[A modified mouse model of instable carotid atherosclerotic plaque].

Objective: To explore a modified method for constructing a mouse model of instable carotid plaque and provide the mouse model for simulating the development of human instable carotid plaque. Methods: Twenty-four low density lipoprotein receptor deficiency (LDLr-/-), C57BL/6, male mice were randomized into two groups according to computer-generated table, tandem constriction of carotid artery+ high cholesterol diet (tandem surgery group, n=12); sham surgery+ high cholesterol diet(sham surgery group, n=12). After 12 weeks of consecutive feeding, murine carotid artery were collected and analyzed by carotid ultrasound, pathological examination to assess the formation and stability of atherosclerotic plaque. Results: No statistical difference in body weight and blood lipid level between the two groups was observed (all P>0.05). After surgery, through ultrasound biomicroscopy, obvious stenosis at the two sites of tandem constriction and atherosclerotic plaque between the two sites were observed in tandem surgery group. By pathological examination, no plaque was formed in carotid artery in sham surgery group. The lipid area in the stable plaque of innominate artery in sham surgery group and the plaque of carotid artery in tandem surgery group were (4.8±0.6) ×10(4),(10.2±1.1)×10(4) µm(2), respectively. The difference was statistically significant between the two groups (t=12.023,P<0.001). In addition, the thickness of fibrous cap in the above groups were (122.4±17.8), (41.3±20.2) µm, respectively. The difference was statistically significant either (t=9.224, P<0.001). The region of necrotic core were (3.3±0.4)×10(4),(8.1±0.9)×10(4) µm(2).The difference was statistically significant as well (t=13.456, P<0.001). The percentage of macrophages in innominate artery of sham surgery group and in carotid artery of tandem surgery group were (20.8±5.2)%, (38.6±6.4)%, respectively.The percentage of vascular smooth muscle cells were (32.5±7.3)%,(21.2±5.1)%, respectively (t=6.114,3.585, all P<0.05). The results indicated that the plaque in tandem surgery group had severer inflammatory response. Conclusion: Through tandem constriction surgery upon carotid artery in LDL-/-mouse, instable carotid atherosclerotic plaque can be induced, which is less time-consuming, replicable and effective.

[Multicenter investigation of extracorporeal membrane oxygenation application in pediatric intensive care unit in China].

Objective: To survey the conduction and evaluate the effectiveness of extracorporeal membrane oxygenation (ECMO) therapy in pediatric intensive care unit (PICU) in China mainland. Methods: In a questionnaire-based survey, we retrospectively reviewed the application of ECMO in children's hospital and general hospital in China mainland to summarize and analyze the categories of diseases and prognosis of children treated with ECMO therapy. Results: By December 31, 2017, a total of 23 hospitals using ECMO, including 22 tertiary referral hospitals and 1 secondary hospital, among which 16 were children's hospitals and 7 were general hospitals. Thirty-seven ECMO equipment was available. A total of 518 patients treated with ECMO, within whom 323 (62.4%) successfully weaned from ECMO and 262 (50.6%) survived to discharge. Among 375 pediatric patients, 233 (62.1%) were successfully weaned from ECMO and 186 (49.6%) survived to discharge. Among 143 newborn patients, 90 (62.9%) successfully weaned from ECMO, 76 (53.1%) survived to discharge. ECMO was applied in veno-arterial (VA) mode to 501 (96.7%) patients, veno-venous (VV) mode to 14 (2.7%) patients, and VV-VA conversion mode to 3 (0.6%) patients. Sixty-nine patients required extracorporeal cardiopulmonary resuscitation (ECPR), including 20 newborn patients (29.0%) and 38 pediatric patients (71.0%), who were all with cardiovascular disease. Neonatal respiratory distress syndrome (26/61), persistent pulmonary hypertension of the newborn (PPHN) (12/61), and meconium aspiration syndrome (MAS) (11/61) are the most common pulmonary diseases in newborn patients; among whom, infants with PPHN had highest survival rate (10/12), followed by MAS (9/11). Among newborn patients with cardiovascular diseases, those who admitted were after surgery for congenital cardiac disease were the most common (54/82), while those with septic shock had the highest survival rate (2/3). In pediatric pulmonary diseases, acute respiratory distress syndrome was the most common (42/93), while plastic bronchitis was with the highest survival rate (4/4), followed by viral pneumonia (13/16). Among pediatric cardiovascular diseases, congenital cardiac defect was the most common (124/282), while fulminant myocarditis had the highest survival rate (54/77). Conclusion: The application of ECMO as a rescue therapy for children with severe cardiopulmonary failure has dramatically developed in China mainland.

