Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 99
Filtrar
1.
Nano Lett ; 24(6): 1916-1922, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38215312

RESUMO

Electrochemistry has extended from reactions at solid/liquid interfaces to those at solid/solid interfaces. However, photoelectrochemistry at solid/solid interfaces has been hardly reported. In this study, we achieve a stable photoelectrochemical reaction at the semiconductor-electrode/solid-electrolyte interface in a Nb-doped anatase-TiO2 (a-TiO2:Nb)/Li3PO4 (LPO)/Li all-solid-state cell. The oxidative currents of a-TiO2:Nb/LPO/Li increase upon light irradiation when a-TiO2:Nb is located at a potential that is more positive than its flat-band potential. This is because the photoexcited electrons migrate to the current collector due to the bending of the conduction band minimum toward the negative potential. The photoelectrochemical reaction at the semiconductor/solid-electrolyte interface is driven by the same principle as those at semiconductor/liquid-electrolyte interfaces. Moreover, oxidation under light irradiation exhibits reversibility with reduction in the dark. Thus, we extend photoelectrochemistry to all-solid-state systems composed of solid/solid interfaces. This extension would enable us to investigate photoelectrochemical phenomena uncleared at solid/liquid interfaces because of low stability and durability.

2.
Exp Brain Res ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963561

RESUMO

In the flanker task, the behavioral performance for incompatible stimuli is worse in the mostly compatible (rare) condition than in the equiprobable condition. Furthermore, incompatible stimuli evoke visual mismatch negativity (VMMN) when comparing the rare and equiprobable conditions. Compatible and incompatible stimuli differ in terms of their shape and type. This study aimed to examine whether VMMN evoked by rare incompatible stimuli were associated with the shape or type of the stimulus. In a modified version of the flanker task, stimuli were manipulated by two shapes (typical or peculiar) and two types (compatible or incompatible): typical compatible stimuli (< < < < < and > > > > >), typical incompatible stimuli (> > < > > and < < > < <), peculiar compatible stimuli (+ < < < + and + > > > +), and peculiar incompatible stimuli (+ > < > + and + < > < +). In the rare condition, typical incompatible, peculiar compatible, and peculiar incompatible stimuli were presented with a probability of 10%, whereas all the stimuli were presented equally in the equiprobable condition. Right posterior negativity from 200 to 250 ms was significantly more negative in the rare condition than in the equiprobable condition for typical and peculiar incompatible stimuli; however, this difference was not observed for peculiar compatible stimuli. VMMN was significantly more negative for typical and peculiar incompatible stimuli than for peculiar compatible stimuli, and was not significantly different between typical and peculiar incompatible stimuli. These findings suggest that VMMN for incompatible stimuli is associated with the type rather than the shape of the stimulus.

3.
J Artif Organs ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38594483

RESUMO

Since 2011, implantable ventricular assist devices have been a standard treatment for severe heart failure alongside heart transplantation in Japan. However, the limited availability of donors has led to a prolonged wait for transplants, now averaging 1719 days, intensifying the issue of aortic insufficiency in patients with continuous flow ventricular assist devices. These devices limit the opening of the aortic valve, leading to sustained closure and increased shear stress, which accelerates valve degradation. Risk factors for aortic insufficiency include having a smaller body surface area, being of advanced age, and the presence of mild aortic insufficiency prior to device implantation. In patients presenting with mild or moderate aortic regurgitation at the time of ventricular assist device implantation, interventions such as aortic valve repair or bioprosthetic valve replacement are performed with the aim of halting its progression. The choice of surgical procedure should be tailored to each patient's individual condition. The management of de novo aortic insufficiency in patients with continuous flow ventricular assist devices remains challenging, with no clear consensus on when to intervene. Interventions for significant aortic insufficiency typically consider the patient's symptoms and aortic insufficiency severity. De novo aortic insufficiency progression in continuous flow ventricular assist devices patients necessitates careful monitoring and intervention based on individual patient assessments and valve condition. This review was created based on a translation of the Japanese review written in the Japanese Journal of Artificial Organs in 2023 (Vol. 52, No. 1, pp. 77-80), with some modifications.

