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1.
Medicine (Baltimore) ; 102(47): e36351, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38013260

RESUMO

The aim of this study was to investigate the clinical characteristics and prognosis of patients hospitalized with heart failure with preserved ejection fraction (HFpEF) and low N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels. Seven hundred ninety consecutive patients hospitalized with HFpEF from 2006 to 2017 were enrolled. Clinical characteristics and outcomes were compared between low NT-proBNP group (<300 ng/L) and elevated NT-proBNP group (≥300 ng/L). 108 HFpEF patients (13.7%) presented with low NT-proBNP levels. Age, body mass index, atrial fibrillation, New York Heart Association functional class, and albumin were independent predictors of low NT-proBNP levels in HFpEF patients. During the median follow-up duration of 1103 days, 11 patients (10.2%) in low NT-proBNP group suffered from primary endpoint event. Elevated NT-proBNP group had a higher risk of all-cause death or heart transplantation than low NT-proBNP group (adjusted HR [95%CI]: 2.36 [1.24,4.49], P = .009). Stratified analyses showed that the association between NT-proBNP (elevated NT-proBNP group vs low NT-proBNP group) and risk of all-cause death or heart transplantation was stronger in non-atrial fibrillation patients than in atrial fibrillation patients (P value for interaction = .025). Furthermore, the associations between NT-proBNP and risk of all-cause death or heart transplantation were stronger in younger and male patients than in older and female patients. However, both subgroups only reached borderline significant (P values for interaction = .062 and .084, respectively). Our findings suggest that low NT-proBNP levels were common in patients hospitalized with HFpEF. Patients with HFpEF and low NT-proBNP levels had a better prognosis than those with elevated NT-proBNP levels, particularly in younger, male, and non-atrial fibrillation patients.


Assuntos
Fibrilação Atrial , Insuficiência Cardíaca , Humanos , Masculino , Feminino , Idoso , Peptídeo Natriurético Encefálico , Volume Sistólico , Prognóstico , Fragmentos de Peptídeos , Biomarcadores
2.
Adv Sci (Weinh) ; 10(34): e2304329, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37870216

RESUMO

PIWI-interacting RNAs (piRNAs) are highly expressed in various cardiovascular diseases. However, their role in cardiomyocyte death caused by ischemia/reperfusion (I/R) injury, especially necroptosis, remains elusive. In this study, a heart necroptosis-associated piRNA (HNEAP) is found that regulates cardiomyocyte necroptosis by targeting DNA methyltransferase 1 (DNMT1)-mediated 5-methylcytosine (m5 C) methylation of the activating transcription factor 7 (Atf7) mRNA transcript. HNEAP expression level is significantly elevated in hypoxia/reoxygenation (H/R)-exposed cardiomyocytes and I/R-injured mouse hearts. Loss of HNEAP inhibited cardiomyocyte necroptosis and ameliorated cardiac function in mice. Mechanistically, HNEAP directly interacts with DNMT1 and attenuates m5 C methylation of the Atf7 mRNA transcript, which increases Atf7 expression level. ATF7 can further downregulate the transcription of Chmp2a, an inhibitor of necroptosis, resulting in the reduction of Chmp2a level and the progression of cardiomyocyte necroptosis. The findings reveal that piRNA-mediated m5 C methylation is involved in the regulation of cardiomyocyte necroptosis. Thus, the HNEAP-DNMT1-ATF7-CHMP2A axis may be a potential target for attenuating cardiac injury caused by necroptosis in ischemic heart disease.


Assuntos
Miócitos Cardíacos , Traumatismo por Reperfusão , Camundongos , Animais , Miócitos Cardíacos/metabolismo , RNA Mensageiro/metabolismo , RNA de Interação com Piwi , Necroptose/genética , Metilação , Traumatismo por Reperfusão/metabolismo , Fatores Ativadores da Transcrição/metabolismo
3.
J Biomed Sci ; 30(1): 45, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37370086

