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1.
J Biomed Sci ; 31(1): 42, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38650023

RESUMO

BACKGROUND: Myocarditis substantially increases the risk of ventricular arrhythmia. Approximately 30% of all ventricular arrhythmia cases in patients with myocarditis originate from the right ventricular outflow tract (RVOT). However, the role of NLRP3 signaling in RVOT arrhythmogenesis remains unclear. METHODS: Rats with myosin peptide-induced myocarditis (experimental group) were treated with an NLRP3 inhibitor (MCC950; 10 mg/kg, daily for 14 days) or left untreated. Then, they were subjected to electrocardiography and echocardiography. Ventricular tissue samples were collected from each rat's RVOT, right ventricular apex (RVA), and left ventricle (LV) and examined through conventional microelectrode and histopathologic analyses. In addition, whole-cell patch-clamp recording, confocal fluorescence microscopy, and Western blotting were performed to evaluate ionic currents, intracellular Ca2+ transients, and Ca2+-modulated protein expression in individual myocytes isolated from the RVOTs. RESULTS: The LV ejection fraction was lower and premature ventricular contraction frequency was higher in the experimental group than in the control group (rats not exposed to myosin peptide). Myocarditis increased the infiltration of inflammatory cells into cardiac tissue and upregulated the expression of NLRP3; these observations were more prominent in the RVOT and RVA than in the LV. Furthermore, experimental rats treated with MCC950 (treatment group) improved their LV ejection fraction and reduced the frequency of premature ventricular contraction. Histopathological analysis revealed higher incidence of abnormal automaticity and pacing-induced ventricular tachycardia in the RVOTs of the experimental group than in those of the control and treatment groups. However, the incidences of these conditions in the RVA and LV were similar across the groups. The RVOT myocytes of the experimental group exhibited lower Ca2+ levels in the sarcoplasmic reticulum, smaller intracellular Ca2+ transients, lower L-type Ca2+ currents, larger late Na+ currents, larger Na+-Ca2+ exchanger currents, higher reactive oxygen species levels, and higher Ca2+/calmodulin-dependent protein kinase II levels than did those of the control and treatment groups. CONCLUSION: Myocarditis may increase the rate of RVOT arrhythmogenesis, possibly through electrical and structural remodeling. These changes may be mitigated by inhibiting NLRP3 signaling.

2.
Transl Res ; 268: 1-12, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38244770

RESUMO

Interleukin (IL)-33, a cytokine involved in immune responses, can activate its receptor, suppression of tumorigenicity 2 (ST2), is elevated during atrial fibrillation (AF). However, the role of IL-33/ST2 signaling in atrial arrhythmia is unclear. This study explored the pathological effects of the IL-33/ST2 axis on atrial remodeling and arrhythmogenesis. Patch clamping, confocal microscopy, and Western blotting were used to analyze the electrical characteristics of and protein activity in atrial myocytes (HL-1) treated with recombinant IL-33 protein and/or ST2-neutralizing antibodies for 48 hrs. Telemetric electrocardiographic recordings, Masson's trichrome staining, and immunohistochemistry staining of the atrium were performed in mice receiving tail vein injections with nonspecific immunoglobulin (control), IL-33, and IL-33 combined with anti-ST2 antibody for 2 weeks. IL-33-treated HL-1 cells had a reduced action potential duration, lower L-type Ca2+ current, greater sarcoplasmic reticulum (SR) Ca2+ content, increased Na+/Ca2+ exchanger (NCX) current, elevation of K+ currents, and increased intracellular calcium transient. IL-33-treated HL-1 myocytes had greater activation of the calcium-calmodulin-dependent protein kinase II (CaMKII)/ryanodine receptor 2 (RyR2) axis and nuclear factor kappa B (NF-κB) / NLR family pyrin domain containing 3 (NLRP3) signaling than did control cells. IL-33 treated cells also had greater expression of Nav1.5, Kv1.5, NCX, and NLRP3 than did control cells. Pretreatment with neutralizing anti-ST2 antibody attenuated IL-33-mediated activation of CaMKII/RyR2 and NF-κB/NLRP3 signaling. IL-33-injected mice had more atrial ectopic beats and increased AF episodes, greater atrial fibrosis, and elevation of NF-κB/NLRP3 signaling than did controls or mice treated with IL-33 combined with anti-ST2 antibody. Thus, IL-33 recombinant protein treatment promotes atrial remodeling through ST2 signaling. Blocking the IL-33/ST2 axis might be an innovative therapeutic approach for patients with atrial arrhythmia and elevated serum IL-33.

