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1.
J Food Sci ; 88(11): 4574-4590, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37850398

RESUMO

Browning discoloration is a critical issue that negatively affects the quality of fresh-cut products and their industrial growth. Although many individual anti-browning technologies have been adopted, very few reports on the combination use of natural product extracts and physical methods exist. This study investigated the use of Flos Sophorae Immaturus extract in conjunction with thermal treatment and discovered that the combination effectively retarded browning in fresh-cut potatoes. Accordingly, the activities of polyphenol oxidase, peroxidase, and phenylalanine ammonia-lyase, as well as phenol accumulation, were effectively regulated. Meanwhile, this combination treatment also allowed for the modulation of nitric oxide synthase, superoxide dismutase, and catalase activities, while also regulating the concentrations of nitric oxide, superoxide anion, and hydrogen peroxide. Furthermore, the duplex treatment also regulated the antioxidant capacity and malondialdehyde concentrations. In addition, 39 phytoactive compounds, including protocatechuic acid, quercetin, (-)-alpha-pinene, and matrine, were identified in the extract, which may function as the anti-browning composition. These findings suggest that the combination technology modulated the dynamic equilibrium of production and clearance of nitric oxide and reactive oxygen species, thereby reducing browning deterioration. This is, to our knowledge, the first report of the combined application of Flos Sophorae Immaturus and thermal treatment, which may offer a novel option for fresh-cut preservation. PRACTICAL APPLICATION: The feasibility of integrating a novel highly efficient, safe, environmentally friendly, and easy-to-operate anti-browning alternative, with the ability to integrate into the existing processing line was investigated. The color of sliced potato chips was significantly improved (73.4%) by dipping them in a 0.01% Flos Sophorae Immaturus solution for 5 min and then in 55°C water for 2 min. In this regard, superior browning alleviation may depend on the regulation of the browning reaction and the NO-ROS network. This method has a promising future for making fresh-cut products more appealing to consumers and may provide guidance for fresh-cut producers and related industries.


Assuntos
Óxido Nítrico , Solanum tuberosum , Espécies Reativas de Oxigênio , Quercetina , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia
2.
Food Res Int ; 167: 112709, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37087271

RESUMO

Fresh walnuts have a high water content and are susceptible to decay, and controlling fungal contamination during storage is vital to walnut marketing. In this research, the dominant pathogenic fungus of fresh walnuts was first identified as Penicillium crustosum by morphological and molecular methods. The antifungal effect of herbal smoke fumigation was tested in vitro and in vivo, including Myristica fragrans Houtt., Aucklandia lappa Decne., Eugenia caryophyllata Thunb., Atractylodes lancea (Thunb.) DC., Shiraia bambusicola Henn., Artemisia argyi Lévl. et Vant. The results demonstrated that smoke from all six herbs successfully inhibited P. crustosum growth, and A. argyi smoke produced the best antifungal effect, which contained higher contents of phenol (17.1%), eugenol (13.7%), hexacosane, tetracontane, heneicosane, linolenic acid and other antimicrobial components by gas chromatography-mass spectrometry. Interestingly, optical transmittance data were found to correlate with antifungal capacity, revealing that a formed physical barrier combined with the above antimicrobial compositions, to participate in mold controlling together. Finally, fumigation with A. argyi smoke was tested in a real storage situation at proper dose, which not only dramatically controlled fungal contamination (>70%), but also maintained better odor and taste without oxidative rancidity or other adverse effects. This is the first report in which herbal smoke fumigation was adopted to preserve fresh walnut, providing a new way to reduce mold contamination and maintain quality of fresh walnuts in a natural and safe manner. More research on the application of herbal smoke fumigation to agricultural products in post-harvest storage is needed to explore the conditions and products for which it can be used successfully.


