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BACKGROUND: Kawasaki disease (KD) is an acute febrile illness and systemic vasculitis often associated with cardiac sequelae, including arrhythmias. Abundant evidence indicates a central role for IL (interleukin)-1 and TNFα (tumor necrosis factor-alpha) signaling in the formation of arterial lesions in KD. We aimed to investigate the mechanisms underlying the development of electrophysiological abnormalities in a murine model of KD vasculitis. METHODS: Lactobacillus casei cell wall extract-induced KD vasculitis model was used to investigate the therapeutic efficacy of clinically relevant IL-1Ra (IL-1 receptor antagonist) and TNFα neutralization. Echocardiography, in vivo electrophysiology, whole-heart optical mapping, and imaging were performed. RESULTS: KD vasculitis was associated with impaired ejection fraction, increased ventricular tachycardia, prolonged repolarization, and slowed conduction velocity. Since our transcriptomic analysis of human patients showed elevated levels of both IL-1ß and TNFα, we asked whether either cytokine was linked to the development of myocardial dysfunction. Remarkably, only inhibition of IL-1 signaling by IL-1Ra but not TNFα neutralization was able to prevent changes in ejection fraction and arrhythmias, whereas both IL-1Ra and TNFα neutralization significantly improved vasculitis and heart vessel inflammation. The treatment of L casei cell wall extract-injected mice with IL-1Ra also restored conduction velocity and improved the organization of Cx43 (connexin 43) at the intercalated disk. In contrast, in mice with gain of function of the IL-1 signaling pathway, L casei cell wall extract induced spontaneous ventricular tachycardia and premature deaths. CONCLUSIONS: Our results characterize the electrophysiological abnormalities associated with L casei cell wall extract-induced KD and show that IL-1Ra is more effective in preventing KD-induced myocardial dysfunction and arrhythmias than anti-TNFα therapy. These findings support the advancement of clinical trials using IL-1Ra in patients with KD.
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Cardiomiopatias , Síndrome de Linfonodos Mucocutâneos , Taquicardia Ventricular , Vasculite , Humanos , Animais , Camundongos , Síndrome de Linfonodos Mucocutâneos/complicações , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Proteína Antagonista do Receptor de Interleucina 1/farmacologia , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Fator de Necrose Tumoral alfa , Modelos Animais de Doenças , Interleucina-1beta/metabolismo , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/prevenção & controle , Taquicardia Ventricular/prevenção & controle , Taquicardia Ventricular/complicaçõesRESUMO
Thermococcus onnurineus NA1, a hyperthermophilic carboxydotrophic archaeon, produces H2 through CO oxidation catalyzed by proteins encoded in a carbon monoxide dehydrogenase (CODH) gene cluster. TON_1525 with a DNA-binding helix-turn-helix (HTH) motif is a putative repressor regulating the transcriptional expression of the codh gene cluster. The T55I mutation in TON_1525 led to enhanced H2 production accompanied by the increased expression of genes in the codh cluster. Here, TON_1525 was demonstrated to be a dimer. Monomeric TON_1525 adopts a novel 'eighth note' symbol-like fold (referred to as 'eighth note' fold regulator, EnfR), and the dimerization mode of EnfR is unique in that it has no resemblance to structures in the Protein Data Bank. According to footprinting and gel shift assays, dimeric EnfR binds to a 36-bp pseudo-palindromic inverted repeat in the promoter region of the codh gene cluster, which is supported by an in silico EnfR/DNA complex model and mutational studies revealing the implication of N-terminal loops as well as HTH motifs in DNA recognition. The DNA-binding affinity of the T55I mutant was lowered by â¼15-fold, for which the conformational change of N-terminal loops is responsible. In addition, transcriptome analysis suggested that EnfR could regulate diverse metabolic processes besides H2 production.