RESUMO

BACKGROUND: Emerging research has reported that circular RNAs (circRNAs) play important roles in cardiac cell death after myocardial ischemia and reperfusion (I/R). Ferroptosis, a new form of cell death discovered in recent years, has been proven to participate in the regulation of myocardial I/R. This study used circRNA sequencing to explore the key circRNA in the regulation of cardiac ferroptosis after I/R and study the mechanisms of potential circRNA function. METHODS: We performed circRNA sequencing to explore circRNAs differentially expressed after myocardial I/R. We used quantitative polymerase chain reactions to determine the circRNA expression in different tissues and detect the circRNA subcellular localization in the cardiomyocyte. Gain- and loss-of-function experiments were aimed to examine the function of circRNAs in cardiomyocyte ferroptosis and cardiac tissue damage after myocardial I/R. RNA pull-down was applied to explore proteins interacting with circRNA. RESULTS: Here, we identified a ferroptosis-associated circRNA (FEACR) that has an underlying regulatory role in cardiomyocyte ferroptosis. FEACR overexpression suppressed I/R-induced myocardial infarction and ameliorated cardiac function. FEACR inhibition induces ferroptosis in cardiomyocytes and FEACR overexpression inhibits hypoxia and reoxygenation-induced ferroptosis. Mechanistically, FEACR directly bound to nicotinamide phosphoribosyltransferase (NAMPT) and enhanced the protein stability of NAMPT, which increased NAMPT-dependent Sirtuin1 (Sirt1) expression, which promoted the transcriptional activity of forkhead box protein O1 (FOXO1) by reducing FOXO1 acetylation levels. FOXO1 further upregulated the transcription of ferritin heavy chain 1 (Fth1), a ferroptosis suppressor, which resulted in the inhibition of cardiomyocyte ferroptosis. CONCLUSIONS: Our finding reveals that the circRNA FEACR-mediated NAMPT-Sirt1-FOXO1-FTH1 signaling axis participates in the regulation of cardiomyocyte ferroptosis and protects the heart function against I/R injury. Thus, FEACR and its downstream factors could be novel targets for alleviating ferroptosis-related myocardial injury in ischemic heart diseases.


Assuntos
Ferroptose , Isquemia Miocárdica , Traumatismo por Reperfusão Miocárdica , Humanos , RNA Circular/genética , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Ferroptose/genética , Nicotinamida Fosforribosiltransferase/genética , Nicotinamida Fosforribosiltransferase/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismo , Miócitos Cardíacos/metabolismo , Apoptose
4.
BMC Cardiovasc Disord ; 23(1): 119, 2023 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-36890463

RESUMO

OBJECTIVE: Previous reports on the epidemiology, influencing factors, and the prognostic value of the components of PR interval in hospitalized heart failure patients were limited. METHODS: This study retrospectively enrolled 1182 patients hospitalized with heart failure from 2014 to 2017. Multiple linear regression analysis was used to explore the association between the components of PR interval and the baseline parameters. The primary outcome was all-cause death or heart transplantation. Multivariable-adjusted Cox proportional hazard regression models were constructed to explore the predictive value of the components of PR interval for the primary outcome. RESULTS: In multiple linear regression analysis, higher height (for every 10 cm increase in height: regression coefficient 4.83, P < 0.001) as well as larger atrial and ventricular size were associated with larger P wave duration but not with PR segment. The primary outcome occurred in 310 patients after an average follow-up of 2.39 years. Cox regression analyses revealed that the increase in PR segment was an independent predictor of the primary outcome (every 10 ms increase: hazard ratio 1.041, 95% confidence interval [CI] 1.010-1.083, P = 0.023), whereas the P wave duration did not show significant correlation. When adding the PR segment to an initial prognostic prediction model, the likelihood ratio test and categorical net reclassification index (NRI) showed a significant improvement, but the increase in C-index was not significant. In subgroup analysis, increased PR segment was an independent predictor of the primary endpoint in patients taller than 170 cm (each 10 ms increase: hazard ratio 1.153, 95% CI 1.085-1.225, P < 0.001) but not the shorter group (P for interaction = 0.006). CONCLUSIONS: In hospitalized patients with heart failure, longer PR segment was an independent predictor of the composite endpoint of all-cause death and heart transplantation, especially in the taller group, but it had limited significance in improving the prognostic risk stratification of this population.


