Objective To assess the effectiveness of continuous aspiration of subglottic secretions (CASS)in preventing ventilator-associated pneumonia.Methods The relevant randomized controlled trials were searched in the Cochrane Library,Pubmed,CNKI,VIP and Wanfang databases.The experimental group received CASS and the control group did not(NASS group).Two reviewers selected studies according to the inclusion and exclusion criteria,the quality of studies was critically appraised and data were extracted by two reviewers independently.Meta-analysis was conducted by using RevMan 5.2.Results Sixteen randomized controlled trials met the inclusion criteria and enrolled 2 576 patients.According to the meta analysis,compared with NASS,CASS reduced the incidence of ventilator-associated pneumonia,shortened the length of stay in the intensive care unit and the duration of mechanical ventilation.There was no effect on hospital mortality.Conclusions Continuous aspiration of subglottic secretions appears effective in preventing ventilator-associated pneumonia,decreasing the duration of intensive care unit length of stay and mechanical ventilation among critically ill patients with mechanical ventilation.

Objective To explore the association between maternal methylene tetrahydrofolate reductase (MTHFR) C677T polymorphism and neural tube defects (NTDs). Methods CBM, VIP, CNKI, Wanfang, PubMed and Web of Science databases from set up to March, 2014 were electronically searched to identify case-control studies on the relationship between maternal MTHFR C677T polymorphism and NTDs. The data were quantitatively analyzed by RevMan 5.0 software. Results A total of 25 studies were selected including 2 282 cases and 3 420 controls. Overall, the pooled OR (with 95%CI) under co-dominant model and allele contrast were 2.28(1.60-3.24), 1.25(1.02-1.53) and 1.42(1.21-1.67). Subgroup analysis showed significant association between maternal MTHFR C677T polymorphism and NTDs susceptibility in Asian populations. Conclusion The present meta-analysis suggests that MTHFR C677T polymorphism is significantly associated with maternal risk for NTDs, especially in Asian populations.

Objective To investigate the effects of cold exposure with different time courses on cardiovascular function and skeletal muscle contraction in Sprague-Dawley (SD) rats.Methods The male SD rats were randomly divided into control,12-h cold,24-h cold,and 48-h cold groups.The rats in all cold group were maintained in 4 ℃ environment for indicated time and allowed free access to standard rat chow and water ad libitum.After the animal model was established,the heart,thoracic aorta,soleus,and extensor digitorum longus (EDL) were rapidly isolated from rats under anesthesia and then fixed into the respective organ perfusion system that was connected to physiological recorders and data acquisition system.Lanendorff heart persusion was used to detect some parameters of cardiac function,such as coronary flow (CF),mean left ventricular systolic pressure (mLVSP),mean left ventricular diastolic pressure (mLVDP) and maximum ascending and declining rate of left ventricular pressure (± dp/dt max) ; and then the heart was suffered from 30 min ischemia followed by 60 min reperfusion,the changes of above cardiac function indexes were recorded again.Organ bath method was employed to detect contraction response to potassium chloride (KCl) or phenylephrine (PE) and endothelium-dependent relation responses to acetylcholine (ACh) of aortic rings.The twitch tension,titanic tension,and fatigue test of soleus and EDL were examined by electrical stimulation to reflect contractive function of skeletal muscle.Results The coronary flow (CF) were significantly reduced in 24-h and 48-h cold groups compared to control group [(9.0 ± 1.7) ml/g and (9.8 ± 1.3) ml/g vs (11.6 ± 1.2) ml/g,P ＜ 0.05] ; 48-h cold exposure also showed significantly increased mLVSP (P ＜0.01) and mLVP (P ＜ 0.05) of rats.After ischemia-reperfusion,the heart re-beat time was shorter in all cold exposure groups (all P ＜ 0.01),mLVP and mLVDP were higher in 24-h and 48-h cold group than control group (all P ＜ 0.01).The contraction of aortic rings responses to 60 mmol/L KCl [(0.63 ±0.13) g and (0.79 ±0.11)g vs (1.28±0.17)g,P ＜0.01] and 1 μmol/L PE [(0.62 ±0.18)g and (0.68 ±0.13)g vs (1.25 ± 0.18)g,P ＜ 0.01] were decreased while the endothelium-dependent relaxation responses to low concentration ACh (3 × 10-8 ～ 3 × 10-7) were increased in 24-h and 48-h cold groups relative to control group (all P ＜ 0.05).The 48-h cold also reduced titanic tension of SOL and EDL in comparison with control [(4.14 ± 0.62) N/cm2 vs (5.50 ± 0.75) N/cm2,P ＜ 0.05 and (3.00 ± 0.57) N/ cm2 vs (4.70 ± 0.85) N/cm2,P ＜ 0.01].Conclusions 24 ～ 48 h cold exposure could reduce CF but enhance the tolerance of heart from rats to ischemia reperfusion injury and also decrease the contraction of aortic rings response to KCl or PE but increase the sensitive responses to ACh of aortic rings from rats.The 48-h cold could decrease the contraction of skeletal muscle elicited by electrical stimulation.

