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1.
Stem Cells ; 41(4): 328-340, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-36640125

RESUMO

Given the increasing popularity of electronic cigarettes (e-cigs), it is imperative to evaluate the potential health risks of e-cigs, especially in users with preexisting health concerns such as pulmonary arterial hypertension (PAH). The aim of the present study was to investigate whether differential susceptibility exists between healthy and patients with PAH to e-cig exposure and the molecular mechanisms contributing to it. Patient-specific induced pluripotent stem cell-derived endothelial cells (iPSC-ECs) from healthy individuals and patients with PAH were used to investigate whether e-cig contributes to the pathophysiology of PAH and affects EC homeostasis in PAH. Our results showed that PAH iPSC-ECs showed a greater amount of damage than healthy iPSC-ECs upon e-cig exposure. Transcriptomic analyses revealed that differential expression of Akt3 may be responsible for increased autophagic flux impairment in PAH iPSC-ECs, which underlies increased susceptibility upon e-cig exposure. Moreover, knockdown of Akt3 in healthy iPSC-ECs significantly induced autophagic flux impairment and endothelial dysfunction, which further increased with e-cig treatment, thus mimicking the PAH cell phenotype after e-cig exposure. In addition, functional disruption of mTORC2 by knocking down Rictor in PAH iPSC-ECs caused autophagic flux impairment, which was mediated by downregulation of Akt3. Finally, pharmacological induction of autophagy via direct inhibition of mTORC1 and indirect activation of mTORC2 with rapamycin reverses e-cig-induced decreased Akt3 expression, endothelial dysfunction, autophagic flux impairment, and decreased cell viability, and migration in PAH iPSC-ECs. Taken together, these data suggest a potential link between autophagy and Akt3-mediated increased susceptibility to e-cig in PAH.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Células-Tronco Pluripotentes Induzidas , Hipertensão Arterial Pulmonar , Humanos , Hipertensão Arterial Pulmonar/metabolismo , Células Endoteliais/metabolismo , Autofagia , Células-Tronco Pluripotentes Induzidas/fisiologia
2.
Int J Mol Sci ; 24(8)2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37108160

RESUMO

Tumor necrosis factor superfamily 14 (TNFSF14) is also known as the LT-related inducible ligand (LIGHT). It can bind to the herpesvirus invasion mediator and lymphotoxin-ß receptor to perform its biological activity. LIGHT has multiple physiological functions, including strengthening the synthesis of nitric oxide, reactive oxygen species, and cytokines. LIGHT also stimulates angiogenesis in tumors and induces the synthesis of high endothelial venules; degrades the extracellular matrix in thoracic aortic dissection, and induces the expression of interleukin-8, cyclooxygenase-2, and cell adhesion molecules in endothelial cells. While LIGHT induces tissue inflammation, its effects on angiogenesis after tissue ischemia are unclear. Thus, we analyzed these effects in the current study. In this study, the animal model of hind limb ischemia surgery in C57BL/6 mice was performed. Doppler ultrasound, immunohistochemical staining, and Western blotting were employed to analyze the situation of angiogenesis. In addition, human endothelial progenitor cells (EPCs) were used for in vitro studies to analyze the possible mechanisms. The results in the animal study showed that LIGHT injection inhibited angiogenesis in ischemic limbs. For the in vitro studies, LIGHT inhibited the expression of integrins and E-selectin; decreased migration and tube formation capabilities, mitochondrial respiration, and succinate dehydrogenase activity; and promoted senescence in EPCs. Western blotting revealed that the impairment of EPC function by LIGHT may be due to its effects on the proper functioning of the intracellular Akt signaling pathway, endothelial nitrite oxide synthase (eNOS), and mitochondrial respiration. In conclusion, LIGHT inhibits angiogenesis after tissue ischemia. This may be related to the clamped EPC function.


