypertrophic stimulation with angiotensin II (AngII). Primary rat cardiomyocytes were divided into five treatment groups: AK, AngII plus the CaMKII inhibitor, KN-93; AN-1 (early-stage), AngII plus nifedipine × 48 h; AN-2 (late-stage), AngII × 48 h, then AngII plus nifedipine × 48 h; C, untreated; and A, AngII × 48 h. The t1/2ß [time required for intracellular Ca(2+) concentration ([Ca(2+) ]i) to decline to one half of the peak value] decreased; however, CaMKII and SERCA2a (sarcoplasmic reticulum Ca(2+) -ATPase 2a) activities increased in the AN-1 group compared with the AK group. In the AN-2 group compared with the AN-1 group, CaMKII activity, t1/2α [time required for [Ca(2+) ]i to increase from the bottom to one half of peak value], t1/2ß, and apoptosis increased. These results indicate that the timing of CCB administration affects the calcium concentration and apoptosis of hypertrophic cardiomyocytes through the CaMKII-SERCA2a signalling pathway, thereby influencing the drug's protective activity against cardiomyocyte hypertrophy.


Assuntos
Angiotensina II/farmacologia , Apoptose/efeitos dos fármacos , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Cardiomegalia/induzido quimicamente , Cardiomegalia/tratamento farmacológico , Miócitos Cardíacos/efeitos dos fármacos , Nifedipino/farmacologia , Animais , Cardiomegalia/metabolismo , Miócitos Cardíacos/metabolismo , Ratos , Ratos Wistar
15.
Anal Methods ; 16(23): 3646-3653, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38738568

RESUMO

Formaldehyde (FA) is endogenously generated via fundamental biological processes in living systems. Aberrant FA homeostasis in subcellular microenvironments is implicated in numerous pathological conditions. Fluorescent probes for detecting FA in specific organelles are thus of great research interest. Herein, we present a modular strategy to construct diverse organelle-targeting FA probes by incorporating selective organelle-targeting moieties into the scaffold of a 1,8-naphthalimide-derived FA fluorescent probe. These probes react with FA through the 2-aza-Cope arrangement and exhibit highly selective fluorescence increases for detecting FA in aqueous solutions. Moreover, these organelle-targeting probes, i.e., FFP551-Nuc, FFP551-ER, FFP551-Mito, and FFP551-Lyso, allow selective localization and imaging of FA in the nucleus, endoplasmic reticulum, mitochondria, and lysosomes of live mammalian cells, respectively. Furthermore, FFP551-Nuc has been successfully employed to monitor changes of endogenous FA levels in the nucleus of live mammalian cells. Overall, these probes should represent new imaging tools for studying the biology and pathology associated with FA in different intracellular compartments.


Assuntos
Corantes Fluorescentes , Formaldeído , Organelas , Corantes Fluorescentes/química , Formaldeído/química , Humanos , Organelas/química , Organelas/metabolismo , Imagem Óptica/métodos , Células HeLa , Microscopia de Fluorescência/métodos , Animais
16.
ACS Appl Mater Interfaces ; 16(23): 29716-29727, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38814480

RESUMO

The emergence of XBB.1.16 has gained rapid global prominence. Previous studies have elucidated that the infection of SARS-CoV-2 induces alterations in the mitochondrial integrity of host cells, subsequently influencing the cellular response to infection. In this study, we compared the differences in infectivity and pathogenicity between XBB.1.16 and the parental Omicron sublineages BA.1 and BA.2 and assessed their impact on host mitochondria. Our findings suggest that, in comparison with BA.1 and BA.2, XBB.1.16 exhibits more efficient spike protein cleavage, more efficient mediating syncytia formation, mild mitochondriopathy, and less pathogenicity. Altogether, our investigations suggest that, based on the mutation of key sites, XBB.1.16 exhibited enhanced infectivity but lower pathogenicity. This will help us to further investigate the biological functions of key mutation sites.


Assuntos
COVID-19 , Mitocôndrias , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Humanos , COVID-19/virologia , Mitocôndrias/metabolismo , Animais , Mutação , Chlorocebus aethiops , Células Vero , Camundongos , Células HEK293
17.
Cancer Lett ; 590: 216869, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38593918

RESUMO

Lysine acetyltransferase 7 (KAT7), a histone acetyltransferase, has recently been identified as an oncoprotein and has been implicated in the development of various malignancies. However, its specific role in head and neck squamous carcinoma (HNSCC) has not been fully elucidated. Our study revealed that high expression of KAT7 in HNSCC patients is associated with poor survival prognosis and silencing KAT7 inhibits the Warburg effect, leading to reduced proliferation, invasion, and metastatic potential of HNSCC. Further investigation uncovered a link between the high expression of KAT7 in HNSCC and tumor-specific glycolytic metabolism. Notably, KAT7 positively regulates Lactate dehydrogenase A (LDHA), a key enzyme in metabolism, to promote lactate production and create a conducive environment for tumor proliferation and metastasis. Additionally, KAT7 enhances LDHA activity and upregulates LDHA protein expression by acetylating the lysine 118 site of LDHA. Treatment with WM3835, a KAT7 inhibitor, effectively suppressed the growth of subcutaneously implanted HNSCC cells in mice. In conclusion, our findings suggest that KAT7 exerts pro-cancer effects in HNSCC by acetylating LDHA and may serve as a potential therapeutic target. Inhibiting KAT7 or LDHA expression holds promise as a therapeutic strategy to suppress the growth and progression of HNSCC.