Objective To investigate the effects of fasting with different time courses on the contraction of skeletal muscle and cardiovascular function in Sprague-Dawley (SD) rats.Methods The healthy and male SD rats were randomly divided into (1) control,(2) 12 h fasting,(3) 24 h fasting,and (4) 48 h fasting groups.After animal models of fasting with different time courses were established,the heart,thoracic aorta,soleus,and extensor digitorum longus (EDL) were rapidly isolated from rats under anesthesia and then fixed into the respective organ perfusion system that was connected to physiological recorders and data acquisition system.Langendorff heart perfusion was used to detect some parameters of cardiac function,including left ventricular systolic pressure (LVSP),left ventricular end-diastolic pressure (LVEDP),and maximum ascending and declining rate of left ventricular pressure (± dP/dt max).Then,the heart was suffered from 30 min ischemia followed by 60 min reperfusion,the changes in above cardiac function parameters were recorded again.The contraction response to potassium chloride or phenylephrine and endothelium-dependent relation responses to acetylcholine (ACh) of aortic rings were measured with organ bath.The changes of twitch tension and titanic tension of soleus and EDL were examined to reflect contractive function of skeletal muscle.Results The + dP/dt max was significantly reduced in 24 h and 48 h fasting groups compared to the control (P ＜ 0.01).After ischemia-reperfusion,the heart re-beat time was significantly longer [(24.3 ± 7.0)min vs (14.0 ± 2.9)min,P ＜0.05],both mLVDP and mLVP were significantly higher in 48 h and 24 h fasting groups than control group (P ＜ 0.05),and those changes did not normalized until re-perfusion 60 min.The 48 h fasting increased significantly endothelium-dependent relaxation of aortic rings response to low concentration acetylcholine (P ＜ 0.05),but did not affect the maximum relaxation of aortic rings response to high concentration acetylcholine and contraction of aortic rings responses to potassium chloride and phenylephrine.The 48 h fasting also enhanced significantly titanic tension of soleus compared to the control [(7.01 ± 1.22) N/cm2 vs (5.5 ± 0.75) N/cm2 for48 h-Fasting vs Control,P ＜0.05].Conclusions The 24 ～48 h fasting may induce inhibition of cardiac function,while fasting 48 h can increase the sensitivity of aortic rings responses to ACh and contraction function of soleus in healthy and male rats.

