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1.
Inorg Chem ; 63(6): 3091-3098, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38295272

RESUMO

Rechargeable magnesium-ion batteries (MIBs) hold significant promise as an alternative to conventional lithium-ion technology driven by their natural abundance and low-cost, high-energy density, and safety features. Spinel oxides, including MgCrVO4, have emerged as a prospective cathode material for MIBs due to their promising combination of capacity, operating potential, and cation mobility. However, the structural evolution, phase stability, and processes of Mg mobility in MgCrVO4 during electrochemical cycling are poorly understood. In this study, we synthesized a single-phase, solid solution of spinel oxide MgCrVO4 and employed operando X-ray diffraction to couple physical properties with structural changes during cycling. Our results revealed a two-phase reaction mechanism coupled with a solid-solution-like reaction, highlighting the complicated transformation between two distinct phases in the MgCrVO4 lattice during Mg (de)intercalation. Rietveld refinement of the operando data provided valuable insights into the mechanism of the Cr/V-based spinel oxide, shedding light on the transition between the two phases and their roles in Mg-ion (de)intercalation. This study contributes to a deeper understanding of the structural dynamics in multivalent cathode materials and sets the stage for the development of advanced Mg-ion cathodes with enhanced performance and stability.

2.
J Magn Reson Imaging ; 57(3): 800-809, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35715897

RESUMO

BACKGROUND: Obesity is highly prevalent in patients with hypertrophic cardiomyopathy (HCM) and believed to influence its phenotype. PURPOSE: To explore the effects of obesity on left ventricular (LV) remodeling and long-term clinical course in Chinese patients with HCM. STUDY TYPE: Longitudinal. POPULATION: A total of 247 patients with HCM classified according to body mass index (BMI) (normal weight: BMI = 18.0-22.9 kg/m2 [N = 90]; overweight: BMI = 23.0-24.9 kg/m2 [N = 58]; and obese: BMI ≥ 25 kg/m2 [N = 99]). FIELD STRENGTH/SEQUENCE: 3.0 T/Balanced steady-state free precession sequence and phase-sensitive inversion recovery late gadolinium enhancement (LGE) sequence. ASSESSMENT: LV function and geometry were measured. LV peak strain analysis was performed. The presence and percentage of LGE in the LV were recorded. The endpoints including heart failure, sudden cardiac death, and overall composite outcome were assessed during a median follow-up of 4.1 years (interquartile range, 3.0-6.2 years). STATISTICAL TESTS: One-way analysis of variance, Kruskal-Wallis test, or chi-square test; Pearson correlation coefficient (r); multivariable linear regression analysis; Kaplan-Meier survival analysis; and Cox proportional hazards model analysis were conducted. A two-tailed P-value < 0.05 was considered statistically significant. RESULTS: Obese patients exhibited a significant progressive increase in LV mass compared with normal-weight patients. The magnitude of all LV strain indices gradually and significantly decreased as BMI increased, whereas LV ejection fraction was not significantly different among BMI groups (P = 0.364). Multivariable linear regression analysis showed that obesity had a significant association with impaired strain indices as well as with indexed LV mass. Multivariable Cox model analysis retained obesity as an independent marker for future endpoints, and conveyed a > 3-fold increase in risk compared with patients with normal weight (hazard ratio, 3.04; 95% confidence interval, 1.07-6.57). DATA CONCLUSION: Obesity is an important environmental modifier that is associated with adverse LV remodeling and is independently associated with future clinical outcomes in Chinese patients with HCM. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.


Assuntos
Cardiomiopatia Hipertrófica , Meios de Contraste , Humanos , Remodelação Ventricular , População do Leste Asiático , Imagem Cinética por Ressonância Magnética , Gadolínio , Cardiomiopatia Hipertrófica/complicações , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Imageamento por Ressonância Magnética , Obesidade/complicações , Obesidade/diagnóstico por imagem , Função Ventricular Esquerda , Valor Preditivo dos Testes
3.
Heart Fail Rev ; 27(5): 1899-1909, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35064397

RESUMO

Myocardial fibrosis predisposes the development of main adverse cardiovascular events (MACEs) in various cardiac disorders. Native T1 derived from cardiac magnetic resonance allows the quantitative assessment of myocardial fibrosis without the use of contrast media. However, the prognostic value of native T1 in risk stratification remains uncertain. We searched MEDLINE®, Embase, and the Cochrane Library for cohort studies up to July 31, 2021, that reported prognostic data for native T1 in various cardiac disorders; the studies enrolling patients with myocardial iron or amyloid deposition, edema, and inflammation were excluded. A random effects meta-analysis was conducted. Heterogeneity was assessed using I2 statistic. Nineteen studies with 5,380 patients were included in this meta-analysis. Patients with MACEs had higher native T1 than those without [weighted mean difference: 27.35 (15.55-39.16), I2 = 23.2%]. The increase of native T1 per 1 ms [pooled adjusted hazard ratio (HR): 1.02 (1.00-1.03), I2 = 41.8%] and per ≥ 10 ms [pooled adjusted HR: 1.11 (1.07-1.16), I2 = 28.6%] was both associated with the development of MACEs; the categorical variable derived from native T1 also has the predicative value for MACEs [pooled adjusted HR: 5.97 (3.69-9.68), I2 = 0.0%].Myocardial native T1 potentially serves as a prognostic biomarker in patients with various cardiac disorders. Different variable definitions of native T1 have different positively predictive value for outcome; the categorical variable derived from native T1 may be more helpful in identifying high-risk patients.


