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1.
J Exp Bot ; 74(17): 5236-5254, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37246636

RESUMO

Plant non-specific lipid transfer proteins (nsLTPs) are small, cysteine-rich proteins that play significant roles in biotic and abiotic stress responses; however, the molecular mechanism of their functions against viral infections remains unclear. In this study, we employed virus-induced gene-silencing and transgenic overexpression to functionally analyse a type-I nsLTP in Nicotiana benthamiana, NbLTP1, in the immunity response against tobacco mosaic virus (TMV). NbLTP1 was inducible by TMV infection, and its silencing increased TMV-induced oxidative damage and the production of reactive oxygen species (ROS), compromised local and systemic resistance to TMV, and inactivated the biosynthesis of salicylic acid (SA) and its downstream signaling pathway. The effects of NbLTP1-silencing were partially restored by application of exogenous SA. Overexpressing NbLTP1 activated genes related to ROS scavenging to increase cell membrane stability and maintain redox homeostasis, confirming that an early ROS burst followed by ROS suppression at the later phases of pathogenesis is essential for resistance to TMV infection. The cell-wall localization of NbLTP1 was beneficial to viral resistance. Overall, our results showed that NbLTP1 positively regulates plant immunity against viral infection through up-regulating SA biosynthesis and its downstream signaling component, NONEXPRESSOR OF PATHOGENESIS-RELATED 1 (NPR1), which in turn activates pathogenesis-related genes, and by suppressing ROS accumulation at the later phases of viral pathogenesis.


Assuntos
Nicotiana , Vírus do Mosaico do Tabaco , Nicotiana/metabolismo , Vírus do Mosaico do Tabaco/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ácido Salicílico/metabolismo , Doenças das Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
Scand J Gastroenterol ; 58(1): 34-37, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35868004

RESUMO

Objective: To evaluate the value of new gastric cancer screening score system for risk assessment of gastric precancerous lesions.Methods: A total of 520 patients were enrolled after the examination of endoscopy at Endoscopy Center, Department of Gastroenterology, from June 2018 to December 2021. The patients were divided into three groups according to age, gender, serum helicobacter pylori antibody test, pepsinogen I (PGI), pepsinogen II (PGII), pepsinogen I/II ratio (PGR) and gastrin-17 test results before endoscopy: Group A defined as low-risk group (0-11 points), Group B defined as middle-risk group (12-16 points), Group C defined as high-risk group (17-23 points). The detection rates of gastric cancer and atrophic gastritis in three groups were analyzed. According to the range and degree of atrophy/intestinal metaplasia, patients were divided into five groups on the basis of OLGA/OLGIM staging system. The levels of PG I, PG II and PGR were compared between different groups, and the correlation between new gastric cancer screening score system and OLGA/OLGIM staging system were evaluated. Statistical analysis was accomplished by ANOVA, chi-square test and Gamma coefficient analysis.Results: A total of 520 patients were enrolled. 268 patients were classified into group A,222 patients into group B and 30 patients into group C, respectively. According to the pathological results, 281 cases were non-atrophic gastritis, 230 cases atrophic gastritis and 9 cases gastric cancer. For OLGA staging system, 281 patients were divided into stage-0 group, 121 patients into stage-I group, 72 patients into stage-II group, 33 patients into stage-III group and 13 patients into stage-IV groups. The PGI and PGR level correlated inversely with the rising OLGA stages (F = 3.028, p = .016, F = 6.036, p < .001). For OLGIM staging system, 252 patients were divided into stage-0 group, 137 patients into stage-I group, 80 patients into stage-II group, 36 patients into stage-III group and 15 patients into stage-IV group. The PGR level correlated inversely with the rising OLGIM stages (F = 3.466, p=.007). The detection rates of gastric cancer and atrophic gastritis in Group C were much higher than other groups. (X2 = 14.727, p < .001; X2 = 51.280, p < .001). Gamma coefficient analysis showed significant correlations between OLGA/OLGIM and the new gastric cancer screening score system (p < .001).Conclusions: The new gastric cancer screening score system is closely linked with histological OLGA/OLGIM staging system in the risk assessment of gastric precancerous lesions. The role of new gastric cancer screening score system in future gastric precancerous lesions screening and high risk population identifying was promising.