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The adolescent social experience is essential for the maturation of the prefrontal cortex in mammalian species. However, it still needs to be determined which cortical circuits mature with such experience and how it shapes adult social behaviors in a sex-specific manner. Here, we examined social-approaching behaviors in male and female mice after postweaning social isolation (PWSI), which deprives social experience during adolescence. We found that the PWSI, particularly isolation during late adolescence, caused an abnormal increase in social approaches (hypersociability) only in female mice. We further found that the PWSI female mice showed reduced parvalbumin (PV) expression in the left orbitofrontal cortex (OFCL). When we measured neural activity in the female OFCL, a substantial number of neurons showed higher activity when mice sniffed other mice (social sniffing) than when they sniffed an object (object sniffing). Interestingly, the PWSI significantly reduced both the number of activated neurons and the activity level during social sniffing in female mice. Similarly, the CRISPR/Cas9-mediated knockdown of PV in the OFCL during late adolescence enhanced sociability and reduced the social sniffing-induced activity in adult female mice via decreased excitability of PV+ neurons and reduced synaptic inhibition in the OFCL Moreover, optogenetic activation of excitatory neurons or optogenetic inhibition of PV+ neurons in the OFCL enhanced sociability in female mice. Our data demonstrate that the adolescent social experience is critical for the maturation of PV+ inhibitory circuits in the OFCL; this maturation shapes female social behavior via enhancing social representation in the OFCL SIGNIFICANCE STATEMENT Adolescent social isolation often changes adult social behaviors in mammals. Yet, we do not fully understand the sex-specific effects of social isolation and the brain areas and circuits that mediate such changes. Here, we found that adolescent social isolation causes three abnormal phenotypes in female but not male mice: hypersociability, decreased PV+ neurons in the left orbitofrontal cortex (OFCL), and decreased socially evoked activity in the OFCL Moreover, parvalbumin (PV) deletion in the OFCL in vivo caused the same phenotypes in female mice by increasing excitation compared with inhibition within the OFCL Our data suggest that adolescent social experience is required for PV maturation in the OFCL, which is critical for evoking OFCL activity that shapes social behaviors in female mice.
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Neurônios , Parvalbuminas , Masculino , Camundongos , Animais , Feminino , Parvalbuminas/metabolismo , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Comportamento Social , Isolamento Social , Interneurônios/fisiologia , MamíferosRESUMO
Piezo1 mechanosensitive ion channel plays a important role in vascular physiology and disease. This study aimed to elucidate the altered signaling elicited by Piezo1 activation in the arteries of type 2 diabetes. Ten- to 12-week-old male C57BL/6 (control) and type 2 diabetic mice (db-/db-) were used. The second-order mesenteric arteries (~ 150 µm) were used for isometric tension experiments. Western blot analysis and immunofluorescence staining were performed to observe protein expression. Piezo1 was significantly decreased in mesenteric arteries of type 2 diabetic mice compared to control mice, as analyzed by western blot and immunofluorescence staining. Piezo1 agonist, Yoda1, concentration-dependently induced relaxation of mesenteric arteries in both groups. Interestingly, the relaxation response was significantly greater in control mice than in db-/db- mice. The removal of endothelium reduced relaxation responses induced by Yoda1, which was greater in control mice than db-/db- mice. Furthermore, the relaxation response was reduced by pre-treatment with various types of K+ channel blockers in endothelium-intact arteries in control mice. In endothelium-denuded arteries, pre-incubation with charybdotoxin, an Ca2+-activated K+ channel (BKCa channel) blocker, significantly attenuated Yoda1-induced relaxation in db-/db- mice, while there was no effect in control mice. Co-immunofluorescence staining showed co-localization of Piezo1 and BKCa channel was more pronounced in db-/db- mice than in control mice. These results indicate that the vascular responses induced by Piezo1 activation are different in the mesenteric resistance arteries in type 2 diabetic mice.
