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1.
Artigo em Inglês | MEDLINE | ID: mdl-38062624

RESUMO

Background: The fluid status and rate of blood flow through the arteriovenous fistula (AVF) are two important factors affecting hemodynamic in hemodialysis patients; however, their effects on pulmonary hypertension have rarely been studied. Hence, we aimed to evaluate the effects of these factors in hemodialysis patients with pulmonary hypertension. Methods: This single-center cross-sectional survey included 219 maintenance hemodialysis patients (139 [63.5%] male). The prevalence of pulmonary hypertension was 13.6% (30 of 219). Pulmonary artery pressure was measured by echocardiography, fluid status was measured objectively using bioimpedance spectroscopy, and blood flow rate in the AVF (Qa) was determined using Doppler ultrasound. Results: The overall mean overhydration before hemodialysis was 1.5 L (range, 0.6-2.8 L). The mean overhydration in patients with and without pulmonary hypertension was 3.6 L (range, 2.3-4.6 L) and 1.4 L (range, 0.6-2.4 L), respectively (p < 0.001). The overall mean Qa was 780 mL/min (range, 570-1,015.5 mL/min). The mean Qa of patients with and without pulmonary hypertension was 672 mL/min (range, 505.7-982.2 mL/min) and 790 mL/min (range, 591-1,026 mL/min), respectively (p = 0.27). Overhydration (odds ratio [OR], 1.46; 95% confidence interval [CI], 1.08-1.97; p = 0.01), N-terminal prohormone of brain natriuretic peptide (NT-proBNP; OR, 1.36; 95% CI, 1.09-1.71; p = 0.007), and left atrial diameter (OR, 1.14; 95% CI, 1.01-1.28; p = 0.03) were risk factors. Conclusion: Pulmonary hypertension is strongly associated with overhydration, NT-proBNP, and left atrial diameter in hemodialysis patients.

2.
Hypertens Res ; 46(10): 2378-2387, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37532950

RESUMO

Hypertension induces left atrial (LA) and left ventricular (LV) dysfunction, and an increase in arterial stiffness. This study aimed to investigate the associations of brachial-ankle pulse wave velocity (baPWV) with LA stiffness and LA phasic function in hypertension. A total of 305 hypertensive inpatients enrolled and were divided into two groups based on baPWV [Group I, baPWV ≤ 1515 (cm/s), n = 153; Group II, baPWV > 1515 (cm/s), n = 152]. Two-dimensional speckle tracking echocardiography (2D-STE) based LA phasic strains (LAS-S, LAS-E, LAS-A) and LV global longitudinal strain (LVGLS) were evaluated. LA stiffness index (LASI) was defined as the ratio of E/e' to LAS-S. Multivariate linear regression modeling was used to analyze the associations of baPWV with LASI and LA phasic function in all patients as well as age-specific and sex-specific subgroups. LASI was significantly higher in Group II [0.35(0.26, 0.52)] compared with Group I [0.26(0.20, 0.36)] (P < 0.001). After adjusting cardiovascular risk factors, medication, and LV structural and functional parameters (LVEF, LVMI, E/A ratio, and LVGLS), baPWV remained significantly correlated with LASI (P < 0.05). We also evaluated the predictive value of baPWV for LASI, the area under the curve (AUC) was 0.663 (95% CI: 0.607-0.716, P < 0.001). In conclusion, BaPWV was independently associated with LA stiffness in hypertensive inpatients. BaPWV also exhibited a certain predictive value for LA stiffness in these inpatients. Measuring arterial stiffness can provide clinicians clues for early cardiac target organ damage (TOD) in addition to vascular TOD.


Assuntos
Fibrilação Atrial , Hipertensão , Rigidez Vascular , Disfunção Ventricular Esquerda , Masculino , Feminino , Humanos , Índice Tornozelo-Braço , Pacientes Internados , Fibrilação Atrial/complicações , Análise de Onda de Pulso
3.
J Am Soc Echocardiogr ; 36(10): 1055-1063, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37225007

