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1.
Nat Commun ; 15(1): 2294, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38480724

RESUMO

Ion trapping has been found to be responsible for the performance degradation in electrochromic oxide thin films, and a detrapping procedure was proved to be effective to rejuvenate the degraded films. Despite of the studies on ion trapping and detrapping, its dynamics remain largely unknown. Moreover, coloration mechanisms of electrochromic oxides are also far from clear, limiting the development of superior devices. Here, we visualize ion trapping and detrapping dynamics in a model electrochromic material, amorphous WO3. Specifically, formation of orthorhombic Li2WO4 during long-term cycling accounts for the origin of shallow traps. Deep traps are multiple-step-determined, composed of mixed W4+-Li2WO4, amorphous Li2WO4 and W4+-Li2O. The non-decomposable W4+-Li2WO4 couple is the origin of the irreversible traps. Furthermore, we demonstrate that, besides the typical small polaron hopping between W5+ ↔ W6+ sites, bipolaron hopping between W4+ ↔ W6+ sites gives rise to optical absorption in the short-wavelength region. Overall, we provide a general picture of electrochromism based on polaron hopping. Ion trapping and detrapping were demonstrated to also prevail in other cathodic electrochromic oxides. This work not only provides the ion trapping and detrapping dynamics of WO3, but also open avenues to study other cathodic electrochromic oxides and develop superior electrochromic devices with great durability.

2.
J Ultrasound Med ; 42(6): 1235-1248, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36445006

RESUMO

OBJECTIVES: Ultrasound (US) is important for diagnosing infant developmental dysplasia of the hip (DDH). However, the accuracy of the diagnosis depends heavily on expertise. We aimed to develop a novel automatic system (DDHnet) for accurate, fast, and robust diagnosis of DDH. METHODS: An automatic system, DDHnet, was proposed to diagnose DDH by analyzing static ultrasound images. A five-fold cross-validation experiment was conducted using a dataset containing 881 patients to verify the performance of DDHnet. In addition, a blind test was conducted on 209 patients (158 normal and 51 abnormal cases). The feasibility and performance of DDHnet were investigated by embedding it into ultrasound machines at low computational cost. RESULTS: DDHnet obtained reliable measurements and accurate diagnosis predictions. It reported an intra-class correlation coefficient (ICC) on α angle of 0.96 (95% CI: 0.93-0.97), ß angle of 0.97 (95% CI: 0.95-0.98), FHC of 0.98 (95% CI: 0.96-0.99) and PFD of 0.94 (95% CI: 0.90-0.96) in abnormal cases. DDHnet achieved a sensitivity of 90.56%, specificity of 100%, accuracy of 98.64%, positive predictive value (PPV) of 100%, and negative predictive value (NPV) of 98.44% for the diagnosis of DDH. For the measurement task on the US device, DDHnet took only 1.1 seconds to operate and complete, whereas the experienced senior expert required an average 41.4 seconds. CONCLUSIONS: The proposed DDHnet demonstrate state-of-the-art performance for all four indicators of DDH diagnosis. Fast and highly accurate DDH diagnosis is achievable through DDHnet, and is accessible under constrained computational resources.


Assuntos
Displasia do Desenvolvimento do Quadril , Luxação Congênita de Quadril , Lactente , Humanos , Inteligência Artificial , Luxação Congênita de Quadril/diagnóstico por imagem , Ultrassonografia/métodos , Valor Preditivo dos Testes
3.
Rev Sci Instrum ; 93(12): 125112, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36586916

RESUMO

Transient grating spectroscopy (TGS) based on diffraction gratings is a powerful optical method for studying the transport of energy carriers such as phonons and electrons. The diffraction grating in a TGS system is a key component to form a large-area interference pattern, i.e., transient grating, and to study the mean free path distribution of energy carriers. In this work, a design method for polarization-insensitive diffraction gratings with periods in the range 2-50 µm for TGS by a combination of rigorous coupled wave analysis and genetic algorithm was discussed. The method was tested for pump/probe wavelength of 515/532 or 1030/808 nm. Each ±1st diffraction order carries 35%-40% of the incident energy and the diffraction efficiencies of the other orders are lower than 10%. The optimized diffraction gratings were fabricated by a combination of photolithography and inductively coupled plasma etching, with the processing parameters introduced in detail, and their optical characteristics were evaluated. Finally, as a demonstration, the diffraction gratings for 1030/808 nm were applied to TGS to study the thermal transport properties of Ge. This work provides a useful guide for future applications and the development of TGS.