4.
J Anesth ; 38(1): 19-28, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37945905

RESUMO

BACKGROUND: Among assisted reproductive technologies, frozen thawed embryo transfer (FET) is associated with increased blood loss at delivery. Anesthesiologists need to be aware of new factors that affect postpartum blood loss. This study investigated whether FET cycles with or without hormonal support affect the amount of postpartum bleeding. METHODS: We conducted a retrospective cohort study of patients admitted for delivery at a single university hospital between January 2015 and December 2018. Patients were divided into no-assisted reproductive technology (No-ART), hormonal cycle FET (HC-FET) and natural cycle FET (NC-FET) group. The primary outcome was the amount of blood loss after delivery (median [interquartile range]), which was compared among the three groups. Multiple regression analysis was performed to investigate the factors affecting blood loss. RESULTS: Between 2015 and 2018, 3187 women delivered neonates. In vaginal delivery, postpartum blood loss in the HC-FET group (1060 [830] g) was significantly greater than in the NC-FET group (650 [485] g, P = 0.001) and in the No-ART group (590 [420] g P < 0.001). Multiple linear regression analysis showed that HC-FET (P < 0.001) was one of the independent factors for the amount of bleeding. In cesarean delivery, the HC-FET group had more blood loss than the No-ART group (910 [676] g vs. 784 [524] g, P = 0.039). However, HC-FET was not an independent factor for postpartum blood loss. CONCLUSIONS: The HC-FET group had more blood loss than the No-ART group for both vaginal and cesarean deliveries. Furthermore, HC-FET was an independent factor that increased postpartum blood loss in vaginal deliveries.


Assuntos
Hemorragia Pós-Parto , Técnicas de Reprodução Assistida , Gravidez , Recém-Nascido , Feminino , Humanos , Estudos Retrospectivos , Transferência Embrionária , Período Pós-Parto
5.
J Am Chem Soc ; 144(1): 236-247, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34957828

RESUMO

Li2MnO3 is a promising cathode candidate for Li-ion batteries because of its high discharge capacity; however, its reaction mechanism during cycling has not been sufficiently explicated. Observations of Mn and O binding energy shifts in operando hard X-ray photoelectron spectroscopy measurements enabled us to determine the charge-compensation mechanism of Li2MnO3. The O 1s peak splits at an early stage during the first charge, and the concentration of lower-valence O changes reversibly with cycling, indicating the formation of a low-valence O species that intrinsically participates in the redox reaction. The O 1s peak-splitting behavior, which indicates the number of valences of O in Li2MnO3, is supported by the computational results for an O3 to O1 structural transition. This is in agreement with the results of our previous study, wherein we confirmed this O3 to O1 transition based on in situ surface X-ray diffraction analysis, X-ray photoelectron spectroscopy, and first-principles formation energy calculations.

6.
J Am Chem Soc ; 144(11): 4989-4994, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35138083

RESUMO

Solid-state electrolytes that exhibit high ionic conductivities at room temperature are key materials for obtaining the next generation of safer, higher-specific-energy solid-state batteries. However, the number of currently available crystal structures for use as superionic conductors remains limited. Here, we report a lithium superionic conductor, Li2SiS3, with tetragonal crystal symmetry, which possesses a new three-dimensional framework structure consisting of isolated edge-sharing tetrahedral dimers. This species exhibits an anomalously high ionic conductivity of 2.4 mS cm-1 at 298 K, which is 3 orders of magnitude higher than the reported ionic conductivity for its orthorhombic polymorph. The framework of this conductor consists mainly of silicon, which is abundant in natural resources, and its further optimization may lead to the development of new solid-state electrolytes for large-scale applications.

7.
Inorg Chem ; 61(1): 52-61, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34914367

RESUMO

Understanding the fast Li ionic conductors of oxygen-substituted thiophosphates is useful for developing all-solid-state batteries because these compounds possess a high electrochemical stability and thus may be applied as solid electrolytes. In this study, we synthesized the Li9+δP3+δ'S12-kOk series of solid solution phases with the same structure as the Li10GeP2S12 superionic conductor and characterized their crystallinity, solid solution range, and chemical stabilities. Two methods (mechanochemical and melt quenching) were used for sample synthesis. Mechanochemical synthesis was used to obtain samples within a wide range of sulfur/oxygen substitution degrees, and the solid solution range was determined to be 0 < k ≤ 3.6 based on their lattice parameter variation. Meanwhile, the melt-quenched Li9P3S9O3 phase exhibited a high degree of crystallinity up to its particle surface and was thus selected for neutron crystal structure analysis, which revealed the oxygen distribution related to the solubility limit. The highly crystalline melt-quenched Li9P3S9O3 showed better stability in the air atmosphere compared to the mechanochemically synthesized counterpart with a low crystallinity, implying that sample crystallinity is an important parameter in evaluating the air stability of thiophosphates. The promising electrochemical properties of the solid solution series were demonstrated by the stable charge-discharge cycling of an all-solid-state lithium metal cell using the Li9+δP3+δ'S12-kOk electrolyte with k = 0.9 and a conductivity of >1 × 10-3 S cm-1 at 300 K.