Assuntos
Gastrite Atrófica , Infecções por Helicobacter , Helicobacter pylori , Lesões Pré-Cancerosas , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patologia , Pepsinogênio A , Detecção Precoce de Câncer , Medição de Risco/métodos , Gastrite Atrófica/diagnóstico , Gastrite Atrófica/patologia , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/patologia , China , Metaplasia , Infecções por Helicobacter/complicações , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/epidemiologia
3.
Sensors (Basel) ; 21(3)2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33530423

RESUMO

The super-resolution method has been widely used for improving azimuth resolution for radar forward-looking imaging. Typically, it can be achieved by solving an undifferentiable L1 regularization problem. The split Bregman algorithm (SBA) is a great tool for solving this undifferentiable problem. However, its real-time imaging ability is limited to matrix inversion and iterations. Although previous studies have used the special structure of the coefficient matrix to reduce the computational complexity of each iteration, the real-time performance is still limited due to the need for hundreds of iterations. In this paper, a superfast SBA (SFSBA) is proposed to overcome this shortcoming. Firstly, the super-resolution problem is transmitted into an L1 regularization problem in the framework of regularization. Then, the proposed SFSBA is used to solve the nondifferentiable L1 regularization problem. Different from the traditional SBA, the proposed SFSBA utilizes the low displacement rank features of Toplitz matrix, along with the Gohberg-Semencul (GS) representation to realize fast inversion of the coefficient matrix, reducing the computational complexity of each iteration from O(N3) to O(N2). It uses a two-order vector extrapolation strategy to reduce the number of iterations. The convergence speed is increased by about 8 times. Finally, the simulation and real data processing results demonstrate that the proposed SFSBA can effectively improve the azimuth resolution of radar forward-looking imaging, and its performance is only slightly lower compared to traditional SBA. The hardware test shows that the computational efficiency of the proposed SFSBA is much higher than that of other traditional super-resolution methods, which would meet the real-time requirements in practice.

4.
Opt Express ; 22(15): 17897-907, 2014 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-25089410

RESUMO

Considering the limited pixel number and large pixel size of common display panel, the captured elemental images (EIs) array of high density pixels cannot be reconstructed sufficiently in the display process of integral imaging, because of matched display requirement. To solve this problem, this paper presents a novel approach to improve integral imaging resolution by designing a coded sub-pixel mask on common display panel. Specifically, multi-pixels in the captured EIs are displayed in a pixel in the common display panel with time multiplexing along with the corresponding aperture switched on/off of the coded sub-pixel mask periodically, in which the resolution of the reconstructed image is determined by the coded aperture size of the sub-pixel mask rather than the pixel size of the display panel. Then, the mapping relationship between the displayed pixel and the position of the switched on aperture of the coded sub-pixel mask is established theoretically. Computational reconstruction and optical experimental results show that this method can match the pixel number of the captured EIs with that of the display panel and the resolution of integral imaging can be improved significantly.

5.
Opt Express ; 22(17): 20757-69, 2014 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-25321279

RESUMO

To solve the pseudoscopic problem, we propose a one-step integral imaging system with negative refractive index materials, which can avoid the deterioration in resolution inherent to the optical or digital two-step processes. Specifically, the proposed method is based on the novel feature of negative refractive index materials, bending light to a negative angle relative to the surface normal. The pseudoscopic imaging property of the negative refractive index material slab is theoretically investigated. For formation of orthoscopic reconstructed images, the matching condition of the negative index lens array and the positive index lens array is deduced. Two types of conceptual prototypes of integral imaging system with negative refractive index materials are designed. Experimental results show the validity of the proposed method. To the best of our knowledge, this is the first time to explore the application of negative index materials in eliminating the pseudoscopic effect in integral imaging.

6.
Appl Opt ; 53(25): 5654-9, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25321360

RESUMO

A method for improving the viewing quality of integral imaging (II) is proposed, based on using an aperture-tunable lens array (LA). The proposed method uses a liquid crystal (LC) panel without a backlighting unit to tune the aperture of an LA dynamically. The shape and transmittance of the aperture can be controlled arbitrarily by programming the state of the pixels on the LC panel. Adding the temporal multiplexing technique, the viewing quality can be improved by the after-image effect of the human eye. Moreover, the relationships between the lateral resolution and the aperture tuning pattern and the depth of field and the aperture tuning pattern are derived, respectively. The product of the depth of field, the lateral resolution squared, and the lateral viewing range is proposed as a new figure of merit for an II system. Experimental results show the validity of the proposed method.

7.
J Adv Res ; 57: 15-42, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37142184

RESUMO

BACKGROUND: Crops are constantly attacked by various pathogens. These pathogenic microorganisms, such as fungi, oomycetes, bacteria, viruses, and nematodes, threaten global food security by causing detrimental crop diseases that generate tremendous quality and yield losses worldwide. Chemical pesticides have undoubtedly reduced crop damage; however, in addition to increasing the cost of agricultural production, the extensive use of chemical pesticides comes with environmental and social costs. Therefore, it is necessary to vigorously develop sustainable disease prevention and control strategies to promote the transition from traditional chemical control to modern green technologies. Plants possess sophisticated and efficient defense mechanisms against a wide range of pathogens naturally. Immune induction technology based on plant immunity inducers can prime plant defense mechanisms and greatly decrease the occurrence and severity of plant diseases. Reducing the use of agrochemicals is an effective way to minimize environmental pollution and promote agricultural safety. AIM OF REVIEW: The purpose of this workis to offer valuable insights into the current understanding and future research perspectives of plant immunity inducers and their uses in plant disease control, ecological and environmental protection, and sustainable development of agriculture. KEY SCIENTIFIC CONCEPTS OF REVIEW: In this work, we have introduced the concepts of sustainable and environment-friendly concepts of green disease prevention and control technologies based on plant immunity inducers. This article comprehensively summarizes these recent advances, emphasizes the importance of sustainable disease prevention and control technologies for food security, and highlights the diverse functions of plant immunity inducers-mediated disease resistance. The challenges encountered in the potential applications of plant immunity inducers and future research orientation are also discussed.


