Right ventricular failure(RVF)is a severe clinical syndrome that affects human health seriously.The establishment and application of experimental animal models are critical to research the pathogenesis, pathophysiology, prevention and treatment of RVF.Recently, numerous researchers have studied the modeling methods and testing indexes of RVF of animal models, which has improved the success rate and quality of the models.However, even if so many models, there is still no widely accepted experimental animal model of RVF because of the different and complex modeling methods, material selection and experimental conditions.This article reviews the methods and mechanism of multiple experimental animal models of RVF and compares them, so as to provide reference for choosing and applying experimental animal models of RVF in the study.

Acute respiratory distress syndrome (ARDS) is a severe respiratory condition that is characterized by rapidly progressive hypoxemia with noncardiogenic pulmonary edema.Despite the improvement of therapeutic methods,the mortality of ARDS is in the range of 40％-50％ all over the world.Some studies have shown that a significant number of patients with ARDS had acute cor pulmonale (ACP),and ACP is independently associated with the mortality of patients with ARDS,which has attracted wide attention in recent years.This paper reviewed recent related studies,summarized the prevalence,pathogenesis and diagnostic approaches of ACP in ARDS,especially echocardiography which was considered as a cornerstone for ACP diagnosis,and elucidated the beneficial effects of right ventricular protective ventilatory strategy and prone-positioning on the pulmonary vasculature and right heart,in order to provide a novel idea for the therapy of ACP in ARDS.

Objective To evaluate the diagnostic accuracy of Streptocuccus pneumoniae urinary antigen test (SpUAT) in patients with community acquired Streptocuccus pneumoniae pneumoniae (SPP). Methods The clinical studies relating SpUAT diagnostic accuracy for community acquired Streptocuccus pneumoniae infection were searched via computer and manual screening of Chinese databases including China National Knowledge Internet (CNKI), China Biology Medicine disc, China Technical Journal Full-text Database, and Wanfang Database as well as English databases such as PubMed, EBSCO, Elsevier Science, Ovid Technologies, and Springer. Data were extracted according to appropriate inclusion and exclusion criteria and analyzed with Meta-disc 1.4 and Stata 12.0 software. Pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio as well as diagnostic odds ratio (DOR) were calculated, and summary receiver operating characteristic curve (SROC) was plotted and area under SROC (AUC) was calculated to analyze the diagnostic accuracy of SpUAT for adult community acquired SPP. Results A total of 15 studies enrolling 6 866 patients were included, all of which with a quality assessment of diagnostic accuracy studies (QUADAS) score not lower than 10, indicating a high study quality. Random effect model was applied owing to non-threshold effect associated heterogeneity. It was shown by Meta analysis that compared with routine pathogen diagnosis (hemoculture, sputum smears, sputum culture and trachea and bronchus attractive culture), the pooled sensitivity, pooled specificity, pooled positive likelihood ratio, and pooled negative likelihood ratio was 73% [95% confidence interval (95%CI) = 71%-76%,] 91% (95%CI = 90%-92%), 6.97 (95%CI = 4.13-11.77), and 0.30 (95%CI = 0.26-0.34), respectively, pooled DOR was 24.34 (95%CI = 13.14-45.11), and AUC of SROC was 0.8051±0.0362. It was indicated by heterogeneity test that experiment design (prospective or retrospective), sample sizes (lower than 200 or higher than or equal to 200), reference test (fewer than 3 or more than or equal to 3 test methods), or literature language (Hispanic or non-Hispanic) had no effect on study heterogeneity, indicating certain other unknown factors may be involved. Funnel plot suggested that 15 involved studies uniformly distributed along the two sides of regression line, indicating no publication bias. Conclusions The use of SpUAT for the diagnosis of adult community acquired SPP has a moderate sensitivity and high specificity. Although the overall accuracy of SpUAT diagnosis is relatively high, there is significant heterogeneity among the studies, so more high-quality studies are needed.