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BACKGROUND: We recently reported that the dopamine (DA) analogue CA140 modulates neuroinflammatory responses in lipopolysaccharide-injected wild-type (WT) mice and in 3-month-old 5xFAD mice, a model of Alzheimer's disease (AD). However, the effects of CA140 on Aß/tau pathology and synaptic/cognitive function and its molecular mechanisms of action are unknown. METHODS: To investigate the effects of CA140 on cognitive and synaptic function and AD pathology, 3-month-old WT mice or 8-month-old (aged) 5xFAD mice were injected with vehicle (10% DMSO) or CA140 (30 mg/kg, i.p.) daily for 10, 14, or 17 days. Behavioral tests, ELISA, electrophysiology, RNA sequencing, real-time PCR, Golgi staining, immunofluorescence staining, and western blotting were conducted. RESULTS: In aged 5xFAD mice, a model of AD pathology, CA140 treatment significantly reduced Aß/tau fibrillation, Aß plaque number, tau hyperphosphorylation, and neuroinflammation by inhibiting NLRP3 activation. In addition, CA140 treatment downregulated the expression of cxcl10, a marker of AD-associated reactive astrocytes (RAs), and c1qa, a marker of the interaction of RAs with disease-associated microglia (DAMs) in 5xFAD mice. CA140 treatment also suppressed the mRNA levels of s100ß and cxcl10, markers of AD-associated RAs, in primary astrocytes from 5xFAD mice. In primary microglial cells from 5xFAD mice, CA140 treatment increased the mRNA levels of markers of homeostatic microglia (cx3cr1 and p2ry12) and decreased the mRNA levels of a marker of proliferative region-associated microglia (gpnmb) and a marker of lipid-droplet-accumulating microglia (cln3). Importantly, CA140 treatment rescued scopolamine (SCO)-mediated deficits in long-term memory, dendritic spine number, and LTP impairment. In aged 5xFAD mice, these effects of CA140 treatment on cognitive/synaptic function and AD pathology were regulated by dopamine D1 receptor (DRD1)/Elk1 signaling. In primary hippocampal neurons and WT mice, CA140 treatment promoted long-term memory and dendritic spine formation via effects on DRD1/CaMKIIα and/or ERK signaling. CONCLUSIONS: Our results indicate that CA140 improves neuronal/synaptic/cognitive function and ameliorates Aß/tau pathology and neuroinflammation by modulating DRD1 signaling in primary hippocampal neurons, primary astrocytes/microglia, WT mice, and aged 5xFAD mice.
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Doença de Alzheimer , Peptídeos beta-Amiloides , Camundongos Transgênicos , Doenças Neuroinflamatórias , Receptores de Dopamina D1 , Transdução de Sinais , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Camundongos , Peptídeos beta-Amiloides/metabolismo , Doenças Neuroinflamatórias/tratamento farmacológico , Doenças Neuroinflamatórias/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Receptores de Dopamina D1/metabolismo , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Sinapses/patologia , Cognição/efeitos dos fármacos , Dopamina/metabolismo , Camundongos Endogâmicos C57BL , Masculino , HumanosRESUMO
Circular dichroism (CD) spectroscopy is widely used to characterize the secondary structure composition of proteins. To derive accurate and detailed structural information from the CD spectra, we have developed the Beta Structure Selection (BeStSel) method (PNAS, 112, E3095), which can handle the spectral diversity of ß-structured proteins. The BeStSel webserver provides this method with useful accessories to the community with the main goal to analyze single or multiple protein CD spectra. Uniquely, BeStSel provides information on eight secondary structure components including parallel ß-structure and antiparallel ß-sheets with three different groups of twist. It overperforms any available method in accuracy and information content, moreover, it is capable of predicting the protein fold down to the topology/homology level of the CATH classification. A new module of the webserver helps to distinguish intrinsically disordered proteins by their CD spectrum. Secondary structure calculation for uploaded PDB files will help the experimental verification of protein MD and in silico modelling using CD spectroscopy. The server also calculates extinction coefficients from the primary sequence for CD users to determine the accurate protein concentrations which is a prerequisite for reliable secondary structure determination. The BeStSel server can be freely accessed at https://bestsel.elte.hu.
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Proteínas Intrinsicamente Desordenadas , Estrutura Secundária de Proteína , Simulação por Computador , Análise Espectral , Dicroísmo CircularRESUMO
PURPOSE: Virtual reality technology has been used to establish a risk-free environment in which students can practice psychiatric nursing. A quasi-experimental study was conducted to examine the effects of a virtual reality (VR) based mental health nursing simulation on practice performance of undergraduate nursing students. METHODS: A quasi-experimental, pre- and post-test design was used. A total of 68 students were randomly assigned to an experimental group (n = 32) and a control group (n = 36). The control group received conventional simulation using text scenario-based role play. The intervention group received VR software consisting of 360° video clips and related quiz questions. RESULTS: The self-reported perceived competency in nursing performance showed no statistically significant improvement in the experimental group, whereas the control group showed a statistically significant improvement in symptom management (t = 2.84, p = 0.007) and nurse-patient interaction (t = 2.10, p = 0.043). Scores from the assessor showed better performance scores in the experimental group in symptom management (t = -2.62, p = 0.011), violence risk management (t = -3.42, p = 0.001), and nurse-patient interaction (t = -3.12, p = 0.003). CONCLUSIONS: The findings of this study indicate the potential of using VR for optimized mental health nursing simulation. VR technology allowed realistic experiences which may ensure students have a more comprehensive understanding of mentally ill patients and in doing so, overcome barriers of traditional simulation, resulting in better learning outcomes.