Objective To evaluate ‘Cool-tip nee dl e’ radiofrequency ablation (RFA) for the treatment of solid tumors. MethodsIn this study, 102 patients w ith 157 tumors underwent RFA. Tumor size varied from 1.0cm to 20.0cm in d iameter. Result The comple te ablation(CA) rate was 83.5%(91/109)in tumors less than 5cm in diameter , and 35.4%(17/48)when tumors were larger than 5cm. RFA significantl y ameliorates symptoms in most lung cancer patients, and in 40%(4/10)patient s of pancreatic tumors. In the group receiving percutaneous RFA , no patients we re shifted to celiotomy, nor skin burn, or pneumothorax occurred. RFA for hepa tic tumors was complicated with abdominal pain in 13.4%(11/82), nausea in 6 .1%(5/82), jaundice in 9.7%(8/82), fever in 23.2%(19/82), and biliary leak age in 1.2%(1/82). Post RFA complications for pulmonary tumors included pain in 14.3%(1/7)and hypodermal gas accumulation in 14.3%(1/7). For pancrea tic tumors, pancreatic leakage in developed 20%(2/10), elevated blood amylas e in 70%(7/10), GI bleeding in 20%(2/10). Con clusions Treating solid tumors with ‘Cool-tip needle ’ RFA is efficient, reliable and safe, but great care should be taken in case o f pancreatic tumors.

Objective: To observe the effect of coxsackie virus B3 on airway tract and lung morphology, and to study the relation between CVB infection and asthma. Methods: We established CVB3 infective model: 5 d neonatal rats inhaled CVB3 by ultrasonic brume. CVB3-IgM was examined 10 d after inoculating of CVB3, and LW/BW, airway tract and lung pathological change 10 d and 30 d after inoculation of CVB3 were observed. Results: Rats from the virus group had higher D of CVB3-IgM than control's (+2s ) and had higher LW/BW 10 d after inoculation of CVB3 than control (P<0.01). Neonatal rats had acute inflammatory changes 10 d after inoculation of CVB3 and persistent changes in morphology and cytology. Conclusion: Neonatal rats virus model is established. Respiratory infection by CVB3 in neonatal rats has persistent changes in airway tract inflammatory and morphology.

Objective: To observe the effect of coxsackie virus B 3 on airway tract and lung morphology, and to study the relation between CVB infection and asthma. Methods: We established CVB 3 infective model: 5 d neonatal rats inhaled CVB 3 by ultrasonic brume. CVB 3 IgM was examined 10 d after inoculating of CVB 3, and LW/BW, airway tract and lung pathological change 10 d and 30 d after inoculation of CVB 3 were observed. Results: Rats from the virus group had higher D of CVB 3 IgM than control's ( +2s ) and had higher LW/BW 10 d after inoculation of CVB 3 than control ( P

Objective To explore the management strategy for liver trauma combined with juxla-hepatic venous injury and discuss relating factors leading to postoperative deaths. Methods The clini-cal data of 11 patients with juxtahepatic venous injury were retrospectively analyzed in aspects of prefer-ence of irregular hepatectomy and vein repair.There were 8 males and 3 females,at age range of 22-65 years(mean 33.7 years).Injury causes included traffic injury in 7 patients,fall-from-height injury in 3 and crush injury in 1.Of all,9 patients were combined with other abdominal organ injury and 7 with over one part fractures.All patients showed symptom of shock on admission. Results No patient died dur-ing operation but 3 died after operation.The complications included bleeding in 6 patients,severe infec-tion in 2.liver function failure in 3, acute renaI function failure in 2.bile-1eakage in 4,abdominal ab-scess in 4 and incision infection in 6. Conclusion Low blood pressure in the operation is the main cause for death.It is safe and effective to treat liver trauma combined with juxtahepatic venous injury with irregular hepatectomy and vein repair.