RESUMO

BACKGROUND: Predicting left ventricular recovery (LVR) after acute ST-segment elevation myocardial infarction (STEMI) is of prognostic importance. This study aims to explore the prognostic implications of segmental noninvasive myocardial work (MW) and microvascular perfusion (MVP) after STEMI. METHODS: In this retrospective study, 112 patients with STEMI who underwent primary percutaneous coronary intervention and transthoracic echocardiography after percutaneous coronary intervention were enrolled. Microvascular perfusion was analyzed by myocardial contrast echocardiography, and segmental MW was analyzed by noninvasive pressure-strain loops. A total of 671 segments with abnormal function at baseline were analyzed. The degrees of MVP were observed following intermittent high-mechanical index impulses: replenishment within 4 seconds (normal MVP), replenishment >4 seconds and within 10 seconds (delayed MVP), and persistent defect (microvascular obstruction). The correlation between MW and MVP was analyzed. The correlation of the MW and MVP with LVR (normalization of wall thickening, >25%) was assessed. The prognostic value of segmental MW and MVP for cardiac events (cardiac death, admission for congestive heart failure, or recurrent myocardial infarction) was evaluated. RESULTS: Normal MVP was seen in 70 segments, delayed MVP in 236, and microvascular obstruction in 365. The segmental MW indices were independently correlated with MVP; 244 (36.4%) segments had segmental LVR at 3-month follow-up. Segmental MW efficiency and MVP were independently associated with segmental LVR (P < .05). The χ2 of combination of segmental MW efficiency and MVP was higher than either index alone for identifying segmental LVR (P < .001). At a median follow-up of 42.0 months, cardiac events occurred in 13 patients; all regional MW parameters, high sensitivity troponin I, regional longitudinal strain, and so on were associated with cardiac events. CONCLUSIONS: Segmental MW indices are associated with MVP within the infarct zone following reperfused STEMI. Both are independently associated with segmental LVR, and regional MW is associated with cardiac events, providing prognostic value in STEMI patients.


Assuntos
Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Infarto do Miocárdio com Supradesnível do Segmento ST/complicações , Estudos Retrospectivos , Ecocardiografia , Prognóstico , Perfusão , Função Ventricular Esquerda
4.
Materials (Basel) ; 16(5)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36903090

RESUMO

Microalloyed steels have emerged to replace conventional plain-carbon steels to achieve longer wheel life on Chinese railroads. In this work, with the aim of preventing spalling, a mechanism that consists of ratcheting and shakedown theory correlated with steel properties is systematically investigated. Mechanical and ratcheting tests were carried out for microalloyed wheel steel to which vanadium was added in the range of 0-0.15 wt.% and the results were compared with that obtained for conventional plain-carbon wheel steel. The microstructure and precipitation were characterized via microscopy. As a result, the grain size was not obviously refined, and the pearlite lamellar spacing decreased from 148 nm to 131 nm in microalloyed wheel steel. Moreover, an increase in the number of vanadium carbide precipitates was observed, which were mainly dispersed and uneven, and precipitated in the pro-eutectoid ferrite region, in contrast to the observation of lower precipitation in the pearlite. It has been found that vanadium addition can lead to an increase in yield strength by precipitation strengthening, with no reduction or increase in tensile strength, elongation or hardness. The ratcheting strain rate for microalloyed wheel steel was determined to be lower than that for plain-carbon wheel steel via asymmetrical cyclic stressing tests. An increase in the pro-eutectoid ferrite content leads to beneficial wear, which can diminish spalling and surface-initiated RCF.

5.
Int J Gen Med ; 15: 7329-7339, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36157292

RESUMO

Purpose: Left atrial thrombus (LAT)/left atrial spontaneous echo contrast (LASEC) still exists in CHA2DS2-VASc score-defined low/borderline risk population. The purpose of this study is to explore the risk factors that associate with LAT/SEC and to create a nomogram to predict LAT/SEC risk in NVAF patients with low/borderline CHA2DS2-VASc scores. Patients and Methods: A total of 834 NVAF patients with complete data on transesophageal echocardiography (TEE) were included in this study. Univariate and multivariate logistic regression analyses were performed to identify the risk factors that associate with LAT/SEC, and a nomogram was established based on the results. Receiver operating characteristic curve (ROC), calibration curve and decision curve analysis were performed to verify the predictive power of nomogram. Results: The rates for LAT/SEC for the training and validation cohorts were 84 (14.7%) and 30 (11.4%), respectively. Independent factors including age, left ventricular ejection fraction (LVEF), left atrial diameter (LAD), smoke, non-paroxysmal AF (NPAF), and E/e' were considered to construct the nomogram for LAT/SEC. The AUC for nomogram was 0.839 and 0.811 in the training and validation cohorts, respectively. The calibration and decision curve analysis showed that the nomogram had a good prediction capacity and would be clinically useful. Conclusion: Age, LVEF, LAD, smoke, NPAF, and E/e' are independently associated with LAT/SEC in NVAF patients with low/borderline CHA2DS2-VASc scores. The nomogram that incorporates these six variables effectively predict LAT/SEC risk in NVAF patients with low/borderline CHA2DS2-VASc scores.