Assuntos
Anti-Infecciosos , Juglans , Antifúngicos/farmacologia , Fumigação , Fumaça
3.
Animals (Basel) ; 10(3)2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32183166

RESUMO

The vertnin (VRTN) gene g.20311_20312ins291 was reported as an important variant related to the number of ribs (RIB), and the ins/ins genotype was advantageous for improving RIB of Western pigs. The purpose of this study was to determine whether the VRTN gene g.20311_20312ins291 influences RIB, carcass traits, and body size traits, including cannon bone circumference (CBC) in Chinese Suhuai pigs. We found that the VRTN gene g.20311_20312ins291 was polymorphic in Suhuai fattening pigs and gilts. The polymorphism of g.20311_20312ins291 was significantly associated with RIB and CDL in Suhuai fattening pigs (p < 0.01), whereas this variant had no influence on carcass weight (CWT). There was a tendency of association between this variant and carcass straight length (CSL) in Suhuai fattening pigs (p = 0.06). The polymorphism of g.20311_20312ins291 was also significantly associated with CBC in Suhuai gilts (p = 0.04). Furthermore, CBC was positively genetically correlated with body length (0.22, p < 0.01) and body weight (0.15, p < 0.01). Our results indicated that the VRTN gene g.20311_20312ins291 could be used as a potential marker for improving RIB, CDL, and CBC in Suhuai pigs.

4.
Childs Nerv Syst ; 31(9): 1493-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25976865

RESUMO

PURPOSE: The diagnosis and management of pediatric cerebrospinal fluid (CSF) leak and encephalocele are challenging. The current study aimed to identify patient characteristics, review operative techniques, and evaluate the efficacy and safety of endoscopic endonasal repair in a pediatric population. METHODS: We retrospectively reviewed the records of pediatric patients who underwent transnasal endoscopic repair of CSF leak with or without a meningocele or an encephalocele at Beijing Tongren Hospital, Capital Medical University, between July 2003 and May 2014. All patients had preoperative radiological evaluations and underwent endoscopic endonasal repair of their skull base defects. RESULTS: Altogether, 23 children (mean age 7.0 years) underwent the procedures. Sixteen cases were congenital, and 7 patients had trauma history. The herniations or defects included meningoencephaloceles in 15 cases, meningoceles in 4 cases, and CSF leak in 4 cases (2 patients had bilateral leaks). The leak or herniation sites were ethmoid roof in 10 patients (one was bilateral), cribriform plate in 5, lateral to the foramen cecum in 3, posterior wall of the frontal sinus in 1, sphenoid sinus in 2, lateral recess of the sphenoid sinus in 1, and sella turcica base in 2. All subjects had favorable clinical outcomes without recurrence during a follow-up of 6-123 months (mean 61.1 months). CONCLUSIONS: The endoscopic endonasal approach was the preferred method for repairing CSF leaks with or without an encephalocele in pediatric patients. Compared to traditional operations, this endoscopic procedure is minimally invasive, efficient, and safe.


Assuntos
Vazamento de Líquido Cefalorraquidiano/complicações , Vazamento de Líquido Cefalorraquidiano/cirurgia , Encefalocele/complicações , Encefalocele/cirurgia , Endoscopia/métodos , Seio Esfenoidal/cirurgia , Adolescente , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Estudos Retrospectivos , Tomógrafos Computadorizados , Cicatrização
5.
Crit Care ; 19: 68, 2015 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-25887895

RESUMO

INTRODUCTION: Differential hypoxia is a pivotal problem in patients with femoral veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) support. Despite recognition of differential hypoxia and attempts to deliver more oxygenated blood to the upper body, the mechanism of differential hypoxia as well as prevention strategies have not been well investigated. METHODS: We used a sheep model of acute respiratory failure that was supported with femoral VA ECMO from the inferior vena cava to the femoral artery (IVC-FA), ECMO from the superior vena cava to the FA (SVC-FA), ECMO from the IVC to the carotid artery (IVC-CA) and ECMO with an additional return cannula to the internal jugular vein based on the femoral VA ECMO (FA-IJV). Angiography and blood gas analyses were performed. RESULTS: With IVC-FA, blood oxygen saturation (SO2) of the IVC (83.6 ± 0.8%) was higher than that of the SVC (40.3 ± 1.0%). Oxygen-rich blood was drained back to the ECMO circuit and poorly oxygenated blood in the SVC entered the right atrium (RA). SVC-FA achieved oxygen-rich blood return from the IVC to the RA without shifting the arterial cannulation. Subsequently, SO2 of the SVC and the pulmonary artery increased (70.4 ± 1.0% and 73.4 ± 1.1%, respectively). Compared with IVC-FA, a lesser difference in venous oxygen return and attenuated differential hypoxia were observed with IVC-CA and FA-IJV. CONCLUSIONS: Differential venous oxygen return is a key factor in the etiology of differential hypoxia in VA ECMO. With knowledge of this mechanism, we can apply better cannula configurations in clinical practice.