8.
Cardiol Young ; 32(11): 1845-1847, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35225203

RESUMO

We report the first successful Glenn procedure for pulmonary atresia with intact ventricular septum in the setting of D-transposition of the great arteries. This case was complicated by hypoplastic left ventricle and severe mitral regurgitation. Partial closure of the mitral valve at the time of Blalock-Taussig shunting resulted in improvement of heart failure.


Assuntos
Insuficiência da Valva Mitral , Atresia Pulmonar , Transposição dos Grandes Vasos , Humanos , Transposição dos Grandes Vasos/complicações , Transposição dos Grandes Vasos/cirurgia , Ventrículos do Coração/anormalidades , Insuficiência da Valva Mitral/diagnóstico , Insuficiência da Valva Mitral/etiologia , Insuficiência da Valva Mitral/cirurgia , Atresia Pulmonar/cirurgia , Artérias
9.
Proc Natl Acad Sci U S A ; 115(30): E7129-E7138, 2018 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-29987023

RESUMO

Although postcapillary pulmonary hypertension (PH) is an important prognostic factor for patients with heart failure (HF), its pathogenesis remains to be fully elucidated. To elucidate the different roles of Rho-kinase isoforms, ROCK1 and ROCK2, in cardiomyocytes in response to chronic pressure overload, we performed transverse aortic constriction (TAC) in cardiac-specific ROCK1-deficient (cROCK1-/-) and ROCK2-deficient (cROCK2-/-) mice. Cardiomyocyte-specific ROCK1 deficiency promoted pressure-overload-induced cardiac dysfunction and postcapillary PH, whereas cardiomyocyte-specific ROCK2 deficiency showed opposite results. Histological analysis showed that pressure-overload-induced cardiac hypertrophy and fibrosis were enhanced in cROCK1-/- mice compared with controls, whereas cardiac hypertrophy was attenuated in cROCK2-/- mice after TAC. Consistently, the levels of oxidative stress were up-regulated in cROCK1-/- hearts and down-regulated in cROCK2-/- hearts compared with controls after TAC. Furthermore, cyclophilin A (CyPA) and basigin (Bsg), both of which augment oxidative stress, enhanced cardiac dysfunction and postcapillary PH in cROCK1-/- mice, whereas their expressions were significantly lower in cROCK2-/- mice. In clinical studies, plasma levels of CyPA were significantly increased in HF patients and were higher in patients with postcapillary PH compared with those without it. Finally, high-throughput screening demonstrated that celastrol, an antioxidant and antiinflammatory agent, reduced the expressions of CyPA and Bsg in the heart and the lung, ameliorating cardiac dysfunction and postcapillary PH induced by TAC. Thus, by differentially affecting CyPA and Bsg expressions, ROCK1 protects and ROCK2 jeopardizes the heart from pressure-overload HF with postcapillary PH, for which celastrol may be a promising agent.


Assuntos
Cardiomegalia/metabolismo , Insuficiência Cardíaca/metabolismo , Hipertensão Pulmonar/metabolismo , Pulmão/metabolismo , Miocárdio/metabolismo , Quinases Associadas a rho/metabolismo , Animais , Basigina/biossíntese , Basigina/genética , Cardiomegalia/genética , Cardiomegalia/patologia , Ciclofilina A/biossíntese , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/patologia , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/patologia , Pulmão/patologia , Camundongos , Camundongos Knockout , Miocárdio/patologia , Quinases Associadas a rho/genética
10.
Dev Psychobiol ; 63(3): 452-460, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32945540

RESUMO

Brain monoaminergic neurotransmitters, such as dopamine (DA), serotonin (5-HT), and noradrenaline (NA), play crucial roles in neuronal and physiological functions, including social behaviors. Isolation housing may induce behavioral and neurochemical abnormalities in rats, although its influence on neurotransmitter levels remains obscure. This study investigated the influence of isolation- or group-housing on core body temperature (Tcore ), locomotor activity (ACT), emotional behavior, and neurotransmitter levels in male Wistar rats. Behavioral changes were monitored using the open field test (OFT) and social interaction test (SIT). After 4 weeks, brain tissues were collected to quantify 5-HT, DA, and NA concentrations. Body weight and basal Tcore during both the light and dark phase were higher in isolation-housed than in group-housed rats, although no significant difference was seen in ACT. No significant differences were observed during the OFT. Isolation-housed rats showed increased line crossing and decreased social behavior during the SIT. Isolation-housed rats exhibited decreased levels of 5-HT in the caudate putamen and amygdala, and elevated and decreased NA levels in the paraventricular hypothalamic nucleus and hippocampus, respectively. However, DA levels were unaffected. Thus, housing environments may affect brain areas that regulate various neuronal and physiological functions, such as memory, stress responses, and emotional behavior.