Assuntos
Células Progenitoras Endoteliais , Membro 14 da Superfamília de Ligantes de Fatores de Necrose Tumoral , Animais , Humanos , Camundongos , Movimento Celular , Células Progenitoras Endoteliais/metabolismo , Isquemia/metabolismo , Camundongos Endogâmicos C57BL , Neovascularização Patológica/patologia , Neovascularização Fisiológica , Óxido Nítrico Sintase Tipo III/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Membro 14 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo
3.
Behav Res Methods ; 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37985636

RESUMO

A testlet-based visual analogue scale (VAS) is a doubly bounded scaling approach (e.g., from 0% to 100% or from 0 to 1) composed of multiple adjectives, nouns, or sentences (statements/items) within testlets for measuring individuals' attitudes, opinions, or career interests. While testlet-based VASs have many advantages over Likert scales, such as reducing response style effects, the development of proper statistical models for analyzing testlet-based VAS data lags behind. This paper proposes a novel beta copula model and a competing logit-normal model based on the item response theory framework, assessed by Bayesian parameter estimation, model comparison, and goodness-of-fit statistics. An empirical career interest dataset based on a testlet-based VAS design was analyzed using the proposed models. Simulation studies were conducted to assess the two models' parameter recovery. The results show that the beta copula model had superior fit in the empirical data analysis, and also exhibited good parameter recovery in the simulation studies, suggesting that it is a promising statistical approach to testlet-based doubly bounded responses.

4.
Part Fibre Toxicol ; 17(1): 41, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32799885

RESUMO

BACKGROUND: Particulate matters (PMs) in ambient air pollution are closely related to the incidence of respiratory diseases and decreased lung function. Our previous report demonstrated that PMs-induced oxidative stress increased the expression of proinflammatory intracellular adhesion molecule-1 (ICAM-1) through the IL-6/AKT/STAT3/NF-κB pathway in A549 cells. However, the role of O-PMs in epithelial-mesenchymal transition (EMT) development and pulmonary fibrosis and the related mechanisms have not been determined. The aim of this study was to investigate the effects of O-PMs on the pathogenesis of EMT and pulmonary fibrosis as well as the expression of ETS-1 and NF-κB p65, in vitro and in vivo. RESULTS: O-PMs treatment induced EMT development, fibronectin expression, and cell migration. O-PMs affected the expression of the EMT-related transcription factors NF-κB p65 and ETS-1. Interference with NF-κB p65 significantly decreased O-PMs-induced fibronectin expression. In addition, O-PMs affected the expression of fibronectin, E-cadherin, and vimentin through modulating ETS-1 expression. ATN-161, an antagonist of integrin α5ß1, decreased the expression of fibronectin and ETS-1 and EMT development. EMT development and the expression of fibronectin and ETS-1 were increased in the lung tissue of mice after exposure to PMs for 7 and 14 days. There was a significant correlation between fibronectin and ETS-1 expression in human pulmonary fibrosis tissue. CONCLUSION: O-PMs can induce EMT and fibronectin expression through the activation of transcription factors ETS-1 and NF-κB in A549 cells. PMs can induce EMT development and the expression of fibronectin and ETS-1 in mouse lung tissues. These findings suggest that the ETS-1 pathway could be a novel and alternative mechanism for EMT development and pulmonary fibrosis.


Assuntos
Poluentes Atmosféricos/toxicidade , Pulmão/fisiopatologia , Material Particulado/toxicidade , Células A549 , Células Epiteliais Alveolares , Animais , Transição Epitelial-Mesenquimal , Fibronectinas/metabolismo , Humanos , Camundongos , NF-kappa B/metabolismo , Fibrose Pulmonar , Fator de Transcrição RelA
5.
Part Fibre Toxicol ; 15(1): 4, 2018 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-29329563