Assuntos
Cardiomiopatias , Doenças Cardiovasculares , Cardiomiopatias/patologia , Meios de Contraste , Fibrose , Humanos , Imagem Cinética por Ressonância Magnética , Miocárdio/patologia , Valor Preditivo dos Testes , Prognóstico
4.
J Magn Reson Imaging ; 56(3): 790-800, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35130580

RESUMO

BACKGROUND: Mitral regurgitation (MR) is a comorbidity of myocardial infarction (MI), which may promote the incidence of adverse cardiovascular clinical events. However, it is not yet completely understood how MR in MI patients is associated with impaired myocardial deformation. PURPOSE: To determine the damaging myocardium effects of MR in MI patients in terms of the global peak strain (PS) and left ventricular (LV) function, and evaluate the independent risk factors impacting LV deformation after MI. STUDY TYPE: Retrospective. POPULATION: One hundred eighty-six MI patients (17.7% female) and 84 normal control subjects (27.4% female). FIELD STRENGTH/SEQUENCE: 3.0T; late gadolinium enhancement sequence, balanced steady-state free precession. ASSESSMENT: LV function and LV global PS (global radial peak strain [GRPS]; global circumferential peak strain [GCPS]; and global longitudinal peak strain [GLPS]) were compared among normal controls, MI without MR (MR-) and MI with MR (MR+, mild, moderate, severe) patients. STATISTICAL TESTS: One-way analysis of variance (ANOVA) test, Mann-Whitney U test, Kruskal-Wallis test, and multiple linear regressions were used. A P value <0.05 indicated statistically significant difference (two-tailed). RESULTS: The MI (MR+) patients showed significantly lower LV global PS than both MI (MR-) and control groups in three directions (GRPS 16.66 ± 7.43%; GCPS -11.27 ± 4.27%; GLPS -7.75 ± 3.44%), and significantly higher LV end-systolic (128.85 [87.91, 188.01] mL) and end-diastolic volumes (210.29 [164.07, 264.00] mL) and significantly lower LV ejection fraction (38.23 ± 13.02%). Multiple regression analysis demonstrated that MR was independently associated with LV GCPS (ß = -0.268) and GLPS (ß = -0.320). LV infarct size was an independent indicator of LV GRPS (ß = -0.215) and GCPS (ß = -0.222). LV end-diastolic volume was an independent indicator of LV GRPS (ß = -0.518), GCPS (ß = -0.503), and GLPS (ß = -0.331). DATA CONCLUSION: MR may further exacerbate the reduction of LV global peak strains and function. The MR, infarct size, and LV end-diastolic volume can be used as independent association indicators for LV global PS in MI (MR+) patients. LEVEL OF EVIDENCE: 4 Technical Efficacy Stage: 2 TOC Category: Chest.


Assuntos
Insuficiência da Valva Mitral , Infarto do Miocárdio , Disfunção Ventricular Esquerda , Meios de Contraste , Feminino , Gadolínio , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Insuficiência da Valva Mitral/diagnóstico por imagem , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/patologia , Estudos Retrospectivos , Volume Sistólico , Disfunção Ventricular Esquerda/etiologia , Função Ventricular Esquerda
5.
J Magn Reson Imaging ; 55(2): 555-564, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34245075

RESUMO

BACKGROUND: The pathophysiological changes in the remote myocardium after acute myocardial infarction (MI) remains less understood. PURPOSE: To assess the inflammation in the remote myocardium post-MI and its association with left ventricular (LV) remodeling using T2 mapping. STUDY TYPE: Prospective. ANIMAL MODEL AND SUBJECTS: Twelve pigs at 3-day post-MI, 6 pigs at 3-month post-MI, 6 healthy pigs; 54 patients at 3-day and 3-month post-MI, 31 healthy volunteers; FIELD STRENGTH/SEQUENCE: A 3 T MRI/ steady-state free-precession sequence for T2 mapping (animals: 0, 30, and 55 msec; human: 0, 25, and 55 msec), phase-sensitive inversion recovery gradient echo for late gadolinium enhancement (LGE), balanced steady free-precession sequence for cine. ASSESSMENT: Infarcted myocardium was defined on LGE, remote T2 was measured on T2 maps. LV remodeling was evaluated as LV end-diastolic volume change index between two scans using cine. CD68 staining was conducted to detect monocyte/macrophage. STATISTICAL TESTS: Student-t test and one-way ANOVA were used to compare remote T2 with normal controls. The association of remote T2 with LV remodeling was assessed using linear regression. P values of <0.05 were used to denote statistical significance. RESULTS: Compared with healthy pigs, remote T2 significantly increased from 3 days to 3 months post-MI (31.43 ± 0.67 vs. 33.53 ± 1.15 vs. 36.43 ± 1.07 msec). CD68 staining demonstrated the inflammation in remote myocardium post-MI but not in healthy pigs. Significant remote myocardial alterations in T2 were also observed in human group (40.51 ± 1.79 vs. 41.94 ± 1.14 vs. 42.52 ± 1.71 msec). In patients, the 3-month remote T2 (ß = 0.432) and remote T2 variation between two scans (ß = 0.554) were both independently associated with LV remodeling. CONCLUSION: T2 mapping could characterize the abnormalities in the remote myocardium post-MI, which was potentially caused by the inflammatory response. Moreover, variations in remote T2 were associated with LV remodeling. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 3.