Assuntos
Oxigenação por Membrana Extracorpórea/métodos , Oxigênio/sangue , Fluxo Sanguíneo Regional/fisiologia , Animais , Aortografia , Artérias Carótidas/fisiologia , Cateterismo/métodos , Modelos Animais de Doenças , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/fisiologia , Insuficiência Respiratória/terapia , Ovinos , Veia Cava Inferior/diagnóstico por imagem , Veia Cava Inferior/fisiologia , Veia Cava Superior/diagnóstico por imagem , Veia Cava Superior/fisiologia
6.
PLoS One ; 8(3): e58494, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23516490

RESUMO

OBJECTIVES: We sought to determine the feasibility and reproducibility of real-time 3-dimensional echocardiography (RT3DE) for evaluation of cardiac volume, mass, and function and to characterize maturational changes of these measurements in human fetuses. METHODS: Eighty pregnant women in the 2(nd) and 3(rd) trimesters (59 with normal fetuses and 21 with fetuses with congenital heart disease [CHD]) were enrolled. We acquired RT3DE images using a matrix-array transducer. RT3DE measurements of volume, mass, stroke volume (SV), combined cardiac output (CCO), and ejection fraction (EF) were obtained. Images were scored and analyzed by two blinded independent observers. Inter- and intraobserver variabilities and correlations between fetal cardiac indices and gestational age were determined. RESULTS: Fifty-two of 59 normal data sets (88%) and 9 of 21 CHD data sets (43%) were feasible for analysis. In normal fetuses, the right ventricle (RV) is larger than the left ventricle (LV) (P<0.05), but no difference exists between the LV and RV in mass, SV, CO, and CO/CCO. The EFs for the LV and RV were diminished; the RVSV/LVSV was reduced in CHD fetuses compared with normal fetuses (P<0.05). Fetal ventricular volumes, mass, SV, and CCO fit best into exponential curves with gestational age, but LVEF, RVEF, and RVSV/LVSV remain relatively constant. CONCLUSIONS: RT3DE is feasible and reproducible for assessment of LV and RV volume, mass, and function, especially in normal fetuses. Gestational growth of these measures, except for EF, is exponential in normal and CHD fetuses. CHD fetuses exhibit diminished LV and RV EFs.


Assuntos
Ecocardiografia Tridimensional/métodos , Feto/fisiologia , Ventrículos do Coração/embriologia , Função Ventricular/fisiologia , Adolescente , Adulto , Estudos de Viabilidade , Feminino , Humanos , Variações Dependentes do Observador , Tamanho do Órgão , Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Reprodutibilidade dos Testes , Fatores de Tempo , Adulto Jovem
7.
Mol Cell Biochem ; 370(1-2): 221-30, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22875667

RESUMO

Porcine satellite cells represent an ideal model system for studying the cellular and molecular basis regulating myogenic stem cell proliferation and differentiation and for exploring the experimental conditions for myoblast transplantation. Here, we investigated the effects of mechano growth factor (MGF), a spliced variant of the IGF-1 gene, on porcine satellite cells. We show that MGF potently stimulated proliferation while inhibited differentiation of porcine satellite cells. MGF-treatment acutely down-regulates the expression of myogenic determination factor (MyoD) and the cyclin-dependent kinase inhibitor p21. MGF-treatment also markedly reduced the overall expression of cyclin B1 and key factors of the myogenic regulatory and myocyte enhancer families, including Myogenein and MEF2A. Taken together, the gene expression data from MGF-treated porcine satellite cells are in favor of a molecular model in which MGF inhibits porcine satellite cell differentiation by down-regulating either the activity or expression of MyoD, which, in turn, suppresses the expression of key genes required for cell cycle progression and differentiation, such as p21, Myogenin, and MEF2. Overall, our findings are in support of the previous suggestion that MGF may be used in vivo and in vitro to promote proliferation of myogenic stem cells to prevent and treat age-related muscle degenerative diseases.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/farmacologia , Desenvolvimento Muscular/genética , Células Satélites de Músculo Esquelético/citologia , Células Satélites de Músculo Esquelético/metabolismo , Fatores de Transcrição/metabolismo , Animais , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Regulação para Baixo/genética , Humanos , Desenvolvimento Muscular/efeitos dos fármacos , Proteína MyoD/genética , Proteína MyoD/metabolismo , Células Satélites de Músculo Esquelético/efeitos dos fármacos , Sus scrofa , Fatores de Transcrição/genética
8.
Echocardiography ; 27(6): 709-15, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20653763