Assuntos
Neurotransmissores , Serotonina , Animais , Dopamina , Masculino , Norepinefrina , Ratos , Ratos Wistar
11.
Molecules ; 26(2)2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33435543

RESUMO

Perovskite-type lithium ionic conductors were explored in the (LixLa1-x/3)ScO3 system following their syntheses via a high-pressure solid-state reaction. Phase identification indicated that a solid solution with a perovskite-type structure was formed in the range 0 ≤ x < 0.6. When x = 0.45, (Li0.45La0.85)ScO3 exhibited the highest ionic conductivity and a low activation energy. Increasing the loading of lithium as an ionic diffusion carrier expanded the unit cell volume and contributed to the higher ionic conductivity and lower activation energy. Cations with higher oxidation numbers were introduced into the A/B sites to improve the ionic conductivity. Ce4+ and Zr4+ or Nb5+ dopants partially substituted the A-site (La/Li) and B-site Sc, respectively. Although B-site doping produced a lower ionic conductivity, A-site Ce4+ doping improved the conductive properties. A perovskite-type single phase was obtained for (Li0.45La0.78Ce0.05)ScO3 upon Ce4+ doping, providing a higher ionic conductivity than (Li0.45La0.85)ScO3. Compositional analysis and crystal-structure refinement of (Li0.45La0.85)ScO3 and (Li0.45La0.78Ce0.05)ScO3 revealed increased lithium contents and expansion of the unit cell upon Ce4+ co-doping. The highest ionic conductivity of 1.1 × 10-3 S cm-1 at 623 K was confirmed for (Li0.4Ce0.15La0.67)ScO3, which is more than one order of magnitude higher than that of the (LixLa1-x/3)ScO3 system.


Assuntos
Compostos de Cálcio/química , Eletrodos , Eletrônica/instrumentação , Lantânio/química , Lítio/química , Óxidos/química , Escândio/química , Titânio/química , Condutividade Elétrica
12.
Arterioscler Thromb Vasc Biol ; 39(5): 934-944, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30866657

RESUMO

Objective- Secondary prevention for recurrent myocardial infarction (MI) is one of the most important therapeutic goals in patients with old MI (OMI). Although statins are widely used for this purpose, there remains considerable residual risk even after LDL (low-density lipoprotein cholesterol) is well controlled by statins. Approach and Results- We examined clinical impacts of nHDL (nonhigh-density lipoprotein cholesterol) and its major components triglyceride and LDL as residual risks for acute MI recurrence, using the database of our CHART (Chronic Heart Failure Analysis and Registry in the Tohoku District)-2 Study, the largest-scale cohort study of cardiovascular patients in Japan. We enrolled 1843 consecutive old MI patients treated with statins (mean age 67.3 years, male 19.2%) in the CHART-2 Study. The incidence of recurrent acute MI during the median 8.6-year follow-up was compared among the groups divided by the levels of nHDL (<100, 100-129, and ≥130 mg/dL), LDL (<70, 70-99, and ≥100 mg/dL), triglyceride (<84, 84-149, and ≥150 mg/dL), and combination of LDL and triglyceride. Kaplan-Meier curves and multiple Cox proportional hazards models showed that higher levels of nHDL, but not LDL or triglyceride alone, were associated with higher incidence of recurrent acute MI. Furthermore, higher triglyceride levels were associated with higher incidence of recurrent MI in patients with LDL <100 mg/dL but not in those with LDL ≥100 mg/dL. Conclusions- These results indicate that management of residual risks for acute MI recurrence should include nHDL management considering both LDL and triglyceride in old MI patients under statin treatment. Clinical Trial Registration- URL: http://www.clinicaltrials.gov . Unique identifier: NCT00418041.


Assuntos
LDL-Colesterol/sangue , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Infarto do Miocárdio/sangue , Infarto do Miocárdio/mortalidade , Prevenção Secundária/métodos , Triglicerídeos/sangue , Idoso , Biomarcadores/sangue , HDL-Colesterol/sangue , Estudos de Coortes , Feminino , Humanos , Japão , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/tratamento farmacológico , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Recidiva , Medição de Risco , Índice de Gravidade de Doença , Análise de Sobrevida
13.
Circ J ; 84(6): 926-934, 2020 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-32295976