Assuntos
Praguicidas , Imunidade Vegetal , Produtos Agrícolas , Resistência à Doença , Doenças das Plantas/prevenção & controle
8.
Materials (Basel) ; 16(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36614610

RESUMO

Silt in the Yellow River alluvial plain is widely spread, but its uniform particle size and high roundness make it unsuitable as a subgrade filling material, while titanium gypsum (TG) is an industrial solid waste in Shandong Province, not only occupying land resources but also causing water and air pollution. In order to improve the engineering performance of silt, reduce the pollution of solid waste titanium gypsum to the environment and reduce the engineering cost, considering the engineering characteristics of titanium gypsum, it was combined in specific amounts with cement and lime to create a titanium gypsum-based stabilizer (TS) in this study. The effect of curing conditions and TS content on silt improvement was studied through laboratory experiments. The mechanical properties of the stabilized silt were investigated by unconfined compression test (UCT), and the mineral composition and pore structure were analyzed by scanning electron microscopy (SEM) test, X-ray diffraction (XRD) test, and mercury injection pore (MIP) test. The test results show that TS could effectively improve the unconfined compressive strength of silt, and the strength of stabilized silt gradually increases with the curing period and TS content. In terms of the porosity, it decreases with the increase of the curing period and TS content. From the microstructure perspective, this is mainly due to the formation of ettringite and C-S-H during the stabilization of silt by TS.

9.
Zhonghua Yi Xue Za Zhi ; 91(24): 1659-62, 2011 Jun 28.
Artigo em Chinês | MEDLINE | ID: mdl-21914311

RESUMO

OBJECTIVE: To investigate the effects of exercise therapy at the intensity of anaerobic threshold (AT) for exercise tolerance in patients with chronic stable coronary artery disease. METHODS: Forty-three patients with chronic stable coronary artery disease (3 patients after coronary arterial bypass graft (CABG) surgery, 22 patients with old myocardial infarction and 18 unstable angina pectoris undergoing successful percutaneous coronary intervention (PCI) finished twice cardiopulmonary exercise test (CPET) and followed their rehabilitation program for 3 months. Thirty-two patients finished their aerobic exercise therapy based on their individual anaerobic thresholds while 11 patients had no exercise therapy. RESULTS: The heart rate at AT intensity (97 ± 9/min) was lower than their traditional minimal target heart rate (112 ± 7/min) and lower than heart rate (115 ± 11/min) at ischemic threshold post-CPET. The O(2) consumption (10.7 ± 2.4 to 12.6 ± 2.9 ml×min(-1)×kg(-1)) (P = 0.04) and workload (37 ± 18 to 47 ± 13 J/s) (P = 0.04) at AT level and the O(2) consumption (15.3 ± 3.1 to 20.6 ± 4.2 ml×min(-1)×kg(-1), P = 0.02) and workload(68 ± 12 and 87 ± 14 J/s, P = 0.01) at peak level markedly increased after 3 months in the exercise group. And the O(2) consumption (15.3 ± 2.9 to 16.2 ± 3.1 ml×min(-1)×kg(-1)) and workload (65 ± 13 to 73 ± 16 J/s) at peak level mild increased after 3 months in the non-exercise group, but their O(2) consumption (11.0 ± 2.7 to 11.3 ± 2.8 ml×min(-1)×kg(-1)) and workload (38 ± 11 to 37 ± 9 J/s) at AT level had no obvious change. CONCLUSION: AT exercise intensity was lower than ischemic threshold post-CPET. Exercise therapy at the intensity of anaerobic threshold can improve oxygen capacity and exercise tolerance.