RESUMO

BACKGROUND: Loss of synchronous contraction between or within the right and left ventricle (RV, LV) leads to adverse ventricular function. We used real time three-dimensional echocardiography (RT3DE) for evaluation of severity of interventricular dyssynchrony and function in a porcine heart model. METHODS: Six fresh in vitro porcine hearts were used to create a controlled model of LV and RV dyssynchrony using two sets of pulsatile pumps. Synchronized and dyssynchronized pump settings were used with two different dyssynchronized settings: LV filled first and RV filled first. RESULTS: There was good correlation between actual measurement and RT3DE for interventricular time difference (r = 0.95, P < 0.0001) and stroke volume (SV) for LV and RV (0.89, 0.85; P < 0.0001, respectively). RT3DE data showed a small but significant underestimation for actual volume (P < 0.05). The intra- and interobserver variabilities are 2.9 +/- 1.5% and 3.1 +/- 5.4% for LV and RV SVs, and 1.7 +/- 2.4% and 2.2 +/- 3.2% for time differences by RT3DE. There was significant difference in RV SV between synchrony and dyssynchrony when the RV filled first (P < 0.05), but not in other groups. The same pattern was found in RT3DE derived SVs (synchrony versus dyssynchrony with RV filled first, P < 0.05). CONCLUSIONS: There is no compromise in LV SV during interventricular dyssynchrony; but RV SV was significantly diminished when the RV filled first. RT3DE is a feasible, robust and reproducible method to identify interventricular dyssynchrony and to evaluate ventricular SVs.


Assuntos
Algoritmos , Modelos Animais de Doenças , Ecocardiografia Tridimensional/métodos , Interpretação de Imagem Assistida por Computador/métodos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Direita/diagnóstico por imagem , Animais , Sistemas Computacionais , Humanos , Aumento da Imagem/métodos , Técnicas In Vitro , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Suínos , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Direita/complicações
9.
Am J Cardiol ; 105(10): 1465-9, 2010 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-20451696

RESUMO

Preliminary speckle-tracking echocardiographic studies show that patients with single ventricles (SVs) have significantly decreased twisting and dyssynchrony of twisting. This could be related to abnormal cardiac looping, which leads to hearts that lack helical fiber patterns. The aim of this study was to analyze gradient cine magnetic resonance imaging (MRI) using Velocity Vector Imaging to assess cardiac mechanics. Subjects were 38 patients (aged 8 to 37 years) with SVs of left ventricular (n = 30) and indeterminate (n = 8) type who underwent cardiac MRI. Controls were 14 normal children and adults. Gradient cine MRI sequences close to the apex were subjected to a Velocity Vector Imaging analysis program adapted for MRI. In the control group, mean circumferential strain was -18.02 +/- 7.31%, mean dispersion of peak circumferential strain was 44.23 +/- 37.14 ms, and average rotation was -7.7 +/- 1.38 degrees . The rotation values were negative, or counterclockwise. In patients with SVs, mean circumferential strain was -8.87 +/- 7.30%, mean dispersion of peak circumferential strain was 181.55 +/- 76.07 ms, and average rotation was -2.6 +/- 1.24 degrees (p <0.001). Mean dispersion of the peak of rotation in the control group was 39.6 +/- 22.8 ms, compared to 166.5 +/- 72.4 ms in patients with SVs. In conclusion, this study showed a dramatic decrease in apical rotation and circumferential strain in the SV group compared to the control group. Strain and rotation mechanics at the apex in patients with SVs showed marked dyssynchrony.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Cardiopatias Congênitas/diagnóstico , Ventrículos do Coração/anormalidades , Imagem Cinética por Ressonância Magnética/métodos , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Feminino , Derivação Cardíaca Direita/métodos , Cardiopatias Congênitas/mortalidade , Cardiopatias Congênitas/cirurgia , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Valores de Referência , Medição de Risco , Sensibilidade e Especificidade , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
10.
J Huazhong Univ Sci Technolog Med Sci ; 29(5): 669-72, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19821107

RESUMO

The left ventricular radial strain in the inner and outer layers was evaluated by using two-dimensional speckle tracking imaging (2DS). Twenty-five piglets were studied. The short axis views were acquired. Peak systolic radial strain was measured from 6 circumferential points related to 6 standard segments in the inner and outer layers respectively using 2DS methods. The peak positive first derivative (dp/dt) of left ventricular pressure was compared to the radial strain from 2DS. The inner band showed higher peak radial strain values as compared to the outer band at all of the segments (P<0.0001), but the differences had significance just in anteroseptal, posterior, inferior and septal segments (P<0.05). Good correlation could be found between radial strain of inner and outer layers and peak dp/dt (P<0.001). These preliminary results showed that the degree of local deformation or wall thickening of the ventricular wall in its inner layer was more obvious than its outer layer. It is suggested that the 2DS technique is useful and sensitive for better understanding the regional and global myocardial motion and its relationship to the complex architecture of myocardium.


