2.Construction of a finite element model for the maxillary first molar and the periodontal tissue
Lin HE ; Haiyan WANG ; Cong XIAO ; Lingling GE ; Xin LI
Chinese Journal of Tissue Engineering Research 2015;19(20):3178-3182
BACKGROUND:Studies have shown that the finite element method could preferably simulate the biomechanical analysis for the object with complicated structures and irregular shapes. The similarities for the finite element model have great influences on the results of the analysis. However, to construct an ideal model is the most time-consuming and complicated portion for the finite element analysis. OBJECTIVE:To construct a finite element model for the maxilary first molar and the periodontal tissue, and to provide a basis of biomechanical researches of the maxilary first molar. METHODS: A volunteer with complete mandibular dentition and healthy periodontal tissue was selected in this study. Cone-beam CT was scanned. The images were saved as DICOM format. These images were imported to the medical modeling software Mimics. The surface model for the maxilary first molar and the alveolar bone was constructed. The model was then imported to GiD for pre-processing. Thus, the complete three-dimensional finite element model for the maxilary first molar and the periodontal tissue was constructed. RESULTS AND CONCLUSION:A finite element model for bilateral maxilary first molar, periodontal ligament and maxilary alveolar bone was constructed, including 896 035 nodes and 4 881 067 elements. This model has restored the geometric shape and the structure of the research object. This study successfuly constructed finite element models of maxilary first molar and the periodontal tissue, which can be a basis of biomechanical researches for the maxilary first molar and the periodontal tissue under the effect of different clinical orthodontic forces.
3.Clinical study on low tidal volume ventilation in the treatment of children with acute hypoxia respiratory failure
Bin LI ; Shufang XIAO ; Lin ZHOU ; Tinghua ZHANG ; Juan HE
Chinese Pediatric Emergency Medicine 2015;22(6):406-409
Objective To explore the efficacy of low tidal volume ventilation strategy in children with acute hypoxia respiratory failure (AHRF).Methods A total of 79 hospitalized children with AHRF from Aug 2006 to Jul 2011 in PICU of Kunming Children's Hospital were enrolled in this study.The observation group in-cluded 55 children who received low tidal volume ventilation strategy (6-8 ml /kg),while the other 24 children (control group)were given traditional mechanical ventilation (10-12 ml /kg).Oxygenation situations such as PaO2 ,PaCO2 ,PaO2 /FiO2 ,oxygen index and blood gas pH value,organ function,mechanical ventilation complica-tions,hospitalization days and expenses in PICU and the mortality were observed.Results (1)PaO2 ,PaO2 /FiO2 and oxygen index in the observation group were better than those in control group after 24 h mechanical ventilation [(68.51 ±7.53)mmHg(1 mmHg =0.133 kPa)vs.(61.64 ±9.28)mmHg,(162.9 ±21.84)mmHg vs.(152.1 ± 19.03)mmHg,and 18.85 ±4.1 vs.26.53 ±5.2,respectively],and there were significant differences between two groups (P ﹤0.05);and there were also significant differences between two groups in the results after 48 h and 72 h mechanical ventilation.(2)The PaCO2 was (47.48 ±10.52)mmHg after 24 h in observation group,while the PaCO2 in control group was (30.17 ±6.59)mmHg,and it suggested excessive ventilation.(3)Mechanical venti-lation time (7.6 ±3.1)d and hospitalization days (12.8 ±3.6)d were shorter in observation group(P ﹤0.01). Barotrauma (7.3%)and mortality (20.0%)in observation group was significantly lower than those in control group (29.2%,41.6%;P ﹤0.01).The number of damaged organs in observation group was lower than that in control group (P ﹤0.05).Conclusion Low tidal volume ventilation with appropriate positive end expiratory pressure could improve oxygenation,prevent alveolar collapse,reduce complications and mortality for children with AHRF,it should be applied for the treatment of children with AHRF.