Assuntos
Limiar Anaeróbio , Doença da Artéria Coronariana/metabolismo , Doença da Artéria Coronariana/reabilitação , Terapia por Exercício , Oxigênio/metabolismo , Idoso , Teste de Esforço , Tolerância ao Exercício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Zhonghua Yi Xue Za Zhi ; 91(38): 2678-82, 2011 Oct 18.
Artigo em Chinês | MEDLINE | ID: mdl-22321976

RESUMO

OBJECTIVE: To explore the effects of aerobic exercise on exercise tolerance in patients with chronic heart failure (CHF). METHODS: A total of 50 CHF patients with left ventricular ejection fraction (LVEF) < 49% by echocardiography were enrolled. And they were randomly divided into exercise group (n = 25) and non-exercise group (n = 25). Cardiopulmonary exercise testing (CPET) was performed. The patients of exercise group underwent an aerobic exercise program in which exercise intensity was decided by anaerobic threshold (AT) before 10 J/s while those of non-exercise group performed daily activities. After 6 sessions of supervised aerobic exercise, the home-based aerobic exercise training began. CPET was re-examined 3 months later. RESULTS: The VO(2) AT, VO(2) peak, Load AT, Load peak, peak VO(2)/HR and VE/VCO(2) slope at baseline were similar between exercise group and non-exercise group (P > 0.05). The VO(2) AT, VO(2) peak, Load AT, Load peak and peak VO(2)/HR in patients of exercise group were increased compared with baseline, The differences between baseline and 3 months later expressed as ΔVO(2) AT, ΔVO(2) peak, ΔLoad AT, ΔLoad peak, Δpeak VO(2)/HR and ΔVE/VCO(2) slope, The differences of ΔVO(2) AT, ΔVO(2) peak, ΔLoad AT, ΔLoad peak and Δpeak VO(2)/HR between two groups were statistically significant [ΔVO(2) AT: 2.8 (1.2 - 3.5) ml×kg(-1)×min(-1) vs -0.3 (-2.8 - 0.1) ml×kg(-1)×min(-1), P < 0.01; ΔVO(2) peak: 3.4 (1.8 - 4.6) ml×kg(-1)×min(-1) vs -0.5 (-1.4 - 0.3) ml×kg(-1)×min(-1), P < 0.01; ΔLoad AT:15.0 (2.5 - 22.5) J/s vs 0.5(-4.2 - 3.8) J/s, P < 0.01; ΔLoad peak: 15.0 (1.3 - 25.0) J/s vs 0.0 (-8.8 - 15.0) J/s, P < 0.05; Δpeak VO(2)/HR: 2.3 (0.0 - 4.0) ml×kg(-1)×beat(-1) vs -0.1 (-0.7 - 1.2) ml×kg(-1)×beat(-1), P < 0.01]. The difference of ΔVE/VCO(2) slope was not statistically significant [-2.3 (-12.2 - 1.8) vs 1.0 (-0.4 - 2.6), P > 0.05]. CONCLUSION: After 3 months of aerobic exercise, exercise capacity may improve in the CHF patients.


Assuntos
Tolerância ao Exercício , Exercício Físico , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/reabilitação , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio
11.
Zhonghua Xin Xue Guan Bing Za Zhi ; 39(8): 700-5, 2011 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-22169414

RESUMO

OBJECTIVE: To observe the effects of aerobic exercise on cardiac output during exercise in patients with chronic heart failure (CHF). METHODS: A total of 50 CHF patients (echocardiography measured left ventricular ejection fraction < 0.49) were enrolled in the study and randomly divided into aerobic exercise group (n = 25) and control group (n = 25). Cardiopulmonary exercise testing (CPET) was performed. Patients of aerobic exercise group underwent aerobic exercise according to aerobic exercise prescription and exercise intensity is decided by anaerobic threshold before 10 J/s (1 minute before) of the oxygen consumption. After 6 supervised aerobic exercise training sessions in the hospital, patients were asked to perform the home-based aerobic exercise training. Patients in control group were required to maintain daily physical activities. CPET were reviewed 3 months later. RESULTS: Cardiac output (CO), peak CO, peak cardiac power output (peak CPO), resting heart rate (HR), heart rate at AT (HRAT), HR peak, resting mean arterial pressure (MAP), peak MAP at baseline were similar between aerobic exercise group and control [(4.2 ± 2.0) L/min vs. (3.3 ± 1.0) L/min, (6.2 ± 2.7) L/min vs. (5.2 ± 1.8) L/min, (1.8 ± 2.9) L/min vs. (2.0 ± 1.8) L/min, (1.3 ± 0.5) J/s vs. (1.2 ± 0.5) J/s, (76.8 ± 13.5) beats/min vs. (73.4 ± 11.9) beats/min, (91.5 ± 11.3) beats/min vs. (92.6 ± 12.4) beats/min, (106.0 ± 12.9) beats/min vs. (108.3 ± 17.4) beats/min, (80.8 ± 9.9) mm Hg (1 mm Hg = 0.133 kPa) vs. (87.6 ± 13.3) mm Hg, (98.8 ± 12.4) mm Hg vs. (102.7 ± 13.9) mm Hg, all P > 0.05]. Compared to baseline, CO, peak CO, peak CPO, HR, HRAT, HR peak, MAP, peak MAP after 3 months were similar between aerobic exercise group and control (all P > 0.05). The differences between baseline and 3 months later expressed as ΔCO, Δpeak CO, Δpeak CPO, ΔHR, ΔHRAT, ΔHR peak, ΔMAP, Δpeak MAP were also similar between aerobic exercise group and control group [(-0.7 ± 2.4) L/min vs. (0.7 ± 2.0) L/min, (1.1 ± 2.6) L/min vs. (1.4 ± 2.1) L/min, (0.1 ± 3.7) L/min vs. (-0.2 ± 2.5) L/min, (0.2 ± 1.0) J/s vs. (0.2 ± 0.5) J/s, (-0.4 ± 7.6) beats/min vs. (1.9 ± 9.9) beats/min, (3.4 ± 11.3) beats/min vs. (-2.8 ± 7.6) beats/min, (8.9 ± 14.5) beats/min vs. (3.7 ± 14.4) beats/min, (1.5 ± 12.8) mm Hg vs. (-1.3 ± 11.1) mm Hg, (6.4 ± 18.9) mm Hg vs. (1.3 ± 12.3) mm Hg, all P > 0.05]. CONCLUSION: Three months aerobic exercise training did not improve cardiac output and related parameters during exercise in this cohort patients with CHF.