Assuntos
Ecocardiografia/métodos , Cardiopatias/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Anormalidade Torcional/diagnóstico por imagem , Animais , Técnicas de Imagem por Elasticidade/métodos , Cardiopatias/fisiopatologia , Ventrículos do Coração/fisiopatologia , Suínos , Porco Miniatura , Torção Mecânica
12.
J Colloid Interface Sci ; 318(2): 389-96, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18005979

RESUMO

Mixed micelle formation and synergistic interactions of binary surfactant combinations of sodium nonylphenol polyoxyethylene ether sulfate (NPES) with typical surfactants such as sodium dodecyl sulfate (SDS), Triton X-100 (TX100), cetyl trimethyl ammonium bromide (CTAB), and sodium bis(2-ethylhexyl) sulfosuccinate (AOT) at 25 degrees C in the presence of NaCl have been investigated. The critical micelle concentration of the binary mixtures has been quantitatively estimated by steady-state fluorescence measurements. The micellar characteristics such as composition, activity coefficients, and mutual interaction parameters have been estimated following different theoretical treatments. Investigation on the micellization and synergistic interaction of NPES with four kinds of surfactants showed that the behavior of the binary mixture deviated from the ideal state. The analysis revealed that the interaction parameter values (beta) varied with variation of solvent composition. Besides the strong electrostatic attraction between the oppositely charged surfactant NPES-CTAB mixture, the interaction between NPES and SDS also showed far more deviation from ideal behavior than that of TX100 and AOT. The reason for the synergism is also discussed and the results show that an ionic and a nonionic surfactant character existed concurrently in NPES due to the combination of a sulfate group and polyoxyethylene as a hydrophilic moiety. Zeta potential and diffusion coefficient measurements of micelles confirmed the synergistic interaction between the binary surfactants.


Assuntos
Éteres/química , Polietilenoglicóis/química , Tensoativos/química , Cetrimônio , Compostos de Cetrimônio/química , Difusão , Ácido Dioctil Sulfossuccínico/química , Micelas , Estrutura Molecular , Octoxinol/química , Cloreto de Sódio/química , Dodecilsulfato de Sódio/química , Soluções/química , Propriedades de Superfície
13.
J Am Coll Cardiol ; 46(12): 2284-9, 2005 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-16360059

RESUMO

OBJECTIVES: We sought to evaluate the effects of biventricular (BDOO) pacing compared with conventional (CDOO) atrioventricular (AV) sequential and atrial (AOO) pacing in children and infants in the early postoperative period after open heart surgery for congenital heart disease (CHD). BACKGROUND: Biventricular pacing using right ventricular (RV) and left ventricular (LV) leads can improve hemodynamics in patients with CHD, but it is unclear whether this occurs in early postoperative children with CHD. METHODS: Nineteen children (age, 5 days to 5.4 years; median, 5.5 months) with a definitive biventricular repair for CHD underwent AOO, CDOO, and BDOO pacing with temporary epicardial leads for 10 min each. The AV delay was 80% of the PR interval for the CDOO and BDOO modes. Lead placement was two right atrial, two RV, and one LV. Blood samples for cardiac index (arterial and venous) and tissue Doppler (TDI) traces were obtained in each pacing mode with a Vivid 7 BT04 digital ultrasound system (GE/VingMed, Horten, Norway) from an apical four-chamber view and analyzed with EchoPac software. RESULTS: The QRS duration was significantly shorter for BDOO compared with CDOO, and the cardiac index was higher with BDOO compared with CDOO. Systemic blood pressure was not different between the three modes of pacing (AOO, CDOO, BDOO). The TDI-derived strain rate showed minimal dyssynchrony in AOO as seen by isovolumic tensing (IVT) and peak systolic contraction (PSC) timing differences between RV and LV. The CDOO worsened dyssynchrony with prolonged DeltaIVT and PSC. The BDOO showed improved synchrony as seen by DeltaIVT and PSC. CONCLUSIONS: The TDI-derived strain rate showed worsened ventricular dyssynchrony with CDOO and improvement with BDOO. Cardiac index and QRS duration were improved by BDOO compared with CDOO. This suggests that short-term pacing with BDOO may benefit children with CHD needing pacing in the postoperative period.