3.
Viruses ; 15(12)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38140579

RESUMO

Severe Fever with Thrombocytopenia Syndrome (SFTS), caused by the SFTS Virus (SFTSV), is a global health threat. SFTSV in Taiwan has only been reported in ruminants and wild animals. Thus, we aimed to investigate the infection statuses of dogs and cats, the animals with closer human interactions. Overall, the SFTSV RNA prevalence was 23% (170/735), with dogs showing a 25.9% (111/429) prevalence and cats at 19.3% (59/306) prevalence. Noticeably, the prevalence in stray animals (39.8% 77/193) was significantly higher than in domesticated ones (17.2%, 93/542). Among the four categories analyzed, the highest SFTSV prevalence was found in the stray dogs at 53.9% (120/193), significantly higher than the 24.2% prevalence noted in stray cats. In contrast, domesticated animals exhibited similar prevalence rates, with 17.1% for dogs and 17.2% for cats. It is noteworthy that in the domesticated animal groups, a significantly elevated prevalence (45%, 9/20) was observed among cats exhibiting thrombocytopenia compared to those platelet counts in the reference range (4.8%, 1/21). The high infection rate in stray animals, especially stray dogs, indicated that exposure to various outdoor environments influences the prevalence of infections. Given the higher human interaction with dogs and cats, there is a need for proactive measures to reduce the risk associated with the infection of SFTSV in both animals and humans.


Assuntos
Infecções por Bunyaviridae , Doenças do Gato , Doenças do Cão , Phlebovirus , Febre Grave com Síndrome de Trombocitopenia , Animais , Gatos , Humanos , Cães , Febre Grave com Síndrome de Trombocitopenia/epidemiologia , Febre Grave com Síndrome de Trombocitopenia/veterinária , Infecções por Bunyaviridae/epidemiologia , Infecções por Bunyaviridae/veterinária , Taiwan/epidemiologia , Doenças do Gato/epidemiologia , Doenças do Cão/epidemiologia , Phlebovirus/genética , Animais Selvagens , Animais Domésticos
4.
Int J Mol Sci ; 24(17)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37685906

RESUMO

Glucagon-like peptide-1 (GLP-1) receptor agonists are associated with reduced atrial fibrillation risk, but the mechanisms underlying this association remain unclear. The GLP-1 receptor agonist directly impacts cardiac Ca2+ homeostasis, which is crucial in pulmonary vein (PV, the initiator of atrial fibrillation) arrhythmogenesis. This study investigated the effects of the GLP-1 receptor agonist on PV electrophysiology and Ca2+ homeostasis and elucidated the potential underlying mechanisms. Conventional microelectrodes and whole-cell patch clamp techniques were employed in rabbit PV tissues and single PV cardiomyocytes before and after GLP-1 (7-36) amide, a GLP-1 receptor agonist. Evaluations were conducted both with and without pretreatment with H89 (10 µM, an inhibitor of protein kinase A, PKA), KN93 (1 µM, an inhibitor of Ca2+/calmodulin-dependent protein kinase II, CaMKII), and KB-R7943 (10 µM, an inhibitor of Na+/Ca2+ exchanger, NCX). Results showed that GLP-1 (7-36) amide (at concentrations of 1, 10, and 100 nM) reduced PV spontaneous activity in a concentration-dependent manner without affecting sinoatrial node electrical activity. In single-cell experiments, GLP-1 (7-36) amide (at 10 nM) reduced L-type Ca2+ current, NCX current, and late Na+ current in PV cardiomyocytes without altering Na+ current. Additionally, GLP-1 (7-36) amide (at 10 nM) increased sarcoplasmic reticulum Ca2+ content in PV cardiomyocytes. Furthermore, the antiarrhythmic effects of GLP-1 (7-36) amide on PV automaticity were diminished when pretreated with H89, KN93, or KB-R7943. This suggests that the GLP-1 receptor agonist may exert its antiarrhythmic potential by regulating PKA, CaMKII, and NCX activity, as well as modulating intracellular Ca2+ homeostasis, thereby reducing PV arrhythmogenesis.


Assuntos
Fibrilação Atrial , Conservadores da Densidade Óssea , Veias Pulmonares , Animais , Coelhos , Receptor do Peptídeo Semelhante ao Glucagon 1 , Cálcio , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Antagonistas de Hormônios , Antiarrítmicos , Amidas , Proteínas Quinases Dependentes de AMP Cíclico , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Homeostase
5.
J Assist Reprod Genet ; 40(8): 1855-1864, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37300647

RESUMO

PURPOSE: A live motile sperm sorting device (LensHooke® CA0) developed to prevent the deleterious effects of centrifugation was evaluated comparatively with conventional density-gradient centrifugation (DGC) and microfluidic-based device (Zymot) in sperm selection. METHODS: Semen samples from 239 men were collected. CA0 under different incubation intervals (5, 10, 30, and 60 min) and temperatures (20, 25, and 37℃) was conducted. The sperm quality in CA0-, DGC-, and Zymot-processed samples was then comparatively evaluated. Semen parameters included concentration, motility, morphology, motion kinematics, DNA fragmentation index (DFI), and the rate of acrosome-reacted sperm (AR). RESULTS: Total motility and motile sperm concentration increased in a time- and temperature-dependent manner and the total motility peaked for 30 min at 37℃. In paired analysis, CA0 showed significantly higher total motility (94.0%), progressive motility (90.8%), rapid progressive motility (83.6%), normal morphology (10.3%), and lower DFI (2.4%) and AR (4.7%) than the other two methods in normozoospermic samples (all p < 0.05). For non-normozoospermic samples, CA0 had significantly better results than the other two methods (total motility 89.2%, progressive motility 80.4%, rapid progressive motility 74.2%, normal morphology 8.5%, DFI 4.0%, and AR 4.0%; all p < 0.05). CONCLUSION: CA0 yielded spermatozoa with enhanced sperm fertilization potentials; DFI was minimized in samples processed by CA0. CA0 was effective for both normal and abnormal semen samples due to its consistent selection efficiency.