Assuntos
Infarto do Miocárdio , Remodelação Ventricular , Animais , Meios de Contraste , Gadolínio , Humanos , Inflamação/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Infarto do Miocárdio/diagnóstico por imagem , Miocárdio , Projetos Piloto , Estudos Prospectivos , Suínos
6.
Eur Radiol ; 32(10): 6850-6858, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35579712

RESUMO

OBJECTIVES: Cancer chemotherapy potentially increases the risk of myocardial ischemia. This study assessed myocardial microvascular function by cardiac magnetic resonance (CMR) first-pass perfusion in patients treated with chemotherapy for gynecologic malignancies. METHODS: A total of 81 patients treated with chemotherapy for gynecologic malignancies and 39 healthy volunteers were prospectively enrolled and underwent CMR imaging. Among the patients, 32 completed CMR follow-up, with a median interval of 6 months. The CMR sequences comprised cardiac cine, rest first-pass perfusion, and late gadolinium enhancement. RESULTS: There were no significant differences in the baseline characteristics between the patients and normal controls (all p > 0.05). Compared with the normal controls, the patients had a lower myocardial perfusion index (PI) (13.62 ± 2.01% vs. 12% (11 to 14%), p = 0.001) but demonstrated no significant variation with an increase in the number of chemotherapy cycles at follow-up (11.79 ± 2.36% vs. 11.19 ± 2.19%, p = 0.234). In multivariate analysis with adjustments for clinical confounders, a decrease in the PI was independently associated with chemotherapy treatment (ß = - 0.362, p = 0.002) but had no correlation with the number of chemotherapy cycles (r = - 0.177, p = 0.053). CONCLUSION: Myocardial microvascular dysfunction was associated with chemotherapy treatment in patients with gynecologic malignancies, and can be assessed and monitored by rest CMR first-pass perfusion. KEY POINTS: • Chemotherapy was associated with but did not aggravate myocardial microvascular dysfunction in patients with gynecologic malignancies. • Rest CMR first-pass perfusion is an ideal modality for assessing and monitoring alterations in myocardial microcirculation during chemotherapy treatment.


Assuntos
Cardiomiopatias , Neoplasias dos Genitais Femininos , Imagem de Perfusão do Miocárdio , Meios de Contraste , Circulação Coronária , Feminino , Gadolínio , Neoplasias dos Genitais Femininos/tratamento farmacológico , Humanos , Imagem Cinética por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Imagem de Perfusão do Miocárdio/métodos , Perfusão , Valor Preditivo dos Testes
7.
Fish Shellfish Immunol ; 131: 381-390, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36257552

RESUMO

The present study was conducted to investigate the dietary replacement of fish meal with poultry by-product meal (PBM) on the growth performance, immunity, antioxidant properties, and intestinal health of red swamp crayfish (Procambarus clarkia). A diet containing 20% fish meal (FM) and complex plant ingredients as the main protein resources was set as the FM group (crude protein 32%, crude lipid 6%). Four diets replacing 25%, 50%, 75%, and 100% fish meal of the FM diet with PBM were set as the PBM25, PBM50, PBM75, and PBM100 groups, respectively. Compared to the FM group, the PBM100 diet significantly decreased growth performance and feed utilization of crayfish, while markedly increasing the activity of serum aspartate aminotransferase. The immune response was depressed in crayfish fed the PBM100 diet as the activities of serum lysozyme and phenoloxidase, gene expression of anti-lipopolysaccharide factors (alf), cyclophilin A (cypa), crustin, and hemocyanin-1 (hep-1) in hepatopancreas were remarkably decreased. The activities of antioxidases and expression of antioxidant-relevant genes in the hepatopancreas were not influenced by PBM inclusion. Crayfish fed different diets exhibited no obvious symptoms of enteritis, but the PBM100 diet destructed intestinal morphology by significantly decreasing the average length of longitudinal ridges. The α-diversity and overall community structure were not significantly influenced but variations were found in the relative abundance of some genera by PBM inclusion. In summary, CAP could successfully replace 75% dietary FM in a basal diet containing 20% fish meal, while higher CAP level compromised growth performance, immunity, and intestinal histology of crayfish.