6.
Front Cardiovasc Med ; 9: 903323, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35722086

RESUMO

Background: Eosinophilic leukemia (EL) is a rare, serious and potentially life-threatening condition characterized by the overproduction of eosinophils leading to tissue eosinophilic infiltration and damage. Although multiple organ systems may be involved, progressive eosinophilic myocarditis (EM) is the most common cause of morbidity and mortality. Early diagnosis and follow-up surveillance combined with multimodal imaging are crucial for appropriate treatment of EM. Case Summary: It's a rare case of EL with EM and intracardiac thrombus in a 59-year-old patient who presented with asthenia for 3 weeks. Full blood count analysis indicated significant eosinophilia. Bone marrow aspirate revealed dysplastic eosinophilia and a FIP1L1-PDGFRA fusion gene (4q12) was detected, confirming EL. Echocardiography revealed EM with intracardiac thrombus. This was later confirmed by cardiac magnetic resonance imaging. The patient was commenced on imatinib and prednisolone and good clinical response was obtained. Through 18F-FAPI PET/CT imaging, we obtained in vivo visualization of fibroblast activation changes in the early stage of cardiac structure remodeling. With anti-fibrotic therapy after heart failure, the patient achieved a good clinical response. Conclusion: This case demonstrates in vivo visualization of fibroblast activation after EM. Multimodality imaging can provide early diagnosis and may guide tailored antifibrotic therapy in early stage of EM.

7.
Clin Cardiol ; 45(5): 540-548, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35294063

RESUMO

BACKGROUND: Left atrial (LA) function and mechanical dispersion changes in breast cancer patients treated with chemotherapy remain unclear. HYPOTHESIS: LA function and LA mechanical dispersion in breast cancer patients would be impaired after chemotherapy. METHODS: This single-center retrospective study included 91 consecutive breast cancer patients treated with chemotherapy and 30 controls. Patients were examined by echocardiography three times at intervals. Conventional parameters, left ventricular strain, LA strain, and LA mechanical dispersion were evaluated and compared. RESULTS: LA strain during reservoir phase (LASr), conduit phase (LAScd), and contraction phase (LASct) all decreased markedly after chemotherapy and were lower than those of the controls (all p < .01). The standard deviation of time to peak positive strain during LA reservoir phase corrected by R-R interval (LA SD-TPSr) was significantly increased after chemotherapy and was higher than that of the controls (p < .001). The change of LA function was expressed as Δ. Multivariate linear regression analyses showed that LAVIp (0.399, 95% confidence interval [CI]: 0.610, 1.756, p = .000) was independently associated with ΔLASr, LAPEF (-0.325, 95% CI: -45.123, -10.676, p = .002) and age (0.227, 95% CI: 0.021, 0.350, p = .027) were independently associated with ΔLAScd, and LAVImax (0.341, 95% CI: 0.192, 0.723, p = .001) was independently associated with ΔLASct. LAVImax (0.505, 95% CI: 0.000, 0.001, p = .039) and mitral E (-0.256, 95% CI: 0.000, 0.000, p = .024)were independently associated with ΔLA SD-TPSr. CONCLUSIONS: Mechanical function of LA declined after chemotherapy in breast cancer patients. With the decrease of LA mechanical function, LA mechanical dispersion assessed by two-dimensional speckle-tracking echocardiography increased significantly, and its clinical value needs to be further studied.


Assuntos
Função do Átrio Esquerdo , Neoplasias da Mama , Neoplasias da Mama/tratamento farmacológico , Ecocardiografia/métodos , Feminino , Átrios do Coração/diagnóstico por imagem , Ventrículos do Coração , Humanos , Estudos Retrospectivos
8.
Antioxid Redox Signal ; 37(1-3): 19-39, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35081742

RESUMO

Aims: Cancer patients treated with anthracyclines are susceptible to atrial fibrillation (AF), while the mechanisms remain unclear. Due to sudden and unpredictable features, prediction of anthracycline-induced AF at early phase is difficult. Clinically, we tested whether anthracycline-induced early atrial remodeling in patients could be detected by echocardiography. Experimentally, we investigated the mechanisms of doxorubicin-induced atrial remodeling and AF in mice, and the protective effects of dexrazoxane and antioxidants. Methods and Results: Postsurgery breast cancer patients with an anthracycline-containing or anthracycline exclusion regimen were recruited for echocardiography before chemotherapy, and 3 and 6 months after chemotherapy. Mice were injected with doxorubicin or vehicle (5 mg/kg/week, 4 weeks), and left atrial diameter, electrical transmission, and AF inducibility were measured. Meanwhile, the level of reactive oxygen species (ROS), activity of antioxidant enzymes, cardiomyocyte size, vacuolization, inflammation, and fibrosis were also measured in mouse atria. The therapeutic effects of dexrazoxane and antioxidants on doxorubicin-induced changes in the aforementioned parameters were also determined. While ventricular parameters and functions were unchanged in cancer patients receiving anthracyclines before and after chemotherapy, left atrial reservoir and conduit function were decreased at 3 months postchemotherapy versus prechemotherapy. Doxorubicin-induced susceptibility to AF occurred in mice before onset of ventricular dysfunction. Doxorubicin-induced AF was via inducing structural remodeling (cardiomyocyte death, hypotrophy, and vacuolization) and electrical remodeling (reduction and redistribution of connexin 43) in atria, which was effectively prevented by dexrazoxane or antioxidants through inhibiting ROS generation or enhancing ROS elimination. Innovation and Conclusion: AF inducibility was induced after doxorubicin injection, which can be inhibited by repressing the ROS level. Antioxid. Redox Signal. 37, 19-39. The Clinical Trial Registration number is PJ-KS-KY-2019-73.