Assuntos
Insuficiência Cardíaca , Humanos , Prognóstico , Estudos Retrospectivos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/terapia , Análise Multivariada
5.
Front Biosci (Landmark Ed) ; 27(6): 194, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35748270

RESUMO

BACKGROUND: Polyamines have been demonstrated to be beneficial to porcine intestinal development. Our previous study showed that putrescine mitigates intestinal atrophy in weanling piglets and suppresses inflammatory response in porcine intestinal epithelial cells, it is still unknown the role of spermidine in mediating putrescine function. OBJECTIVE: The current study aimed to investigate the effect of spermidine on the proliferation, migration, and inflammatory response in porcine intestinal epithelial cells (IPEC-J2 cell line). METHODS: The effects of spermidine on proliferation and migration of IPEC-J2 cells were measured. Difluoromethyl ornithine (DFMO) and diethylglyoxal bis (guanylhydrazone) (DEGBG) were used to block the production of putrescine and spermidine, respectively. A cell inflammation model was established with lipopolysaccharides (LPS) stimulation. Gene expression and protein abundance were determined by real-time quantitative PCR and western blotting, respectively. RESULT: Spermidine significantly enhanced cell proliferation in DFMO (or/and) DEGBG treated IPEC-J2 cells (p < 0.05). Pretreatment with putrescine restored cell growth inhibited by DFMO but did not prevent the decrease in cell proliferation caused by DEGBG (p > 0.05). Similarly, spermidine but not putrescine significantly elevated the rate of migration in DEGBG treated IPEC-J2 cells (p < 0.05). Spermidine deprivation by DEGBG dramatically enhanced mRNA abundance of pro-inflammatory cytokines IL-8, IL-6, and TNF-α (p < 0.05), and the addition of spermidine attenuated excessive expression of those inflammatory pro-inflammatory cytokines, moreover, spermidine but not putrescine suppressed the phosphorylation of NF-κB induced by DEGBG. Spermidine supplementation also significantly suppressed LPS-induced the expression of TNF-α. CONCLUSIONS: The present study highlights a novel insight that putrescine may be converted into spermidine to modulate cell proliferation, migration, and inflammatory response on porcine enterocytes.


Assuntos
Putrescina , Espermidina , Animais , Proliferação de Células , Citocinas , Eflornitina/farmacologia , Enterócitos/metabolismo , Lipopolissacarídeos/farmacologia , Putrescina/metabolismo , Putrescina/farmacologia , Espermidina/metabolismo , Espermidina/farmacologia , Suínos , Fator de Necrose Tumoral alfa
6.
J Clin Lipidol ; 15(1): 116-123, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33414089

RESUMO

BACKGROUND: CYP27A1 is the disease-causing gene of cerebrotendinous xanthomatosis (CTX). As a treatable lipid storage disease, early treatment can improve the prognosis. However, CTX patients reported in the literature are mostly adult patients; the phenotype spectrum of CTX in the infantile population remains elusive. OBJECTIVE: We aimed to investigate the phenotype spectrum of infants who carried pathogenic or likely pathogenic variants in the CYP27A1 gene and were suspected of having CTX. METHODS: From June 2014 to May 2020, infants with pathogenic or likely pathogenic variants in CYP27A1 gene were enrolled, who underwent next-generation sequencing or Sanger sequencing in Children's Hospital of Fudan University. Patient characteristics, clinical treatments and outcomes were extracted from electronic medical records. RESULTS: A total of 17 patients with an average onset age of 8 (1-42) days were found. The average diagnosis age was ten months. Cholestasis was the dominant symptom of these infants. Thirteen variants were detected, of which c.379C > T was a hotspot variant (26.5% alleles, 9/34). Cholestatic CTX is usually underestimated, but it could be severe or even fatal in infancy. For outcomes, 5 suffered from liver failure (36%, 5/14), 1 still showed cholestasis (7%, 1/14), 7 were asymptomatic (50%, 7/14), and 1 presented seizure and developmental delay in later childhood (7%, 1/14). CONCLUSION: Based on this infantile cohort, we concluded that it is necessary to consider the possibility of CTX caused by CYP27A1 gene variants for infants with cholestasis.


Assuntos
Xantomatose Cerebrotendinosa , Criança , Colestanotriol 26-Mono-Oxigenase , Humanos , Lactente , Masculino
7.
Cardiovasc Diabetol ; 20(1): 25, 2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-33494751