Assuntos
Microfluídica , Sêmen , Humanos , Masculino , Motilidade dos Espermatozoides , Centrifugação com Gradiente de Concentração/métodos , Espermatozoides , Centrifugação , Levanogestrel , Fertilização , Fragmentação do DNA
6.
Eur J Pharmacol ; 941: 175493, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36621600

RESUMO

BACKGROUND: Excitation-contraction (E-C) coupling, the interaction of action potential duration (APD) and contractility, plays an essential role in arrhythmogenesis. We aimed to investigate the arrhythmogenic role of E-C coupling in the right ventricular outflow tract (RVOT) in the chloroquine-induced long QT syndrome. METHODS: Conventional microelectrodes were used to record electrical and mechanical activity simultaneously under electrical pacing (cycle lengths from 1000-100 ms) in rabbit RVOT tissue preparations before and after chloroquine with and without azithromycin. KB-R7943 (a Na+-Ca2+ exchanger [NCX] inhibitor), ranolazine (a late sodium current inhibitor), or MgSO4 were used to assess their pharmacological responses in the chloroquine-induced long QT syndrome. RESULTS: Sequential infusion of chloroquine and chloroquine plus azithromycin triggered ventricular tachycardia (VT) (33.7%) after rapid pacing compared to baseline (6.7%, p = 0.004). There were greater post-pacing increases of the first occurrence of contractility (ΔContractility) in the VT group (VT vs. non-VT: 521.2 ± 50.5% vs. 306.5 ± 26.8%, p < 0.001). There was no difference in the first occurrence of action potential at 90% repolarization (ΔAPD90) (VT vs. non-VT: 49.7 ± 7.4 ms vs. 51.8 ± 13.1 ms, p = 0.914). Pacing-induced VT could be suppressed to baseline levels by KB-R7943 or MgSO4. Ranolazine did not suppress pacing-induced VT in chloroquine-treated RVOT. ΔContractility was reduced by KB-R7943 and MgSO4, but not by ranolazine. CONCLUSION: ΔContractility (but not ΔAPD) played a crucial role in the genesis of pacing-induced VT in the long QT tissue model, which can be modulated by NCX (but not late sodium current) inhibition or MgSO4.


Assuntos
Síndrome do QT Longo , Taquicardia Ventricular , Animais , Coelhos , Ranolazina/farmacologia , Ranolazina/uso terapêutico , Potenciais de Ação/fisiologia , Azitromicina/efeitos adversos , Arritmias Cardíacas , Síndrome do QT Longo/induzido quimicamente , Taquicardia Ventricular/tratamento farmacológico , Sódio
7.
Appl Microbiol Biotechnol ; 107(2-3): 835-851, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36484827

RESUMO

Orf virus (ORFV), a Parapoxvirus in Poxviridae, infects sheep and goats resulting in contagious pustular dermatitis. ORFV is regarded as a promising viral vector candidate for vaccine development and oncolytic virotherapy. Owing to their potential clinical application, safety concerns have become increasingly important. Deletion of either the OV132 (encoding vascular endothelial growth factor, VEGF) or OV112 (encoding the chemokine binding protein, CBP) genes reduced ORFV infectivity, which has been independently demonstrated in the NZ2 and NZ7 strains, respectively. This study revealed that the VEGF and CBP gene sequences of the local strain (TW/Hoping) shared a similarity of 47.01% with NZ2 and 90.56% with NZ7. Due to the high sequence divergence of these two immunoregulatory genes among orf viral strains, their contribution to the pathogenicity of Taiwanese ORFV isolates was comparatively characterized. Initially, two ORFV recombinants were generated, in which either the VEGF or CBP gene was deleted and replaced with the reporter gene EGFP. In vitro assays indicated that both the VEGF-deletion mutant ORFV-VEGFΔ-EGFP and the CBP deletion mutant ORFV-CBPΔ-EGFP were attenuated in cells. In particular, ORFV-VEGFΔ-EGFP significantly reduced plaque size and virus yield compared to ORFV-CBPΔ-EGFP and the wild-type control. Similarly, in vivo analysis revealed no virus yield in the goat skin biopsy infected by ORFV-VEGFΔ-EGFP, and significantly reduced the virus yield of ORFV-CBPΔ-EGFP relative to the wild-type control. These results confirmed the loss of virulence of both deletion mutants in the Hoping strain, whereas the VEGF-deletion mutant was more attenuated than the CBP deletion strain in both cell and goat models. KEY POINTS: • VEGF and CBP genes are crucial in ORFV pathogenesis in the TW/Hoping strain • The VEGF-deletion mutant virus was severely attenuated in both cell culture and animal models • Deletion mutant viruses are advantageous vectors for the development of vaccines and therapeutic regimens.