Assuntos
Fibrilação Atrial , Remodelamento Atrial , Neoplasias da Mama , Dexrazoxano , Animais , Antraciclinas/efeitos adversos , Antibióticos Antineoplásicos/efeitos adversos , Antioxidantes/uso terapêutico , Fibrilação Atrial/induzido quimicamente , Fibrilação Atrial/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Cardiotoxicidade/etiologia , Dexrazoxano/farmacologia , Dexrazoxano/uso terapêutico , Doxorrubicina , Feminino , Humanos , Camundongos , Espécies Reativas de Oxigênio
9.
Front Cardiovasc Med ; 8: 737551, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34722669

RESUMO

Background: The predictive power of the CHADS2 and CHA2DS2-VASc scores for the presence of Left atrial thrombus (LAT)/ spontaneous echo contrast (SEC) in non-valvular atrial fibrillation (NVAF) is modest. The aim of this analysis is to define clinical and ultrasonic variables associated with LAT/SEC and to propose nomograms for individual risk prediction. Methods: Data on 1,813 consecutive NVAF patients who underwent transesophageal echocardiography (TEE) from January 2016 to January 2021 were collected. The univariate and multivariate logistic regression analyses were used to construct a nomogram. We examined the predictive ability of the risk scores by calculating the area under the curve (AUC). Moreover, the performance of the nomogram was assessed with respect to calibration, discrimination, and clinical usefulness. Results: LAT/SEC was found in 260 (21.0%) and 124 (21.6%) patients in the training and validation cohorts, respectively. On multivariate analysis, independent factors for LAT/SEC were Age, left atrial diameter (LAD), left ventricular ejection fraction (LVEF), hypertension (HTN), previous stroke or transient ischemic attack, Non-paroxysmal AF and a nomogram was built based on these variables. The calibration curve for the probability of LAT/SEC showed good prediction agreement with actual observation. The nomogram achieved good concordance indexes of 0.836 and 0.794 in predicting LAT/SEC in the training and validation cohorts, respectively. Decision curve analysis demonstrated that the nomogram would be clinically useful. Conclusions: In this study, a nomogram was constructed that incorporated six characteristics of NVAF patients. The nomogram may be of great value for the prediction of LAT/SEC in NVAF patients.

10.
J Hypertens ; 39(11): 2318-2324, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34620813

RESUMO

OBJECTIVE: We examined the associations among the circadian rhythms of blood pressure (BP), heart rate (HR) and left atrial function in essential hypertensive patients. METHODS: The study included 237 essential hypertensive patients who completed 24-h ambulatory BP, HR monitoring and two-dimensional speckle tracking echocardiography (2DSTE). The strain and strain rate images were studied, and the following parameters were measured: left atrial reservoir strain and strain rate (LAS-S and LASR-S), left atrial conduit strain and strain rate (LAS-E and LASR-E), and left atrial booster strain and strain rate (LAS-A and LASR-A). The left atrial stiffness index (LASI) was identified as the ratio of E/e' to LAS-S. All participants were divided into three groups according to the percentage of nocturnal BP dipping (dippers, nondippers and reverse dippers). RESULTS: The LASI was significantly higher in BP reverse dippers than in dippers and nondippers. LAS-S, LAS-E and LASR-E were significantly lower in BP reverse dippers than dippers and nondippers. Multivariate logistic regression analysis demonstrated that age, night-time mean SBP and the percentage of nocturnal HR decline were independently related to an increased LASI. CONCLUSION: Impairment of the left atrial reservoir and conduit functions was correlated with abnormal BP and HR circadian rhythms in hypertension. Increased left atrial stiffness was associated with night-time SBP and the percentage of nocturnal HR decline.