Assuntos
Estimulação Cardíaca Artificial/métodos , Ecocardiografia Doppler , Cardiopatias Congênitas/fisiopatologia , Cardiopatias Congênitas/terapia , Hemodinâmica , Pressão Sanguínea , Débito Cardíaco , Estimulação Cardíaca Artificial/efeitos adversos , Estimulação Cardíaca Artificial/normas , Pré-Escolar , Eletrocardiografia , Feminino , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/diagnóstico , Ventrículos do Coração , Humanos , Lactente , Recém-Nascido , Masculino , Resultado do Tratamento , Disfunção Ventricular/etiologia , Disfunção Ventricular/fisiopatologia
14.
J Am Soc Echocardiogr ; 18(10): 1030-6, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16198879

RESUMO

BACKGROUND: Invasive monitors and noninvasive 2-dimensional echocardiography are the standard clinical methods for stroke volume (SV) and cardiac output computation. We studied the use of real-time color Doppler 3-dimensional (3D) echocardiography (3DE) for the assessment of SV in human beings. METHODS: In all, 55 pediatric and adult patients with good transthoracic windows and a normal aortic valve were studied. Real-time 3DE color Doppler volumes incorporating the left ventricular outflow tract and aortic valve were taken. SV was calculated from the color Doppler data in the 3DE DICOM dataset. This was compared with 2-dimensional echocardiography SV calculation from the pulsed wave velocity through the aortic valve along with the left ventricular outflow tract diameter. RESULTS: Five patients were excluded because of mismatching of the 3D color Doppler segments in the 3D volume. The 3D Doppler volumes from the remaining 50 patients were analyzed. There was good correlation between the patients' averaged 3DE SV calculations and the 2-dimensional echocardiography pulsed wave SV estimation (y = 0.84x + 7.8, r2 = 0.90). CONCLUSION: Real-time 3D Doppler echocardiography can be used to accurately calculate SV and cardiac output, compared with conventional pulsed Doppler measurement, in pediatric and adult patients from transthoracic imaging.


Assuntos
Débito Cardíaco , Ecocardiografia Doppler/métodos , Ecocardiografia Tridimensional/métodos , Interpretação de Imagem Assistida por Computador/métodos , Volume Sistólico , Disfunção Ventricular Esquerda/diagnóstico por imagem , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Sistemas Computacionais , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Circ Res ; 97(6): 583-6, 2005 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-16100048

RESUMO

Protection by ischemic preconditioning is lost in cardiomyocytes and hearts of heterozygous connexin 43 deficient (Cx43+/-) mice. Because connexin 43 (Cx43) is localized in cardiomyocyte mitochondria and mitochondrial Cx43 content is increased with ischemic preconditioning, we now tried to identify a functional defect at the level of the mitochondria in Cx43+/- mice by use of diazoxide and menadione. Diazoxide stimulates the mitochondrial formation of reactive oxygen species (ROS) and menadione generates superoxide at multiple intracellular sites; both substances elicit cardioprotection through increased ROS formation. ROS formation in response to the potassium ionophore valinomycin was also measured for comparison. Menadione (2 micromol/L) and valinomycin (10 nmol/L) induced similar ROS formation in wild-type (WT) and Cx43+/- cardiomyocytes. In contrast, diazoxide (200 micromol/L) increased ROS formation by 43+/-10% versus vehicle in WT, but only by 18+/-4% in Cx43+/- cardiomyoctes (P<0.05). Two hour-simulated ischemia and oxygenated, hypo-osmolar reperfusion reduced viability as compared with normoxia (WT: 7+/-1% versus 39+/-2%, (Cx43+/-): 8+/-1% versus 40+/-3%, P<0.01). Although menadione protected WT and Cx43+/- cardiomyocytes, diazoxide increased viability (17+/-2%, P<0.01) in WT, but not in Cx43+/- (9+/-1%). Menadione (37 microg/kg i.v.) before 30 minutes coronary occlusion and 2 hour reperfusion reduced infarct size in WT and Cx43+/- mice (24+/-4% versus 24+/-5%). In contrast, diazoxide (5 mg/kg i.v.) reduced infarct size in WT (35+/-4% versus 55+/-3% of area at risk, P<0.01), but not in Cx43+/- mice (56+/-2% versus 54+/-3%). Cardiomyocytes of Cx43+/- mice have a specific functional deficit in ROS formation in response to diazoxide and accordingly less protection.