Objective To study the effects of electrical stimulation of efferent vagus nerve on the endotoxic shock in rabbits. Method Sixteen Newzealand rabbits were randomly divided into 2 groups, namely group S as the stimulation group and group C as the control group). Rabbits were subjected to bilateral cervical vagotomy and had challenge with intravenous injection of lipopolysaccharide (LPS) (E. COLI O111: B4 , DIFCO, USA) in a dose of 600 μg/kg. The distal end of the left vagus nerve trunk was connected to an electric stimulator with bipolar electrode and controlled by an acquisition system. Stimuli with stable voltage (10 V,5 Hz,5 ms) were applied twice to the nerve for 10 minutes just before and after the administration of LPS in group S. At the time before and after the infusion of LPS 30 min,60 min, 120 min, 180 min,240 min and 300 min respectively, the heart rate(HR)and the mean arterial blood pressure (MABP) in each animal were recorded, and blood samples were taken for measuring serum tumor necrosis factor-αa(TNF-α) and interleukin-10 (IL-10). Results Compared with group C,the electrical stimulation of efferent vagus nerve could significantly attenuated the LPS-induced hypotension and de-creased the contents of TNF-α[(38.12±7.85) pg/mL vs. (55.12±7.89) pg/mL, P <0.01], but increased the contents of IL-10[(55.12±9.37)pg/mL vs. (40.15±5.44) pg/mL, P <0.01]afar LPS challenge. Conclusions The stimulation of the efferent vagus nerve can down-regulate systemic TNF-α, production and attenu-ate the development of shock after LPS challenge.

AIM: To observe the effects of norepinephrine (NE) on the cardiopulmonary and lung injury in goats with acute respiratory distress syndrome (ARDS) induced by endotoxin. METHODS: A model of septic ARDS was induced by intravenous infusion of low dose endotoxin in six goats. Then 40?10~ -6 NO inhalation was applied to the animals. After 30 min, combined intravenous infusion of NE at concentration of 0.5 mg?kg~ -1 ?min~ -1 was conducted. The dynamic changes in gas exchange and hemodynamics were measured with the aid of Swan-Ganz catheter. Arterial blood gas analysis before and after the onset of ARDS, 30 min after NO inhalation and combined NE was detected. Histology of the lung was also observed. RESULTS: Inhalation of NO rapidly reduced mean pulmonary arterial pressure (MPAP), increased PaO_2, decreased P_ (A-a) O_2 and Qs/Qt in septic ARDS goats. These decrease and increase were more significant than those in NO inhaled alone when animals received NE. The combination of NO inhalation and NE injection resulted in increase in mean arterial pressure. NO inhalation did not ameliorate lung injury and combined NE intravenous injection ameliorated lung injury. CONCLUSION: Injection of low dose norepinephrine improves the beneficial effects of inhaled nitric oxide on lung gas exchange and ameliorates lung injury in goats with acute respiratory distress syndrome induced by endotoxin.

Objective To analyze the risk factors of postoperatively prolonged mechanical ventilation (PMV) after liver transplantation.Method The clinical data of 117 patients who received liver transplantation were retrospectively reviewed.According to the duration of postoperative mechanical ventilation (＜24 h or ≥24 h),the patients were divided into two groups.Commonly-used clinical and lab indexes before,during and after operations were analyzed by using single variance logistic regression analysis,and the screened indexes were analyzed by stepwise multiple variance logistic regression analysis.Result Forty-two patients (35.9％) were diagnosed with PMV after liver transplantation.The intensive care unit stay in the control group was (1.60 ± 1.17) days,shorter than in PMV proup (9.35 ± 10.61days).Sixty indexes were analyzed by univarite logistic regression,and 49 indexes showed statistically significant differences (P ＜ 0.2).Multiple variance logistic regression analysis revealed that the levels of preoperative blood glucose,model for end-stage liver disease score (MELD),the blood loss volume during the operation and the levels of glutamic oxalacetic transaminase within 24 h after the operation showed significant difference.Conclusion Preoperative hyperglycemia,high MELD score,excessive intraoperative blood loss volume and the high level of glutamic oxalacetic transaminase after the operation are independent risk factors of PMV.