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Enfermagem Psiquiátrica , Realidade Virtual , Humanos , Enfermagem Psiquiátrica/educação , Enfermagem Psiquiátrica/métodos , Feminino , Masculino , Adulto Jovem , Adulto , Bacharelado em Enfermagem/métodos , Estudantes de Enfermagem/psicologia , Estudantes de Enfermagem/estatística & dados numéricosRESUMO
In the development of new drugs, typical polymer- or macromolecule-based nanocarriers suffer from manufacturing process complexity, unwanted systematic toxicity, and low loading capacity. However, carrier-free nanomedicines have made outstanding progress in drug delivery and pharmacokinetics, demonstrating most of the advantages associated with nanoparticles when applied in targeted anticancer therapy. Here, to overcome the problems of nanocarriers and conventional cytotoxic drugs, we developed a novel, carrier-free, self-assembled prodrug consisting of a hydrophobic palmitic (16-carbon chain n-hexadecane chain) moiety and hydrophilic group (or moiety) which is included in a caspase-3-specific cleavable peptide (Asp-Glu-Val-Asp, DEVD) and a cytotoxic drug (doxorubicin, DOX). The amphiphilic conjugate, the palmitic-DEVD-DOX, has the ability to self-assemble into nanoparticles in saline without the need for any carriers or nanoformulations. Additionally, the inclusion of doxorubicin is in its prodrug form and the apoptosis-specific DEVD peptide lead to the reduced side effects of doxorubicin in normal tissue. Furthermore, the carrier-free palmitic-DEVD-DOX nanoparticles could passively accumulate in the tumor tissues of tumor-bearing mice due to an enhanced permeation and retention (EPR) effect. As a result, the palmitic-DEVD-DOX conjugate showed an enhanced therapeutic effect compared with the unmodified DEVD-DOX conjugate. Therefore, this carrier-free palmitic-DEVD-DOX prodrug has great therapeutic potential to treat solid tumors, overcoming the problems of conventional chemotherapy and nanoparticles.
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Antineoplásicos , Nanopartículas , Neoplasias , Pró-Fármacos , Camundongos , Animais , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Peptídeos , Neoplasias/tratamento farmacológicoRESUMO
[Figure: see text].
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Vasos Sanguíneos/metabolismo , Células Dendríticas/metabolismo , Macrófagos/metabolismo , Síndrome de Linfonodos Mucocutâneos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Células Estromais/metabolismo , Animais , Vasos Sanguíneos/citologia , Células Cultivadas , Fibroblastos/metabolismo , Interleucina-1beta/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Síndrome de Linfonodos Mucocutâneos/imunologia , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Receptores Tipo I de Interleucina-1/metabolismoRESUMO
CD19-targeting chimeric antigen receptor (CAR) T cells have become an important therapeutic option for patients with relapsed and refractory B cell malignancies. However, a significant portion of patients still do not benefit from the therapy owing to various resistance mechanisms, including high expression of multiple inhibitory immune checkpoint receptors. Here, we report a lentiviral two-in-one CAR T approach in which two checkpoint receptors are downregulated simultaneously by a dual short hairpin RNA cassette integrated into a CAR vector. Using this system, we evaluated CD19-targeting CAR T cells in the context of four different checkpoint combinations-PD-1/TIM-3, PD-1/LAG-3, PD-1/CTLA-4, and PD-1/TIGIT-and found that CAR T cells with PD-1/TIGIT downregulation uniquely exerted synergistic antitumor effects. Importantly, functional and phenotypic analyses suggested that downregulation of PD-1 enhances short-term effector function, whereas downregulation of TIGIT is primarily responsible for maintaining a less differentiated/exhausted state, providing a potential mechanism for the observed synergy. The PD-1/TIGIT-downregulated CAR T cells generated from diffuse large B cell lymphoma patient-derived T cells also showed robust antitumor activity and significantly improved persistence in vivo. The efficacy and safety of PD-1/TIGIT-downregulated CD19-targeting CAR T cells are currently being evaluated in adult patients with relapsed or refractory large B cell lymphoma (ClinicalTrials.gov: NCT04836507).