Assuntos
Astacoidea , Clarkia , Animais , Ração Animal/análise , Antioxidantes/farmacologia , Aves Domésticas , Imunidade Inata , Dieta/veterinária , Peixes
8.
Medicina (Kaunas) ; 58(10)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36295589

RESUMO

Background and Objectives: According to recent guidelines, myocardial contrast echocardiography (MCE) is recommended for detecting residual myocardial viability (MV). However, the long-term prognostic value of MV as assessed by MCE in identifying major adverse cardiac events (MACE) after acute myocardial infarction (AMI) remains undefined. Materials and Methods: We searched multiple databases, including PubMed, EMBASE, and Web of Science for studies on the prognostic value of MCE for clinical outcomes in AMI patients. The primary endpoints were MACEs during follow-up. Six studies that evaluated a total of 536 patients with a mean follow-up of 36.8 months were reviewed. Results: The pooled sensitivity and specificity of MCE for predicting MACEs were 0.80 and 0.78, respectively, and the summary operating receiver characteristics achieved an area under the curve of 0.84. The pooled relative risks demonstrated that the MV evaluated by MCE after AMI was correlated with a high risk for total cardiac events (pooled relative risk: 2.07; 95% confidence interval: 1.28-3.37) and cardiac death (pooled relative risk: 2.48; 95% confidence interval: 1.03-5.96). MV evaluated by MCE was a highly independent predictor of total cardiac events (pooled hazard ratio: 2.09, 95% confidence interval: 1.14-3.81) in patients after AMI. Conclusions: Residual MV evaluated by MCE may be an effective long-term prognostic tool for predicting MACE in patients after AMI that can provide moderate predictive accuracy. The assessment of MV by MCE may become an alternative technique with the potential to rapidly provide important information for improving long-term risk stratification in patients after AMI, at the bedside in clinical practice, especially for patients who cannot tolerate prolonged examinations. The PROSPERO registration number is CRD42020167565.


Assuntos
Ecocardiografia , Infarto do Miocárdio , Humanos , Prognóstico , Ecocardiografia/métodos , Infarto do Miocárdio/diagnóstico por imagem , Miocárdio , Coração , Valor Preditivo dos Testes
9.
J Am Chem Soc ; 143(28): 10649-10658, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34236849

RESUMO

A promising high-voltage spinel oxide cathode material MgCrMnO4 with 18% Mg/Mn inversion was synthesized successfully. A new custom operando battery device was designed to study the cation migration mechanisms of the MgCrMnO4 cathode using 0.1 M Mg(TPFA)2 electrolyte dissolved in triglyme and activated carbon as the anode. For the first time in multivalent batteries, high-quality operando diffraction data enabled the accurate quantification of cation contents in the host structure. Besides the exceptional reversibility of 12% Mg2+ insertion in Mg1-xCrMnO4 (x ≤ 1), a partially reversible insertion of excess Mg2+ during overdischarging was also observed. Moreover, the insertion/extraction reaction was experimentally shown to be accompanied by a series of cation redistributions in the spinel framework, which were further supported by density functional theory calculations. The inverted Mn is believed to be directly involved in the cation migrations, which would cause voltage hysteresis and irreversible structural evolution after overdischarging. Tuning the Mg/Mn inversion rate could provide a direct path to further optimize spinel oxide cathodes for Mg-ion batteries, and more generally, the operando techniques developed in this work should play a key role in understanding the complex mechanisms involved in multivalent ion insertion systems.

10.
Cardiovasc Diabetol ; 20(1): 185, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34521391

RESUMO

BACKGROUND: Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous syndrome with sex-specific pathophysiology. Estrogen deficiency is believed to be responsible for the development of HFpEF in women. However, estrogen deficiency does not seem to be completely responsible for the differences in HFpEF prevalence between sexes. While diabetes mellitus (DM) frequently coexists with HFpEF in women and is associated with worse outcomes, the changes in myocardial contractility among women with HFpEF and the DM phenotype is yet unknown. Therefore, we aimed to investigate sex-related differences in left ventricular (LV) contractility dysfunction in HFpEF comorbid with DM. METHODS: A total of 224 patients who underwent cardiac cine MRI were included in this study. Sex-specific differences in LV structure and function in the context of DM were determined. LV systolic strains (global longitudinal strain [GLS], circumferential strain [GCS] and radial strain [GRS]) were measured using cine MRI. The determinants of impaired myocardial strain for women and men were assessed. RESULTS: The prevalence of DM did not differ between sexes (p > 0.05). Despite a similar LV ejection fraction, women with DM demonstrated a greater LV mass index than women without DM (p = 0.023). The prevalence of LV geometry patterns by sex did not differ in the non-DM subgroup, but there was a trend toward a more abnormal LV geometry in women with DM (p = 0.072). The magnitudes of systolic strains were similar between sexes in the non-DM group (p > 0.05). Nevertheless, in the DM subgroup, there was significant impairment in women in systolic strains compared with men (p < 0.05). In the multivariable analysis, DM was associated with impaired systolic strains in women (GLS [ß = 0.26; p = 0.007], GCS [ß = 0.31; p < 0.001], and GRS [ß = -0.24; p = 0.016]), whereas obesity and coronary artery disease were associated with impaired systolic strains in men (p < 0.05). CONCLUSIONS: Women with DM demonstrated greater LV contractile dysfunction, which indicates that women with HFpEF comorbid with DM have a high-risk phenotype of cardiac failure that may require more aggressive and personalized medical treatment.