Assuntos
Proliferação de Células , Neoplasias de Cabeça e Pescoço , Histona Acetiltransferases , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Animais , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Acetilação , Linhagem Celular Tumoral , Histona Acetiltransferases/metabolismo , Histona Acetiltransferases/genética , Camundongos , L-Lactato Desidrogenase/metabolismo , L-Lactato Desidrogenase/genética , Lisina Acetiltransferases/metabolismo , Lisina Acetiltransferases/genética , Regulação Neoplásica da Expressão Gênica , Camundongos Nus , Efeito Warburg em Oncologia , Masculino , Feminino , Movimento Celular , Ensaios Antitumorais Modelo de Xenoenxerto , Invasividade Neoplásica , Isoenzimas/metabolismo , Isoenzimas/genética
18.
Hellenic J Cardiol ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38582140

RESUMO

BACKGROUND: Sacubitril/valsartan (S/V) has been shown to be an effective antihypertensive drug combination. However, its therapeutic effects on blood pressure (BP), hemodynamics, and left ventricular (LV) remodeling in resistant hypertension (RHTN) remain unclear. METHODS: Eighty-six patients completed this self-control study, during which olmesartan was administered within the first 8 weeks (phase 1), followed by S/V within the second 8 weeks (phase 2), with nifedipine and hydrochlorothiazide taken as background medications. Office BP, echocardiography, and hemodynamics assessment using impedance cardiography were performed at baseline and at the eighth and sixteenth weeks. RESULTS: The reduction in office BP was larger in phase 2 than in phase 1 (19.59/11.66 mmHg vs. 2.88/1.15 mmHg). Furthermore, the treatment in phase 2 provided greater reductions in systemic vascular resistance index (SVRI) and thoracic blood saturation ratio (TBR), with differences between the two phases of -226.59 (-1212.80 to 509.55) dyn·s/cm5/m2 and -0.02 (-0.04 to 0.02). Switching from olmesartan to S/V also significantly reduced E/E', LV mass index, LV end-diastolic volume index, and LV end-systolic volume index (all P < 0.05). Decreases in arterial stiffness, SVRI, and TBR were correlated with changes in indicators of LV remodeling (all P < 0.05). This correlation persisted even after adjusting for confounders including changes in BP. CONCLUSIONS: Switching from olmesartan to S/V effectively lowered BP and reversed ventricular remodeling in RHTN. In addition, hemodynamic improvement was also observed. Changes in hemodynamics played an important role in reversing LV remodeling of S/V, and were independent of its antihypertensive effect.

19.
Int J Mol Sci ; 14(9): 18682-710, 2013 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-24030719

RESUMO

Magnetic particle imaging (MPI) is a promising medical imaging technique producing quantitative images of the distribution of tracer materials (superparamagnetic nanoparticles) without interference from the anatomical background of the imaging objects (either phantoms or lab animals). Theoretically, the MPI platform can image with relatively high temporal and spatial resolution and sensitivity. In practice, the quality of the MPI images hinges on both the applied magnetic field and the properties of the tracer nanoparticles. Langevin theory can model the performance of superparamagnetic nanoparticles and predict the crucial influence of nanoparticle core size on the MPI signal. In addition, the core size distribution, anisotropy of the magnetic core and surface modification of the superparamagnetic nanoparticles also determine the spatial resolution and sensitivity of the MPI images. As a result, through rational design of superparamagnetic nanoparticles, the performance of MPI could be effectively optimized. In this review, the performance of superparamagnetic nanoparticles in MPI is investigated. Rational synthesis and modification of superparamagnetic nanoparticles are discussed and summarized. The potential medical application areas for MPI, including cardiovascular system, oncology, stem cell tracking and immune related imaging are also analyzed and forecasted.


Assuntos
Diagnóstico por Imagem/métodos , Magnetismo , Nanopartículas/química
20.
Materials (Basel) ; 16(17)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37687677

RESUMO

The Si atom diffusion behavior in Ni-based superalloys was evaluated based on first-principles calculations. Also, the site occupation of Si atoms as the melting point depressant elements in Cr, Mo, and W atom doped γ-Ni and γ'-Ni3Fe supercells was discussed and Si atom diffusion behaviors between both adjacent octahedral interstices were analyzed. Calculation results indicated that formation enthalpy (∆Hf) was decreased, stability was improved by doping alloying elements Cr, Mo, and W in γ-Ni and γ'-Ni3Fe supercells, Si atoms were more inclined to occupy octahedral interstices and the diffusion energy barrier was increased by increasing the radius of the doped alloy element. Especially, two diffusion paths were available for Si atoms in the γ'-Ni3Fe and Si diffusion energy barrier around the shared Fe atoms between adjacent octahedral interstices and was significantly lower than that around the shared Ni atoms. The increase of interaction strength between the doped M atom/octahedron constituent atom and Si atom increased Si atom diffusion and decreased the diffusion energy barrier. The Si atom diffusion behavior provides a theoretical basis for the phase structure evolution in wide-gap brazed joints.

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