RESUMO

BACKGROUND: Infective endocarditis remains associated with substantial mortality and morbidity rates, and the presence of acute heart failure (AHF) compromises clinical results after valve surgery; however, little is known in cardiogenic shock (CGS) patients. This study evaluated the clinical results and risk of mortality in CGS patients after valve surgery.Methods and Results:This study enrolled 585 patients who underwent valve surgery for active endocarditis at 14 institutions between 2009 and 2017. Of these patients, 69 (12%) were in CGS, which was defined as systolic blood pressure <80 mmHg and severe pulmonary congestion, requiring mechanical ventilation and/or mechanical circulatory support, preoperatively. The predictors of CGS were analyzed, and clinical results of patients with non-CGS AHF (n=215) were evaluated and compared.Staphylococcus aureusinfection (odds ratio [OR] 2.19; P=0.044), double valve involvement (OR 3.37; P=0.003), and larger vegetation (OR 1.05; P=0.036) were risk factors for CGS. Hospital mortality occurred in 27 (13%) non-CGS AHF patients and in 15 (22%) CGS patients (P=0.079). Overall survival at 1 and 5 years in CGS patients was 76% and 69%, respectively, and there were no significant differences in overall survival compared with non-CGS AHF patients (P=1.000). CONCLUSIONS: Clinical results after valve surgery in CGS patients remain challenging; however, mid-term results were equivalent to those of non-CGS AHF patients.


Assuntos
Circulação Assistida , Endocardite Bacteriana/cirurgia , Oxigenação por Membrana Extracorpórea , Implante de Prótese de Valva Cardíaca , Choque Cardiogênico/terapia , Idoso , Circulação Assistida/efeitos adversos , Circulação Assistida/mortalidade , Bases de Dados Factuais , Endocardite Bacteriana/diagnóstico , Endocardite Bacteriana/mortalidade , Endocardite Bacteriana/fisiopatologia , Oxigenação por Membrana Extracorpórea/efeitos adversos , Oxigenação por Membrana Extracorpórea/mortalidade , Feminino , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/mortalidade , Mortalidade Hospitalar , Humanos , Balão Intra-Aórtico , Japão , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Estudos Retrospectivos , Fatores de Risco , Choque Cardiogênico/diagnóstico , Choque Cardiogênico/mortalidade , Choque Cardiogênico/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
14.
Circ Res ; 120(8): 1246-1262, 2017 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-28289017

RESUMO

RATIONALE: Pulmonary hypertension is a fatal disease; however, its pathogenesis still remains to be elucidated. Thrombin-activatable fibrinolysis inhibitor (TAFI) is synthesized by the liver and inhibits fibrinolysis. Plasma TAFI levels are significantly increased in chronic thromboembolic pulmonary hypertension (CTEPH) patients. OBJECTIVE: To determine the role of activated TAFI (TAFIa) in the development of CTEPH. METHODS AND RESULTS: Immunostaining showed that TAFI and its binding partner thrombomodulin (TM) were highly expressed in the pulmonary arteries (PAs) and thrombus in patients with CTEPH. Moreover, plasma levels of TAFIa were increased 10-fold in CTEPH patients compared with controls. In mice, chronic hypoxia caused a 25-fold increase in plasma levels of TAFIa with increased plasma levels of thrombin and TM, which led to thrombus formation in PA, vascular remodeling, and pulmonary hypertension. Consistently, plasma clot lysis time was positively correlated with plasma TAFIa levels in mice. Additionally, overexpression of TAFIa caused organized thrombus with multiple obstruction of PA flow and reduced survival rate under hypoxia in mice. Bone marrow transplantation showed that circulating plasma TAFI from the liver, not in the bone marrow, was activated locally in PA endothelial cells through interactions with thrombin and TM. Mechanistic experiments demonstrated that TAFIa increased PA endothelial permeability, smooth muscle cell proliferation, and monocyte/macrophage activation. Importantly, TAFIa inhibitor and peroxisome proliferator-activated receptor-α agonists significantly reduced TAFIa and ameliorated animal models of pulmonary hypertension in mice and rats. CONCLUSIONS: These results indicate that TAFIa could be a novel biomarker and realistic therapeutic target of CTEPH.


Assuntos
Pressão Arterial , Carboxipeptidase B2/metabolismo , Hipertensão Pulmonar/etiologia , Fígado/metabolismo , Artéria Pulmonar/metabolismo , Tromboembolia/complicações , Adulto , Animais , Permeabilidade Capilar , Carboxipeptidase B2/deficiência , Carboxipeptidase B2/genética , Estudos de Casos e Controles , Proliferação de Células , Doença Crônica , Modelos Animais de Doenças , Feminino , Células Hep G2 , Humanos , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/prevenção & controle , Hipóxia/complicações , Fígado/efeitos dos fármacos , Ativação de Macrófagos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Músculo Liso Vascular/fisiopatologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , PPAR alfa/agonistas , PPAR alfa/metabolismo , Artéria Pulmonar/patologia , Artéria Pulmonar/fisiopatologia , Pirimidinas/farmacologia , Ratos Sprague-Dawley , Transdução de Sinais , Trombina/metabolismo , Tromboembolia/metabolismo , Tromboembolia/fisiopatologia , Tromboembolia/prevenção & controle , Trombomodulina/metabolismo , Transfecção , Regulação para Cima
15.
Circ Res ; 119(2): 197-209, 2016 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-27217398