Assuntos
Ectima Contagioso , Vírus do Orf , Animais , Ectima Contagioso/patologia , Cabras , Vírus do Orf/genética , Ovinos , Pele , Fator A de Crescimento do Endotélio Vascular/genética , Genes Virais
8.
Int J Mol Sci ; 23(22)2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36430541

RESUMO

Adrenomedullin, a peptide with vasodilatory, natriuretic, and diuretic effects, may be a novel agent for treating heart failure. Heart failure is associated with an increased risk of atrial fibrillation (AF), but the effects of adrenomedullin on atrial arrhythmogenesis remain unclear. This study investigated whether adrenomedullin modulates the electrophysiology of the atria (AF substrate) or pulmonary vein (PV; AF trigger) arrhythmogenesis. Conventional microelectrode or whole-cell patch clamps were used to study the effects of adrenomedullin (10, 30, and 100 pg/mL) on the electrical activity, mechanical response, and ionic currents of isolated rabbit PV and sinoatrial node tissue preparations and single PV cardiomyocytes. At 30 and 100 pg/mL, adrenomedullin significantly reduced the spontaneous beating rate of the PVs from 2.0 ± 0.4 to 1.3 ± 0.5 and 1.1 ± 0.5 Hz (reductions of 32.9% ± 7.1% and 44.9 ± 8.4%), respectively, and reduced PV diastolic tension by 12.8% ± 4.1% and 14.5% ± 4.1%, respectively. By contrast, adrenomedullin did not affect sinoatrial node beating. In the presence of L-NAME (a nitric oxide synthesis inhibitor, 100 µM), adrenomedullin (30 pg/mL) did not affect the spontaneous beating rate or diastolic tension of the PVs. In the single-cell experiments, adrenomedullin (30 pg/mL) significantly reduced the L-type calcium current (ICa-L) and reverse-mode current of the sodium-calcium exchanger (NCX). Adrenomedullin reduces spontaneous PV activity and PV diastolic tension by reducing ICa-L and NCX current and thus may be useful for treating atrial tachyarrhythmia.


Assuntos
Fibrilação Atrial , Insuficiência Cardíaca , Veias Pulmonares , Animais , Coelhos , Adrenomedulina/farmacologia , Átrios do Coração
9.
Exp Ther Med ; 24(6): 720, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36340605

RESUMO

Mirabegron increases atrial fibrillation (AF) risk. The left atrium (LA) is the most critical 'substrate' for AF and has higher arrhythmogenesis compared with the right atrium (RA). The present study aimed to investigate the electrophysiological and arrhythmogenic effects of mirabegron on the LA and RA and clarify the potential underlying mechanisms. Conventional microelectrodes, a whole-cell patch clamp and a confocal microscope were used in rabbit LA and RA preparations or single LA and RA myocytes before and after mirabegron administration with or without cotreatment with KT5823 [a cyclic adenosine monophosphate (cAMP)-dependent protein kinase inhibitor]. The baseline action potential duration at repolarization extents of 20 and 50% (but not 90%) were shorter in the LA than in the RA. Mirabegron at 0.1 and 1 µM (but not 0.01 µM) reduced the action potential duration at repolarization extents of 20 and 50% in the LA and RA. Mirabegron (0.1 µM) increased the occurrence of tachypacing-induced burst firing in the LA but not in the RA, where it was suppressed by KT5823 (1 µM). Mirabegron (0.1 µM) increased the L-type Ca2+ current (ICa-L), ultrarapid component of delayed rectifier K+ current (IKur), Ca2+ transients and sarcoplasmic reticulum Ca2+ content but reduced transient outward K+ current (Ito) in the LA myocytes. However, mirabegron did not change the Na+ current and delayed rectifier K+ current in the LA myocytes. Moreover, pretreatment with KT5823 (1 µM) inhibited the effects of mirabegron on ICa-L, Ito and IKur in the LA myocytes. Furthermore, in the RA myocytes, mirabegron reduced ICa-L but did not change Ito. In conclusion, mirabegron differentially regulates electrophysiological characteristics in the LA and RA. Through the activation of the cAMP-dependent protein kinase pathway and induction of Ca2+ dysregulation, mirabegron may increase LA arrhythmogenesis, leading to increased AF risk.