4.
Mol Genet Genomics ; 296(6): 1287-1298, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34553246

RESUMO

Verticilllium wilt of cotton is a devastating soil-borne disease, which is caused by Verticillium dahliae Kleb. Bacillus velezensis strain AL7 was isolated from cotton soil. This strain efficiently inhibited the growth of V. dahliae. But the mechanism of the biocontrol strain AL7 remains poorly understood. To understand the possible genetic determinants for biocontrol traits of this strain, we conducted phenotypic, phylogenetic and comparative genomics analysis. Phenotypic analysis showed that strain AL7 exhibited broad-spectrum antifungal activities. We determined that the whole genome sequence of B. velezensis AL7 is a single circular chromosome that is 3.89 Mb in size. The distribution of putative gene clusters that could benefit to biocontrol activities was found in the genome. Phylogenetic analysis of Bacillus strains by using single core-genome clearly placed strain AL7 into the B. velezensis. Meantime, we performed comparative analyses on four Bacillus strains and observed subtle differences in their genome sequences. In addition, comparative genomics analysis showed that the core genomes of B. velezensis are more abundant in genes relevant to secondary metabolism compared with B. subtilis strains. Single mutant in the biosynthetic genes of fengycin demonstrated the function of fengycin in the antagonistic activity of B. velezensis AL7. Here, we report a new biocontrol bacterium B. velezensis AL7 and fengycin contribute to the biocontrol efficacy of the strain. The results showed in the research further sustain the potential of B. velezensis AL7 for application in agriculture production and may be a worthy biocontrol strain for further studies.


Assuntos
Bacillus/genética , Agentes de Controle Biológico/metabolismo , Gossypium/microbiologia , Lipopeptídeos/metabolismo , Doenças das Plantas/prevenção & controle , Verticillium/crescimento & desenvolvimento , Antifúngicos/metabolismo , Genoma Bacteriano/genética , Lipopeptídeos/genética , Doenças das Plantas/microbiologia , Metabolismo Secundário/genética , Microbiologia do Solo , Sequenciamento Completo do Genoma
5.
Pest Manag Sci ; 77(4): 1829-1838, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33270979

RESUMO

BACKGROUND: Cotton has been increasingly harmed by the mirid bug (Lygus pratensis Linnaeus) in Xinjiang Uyghur Autonomous Region, China. Using trap plants within or around the border of the cotton may be a beneficial management strategy for this pest of cotton. RESULTS: The potential of safflower (Carthamus tinctorius Linn) as a trap plant for managing L. pratensis was evaluated in laboratory and field experiments. Y-tube olfactometer assays demonstrated that L. pratensis was highly attracted to volatiles derived from safflower. Field experiments showed that safflower plots hosted more L. pratensis (adults and nymphs) than cotton plots. Early-sown safflower had more L. pratensis than mid-sown or late-sown safflower, and was more conducive to the settlement and reproduction of L. pratensis. The density of L. pratensis on safflower trap crops in three sowing patterns was significantly higher than on adjacent cotton. The pattern of intercropping safflower trap crops was more effective at reducing densities of L. pratensis on cotton than placing safflower as 'spot' trap crops or peripheral trap crops. However, this result also may be related to the overall area of the safflower trap crops. With regular chemical control of L. pratensis on safflower trap crops, the number of cotton bolls was increased by 10.04%, whereas the rate of boll damage was reduced by 33.44%, compared to cotton without safflower trap crops and insecticide sprays. CONCLUSION: Safflower shows promise as an effective trap crop for L. pratensis, and may contribute to controlling L. pratensis in cotton. © 2020 Society of Chemical Industry.


Assuntos
Carthamus tinctorius , Heterópteros , Animais , China , Produtos Agrícolas , Gossypium , Ninfa
6.
PLoS One ; 15(8): e0237318, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32804952