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Linfoma Difuso de Grandes Células B , Receptor de Morte Celular Programada 1 , Antígenos CD19 , Regulação para Baixo , Humanos , Imunoterapia Adotiva , Fenótipo , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Linfócitos TRESUMO
Rationale: It remains unclear how gastroesophageal reflux disease (GERD) affects allograft microbial community composition in lung transplant recipients and its impact on lung allograft inflammation and function. Objectives: Our objective was to compare the allograft microbiota in lung transplant recipients with or without clinically diagnosed GERD in the first year after transplant and assess associations between GERD, allograft microbiota, inflammation, and acute and chronic lung allograft dysfunction (ALAD and CLAD). Methods: A total of 268 BAL samples were collected from 75 lung transplant recipients at a single transplant center every 3 months after transplant for 1 year. Ten transplant recipients from a separate transplant center provided samples before and after antireflux Nissen fundoplication surgery. Microbial community composition and density were measured using 16S ribosomal RNA gene sequencing and quantitative polymerase chain reaction, respectively, and inflammatory markers and bile acids were quantified. Measurements and Main Results: We observed a range of allograft community composition with three discernible types (labeled community state types [CSTs] 1-3). Transplant recipients with GERD were more likely to have CST1, characterized by high bacterial density and relative abundance of the oropharyngeal colonizing genera Prevotella and Veillonella. GERD was associated with more frequent transitions to CST1. CST1 was associated with lower inflammatory cytokine concentrations than pathogen-dominated CST3 across the range of microbial densities observed. Cox proportional hazard models revealed associations between CST3 and the development of ALAD/CLAD. Nissen fundoplication decreased bacterial load and proinflammatory cytokines. Conclusions: GERD was associated with a high bacterial density, Prevotella- and Veillonella-dominated CST1. CST3, but not CST1 or GERD, was associated with inflammation and early development of ALAD and CLAD. Nissen fundoplication was associated with a reduction in microbial density in BAL fluid samples, especially the CST1-specific genus, Prevotella.
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Refluxo Gastroesofágico , Transplante de Pulmão , Microbiota , Humanos , Estudos Retrospectivos , Refluxo Gastroesofágico/complicações , Pulmão , Inflamação , AloenxertosRESUMO
Ezetimibe is a lipid-lowering agent that selectively inhibits cholesterol absorption by binding to the Niemann-Pick C1-like 1 (NPC1L1) protein. Although it is well known that administration of ezetimibe in hypercholesterolemia patients reduces the risk of cardiovascular events through attenuation of atherosclerosis, studies on the direct effect of ezetimibe on vascular function are not sufficient. The aim of the present study was to investigate the vascular effects of ezetimibe in rat mesenteric arteries. In the present study, 12-week-old male Sprague Dawley rats were used. After the rats were sacrificed, the second branches of the mesenteric arteries were isolated and cut into 2-3 mm segments and mounted in a multi-wire myography system to measure isometric tension. Ezetimibe reduced vasoconstriction induced by U46619 (500 nM) in endothelium-intact and endothelium-denuded arteries. Ezetimibe-induced vasodilation was not affected by the endothelial nitric oxide synthase (eNOS) inhibitor Nω-Nitro-L-arginine (L-NNA, 300 µM) or the non-selective potassium channel blocker, tetraethylammonium (TEA, 10 mM). Moreover, ezetimibe also completely blocked the contraction induced by an increase in external calcium concentration. Ezetimibe significantly reduced vascular contraction induced by L-type Ca2+ channel activator (Bay K 8644, 30 nM). Treatment with ezetimibe decreased the phosphorylation level of 20 kDa myosin light chain (MLC20) in vascular smooth muscle cells. In the present study, we found that ezetimibe has a significant vasodilatory effect in rat mesenteric resistance arteries. These results suggest that ezetimibe may have beneficial cardiovascular effects beyond its cholesterol-lowering properties.