10.
Int J Mol Sci ; 23(19)2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36232308

RESUMO

Atrial arrhythmias are considered prominent phenomena in pulmonary arterial hypertension (PAH) resulting from atrial electrical and structural remodeling. Endothelin (ET)-1 levels correlate with PAH severity and are associated with atrial remodeling and arrhythmia. In this study, hemodynamic measurement, western blot analysis, and histopathology were performed in the control and monocrotaline (MCT, 60 mg/kg)-induced PAH rabbits. Conventional microelectrodes were used to simultaneously record the electrical activity in the isolated sinoatrial node (SAN) and right atrium (RA) tissue preparations before and after ET-1 (10 nM) or BQ-485 (an ET-A receptor antagonist, 100 nM) perfusion. MCT-treated rabbits showed an increased relative wall thickness in the pulmonary arterioles, mean cell width, cross-sectional area of RV myocytes, and higher right ventricular systolic pressure, which were deemed to have PAH. Compared to the control, the spontaneous beating rate of SAN-RA preparations was faster in the MCT-induced PAH group, which can be slowed down by ET-1. MCT-induced PAH rabbits had a higher incidence of sinoatrial conduction blocks, and ET-1 can induce atrial premature beats or short runs of intra-atrial reentrant tachycardia. BQ 485 administration can mitigate ET-1-induced RA arrhythmogenesis in MCT-induced PAH. The RA specimens from MCT-induced PAH rabbits had a smaller connexin 43 and larger ROCK1 and phosphorylated Akt than the control, and similar PKG and Akt to the control. In conclusion, ET-1 acts as a trigger factor to interact with the arrhythmogenic substrate to initiate and maintain atrial arrhythmias in PAH. ET-1/ET-A receptor/ROCK signaling may be a target for therapeutic interventions to treat PAH-induced atrial arrhythmias.


Assuntos
Monocrotalina , Hipertensão Arterial Pulmonar , Animais , Arritmias Cardíacas , Conexina 43/farmacologia , Modelos Animais de Doenças , Endotelina-1 , Hipertensão Pulmonar Primária Familiar/patologia , Monocrotalina/toxicidade , Proteínas Proto-Oncogênicas c-akt , Artéria Pulmonar/patologia , Coelhos
11.
Europace ; 23(11): 1837-1846, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-33837408

RESUMO

AIMS: Inflammation plays a role in the pathogenesis of atrial fibrillation (AF). Pericarditis enhanced atrial arrhythmogenesis, but the role of the pericardium remains unclear in AF. Activation of the toll-like receptor 4 (TLR4) by binding to lipopolysaccharide (LPS) promotes cardiac electrical remodelling. In this study, we hypothesized that pericarditis may induce atrial arrhythmogenesis via pericardium-myocardium interactions by TLR4 signalling. METHODS AND RESULTS: Pericarditis was induced in rabbits by injecting LPS (1-2 mg/kg) into the pericardium. Conventional microelectrodes were used to record the action potentials of left atrial (LA) posterior walls (LAPWs) and LA appendages (LAAs) with and without attached pericardium in the control or pericarditis-induced rabbits. Cytokine array was used to measure the expression levels of proinflammatory cytokines in control and LPS-treated pericardium. Compared with the controls, the LPS-treated pericardium had higher expressions of IL-1α, IL-8, and MIP-1ß. Rapid atrial pacing-induced burst firing in LPS-treated LAPWs and LAAs, and in control LAPWs (but not in LAAs). The incidence of pacing-induced spontaneous activity and burst firing was increased by LPS-treated pericardium but was attenuated by the control pericardium. Moreover, burst firing induced by LPS-treated pericardium was blocked upon administration of the TLR4 inhibitor, TAK-242 (100 ng/mL), ryanodine receptor inhibitor (ryanodine, 3 µM), or calmodulin kinase II inhibitor (KN-93, 1 µM). CONCLUSIONS: Healthy and inflamed pericardium differently modulate LPS-induced atrial arrhythmogenesis. Targeting pericardium via TLR4 signalling may be a novel therapeutic strategy for AF.


Assuntos
Fibrilação Atrial , Lipopolissacarídeos , Animais , Fibrilação Atrial/induzido quimicamente , Fibrilação Atrial/tratamento farmacológico , Humanos , Lipopolissacarídeos/efeitos adversos , Miocárdio/metabolismo , Pericárdio , Coelhos , Receptor 4 Toll-Like/uso terapêutico
12.
Polymers (Basel) ; 13(1)2020 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-33375390

RESUMO

Wound healing is a complex process that requires specific interactions between multiple cells such as fibroblasts, mesenchymal, endothelial, and neural stem cells. Recent studies have shown that calcium silicate (CS)-based biomaterials can enhance the secretion of growth factors from fibroblasts, which further increased wound healing and skin regeneration. In addition, gelatin methacrylate (GelMa) is a compatible biomaterial that is commonly used in tissue engineering. However, it has low mechanical properties, thus restricting its fullest potential for clinical applications. In this study, we infused Si ions into GelMa hydrogel and assessed for its feasibility for skin regeneration applications by observing for its influences on human dermal fibroblasts (hDF). Initial studies showed that Si could be successfully incorporated into GelMa, and printability was not affected. The degradability of Si-GelMa was approximately 20% slower than GelMa hydrogels, thus allowing for better wound healing and regeneration. Furthermore, Si-GelMa enhanced cellular adhesion and proliferation, therefore leading to the increased secretion of collagen I other important extracellular matrix (ECM) remodeling-related proteins including Ki67, MMP9, and decorin. This study showed that the Si-GelMa hydrogels were able to enhance the activity of hDF due to the gradual release of Si ions, thus making it a potential candidate for future skin regeneration clinical applications.