Assuntos
Terapia por Exercício , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Idoso , Pressão Sanguínea , Débito Cardíaco , Exercício Físico , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio
12.
Mol Plant Pathol ; 22(12): 1668-1687, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34553471

RESUMO

Systemic acquired resistance (SAR) is induced by pathogens and confers protection against a broad range of pathogens. Several SAR signals have been characterized, but the nature of the other unknown signalling by small metabolites in SAR remains unclear. Glutathione (GSH) has long been implicated in the defence reaction against biotic stress. However, the mechanism that GSH increases plant tolerance against virus infection is not entirely known. Here, a combination of a chemical, virus-induced gene-silencing-based genetics approach, and transgenic technology was undertaken to investigate the role of GSH in plant viral resistance in Nicotiana benthamiana. Tobacco mosaic virus (TMV) infection results in increasing the expression of GSH biosynthesis genes NbECS and NbGS, and GSH content. Silencing of NbECS or NbGS accelerated oxidative damage, increased accumulation of reactive oxygen species (ROS), compromised plant resistance to TMV, and suppressed the salicylic acid (SA)-mediated signalling pathway. Application of GSH or l-2-oxothiazolidine-4-carboxylic acid (a GSH activator) alleviated oxidative damage, decreased accumulation of ROS, elevated plant local and systemic resistance, enhanced the SA-mediated signalling pathway, and increased the expression of ROS scavenging-related genes. However, treatment with buthionine sulfoximine (a GSH inhibitor) accelerated oxidative damage, elevated ROS accumulation, compromised plant systemic resistance, suppressed the SA-mediated signalling pathway, and reduced the expression of ROS-regulating genes. Overexpression of NbECS reduced oxidative damage, decreased accumulation of ROS, increased resistance to TMV, activated the SA-mediated signalling pathway, and increased the expression of the ROS scavenging-related genes. We present molecular evidence suggesting GSH is essential for both local and systemic resistance of N. benthamiana to TMV through a differential modulation of SA and ROS.


Assuntos
Glutationa , Nicotiana , Doenças das Plantas/virologia , Vírus do Mosaico do Tabaco , Resistência à Doença , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ácido Salicílico/metabolismo , Nicotiana/metabolismo , Nicotiana/virologia
13.
Zhonghua Yi Xue Za Zhi ; 90(20): 1395-8, 2010 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-20646628