Objective:To explore the effect of different tidal volumes (VT) on the hemodynamics of right heart in acute respiratory distress syndrome (ARDS) rats induced by oleic acid (OA).Methods:Sixty adult male Sprague-Dawley (SD) rats were divided into control group ( n = 20), ARDS model group ( n = 20), low VT (LVT) group ( n = 10) and high VT (HVT) group ( n = 10) by random number table. ARDS model was reproduced by injecting OA 0.15 mL/kg through a jugular vein. The control group was given the same amount of normal saline. The success of modeling was judged by the oxygenation index (PaO 2/FiO 2) 2 hours after modeling, at the same time, the lung tissues were collected, the wet/dry weight (W/D) ratio was determined, and the lung histopathological changes were measured by lung injury score. The rats in the LVT group and HVT group were given mechanical ventilation with VT of 6 mL/kg or 20 mL/kg for 4 hours, respectively at 2 hours after modeling. The rats in the control group and the ARDS model group maintained spontaneous breathing. After mechanical ventilation for 4 hours, the heart rate (HR), right ventricular systolic pressure (RVSP), the maximum rate of rising of right ventricular pressure (dp/dt max), and the blood pressure (BP) were measured. Meanwhile, arterial blood samples were collected for blood gas analysis, including pH value, arterial partial pressure of oxygen (PaO 2), arterial partial pressure of carbon dioxide (PaCO 2) and PaO 2/FiO 2. Results:The rats in the ARDS model group showed symptoms of respiratory distress 1 hour after modeling, and the lung tissue samples showed obvious patchy bleeding 2 hours after modeling, while the control group showed no such changes. The PaO 2/FiO 2 in the ARDS model group was significantly lower than that in the control group [mmHg (1 mmHg = 0.133 kPa): 294.3±5.9 vs. 459.0±4.4, P < 0.01], and the lung W/D ratio and lung injury score were significantly higher (lung W/D ratio: 8.24±0.25 vs. 4.48±0.13, lung injury score: 0.60±0.03 vs. 0.12±0.02, both P < 0.01). It indicated that ARDS model was successfully reproduced. The arterial blood gas analysis and hemodynamic parameters of the ARDS model group were significantly worse than those of the control group. After 4-hour mechanical ventilation, the blood gas parameters of the LVT group were better than those of the ARDS model group and the HVT group [pH value: 7.36±0.02 vs. 7.24±0.02, 7.13±0.01; PaO 2 (mmHg): 92.4±2.1 vs. 61.8±2.3, 76.6±2.2; PaCO 2 (mmHg): 49.6±1.7 vs. 61.8±1.8, 33.6±1.3; PaO 2/FiO 2 (mmHg): 440.0±10.2 vs. 274.3±21.4, 364.7±10.5; all P < 0.05]. HR, BP and dp/dt max in the LVT group were significantly higher than those in the ARDS model group and the HVT group [HR (bpm): 346.9±5.4 vs. 302.3±10.1, 265.5±12.2; BP (mmHg): 125.4±2.2 vs. 110.0±2.5, 89.2±2.8; dp/dt max (mmHg/s): 1 393.3±30.3 vs. 1 236.4±20.5, 896.1±19.5; all P < 0.05], and RVSP was significantly lower than that in the ARDS model group and the HVT group (mmHg: 31.3±0.4 vs. 34.0±1.0, 38.8±0.9, both P < 0.05). Conclusion:Mechanical ventilation with low VT can improve the hemodynamic parameters of the right ventricle and protect the function of the right heart in ARDS rats.

