History, 20th Century ; History, 21st Century ; Periodontics ; history

ObjectiveTo investigate the effect of tranexamic acid on inflammatory response in patients undergoing off-pump coronary artery bypass grafting (OPCABG).Methods Sixty ASA Ⅰ -Ⅲ and NYHA Ⅰ -Ⅲ patients of both sexes,aged 45-64 yr,with body mass index 16-22 kg/m2,undergoing elective OPCABG,were randomly divided into 2 groups ( n =30 each):control group (group C) and tranexamic acid group (group T).Anesthesia was induced with iv injection of midazolam,fentanyl and pipecuronium.The patients were tracheal intubated and mechanically ventilated.PETCO2 was maintained at 35-45 mm Hg.Tranexamic acid 1 g was infused intravenously over 30 min after induction followed by continuous infusion at 400 mg/h until the end of operation in group T.While equal volume of normal saline was given in gtoup C.Anesthesia was maintained with inhalation of isoflurane and intermittent (i)v boluses of fentanyl and pipecuroninm.Venous blood samples were taken before induction,at the end of operation and 24 h after operation for determination of Hb,platelet count,prothrombin time,international normalized ratio and plasma D-dimer and IL-6 concentrations.The volume of chest tube drainage was collected and recorded at 6 and 24 h after operation.The requirement for transfusion of allogeneic red blood cells and fresh frozen plasma was recorded.The complications during hospital stay were also recorded.ResultsCompared with group C,the plasma concentrations of D-dimer and IL-6 were significantly decreased at the end of operation and 24 h after operation,and the volume of chest tube drainage and the requirement for transfusion of allogeneic red blood cells and fresh frozen plasma were significantly decreased after operation in group T ( P ＜ 0.05 or 0.01).There was no significant difference in Hb,platelet count,prothrombin time and international normalized ratio between the two groups (P ＞ 0.05).No complications occurred during hospital stay in the two groups.ConclusionTranexamic acid can reduce inflammatory response in patients undergoing OPCABG.

Objective To observe the dynamic change of cerebral blood flow of newborns with hypoxic-ischemic encephalopathy(HIE).Methods Cerebral blood flow of middle cerebral artery and pulsatility index(PI) on 75 newborns with HIE and 50 normal infants were examined with transcranial doppler sonography at different time points,and the relations between cerebral blood flow and clinic indexes were analyzed.Results The blood velocity of normal infants increased gradually, and PI decreased from 2 to 5 days.The velocities were lower than that of normal infants,and PI was higher at 12th hour and 1st day, but during 2-5 days,the velocities got higher and PI got lower, in which the decrease of velocities correlated positively with Apgar scores and the increase of velocities were negatively correlative to Apgar scores.Compared with the neonates who had poor prognosis retrospectively with those had good prognosis, the velocity changes were found to be more significant.Conclusion The change of cerebral blood flow can show the pathophysiology of HIE and prognosticate the prognosis of neonates with HIE.

Objective To design a hemostatic clip and evaluate its efficacy and success rate of closure of stomach wall defect after full thickness resection (FTR).Methods A full thickness circular or linear resection (3 to 5 cm) was made on each model's antrum with needle knife and insulated-tip knife.The specimens were divided into 2 groups, using either an interrupted or continuous suturing method.Then the closure condition, suturing time, number of clips required and success rate of closure were compared.Results All 12 defects were successfully closed.The average closing time of interrupted and continuous suturing group were 13.33 ± 1.09 and 10.17 ±2.11 minutes, and the mean number of clips used were 4.67 ± 0.82 and 2.67 ± 0.82.The success rate was 100％.Conclusion This newly designed clip is a fast, reliable and convenient tool for stomach wall defect closure after FTR.

Objective:To investigate the effect of Na + , K + -ATPase on the increase of cytosolic Ca 2+ level induced by hypoxia in rat cortical neurons. Methods: Using confocal laser scanning microscope and video based motion edge detection system, we measured the intracellular Ca 2+ concentration (\ i ) and Na + concentration (\ i ) in cortical neurons exposed to hypoxia for different time periods and at presence of different concentrations of dihydroouabain (DHO, an inhibitor of Na + , K + -ATPase). We also observed the effect of Na + , K + -ATPase on the increase of cytosolic Ca 2+ level induced by hypoxia in rat cortical neurons. Results: DHO (10 -9 -10 -3 mol/L) dose-dependently and hypoxia(4-20 min) time-dependently increased the levels of \ i and \ i in cultured cortical neurons. \ i and \ i increased significantly 4 min after cortical neurons were exposed to hypoxia, and addition of DHO (10 -3 mol/L) further increased their concentrations. While 15 min after hypoxia exposure, different concentrations of DHO did not further increase \ i and \ i. We also found that hypoxia exposure did not enhance DHO pretreatment-induced \ i increase. Conclusion: Inhibition of Na + , K + -ATPase activity is one of the mechanisms responsible for hypoxia-induced elevation of \ i in cortical neurons.