RESUMO

OBJECTIVE: To evaluate the cardiopulmonary exercise capacity in patients with chronic heart failure (CHF). METHODS: Cardiopulmonary exercise testing on bicycle ergometer was performed in 74 age, gender and BMI-matched patients. There were 37 patients with LVEF < 0.45 in CHF group and another 37 patients with LVEF > 0.50 in control group. VO(2)AT, VO(2)Peak, Load AT, Load peak and VE/VCO(2) slope were measured and compared. RESULTS: (1) VO(2)AT, VO(2)Peak, Load AT and Load peak were all significantly reduced in patients with CHF as compared with controls [VO(2)AT: (11.3 +/- 2.3) ml x kg(-1) x min(-1) vs (12.8 +/- 2.5) ml x kg(-1) x min(-1), P < 0.05; VO(2)peak: (15.2 +/- 4.3) ml x kg(-1) x min(-1) vs (17.3 +/- 3.9) ml x kg(-1) x min(-1), P < 0.05; Load AT: (25.2 +/- 18.8) J x s(-1) vs (45.6 +/- 18.7) J x s(-1), P < 0.01; Load peak: (54.9 +/- 22.5) J x s(-1) vs (80.3 +/- 21.6) J x s(-1), P < 0.01]; (2) VE/VCO(2) slope increased in patients with CHF as compared with controls [(36.7 +/- 6.7) vs (30.3 +/- 4.3), P < 0.01]; (3) None of VO(2)AT, VO(2), Peak Load AT, Load peak or VE/VCO(2) slope was correlated with LVEF [(r = 0.054, P > 0.05); (r = 0.03, P > 0.05); (r = 0.310, P > 0.05); (r = 0.174, P > 0.05); (r = -0.203, P > 0.05)]; VO(2)AT, VO(2)Peak, Load AT and Load peak were all correlated negatively with a higher NYHA grade [(r = -0.477, P < 0.01); (r = -0.591, P < 0.01); (r = -0.640, P < 0.01); (r = -0.672, P < 0.01)]; VE/VCO(2) slope correlated positively with a higher NYHA grade (r = 0.652, P < 0.01); None of VO(2)AT, VO(2)Peak, Load AT, Load peak or VE/VCO(2) slope was correlated with LVMI [r = 0.045, P > 0.05); (r = -0.017, P > 0.05); (r = -0.214, P > 0.05); (r = -0.123, P > 0.05); (r = 0.106, P > 0.05)]. CONCLUSION: (1) Cardiopulmonary exercise capacity is reduced in CHF patients. (2) None of VO(2)AT, VO(2)Peak, Load AT, Load peak and VE/VCO(2) slope is correlated with LVEF; VO(2)AT, VO(2)Peak, Load AT and Load peak all correlate negatively with the higher NYHA grade; VE/VCO(2) slope correlates positively with a higher NYHA grade; None of VO(2)AT, VO(2)Peak, Load AT, Load peak or VE/VCO(2) slope correlates with LVMI. An analysis of gas metabolism is a safe, accurate and scientific testing method of exercise tolerance.


Assuntos
Tolerância ao Exercício , Gases/metabolismo , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Idoso , Estudos de Casos e Controles , Doença Crônica , Feminino , Testes de Função Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória
14.
Yao Xue Xue Bao ; 44(12): 1416-20, 2009 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-21351480

RESUMO

The fluorescence spectroscopy and UV spectroscopy have been used to monitor the inclusion phenomena of VP-16 with beta-cyclodextrin (beta-CD), together with studies concerning the effects of reaction time, temperature and concentration on this behavior. The results show that the fluorescence intensity increased when VP-16 and beta-CD forming a 1 : 1 inclusion complex, which indicate that beta-CD has fluorescence sensitizing effect on the VP-16. At 22 degrees C, the inclusion constant was 2.63 x 10(5) L x mol(-1) at pH 7.0. VP-16 has maximum emission wavelength at 316 nm under the optimum conditions. According to this, the quantitative micro-detection method of VP-16 by fluorescence spectrometry was established. The linear regression equation was y = 1.107 89 x 10(70 x + 95.898 1, with a correlation coefficient of 0.999 9. The detection limit was 2.094 x 10(-7) mol x L(-1).


Assuntos
Etoposídeo/química , beta-Ciclodextrinas/química , Interações Medicamentosas , Concentração de Íons de Hidrogênio , Modelos Lineares , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Temperatura
15.
Zhonghua Yi Xue Za Zhi ; 88(26): 1820-3, 2008 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-19040016

RESUMO

OBJECTIVE: To investigate the safety and effects of early submaximal cardiopulmonary exercise test (CPET) and cardiac rehabilitation for patients with acute myocardial infarction (AMI) after percutaneous coronary intervention (PCI). METHODS: 94 patients with AMI after PCI were randomly divided into 2 groups: exercise group undergoing anaerobic rehabilitation training based on anaerobic threshold (AT) exercise prescription for 3 months, and control group, conducting exercise according to the needs of the patients themselves. Three months later, the exercise cardiopulmonary function was evaluated. RESULTS: In the first CPET 89 patients attained their anaerobic threshold (AT) and their heart rates were lower than their target heart rates following the exercise test. The oxygen consumption at the anaerobic threshold (VO2AT) 3 months later of the exercise group was [(12.6 +/- 2.9) ml x min(-1) x kg(1)], significantly greater and that before the exercise [(10.5 x 2.9) ml x min x kg(-1), P = 0.000]. The peak oxygen uptake (VO2 pea) 3 months of the exercise group was (20 +/- 4) ml x min(-1) x kg(-1), signficantly greater then that before exercise [(14 +/- 4) ml x min(-1) x kg(-1), P = 0.000]. The LAT 3 months of the exercise group was (42 +/- 16) J x s(-1), significantly higher than that before exercise p [(33 +/- 20) J x s(-1), P = 0.000]. The workload at peak level (Lpeak) 3 months of the exercise group was (89 +/- 14) J x s(-1) significantly greater than thatbefore exercise [(66 +/- 21) J x s(-1), P = 0.000]. And the VO2pea and Lpeak of 3 months later of the control group were [(19 +/- 4) ml x min(-l) x kg(-1)) and (80 +/- 14) J x s(-1)] respectively, both significantly higher than those before exercise [(14 +/- 4) ml x min(-1) x kg(-1) and (64 +/- 21) J x s(-1), both P = 0.000]. CONCLUSION: The early submaximal CPET and cardiac rehabilitation for patients with AMI after PCI are not only safe but also can improve their exercise capacity.