Aim To study mRNA and protein expression of eNOS in pulmonary tissue of chronic hypoxic pulmonary hypertension(HPH)rats and chronic hypoxic rats treated with novel KATP opener iptakalim.Methods sixty Sprague-Dawley(SD)male rats were randomly divided into control group, hypoxic group, low dose iptakalim group(0.75 mg·kg~(-1)·d~(-1)), and high dose iptakalim group(1.5 mg·kg~(-1)·d~(-1)).Except the first group, the other three groups were put into hypoxic and normobaric chamber (10%±0.5% O_2,8 h/day and 6 day/week) to establish chronic hypoxic model. After four weeks, the mean pulmonary arterial pressure(mPAP), RV/(LV+S)and the plasma concentration of NO were measured. RT-PCR was performed to analyze the mRNA expression of eNOS in pulmonary tissue. Western blot was performed to analyze the protein expression of eNOS, iNOS in pulmonary tissue. Results ① The level of mPAP and RV/ ( LV + S) were significantly higher in the hypoxic group than those in control group ( P < 0. 05 ) , Low dose iptakalim groupandhighdoseiptakalimgroupdecreased the level of mPAP and RV/( LV + S) significantly (P <0. 05). ② The level of NO was significantly lower in the hypoxic group than those in control group (P<0. 05). Low dose iptakalim group and high dose iptakalim group increased the level of NO significantly (P < 0. 05 ). ③ The mRNA and protein expression of eNOS in the hypoxic group were significantly lower than those in the control group (P < 0. 05 ). Low dose iptakalim group and high dose iptakalim group increased the expression of eNOS significantly ( P < 0. 05). High dose iptakalim group was more significant. Conclusion Pulmonary vascular endothelial dysfunction is induced by chronic hypoxia,and the level of NO, the mRNA and protein expression of eNOS are decreased. Iptakalim can improve the vascular endothelial dysfunction, increase the expression of eNOS and the level of NO and reverse hypoxic pulmonary hypertension.

Despite the great improvements in the techniques and perioperative management of liver transplantation in recent years, there are still several perioperative complications that may lead to the poor prognosis of recipients. Prolonged mechanical ventilation (PMV) is a common complication in the early stage after surgery and may result in a high incidence rate of postoperative complications, prolonged length of stay in the intensive care unit and hospital stay, and an increase in mortality rate. In recent years, many studies have reported PMV after liver transplantation, but no summarization and statistical analysis have been performed and there are still no effective measures to prevent PMV after liver transplantation. This article summarizes the influencing factors and interventions for PMV after liver transplantation, in order to provide valuable information for reducing the duration of mechanical ventilation after liver transplantation and improving the prognosis of liver transplantation recipients.

Objective To investigate the effect of pre-transplant metabolic syndrome (MS) on new-onset postoperative atrial fibrillation (POAF) in adult liver transplant recipients.Methods Adult patients (age ≥18 years) who underwent primary liver transplantation at the UCLA Medical Center between January 2009 and December 2015 were retrospectively reviewed.Clinical data were collected after obtaining institutional review board approval.MS was defined according to the 2009 harmonized definition.POAF was defined as new-onset atrial fibrillation within 30 days after liver transplantation in patients without chronic persistent atrial fibrillation.Patients were divided into two groups:MS and non-MS groups.Incidence of POAF was compared between two groups.Then,univariate and multivariate logistic regression analyses were performed to assess the relationships between MS and POAF.Results Of 842 patients,prevalence of pre-transplant MS was 29.4％.POAF occurred in 71 patients (8.4％).The incidence of POAF between MS and non-MS groups significantly differed (14.6％ vs.5.9％,P＜0.01).The logistic regression analysis revealed that the presence of MS was significantly associated with POAF [odd ratios (OR) 2.290,95％ CI 1.342-3.907].Other risk factors include recipient age,prior history of AF,and preoperative baseline creatinine (OR 1.030,2.479 and 1.380,respectively,all P＜0.05).Conclusion The presence of pre-transplant MS is an independent risk factor for POAF in liver transplantation patients.Pre-transplant MS should be properly diagnosed and managed before transplantation.