RESUMO

The mirid bug Lygus pratensis is an important pest of cotton, and is primarily managed through insecticide application. In this study, conducted in Xinjiang (China), we assessed the relative attractiveness of sunflower (Helianthus annuus) to L. pratensis adults in local cotton plots from 2015-2016 and quantified the associated contribution of inter-planted sunflower strips to suppress field-level L. pratensis populations from 2016-2017. Field-plot trials showed that among six combinations of two sunflower varieties (XKZ6 and SH363) and three planting dates (early-, middle- and late-planted), adult abundance of L. pratensis was highest on early-planted XKZ6 and attained 3.7-5.8 times higher levels than in neighboring cotton plots. In commercial cotton fields, the combined deployment of sunflower strips at field edges and the periodic application of insecticides directed to those strips was found to (1) reduce the mean abundance of L. pratensis population on cotton by 41.9-44.0%, (2) lower the rate of cotton leaf damage by 27.3-30.6% and boll damage by 44.8-46.0%, and (3) increase the number of mature bolls by 7.5%-8.0%. Our work emphasizes how sunflower can be an effective trap crop for L. pratensis and that the establishment of sunflower strips could contribute to its effective and environmentally-sound management in cotton crops.


Assuntos
Proteção de Cultivos/métodos , Produtos Agrícolas/parasitologia , Gossypium/parasitologia , Helianthus/parasitologia , Heterópteros/fisiologia , Animais , China , Comportamento Alimentar , Folhas de Planta/parasitologia
7.
Microbiol Resour Announc ; 9(8)2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32079637

RESUMO

Bacillus velezensis AL7, isolated from cotton soil, had strong antagonistic activity to Verticillium dahlia Kleb. The AL7 genome consisted of one chromosome with 3,894,709 bp (46.64% G+C content). Genome annotation predicted 3,706 protein-coding genes, 86 tRNAs, and 27 rRNAs. We sequenced and annotated the complete AL7 genome to help us better understand use of this strain.

8.
J Card Surg ; 28(5): 580-6, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24015993

RESUMO

AIMS: Common atrium (CA) is a rare congenital heart defect. We reviewed our experience of surgical treatment of CA and summarize the clinical features of CA and the key techniques for surgical correction. METHODS: Between August 1984 and August 2010, 37 consecutive cases of CA underwent corrective surgery. There were no clinical findings of Down, asplenia-polysplenia or Ellis-van Creveld syndromes in all cases. Mitral valvuloplasty was performed in 34 cases, and tricuspid valvuloplasty in 20 cases. Complete closure of a mitral cleft was required in 32 cases. All new atrial septa were reconstructed using patches. Follow-up period ranged from 1 to 20 years. RESULTS: There were no hospital deaths or conduction system block. After surgery, mild mitral insufficiency was observed in only one case. Two cases had moderate-severe mitral insufficiency at postoperative years 1 and 3, respectively, that required mitral valve replacements. One patient died of low cardiac output syndrome after reoperation. CONCLUSIONS: Long-term survival after surgical correction of CA is good. Routine closure of a cleft in the mitral valve is very important for successful surgery.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Cardiopatias Congênitas/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Adolescente , Adulto , Procedimentos Cirúrgicos Cardíacos/mortalidade , Anuloplastia da Valva Cardíaca/mortalidade , Criança , Pré-Escolar , Ecocardiografia , Feminino , Átrios do Coração/anormalidades , Átrios do Coração/cirurgia , Cardiopatias Congênitas/diagnóstico por imagem , Septos Cardíacos/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/cirurgia , Procedimentos de Cirurgia Plástica/mortalidade , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Valva Tricúspide/cirurgia , Adulto Jovem
9.
Ann Thorac Surg ; 93(2): 620-5, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22269727

RESUMO

BACKGROUND: Right-side heart function is essentially externalized during extracardiac total cavopulmonary connection. The Fontan procedure has a certain impact on pulmonary hemoperfusion and may explain various postsurgical complications. In this study, alterations of pulmonary perfusion in patients undergoing the Fontan procedure were analyzed at the 5-year postoperative mark by radionuclide imaging and angiocardiography, and results of both methods were compared. METHODS: For 43 post-Fontan patients, perfusion ratios of each lung segment were calculated based on radionuclide imaging data. The pulmonary vascular resistance and pulmonary artery index of each patient were also calculated from right angiocardiographic measurements. RESULTS: The radionuclide count and advantage perfusion ratio of right lung at follow-up did not differ significantly from early postoperative values (t=0.38, p>0.05; t=1.12, p>0.05), and superior/inferior vena cava perfusion ratios were stable (t=0.88, p>0.05; t=0.74, p>0.05). The superior/inferior segment perfusion ratio of the whole lung declined significantly (t=2.54, p<0.05), while that of the dorsal lung segment rose significantly (t=2.16, p<0.05). Compared with early postoperative status, the pulmonary arterial index of patients at follow-up were significantly increased (t=2.41, p<0.05), while small pulmonary vascular resistances declined significantly (t=2.08, p<0.05; t=2.69, p<0.05), and arterial oxygen saturation levels were unaltered (t=1.12, p>0.05). The early angiographic and radionuclide perfusion studies of 5 patients did not match. CONCLUSIONS: After the Fontan procedure, hypostatic redistribution of pulmonary blood flow is characteristic. The weak pulse of blood, in the absence of ventricular ejection, can promote pulmonary vascular changes, but at later (intermediate) follow-up, the decline in vascular resistance that results carries no benefit in terms of blood perfusion or oxygenation. Microcirculatory arteriovenous shunting is the likely cause. In this study of functional pulmonary hemoperfusion, radionuclide imaging was deemed superior to angiocardiography.