Assuntos
Diabetes Mellitus/epidemiologia , Insuficiência Cardíaca Diastólica/epidemiologia , Contração Miocárdica , Disfunção Ventricular Esquerda/epidemiologia , Função Ventricular Esquerda , Idoso , China/epidemiologia , Comorbidade , Diabetes Mellitus/diagnóstico , Feminino , Insuficiência Cardíaca Diastólica/diagnóstico por imagem , Insuficiência Cardíaca Diastólica/fisiopatologia , Humanos , Imagem Cinética por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prevalência , Medição de Risco , Fatores de Risco , Volume Sistólico , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia
11.
J Magn Reson Imaging ; 54(1): 284-289, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33433045

RESUMO

The safety profiles when performing stress oxygenation-sensitive magnetic resonance imaging (OS-MRI) have raised concerns in clinical practice. Adenosine infusion can cause side effects such as chest pain, dyspnea, arrhythmia, and even cardiac death. The aim of this study was to investigate the feasibility of breathing maneuvers-induced OS-MRI in acute myocardial infarction (MI). This was a prospective study, which included 14 healthy rabbits and nine MI rabbit models. This study used 3 T MRI/modified Look-Locker inversion recovery sequence for native T1 mapping, balanced steady-state free precession sequence for OS imaging, and phase-sensitive inversion recovery sequence for late gadolinium enhancement. The changes in myocardial oxygenation (ΔSI) were assessed under two breathing maneuvers protocols in healthy rabbits: a series of extended breath-holding (BH), and a combined maneuver of hyperventilation followed by the extended BH (HVBH). Subsequently, OS-MRI with HVBH in acute MI rabbits was performed, and the ΔSI was compared with that of adenosine stress protocol. Student's t-test, Wilcoxon rank test, and Friedman test were used to compare ΔSI in different subgroups. Pearson and Spearman correlation was used to obtain the association of ΔSI between breathing maneuvers and adenosine stress. Bland-Altman analysis was used to assess the bias of ΔSI between HVBH and adenosine stress. In healthy rabbits, BH maneuvers from 30 to 50 s induced significant increase in SI compared with the baseline (all p < 0.05). By contrast, hyperventilation for 60 s followed by 10 s-BH (HVBH 10 s) exhibited a comparable ΔSI to that of stress test (p = 0.07). In acute MI rabbits, HVBH 10 s-induced ΔSIs among infarcted, salvaged, and the remote myocardial area were no less effectiveness than adenosine stress when performing OS-MRI (r = 0.84; p < 0.05). Combined breathing maneuvers with OS-MRI have the potential to be used as a nonpharmacological alternative for assessing myocardial oxygenation in patients with acute MI. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 2.


Assuntos
Imagem Cinética por Ressonância Magnética , Infarto do Miocárdio , Animais , Meios de Contraste , Gadolínio , Humanos , Imageamento por Ressonância Magnética , Infarto do Miocárdio/diagnóstico por imagem , Miocárdio , Estudos Prospectivos , Coelhos
12.
Eur Radiol ; 31(12): 8956-8966, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34003352

RESUMO

OBJECTIVES: To explore the relationships between oxygenation signal intensity (SI) with myocardial inflammation and regional left ventricular (LV) remodeling in reperfused acute ST-segment elevation myocardial infarction (STEMI) using oxygenation-sensitive cardiovascular magnetic resonance (OS-CMR). METHODS: Thirty-three STEMI patients and 22 age- and sex-matched healthy volunteers underwent CMR. The protocol included cine function, OS imaging, precontrast T1 mapping, T2 mapping, and late gadolinium enhancement (LGE) imaging. A total of 880 LV segments were included for analysis based on the American Heart Association 16-segment model. For validation, 15 pigs (10 myocardial infarction (MI) model animals and 5 controls) received CMR and were sacrificed for immunohistochemical analysis. RESULTS: In the patient study, the acute oxygenation SI showed a stepwise rise among remote, salvaged, and infarcted segments compared with healthy myocardium. At convalescence, all oxygenation SI values besides those in infarcted segments with microvascular obstruction decreased to similar levels. Acute oxygenation SI was associated with early myocardial injury (T1: r = 0.38; T2: r = 0.41; all p < 0.05). Segments with higher acute oxygenation SI values exhibited thinner diastolic walls and decreased wall thickening during follow-up. Multivariable regression modeling indicated that acute oxygenation SI (ß = 2.66; p < 0.05) independently predicted convalescent segment adverse remodeling (LV wall thinning). In the animal study, alterations in oxygenation SI were correlated with histological inflammatory infiltrates (r = 0.59; p < 0.001). CONCLUSIONS: Myocardial oxygenation by OS-CMR could be used as a quantitative imaging biomarker to assess myocardial inflammation and predict convalescent segment adverse remodeling after STEMI. KEY POINTS: • Oxygenation signal intensity (SI) may be an imaging biomarker of inflammatory infiltration that could be used to assess the response to anti-inflammatory therapies in the future. • Oxygenation SI early after myocardial infarction (MI) was associated with left ventricular segment injury at acute phase and could predict regional functional recovery and adverse remodeling late after acute MI. • Oxygenation SI demonstrated a stepwise increase among remote, salvaged, and infarcted segments. Infarcted zones with microvascular obstruction demonstrated a higher oxygenation SI than those without. However, the former showed less pronounced changes over time.