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Artérias Mesentéricas , Vasodilatação , Humanos , Ratos , Masculino , Animais , Ezetimiba/farmacologia , Ratos Sprague-Dawley , Fosforilação , Proteínas de Membrana TransportadorasRESUMO
Dapagliflozin, a sodium-glucose co-transporter 2 (SGLT2) inhibitor, is an antidiabetic medication that reduces blood glucose. Although it is well known that dapagliflozin has additional benefits beyond glycemic control, such as reducing blood pressure and lowering the risk of cardiovascular events, no sufficient research data are available on the direct effect of dapagliflozin on cardiovascular function. Thus, in this study, we investigated the direct vascular effect of dapagliflozin on isolated rat coronary arteries. The left descending coronary arteries of 13-week-old male Sprague Dawley rats were cut into segments 2-3 mm long and mounted in a multi-wire myography system to measure isometric tension. Dapagliflozin effectively reduced blood vessel constriction induced by U-46619 (500 nM) in coronary arteries regardless of the endothelium. Treatment with an eNOS inhibitor (L-NNA, 100 µM), sGC inhibitor (ODQ, 5 µM), or COX inhibitor (indomethacin, 3 µM) did not affect the vasodilation induced by dapagliflozin. The application of a Ca2+-activated K+ channel (KCa) blocker (TEA, 2 mM), voltage-dependent K+ channel (KV) blocker (4-AP, 2 mM), ATP-sensitive K+ channel blocker (KATP) glibenclamide (3 µM), and inward-rectifier K+ channel (KIR) blocker (BaCl2, 30 µM) did not affect the dapagliflozin-induced vasodilation either. The treatment with dapagliflozin decreased contractile responses induced by the addition of Ca2+, which suggested that the extracellular Ca2+ influx was inhibited by dapagliflozin. Treatment with dapagliflozin decreased the phosphorylation level of the 20 kDa myosin light chain (MLC20) in vascular smooth muscle cells. In the present study, we found that dapagliflozin has a significant vasodilatory effect on rat coronary arteries. Our findings suggest a novel pharmacologic approach for the treatment of cardiovascular diseases in diabetic patients through the modulation of Ca2+ homeostasis via dapagliflozin administration.
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Vasos Coronários , Vasodilatação , Humanos , Ratos , Masculino , Animais , Ratos Sprague-Dawley , Trifosfato de Adenosina/farmacologia , Endotélio Vascular , Vasodilatadores/farmacologiaRESUMO
Virtual reality technology has been adopted to overcome barriers of conventional simulation. This study was conducted to determine the impact of mixed simulation (a 360° virtual reality and a high-fidelity simulator) on learning how to provide nursing care for patients with arrhythmia. A total of 49 students were randomly assigned to intervention (n = 25) and control (n = 23) groups. They were given four arrhythmia cases with a 360° virtual reality system first followed by a manikin-based simulation. The mixed simulation group showed greater improvement in knowledge, higher decision-making competency in "knowing and acting" ( P = .025) and "seeking information from instructors" ( P = .049), and lower anxiety in "using resources to gather information" ( P = .031). Study participants achieved a good level of empathy (3.28 ± 0.72) and liked the program (4.56 ± 0.60). They were satisfied with the program (4.48 ± 0.65). These findings provide new insight into learning through blending of new technology. When the 360° virtual reality was used with existing manikin-based simulation, they effectively reinforced one another. The 360° virtual reality can be an effective strategy to ensure active participation to gain a comprehensive understanding of and empathy for patients.
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Treinamento por Simulação , Realidade Virtual , Humanos , Competência Clínica , Simulação por Computador , Estudos de Viabilidade , AprendizagemRESUMO
Background and Objectives: Currently, only patients with osteonecrosis of the femoral head (ONFH), who had bone defects involving 30-33.3% of the remaining femoral head, are indicated in hip resurfacing arthroplasty (HRA). In an experimental cadaver model of ONFH involving up to 50% of the remaining femoral head, the initial stability of the femoral head implant (FHI) at the interface between the implant and the remaining femoral head was measured. Materials and Methods: The ten specimens and the remaining ten served as the experimental group and the control group, respectively. We examined the degree of the displacement of the FHI, the bonding strength between the FHI and the retained bone and that at the interface between the FHI and bone cement. Results: Changes in the degree of displacement at the final phase from the initial phase were calculated as 0.089 ± 0.036 mm in the experimental group and 0.083 ± 0.056 mm in the control group. However, this difference reached no statistical significance (p = 0.7789). Overall, there was an increase in the degree of displacement due to the loading stress, with increased loading cycles in both groups. In cycles of up to 6000 times, there was a steep increase. After cycles of 8000 times, however, there was a gradual increase. Moreover, in cycles of up to 8000 times, there was an increase in the difference in the degree of displacement due to the loading stress between the two groups. After cycles of 8000 times, however, such difference remained almost unchanged. Conclusions: In conclusion, orthopedic surgeons could consider performing the HRA in patients with ONFH where the bone defects involved up to 50% of the remaining femoral head, without involving the femoral head-neck junction in the anterior and superior area of the femoral head. However, more evidence-based studies are warranted to justify our results.