Assuntos
Angiocardiografia , Técnica de Fontan , Pulmão/diagnóstico por imagem , Imagem de Perfusão , Artéria Pulmonar/fisiopatologia , Circulação Pulmonar , Adolescente , Adulto , Cateterismo Cardíaco , Criança , Pré-Escolar , Feminino , Cardiopatias Congênitas/cirurgia , Humanos , Pulmão/irrigação sanguínea , Masculino , Microcirculação , Oxigênio/sangue , Pressão Parcial , Período Pós-Operatório , Compostos Radiofarmacêuticos , Agregado de Albumina Marcado com Tecnécio Tc 99m , Resultado do Tratamento , Resistência Vascular , Veia Cava Inferior/fisiopatologia , Veia Cava Superior/fisiopatologia , Adulto Jovem
10.
Nucl Med Commun ; 33(2): 148-54, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22107998

RESUMO

OBJECTIVE: To explore the changes of pulmonary perfusion over 5 years in patients who underwent extracardiac total cavopulmonary connection. METHODS: Forty-three patients who had undergone extracardiac total cavopulmonary connection were examined with pulmonary perfusion 1 month and 5 years following the operation. 99mTc-MAA was used for perfusion imaging; pulmonary perfusion value and blood distribution were measured and calculated. Vena cava pressure and arterial oxygenation were measured using the right cardiac catheter, and the pulmonary arteriole resistance was calculated. The status of the conduit connection was assessed by computed tomography three-dimensional reconstruction. RESULTS: Radionuclide counts of the follow-up group were similar to those of the early postoperative group, and the ratios of right to left pulmonary perfusion and inferior vena cava perfusion were not changed. However, the ratio of the whole pulmonary superior to inferior segment was remarkably reduced (t=2.54, P<0.05), with a significantly higher perfusion rate in the posterior segment of the lower lobe (t=2.16, P<0.05). The pulmonary arteriole resistance of the follow-up group was reduced significantly (t=2.08, P<0.05). The vena cava pressure was also reduced (t=2.69, P<0.05), but oxygenation was not significantly changed. Five patients showed a mismatch between pulmonary angiography and radionuclide scintigraphy soon after the operation. The pulmonary angiography showed that the anastomosis was patent, and both lungs were demonstrated. However, the radionuclide scintigraphy only demonstrated the unilateral lung soon after the operation, and both lungs were demonstrated during follow-up. CONCLUSION: Radionuclide scintigraphy is superior to the pulmonary angiography in the study of functional pulmonary perfusion. Fontan circulation may lead to gravity-dependent blood redistribution, and its weak pulsation can promote pulmonary vascular development. However, the reduced pulmonary arterial resistance at mid-term follow-up may not lead to an increased amount of pulmonary perfusion or oxygen supply, which is probably because of the massive opening of the arteriovenous shunt and increased futile circulation.


Assuntos
Circulação Pulmonar/fisiologia , Veia Cava Inferior/diagnóstico por imagem , Veia Cava Superior/diagnóstico por imagem , Adolescente , Adulto , Criança , Pré-Escolar , Angiografia Coronária/métodos , Feminino , Seguimentos , Técnica de Fontan , Humanos , Imageamento Tridimensional , Masculino , Compostos de Organotecnécio , Oxigênio/sangue , Artéria Pulmonar/cirurgia , Cintilografia , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Veia Cava Inferior/cirurgia , Veia Cava Superior/cirurgia , Adulto Jovem
11.
Asian Cardiovasc Thorac Ann ; 17(1): 39-44; discussion 45, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19515878