Assuntos
Função do Átrio Esquerdo , Hipertensão , Pressão Sanguínea , Monitorização Ambulatorial da Pressão Arterial , Ritmo Circadiano , Frequência Cardíaca , Humanos
11.
BMC Neurosci ; 22(1): 18, 2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33752606

RESUMO

BACKGROUND: The SCN11A gene, encoded Nav1.9 TTX resistant sodium channels, is a main effector in peripheral inflammation related pain in nociceptive neurons. The role of SCN11A gene in the auditory system has not been well characterized. We therefore examined the expression of SCN11A in the murine cochlea, the morphological and physiological features of Nav1.9 knockout (KO) ICR mice. RESULTS: Nav1.9 expression was found in the primary afferent endings beneath the inner hair cells (IHCs). The relative quantitative expression of Nav1.9 mRNA in modiolus of wild-type (WT) mice remains unchanged from P0 to P60. The number of presynaptic CtBP2 puncta in Nav1.9 KO mice was significantly lower than WT. In addition, the number of SGNs in Nav1.9 KO mice was also less than WT in the basal turn, but not in the apical and middle turns. There was no lesion in the somas and stereocilia of hair cells in Nav1.9 KO mice. Furthermore, Nav1.9 KO mice showed higher and progressive elevated ABR threshold at 16 kHz, and a significant increase in CAP thresholds. CONCLUSIONS: These data suggest a role of Nav1.9 in regulating the function of ribbon synapses and the auditory nerves. The impairment induced by Nav1.9 gene deletion mimics the characters of cochlear synaptopathy.


Assuntos
Nervo Coclear/patologia , Perda Auditiva Neurossensorial/genética , Canal de Sódio Disparado por Voltagem NAV1.9/genética , Sinapses/patologia , Animais , Nervo Coclear/metabolismo , Deleção de Genes , Células Ciliadas Auditivas Internas/metabolismo , Células Ciliadas Auditivas Internas/patologia , Perda Auditiva Neurossensorial/metabolismo , Perda Auditiva Neurossensorial/patologia , Camundongos , Camundongos Endogâmicos ICR , Camundongos Knockout , Sinapses/metabolismo
12.
Comput Intell Neurosci ; 2021: 6636150, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33510776

RESUMO

With the rapid development of big data, big data research in the security protection industry has been increasingly regarded as a hot spot. This article mainly aims at solving the problem of predicting the tendency of juvenile delinquency based on the experimental data of juvenile blindly following psychological crime. To solve this problem, this paper proposes a rough ant colony classification algorithm, referred to as RoughAC, which first uses the concept of upper and lower approximate sets in rough sets to determine the degree of membership. In addition, in the ant colony algorithm, we use the membership value to update the pheromone. Experiments show that the algorithm can not only solve the premature convergence problem caused by stagnation near the local optimal solution but also solve the continuous domain and combinatorial optimization problems and achieve better classification results. Moreover, the algorithm has a good effect on predicting classification and can provide guidance for predicting the tendency of juvenile delinquency.


Assuntos
Algoritmos , Psicologia do Adolescente , Adolescente , Humanos , Feromônios
13.
Hypertens Res ; 44(3): 299-309, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32917967

RESUMO

This study aimed to evaluate left atrial (LA) mechanics using two-dimensional speckle-tracking echocardiography (2DSTE) and investigate their correlations with measures of target organ damage (TOD) in hypertension. We enrolled 42 healthy controls (Group I) and 286 hypertension patients: Group II (n = 79) had an LA volume index (LAVI) <28 ml/m2; Group III (n = 92) had an LAVI ≥28 ml/m2; and Group IV (n = 115) had hypertension with left ventricular hypertrophy (LVH). We measured the following parameters: LA reservoir strain and strain rate (LAS-S, LASR-S), LA conduit strain and strain rate (LAS-E and LASR-E), and LA booster strain and strain rate (LAS-A and LASR-A). The LA stiffness index (LASI) was defined as the ratio of early diastolic transmitral flow velocity/lateral mitral annulus myocardial velocity (E/e') to LAS-S. We performed correlation and regression analyses of individual TOD with LA phasic functions, the LASI, and cardiovascular risk factors. Our findings showed that there was a trend toward a gradual increase in the LASI from controls to normal LA and enlarged LA patients and finally to hypertrophic LV patients. The LASI was significantly higher in Group III [0.28 (0.20, 0.38)] than in Group I [0.20 (0.16, 0.23)] and Group II [0.22 (0.18, 0.27)] and was the highest in Group IV [0.33 (0.26, 0.43)]. The LA reservoir and conduit function gradually decreased from Group I to Group IV. Multivariate regression analysis revealed that the LASI was independently correlated with individual TOD. In conclusion, abnormal LA mechanics precede LA enlargement and LVH, and an increased LASI can be used as a marker of early TOD in hypertension.