Assuntos
Infarto do Miocárdio , Infarto do Miocárdio com Supradesnível do Segmento ST , Animais , Meios de Contraste , Gadolínio , Humanos , Inflamação/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Infarto do Miocárdio/diagnóstico por imagem , Miocárdio , Valor Preditivo dos Testes , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Suínos , Função Ventricular Esquerda , Remodelação Ventricular
13.
Eur Radiol ; 31(5): 2798-2808, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33156386

RESUMO

OBJECTIVES: To assess the longitudinal changes of microvascular function in different myocardial regions after myocardial infarction (MI) using myocardial blood flow derived by dynamic CT perfusion (CTP-MBF), and compare CTP-MBF with the results of cardiac magnetic resonance (CMR) and histopathology. METHODS: The CTP scanning was performed in a MI porcine model 1 day (n = 15), 7 days (n = 10), and 3 months (n = 5) following induction surgery. CTP-MBF was measured in the infarcted myocardium, penumbra, and remote myocardium, respectively. CMR perfusion and histopathology were performed for validation. RESULTS: From baseline to follow-up scans, CTP-MBF presented a stepwise increase in the infarcted myocardium (68.51 ± 11.04 vs. 86.73 ± 13.32 vs. 109.53 ± 26.64 ml/100 ml/min, p = 0.001) and the penumbra (104.92 ± 29.29 vs. 120.32 ± 24.74 vs. 183.01 ± 57.98 ml/100 ml/min, p = 0.008), but not in the remote myocardium (150.05 ± 35.70 vs. 166.66 ± 38.17 vs. 195.36 ± 49.64 ml/100 ml/min, p = 0.120). The CTP-MBF correlated with max slope (r = 0.584, p < 0.001), max signal intensity (r = 0.357, p < 0.001), and time to max (r = - 0.378, p < 0.001) by CMR perfusion. Moreover, CTP-MBF defined the infarcted myocardium on triphenyl tetrazolium chloride staining (AUC: 0.810, p < 0.001) and correlated with microvascular density on CD31 staining (r = 0.561, p = 0.002). CONCLUSION: CTP-MBF could quantify the longitudinal changes of microvascular function in different regions of the post-MI myocardium, which demonstrates good agreement with contemporary CMR and histopathological findings. KEY POINTS: • The CT perfusion-based myocardial blood flow (CTP-MBF) could quantify the microvascular impairment in different myocardial regions after myocardial infarction (MI) and track its recovery over time. • The assessment of CTP-MBF is in good agreement with contemporary cardiac MRI and histopathological findings, which potentially facilitates a rapid approach for pathophysiological insights following MI.


Assuntos
Infarto do Miocárdio , Imagem de Perfusão do Miocárdio , Animais , Circulação Coronária , Infarto do Miocárdio/diagnóstico por imagem , Perfusão , Valor Preditivo dos Testes , Suínos , Tomografia Computadorizada por Raios X
14.
Fish Shellfish Immunol ; 109: 1-11, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33285166

RESUMO

This study was conducted to explore the beneficial role of taurine against chronic high carbohydrate diet-induced oxidative stress, endoplasmic reticulum (ER) stress and inflammation, and to understand the underlying molecular mechanisms in turbot. Two 10-week feeding trials were simultaneously conducted. For the one, six experimental diets with graded levels of taurine supplementation (0, 0.4%, 0.8%, 1.2%, 1.6% and, 2.0%, respectively) and 15% of carbohydrate were used. For the other one, three graded levels of dietary taurine supplementation (0.4%, 1.2% and 2.0%, respectively) with 21% of carbohydrate were used. The results showed that higher expression level of inflammation cytokines and ER stress related genes were detected in higher dietary carbohydrate group. In both feeding trials, 1.2% of dietary taurine supplementation improved anti-oxidative status by decreasing the content of malondialdehyde, increasing the catalase activity and total anti-oxidative capacities. In feeding trial 1, appropriate taurine supplementation lowered contents of tumour necrosis factor-a, interleukin-6, aspartate aminotransferase and alkaline phosphatase in plasma, and decreased the expressions of pro-inflammatory cytokines, such as interleukin-8 (il-8) and interferon-γ (ifn-γ). Furthermore, dietary taurine reduced ER stress by decreasing the mRNA levels of activating transcription factor 6, protein kinase R-like endoplasmic reticulum kinase and G protein-coupled receptor 78. The optimal dietary taurine content was estimated as 1.40% based on the analysis of specific growth rate. In feeding trial 2, dietary taurine supplementation attenuated liver inflammation partly referring to significantly down-regulated mRNA levels of nuclear transcription factor-κB p65, ifn-γ, interleukin1ß and up-regulate the transcript of ribosomal protein S6 kinase 1. Dietary taurine supplementation in feeding trial 2 significantly increased the Nrf2-related factor 2 protein level and decreased the NFκB p65 protein level only at 21% of dietary carbohydrate level. Taurine can alleviate the oxidative damage and inflammation caused by 21% of dietary carbohydrate to a certain degree. Overall, the present study confirmed that dietary taurine supplementation improved growth performance and anti-oxidative response, and reduced liver inflammatory and ER stress processes induced by high dietary carbohydrate in turbot.