RESUMO

Cardiopulmonary adaptation during exercise was compared in patients with an extracardiac total cavopulmonary connection and controls with biventricular repair of Fallot's tetralogy. Heart rate, blood pressure, respiratory frequency, and transcutaneous oxygen saturation increased with treadmill exercise intensity below grade 3 in patients who had undergone extracardiac total cavopulmonary connection. When exercise intensity exceeded grade 4, blood pressure and oxygen saturation decreased continuously, respiratory rate kept increasing, and heart rate showed no significant change. In cases of fenestrated cavopulmonary connection, heart rate peaked at grade 5 exercise intensity, and blood pressure at grade 4; but both peaked at grade 3 in non-fenestrated patients. During all exercise testing, fenestrated patients had a higher respiratory rate but lower oxygen saturation than those without fenestration. Exercise tolerance was below normal after a cavopulmonary connection, but patients still adapted to exercise below grade 3 with appropriate increases in heart rate and respiratory rate. Due to insufficient right heart systems, patients with a cavopulmonary connection showed obvious exercise limitation at exercise intensity grade 3 or more. Total exclusion of the right heart system may also have adverse effects on the sinoatrial node, leading to impaired heart rate regulation.


Assuntos
Adaptação Fisiológica , Tolerância ao Exercício , Técnica de Fontan/métodos , Derivação Cardíaca Direita/métodos , Cardiopatias Congênitas/cirurgia , Adolescente , Adulto , Pressão Sanguínea , Criança , Pré-Escolar , Teste de Esforço , Feminino , Cardiopatias Congênitas/fisiopatologia , Frequência Cardíaca , Humanos , Masculino , Oxigênio/sangue , Mecânica Respiratória , Adulto Jovem
12.
Zhonghua Wai Ke Za Zhi ; 45(12): 808-11, 2007 Jun 15.
Artigo em Chinês | MEDLINE | ID: mdl-17845776

RESUMO

OBJECTIVE: To study cardiopulmonary physiology during exercise in patients after extracardiac total cavopulmonary connection (ECTCPC). METHODS: Twenty-six patients were studied after ECTCPC by exercise testing with bicycle treadmill protocol. Heart rate (HR), blood pressure (BP), respiratory frequency (RF) and pulse oxygen saturation (SpO(2)) were measured continuously; twenty-six patients suffered from Fallot 4 underwent biventricular repair were also studied as control group. RESULTS: In ECTCPC group, HR, BP, SpO(2) and RF all increased with exercise below 3 grade; when exceed 4 grade, BP, SpO(2) decreased and RF kept increasing. Compared with control group, HR, RF were higher (t = 2.13, P < 0.05; t = 2.31, P < 0.05), SpO(2) was lower (t = 2.46, P < 0.05) under the quiescent condition; When exceed 3 grade, HR, BP, SpO(2) decreased more significantly, but RF increased continuously. In fenestration group after ECTCPC, HR reached the top at 5 grades, but in group without fenestration it reached the top at 3 grades; In the whole process of exercising, RF kept higher and SpO(2) kept lower in fenestration group. CONCLUSIONS: The ECTCPC patients showed obviously exercise limitation. Totally bypass of sinoatrial node in this operation may have some adverse effects on the integer regulation of HR.


Assuntos
Técnica de Fontan/métodos , Cardiopatias Congênitas/fisiopatologia , Resistência Física/fisiologia , Adolescente , Adulto , Criança , Pré-Escolar , Teste de Esforço , Feminino , Seguimentos , Cardiopatias Congênitas/cirurgia , Humanos , Masculino , Período Pós-Operatório
13.
Zhonghua Wai Ke Za Zhi ; 44(18): 1229-31, 2006 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-17147877