13.
Cytotherapy ; 22(7): 388-397, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32414635

RESUMO

BACKGROUND AIMS: Recent technical and clinical advances with cell-based therapies (CBTs) hold great promise in the treatment of patients with rare diseases and those with high unmet medical need. Currently the majority of CBTs are developed and manufactured in specialized academic facilities. Due to small scale, unique characteristics and specific supply chain, CBT manufacturing is considered costly compared to more conventional medicinal products. As a result, biomedical researchers and clinicians are increasingly faced with cost considerations in CBT development. The objective of this research was to develop a costing framework and methodology for academic and other small-scale facilities that manufacture cell-based therapies. METHODS: We conducted an international multi-center costing study in four facilities in Europe using eight CBTs as case studies. This study includes costs from cell or tissue procurement to release of final product for clinical use. First, via interviews with research scientists, clinicians, biomedical scientists, pharmacists and technicians, we designed a high-level costing framework. Next, we developed a more detailed uniform methodology to allocate cost items. Costs were divided into steps (tissue procurement, manufacturing and fill-finish). The steps were each subdivided into cost categories (materials, equipment, personnel and facility), and each category was broken down into facility running (fixed) costs and operational (variable) costs. The methodology was tested via the case studies and validated in developer interviews. Costs are expressed in 2018 euros (€). RESULTS: The framework and methodology were applicable across facilities and proved sensitive to differences in product and facility characteristics. Case study cost estimates ranged between €23 033 and €190 799 Euros per batch, with batch yield varying between 1 and 88 doses. The cost estimations revealed hidden costs to developers and provided insights into cost drivers to help design manufacturing best practices. CONCLUSIONS: This framework and methodology provide step-by-step guidance to estimate manufacturing costs specifically for cell-based therapies manufactured in academic and other small-scale enterprises. The framework and methodology can be used to inform and plan cost-conscious strategies for CBTs.


Assuntos
Academias e Institutos , Terapia Baseada em Transplante de Células e Tecidos/economia , Custos e Análise de Custo , Comércio , Europa (Continente) , Instalações de Saúde , Humanos
14.
J Med Syst ; 44(2): 54, 2020 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31927706

RESUMO

Sepsis mortality is heavily influenced by the quality of care in hospitals. Comparing risk-standardized mortality rate (RSMR) of sepsis patients in different states in the United States has potentially important clinical and policy implications. In the current study, we aimed to compare national sepsis RSMR using an interactive web-based dashboard. We analyzed sepsis mortality using the National Inpatient Sample Database of the US. The RSMR was calculated by the hierarchical logistic regression model. We wrote the interactive web-based dashboard using the Shiny framework, an R package that integrates R-based statistics computation and graphics generation. Visual summarizations (e.g., heat map, and time series chart), and interactive tools (e.g., year selection, automatic year play, map zoom, copy or print data, ranking data by name or value, and data search) were implemented to enhance user experience. The web-based dashboard (https://sepsismap.shinyapps.io/index2/) is cross-platform and publicly available to anyone with interest in sepsis outcomes, health inequality, and administration of state/federal healthcare. After extrapolation to the national level, approximately 35 million hospitalizations were analyzed for sepsis mortality each year. Eight years of sepsis mortality data were summarized into four easy to understand dimensions: Sepsis Identification Criteria; Sepsis Mortality Predictors; RSMR Map; RSMR Trend. Substantial variation in RSMR was observed for different states in the US. This web-based dashboard allows anyone to visualize the substantial variation in RSMR across the whole US. Our work has the potential to support healthcare transparency, information diffusion, health decision-making, and the formulation of new public policies.


Assuntos
Registros Eletrônicos de Saúde/estatística & dados numéricos , Mortalidade Hospitalar , Armazenamento e Recuperação da Informação/métodos , Sepse/mortalidade , Apresentação de Dados , Feminino , Disparidades nos Níveis de Saúde , Humanos , Modelos Logísticos , Masculino , Avaliação de Processos e Resultados em Cuidados de Saúde , Medição de Risco , Estados Unidos
15.
Int J Mol Sci ; 20(18)2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31547262

RESUMO

Cell migration is an important process involved in wound healing, tissue development, and so on. Many studies have been conducted to explore how certain chemicals and electric fields induce cell movements in specific directions, which are phenomena termed chemotaxis and electrotaxis, respectively. However, phototaxis, the directional migration of cells or organisms toward or away from light, is rarely investigated due to the difficulty of generating a precise and controllable light gradient. In this study, we designed and fabricated a microfluidic chip for simultaneously culturing cells and generating a blue light gradient for guiding cell migration. A concentration gradient was first established inside this chip, and by illuminating it with a blue light-emitting diode (LED), a blue light gradient was generated underneath. Cell migration in response to this light stimulus was observed. It was found that lung cancer cells migrated to the dark side of the gradient, and the intracellular reactive oxygen species (ROS) was proportional to the intensity of the blue light.