Assuntos
Angioplastia Coronária com Balão , Terapia por Exercício/métodos , Infarto do Miocárdio/terapia , Idoso , Limiar Anaeróbio , Teste de Esforço , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/reabilitação
16.
PLoS One ; 11(1): e0147423, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26808510

RESUMO

BACKGROUND: Cardiopulmonary exercise testing has been widely used to risk stratify patients with chronic heart failure (CHF). Peak oxygen consumption (peakVO2) was regarded as a powerful predictor of survival, as it is a surrogate for peak cardiac output (CO), which by most is considered the "true" measure of heart failure. Therefore, it is reasonable to hypothesize that CO is an even stronger predictor than peak VO2. The present study is aimed to investigate the prognostic value of peak cardiac power output (peak CPO) in comparison with peakVO2 in Chinese patients with CHF. METHODS: Participants provided written informed consent to participate in this study. Totally 129 patients with CHF underwent symptom-limited cardiopulmonary exercise testing (CPET), with mean age 59.1 ± 11.4 years, 87.6% male, 57.4% ischemic etiology, body mass index (BMI) 24.7 ± 3.7 kg/m(2) and LVEF 38 ± 9%. CO was measured using an inert gas rebreathing method. The primary endpoints are cardiac deaths. RESULTS: Over median 33.7-month follow-up, 19 cardiac deaths were reported. Among peak VO2,VE/VCO2 slope and Peak CPO, their area under ROC were 0.64, 0.67, 0.68, respectively (Ρ<0.05).The optimal thresholds for predicting cardiac deaths were peak VO2 ≤ 13.4 ml.kg(-1).min(-1), and VE/VCO2 slope ≥ 39.3 and peak CPO≤ 1.1 respectively by ROC analysis. Finally, in patients with a peak VO2 ≤ 13.4 ml.kg(-1).min(-1) those with peak CPO>1.1W had better survival than those with peak CPO ≤ 1.1W. However, by multivariate analysis adjusted for age, sex, BMI, resting heart rate, LVMI, LVEF, Peak CPO was not an independent predictor of cardiac deaths (P> 0.05). CONCLUSIONS: Peak CPO was not a predictor of cardiac death in Chinese CHF patients.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Testes de Função Cardíaca , Idoso , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
17.
Exp Ther Med ; 9(4): 1407-1412, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25780443

RESUMO

The minute ventilation/carbon dioxide production (VE/VCO2) slope has been widely demonstrated to have strong prognostic value in patients with chronic heart failure (CHF), and the risk of mortality is believed to increase when the VE/VCO2 slope is >32.8; however, there is little evidence concerning the prognostic value of the VE/VCO2 slope in Chinese patients. In the present study, the prognostic value of the VE/VCO2 slope was investigated in patients with CHF. A total of 258 subjects underwent symptom-limited cardiopulmonary exercise testing (CPET) and were divided into CHF (113 males and 16 females; LVEF <0.49) and control (106 males and 23 females) groups. The cardiac-related events over a median 33.7-month follow-up period subsequent to the CPET were evaluated using receiver operating characteristic curve analysis. The VE/VCO2 slope was significantly different between the CHF and control groups (P<0.001). The area under the curve (AUC) for the VE/VCO2 slope in predicting cardiac-related mortalities in the patients with CHF was 0.670 (P<0.05), and the sensitivity and specificity of the VE/VCO2 slope were 0.667 and 0.620, respectively. The optimal threshold of the VE/VCO2 slope for predicting cardiac-related mortalities in patients with CHF was ≥39.3. The AUC for the VE/VCO2 slope in predicting cardiac-related hospitalizations in patients with CHF was 0.682 (P<0.05), and the sensitivity and specificity of the VE/VCO2 slope were 0.631 and 0.778, respectively. The optimal threshold of the VE/VCO2 slope for predicting cardiac-related hospitalizations in patients with CHF was ≥32.9. In conclusion, ventilatory efficiency decreases in patients with CHF. The VE/VCO2 slope is a strong predictor of cardiac-related mortalities in the patients with CHF analyzed.