RESUMO

OBJECTIVE: To summarize the experience of surgical treatment of single atrium. METHODS: From August 1984 to August 2004, there were 33 patients with single atrium in our study. Plastic surgery for mitral valves were performed for 30 cases with mitral insufficiency. Plastic surgery for tricuspid valves were performed for 18 cases with tricuspid valve insufficiency. There were 3 cases only with complete absence of atrial septum. There were 14 cases with left superior vena cava. All new atrial septums were made with patches including 24 autologous pericardial patches and 9 terylene patches. Complicate abnormalities were corrected in the same time. Tow suture techniques were used in operations to prevent conductive system block, and plastic surgery for mitral valves were performed until the mitral valves were sufficiency. RESULTS: There weren't death and conductive system block after operation in the group. One case was low-grade mitral insufficiency and the others weren't mitral insufficiency. Twenty-five cases were followed up from 3 months to 11 years, and they could work and study normally. CONCLUSIONS: Single atrium should be operated as early as possible. The key of surgery is to prevent conductive system block, to properly correct mitral insufficiency and to drastically correct complicated abnormality. The new atrial septum should be made by patch and an autologous pericardial patch is the first selection.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Comunicação Interatrial/cirurgia , Insuficiência da Valva Mitral/cirurgia , Insuficiência da Valva Tricúspide/cirurgia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
14.
Zhonghua Wai Ke Za Zhi ; 44(18): 1232-4, 2006 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-17147878

RESUMO

OBJECTIVE: To evaluate the indication and operative program of ventricular septal defect with pulmonary atresia (VSD-PA). METHODS: From June 1984 to March 2005, there were 32 patients with VSD-PA, which underwent 33 operations. Among them, 15 were males and 17 were females. The ages ranged from 6 months to 9 years. There were 9 patients with aortopulmonary collateral arteries. The operations included central aorta-pulmonary shunts 3 cases, one stage complete repair 27 cases and one stage unifocalization with VSD open 2 cases. RESULTS: There were early 5 death including one death after aorta-pulmonary shunt and 4 deaths after one stage complete repair. The causes of death were severe low cardiac output (2 patients), respiratory function failure (1 patient), multiorgan function failure (1 patient) and severe infect (1 patient). Twenty-one patients were followed up from 3 months to 15.5 years. Heart function (NYHA) was class I or II in 19 cases and class III or IV in 2 cases. CONCLUSIONS: The operative indication and methods mainly depend on the developing of pulmonary arteries and aortopulmonary collateral arteries. Completely surgical repair of patients with VSD-PA can be achieved with acceptable mortality.


Assuntos
Procedimentos Cirúrgicos Cardiovasculares/métodos , Comunicação Interventricular/cirurgia , Atresia Pulmonar/cirurgia , Criança , Pré-Escolar , Feminino , Seguimentos , Comunicação Interventricular/complicações , Humanos , Lactente , Masculino , Atresia Pulmonar/complicações , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
15.
Asian Cardiovasc Thorac Ann ; 14(3): 183-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16714692

RESUMO

Pulsatile pulmonary blood flow plays an important role in regulating shear-stress-mediated release of endothelium-derived nitric oxide and endothelin-1, and it reduces pulmonary vascular resistance by passive capillary recruitment. The aim of this study was to demonstrate changes in pulmonary capillary structure and endothelial function induced by the chronic nonpulsatile flow of the Fontan circulation. A canine model with nonpulsatile flow in the right lung was established, and sacrificed 3 months later. Compared to the left lung, wall thickness of the pulmonary arterioles was thinner, endothelin-1 expression was weaker, endothelial nitric oxide synthase activity was stronger, and there was a good correlation between the histomorphometric and immunohistochemical findings. These data indicate that long-term nonpulsatile flow can lead to endothelial dysfunction, which may be involved in distention and vascular structure remodeling due to the increase in pulmonary vascular resistance; but it also can lead to increased patency of the arteriovenous shunt, which might be at least partly involved in pulmonary arteriovenous fistula development and exercise limitation after the Fontan operation.


Assuntos
Endotélio Vascular/fisiopatologia , Técnica de Fontan , Pulmão/irrigação sanguínea , Circulação Pulmonar , Animais , Cães , Endotelina-1/metabolismo , Feminino , Masculino , Microcirculação , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Fluxo Sanguíneo Regional
16.
Zhonghua Wai Ke Za Zhi ; 43(22): 1437-40, 2005 Nov 15.
Artigo em Chinês | MEDLINE | ID: mdl-16318808

RESUMO

OBJECTIVE: To evaluate the indication and operative program of complete repair of tetralogy of Fallot with major aortopulmonary collateral arteries (TOF-MAPCA). METHODS: From January 2000 to May 2004, 9 patients with TOF-MAPCA including 5 patients with pulmonary atresia underwent complete surgical repair, 6 of them were male and 3 were female. The ages ranged from 3 to 9 years. All patients underwent corrected operations with moderate hypothermia and cardiopulmonary bypass. Transcatheter occlusion of MAPCA was performed in 5 patients just before corrected operation. Ligation of MAPCA was performed in 1 patient in the same time of cardiac corrected operation. Midline one-stage complete unifocalization and repair were performed in 3 patients with pulmonary atresia. RESULTS: There was one early death. The cause of death was spinal cord hemorrhage. There was no death then. Eight patients were followed up from 3 month to 4 years. Heart function (NYHA) was class I or II in 7 patients and III in 1 patient. CONCLUSIONS: Completely surgical repair of patients with TOF-MAPCA should be performed as early as possible, which can achieve with satisfactory results by transcatheter occlusion of MAPCA or one-stage unifocalization.