Objective:To investigate the molecular epidemiological characteristics of norovirus (NoV) in hospitalized children with sporadic acute gastroenteritis in Tianjin in 2019.Methods:Fecal specimens and clinical data were collected from 3 116 hospitalized children with sporadic acute gastroenteritis possibly caused by viral infection in Tianjin Children′ Hospital between January and December, 2019. Real-time quantitative PCR was used to detect NoV. Partial sequences of RNA-dependent RNA polymerase (RdRp) and capsid genes of NoV were amplified by RT-PCR. Sequence alignment and phylogenetic analysis were performed for further analysis.Results:Among the 3 116 specimens, 809 (26.0%) were positive for NoV. There were significant differences in NoV detection rate between different age groups ( P=0.000), and the highest NoV detection rate (31.6%) was observed in the age group of 7-12 months. Moreover, the detection rate of NoV varied with seasons ( P=0.000), and the NoV detection rate was highest in winter (39.0%). Based on the sequence analysis of RdRp and capsid genes, 286 identified NoV strains belonged to six genotypes, which were GⅡ.P12-GⅡ.3, GⅡ.P16-GⅡ.2, GⅡ.P17-GⅡ.17, GⅡ.Pe-GⅡ.2, GⅡ.Pe-GⅡ.3 and GⅡ.Pe-GⅡ.4. The predominant genotype was GⅡ.Pe-GⅡ.4 Sydney 2012 (61.2%), followed by GⅡ.P12-GⅡ.3 (33.6%, 96/286), GⅡ.Pe-GⅡ.3 (2.4%, 7/286), GⅡ.P16-GⅡ.2 (2.1%, 6/286), GⅡ.Pe-GⅡ.2 (0.3%, 1/286) and GⅡ.P17-GⅡ.17 (0.3%, 1/286). Patients carrying the NoV of GⅡ.Pe-GⅡ.4 Sydney 2012 genotype were likely to suffer from vomiting than those positive for NoV of GⅡ.P12-GⅡ.3 genotype. Conclusions:NoV was an important pathogen causing acute gastroenteritis in children. GⅡ.Pe-GⅡ.4 Sydney 2012 and GⅡ.P12-GⅡ.3 were the major genotypes of NoV in hospitalized children with sporadic acute gastroenteritis in Tianjin in 2019.

Objective:To analyze the epidemiological characteristics and molecular classification of Human adenovirus (HAdV) and Human bocavirus (HBoV) infection in hospitalized children with acute respiratory infection in Tianjin Children′s Hospital.Methods:A total of 1 171 nasopharyngeal aspirates were collected from children with acute respiratory infection in Tianjin Children′s Hospital from March 2019 to February 2020. The specific primers designed by gene sequence were amplified by polymerase chain reation (PCR), and the positive amplification products were determined by sequencing. The sequences of HAdV and HBoV were compared in GenBank, molecular typed and phylogenetic tree analyzed of HAdV by MEGA7.0.26. The positive rate of HAdV and HBoV in different age groups(<6 months, 6-11 months, 12-23 months, 24-35 months, 36-47 months, ≥48 months) and seasons were compared by SPSS20.0.Results:Thirty HAdV were detected in 1 171 specimens, with a positive rate of 2.56% (30/1 171) and 84 cases with HBoV, with a positive rate of 7.17% (84/1 171).The positive detection rates of HAdV and HBoV in different age groups were 1.02% (4/392)-6.61% (8/121) and 4.09% (7/171)-11.45% (26/227), respectively. There was a significant difference in the positive detection rate of HAdV and HBoV in each age group (χ2=12.862, P=0.025; χ2=14.178, P=0.015).Winter is the peak period of HAdV infection, with a positive rate of 5.54% (15/271). The peak of HBoV infection is autumn and winter with a positive rate of 12.00% (36/300) and 12.5% (34/271), respectively, higher than that of the other two seasons (χ2=43.753, P<0.05). There was a significant difference in different season groups (χ2=13.287, P=0.004; χ2=43.753, P<0.05). The sequences of 29 adenoviruses were HAdV-3, 7 serotypes of HAdV-B subgroup and HAdV-1, 2, 5 serotypes of HAdV-C subgroup. Conclusion:HAdV and HBoV play important roles in children′s respiratory tract infections, and are closely related to factors such as the season and the age of the child. They should attract clinical attention.