RESUMO

RATIONALE: Endothelial AMP-activated protein kinase (AMPK) plays an important role for vascular homeostasis, and its role is impaired by vascular inflammation. However, the role of endothelial AMPK in the pathogenesis of pulmonary arterial hypertension (PAH) remains to be elucidated. OBJECTIVE: To determine the role of endothelial AMPK in the development of PAH. METHODS AND RESULTS: Immunostaining showed that endothelial AMPK is downregulated in the pulmonary arteries of patients with PAH and hypoxia mouse model of pulmonary hypertension (PH). To elucidate the role of endothelial AMPK in PH, we used endothelial-specific AMPK-knockout mice (eAMPK(-/-)), which were exposed to hypoxia. Under normoxic condition, eAMPK(-/-) mice showed the normal morphology of pulmonary arteries compared with littermate controls (eAMPK(flox/flox)). In contrast, development of hypoxia-induced PH was accelerated in eAMPK(-/-) mice compared with controls. Furthermore, the exacerbation of PH in eAMPK(-/-) mice was accompanied by reduced endothelial function, upregulation of growth factors, and increased proliferation of pulmonary artery smooth muscle cells. Importantly, conditioned medium from endothelial cells promoted pulmonary artery smooth muscle cell proliferation, which was further enhanced by the treatment with AMPK inhibitor. Serum levels of inflammatory cytokines, including tumor necrosis factor-α and interferon-γ were significantly increased in patients with PAH compared with healthy controls. Consistently, endothelial AMPK and cell proliferation were significantly reduced by the treatment with serum from patients with PAH compared with controls. Importantly, long-term treatment with metformin, an AMPK activator, significantly attenuated hypoxia-induced PH in mice. CONCLUSIONS: These results indicate that endothelial AMPK is a novel therapeutic target for the treatment of PAH.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Endotélio Vascular/enzimologia , Hipertensão Pulmonar/enzimologia , Hipertensão Pulmonar/prevenção & controle , Hipóxia/enzimologia , Hipóxia/prevenção & controle , Adulto , Idoso , Animais , Células Cultivadas , Ativação Enzimática/fisiologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade
16.
J Org Chem ; 83(22): 13965-13972, 2018 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-30362755

RESUMO

The AgOAc/ThioClickFerrophos complex catalyzed conjugate additions and 1,3-dipolar cycloadditions of 3-methyl-4-nitro-5-styrylisoxazoles with 1-pyrroline-5-carboxylates and glycine imino esters to give the corresponding Michael adducts and cycloadducts, respectively, in good yields with excellent diastereo- and enantioselectivities. These reactions can provide pyrroline- or pyrrolidine-containing isoxazole hybrid molecules that have potential biological and pharmaceutical activities.

17.
Arterioscler Thromb Vasc Biol ; 36(1): 97-107, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26543099

RESUMO

OBJECTIVE: Endothelium-derived nitric oxide (NO) and endothelium-dependent hyperpolarization (EDH) play important roles in modulating vascular tone in a distinct vessel size-dependent manner; NO plays a dominant role in conduit arteries and EDH in resistance vessels. We have recently demonstrated that endothelial NO synthase (eNOS) is functionally suppressed in resistance vessels through caveolin-1 (Cav-1)-dependent mechanism, switching its function from NO to EDH/hydrogen peroxide generation in mice. Here, we examined the possible importance of the physiological balance between NO and EDH in cardiovascular homeostasis. APPROACH AND RESULTS: We used 2 genotypes of mice in which eNOS activity is genetically upregulated; Cav-1-knockout (Cav-1-KO) and endothelium-specific eNOS transgenic (eNOS-Tg) mice. Isometric tension recordings and Langendorff experiments with isolated perfused hearts showed that NO-mediated relaxations were significantly enhanced, whereas EDH-mediated relaxations were markedly reduced in microcirculations. Importantly, impaired EDH-mediated relaxations of small mesenteric arteries from Cav-1-KO mice were completely rescued by crossing the mice with those with endothelium-specific overexpression of Cav-1. Furthermore, both genotypes showed altered cardiovascular phenotypes, including cardiac hypertrophy in Cav-1-KO mice and hypotension in eNOS-Tg mice. Finally, we examined cardiac responses to chronic pressure overload by transverse aortic constriction in vivo. When compared with wild-type mice, both Cav-1-KO and eNOS-Tg mice exhibited reduced survival after transverse aortic constriction associated with accelerated left ventricular systolic dysfunction, reduced coronary flow reserve, and enhanced myocardial hypoxia. CONCLUSIONS: These results indicate that excessive endothelium-derived NO with reduced EDH impairs cardiovascular homeostasis in mice in vivo.