4.Effects of genistein on neuronal discharges in paraventricular nucleus of rat hypothalamic slices
Ru WANG ; Yuming WU ; Lin XIAO ; Xin WANG ; Ruirong HE
Chinese Journal of Pharmacology and Toxicology 2007;21(4):241-246
AIM To study the central role of genistein (GST) in regulating cardiovascular function of nervous center by examining the effects of GST on the electrical activity of rat paraventricular nucleus neurons in slice preparation and to elucidate the mechanism involved. METHODS Using extracellular single-unit discharge recording technique to examine discharges of neurons in paraventricular nucleus of hypothalamic slices at the resting potential level. RESULTS ①In response to the application of GST 10, 50 and 100 μmol·L-1, respectively, in the perfusate for 2 min, the spontaneous discharge rates (SDR) of neurons in 25/26 hypothalamic slices were significantly decreased in a concentration-dependent manner. ②Pretreatment with L-glutamate 0.2 mmol·L-1 led to a marked increase in the SDR of slices in an epileptiform pattern. GST 50 μmol·L-1 significantly attenuated the increased SDR in all 7 slices. ③In 8/8 slices, the G protein-coupled inwardly rectifying K+ channels (GIRKs) antagonist, tetraethylammonium 1 mmol·L-1 completely blocked the inhibitory effect of GST 50 μmol·L-1. ④Pretreatment with nitric oxide synthase inhibitor Nω-nitro-L-arginine methyl ester 50 μmol·L-1 increased SDR in all 7 slices, but did not affect the inhibitory effect of GST 50 μmol·L-1. CONCLUSION GST can inhibit the electrical activity of paraventricular neurons, and play a protective role on the central neurons. The inhibitory effect of GST may be related to the activation of GIRKs which induce K+ outward current and then engender the cell membrane hyperpolarization, but be not due to the NO release.
5.Effect of high volume hemofiltration combined with mechanical ventilation on seawater respiratory distress syndrome in canine models
Daping XIAO ; Guangming CHEN ; Huakeng LIN ; Jinxuan HE ; Jian CHEN
Chinese Journal of Nephrology 2011;27(10):769-774
ObjectiveTo investigate the effect of high volume hemofiltration (HVHF) combined with mechanical ventilation (MV) on seawater respiratory distress syndrome (SW-RDS) canine models.MethodsTen nomal hybrid dogs were randomly assigned into two groups:MV group(MV group,n=5),all the animals only received MV after establishing model successfully; HVHF combined with MV group (HVHF+MV group,n=5),all were received HVHF plus MV after establishing model successfully.Both groups were observed for 4 hours.Mean arterial pressure (MAP),heart rate (HR),central venous pressure(CVP),arterial blood gas and venous plasma osmotic pressure were detected at baseline,0 min(model establishment),60 min,120 min,180 min,240min after treatment.Venous blood was collected to detect inflammatory mediators (IL-8,IL-6,TNF-α)at baseline,0 min,120 min,240 min after treatment.The lung pathology was examined at the end of the experiment.Results(1)All the animals were suvival after four hous of treatment in both groups. (2)Pattial pressure ofoxygen(PaO2) and O2 saturation(SaO2) rised after four hours of treatment in both groups(P<0.05), and HVHF+MV group was better than MV group.After 4 hours of treatment,pH,actual bicarbonate (AB),bases excess(BE) in HVHF+MV group were significantly better than those in MV group(P<0.05),recovering to the baseline values.(3)MAP,HR,CVP were stable during the four hours of treatment,and compared with 0 min,there was no significant differences after 4 hours of treatment in bothgroups. There were no significant differemces at the same time of treatment in both groups. (4)Plasma osmotic pressure were stable during the four hours of treatment,and compared with 0 min,there was no significant difference in MV group.But in HVHF+MV group,osmotic pressure was significantly higher after 4 hours of treatment than that at the same time in MV group(P<0.05),and compared with 0 min and 180 min,those were higher too(P<0.01). (5)Compared with those at the same time in MV group,plasma inflammatory mediators (IL-8,IL-6,TNF-α) were significantly decreased after 4 hours of treatment in HVHF+MV group(P<0.01).After 4 hours of treatment IL-8,TNF-α in MV group were higher than those at the same time in 0 min (P<0.05).(6)Compared with those in MV group,there were less infiltration of neutrophils,edema and injury of alveolar epithelium from pulmonary pathology.ConclusionsHVHF combined with MV can significantly improve hypoxemia and correct acidosis of SW-RDS model in canines.HVHF can effectively clear plasma inflammatory mediators and redundant water,improve pulmonary pathology changes.HVHF has no impact on MAP,HR and CVP of SW-RDS.
7.Value of Friedman clinical staging systems in management with uvulopalatopharyngoplasty for obstructive sleep apnea hypopnea syndrome.