RESUMO

BACKGROUND: Although the benefits of sodium-glucose cotransporter 2 inhibitors (SGLT2i) on cardiovascular events have been reported in patients with type 2 diabetes mellitus (T2DM) with or without heart failure (HF), the impact of SGLT2i on cardiac remodelling remains to be established. METHODS: We searched the PubMed, Embase, Cochrane Library and Web of Science databases up to November 16th, 2020, for randomized controlled trials reporting the effects of SGLT2i on parameters of cardiac structure, cardiac function, plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) level or the Kansas City Cardiomyopathy Questionnaire (KCCQ) score in T2DM patients with or without chronic HF. The effect size was expressed as the mean difference (MD) or standardized mean difference (SMD) and its 95% confidence interval (CI). Subgroup analyses were performed based on the stage A-B or stage C HF population and HF types. RESULTS: Compared to placebo or other antidiabetic drugs, SGLT2i showed no significant effects on left ventricular mass index, left ventricular end diastolic volume index, left ventricular end systolic volume index, or left atrial volume index. SGLT2i improved left ventricular ejection fraction only in the subgroup of HF patients with reduced ejection fraction (MD 3.16%, 95% CI 0.11 to 6.22, p = 0.04; I2 = 0%), and did not affect the global longitudinal strain in the overall analysis including stage A-B HF patients. SGLT2i showed benefits in the E/e' ratio (MD - 0.45, 95% CI - 0.88 to - 0.03, p = 0.04; I2 = 0%), plasma NT-proBNP level (SMD - 0.09, 95% CI - 0.16 to - 0.03, p = 0.004; I2 = 0%), and the KCCQ score (SMD 3.12, 95% CI 0.76 to 5.47, p  = 0.01; I2 = 0%) in the overall population. CONCLUSION: The use of SGLT2i was associated with significant improvements in cardiac diastolic function, plasma NT-proBNP level, and the KCCQ score in T2DM patients with or without chronic HF, but did not significantly affect cardiac structural parameters indexed by body surface area. The LVEF level was improved only in HF patients with reduced ejection fraction.


Assuntos
Função do Átrio Esquerdo/efeitos dos fármacos , Remodelamento Atrial/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Insuficiência Cardíaca/tratamento farmacológico , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Função Ventricular Esquerda/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos , Idoso , Biomarcadores/sangue , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Doença Crônica , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Recuperação de Função Fisiológica , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Volume Sistólico/efeitos dos fármacos , Fatores de Tempo , Resultado do Tratamento
8.
Nat Cell Biol ; 22(11): 1319-1331, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33020597

RESUMO

PIWI-interacting RNAs (piRNAs) are abundantly expressed during cardiac hypertrophy. However, their functions and molecular mechanisms remain unknown. Here, we identified a cardiac-hypertrophy-associated piRNA (CHAPIR) that promotes pathological hypertrophy and cardiac remodelling by targeting METTL3-mediated N6-methyladenosine (m6A) methylation of Parp10 mRNA transcripts. CHAPIR deletion markedly attenuates cardiac hypertrophy and restores heart function, while administration of a CHAPIR mimic enhances the pathological hypertrophic response in pressure-overloaded mice. Mechanistically, CHAPIR-PIWIL4 complexes directly interact with METTL3 and block the m6A methylation of Parp10 mRNA transcripts, which upregulates PARP10 expression. The CHAPIR-dependent increase in PARP10 promotes the mono-ADP-ribosylation of GSK3ß and inhibits its kinase activity, which results in the accumulation of nuclear NFATC4 and the progression of pathological hypertrophy. Hence, our findings reveal that a piRNA-mediated RNA epigenetic mechanism is involved in the regulation of cardiac hypertrophy and that the CHAPIR-METTL3-PARP10-NFATC4 signalling axis could be therapeutically targeted for treating pathological hypertrophy and maladaptive cardiac remodelling.


Assuntos
Adenosina/análogos & derivados , Ventrículos do Coração/enzimologia , Hipertrofia Ventricular Esquerda/enzimologia , Metiltransferases/metabolismo , Miócitos Cardíacos/enzimologia , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Função Ventricular Esquerda , Adenosina/metabolismo , Animais , Células Cultivadas , Modelos Animais de Doenças , Regulação Enzimológica da Expressão Gênica , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Ventrículos do Coração/patologia , Hipertrofia Ventricular Esquerda/genética , Hipertrofia Ventricular Esquerda/patologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Metilação , Metiltransferases/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos Cardíacos/patologia , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/metabolismo , Poli(ADP-Ribose) Polimerases/genética , Proteínas Proto-Oncogênicas/genética , Estabilidade de RNA , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Transdução de Sinais , Remodelação Ventricular
9.
Inorg Chem ; 59(8): 5475-5482, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32233471