[Effects and mechanisms of high-volume hemofiltration on endotoxin-induced acute lung injury of piglets].

Objective: To compare the effects of high-volume hemofiltration (HVHF) and continuous veno-venous hemofiltration (CVVH) on cardiopulmonary functions, lung fluid balance, lung damage and cytokine expression in endotoxin-induced acute lung injury piglet model, and to further evaluate the value of high-volume hemofiltration in acute lung injury. Method: Eighteen piglets were randomly divided into the control group (6 piglets), the CVVH group (6 piglets) and the HVHF group (6 piglets). By general anesthesia, the intravenous infusion of 0.15 mg/kg endotoxin were received in all the animals and induced acute lung injury.High-volume hemofiltration and continuous veno-venous hemofiltration were addressed to different groups.Subsequently, hemodynamic parameters (heart rate, mean arterial blood pressure, central venous pressure, pulse contour cardiac index, systemic venous resistance index and extravascular lung water index) as well as gas exchange and lung mechanics parameters (respiratory rate, partial pressure of carbon dioxide, partial pressure of oxygen/fraction of inspired oxygen, dynamic lung compliance and airway resistance) were intermittently measured.Lung tissues were collected for further analysis (the lung wet-to-dry weight ratio, lung injury scoring). The plasma protein levels of cytokines (interleukin(IL) -6, 10 and tumor necrosis factors alpha(TNF-α)) were also assessed.Two-way analysis of variance (ANOVA) and Bonferroni post-test were conducted to identify significant differences among the control, CVVH and HVHF group. Result: Compared with CVVH, HVHF had the capacity to improve significantly the index of Cdyn(HVHF (2.3±0.5) vs. CVVH (1.5±0.5) ml/(cmH(2)O·kg), 1 cmH(2)O=0.098 kPa, P<0.05)and Rrs(HVHF (22.0±1.9) vs.CVVH (29.5±1.5) cmH(2)O/(L·s), P<0.05)at the time of 6 h, and decreased lung water accumulation(index of EVLWI in HVHF (22.7±2.1) vs.CVVH (39.5±2.6) ml/m(2,) P<0.01) at the time of 6 h, and the plasma concentration of cytokines(IL-6, IL-10, TNF-α)in the HVHF group had an obvious decline compared with those in the CVVH group at the time of 6 h( (200±55) vs. (280±61), (74±17) vs. (102±21), (54±13) vs. (73±21) pg/ml, all P<0.05). The lung injury scoring of HVHF group was significantly lower than those of CVVH group((7.8±1.9) vs. (11.3±2.2) scores, P<0.05). Although the plasma concentration of cytokines(IL-6, IL-10, TNF-α) in the CVVH group were lower than those in the control group at the time of 6 h((374±55), (137±25), (98±17) pg/ml, all P<0.05), the indexes of respiratory function were not improved (all P<0.05). Conclusion: Different doses hemofiltration can reduce plasma inflammatory mediators indicators in piglets.Early high volume hemofiltration can improve respiratory function of piglets with endotoxin-induced acute lung injury and reduce lung injury pathological score.

Inhibitory effects of phenolic carboxylic acid analogues on xanthine oxidase.

Nineteen phenolic carboxylic acid analogues were tested for the effects on xanthine oxidase inhibition. 2,2',4,'4'-Tetrahydroxybenzophenone and 2,3,4-trihydroxybenzoic acid displayed the strongest activities (IC50 = 38.70 microM, IC50 = 90.16 microM respectively). Their apparent inhibition constants (Ki) were 7.052 and 0.535 microM respectively, and induced mixed type and competitive type inhibitions respectively with respect to the substrate xanthine.