Assuntos
Função do Átrio Esquerdo , Hipertensão , Rigidez Vascular , Função do Átrio Esquerdo/fisiologia , Estudos de Casos e Controles , Ecocardiografia , Humanos , Hipertensão/diagnóstico por imagem , Hipertensão/fisiopatologia , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/fisiopatologia , Rigidez Vascular/fisiologia
14.
Zool Res ; 41(5): 564-568, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32738109

RESUMO

Osteonecrosis is a common human disease in orthopedics. It is difficult to treat, and half of patients may need artificial joint replacement, resulting in a considerable economic burden and a reduction in quality of life. Hormones are one of the major causes of osteonecrosis and high doses of corticosteroids are considered the most dangerous factor. Because of the complexity of treatment, we still need a better animal model that can be widely used in drug development and testing. Tree shrews are more closely related to primates than rodents. As such, we constructed a successful tree shrew model to establish and evaluate steroid-associated osteonecrosis (SAON). We found that low-dose lipopolysaccharide (LPS) combined with high-dose methylprednisolone (MPS) over 12 weeks could be used to establish a tree shrew model with femoral head necrosis. Serum biochemical and histological analyses showed that an ideal model was obtained. Thus, this work provides a useful animal model for the study of SAON and for the optimization of treatment methods.


Assuntos
Lipopolissacarídeos/toxicidade , Metilprednisolona/toxicidade , Osteonecrose/induzido quimicamente , Tupaiidae , Corticosteroides , Animais , Modelos Animais de Doenças , Glucocorticoides/administração & dosagem , Glucocorticoides/toxicidade , Lipopolissacarídeos/administração & dosagem , Metilprednisolona/administração & dosagem
15.
Hypertens Res ; 43(10): 1089-1098, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32541849

RESUMO

Cardiac remodeling is an important pathological process ultimately leading to heart failure. Ubiquitin carboxy-terminal hydrolase 1 (UCHL1) is a deubiquitinase that plays a critical role in neurodegenerative diseases and cancer. However, its role in cardiac remodeling in spontaneously hypertensive rats remains unclear. Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHRs) were administered the UCHL1 inhibitor LDN-57444 (20 µg/kg/day) from 2 months of age for 4 months. Blood pressure, cardiac hypertrophy, fibrosis, inflammation, and oxidative stress were evaluated by the tail-cuff system, echocardiography, and histological analysis. Gene and protein expression levels were examined by real-time PCR and immunoblotting analysis. At 6 months of age, the expression of UCHL at the mRNA and protein levels was significantly upregulated in SHRs compared with WKYs. Moreover, systolic blood pressure, cardiac performance, left ventricular (LV) hypertrophy, fibrosis, inflammation, and superoxide production were significantly increased in SHRs compared with WKYs, and these effects were markedly attenuated by LDN-57444 after 4 months of administration. These beneficial actions were possibly associated with a reduction in blood pressure and inactivation of multiple signaling pathways, including AKT, ERK1/2, STAT3, calcineurin A, TGF-ß/Smad2/3, and NF-κB. In conclusion, the results indicate that UCHL1 is involved in hypertensive cardiac remodeling in SHRs, and targeting UCHL1 activity may be a novel potential therapeutic approach for the treatment of hypertensive heart diseases.


Assuntos
Cardiomegalia/prevenção & controle , Hipertensão/tratamento farmacológico , Indóis/uso terapêutico , Oximas/uso terapêutico , Ubiquitina Tiolesterase/antagonistas & inibidores , Animais , Pressão Sanguínea/efeitos dos fármacos , Cardiomegalia/etiologia , Avaliação Pré-Clínica de Medicamentos , Hipertensão/complicações , Hipertensão/metabolismo , Indóis/farmacologia , Miocárdio/enzimologia , Estresse Oxidativo/efeitos dos fármacos , Oximas/farmacologia , PTEN Fosfo-Hidrolase/metabolismo , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Transdução de Sinais/efeitos dos fármacos , Ubiquitina Tiolesterase/metabolismo
16.
Echocardiography ; 36(3): 537-545, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30735281

RESUMO

OBJECTIVE: The aim of this study was to investigate the value of real time three-dimensional transesophageal echocardiography (RT3DTEE) in percutaneous closure of the left atrial appendage (LAAC). In addition, this study also explored the change in the size of the left atrial appendage (LAA) from 24 hours before the operation to just before implantation during the operation. METHODS AND RESULTS: In a retrospective study, 32 patients underwent two-dimensional transesophageal echocardiography (2DTEE) and RT3DTEE 24 hours prior to operation and during operation. The maximal LAA orifice diameter (by 2DTEE, 22.7 ± 2.7 vs 24.6 ± 2.2 mm, P < 0.01; by RT3DTEE, 24.2 ± 2.9 vs 25.8 ± 2.7 mm, P < 0.01), the maximal landing zone diameter (by 2DTEE, 19.0 ± 2.8 vs 20.4 ± 2.8 mm, P < 0.01; by RT3DTEE, 20.4 ± 2.7 vs 22.6 ± 3.0 mm, P < 0.01), and the maximal depth diameter (by 2DTEE, 25.2 ± 3.2 vs 26.5 ± 3.0 mm, P < 0.01; by RT3DTEE, 26.4 ± 3.2 vs 27.5 ± 3.7 mm, P < 0.01) all increased significantly during the operation. The highest correlation (R) between the maximal landing zone diameter and the compressed occluder diameter was determined for RT3DTEE measurements during the operation (R = 0.90), whereas the landing zone diameter (R = 0.80) measured by 2DTEE was less correlated. In addition, our study showed that RT3DTEE was of great value in discriminating the LAA orifice shape, allowing differentiation of the LAA morphology and identification of the number of LAA lobes. CONCLUSIONS: A certain amount of intravenous rehydration just before and during operation increased the LAA size significantly. The measurements by RT3DTEE showed a closer correlation to LAA occluder size than those by 2DTEE. The LAA displayed by RT3DTEE was more visible than that by 2DTEE.