Objective To reproduce a scratch-wound model in cultured rat astrocytes (AST).Methods The secondary cultured AST prepared from newborn Wistar rat cerebral cortex were scratched with plastic pipette tips. The morphologic change of AST was observed through microscope at 10 min before and 1, 3, 6, 12, and 24 h after injury, meanwhile the lactate dehydrogenase (LDH) leakages in the cultured medium were determined.Results Immediately after injury the edge of the scratch was lined with irregularly shaped cell. 6 h after injury the AST processes began extending to cell-free area, and elongated further at 12 and 24 h after injury, with presented of new generated cells in the denuded area. At different times after injury, the LDH leakages of the experiment group were higher than that before injury ( P<0.05), and were higher than that of the control group ( P<0.05).Conclusion According to observed AST morphologic changes and determined LDH leakages in culture medium, the scratch-wound model in cultured rat AST is successfully reproduced.

Objective To investigate the protective effect of methylene blue (MB) on blood-brain barrier (BBB) injury after focal cere-bral ischemia-reperfusion in rats. Methods 18 male Sprague-Dawley rats were randomly divided into sham-operated group (n=6), model group (n=6) and MB treatment group (n=6). The left middle cerebral arteries were occluded for 1 hour and reperfused. MB was infused intra-venously immediately after reperfusion (3 mg/kg) and again 2 hours post-reperfusion (1.5 mg/kg), while normal saline was administered in the model group. The sham-operated group was treated as same as the model group without occlusion and infusion. HE staining was used to observe the histological injury in the cortex around the infarcted region 47 hours after reperfusion, while albumin immunohistochemistry was used to evaluate the permeability of the BBB, and immunohistochemistry and double immunofluorescence staining were used to exam-ine the expressions of glial fibrillary acidic protein (GFAP) and aquaporin-4 (AQP-4). Results HE staining showed that cells and blood ves-sels were not intact in the cortex around the infarcted region in the model group and they were better in the MB treatment group. The expres-sions of the albumin, GFAP and AQP-4 were higher in the model group than in the sham-operated group (P<0.01), and were lower in MB treatment group than in the model group (P<0.05). The double immunofluorescence staining showed the colocalization of GFAP and AQP-4 in the astrocytes. Conclusion MB may ameliorate the BBB disruption induced by focal cerebral ischemia-reperfusion through reducing glio-cyte proliferation and down-regulation of AQP-4 expression in rats.

Objective To synthesize antimicrobial bioceramic using chitosan and calcium phosphate cements mixed with ceftriaxone sodium. Methods The bioceramic was synthesized through the hardening of chitosan liquid combined with calcium phosphate cements and cefiriaxone sodium.The released ceftriaxone sodium was studied according to the linear equation between UV-VIS absorbance to concentration.The in vitro bactefiostatic effect of the chosen bioceramic was investigated via the microbiological method.The model of rats'contaminated bone defect were deployed to study the antimicrobial performance of the bioceramic. Results The best synthesis condition was chosen at:0.1g calcium phosphate cements and 10.4 mg ceftriaxone sodium combined with 2.4 ml hardening liquid C.then keeping the mixture at 60℃ and 100%humidity for 24 h.In vitro release of the resulting antimicrobial bioceramic remained stable,while that of ceftriaxone sodium lasted for a week,higher than the minimal inhibitory concentration(MIC) of Staphylococcus aureus.As proved by the WBC number and tissue sectioning,a lighter inflammatory response of treatment group was observed as compared with the control group. Conclusion The antimicrobial bioceramic combined with chitosan and ceftriaxone sodium shows promising antimicrobial performance.

Psychrotrophs were isolated by using four media from low-temperature sewage of sewage treatment plant in Urumqi, Xinjiang. Totally, 154 strains were obtained including 12 filamentous fungi, 46 yeasts, 6 actinomycetes and 90 bacteria. The results of tolerance tests of the isolates to salt, phenol and SDS, and enzyme producing characters of amylase, proteinase and esterase were shown. Then 60 bacterial strains were chosen for 16S rRNA gene sequencing and analysis. The blasting results showed that the strains were assigned to 13 recognized genera , and the Strain 39 exhibited 96.6% similarity to Acinetobacter lwoffii(DSM2403), indicating that it might be a novel species. These results suggested that there were a lot of psychrotrophs and rich bacterial diversity in low-temperature sewage. In addition, which maybe an important and potential library of microbial resources.