Assuntos
Movimento Celular , Dispositivos Lab-On-A-Chip , Neoplasias Pulmonares/metabolismo , Células A549 , Animais , Técnicas de Cultura de Células/instrumentação , Desenho de Equipamento , Humanos , Luz , Camundongos , Células NIH 3T3 , Espécies Reativas de Oxigênio/metabolismo
16.
JMIR Med Inform ; 7(3): e13329, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31271151

RESUMO

BACKGROUND: Conventional systems of drug surveillance lack a seamless workflow, which makes it crucial to have an active drug surveillance system that proactively assesses adverse drug events. OBJECTIVE: The aim of this study was to develop a seamless, Web-based workflow for comparing the safety and effectiveness of drugs in a database of electronic medical records. METHODS: We proposed a comprehensive integration process for cohort surveillance using the National Taiwan University Hospital Clinical Surveillance System (NCSS). We studied a practical application of the NCSS that evaluates the drug safety and effectiveness of novel oral anticoagulants (NOACs) and warfarin by cohort tree analysis in an efficient and interoperable platform. RESULTS: We demonstrated a practical example of investigating the differences in effectiveness and safety between NOACs and warfarin in patients with nonvalvular atrial fibrillation (AF) using the NCSS. We efficiently identified 2357 patients with nonvalvular AF with newly prescribed oral anticoagulants between 2010 and 2015 and further developed 1 main cohort and 2 subcohorts for separately measuring ischemic stroke as the clinical effectiveness outcome and intracranial hemorrhage (ICH) as the safety outcome. In the subcohort of ischemic stroke, NOAC users exhibited a significantly lower risk of ischemic stroke than warfarin users after adjusting for age, sex, comorbidity, and comedication in an intention-to-treat (ITT) analysis (P=.01) but did not exhibit a significantly distinct risk in an as-treated (AT) analysis (P=.12) after the 2-year follow-up. In the subcohort of ICH, NOAC users did not exhibit a different risk of ICH both in ITT (P=.68) and AT analyses (P=.15). CONCLUSIONS: With a seamless and Web-based workflow, the NCSS can serve the critical role of forming associations between evidence and the real world at a medical center in Taiwan.

17.
Medicine (Baltimore) ; 98(23): e15964, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31169724

RESUMO

Knee osteoarthritis is a degenerative disease occurring in elderly people worldwide. For severe knee osteoarthritis, total knee replacement is the final treatment option. Traditional Chinese medicine (TCM) is popular in Taiwan and has been shown to exert therapeutic effects on knee osteoarthritis. We investigated the long-term clinical effects of TCM for reducing the need for total knee replacement risk in patients with knee osteoarthritis.We used the National Health Insurance Research Database to conduct a retrospective study of patients with knee osteoarthritis between 1997 and 2003 in Taiwan. Data from the date of diagnosis of knee osteoarthritis to total knee replacement were assessed using the Cox regression proportional hazards model, and the Kaplan-Meier survival curve was used to determine the association between total knee replacement risk and TCM use.A total of 34,231 patients with knee osteoarthritis, who were diagnosed by orthopedic or rehabilitation physicians between 1997 and 2003 were included. Patients were categorized into 2 groups: 26,257 (76.7%) were TCM users and 7974 (23.3%) were TCM non-users. The mean follow-up period was 9.26 years. Multivariate regression demonstrated that using TCM may decrease the need for total knee replacement in patients with knee osteoarthritis (adjusted hazards ratio [aHR] = 0.69, 95% confidence interval [95% CI]: 0.64-0.77) compared with TCM non-users. A relationship between longer TCM use and reduced total knee replacement use was observed, especially in patients who used TCM for ≥120 days (aHR = 0.49, 95% CI: 0.42-0.56).The results of this study suggested that TCM is associated with a reduced risk of total knee replacement in patients with knee osteoarthritis, with enhanced benefits from longer durations of TCM use.


Assuntos
Artroplastia do Joelho/estatística & dados numéricos , Medicina Tradicional Chinesa/métodos , Osteoartrite do Joelho/terapia , Idoso , Bases de Dados Factuais , Feminino , Humanos , Seguro Saúde , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Taiwan , Fatores de Tempo , Resultado do Tratamento
18.
J Virol ; 93(7)2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30651363