RESUMO

Polar crystal structures have attracted more and more attention, due to their unique characteristics, such as ferroelectricity, piezoelectricity, and nonlinear optical property, etc. However, the construction of polar materials is always accidental, and finding an effective synthesis strategy to construct polar materials remains a challenge. Herein, inorganic-organic hybrid compounds of [C7H14N][FeCl4] (1) ([C7H14N] = quinuclidinium cation) and [C7H14N][GeCl3] (2) were prepared, respectively, to verify the beneficial effect of polar anions on the construction of polar crystals. Compound 1 crystallized in the Pbca space group, while 2 belongs to the P43 space group at room temperature. Investigation into the structure of 2 reveals that the polarity of 2 derives from the triangular pyramid structure of [GeX3]- with lone pair electrons. Meanwhile, 2 undergoes a phase transition from the P43 space group to the center Pm3m at 385 K, leading to the optic-electric switching property. Thus, the present work exhibits the advantage of [GeX3]- as the inorganic constituent component in the hybrid polar materials and provides an effective approach for the construction of a polar molecule-based crystal with a switchable property.

10.
Dig Dis Sci ; 65(10): 2925-2936, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31900718

RESUMO

BACKGROUND: Due to the multi-factorial etiology of hepatic fibrosis, multi-target therapeutics based on combinatory drugs is known to be a promising strategy for the disease. AIMS: The present study attempted to test the hypothesis that astragaloside IV combined with ferulic acid synergistically inhibits activation of hepatic stellate cells in vivo. METHODS: Bile duct-ligated rats were treated with astragaloside IV or/and ferulic acid for 28 days. Liver fibrosis was measured by histological examination. The oxidative stress-related biomarkers were measured with spectrophotometry. Expressions of mRNA and protein were measured by real-time PCR and Western blotting. RESULTS: Bile duct-ligated rat treatment with astragaloside IV and ferulic acid in combination resulted in synergistic alleviation of hepatic fibrosis. Simultaneously, activation of hepatic stellate cells was significantly inhibited by the combination therapy when compared with astragaloside IV or ferulic acid alone. Interestingly, astragaloside IV, but not ferulic acid, induced accumulation of Nrf2 in the nucleus, synthesized antioxidant enzymes through negative regulation of glycogen synthase kinase-3ß, scavenged reactive oxygen species, and, in turn, suppressed hepatic stellate cells activation in bile duct-ligated rats. Conversely, ferulic acid, but not astragaloside IV, suppressed TGF-ß1 and its receptors expression, which resulted in downregulation of Smad3 and Smad4. CONCLUSIONS: These findings suggest that the combination of astragaloside IV and ferulic acid synergistically induces deactivation of hepatic stellate cells through inhibition of the TGF-ß pathway and activation of the Nrf2 pathway, and suggest that combination of astragaloside IV and ferulic acid is a promising candidate for the treatment of hepatic fibrosis.


Assuntos
Colestase/complicações , Ácidos Cumáricos/farmacologia , Células Estreladas do Fígado/efeitos dos fármacos , Cirrose Hepática Biliar/prevenção & controle , Fígado/efeitos dos fármacos , Saponinas/farmacologia , Triterpenos/farmacologia , Animais , Ducto Colédoco/cirurgia , Modelos Animais de Doenças , Sinergismo Farmacológico , Quimioterapia Combinada , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Ligadura , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática Biliar/etiologia , Cirrose Hepática Biliar/metabolismo , Cirrose Hepática Biliar/patologia , Masculino , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais , Proteína Smad3/metabolismo , Proteína Smad4/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
11.
Int Heart J ; 60(3): 608-617, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31105142

RESUMO

The aim of the present study was to investigate the performance of low keV mono-energetic reconstructions in spectral coronary computed tomography angiography (CCTA) using spectral detector CT (SDCT) with reduced contrast media and radiation dose.Sixty patients were randomly assigned to Groups A and B (both n = 30) to undergo CCTA on a dual-layer SDCT with tube voltage 120 kVp and 100 kVp (average tube current: 108.5 and 73.8 mAs, respectively), with contrast media volume of 36 mL used in both groups. The mono-energetic 40-80 keV and conventional 120 kVp images in Group A and conventional 100 kVp images in Group B were reconstructed. Quantitative and qualitative image quality (IQ) were evaluated in the aortic root and distal segments of the coronary arteries.The patient characteristics were not significantly different between the two groups (all P≥ 0.47), nor was the effective radiation dose (1.5 ± 0.3 and 1.4 ± 0.3 mSv, P = 0.20). The quantitative IQ in aorta and coronary arteries of mono-energetic 40-60 keV was superior to conventional 120 kVp and 100 kVp images (all P < 0.05). The noise in spectral images was lower compared to conventional images (all P < 0.01). The subjective IQ score of 40-50 keV images was not significantly different from that of 100 kVp images (P > 0.8).The mono-energetic 40-50 keV reconstructions from spectral CCTA using SDCT provide improved IQ compared to conventional techniques while facilitating reduced radiation dose and contrast media.