Assuntos
Apêndice Atrial/diagnóstico por imagem , Apêndice Atrial/cirurgia , Ecocardiografia Tridimensional/métodos , Ecocardiografia Transesofagiana/métodos , Cuidados Intraoperatórios/métodos , Cuidados Pré-Operatórios/métodos , Idoso , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Estudos Retrospectivos , Dispositivo para Oclusão Septal , Índice de Gravidade de Doença
17.
Chin Med J (Engl) ; 132(3): 285-293, 2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30681494

RESUMO

BACKGROUND: Pulmonary vein (PV) occlusion generally depends on repetitive contrast agent injection when cryoballoon ablation for atrial fibrillation (AF). The present study was to compare the effect of cryoballoon ablation for AF guided by transesophageal echocardiography (TEE) vs. contrast agent injection. METHODS: Eighty patients with paroxysmal AF (PAF) were enrolled in the study. About 40 patients underwent cryoballoon ablation without TEE (non-TEE group) and the other 40 underwent cryoballoon ablation with TEE for PV occlusion (TEE group). In the TEE group during the procedure, PVs were displayed in 3-dimensional images to guide the balloon to achieve PV occlusion. The patients were followed up at regularly scheduled visits every 2 months. RESULTS: No differences were identified between the groups in regard to the procedure time and cryoablation time for each PV. The fluoroscopy time (6.7 ±â€Š4.2 min vs. 17.9 ±â€Š5.9 min, P < 0.05) and the amount of contrast agent (3.0 ±â€Š5.1 mL vs.18.1 ±â€Š3.4 mL, P < 0.05) in the TEE group were both less than the non-TEE group. At a mean of 13.0 ±â€Š3.3 mon follow-up, success rates were similar between the TEE group and non-TEE group (77.5% vs. 80.0%, P = 0.88). CONCLUSIONS: Cryoballoon ablation with TEE for occlusion of the PV is both safe and effective. Less fluoroscopy time and a lower contrast agent load can be achieved with the help of TEE for PV occlusion during procedure.


Assuntos
Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Criocirurgia/métodos , Ecocardiografia Tridimensional/métodos , Ecocardiografia Transesofagiana/métodos , Idoso , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Veias Pulmonares/diagnóstico por imagem , Veias Pulmonares/cirurgia , Resultado do Tratamento
18.
Cardiovasc Ultrasound ; 16(1): 13, 2018 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-30126422

RESUMO

BACKGROUND: Atrial fibrillation (AF) can result in atrial functional mitral regurgitation (MR), but the mechanism remains controversial. Few data about the relationship between the 3-dimensional morphology of the MV and the degree of MR in AF exist. METHODS: Real-time 3-dimensional transesophageal echocardiography (3D-TEE) of the MV was acquired in 168 patients with AF (57.7% persistent AF), including 25 (14.9%) patients with moderate to severe MR (the MR+ group) and 25 patients without AF as controls. The 3-dimensional geometry of the MV apparatus was acquired using dedicated quantification software. RESULTS: Compared with the group of patients with no or mild MR (the MR- group) and the controls, the MR+ group had a larger left atrium (LA), a more dilated mitral annulus (MA), a reduced annular height to commissural width ratio (AHCWR), indicating flattening of the annular saddle shape, and greater leaflet surfaces and tethering. MR severity was correlated with the MA area (r2 = 0.43, P < 0.01) and the annulus circumference (r2 = 0.38, P < 0.01). A logistic regression analysis indicated that the MA area (OR: 1.02, 95% CI: 1.01-1.03, P < 0.01), AHCWR (OR: 0.24, 95% CI: 0.14-0.35, P = 0.04) and MV tenting volume (OR: 3.24, 95% CI: 1.16-9.08, P = 0.03) were independent predictors of MR severity in AF patients. CONCLUSIONS: The mechanisms of "atrial functional MR" are complex and include dilation of the MA, flattening of the annular saddle shape and greater leaflet tethering.