RESUMO

Orf virus (ORFV) infects sheep and goats and is also an important zoonotic pathogen. The viral protein OV20.0 has been shown to suppress innate immunity by targeting the double-stranded RNA (dsRNA)-activated protein kinase (PKR) by multiple mechanisms. These mechanisms include a direct interaction with PKR and binding with two PKR activators, dsRNA and the cellular PKR activator (PACT), which ultimately leads to the inhibition of PKR activation. In the present study, we identified a novel association between OV20.0 and adenosine deaminase acting on RNA 1 (ADAR1). OV20.0 bound directly to the dsRNA binding domains (RBDs) of ADAR1 in the absence of dsRNA. Additionally, OV20.0 preferentially interacted with RBD1 of ADAR1, which was essential for its dsRNA binding ability and for the homodimerization that is critical for intact adenosine-to-inosine (A-to-I)-editing activity. Finally, the association with OV20.0 suppressed the A-to-I-editing ability of ADAR1, while ADAR1 played a proviral role during ORFV infection by inhibiting PKR phosphorylation. These observations revealed a new strategy used by OV20.0 to evade antiviral responses via PKR.IMPORTANCE Viruses evolve specific strategies to counteract host innate immunity. ORFV, an important zoonotic pathogen, encodes OV20.0 to suppress PKR activation via multiple mechanisms, including interactions with PKR and two PKR activators. In this study, we demonstrated that OV20.0 interacts with ADAR1, a cellular enzyme responsible for converting adenosine (A) to inosine (I) in RNA. The RNA binding domains, but not the catalytic domain, of ADAR1 are required for this interaction. The OV20.0-ADAR1 association affects the functions of both proteins; OV20.0 suppressed the A-to-I editing of ADAR1, while ADAR1 elevated OV20.0 expression. The proviral role of ADAR1 is likely due to the inhibition of PKR phosphorylation. As RNA editing by ADAR1 contributes to the stability of the genetic code and the structure of RNA, these observations suggest that in addition to serving as a PKR inhibitor, OV20.0 might modulate ADAR1-dependent gene expression to combat antiviral responses or achieve efficient viral infection.


Assuntos
Adenosina Desaminase/genética , Vírus do Orf/genética , RNA Viral/genética , Proteínas de Ligação a RNA/genética , Proteínas Virais/genética , Replicação Viral/genética , Células A549 , Adenosina/genética , Animais , Linhagem Celular , Linhagem Celular Tumoral , Ectima Contagioso/genética , Proteínas Ativadoras de GTPase/genética , Células HEK293 , Humanos , Imunidade Inata/genética , Inosina/genética , Fosforilação/genética , Edição de RNA/genética , RNA de Cadeia Dupla/genética , Ovinos
19.
Sci Total Environ ; 651(Pt 1): 1058-1066, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30266051

RESUMO

Due to rapid industrialization and urbanization, the environment is exposed to many chemicals from natural or anthropogenic sources. The contaminants impact eco-system and human health via food chain. Animals, including humans, are likely to accumulate contaminants in their bodies from direct exposure or feeding behavior, resulting in toxicity. Therefore, evaluation of the toxicity of contaminants is an important issue. Metals are highly toxic but the toxicity depends on many factors, including the valance and the complex form of metals, the organic matter level in the environment, the reducing/oxidizing condition of the environment, and etc. Since the level of metal amount does not directly correlate to bioavailability, cell culture is usually used for toxicity evaluation. In this study, a microfluidic chip was developed to evaluate the cell toxicity from exposure to metals, copper and thallium. Compared to traditional cytotoxicity assay using static state culture with tetrazolium reagent, this microfluidic chip can generate various shear stresses by changing geometry of culture areas or flow rate. Enhancement of shear stresses could increase cell sensitivity toward metal exposure. Therefore, this platform provides a more sensitive platform for quantitative analysis of cell toxicity and could be applied to evaluate toxicity from environmental samples.

20.
J Med Internet Res ; 20(4): e142, 2018 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-29691201

RESUMO

BACKGROUND: Traditional clinical surveillance relied on the results from clinical trials and observational studies of administrative databases. However, these studies not only required many valuable resources but also faced a very long time lag. OBJECTIVE: This study aimed to illustrate a practical application of the National Taiwan University Hospital Clinical Surveillance System (NCSS) in the identification of patients with an osteoporotic fracture and to provide a high reusability infrastructure for longitudinal clinical data. METHODS: The NCSS integrates electronic medical records in the National Taiwan University Hospital (NTUH) with a data warehouse and is equipped with a user-friendly interface. The NCSS was developed using professional insight from multidisciplinary experts, including clinical practitioners, epidemiologists, and biomedical engineers. The practical example identifying the unmet treatment needs for patients encountering major osteoporotic fractures described herein was mainly achieved by adopting the computerized workflow in the NCSS. RESULTS: We developed the infrastructure of the NCSS, including an integrated data warehouse and an automatic surveillance workflow. By applying the NCSS, we efficiently identified 2193 patients who were newly diagnosed with a hip or vertebral fracture between 2010 and 2014 at NTUH. By adopting the filter function, we identified 1808 (1808/2193, 82.44%) patients who continued their follow-up at NTUH, and 464 (464/2193, 21.16%) patients who were prescribed anti-osteoporosis medications, within 3 and 12 months post the index date of their fracture, respectively. CONCLUSIONS: The NCSS systems can integrate the workflow of cohort identification to accelerate the survey process of clinically relevant problems and provide decision support in the daily practice of clinical physicians, thereby making the benefit of evidence-based medicine a reality.


Assuntos
Osteoporose/complicações , Fraturas por Osteoporose/terapia , Vigilância em Saúde Pública/métodos , Idoso , Estudos de Coortes , Bases de Dados Factuais , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Fraturas por Osteoporose/patologia , Inquéritos e Questionários
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