Assuntos
Angiografia por Tomografia Computadorizada/instrumentação , Estenose Coronária/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/normas , Idoso , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Distribuição Aleatória , Sensibilidade e Especificidade
12.
Org Biomol Chem ; 17(19): 4869-4878, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-31041985

RESUMO

An efficient one pot, three component synthesis of C3 sulfonamidomethylated imidazopyridines has been disclosed under metal-free conditions, which utilized the commercially available and renewable reagent methanol as the main methylene source. A wide range of substituted imidazopyridines and sulfamides/amines were well tolerated to afford the corresponding products in up to 92% yield. In the isotopic labelling experiment, it was found that a minor part of the methylene also originated from DTBP. Moreover, the radical scavenger reactions were conducted, which suggested that a free-radical mechanism was probably not involved. The current methodology featured several advantages, including broad substrate scope, good functional group tolerance and high reaction efficiency.

13.
Inorg Chem ; 58(1): 655-662, 2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30576116

RESUMO

Driven by the rapidly increasing demand for technological applications, multifunctional materials have been one important research area, which are expected to enhance the capacity and versatility of materials in various applications. Nevertheless, combining more than three functions in one molecular compound is still a challenge. Molecular solid-solid phase transition materials could exhibit switchable properties, which could have potential applications such as switches, sensors, and memory devices. However, these switchable molecular materials are rarely researched as thermal energy storage materials. In this work, we report the coexistence of thermal energy storage and magnetic-optic-electric triple switching in a plastic crystal, trimethylchloromethyl ammonium tetrachloroferrate(III), ([(CH3)3NCH2Cl][FeCl4], referred to as 1). 1 undergoes plastic phase transition at near room temperature (326 K) induced by the order-disorder of the ions. The magnetic-optic-electric triple switching in 1 could be triggered by temperature stimuli near room temperature. Meanwhile, with utilization of large latent heat during the phase transition process and sensible heat, the energy storage in 1 is up to 107 J g-1 from 293 to 343 K, demonstrating its thermal energy storage application in solar energy systems and industrial sectors. This work particularly exhibits the advantages of plastic molecular materials as thermal energy storage materials and introduces the thermal energy storage into the multi-switchable plastic phase transition molecular materials, which will give extra flexibility for the design of new types of multifunctional materials.

14.
Adv Mater ; 30(52): e1803716, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30370676

RESUMO

Magnetoelectric materials with a large magnetoelectric response, a low operating magnetic (or electric) field, and a room-temperature (or higher) operating temperature are of key importance for practical applications. However, such materials are extremely rare because a large magnetoelectric response often requires strong coupling between spins and electric dipoles. Herein, an example of a magnetoelectric composite is prepared by using a room-temperature multiaxial molecular-ionic ferroelectric, tetramethylammonium tetrachlorogallate(III) (1). Investigation of the magnetoelectric effect of the magnetoelectric laminate composite indicates that its room-temperature magnetoelectric voltage coefficient (αME ) is as high as 186 mV cm-1 Oe-1 at HDC = 275 Oe and at the HAC frequency of ≈39 kHz, providing a valid approach for the preparation of magnetoelectric materials and adding a new member to the magnetoelectric material family.

15.
Eur J Radiol ; 103: 131-138, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29803379

RESUMO

PURPOSE: To investigate and compare image quality of monoenergetic reconstructions from spectral NCCT to conventional 120 kVp images acquired at a similar dose. MATERIALS AND METHODS: Patients undergoing NCCT on a dual-layer spectral detector CT (n = 30) and a conventional CT (n = 30) were enrolled in the study. The spectral detector CT data was reconstructed at monoenergetic images from 40 to 140 keV in 5-keV increments and 65-70 keV in 1-keV increments (Group A1) and using single energy CT equivalent reconstruction (Group A2). The reference conventional 120kVp images (Group B) were acquired using a standard-of-care protocol with the same radiation dose. We evaluated the image quality of monoenergetic images and determined the optimal keV level using HU attenuation, noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), artifact evaluation in posterior fossa by placing region-of-interest (ROI) and subjective image score by 2 radiologists independently using a 4-point scale (1-excellent, 4-undiagnostic). RESULTS: The SNR and subjective image score were optimal at 66-70keV, while monoenergetic 68 keV images with a higher SNR (18.48 ±â€¯1.94, 15.55 ±â€¯1.56 and 14.33 ±â€¯1.38 for Group 68keV, A2 and B respectively, p < 0.001), CNR (4.09 ±â€¯0.65, 3.43 ±â€¯0.56 and 3.52 ±â€¯0.55 for Group 68keV, A2 and B respectively, p < 0.001) and a lower noise (1.80 ±â€¯0.19, 2.11 ±â€¯0.19 and 2.25 ±â€¯0.25 for Group 68keV, A2 and B respectively, p < 0.001). CONCLUSION: Spectral NCCT monoenergetic reconstructions at 68 keV improve image quality and reduce artifact compared to conventional single energy CT without radiation dose penalty.