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Artroplastia de Quadril , Necrose da Cabeça do Fêmur , Humanos , Cabeça do Fêmur/cirurgia , Necrose da Cabeça do Fêmur/cirurgia , Fêmur , Colo do Fêmur , Artroplastia de Quadril/efeitos adversos , CadáverRESUMO
PURPOSE: The treatment of irreducible or severely displaced metacarpal and phalangeal bone fractures is still much debated. The recent development of the bioabsorbable magnesium K-wire is thought to allow effective treatment upon insertion via intramedullary fixation by minimizing articular cartilage injuries without discomfort until pin removal and drawbacks, such as pin track infection and metal plate removal. Therefore, this study investigated and reported the effects of intramedullary fixation with the bioabsorbable magnesium K-wire in unstable metacarpal and phalangeal bone fractures. METHODS: This study included 19 patients admitted to our clinic for metacarpal or phalangeal bone fractures from May 2019 to July 2021. As a result, 20 cases were examined among these 19 patients. RESULTS: Bone union was observed in all 20 cases, with a mean bone union time of 10.5 (SD 3.4) weeks. Reduction loss was observed in six cases, all showing dorsal angulation with a mean angle of 6.6° (SD 3.5°) at 4.6 weeks as compared with that noted in the unaffected side. The gas cavity upon H2 gas formation was first observed approximately 2 weeks postoperatively. The mean DASH score was 33.5 for instrumental activity and 9.5 for work/task performance. No patient complained of notable discomfort after surgery. CONCLUSION: Intramedullary fixation with the bioabsorbable magnesium K-wire may be used for unstable metacarpal and phalanx bone fractures. This wire is expected to be a particularly favorable indication for shaft fractures, although care should be taken due to the possibility of complications related to rigidity and deformity.
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Fixação Intramedular de Fraturas , Fraturas Ósseas , Ossos Metacarpais , Humanos , Ossos Metacarpais/cirurgia , Ossos Metacarpais/lesões , Implantes Absorvíveis , Magnésio , Fixação Intramedular de Fraturas/efeitos adversos , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Fios Ortopédicos , Fixação Interna de Fraturas/efeitos adversosRESUMO
Heme oxygenase (HO) converts heme to carbon monoxide, biliverdin, and free iron, products that are essential in cellular redox signaling and iron recycling. In higher plants, HO is also involved in the biosynthesis of photoreceptor pigment precursors. Despite many common enzymatic reactions, the amino acid sequence identity between plant-type and other HOs is exceptionally low (â¼19.5%), and amino acids that are catalytically important in mammalian HO are not conserved in plant-type HOs. Structural characterization of plant-type HO is limited to spectroscopic characterization by electron spin resonance, and it remains unclear how the structure of plant-type HO differs from that of other HOs. Here, we have solved the crystal structure of Glycine max (soybean) HO-1 (GmHO-1) at a resolution of 1.06 Å and carried out the isothermal titration calorimetry measurements and NMR spectroscopic studies of its interaction with ferredoxin, the plant-specific electron donor. The high-resolution X-ray structure of GmHO-1 reveals several novel structural components: an additional irregularly structured region, a new water tunnel from the active site to the surface, and a hydrogen-bonding network unique to plant-type HOs. Structurally important features in other HOs, such as His ligation to the bound heme, are conserved in GmHO-1. Based on combined data from X-ray crystallography, isothermal titration calorimetry, and NMR measurements, we propose the evolutionary fine-tuning of plant-type HOs for ferredoxin dependency in order to allow adaptation to dynamic pH changes on the stroma side of the thylakoid membrane in chloroplast without losing enzymatic activity under conditions of fluctuating light.