18.
Chin Med J (Engl) ; 125(3): 465-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22490404

RESUMO

BACKGROUND: There is no research, either at home or abroad, focusing on assessing the cardiopulmonary functional reserve and exercise tolerance in patients with pulmonary embolism (PE), but the benefits of early exercise are well recognized. The goals of this study were to assess cardiopulmonary functional reserve in treated PE patients using the inert gas rebreathing method of the cardiopulmonary exercise test (CPET), and to compare it with traditional methods. METHODS: CPET on the bicycle ergometer were performed in 40 patients with age, gender, body mass index, systolic blood pressure, and pulmonary function matched. The first group was the PE group composed of 16 PE patients (5 male, 11 female) who were given the standard antithrombotic therapy for two weeks. The second group was composed of 24 normal individuals (10 male, 14 female). Both groups were evaluated by cardiac ultrasound examination, 6-minute walking test (6MWT), and CPET. RESULTS: (1) Right ventricular systolic pressure (RVSP) in the PE group increased significantly compared to the control group, (34.81 ± 8.15) mmHg to (19.75 ± 3.47) mmHg (P < 0.01). But neither right atrial end-systolic diameter (RASD) nor right ventricular end-diastolic diameter (RVDD) in the PE patients had changed when compared with the controls. The 6-minute walk distance was significantly reduced in the PE patients compared with normal subjects, (447.81 ± 79.20) m vs. (513.75 ± 31.45) m (P < 0.01). Both anaerobic threshold oxygen consumption (VO(2)AT) and peak oxygen consumption (VO(2)peak) were significantly lower in patients with PE, while CO(2) equivalent ventilation (VE/VCO(2) slope) was higher; VO(2)AT (9.44 ± 3.82) ml×kg(-1)×min(-1) vs. (14.62 ± 2.93) ml×kg(-1)×min(-1) (P < 0.01) and VO2peak (12.26 ± 4.06) ml×kg(-1)×min(-1) vs. (23.46 ± 6.15) ml×kg(-1)×min(-1) (P < 0.01) and VE/VCO(2) slope 35.47 ± 6.66 vs. 26.94 ± 3.16 (P < 0.01). There was no significant difference in resting cardiac output (CO) between the PE and normal groups, whereas peak cardiac output (peak CO) and the difference between exercise and resting cardiac output (ΔCO) were both significantly reduced in the PE group; peak CO (5.97 ± 2.25) L/min to (8.50 ± 3.13) L/min (P < 0.01), ΔCO (1.29 ± 1.59) L/min to (3.97 ± 2.02) L/min (P < 0.01). (2) The 6-minute walk distance did not correlated with CPET except for the VO2 peak in patients with PE, r = 0.675 (P < 0.01). CONCLUSIONS: The cardiopulmonary functional reserve was reduced in patients with PE. CPET is an accurate, quantitative evaluation of cardiopulmonary functional reserve for PE patients.


Assuntos
Teste de Esforço/métodos , Tolerância ao Exercício/fisiologia , Embolia Pulmonar/terapia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Embolia Pulmonar/fisiopatologia
19.
Chin Med J (Engl) ; 124(16): 2485-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21933592

RESUMO

BACKGROUND: Impaired exercise capacity is one of the most common clinical manifestations in patients with chronic heart failure (CHF). The severity of reduced exercise capacity is an indicator of disease prognosis. The aim of the current study was to investigate the association between left heart size and mass with exercise capacity. METHODS: A total of 74 patients were enrolled in the study, with 37 having congestive heart failure (left ventricular ejection fraction (LVEF) < 0.45) and the other 37 with coronary heart disease (by coronary angiography) serving as the control group (LVEF > 0.55). Echocardiography and cardiopulmonary exercise test were performed. The multiply linear regression model was used to evaluate the association between echocardiogrphic indices and exercise capacities. RESULTS: The study showed that left ventricular end diastolic/systolic diameter (LVEDD/LVESD), left atrial diameter (LAD) and left ventricular mass index (LVMI) were significantly enlarged in patients with chronic heart failure compared with controls (P < 0.01). The VO(2)AT, Peak VO(2), Load AT, and Load Peak in chronic heart failure patients were also significantly reduced compared with controls (P < 0.05), VE/VCO(2) slope was increased in patients with chronic heart failure (P < 0.01). Multivariate linear regression analysis indicated that the patients' exercise capacity was significantly associated with the left heart size and mass, however, the direction and/or strength of the associations sometimes varied in chronic heart failure patients and controls. Load AT correlated negatively with LVEDD in chronic heart failure patients (P = 0.012), while Load AT correlated positively with LVEDD in control patients (P = 0.006). VE/VCO(2) slope correlated positively with LAD (B = 0.477, P < 0.0001) in chronic heart failure patients, while the VE/VCO(2) slope correlated negatively with LAD in control patients (P = 0.009). CONCLUSION: The study indicates that the size of LVEDD and LAD are important determinants of exercise capacity in patients with CHF, which may be helpful to identify exercise tolerance for routine monitoring of systolic heart failure.


Assuntos
Volume Cardíaco/fisiologia , Tolerância ao Exercício/fisiologia , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Idoso , Ecocardiografia , Teste de Esforço , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia
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