Assuntos
Encefalopatias/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Artefatos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Razão Sinal-Ruído
16.
J Org Chem ; 81(18): 8370-7, 2016 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-27557624

RESUMO

A novel iron-involved tosylmethylation of imidazo[1,2-α]pyridines with p-toluenesulfonylmethyl isocyanide in a solvent mixture of H2O and PEG400 under an Ar atmosphere has been developed. This protocol provides a facile synthetic route for the functionalization of the imidazo[1,2-α]pyridine scaffold with broad substrate compatibility, which is less expensive and environmentally friendly. The current methodology could further enable regioselective C-H tosylmethylation of indole at the C3 position. Also, p-toluenesulfonylmethyl isocyanide was utilized as the tosylmethylating reagent for the first time.


Assuntos
Imidazóis/química , Ferro/química , Nitrilas/química , Piridinas/química , Compostos de Tosil/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Espectrometria de Massas , Metilação , Espectroscopia de Prótons por Ressonância Magnética
17.
J Org Chem ; 81(10): 4002-11, 2016 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-27125957

RESUMO

A nickel(II)-catalyzed alkynylation/annulation cascade via double C-H cleavage has been successfully achieved. This methodology adopted a removable N,O-bidentate directing group with a broad range of amide substrates and terminal alkynes being well tolerated. The catalytic system allowed for atom-economical and environmentally benign one-pot construction of the corresponding 3-methyleneisoindolin-1-one derivatives using O2 as the external oxidant.

18.
Yao Xue Xue Bao ; 51(4): 588-94, 2016 04.
Artigo em Chinês | MEDLINE | ID: mdl-29859528

RESUMO

This study was designed to investigate the effect of gastrodin(GAS) against ß-amyloid plaques in 5×FAD Alzheimer's disease(AD) transgenic mice, and utilize 117 cell model(over-expression of Aß and ß-secretase) to explore the underlying mechanism. 5×FAD mice model were randomly divided into three groups, including GAS-high dose group(GAS-H, 200 mg·kg(-1)·d(-1)), GAS-middle dose group(GAS-M, 100 mg·kg(-1)·d(-1)) and GAS-low dose group(GAS-L, 50 mg·kg(-1)·d(-1)). Meanwhile, the wild type mice were used in the control group. After being treated with GAS for three months, 5×FAD mice were evaluated by Morris water maze for the learning and memory ability and by ELISA for Aß in the cerebral homogenate. Then, Aß plaques in the hippocampus and cortex of 5×FAD mice were observed and analyzed with immunohistochemical staining. The cell apoptosis rate and the cell viability were determined in vitro, after the cells were treated with different concentrations of GAS(10, 25, 50 and 100 µmol·L(-1)). Furthermore, Intracelluar/extracelluar Aß were determined by ELISA. Effects of GAS on BACE(ß-secretase site APP cleaving enzyme) m RNA and protein expression were analyzed in 117 cell models by Q-PCR and Western blotting. The results suggest that GAS is able to restore the learning and memory capacity of 5×FAD mice, and reduce Aß in the cerebral homogenate and Aß plaques in the brain. Compared with the untreated transgenic positive group, Aß plaques were declined in hippocampus and cortex of GAS-H group by 93.28% and 88.88%, and Aß was reduced in the cerebral homogenate by 55.74%. In vitro study suggests a dose-dependent effect of GAS in reducing Aß in 117 cell models. When the cells were treated with 100 µmol·L(-1) GAS, extracelluar Aß and intracellular Aß of 117 cells were reduced by 63.1% and 49.1%. BACE expression was largely suppressed in m RNA by 32.9%(P < 0.01). At 50 µmol·L(-1) GAS, the protein level was declined by 47.9%(P < 0.05). In conclusion, GAS inhibits Aß production and accumulation by inhibiting ß-secretase.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Álcoois Benzílicos/farmacologia , Encéfalo/patologia , Glucosídeos/farmacologia , Placa Amiloide/tratamento farmacológico , Peptídeos beta-Amiloides , Precursor de Proteína beta-Amiloide , Animais , Modelos Animais de Doenças , Memória , Transtornos da Memória , Camundongos , Camundongos Transgênicos
19.
Mol Neurobiol ; 53(9): 6489-6500, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26611834