Assuntos
Fatores Biológicos/metabolismo , Endotélio Vascular/enzimologia , Óxido Nítrico/metabolismo , Vasodilatação , Função Ventricular Esquerda , Animais , Cardiomegalia/enzimologia , Cardiomegalia/genética , Cardiomegalia/patologia , Caveolina 1/deficiência , Caveolina 1/genética , Hipóxia Celular , Circulação Coronária , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Inibidores Enzimáticos/farmacologia , Genótipo , Homeostase , Hipotensão/enzimologia , Hipotensão/genética , Hipotensão/fisiopatologia , Preparação de Coração Isolado , Masculino , Potenciais da Membrana , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microcirculação , Miocárdio/metabolismo , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Óxido Nítrico Sintase Tipo III/biossíntese , Óxido Nítrico Sintase Tipo III/genética , Fenótipo , Transdução de Sinais , Sístole , Fatores de Tempo , Regulação para Cima , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Disfunção Ventricular Esquerda/enzimologia , Disfunção Ventricular Esquerda/genética , Disfunção Ventricular Esquerda/fisiopatologia
18.
Arterioscler Thromb Vasc Biol ; 36(4): 636-46, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26916734

RESUMO

OBJECTIVE: Basigin (Bsg) is a transmembrane glycoprotein that activates matrix metalloproteinases and promotes inflammation. However, the role of Bsg in the pathogenesis of cardiac hypertrophy and failure remains to be elucidated. We examined the role of Bsg in cardiac hypertrophy and failure in mice and humans. APPROACH AND RESULTS: We performed transverse aortic constriction in Bsg(+/-) and in wild-type mice. Bsg(+/-) mice showed significantly less heart and lung weight and cardiac interstitial fibrosis compared with littermate controls after transverse aortic constriction. Both matrix metalloproteinase activities and oxidative stress in loaded left ventricle were significantly less in Bsg(+/-) mice compared with controls. Echocardiography showed that Bsg(+/-) mice showed less hypertrophy, less left ventricular dilatation, and preserved left ventricular fractional shortening compared with littermate controls after transverse aortic constriction. Consistently, Bsg(+/-) mice showed a significantly improved long-term survival after transverse aortic constriction compared with Bsg(+/+) mice, regardless of the source of bone marrow (Bsg(+/+) or Bsg(+/-)). Conversely, cardiac-specific Bsg-overexpressing mice showed significantly poor survival compared with littermate controls. Next, we isolated cardiac fibroblasts and examined their responses to angiotensin II or mechanical stretch. Both stimuli significantly increased Bsg expression, cytokines/chemokines secretion, and extracellular signal-regulated kinase/Akt/JNK activities in Bsg(+/+) cardiac fibroblasts, all of which were significantly less in Bsg(+/-) cardiac fibroblasts. Consistently, extracellular and intracellular Bsg significantly promoted cardiac fibroblast proliferation. Finally, serum levels of Bsg were significantly elevated in patients with heart failure and predicted poor prognosis. CONCLUSIONS: These results indicate the crucial roles of intracellular and extracellular Bsg in the pathogenesis of cardiac hypertrophy, fibrosis, and failure in mice and humans.


Assuntos
Doenças da Aorta/complicações , Basigina/metabolismo , Insuficiência Cardíaca/etiologia , Hipertrofia Ventricular Esquerda/etiologia , Miocárdio/metabolismo , Disfunção Ventricular Esquerda/etiologia , Angiotensina II/farmacologia , Animais , Animais Recém-Nascidos , Doenças da Aorta/genética , Doenças da Aorta/metabolismo , Doenças da Aorta/fisiopatologia , Basigina/genética , Proteínas Sanguíneas/metabolismo , Células Cultivadas , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibrose , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/prevenção & controle , Hipertrofia Ventricular Esquerda/genética , Hipertrofia Ventricular Esquerda/metabolismo , Hipertrofia Ventricular Esquerda/patologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Hipertrofia Ventricular Esquerda/prevenção & controle , Mediadores da Inflamação/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Masculino , Metaloproteinases da Matriz/metabolismo , Mecanotransdução Celular , Camundongos Knockout , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar , Fatores de Tempo , Disfunção Ventricular Esquerda/genética , Disfunção Ventricular Esquerda/metabolismo , Disfunção Ventricular Esquerda/patologia , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/prevenção & controle , Função Ventricular Esquerda
19.
Inorg Chem ; 56(4): 1846-1856, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28156109