Assuntos
Conexina 43/fisiologia , Diazóxido/farmacologia , Precondicionamento Isquêmico Miocárdico , Miócitos Cardíacos/metabolismo , Espécies Reativas de Oxigênio , Animais , Camundongos , Mitocôndrias Cardíacas/metabolismo , Substâncias Protetoras/farmacologia , Valinomicina/farmacologia , Vitamina K 3/farmacologia
17.
J Ultrasound Med ; 24(8): 1109-15, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16040826

RESUMO

OBJECTIVES: We and others have reported on the use of digital color Doppler sonography from real-time 3-dimensional (3D) echocardiography and its use in accurately calculating cardiac flow volumes, namely stroke volume (SV) and, hence, cardiac output. However, in some patients, image depth is higher than average, and this may affect the accuracy of volume calculation. We sought to investigate the impact of image depth and the accompanying change in signal strength, spatial resolution, and pulse repetition frequency on the accuracy of SV calculation from 3D color Doppler data in an in vitro model. METHODS: A tube model of the left ventricular outflow tract was constructed from plastic tubing and connected to a pulsatile pump. The volume flowing through the tube was imaged using a 3D echocardiography system. Stroke volumes from the pump were computed from the DICOM data using commercially available software and compared with a reference standard of timed volumes with the use of a graduated measuring cylinder over a range of depth settings and SVs. RESULTS: There was good correlation between the 3D-derived SVs and the reference cylinder measures over all depths from 4 to 16 cm at 1-cm increments with a tube diameter of 17 mm, a pump rate of 60 beats/min, and SVs ranging from 20 to 70 mL. The average r(2) value for the 13 different depths was 0.976. However, the accuracy of the 3D method of volume calculation appeared to fall at depths greater than 13 cm, especially at higher SVs. CONCLUSIONS: Stroke volume calculation from real-time 3D color Doppler data in this in vitro study shows that at depths greater than approximately 13 cm, accuracy decreases, especially at higher SVs. This may be due to decreased resolution and the reduced frame rate at these depths. At shallower depths, volume calculation form the 3D Doppler data appears very accurate.


Assuntos
Ecocardiografia Doppler em Cores/métodos , Ecocardiografia Tridimensional/métodos , Volume Sistólico , Análise de Variância , Desenho de Equipamento , Humanos , Modelos Lineares , Imagens de Fantasmas , Fluxo Pulsátil
18.
Eur J Echocardiogr ; 6(6): 396-404, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15927537

RESUMO

AIMS: Laminar flow stroke volume (SV) quantification in the ascending aorta or pulmonary artery can provide a measure for determining cardiac output (CO). Comparing flows across different valves can also compute shunt volumes and regurgitant fractions. Quantification methods for 3D color Doppler laminar flow volumes have been developed using reconstructive 3D, but these are cumbersome and time-consuming both in acquisition and measurement. Our study evaluated newly developed color Doppler mapping with real-time live 3D echo to test velocity, spatial and temporal resolution for computing SV. METHODS AND RESULTS: Five rubber tubes (diameters=3.0, 2.25, 2.0, 1.9, 1.7 cm), a freshly dissected porcine aorta (Ao) and a pulmonary artery (PA) (both 2-3 cm diameter) were connected to a pulsatile pump in a water bath. Different SV, from 10 to 80 ml/beat, were studied at pump rates of 40-60 bpm in this phantom model with flow quantified by timed collection. The Nyquist limit was set between 43 and 100 cm/s and frame rate ranged from 14 to 23/s. ECG triggered 3D color Doppler volumes were acquired with a 2-4 MHz probe. The digital scan line data from the 3D volumes, with retained velocity assignments, was exported and analyzed offline by MatLab custom software. Close correlations were found between 3D calculated SV and reference data for all tubes (r=0.98, y=1.14x-1.69, SEE=2.82 ml/beat, p<0.0001). Both Ao and PA flows were also highly correlated with the reference measurements (PA: r=0.98, SEE=3.17 ml/beat; Ao: r=0.99, SEE=3.20 ml/beat). CONCLUSIONS: Real-time 3D color Doppler method could provide an efficient, accurate and reliable method for clinical evaluation and quantification of flow volumes in patients.