Assuntos
Dieta da Carga de Carboidratos/veterinária , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Linguados/imunologia , Inflamação/veterinária , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Taurina/metabolismo , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Doenças dos Peixes/induzido quimicamente , Doenças dos Peixes/tratamento farmacológico , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Fígado/metabolismo , Distribuição Aleatória , Taurina/administração & dosagem
15.
Circ J ; 84(10): 1797-1806, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32893260

RESUMO

BACKGROUND: Whether ischemic stroke per se, rather than older age or additional comorbidities, accounts for the adverse prognosis of heart failure (HF) is uncertain. The present study examineed the intrinsic association of ischemic stroke with outcomes in a propensity-matched cohort.Methods and Results:Of 1,351 patients hospitalized with HF, 388 (28.7%) had prior ischemic stroke. Using propensity score for prior ischemic stroke, estimated for each patient, a matched cohort of 379 pairs of HF patients with and without prior ischemic stroke, balanced on 32 baseline characteristics was assembled. At 30 days, prior ischemic stroke was associated with significantly higher risks of the combined endpoint of all-cause death or readmission (hazard ratio [HR]: 1.91; 95% confidence interval [CI]: 1.38 to 2.65; P<0.001), all-cause death (HR: 2.08; 95% CI: 1.28 to 3.38; P=0.003), all-cause readmission (HR: 2.67; 95% CI: 1.78 to 4.01; P<0.001), and HF readmission (HR: 2.11; 95% CI: 1.19 to 3.72; P=0.010). Prior ischemic stroke was associated with a significantly higher risk of all 4 outcomes at both 6 months and 1 year. CONCLUSIONS: Prior ischemic stroke was a potent and persistent risk predictor of death and readmission among patients with HF after accounting for clinical characteristics.


Assuntos
Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/mortalidade , AVC Isquêmico/complicações , Readmissão do Paciente , Pontuação de Propensão , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de Risco
16.
Fish Physiol Biochem ; 45(5): 1603-1614, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31054044

RESUMO

In order to study the effects of dietary fatty acid compositions on glucose metabolism, large yellow croaker juveniles Larimichthys crocea (initial weight, 36.80 ± 0.39 g) were fed with two experiment diets for 12 weeks. The two diets contained 6.5% of fish oil (FO) and palm oil (PO), respectively. Results showed that the contents of saturated fatty acids in liver and muscle, levels of glucose, triglyceride (TG), non-esterified fatty acid (NEFA), and leptin in blood were significantly higher in PO group, while the hepatic glycogen and muscle glycogen significantly decreased (P < 0.05). There were no significant differences in blood insulin and adiponectin levels between the two groups (P > 0.05). Compared with the FO group, the expressions of glucokinase (GK), glucose-6-phosphate dehydrogenase, glycogen synthase (GYS), glucose transporter 2 (GLUT2), insulin receptor 1 (IR1), insulin receptor substrate 1 (IRS1), insulin receptor substrate (IRS2), and protein kinase B (AKT2) were significantly decreased, and the expressions of phosphoenolpyruvate carboxykinase (PEPCK) in liver were significantly increased in the PO group. Meanwhile, the expressions of GK, phosphofructokinase, GYS, GLUT4, and insulin receptor 2 (IR2) were significantly reduced, and the expressions PEPCK, fructose-1 and 6-diphosphatase in muscle were significantly increased in the PO group. In conclusion, palm oil in diet could inhibit the utilization of glucose and promote the endogenous glucose production in large yellow croaker by reducing the sensitivity of insulin, so as to increase the blood glucose level.


Assuntos
Ração Animal/análise , Dieta/veterinária , Óleos de Peixe/farmacologia , Peixes/metabolismo , Glucose/metabolismo , Óleo de Palmeira/farmacologia , Fenômenos Fisiológicos da Nutrição Animal , Animais
17.
J Magn Reson Imaging ; 47(5): 1406-1414, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29044903

RESUMO

BACKGROUND: Both acute and chronic myocardial infarction (AMI and CMI, respectively) exhibit delayed enhancement; however, clinical decision-making processes frequently require the differentiation of these two types of myocardial injury. PURPOSE: To investigate the reliability of AMI and CMI characterization using native T1 mapping and its feasibility for discriminating AMI from CMI. STUDY TYPE: Case-control. ANIMAL MODEL: The study cohort comprised 12 AMI (mean post-MI, 3.75 ± 1.29 days) and 15 CMI (mean post-MI, 39.53 ± 6.10 days) Bama mini-pigs. FIELD STRENGTH/SEQUENCE: Balanced steady-state free precession (bSSFP), segmented-turbo-FLASH-PSIR, and modified Look-Locker inversion recovery (MOLLI) sequences at 3.0T. ASSESSMENT: The infarct sizes were compared on matching short-axis slices of late-gadolinium-enhanced (LGE) images and T1 maps by two experienced radiologists. STATISTICAL TESTS: The infarct sizes were compared on matching short-axis slices of LGE images and T1 maps, and agreement was determined using linear regression and Bland-Altman analyses. The native T1 values were compared between AMI and CMI models (independent sample t-test). The intraclass correlation coefficient was used to assess inter- and intraobserver variability. RESULTS: Measured infarct sizes did not differ between native T1 mapping and LGE images (AMI: P = 0.913; CMI: P = 0.233), and good agreement was observed between the two techniques (AMI: bias, -3.38 ± 19.38%; R2 = 0.96; CMI: bias, -10.55 ± 10.90%; R2 = 0.90). However, the native infarction myocardium T1 values and the T1 signal intensity ratio of infarct and remote myocardium (T1 SI ratio) did not differ significantly between AMI and CMI (P = 0.173). DATA CONCLUSION: Noncontrast native T1 mapping can accurately determine acute and chronic infarct areas as well as conventional LGE imaging; however, it cannot distinguish acute from chronic MI. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:1406-1414.