Assuntos
Aorta Torácica , Procedimentos Cirúrgicos Cardiovasculares/métodos , Artéria Pulmonar , Tetralogia de Fallot/cirurgia , Aorta Torácica/anormalidades , Aorta Torácica/cirurgia , Criança , Pré-Escolar , Circulação Colateral , Feminino , Seguimentos , Humanos , Masculino , Artéria Pulmonar/anormalidades , Artéria Pulmonar/cirurgia , Tetralogia de Fallot/complicações , Resultado do Tratamento
17.
Zhonghua Wai Ke Za Zhi ; 43(10): 647-9, 2005 May 15.
Artigo em Chinês | MEDLINE | ID: mdl-16008934

RESUMO

OBJECTIVE: To study the effects of inhaled nitric oxide (NO) on pulmonary vascular resistance in patients after total cavopulmonary connection (TCPC). METHODS: Fifty-two patients after TCPC were evaluated, of them 24 patients were administered with inhaled nitric oxide in the early postoperative period. The cardiac index (CI) and pulmonary vascular resistance (PVR) were compared before and after inhaled NO. RESULTS: In experimental group, after inhaled NO, partial pressure of oxygen in artery/fraction of inspired oxygen increased from 161 +/- 17 to 193 +/- 23 (t = 2.75, P < 0.01); CI from (2.86 +/- 0.24) L.min(-1).m(-2) to (3.13 +/- 0.22) L.min(-1).m(-2) (t = 2.25, P < 0.05); PVR decreased from (4.2 +/- 0.5) U/m(2) to (3.8 +/- 1.4) U/m(2) (t = 2.29, P < 0.05); central venous pressure (CVP) from (17.0 +/- 1.8) mm Hg to (15.0 +/- 1.1) mm Hg, decreased 11.7%. Compared with the control group, respirator time decreased from (86 +/- 27) h to (54 +/- 18) h (t = 2.29, P < 0.05); ICU time from (6 +/- 2) d to (4 +/- 2) d (t = 2.32, P < 0.05); But hydrothorax drainage and length of stay had no significant difference. CONCLUSIONS: Though inhaled NO, there is no significant long-term effects in patients after TCPC, but it may play an important role in the management of low cardiac output syndrome and high cava pressure caused by reactive elevated pulmonary vascular resistance in the early postoperative period of TCPC.


Assuntos
Derivação Arteriovenosa Cirúrgica/métodos , Óxido Nítrico/uso terapêutico , Artéria Pulmonar/cirurgia , Vasodilatadores/uso terapêutico , Veias Cavas/cirurgia , Administração por Inalação , Adolescente , Adulto , Débito Cardíaco/efeitos dos fármacos , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Óxido Nítrico/administração & dosagem , Período Pós-Operatório , Artéria Pulmonar/fisiologia , Fatores de Tempo , Resistência Vascular/efeitos dos fármacos , Vasodilatadores/administração & dosagem
18.
Zhonghua Wai Ke Za Zhi ; 42(16): 961-4, 2004 Aug 22.
Artigo em Chinês | MEDLINE | ID: mdl-15363229