Assuntos
Ecocardiografia Doppler em Cores/métodos , Ecocardiografia Tridimensional/métodos , Volume Sistólico/fisiologia , Animais , Aorta/diagnóstico por imagem , Aorta/fisiologia , Débito Cardíaco/fisiologia , Ecocardiografia Doppler em Cores/instrumentação , Ecocardiografia Doppler em Cores/normas , Ecocardiografia Tridimensional/instrumentação , Ecocardiografia Tridimensional/normas , Técnicas In Vitro , Modelos Anatômicos , Modelos Cardiovasculares , Variações Dependentes do Observador , Artéria Pulmonar/diagnóstico por imagem , Artéria Pulmonar/fisiologia , Suínos
19.
J Am Coll Cardiol ; 45(3): 433-8, 2005 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-15680724

RESUMO

OBJECTIVES: The purpose of this study was to investigate whether cardiac output (CO) could be accurately computed from live three-dimensional (3-D) Doppler echocardiographic data in an acute open-chested animal preparation. BACKGROUND: The accurate measurement of CO is important in both patient management and research. Current methods use invasive pulmonary artery catheters or two-dimensional (2-D) echocardiography or esophageal aortic Doppler measures, with the inherent risks and inaccuracies of these techniques. METHODS: Seventeen juvenile, open-chested pigs were studied before undergoing a separate cardiopulmonary bypass procedure. Live 3-D Doppler echocardiography images of the left ventricular outflow tract and aortic valve were obtained by epicardial scanning, using a Philips Medical Systems (Andover, Massachusetts) Sonos 7500 Live 3-D Echo system with a 2.5-MHz probe. Simultaneous CO measurements were obtained from an ultrasonic flow probe placed around the aortic root. Subsequent offline processing using custom software computed the CO from the digital 3-D Doppler DICOM data, and this was compared to the gold standard of the aortic flow probe measurements. RESULTS: One hundred forty-three individual CO measurements were taken from 16 pigs, one being excluded because of severe aortic regurgitation. There was good correlation between the 3-D Doppler and flow probe methods of CO measurement (y = 1.1x - 9.82, R(2) = 0.93). CONCLUSIONS: In this acute animal preparation, live 3-D Doppler echocardiographic data allowed for accurate assessment of CO as compared to the ultrasonic flow probe measurement.


Assuntos
Débito Cardíaco , Ecocardiografia Doppler em Cores , Ecocardiografia Tridimensional , Animais , Velocidade do Fluxo Sanguíneo , Ponte Cardiopulmonar , Estudos de Viabilidade , Humanos , Processamento de Imagem Assistida por Computador , Modelos Animais , Reprodutibilidade dos Testes , Suínos
20.
J Am Soc Echocardiogr ; 18(1): 1-7, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15637481

RESUMO

We developed and assessed a real-time 3-dimensional (3D) digital Doppler method for measurement of flow volumes through the mitral valve in children. A total of 13 children (aged 10.46 +/- 2.5 years; 8 boys/5 girls) were enrolled. An ultrasound system (Sonos 7500, Philips, Andover, Mass) was used to acquire raw 3D velocity data for flow measurement based on Gaussian control surface theorem [flow (mL/s) = mean velocity x flow area]. Stroke volume (SV) measured by real-time 3D digital Doppler with the control surface at the mitral valve annulus or orifice was compared with the SV by phase velocity cine magnetic resonance imaging (MRI) at the ascending aorta and by left ventricular volumetric MRI measurement. The best correlation and agreement were seen at the mitral valve orifice by real-time 3D digital Doppler compared with SV by phase velocity cine MRI at the ascending aorta (r = 0.92, mean difference = -5.2 +/- 12.0 mL) and SV by left ventricular volumetric MRI measurement (r = 0.94, mean difference = -0.2 +/- 10.3 mL).


Assuntos
Ecocardiografia Doppler/métodos , Imageamento Tridimensional/métodos , Valva Mitral/fisiologia , Adolescente , Criança , Estudos de Viabilidade , Feminino , Humanos , Masculino , Estudos Prospectivos , Fluxo Sanguíneo Regional , Volume Sistólico
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