RESUMO

Prenatal lead exposure is associated with poor intellectual development in children. However, there are few breakthroughs in therapeutic intervention of developmental lead neurotoxicity. The aim of this study is to evaluate the hypothesis that ferulic acid-mediated promotion of neurite outgrowth following lead exposure might mainly result from its antioxidant capability by extracellular signal-regulated kinases 1 and 2 (ERK1/2) activation of nuclear factor erythroid 2-related factor 2 (Nrf2). Exposure of PC12 cells to lead acetate inhibits neurite outgrowth and causes oxidative stress as measured by ROS, LPO, GSH/GSSG, and NAD+/NADH. FA treatment significantly, although not completely, protected the cells against lead acetate-induced neurite outgrowth inhibition. The effects of FA could be blocked by PD98059, zinc protoporphyrin (Zn-PP), and Nrf2 shRNA. In addition, FA induced heme oxygenase 1 (HO-1) gene expression, enhanced antioxidant response element (ARE) promoter activity, promoted ERK1/2 phosphorylation, and Nrf2 translocation in PC12 cells exposed to lead acetate. ERK1/2 locate upstream of Nrf2 and regulate Nrf2-dependent HO-1 expression in antioxidative effects of FA. Our results suggest that FA is a promising candidate for treatment of developmental lead neurotoxicity. These promising findings warrant future investigation evaluating the FA-mediated potentiation of neurite outgrowth following lead exposure in vivo.


Assuntos
Ácidos Cumáricos/farmacologia , Heme Oxigenase-1/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Crescimento Neuronal/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Animais , Elementos de Resposta Antioxidante , Ácidos Cumáricos/química , Modelos Biológicos , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Compostos Organometálicos , Estresse Oxidativo/efeitos dos fármacos , Células PC12 , Ratos , Transdução de Sinais/efeitos dos fármacos
20.
Yao Xue Xue Bao ; 49(6): 800-6, 2014 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-25212023

RESUMO

This study is to screen the Chinese herbal compounds which could inhibit the production of Abeta and investigate the underlying mechanism. Ten types of compounds which have potential value in the treatment of AD were selected as initial screening trial. The cell models which used could overexpress Abeta and beta-secretases or Abeta and gamma-secretases. Extracellular Abeta was determined by ELISA after the cell models treated with different concentrations of compounds (0.5-100 micromol x L(-1)), separately. Then the compounds were selected which could inhibit extracellular Abeta and their best concentration ranges were decided, too. Furthermore, the cell viability and apoptosis rate, the level of intracellular Abeta, beta and gamma-secretases were determined after the cell models treated with different concentrations of selected compounds. The results showed that 4 of the 10 compounds could reduce the level of extracellular Abeta; they were cryptotanshinone, astragalosides, gastrodin and paeoniflorin, and their best concentration ranges were 0.5-5.0, 0.5-5.0, 5.0-50, 1.0-25 micromol x L(-1), respectively. Further study indicated that the 4 selected compounds were nontoxic to the cellular models and lowering intracellular Abeta were more effective compared with extracellular; of which astragalosides and gastrodin showed dose-dependent inhibition to the activities of beta and gamma-secretases, with the maximum inhibiting rates of 78.2% and 80.3%, respectively. In conclusion, cryptotanshinone, astragalosides, gastrodin and paeoniflorin could inhibit the expression and secretion of Abeta, and the underlying inhibiting mechanism of astragalosides and gastrodin were related with the reduction of the beta and gamma-secretase activities, respectively.


Assuntos
Peptídeos beta-Amiloides/antagonistas & inibidores , Medicamentos de Ervas Chinesas/farmacologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Apoptose , Álcoois Benzílicos/farmacologia , Linhagem Celular , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Glucosídeos/farmacologia , Humanos , Monoterpenos/farmacologia , Fenantrenos/farmacologia , Saponinas/farmacologia
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