RESUMO

Dinuclear and trinuclear ruthenium complexes, [Ru(trop)2(C2trop)Ru(dppe)Cp] [2b; trop = tropolonato, C2trop = ethynyltropolonato, dppe = 1,2-bis(diphenylphosphino)ethane] and [Ru(trop){(C2trop)Ru(dppe)Cp}2] (3), were synthesized, and their electronic and electrochemical properties were investigated in comparison with our previously reported complex [Ru(acac)2(C2trop)Ru(dppe)Cp] (2a). The electron-donating RuII(dppe)Cp unit and electron-accepting RuIIIO6 unit are connected by C2trop in these complexes. 2a incorporates acetylacetonate as an ancillary ligand, while 2b and 3 incorporate tropolonate as an ancillary ligand. Every complex, 2a, 2b, and 3, exhibits similar UV-vis-near-IR (NIR) absorption spectra, demonstrating the lack of explicit intramolecular electronic communication between the units at least in the neutral state. The weak NIR absorption in 2a further diminished upon electrochemical oxidation, indicating almost no electronic communication between the units. In contrast, 2b and 3 exhibit broad NIR absorptions upon oxidation. Additionally, 3 exhibits four stepwise redox couples in the electrochemical study, which are formally attributed to [RuII(trop)3]-/[RuIII(trop)3], two [RuII(dppe)Cp]/[RuIII(dppe)Cp]+, and [RuIII(trop)3]/[RuIV(trop)3]+ couples. Clear separation of the redox couples attributed to the two terminal [Ru(dppe)Cp] units demonstrates the thermodynamic stability of the intermediate oxidation states with respect to disproportionation. Further electrochemical studies using an electrolyte including perfluorinated weakly coordinating anions and density functional theory/time-dependent density functional theory calculations confirmed the effect of ancillary ligands, acetylacetonate and tropolonate. In the case of 2a, electronic delocalization over the whole complex, especially over the [Ru(acac)2(trop)] unit, appears to be small. In contrast, the electronic communication between [Ru(dppe)Cp] and [Ru(trop)3] units in 3 seems to be enhanced upon oxidation, resulting in the long-range intramolecular electronic communication.

20.
Circ Res ; 115(8): 738-50, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25149188

RESUMO

RATIONALE: Cyclophilin A (CyPA) is secreted from vascular smooth muscle cells (VSMCs) by oxidative stress and promotes VSMC proliferation. However, the role of extracellular CyPA and its receptor Basigin (Bsg, encoded by Bsg) in the pathogenesis of pulmonary hypertension (PH) remains to be elucidated. OBJECTIVE: To determine the role of CyPA/Bsg signaling in the development of PH. METHODS AND RESULTS: In the pulmonary arteries of patients with PH, immunostaining revealed strong expression of CyPA and Bsg. The pulmonary arteries of CyPA(±) and Bsg(±) mice exposed to normoxia did not differ in morphology compared with their littermate controls. In contrast, CyPA(±) and Bsg(±) mice exposed to hypoxia for 4 weeks revealed significantly reduced right ventricular systolic pressure, pulmonary artery remodeling, and right ventricular hypertrophy compared with their littermate controls. These features were unaltered by bone marrow reconstitution. To further evaluate the role of vascular Bsg, we harvested pulmonary VSMCs from Bsg(+/+) and Bsg(±) mice. Proliferation was significantly reduced in Bsg(±) compared with Bsg(+/+) VSMCs. Mechanistic studies demonstrated that Bsg(±) VSMCs revealed reduced extracellular signal-regulated kinase 1/2 activation and less secretion of cytokines/chemokines and growth factors (eg, platelet-derived growth factor-BB). Finally, in the clinical study, plasma CyPA levels in patients with PH were increased in accordance with the severity of pulmonary vascular resistance. Furthermore, event-free curve revealed that high plasma CyPA levels predicted poor outcome in patients with PH. CONCLUSIONS: These results indicate the crucial role of extracellular CyPA and vascular Bsg in the pathogenesis of PH.


Assuntos
Basigina/metabolismo , Hipertensão Pulmonar/metabolismo , Inflamação/metabolismo , Miócitos de Músculo Liso/metabolismo , Animais , Basigina/genética , Western Blotting , Hipóxia Celular , Proliferação de Células , Células Cultivadas , Quimiocinas/metabolismo , Ciclofilina A/sangue , Ciclofilina A/genética , Ciclofilina A/metabolismo , Citocinas/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Hipertensão Pulmonar/sangue , Hipertensão Pulmonar/genética , Hipóxia , Imuno-Histoquímica , Inflamação/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Knockout , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/patologia , Artéria Pulmonar/metabolismo , Artéria Pulmonar/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA