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Purpose To take the advantages of terrain-adaptive capability of legged platform and fast-moving ability of wheeled platform, this paper aims to design a leg-wheel mobile platform for obstacle surmounting and analyze the feasibility and locomotivity of different moving modes. Design/methodology/approach The platform consists of six leg-wheel units. Each of the units has a close-chain mechanical leg and an actuated wheel at the end of the leg. The platform moves with two modes: legged mode and leg-wheel composite mode. The legged mode achieves high mobility driven by crank motors, while the leg-wheel composite mode achieves obstacle-surmounting ability actuated by crank motors and pitch link motors and obtains high efficiency with the hub motors. The gait planning in different modes has been carried out and the obstacle-surmounting capacity has been analyzed. Findings Based on the results of kinematic analysis and gait planning of the close-chain leg-wheel platform, the high mobility and efficiency obstacle-surmounting ability are demonstrated with the two movement modes. The feasibility of the design and the performance of the mobile platform is verified with the prototype experiment. The results of this paper show that the platform possesses good obstacle-surmounting capability. Originality/value The work presented in this paper is a novel exploration to design a close-chain leg mechanism and with an actuated wheel in series. The close-chain leg mechanism has the advantages of high leg lift and single degree of freedom characteristics, which makes the platform obtain the ability of obstacle-surmounting.

OBJECTIVE Cardiopulmonary bypass (CPB) produces an inflammatory response associated with pulmonary dysfunction. P38 mitogen-activated protein kinase (P38MAPK) have been shown to mediate pulmonary inflammatory response after CPB, we examined the effect of SB203580, a specific p38 MAPK inhibitor, on CPB-induced pulmonary inflammatory response. METHODS Sprague-Dawley rats (n=54) were randomized into three groups (each n=18): (1) S group, rats underwent sham CPB; (2) CPB group, rats underwent CPB; (3) SB group, rats underwent CPB plus pretreatment with SB203580 (10 mg/kg, i.v., 30 min before CPB). The lung samples were collected after 10 min, 60 min, and 150 min lung reperfusion (each n=6) in CPB group and SB group, and after 70 min, 120 min, and 210 min observation in S group as the control. RESULTS The level of lung phospho-IkappaBalpha, nuclear factor (NF)-kappaB activity and activating protein (AP)-1 activity in CPB group was increased than S group. CPB resulted in increased pulmonary tissue tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta expression and production, increased pulmonary inflammatory response. The in vivo administration of SB203580 prevented up-regulation of lung-phosphorylated p38 MAP kinase, decreased pulmonary tissue level of proinflammatory cytokines expression and production, and reduced lung inflammation. CONCLUSIONS These findings suggested that (1) p38 MAP kinase activation is one of the important aspects of the signaling event that mediate the release of TNF-alpha and IL-1beta and contributes to CPB-induced pulmonary inflammatory response, (2) SB203580 selectively inhibiting p38 MAP kinase activation efficaciously reduces pulmonary inflammatory response after CPB, and (3) p38 MAP kinase influence the activation of NF-kappaB in the lung during and after CPB.

The best age for the arterial switch operation (ASO) in complete transposition of great arteries with ventricular septal defect is usually considered to be within six months. This is because of severe pulmonary arterial hypertension and pulmonary arterial obstructive pathological changes. There are few reports on ASO surgery in children older than three years old.We studied 41 children, including 24 males and 17 females, from January 2010 to December 2011. They were divided into three groups by operation age; 15 patients were1 year old, 13 were 1 - 3 years old, and 13 were3 years old. Associated cardiac abnormalities included patent ductus arteriosus in six cases, atrial septal defect in five cases, and mitral regurgitation in two cases. All the patients had echocardiography before the operation. Seventeen patients underwent a coronary computed tomography examination and five patients underwent right heart catheterization. All ASO surgeries were performed under inhalation anesthesia and hypothermic cardiopulmonary bypass.Three operative deaths occurred. Two were in the1 year old group, who died from severe postoperative low cardiac output. The other was two years old and died of postoperative multiple organ failure. There was no significant difference in postoperative mortality and the recent mid-term survival rate among the three groups. Thirty-eight cases were followed up for an average of 11.2 months, ranging 6 - 20 months. One seven years old patient died of acute diarrhea and electrolyte disturbance arrhythmia caused by food poisoning. Three patients more than three years old still had residual pulmonary arterial hypertension.Children older than three years old can still undergo the ASO procedure, but residual pulmonary hypertension is present.

Congenital heart defects with intractable hypoplasia of the pulmonary arteries without intercourse or with intercourse stenosis is unsuitable for surgical correction or regular palliative procedures. We reported our experience with combined palliative procedures for congenital heart defects with intractable hypoplasia pulmonary arteries.From 2001 to 2012, a total of 41 patients with cyanotic congenital heart defects and intractable hypoplasia of the pulmonary arteries underwent surgical procedures. From among them, 31 patients had pulmonary atresia with ventricular septal defect (VSD) and the other 10 cases had complicated congenital heart defects with pulmonary stenosis. Different kinds of palliative procedures were performed according to the morphology of the right and left pulmonary arteries in every patient. If the pulmonary artery was well developed, a Glenn procedure was performed. A modified Blalock-Taussig shunt or modified Waterston shunt was performed if pulmonary arteries were hypoplastic. If the pulmonary arteries were severely hypoplastic, a Melbourne shunt was performed. Systemic pulmonary artery shunts were performed bilaterally in 25 cases. A systemic-pulmonary shunt was performed on one side and a Glenn procedure was performed contralaterally in 16 cases. Major aortopulmonary collateral arteries were unifocalized in six cases, ligated in two cases and interventionally embolized in two cases. There was one early death because of cardiac arrest and the hospital mortality was 2.4%.Five patients suffered from postoperative low cardiac output syndrome, three had perfusion of the lungs, and two pulmonary infections. Systemic pulmonary shunts were repeated after the original operation in three cases due to the occlusion of conduits. The mean follow-up time was 25 months. The pre- and the post-operation left pulmonary indices were (8.13 ± 3.68) vs. (14.9 ± 6.21) mm(2)/m(2). The pre- and post-operation right pulmonary indices were (12.7 ± 8.13) vs. (17.7 ± 7.78) mm(2)/m(2). The pre- and post-operational pulmonary indices were (20.87 ± 9.43) vs. (32.6 ± 11.7) mm(2)/m(2). They were all significantly increased (P0.001). The diameter of the pulmonary artery increased after the modified Blalock-Taussig shunt ((5.51 ± 0.94) mm(2)/m(2) pre-operation vs. (7.01 ± 1.97) mm(2)/m(2) post-operation), the modified Waterston shunt ((5.70 ± 3.96) mm(2)/m(2) pre-operation vs. (9.17 ± 3.62) mm(2)/m(2) post-operation) and the Melbourne shunt ((2.17 ± 0.41) mm(2)/m(2) pre-operation vs. (7.35 ± 2.49) mm(2)/m(2) post-operation) (all P0.05). Bilateral pulmonary arteries developed well as compared to their pre-operation development. Hemoglobin decreased from (194 ± 27) to (174 ± 24) g/L (P0.05) and peripheral oxygen saturation increased from (65 ± 11)% to (84 ± 6)% (P0.001). During the follow-up of 27 to 49 months, ultimate complete repair was performed in four cases and one patient underwent a Glenn procedure.The procedures should be considered on a case to case basis in patients having hypoplasia of the pulmonary arteries with cyanotic congenital heart defects. Combined palliative operations could be an adequate strategic treatment.

An inflammatory response leading to organ dysfunction and failure continues to be a major problem after injury in many clinical conditions such as sepsis, severe burns, and trauma. It is increasingly recognized that atrial natriuretic peptide (ANP) possesses a broad range of biological activities, including effects on endothelial function and inflammation. A recent study has revealed that ANP exerts anti-inflammatory effects. In this study we tested the effects of human ANP (hANP) on lung injury in a model of oleic acid (OA)-induced acute lung injury (ALI) in rats.Rats were randomly assigned to three groups (n = 6 in each group). Rats in the control group received a 0.9% solution of NaCl (1 ml × kg(-1) × h(-1)) by continuous intravenous infusion, after 30 minutes a 0.9% solution of NaCl (1 ml/kg) was injected intravenously, and then the 0.9% NaCl infusion was restarted. Rats in the ALI group received a 0.9% NaCl solution (1 ml × kg(-1) × h(-1)) intravenous infusion, after 30 minutes OA was injected intravenously (0.1 ml/kg), and then the 0.9% NaCl infusion was restarted. Rats in the hANP-treated ALI group received a hANP (0.1 µg × kg(-1) × min(-1)) infusion, after 30 minutes OA was injected intravenously (0.1 ml/kg), and then the hANP infusion was restarted. The anti-inflammation effects of hANP were evaluated by histological examination and determination of serum cytokine levels.Serum interleukin (IL)-1β, IL-6, IL-10 and tumor necrosis factor (TNF) α were increased in the ALI group at six hours. The levels of all factors were significantly lower in the hANP treated rats (P0.005). Similarly, levels of IL-1β, IL-6, IL-10 and TNF-α were higher in the lung tissue in the ALI group at six hours. hANP treatment significantly reduced the levels of these factors in the lungs (P0.005). Histological examination revealed marked reduction in interstitial congestion, edema, and inflammation.hANP can attenuate inflammation in an OA-induced lung injury in rat model.

Endothelial progenitor cells (EPCs) are used in vascular tissue engineering and clinic therapy. Some investigators get EPCs from the peripheral blood for clinic treatment, but the number of EPCs is seldom enough. We have developed the cultivation and purification of EPCs from the bone marrow of children with congenital heart disease, to provide enough seed cells for a small calibre vascular tissue engineering study.The 0.5-ml of bone marrow was separated from the sternum bone, and 5-ml of peripheral blood was collected from children with congenital heart diseases who had undergone open thoracic surgery. CD34+ and CD34+/VEGFR+ cells in the bone marrow and peripheral blood were quantified by flow cytometry. CD34+/VEGFR+ cells were defined as EPCs. Mononuclear cells in the bone marrow were isolated by Ficoll(®) density gradient centrifugation and cultured by the EndoCult Liquid Medium Kit(™). Colony forming endothelial cells was detected. Immunohistochemistry staining for Dil-ac-LDL and FITC-UEA-1 confirmed the endothelial lineage of these cells.CD34+ and CD34+/VEGFR+ cells in peripheral blood were (0.07 ± 0.05)% and (0.05 ± 0.02)%, respectively. The number of CD34+ and CD34+/VEGFR+ cells in bone marrow were significantly higher than in blood, (4.41 ± 1.47)% and (0.98 ± 0.65)%, respectively (P0.0001). Many colony forming units formed in the culture. These cells also expressed high levels of Dil-ac-LDL and FITC-UEA-1.This is a novel and feasible approach that can cultivate and purify EPCs from the bone marrow of children with congenital heart disease, and provide seed cells for small calibre vascular tissue engineering.

Pediatric patients are susceptible to lung injury. Acute lung injury in children often results in high mortality. Partial liquid ventilation (PLV) has been shown to markedly improve oxygenation and reduce histologic evidence of injury in a number of lung injury models. This study was designed to examine the hypothesis that PLV would attenuate the production of local and systemic tumor necrosis factor (TNF)-α in an immature piglet model of acute lung injury induced by oleic acid (OA).Twelve Chinese immature piglets were induced acute lung injury by OA. The animals were randomly assigned to two groups of six animals, (1) conventional mechanical ventilation (MV) group and (2) PLV with 10 ml/kg FC-77 group.Compared with MV group, the PLV group had better cardiopulmonary variables (P0.05). These variables included heart rate, mean blood pressure, blood pH, partial pressure of arterial oxygen (PaO2), PaO2/inspired O2 fraction (FiO2) and partial pressure of arterial carbon dioxide (PaCO2). PLV reduced TNF-α levels both in plasma and tissue compared with MV group (P0.05).PLV provides protective effects against TNF-α response in OA-induced acute lung injury in immature piglets.

To investigate the influence of coronary artery variation on the outcome of arterial switch operation for transposition of great arteries.Among 280 patients undergoing arterial switch operations at our hospital from 2001 to 2008, 73 (26.1%) had concurrent coronary arteries variation (54 males and 19 females; median age: 0.6 ± 1.1 years old; mean body weight: 5.8 ± 2.6 kg). Of these 73 patients (variant group), 21 cases had transposition of great arteries with a ventricular septal defect and 30 cases with an intact ventricular septum. The other 22 cases were of Taussig-Bing anomalies. Another 207 cases had usual coronary arteries (usual group). Coronary artery transfer was achieved by implantation of buttons to the previously anastomosed neo-aorta.There were 29 early death (10.4%) including 12 cases (16.4%) in variant group and 17 cases (8.21%) in usual group (P0.05). Mean cardiopulmonary bypass and cross-clamp durations were 229 ± 84 and 146 ± 48 min in variant group while 206 ± 59 and 137 ± 40 min in usual group (P0.05). Six cases were confirmed intra-operatively as coronary compression or obstruction. Complications included infection (n = 11), low output syndrome (n = 7), diaphragm paralysis (n = 3), pericardial effusion (n = 2) and atrioventricular block (n = 2).Coronary artery variation increases the operative difficulty and influences the outcome. The operative proficiency may decrease the mortality.

To explore the clinical experiences of combined palliative procedures for cyanotic congenital heart defects with intractable hypoplasia of pulmonary arteries.From August 2001 to September 2009, 31 patients with cyanotic congenital heart defects and intractable hypoplasia of pulmonary arteries underwent surgical procedures. Among them, 26 patients were pulmonary atresia with ventricular septal defect and the other 5 cases complicated congenital heart defects with pulmonary stenosis. Different kinds of palliative procedures were performed according to the morphology of right and left pulmonary arteries in every patient. If the pulmonary artery was well developed, Glenn procedure was performed. Modified Blalock-Taussig or Waterston shunt was performed if pulmonary arteries had hypoplasia. If the pulmonary arteries were of severe hypoplasia, Melbourne shunt was performed. Systemic-pulmonary artery shunts were performed bilaterally in 23 cases. Systemic-pulmonary shunt was performed in one side and Glenn procedure contralaterally in 8 cases.There was one early death because of cardiac arrest. The number of patients suffered from low cardiac output syndrome, perfusion lung and pulmonary infection postoperatively was 5, 3 and 2, respectively. Systemic-pulmonary shunts were reperformed after the original operation in 3 cases because of occlusion of conduits. The mean follow-up time was 25 ± 16 months (6 - 72 months). Left pulmonary index (8.1 ± 3.7 vs 14.9 ± 6.2), right pulmonary index (12.7 ± 8.1 vs 17.7 ± 7.8) and pulmonary index (20.9 ± 9.4 vs 32.6 ± 11.7) increased significantly (all P0.001). The pulmonary diameter increased significantly after modified Blalock-Taussig shunt (5.5 ± 1.0 vs 7.0 ± 2.0), modified Waterston shunt (5.7 ± 4.0 vs 9.2 ± 3.6) and melbourne shunt (2.2 ± 0.4 vs 7.4 ± 2.5) (all P0.05). Bilateral pulmonary arteries developed well compared with that of preoperative condition. Hemoglobin decreased from (194 ± 27) g/L to (174 ± 24) g/L (P0.05) and peripheral oxygen saturation increased from (65 ± 11)% to (84 ± 6)% (P0.001). During the follow-up ultimate complete repair were performed in 3 cases and one patients underwent Glenn procedure.The procedures should be considered for hypoplasia of pulmonary arteries in cyanotic congenital heart defects. Combined palliative operation is an adequate therapy.

Pediatric patients are susceptible to lung injury. Acute lung injury (ALI) in children often results in a high mortality. Partial liquid ventilation (PLV) has been shown to markedly improve oxygenation and reduce histologic evidence of injury in a number of lung injury models. This study aimed to examine the hypothesis that PLV would attenuate the production of local and systemic cytokines in an immature piglet model of ALI induced by oleic acid (OA).Twelve Chinese immature piglets were induced to develop ALI by oleic acid. The animals were randomly assigned to two groups (n = 6): (1) conventional mechanical ventilation (MV) group and (2) PLV with FC-77 (10 ml/kg) group.Compared with MV group, PLV group got better cardiopulmonary variables (P0.05). These variables included heart rate, mean blood pressure, blood pH, partial pressure of arterial oxygen (PaO2), PaO2/FiO2 and partial pressure of arterial carbon dioxide (PaCO2). Partial liquid ventilation reduced IL-1beta, IL-6, IL-10 and TNF-alpha both in plasma and tissue concentrations compared with MV group (P0.05).Partial liquid ventilation provides protective effects against inflammatory responses in the lungs of oleic acid-induced immature piglets.

Advanced pulmonary arterial hypertension is characterized by extensive vascular remodeling that is usually resistant to vasodilator therapy. As the major component of the vascular media, decreased apoptosis of pulmonary arterial smooth muscle cell (PASMC) plays key roles during pulmonary vascular remodeling. Recent studies showed that enhancement of apoptosis of PASMC can reverse pulmonary vascular remodeling and severe pulmonary arterial hypertension. Enhancement of apoptosis of PASMC is becoming a novel strategy to reverse severe pulmonary arterial hypertension. This review analyzes some potential strategies to reverse pulmonary vascular remodeling.

Macrolides antibiotics may affect neutrophil functions that correlate with the inflammation induced by cardiopulmonary bypass. Our study observed the protective effect of clarithromycin on inflammatory lung injury after cardiopulmonary bypass.Twelve adult sheep were randomly divided into two groups. After cardiopulmonary bypass was established, the lung was perfused through the pulmonary artery with either dextran solution (30 mL/kg) in the control group (n = 6) or dextran solution added to clarithromycin (10 mg/kg) in the experimental group (n = 6). Bypass was withdrawn after 90 minutes. Pulmonary function was determined and inflammatory factors were analyzed. Apoptotic neutrophils in the lung were assayed and lung biopsies were also performed.Pulmonary vascular resistance (102.2 +/- 14.0 dyne.s.cm(-5)) was lower in the experimental group compared with the control group (202.6 +/- 47.3 dyne.s.cm(-5), p0.01) whereas the oxygen index was higher in the experimental group (p0.05). Plasma myeloperoxidase in the experimental group (0.015 +/- 0.006 U/L) was lower than that in the control group (0.029 +/- 0.007 U/L, p0.01). Plasma interlukin-8 (0.18 +/- 0.04 ug/L) and tumor necrosis factor (1.00 +/- 0.13 ug/L) in the experimental group were lower than in the control group (0.39 +/- 0.09 ug/L, 1.55 +/- 0.35 ug/L, p0.01). Histologic analyses showed intra-alveolar hemorrhage and neutrophil accumulation in the control group, whereas there were no significant changes in the experimental group. The apoptosis rate of accumulated neutrophils was significantly lower in the control group (p0.01).Lung perfusion with hypothermic protective solution containing clarithromycin distinctly inhibits inflammatory responses caused by cardiopulmonary bypass and ameliorates lung function.