Pei-Jie HE ; Kuan-Lin XIAO ; Fang-Lu CHI
Chinese Journal of Otorhinolaryngology Head and Neck Surgery 2007;42(2):154-155
Adult
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Humans
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Male
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Middle Aged
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Palatine Tonsil
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pathology
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Sleep Apnea, Obstructive
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pathology
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surgery
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Tongue
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pathology
9.The increasedexpression of PDX-1 may improve insulin resis tance in T2DM rats
Cuijun PANG ; Qiuling CHEN ; Yumei HE ; Lin SONG ; Changqing XIAO
Journal of Chinese Physician 2014;(2):169-172
Objective Pancreatic duodenal homeobox-1 ( PDX-1) plays an important role in the occurrence and development of diabetes.More importantly,its potential application in insulin resistance (IR) improvement is attracting further attention .Berberine has been shown to improve glucose metabolism and insulin resistance .In this study,rat models of type 2 diabetes mellitus ( T2DM) were established by combination of intraperitoneal injection of low -dose streptozotocin and highg-lucose-high-fat diet induction .The effect of berberine on fasting glucose , fasting serum insulin , homeostasis model assessment of insulin resistance ( HOMAI-R) , and ex-pression of PDX -1 of islet in T2DM rats were analyzed .The present study aimed to evaluate the anti-diabetic efficacy of berberine and study the mechanism of its preliminary therapeutic effects .Methods Twenty healthy adult male Sprague Dawley ( SD) rats were di-vided by random number table into the normal control group ( n =6) feeding with a standard diet ,and the experimental group ( n =14 ) given an intraperitoneal injection of streptozotocin .The rats with fasting blood glucose ( FBG) greater than 13.8 mmol/L were ran-domly divided into diabetes mellitus group feeding high sugar high fat diet for two weeks and then continuing with a standard diet , and the berberine group given berberine [180 mg /(kg· d)] every day.The normal control group and diabetes mellitus group were given physiological saline for every day 6 weeks.At the end of 6th week, the rats were executed , and the levels of fasting glucose, fasting se-rum insulin, HOMA-IR, and expression of PDX-1 in pancreas islet of each group were detected .The expression of PDX1-in pancreas islet was examined by immunohistochemistry .The image pro plus 6.0software was used to calculate the integrated optical density ( IOD) of positive expression .Results Compared with the normal control group , FBG, fasting insulin levels ( FINS) , and HOMA-IR of the diabetes mellitus group and berberine group were significantly increased ( P <0.05 ) .Compared with the diabetes mellitus group, FBG, FINS, and HOMA-IR of the berberine group were statistically significantly decreased [ ( 13.11 ±6.87 ) mmol/L vs (18.45 ±4.69) mmol L/, (2.58 ±0.34) μIU/ml vs (2.98 ±0.40) μIU/ml, 1.60 ±0.91 vs 2.75 ±0.28, P <0.05].Compared with the normal control group , the expression of PDX-1 of the islet in the diabetes mellitus group and berberine group was statistically significantly decreased ( P <0.05).After treatment with berberine, FBG, FINS, HOMA-IR, and IOD of PDX-1 in pancreas islet of berberine treatment rats were significantly increased compared with the diabetes mellitus group ( 9.14 ±1.51 vs 6.79 ±0.98 , P <0.01 ) .Conclusions The increases of PDX-1 in islet may be one of the mechanism in the improvement of hyperglycemia .
10.The Arthroscopy Treatment of Intra-articular Osteoid Osteoma: 7 Cases Report
Zhenming HE ; Guoqing CUI ; Gongzhou LIN ; Jian XIAO ; Yuelin HU
Chinese Journal of Sports Medicine 2010;(1):62-64
Objective To summarize the clinical experience of diagnosis and arthroscopic treatment of intratment of intra ular osteoid osteoma.Methods Seven patients(average 22.4 years old with range from 11~32 years)with intra-articular Osteoid osteoma who underwent arthroscopy treatment from March 2006 to June 2009 were studied respectively.Thin-section CT scanning was used to confirm diagnosis and determine surgery location.Results The time span between the appearance of clinical symptoms and confirmed diagnosis was 26.0 months on average(range from 18 to 36 months).At a mean 19-month follow-up,all patients showed significant improvements including VAS decrease,no recurrence,pain relief and normal range of motion.Conclusion The atypical clinical features and radiographic findings of osetoid osteoma might lead to the delayed diagnosis.Using arthroscopy to remove intro-articular osteoid ostema was a safe and effective way.