RESUMO

BACKGROUND: Epidemiological studies have shown that ambient air pollution is closely associated with increased respiratory inflammation and decreased lung function. Particulate matters (PMs) are major components of air pollution that damages lung cells. However, the mechanisms remain to be elucidated. This study examines the effects of PMs on intercellular adhesion molecule-1 (ICAM-1) expression and the related mechanisms in vitro and in vivo. RESULT: The cytotoxicity, reactive oxygen species (ROS) generation, and monocyte adherence to A549 cells were more severely affected by treatment with O-PMs (organic solvent-extractable fraction of SRM1649b) than with W-PMs (water-soluble fraction of SRM1649b). We observed a significant increase in ICAM-1 expression by O-PMs, but not W-PMs. O-PMs also induced the phosphorylation of AKT, p65, and STAT3. Pretreating A549 cells with N-acetyl cysteine (NAC), an antioxidant, attenuated O-PMs-induced ROS generation, the phosphorylation of the mentioned kinases, and the expression of ICAM-1. Furthermore, an AKT inhibitor (LY294002), NF-κB inhibitor (BAY11-7082), and STAT3 inhibitor (Stattic) significantly down-regulated O-PMs-induced ICAM-1 expression as well as the adhesion of U937 cells to epithelial cells. Interleukin-6 (IL-6) was the most significantly changed cytokine in O-PMs-treated A549 cells according to the analysis of the cytokine antibody array. The IL-6 receptor inhibitor tocilizumab (TCZ) and small interfering RNA for IL-6 significantly reduced ICAM-1 secretion and expression as well as the reduction of the AKT, p65, and STAT3 phosphorylation in O-PMs-treated A549 cells. In addition, the intratracheal instillation of PMs significantly increased the levels of the ICAM-1 and IL-6 in lung tissues and plasma in WT mice, but not in IL-6 knockout mice. Pre-administration of NAC attenuated those PMs-induced adverse effects in WT mice. Furthermore, patients with chronic obstructive pulmonary disease (COPD) had higher plasma levels of ICAM-1 and IL-6 compared to healthy subjects. CONCLUSION: These results suggest that PMs increase ICAM-1 expression in pulmonary epithelial cells in vitro and in vivo through the IL-6/AKT/STAT3/NF-κB signaling pathway.


Assuntos
Poluentes Atmosféricos/toxicidade , Molécula 1 de Adesão Intercelular/genética , Pulmão/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Material Particulado/toxicidade , Doença Pulmonar Obstrutiva Crônica/sangue , Transdução de Sinais , Células A549 , Poluentes Atmosféricos/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Humanos , Exposição por Inalação , Molécula 1 de Adesão Intercelular/sangue , Interleucina-6/sangue , Interleucina-6/metabolismo , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Estresse Oxidativo/genética , Material Particulado/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição STAT3/metabolismo , Solubilidade
6.
Int Wound J ; 15(4): 605-617, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29659146

RESUMO

Curcumin, a constituent of the turmeric plant, has antitumor, anti-inflammatory, and antioxidative effects, but its effects on wound healing are unclear. We created back wounds in 72 mice and treated them with or without topical curcumin (0.2 mg/mL) in Pluronic F127 gel (20%) daily for 3, 5, 7, 9, and 12 days. Healing in wounds was evaluated from gross appearance, microscopically by haematoxylin and eosin staining, by immunohistochemistry for tumour necrosis factor alpha and alpha smooth muscle actin, and by polymerase chain reaction amplification of mRNA expression levels. Treatment caused fast wound closure with well-formed granulation tissue dominated by collagen deposition and regenerating epithelium. Curcumin increased the levels of tumour necrosis factor alpha mRNA and protein in the early phase of healing, which then decreased significantly. However, these levels remained high in controls. Levels of collagen were significantly higher in curcumin-treated wounds. Immunohistochemical staining for alpha smooth muscle actin was increased in curcumin-treated mice on days 7 and 12. Curcumin treatment significantly suppressed matrix metallopeptidase-9 and stimulated alpha smooth muscle levels in tumour necrosis factor alpha-treated fibroblasts via nuclear factor kappa B signalling. Thus, topical curcumin accelerated wound healing in mice by regulating the levels of various cytokines.


Assuntos
Actinas/uso terapêutico , Colágeno/uso terapêutico , Curcumina/uso terapêutico , Fibroblastos/efeitos dos fármacos , Metaloproteinase 9 da Matriz/uso terapêutico , Fator de Necrose Tumoral alfa/uso terapêutico , Cicatrização/efeitos dos fármacos , Ferimentos e Lesões/tratamento farmacológico , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Cicatrização/fisiologia
7.
Biomed Eng Online ; 16(1): 128, 2017 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-29132359

RESUMO

BACKGROUND: Effect of neurofeedback training (NFT) on enhancement of cognitive function or amelioration of clinical symptoms is inconclusive. The trainability of brain rhythm using a neurofeedback system is uncertainty because various experimental designs are used in previous studies. The current study aimed to develop a portable wireless NFT system for alpha rhythm and to validate effect of the NFT system on memory with a sham-controlled group. METHODS: The proposed system contained an EEG signal analysis device and a smartphone with wireless Bluetooth low-energy technology. Instantaneous 1-s EEG power and contiguous 5-min EEG power throughout the training were developed as feedback information. The training performance and its progression were kept to boost usability of our device. Participants were blinded and randomly assigned into either the control group receiving random 4-Hz power or Alpha group receiving 8-12-Hz power. Working memory and episodic memory were assessed by the backward digital span task and word-pair task, respectively. RESULTS: The portable neurofeedback system had advantages of a tiny size and long-term recording and demonstrated trainability of alpha rhythm in terms of significant increase of power and duration of 8-12 Hz. Moreover, accuracies of the backward digital span task and word-pair task showed significant enhancement in the Alpha group after training compared to the control group. CONCLUSIONS: Our tiny portable device demonstrated success trainability of alpha rhythm and enhanced two kinds of memories. The present study suggest that the portable neurofeedback system provides an alternative intervention for memory enhancement.


Assuntos
Ritmo alfa , Memória/fisiologia , Neurorretroalimentação/instrumentação , Tecnologia sem Fio , Adulto , Cognição/fisiologia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Processamento de Sinais Assistido por Computador
8.
Arch Toxicol ; 91(5): 2165-2178, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27752740

RESUMO

Aryl hydrocarbon receptor (AHR), a ligand-activated transcription factor, has been studied extensively in carcinogenesis through the genomic pathway. In recent years, AHR has also been reported to exert positive or negative effects on epithelial-mesenchymal transition (EMT), the crucial step in tumor malignant progression. However, the detailed mechanism remains controversial. Analysis of AHR-expression levels in non-small cell lung cancer cell lines and lung cancer tissues revealed an inverse correlation between AHR protein levels and tumor cell invasion and metastasis. Overexpression of wild-type AHR in H1299 cells (AHR poorly expressed, potently invasive) not only accelerated mesenchymal vimentin degradation, but also prevented cell invasion in vitro and in vivo. In the absence of AHR agonists, the overexpressed AHR protein was predominantly localized in the cytoplasm, where it interacted with vimentin and functioned as an E3 ubiquitin ligase. A 6-h incubation with the proteasome inhibitor MG-132 fully rescued vimentin from AHR-mediated proteasomal degradation. In AHR-overexpressing H1299 cells, either vimentin degradation or invasive suppression could be reversed when glycogen synthase kinase 3 beta (GSK3ß) was inactivated by CHIR-99021 treatment. In contrast, silencing of AHR in A549 cells (AHR highly expressed, weakly invasive) resulted in the downregulation of epithelial biomarkers (E-cadherin and claudin-1), augmentation of mesenchymal vimentin level, and GSK3ß Ser-9 hyper-phosphorylation, which led to enhanced invasiveness. This work demonstrates that cytoplasmic, resting AHR protein may act as an EMT suppressor via a non-genomic pathway. Depletion of cytoplasmic AHR content represents a potential switch for EMT, thereby leading to the scattering of tumor cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Neoplasias Pulmonares/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Vimentina/metabolismo , Idoso , Animais , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Citoplasma/metabolismo , Transição Epitelial-Mesenquimal , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Complexo de Endopeptidases do Proteassoma/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Arch Toxicol ; 90(11): 2779-2792, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26659566

RESUMO

Uremic toxins are considered a risk factor for cardiovascular disorders in kidney diseases, but it is not known whether, under inflammatory conditions, they affect adhesion molecule expression on endothelial cells, which may play a critical role in acute kidney injury (AKI). In the present study, in cardiovascular surgery-related AKI patients, who are known to have high plasma levels of the uremic toxin indoxyl sulfate (IS), plasma levels of IL-1ß were found to be positively correlated with plasma levels of the adhesion molecule E-selectin. In addition, high E-selectin and IL-1ß expression were seen in the kidney of ischemia/reperfusion mice in vivo. We also examined the effects of IS on E-selectin expression by IL-1ß-treated human umbilical vein endothelial cells (HUVECs) and the underlying mechanism. IS pretreatment of HUVECs significantly increased IL-1ß-induced E-selectin expression, monocyte adhesion, and the phosphorylation of mitogen-activated protein kinases (ERK, p38, and JNK) and transcription factors (NF-κB and AP-1), and phosphorylation was decreased by pretreatment with inhibitors of ERK1/2 (PD98059), p38 MAPK (SB202190), and JNK (SP600125). Furthermore, IS increased IL-1ß-induced reactive oxygen species (ROS) production and this effect was inhibited by pretreatment with N-acetylcysteine (a ROS scavenger) or apocynin (a NADPH oxidase inhibitor). Gel shift assays and ChIP-PCR demonstrated that IS enhanced E-selectin expression in IL-1-treated HUVECs by increasing NF-κB and AP-1 DNA-binding activities. Moreover, IS-enhanced E-selectin expression in IL-1ß-treated HUVECs was inhibited by Bay11-7082, a NF-κB inhibitor. Thus, IS may play an important role in the development of cardiovascular disorders in kidney diseases during inflammation by increasing endothelial expression of E-selectin.


Assuntos
Selectina E/metabolismo , Endotélio Vascular/efeitos dos fármacos , Indicã/toxicidade , Interleucina-1beta/agonistas , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Venenos/toxicidade , Regulação para Cima/efeitos dos fármacos , Injúria Renal Aguda/sangue , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/patologia , Injúria Renal Aguda/fisiopatologia , Idoso , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Selectina E/química , Selectina E/genética , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Indicã/sangue , Interleucina-1beta/metabolismo , Rim/irrigação sanguínea , Rim/metabolismo , Rim/patologia , Rim/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Venenos/sangue , Traumatismo por Reperfusão/sangue , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia , Uremia/etiologia
10.
Am J Emerg Med ; 33(1): 130.e3-4, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25088440

RESUMO

Anaphylactic shock is a serious allergic reaction, setting in rapidly, which may lead to life-threatening circulatory failure and necessitates aggressive support to ensure full recovery. We report the case of a 50-year-old man who developed cardiovascular collapse and cardiac arrest to iodine contrast media, occurring during coronary angiography. He was required temporary mechanical circulatory support with an venoarterial extracorporeal membrane oxygenation system by failure of conventional therapy and intra-aortic balloon pump counterpulsation therapy. He had full recovery of cardiac function and released from the hospital 21 days after admission without a neurologic deficit.


Assuntos
Anafilaxia/induzido quimicamente , Anafilaxia/terapia , Meios de Contraste/efeitos adversos , Angiografia Coronária/efeitos adversos , Oxigenação por Membrana Extracorpórea , Parada Cardíaca/induzido quimicamente , Parada Cardíaca/terapia , Humanos , Masculino , Pessoa de Meia-Idade
11.
Am J Emerg Med ; 33(3): 479.e5-6, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25239694

RESUMO

Coronary artery spasm can lead to sudden cardiac death due to ventricular arrhythmias or heart block. Cardiopulmonary resuscitation guidelines recommend the use of epinephrine during cardiopulmonary arrest. However, in the event of cardiac arrest caused by coronary artery spasm, the use of epinephrine may be harmful. We report 2 cases who had witnessed cardiac arrest due to ventricular fibrillation and complete heart block. Intravenous epinephrine was administered during resuscitation.Their hemodynamics did not improve. Emergent coronary angiography revealed that the entire right and left coronary artery systems diffuse spasm. One patient's coronary artery spasm was successfully reversed immediately with administration of intracoronary boluses of nitroglycerin. The other patient's hemodynamic instability persisted,requiring temporary mechanical circulatory support with an intra aortic balloon pump. His hemodynamics finally improved with administration of intravenous diltiazem and nitroglycerin under the intraaortic balloon pump support. They both were discharged from the hospital without any other complications.


Assuntos
Vasoespasmo Coronário/complicações , Epinefrina/efeitos adversos , Parada Cardíaca/etiologia , Vasoconstritores/efeitos adversos , Fibrilação Ventricular/etiologia , Vasoespasmo Coronário/induzido quimicamente , Parada Cardíaca/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade
12.
Chin J Physiol ; 58(3): 156-64, 2015 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-26014121

RESUMO

Lu-Do-Huang (Pracparatum mungo) is a fermented mung bean [corrected] (Vigna radiata) and has long been used as a traditional and functional food in Traditional Chinese Medicine, especially for treating a variety of liver disorders. The present study aimed to evaluate the apoptotic effects of Lu-Do-Huang ethanol extract (LDHE) on Hep3B cells, a human hepatoma cell line. A variety of cellular assays, flow cytometry and immunoblotting were used. Our results showed that LDHE significantly inhibited Hep3B cells growth. Additionally, the cell cycle assay showed that LDHE prevented Hep3B cell entry into S phase and led to an arrest of Hep3B cells in the G0/G1 phase. LDHE induced Hep3B cells to undergo apoptosis as determined through Hep3B cell morphology changes, increase of apoptotic bodies, apoptotic cells, DNA fragmentations and caspase activity. We further examined the protein expression of TRADD, FADD, and Bax to verify the possible apoptotic pathways. The results indicated that LDHE-induced apoptosis in Hep3B cells might be mediated [corrected] by an extrinsic signaling pathway leading to an induction of apoptosis in Hep3B cells. In conclusion, LDHE induced apoptosis and cell cycle arrest in Hep3B cells. Our data provide the evidences regarding the anti-hepatoma potential of LDHE in Hep3B cells.


Assuntos
Apoptose/efeitos dos fármacos , Fabaceae , Extratos Vegetais/farmacologia , Caspases/fisiologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Fabaceae/química , Humanos , Células Tumorais Cultivadas
13.
Small ; 10(3): 591-8, 2014 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-24106109

RESUMO

A novel pH- and redox- dual-responsive tumor-triggered targeting mesoporous silica nanoparticle (TTTMSN) is designed as a drug carrier. The peptide RGDFFFFC is anchored on the surface of mesoporous silica nanoparticles via disulfide bonds, which are redox-responsive, as a gatekeeper as well as a tumor-targeting ligand. PEGylated technology is employed to protect the anchored peptide ligands. The peptide and monomethoxypolyethylene glycol (MPEG) with benzoic-imine bond, which is pH-sensitive, are then connected via "click" chemistry to obtain TTTMSN. In vitro cell research demonstrates that the targeting property of TTTMSN is switched off in normal tissues with neutral pH condition, and switched on in tumor tissues with acidic pH condition after removing the MPEG segment by hydrolysis of benzoic-imine bond under acidic conditions. After deshielding of the MPEG segment, the drug-loaded nanoparticles are easily taken up by tumor cells due to the exposed peptide targeting ligand, and subsequently the redox signal glutathione in tumor cells induces rapid drug release intracellularly after the cleavage of disulfide bond. This novel intelligent TTTMSN drug delivery system has great potential for cancer therapy.


Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas/química , Neoplasias/patologia , Dióxido de Silício/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Humanos , Concentração de Íons de Hidrogênio , Nanopartículas/ultraestrutura , Neoplasias/tratamento farmacológico , Peptídeos/química , Porosidade , Termogravimetria
14.
Phys Chem Chem Phys ; 16(47): 25840-5, 2014 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-25352132

RESUMO

Two luminescent dinuclear gold(I) species, namely diselenophosphinate [Au2{µ-Se2P((CH2)2Ph)2}2] and dithiophosphinate [Au2{µ-S2P((CH2)2Ph)2}2], exhibiting interesting structural, absorption and emission properties have been studied. In the solid state, both complexes exist in a dinuclear monomeric form, exhibiting no aurophilic interaction, and display similar photophysical properties. It is shown, using DFT computations, that Au-Au chemical bonding appears in the first excited state of these complexes, whereas such bonding does not exist in their ground state; Raman spectroscopy experiments, which bring to light the stretching of this new bond, confirm the theoretical results. Moreover, TDDFT computations permitted us to assign the observed absorption bands of the UV-visible spectra of the two species to LMCT transitions and to describe the emission.


Assuntos
Ouro/química , Compostos Organoáuricos/química , Teoria Quântica , Raios Ultravioleta
15.
Mol Oral Microbiol ; 2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38311876

RESUMO

Orthotopic allograft transplantation (OAT) is a significant approach to addressing organ failure. However, persistent immune responses to the allograft affect chronic rejection, which induces OAT vasculopathy (OATV) and organ failure. Porphyromonas gingivalis can infiltrate remote organs via the bloodstream, thereby intensifying the severity of cardiovascular, respiratory, and neurodegenerative diseases and cancer. GroEL, a virulence factor of P. gingivalis promotes pro-inflammatory cytokine production in host cells, which assumes to play a pivotal role in the pathogenesis of cardiovascular diseases. Although the aggravation of OATV is attributable to numerous factors, the role of GroEL remains ambiguous. Therefore, this study aimed to investigate the impact of GroEL on OATV. Aortic grafts extracted from PVG/Seac rats were transplanted into ACI/NKyo rats and in vitro human endothelial progenitor cell (EPC) and coronary artery endothelial cell (HCAEC) models. The experimental findings revealed that GroEL exacerbates OATV in ACI/NKyo rats by affecting EPC and smooth muscle progenitor cell (SMPC) function and enabling the anomalous accumulation of collagen. In vitro, GroEL spurs endothelial-mesenchymal transition in EPCs, reduces HCAEC tube formation and barrier function by downregulating junction proteins, accelerates HCAEC aging by lowering mitochondrial membrane potential and respiratory function, and impedes HCAEC migration by modulating cytoskeleton-associated molecules. This study suggests that P. gingivalis GroEL could potentially augment OATV by impacting vascular progenitor and endothelial cell functions.

16.
Biomacromolecules ; 14(2): 358-66, 2013 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-23286342

RESUMO

In this paper, a facile strategy to develop graphene-based delivery nanosystems for effective drug loading and sustained drug release was proposed and validated. Specifically, biocompatible naphthalene-terminated PEG (NP) and anticancer drugs (curcumin or doxorubicin (DOX)) were simultaneously integrated onto oxidized graphene (GO), leading to self-assembled, nanosized complexes. It was found that the oxidation degree of GO had a significant impact on the drug-loading efficiency and the structural stability of nanosystems. Interestingly, the nanoassemblies resulted in more effective cellular entry of DOX in comparison with free DOX or DOX-loaded PEG-polyester micelles at equivalent DOX dose, as demonstrated by confocal microscopy studies. Moreover, the nanoassemblies not only exhibited a sustained drug release pattern without an initial burst release, but also significantly improved the stability of formulations which were resistant to drug leaking even in the presence of strong surfactants such as aromatic sodium benzenesulfonate (SBen) and aliphatic sodium dodecylsulfonate (SDS). In addition, the nanoassemblies without DOX loading showed negligible in vitro cytotoxicity, whereas DOX-loaded counterparts led to considerable toxicity against HeLa cells. The DOX-mediated cytotoxicity of the graphene-based formulation was around 20 folds lower than that of free DOX, most likely due to the slow DOX release from complexes. A zebrafish model was established to assess the in vivo safety profile of curcumin-loaded nanosystems. The results showed they were able to excrete from the zebrafish body rapidly and had nearly no influence on the zebrafish upgrowth. Those encouraging results may prompt the advance of graphene-based nanotherapeutics for biomedical applications.


Assuntos
Antineoplásicos/administração & dosagem , Portadores de Fármacos , Grafite , Nanoestruturas , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Curcumina/administração & dosagem , Curcumina/química , Curcumina/farmacologia , Preparações de Ação Retardada , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Grafite/química , Células HeLa , Humanos , Micelas , Neoplasias/tratamento farmacológico , Peixe-Zebra
17.
Appl Psychol Meas ; 47(4): 291-311, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37283593

RESUMO

Student evaluation of teaching (SET) assesses students' experiences in a class to evaluate teachers' performance in class. SET essentially comprises three facets: teaching proficiency, student rating harshness, and item properties. The computerized adaptive testing form of SET with an established item pool has been used in educational environments. However, conventional scoring methods ignore the harshness of students toward teachers and, therefore, are unable to provide a valid assessment. In addition, simultaneously estimating teachers' teaching proficiency and students' harshness remains an unaddressed issue in the context of online SET. In the current study, we develop and compare three novel methods-marginal, iterative once, and hybrid approaches-to improve the precision of parameter estimations. A simulation study is conducted to demonstrate that the hybrid method is a promising technique that can substantially outperform traditional methods.

18.
Biomedicines ; 11(5)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37239085

RESUMO

Cardiac transplant recipients face many complications due to transplant rejection. Scientists must conduct animal experiments to study disease onset mechanisms and develop countermeasures. Therefore, many animal models have been developed for research topics including immunopathology of graft rejection, immunosuppressive therapies, anastomotic techniques, and graft preservation techniques. Small experimental animals include rodents, rabbits, and guinea pigs. They have a high metabolic rate, high reproductive rate, small size for easy handling, and low cost. Additionally, they have genetically modified strains for pathological mechanisms research; however, there is a lacuna, as these research results rarely translate directly to clinical applications. Large animals, including canines, pigs, and non-human primates, have anatomical structures and physiological states that are similar to those of humans; therefore, they are often used to validate the results obtained from small animal studies and directly speculate on the feasibility of applying these results in clinical practice. Before 2023, PubMed Central® at the United States National Institute of Health's National Library of Medicine was used for literature searches on the animal models for heart transplantation focusing on the pathological conditions. Unpublished reports and abstracts from conferences were excluded from this review article. We discussed the applications of small- and large-animal models in heart transplantation-related studies. This review article aimed to provide researchers with a complete understanding of animal models for heart transplantation by focusing on the pathological conditions created by each model.

19.
Bioconjug Chem ; 23(1): 125-34, 2012 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-22148643

RESUMO

Cellular uptake and nuclear localization are two major barriers in gene delivery. In order to evaluate whether additional nuclear localization signals (NLSs) can improve gene transfection efficiency, we introduced different kinds of NLSs to TAT-based gene delivery systems to form three kinds of complexes, including TAT-PV/DNA, TAT/DNA/PV, and TAT/DNA/HMGB1. The DNA binding ability of different vectors was evaluated by agarose gel electrophoresis. The in vitro transfections mediated by different complexes under different conditions were carried out. The cells treated by different complexes were observed by confocal microscopy. The MTT assay showed that all complexes did not exhibit apparent cytotoxicity in both HeLa and Cos7 cell lines even at high N/P ratios. The luciferase reporter gene expression mediated by TAT-PV/DNA complexes exhibited about 200-fold enhancement as compared with TAT/DNA complexes. Confocal study showed that, except TAT/DNA/PV, all other complexes exhibited enhanced nuclear accumulation and cellular uptake in both HeLa and Cos7 cell lines. These results indicated that the introduction of nuclear localization signals could enhance the transfection efficacy of TAT-based peptides, implying that the TAT peptide-based vectors demonstrated here have promising potential in gene delivery.


Assuntos
Núcleo Celular/metabolismo , Produtos do Gene tat/genética , Sinais de Localização Nuclear/metabolismo , Transdução de Sinais/genética , Transfecção/métodos , Transporte Ativo do Núcleo Celular , Animais , Células COS , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Chlorocebus aethiops , DNA/genética , Produtos do Gene tat/química , Produtos do Gene tat/farmacologia , Proteína HMGB1/genética , Células HeLa , Humanos , Relação Estrutura-Atividade
20.
Appl Psychol Meas ; 46(8): 662-674, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36262522

RESUMO

The expectation-maximization (EM) algorithm is a commonly used technique for the parameter estimation of the diagnostic classification models (DCMs) with a prespecified Q-matrix; however, it requires O(2 K ) calculations in its expectation-step, which significantly slows down the computation when the number of attributes, K, is large. This study proposes an efficient Metropolis-Hastings Robbins-Monro (eMHRM) algorithm, needing only O(K + 1) calculations in the Monte Carlo expectation step. Furthermore, the item parameters and structural parameters are approximated via the Robbins-Monro algorithm, which does not require time-consuming nonlinear optimization procedures. A series of simulation studies were conducted to compare the eMHRM with the EM and a Metropolis-Hastings (MH) algorithm regarding the parameter recovery and execution time. The outcomes presented in this article reveal that the eMHRM is much more computationally efficient than the EM and MH, and it tends to produce better estimates than the EM when K is large, suggesting that the eMHRM is a promising parameter estimation method for high-dimensional DCMs.

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