RESUMO

OBJECTIVE: To summarize the experience of surgical treatment of secundum atrial septal defects in adults over 30 years old. METHODS: There were 469 patients with secundum atrial septal defects in our study (male 144, female 325; ages 30-68, mean 38.6 years old). There were 105 cases with pulmonary hypertension and 458 cases with arrhythmia in the group. Surgical closure of defects were performed in all patients. Surgical closure of 358 cases were done by patches including 305 autologous pericardial patches. The low dose (6 x 10(-6)) nitric oxide inhalation was used in 25 postoperative patients with pulmonary hypertension. Right sided maze procedures were done in 5 cases with atrial fibrillation. RESULTS: Surgical mortality was 0.6% (3 cases), the others were healed. In the group, there were 180 cases with arrhythmia, 27 cases with left ventricular function amyoplasia, 28 cases with low cardiac output syndrome, 12 cases in secondary operation for bleeding and 1 case with air-embolism. The level of mean pulmonary artery pressure of 25 postoperative patients with pulmonary hypertension inhaled nitric oxide was down 28.5%. After right sided maze procedures were done in 5 cases with atrial fibrillation, atrial fibrillation disappeared. 352 cases were followed up from 3 months to 20 years (mean 5.6 years). Twenty-nine cases were in class I-II of cardiac function, and the others were better than class I of cardiac function. CONCLUSIONS: Atrial septal defects in adult should be operated as early as possible. When patch is needed, an autologous pericardial patch is the first selection. Inhaled nitric oxide is an effective method to postoperative pulmonary hypertension. The maze operation should be performed for atrial septal defect with atrial fibrillation while the surgical closure of defect was done. During and after operation, much attention should be paid to preventing and curing arrhythmia and protecting and supporting left heart function.


Assuntos
Comunicação Interatrial/cirurgia , Administração por Inalação , Adulto , Fatores Etários , Idoso , Fibrilação Atrial/cirurgia , Fatores Relaxantes Dependentes do Endotélio/uso terapêutico , Feminino , Humanos , Hipertensão Pulmonar/complicações , Hipertensão Pulmonar/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/uso terapêutico , Complicações Pós-Operatórias/tratamento farmacológico , Estudos Retrospectivos
19.
Zhonghua Wai Ke Za Zhi ; 42(8): 462-4, 2004 Apr 22.
Artigo em Chinês | MEDLINE | ID: mdl-15144639

RESUMO

OBJECTIVE: To summarize the experience in surgical treatment of residual shunt after repair of ventricular septal defect and investigate the position of the residual shunts. METHODS: Between January 1979 and May 2003, re-operations on residual shunt after repair of ventricular septal defect were performed in 37 patients with congenital heart disease including ventricular septal defect, tetralogy of Fallot, double outlet right ventricle in 19, 17 and 1 patients, respectively. It accounted for 0.21% (37/18000) of open heart operations performed during these years. The patients included 26 males and 11 females with age from 3 months to 53 years (mean 16 +/- 12 years). The residual shunt was diagnosed by postoperative murmur and echocardiography. Twenty-six cases were repaired with patch and 11 cases were closed directly with mattresses sutures. RESULTS: Two patients (2/37, 5%) died within 48 hrs postoperatively. The results in other 35 patients followed up after surgery from 3 months to 15 years were satisfactory. CONCLUSIONS: Most of the residual shunts occurred in base of septal leaflet of tricuspid valve, the second and the first transfer suture respectively. Effects of reoperations on residual shunts were satisfactory.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Dupla Via de Saída do Ventrículo Direito/cirurgia , Comunicação Interventricular/cirurgia , Tetralogia de Fallot/cirurgia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/cirurgia , Reoperação , Estudos Retrospectivos
20.
Zhonghua Wai Ke Za Zhi ; 40(9): 679-81, 2002 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-12411139

RESUMO

OBJECTIVE: To study the changes of calcitonin gene-related peptide (CGRP) in patients who underwent total cavopulmonary connection (TCPC) and to assess the effects of non-pulsatile blood flow on the secretion function of the lung. METHODS: Twenty-six patients were divided into 2 groups: study group, 13 patients who underwent extracardiac TCPC, and control group, 13 patients who underwent definitive repair for ventricular septal or atrial septal defect. Blood samples for measurement of CGRP were obtained preoperatively, postoperatively or in the follow-up period. Cardiac index (CI) and pulmonary vascular resistance (PVR) were measured by cardiac catheter. RESULTS: The plasma level of CGRP was significantly higher in the study group than in the control group. CGRP was negatively correlated with PVR (r = -0.99, t = 9.82, P < 0.05), and positively correlation with CI (r = 0.98, t = 6.95, P < 0.05). CONCLUSIONS: After total right heart bypass, the non-pulsatile blood flow in pulmonary circulation may stimulate the lung to secrete CGRP, leading to the decrease of PVR and improve early postoperative recovery.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Técnica de Fontan , Cardiopatias Congênitas/cirurgia , Circulação Pulmonar , Adolescente , Adulto , Criança , Pré-Escolar , Cardiopatias Congênitas/fisiopatologia , Humanos , Resistência Vascular
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