Assuntos
Função do Átrio Esquerdo/fisiologia , Ecocardiografia Tridimensional/métodos , Ecocardiografia Transesofagiana/métodos , Átrios do Coração/diagnóstico por imagem , Insuficiência da Valva Mitral/diagnóstico , Valva Mitral/diagnóstico por imagem , Idoso , Feminino , Átrios do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/fisiopatologia , Insuficiência da Valva Mitral/fisiopatologia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença
19.
Int J Cardiovasc Imaging ; 34(7): 1147-1154, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29460124

RESUMO

To investigate the capacity of biphasic cardiac CT (CCT) for qualitative and quantitative evaluation of different grades of left atrial appendage spontaneous echo contrast (LAASEC). The study included 267 inpatients with confirmed atrial fibrillation who underwent both CCT and transesophageal echocardiography (TEE). CT numbers for LAA, ascending aorta (AA), and left atrium (LA) were identified, and ROC curves for LAA, LAA/AA, and LAA/LA were plotted. With TEE as the standard, the sensitivity, specificity, PPV, NPV, and accuracy of CCT for LAASEC grade ≥ 1 were 60.3, 92.9, 92.4, 64.8, and 75.7%; and for grade ≥ 2 were 100.0, 84.4, 71.4, 100.0, and 88.8% respectively. The values of LAA, LAA/AA, and LAA/LA were significantly larger in LAASEC grade 0 versus 1 and in grade 1 versus 2, but were similar in grades 2 and 3 or in grades 3 and 4. The values of LAA/AA were larger in grade 2 versus 4. When the cutoff value for LAA/AA = 0.897, sensitivity, specificity, PPV, NPV, and accuracy of CCT for LAASEC grade ≥ 1 was 89.6, 83.2, 87.9, 85.5, and 86.9% and with a cutoff for LAA/AA of 0.524, the sensitivity, specificity, PPV, NPV, and accuracy for LAASEC grade ≥ 2 was 98.7, 92.7, 84.1, 99.4, and 94.4%. Although CCT showed limited diagnostic accuracy for grade 1 LAASEC, grade ≥ 2 LAASEC could be excluded when there was no LAA filling defect on first-phase CCT, and TEE can be avoided. CCT has an excellent accuracy in diagnosing LAASEC, and quantitative analysis (in particular LAA/AA) is superior.


Assuntos
Apêndice Atrial/diagnóstico por imagem , Fibrilação Atrial/diagnóstico por imagem , Ecocardiografia Transesofagiana , Cardiopatias/diagnóstico por imagem , Trombose/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas de Imagem Cardíaca , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
20.
Echocardiography ; 34(2): 176-183, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28240425

RESUMO

BACKGROUND: The aim of this study was to investigate left atrial (LA) function and synchrony in paroxysmal atrial fibrillation (PAF) patients using two-dimensional speckle tracking echocardiography (STE). METHODS: Forty-five PAF patients and 30 healthy controls were enrolled. LA peak ventricular systolic longitudinal strain (LAS-S ) and strain rate (LASR-S ) and left atrial longitudinal strain (LAS-A ) and strain rate (LASR-A ) during late diastole were determined using STE, and the standard deviation of the time to peak (TPSD) of the regional strains was calculated to quantify LA dyssynchrony. TPSD during ventricular systole and late diastole were named SDs and SDa, respectively. RESULTS: Left atrial peak longitudinal strain during ventricular systole (LAS-S ) (29.34±8.57 vs 36.73±6.13), LASR-S (1.27±0.311 vs 1.57±0.25), LAS-A (13.11±4.91 vs 17.86±3.57), and LASR-A (-1.51±0.58 vs -1.90±0.30) were reduced in the PAF group compared with the controls (P<.05 for all). SDs (8.11±3.00% vs 4.67±1.48%) and SDa (5.57±2.26% vs 3.11±1.13%) were greater in PAF patients than in the controls (P<.05 for both). Furthermore, PAF patients with normal LA sizes exhibited lower LAS-S (P<.05), LASR-S (P<.05), LAS-A (P<.05), and LASR-A (P<.05) values and increased SDs (P<.05) and SDa (P<.05) values compared with the controls. Multivariate regression confirmed that SDs and SDa were powerful parameters for differentiating PAF patients from controls (SDs: sensitivity, 83%; specificity, 72%; SDa: sensitivity, 81%; specificity, 76%). CONCLUSIONS: Left atrial (LA) dysfunction and dyssynchrony in PAF patients can be detected with STE even in the absence of LA enlargement. STE-derived SDs and SDa were powerful parameters for identifying PAF patients.


Assuntos
Fibrilação Atrial/fisiopatologia , Função do Átrio Esquerdo/fisiologia , Ecocardiografia/métodos , Feminino , Átrios do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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