Assuntos
Imageamento por Ressonância Magnética , Infarto do Miocárdio/diagnóstico por imagem , Animais , Meios de Contraste , Tomada de Decisões , Sistemas de Apoio a Decisões Clínicas , Modelos Animais de Doenças , Gadolínio , Interpretação de Imagem Assistida por Computador/métodos , Modelos Lineares , Imagem Cinética por Ressonância Magnética , Miocárdio , Variações Dependentes do Observador , Radiologia/métodos , Análise de Regressão , Reprodutibilidade dos Testes , Suínos , Porco Miniatura , Temperatura
18.
Gen Comp Endocrinol ; 266: 9-20, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-29454596

RESUMO

The present study comparatively analyzed the blood glucose and insulin concentration, the temporal and spatial expression of brain-gut peptides and the key enzymes of glycolysis and gluconeogenesis in Japanese flounder by intraperitoneal injection (IP) and oral administration (OR) of glucose. Samples were collected at 0, 1, 3, 5, 7, 9, 12, 24 and 48 h after IP and OR glucose, respectively. Results showed that the hyperglycemia lasted for about 10 h and 21 h in OR and IP group, respectively. The serum insulin concentration significantly decreased at 3 h (1.58 ±â€¯0.21 mIU/L) after IP glucose. However, it significantly increased at 3 h (3.37 ±â€¯0.341 mIU/L) after OR glucose. The gene expressions of prosomatostatin, neuropeptide Y, cholecystokinin precursor and orexin precursor in the brain showed different profiles between the OR and IP group. The OR not IP administration of glucose had significant effects on the gene expressions of preprovasoactive intestinal peptide, pituitary adenylate cyclase activating polypeptide and gastrin in intestine. In conclusion, brain-gut peptides were confirmed in the present study. And the serum insulin and the brain-gut peptides have different responses between the IP and OR administration of glucose. The OR could stimulate the brain-gut peptide expressions, which have effects on the insulin secretion and then regulate the blood glucose levels. However, in IP group, there is little chance to stimulate brain-gut peptide expression to influence the insulin secretion, which leads to a longer hyperglycemia.


Assuntos
Encéfalo/metabolismo , Linguado/metabolismo , Trato Gastrointestinal/metabolismo , Glucose/administração & dosagem , Glucose/metabolismo , Homeostase/efeitos dos fármacos , Insulina/farmacologia , Peptídeos/metabolismo , Administração Oral , Animais , Glicemia/metabolismo , Regulação da Expressão Gênica , Gluconeogênese , Glicogênio/metabolismo , Injeções Intraperitoneais , Insulina/sangue , Fígado/enzimologia , Masculino , Músculos/metabolismo , Peptídeos/genética , Distribuição Tecidual
19.
Angew Chem Int Ed Engl ; 57(42): 13868-13872, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30151881

RESUMO

The development of group 15 Lewis acids is an area of active investigation that has led to numerous advances in anion sensing and catalysis. While phosphorus has drawn considerable attention, emerging research shows that organoantimony(III) reagents may also act as potent Lewis acids. Comparison of the properties of SbPh3 , Sb(C6 F5 )3 , and SbArF 3 with those of their tetrachlorocatecholate analogues SbPh3 Cat, Sb(C6 F5 )3 Cat, and SbArF 3 Cat (Cat=o-O2 C6 Cl4 , ArF =3,5-(CF3 )2 C6 H3 ) demonstrates that the Lewis acidity of electron deficient organoantimony(III) reagents can be readily enhanced by oxidation to the +V state-as verified by binding studies, organic reaction catalysis, and computational studies. The results are rationalized by explaining that oxidation of the antimony center leads to a lowering of the accepting σ* orbital and a deeper carving of the associated σ-hole.

20.
Arch Microbiol ; 199(3): 505-511, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27942773

RESUMO

Nitrite-dependent anaerobic methane oxidation (n-damo) process might be an important methane sink in wetland system. However, information on n-damo microorganisms in constructed wetland (CW) system for water treatment is still lacking. The present study investigated the n-damo communities in five full-scale vertical-flow CW systems with different plants. N-damo bacterial abundance did not show a considerable shift in CW planted with Cyperus papyrus, but varied greatly in other CW systems. However, the evident vertical change of n-damo community diversity occurred in each CW system. These CW systems displayed the different vertical change trends for either n-damo community abundance or diversity. In addition, CW n-damo community structure could change with wetland layer depth. At a given wetland layer depth, the evident difference of n-damo community abundance, diversity and structure could be observed in the five different CW systems. Both wetland layer depth and vegetation type could contribute to the shift of n-damo bacterial abundance and community structure in CWs.


Assuntos
Euryarchaeota/fisiologia , Fenômenos Fisiológicos Vegetais , Microbiologia do Solo , Purificação da Água , Áreas Alagadas , Anaerobiose , Biodiversidade , Euryarchaeota/classificação , Euryarchaeota/genética , Genes Bacterianos/genética , Nitritos/metabolismo , Oxirredução , Filogenia , Densidade Demográfica
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