Assuntos
Ferredoxinas/química , Glycine max/química , Heme Oxigenase-1/química , Heme/química , Ferro/química , Proteínas de Plantas/química , Sequência de Aminoácidos , Biliverdina/química , Biliverdina/metabolismo , Monóxido de Carbono/química , Monóxido de Carbono/metabolismo , Domínio Catalítico , Cloroplastos/química , Cloroplastos/enzimologia , Clonagem Molecular , Cristalografia por Raios X , Escherichia coli/genética , Escherichia coli/metabolismo , Ferredoxinas/genética , Ferredoxinas/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Heme/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Ligação de Hidrogênio , Ferro/metabolismo , Simulação de Acoplamento Molecular , Ressonância Magnética Nuclear Biomolecular , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Glycine max/enzimologia , Glycine max/genética , Tilacoides/química , Tilacoides/enzimologiaRESUMO
NMR is a powerful tool for characterizing intermolecular interactions at atomic resolution. However, the nature of the complex interactions of membrane-binding proteins makes it difficult to elucidate the interaction mechanisms. Here, we demonstrated that structural and thermodynamic analyses using solution NMR spectroscopy and isothermal titration calorimetry (ITC) can clearly detect a specific interaction between the pleckstrin homology (PH) domain of ceramide transport protein (CERT) and phosphatidylinositol 4-monophosphate (PI4P) embedded in the lipid nanodisc, and distinguish the specific interaction from nonspecific interactions with the bulk surface of the lipid nanodisc. This NMR-ITC hybrid strategy provides detailed characterization of protein-lipid membrane interactions.
Assuntos
Bicamadas Lipídicas/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Fosfatos de Fosfatidilinositol/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Calorimetria/instrumentação , Calorimetria/métodos , Humanos , Bicamadas Lipídicas/química , Espectroscopia de Ressonância Magnética/instrumentação , Simulação de Dinâmica Molecular , Nanoestruturas/química , Fosfatos de Fosfatidilinositol/química , Ligação Proteica , Domínios Proteicos , Proteínas Serina-Treonina Quinases/química , Titulometria/instrumentação , Titulometria/métodosRESUMO
As a central feature of neuroinflammation, microglial dysfunction has been increasingly considered a causative factor of neurodegeneration implicating an intertwined pathology with amyloidogenic proteins. Herein, we report the smallest synthetic molecule (N,N'-diacetyl-p-phenylenediamine [DAPPD]), simply composed of a benzene ring with 2 acetamide groups at the para position, known to date as a chemical reagent that is able to promote the phagocytic aptitude of microglia and subsequently ameliorate cognitive defects. Based on our mechanistic investigations in vitro and in vivo, 1) the capability of DAPPD to restore microglial phagocytosis is responsible for diminishing the accumulation of amyloid-ß (Aß) species and significantly improving cognitive function in the brains of 2 types of Alzheimer's disease (AD) transgenic mice, and 2) the rectification of microglial function by DAPPD is a result of its ability to suppress the expression of NLRP3 inflammasome-associated proteins through its impact on the NF-κB pathway. Overall, our in vitro and in vivo investigations on efficacies and molecular-level mechanisms demonstrate the ability of DAPPD to regulate microglial function, suppress neuroinflammation, foster cerebral Aß clearance, and attenuate cognitive deficits in AD transgenic mouse models. Discovery of such antineuroinflammatory compounds signifies the potential in discovering effective therapeutic molecules against AD-associated neurodegeneration.
Assuntos
Doença de Alzheimer/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Cognição/efeitos dos fármacos , Microglia/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Fagocitose/efeitos dos fármacos , Fenilenodiaminas/farmacologia , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Anti-Inflamatórios/uso terapêutico , Avaliação Pré-Clínica de Medicamentos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamassomos/efeitos dos fármacos , Inflamassomos/genética , Aprendizagem em Labirinto , Camundongos , Camundongos Transgênicos , Microglia/fisiologia , Estrutura Molecular , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Fármacos Neuroprotetores/uso terapêutico , Fragmentos de Peptídeos/genética , Fenilenodiaminas/química , Fenilenodiaminas/uso terapêutico , Presenilina-1/genética , Memória Espacial/efeitos dos fármacosRESUMO
While the neuropathological characteristics of Niemann-Pick disease type C (NPC) result in a fatal diagnosis, the development of clinically available therapeutic agent remains a challenge. Here we propose graphene quantum dots (GQDs) as a potential candidate for the impaired functions in NPC in vivo. In addition to the previous findings that GQDs exhibit negligible long-term toxicity and are capable of penetrating the blood-brain barrier, GQD treatment reduces the aggregation of cholesterol in the lysosome through expressed physical interactions. GQDs also promote autophagy and restore defective autophagic flux, which, in turn, decreases the atypical accumulation of autophagic vacuoles. More importantly, the injection of GQDs inhibits the loss of Purkinje cells in the cerebellum while also demonstrating reduced activation of microglia. The ability of GQDs to alleviate impaired functions in NPC proves the promise and potential of the use of GQDs toward resolving NPC and other related disorders.