Objective To simulate the dynamic procedure of bullet damage to the three-dimensional(3D) finite element(FE) model of mandible from different angle with computer-aided engineering.Methods A mandible was scanned by thin-layer CT,and then CT images were analyzed and managed with Dicom standard and Mimics software.At the same time,a simulation of the 3D FE model penetrated by a 7.62-mm bullet was carried out through LS-DYNA software from different angle.Results A 3D FE model of human mandible was established with highly-identical geometric size,and the dynamic process of bullet damage to the model was successfully simulated.The results of this work indicated that the exit wounds in model tended to be larger than the entrances resulting from the same shot.Conclusion Thin-layer CT and Dicom standard can improve the efficiency of establishment of a more precise 3D FE model of mandible.The procedure of bullet damage to the mandible can be simulated by the finite element.

Objective To explore the effects of psoralen(PSO)and long-wave ultraviolet chemical therapy(PUVA) on cell apoptosis and expressions of FasL in HL-60,K562,and NB4 leukemia cells.Methods The cells were taken as the studying objects and their apoptosis ratios,ultrastructure changes and the expressions of FasL were detected in or- der to observe the effects of PSO extracted from Chinese medicine and ultraviolet at 360 nm on human leukemia cells.The factor design and analysis of variance were used to analyze the interaction among the factors.Results(1)PSO,UVA and PUVA all induced the apoptosis and the effects of PUVA were stronger than the other two.(2)Obvious changes of ultra- structure of leukemia cells were found under electron microscope after treatment with PUVA.(3)PSO,UVA and PUVA down-regulated FasL gene and protein expression levels,and the effects of PUVA are the strongest.Conclusion PUVA can induce the apoptosis of human leukemia cells and its effects are the strongest.One of the pathway of PUVA to induce apoptosis is by down-regulating the expression of FasL gene.

Objective To design a wireless monitoring system which can obtain patients' multi-parameters (such as ECG, respiratory, blood pressure, SPO2, and heart rate). Methods The wireless communication system, based on CDMA, receives data through internet and analyses ECG by dealing and measuring signals. Results A wireless monitoring system is designed, which can analyse ECG, blood pressure, and respiratory. Doctors can give diagnostic suggestion based on the monitoring system's analyses and send it to patients by short messages. Conclusion This system can realize long -distance medical monitoring and report the diagnosis to patients timely.

Objective To develop a portable sleep monitoring system with low burden. Methods Information from signals related with sleep were used and dug. Electrodes from patients' body were reduced to decrease patient's physiological and psychological burden. Results Polysomnography(PSG) is the gold standard in detecting the Sleep Apnea Hypopnea Syndrome disease at present. While this method has its problems, such as complicated operation, large expenditure and big physiology and psychology burden for the patient. A sleep monitor system was introduced which has the advantages of convenience, practicality, small physiology and psychology burden for the patient. Conclusion The result indicates that this device is warmly welcomed by doctors and patients, and it is a new device for the diagnosis of the SAHS disease.

AIM: To investigate the survival, migration and differentiation of human bone marrow mesenchymal stem cells (hMSC) in the middle cerebral artery occlusion (MACO) model and to observe the influence on motor function in the animal model. METHODS: hMSC with Hoeschst 33342 were injected into the animal model of MACO after Shenqiye induced for half an hour and their survival, migration, differentiation and the behavior changes in MACO rats were examined. RESULTS: hMSC had good homogeneousness and immunological reaction after implantation. The results showed that hMSC survived in rat brain for a long time over six weeks. As time going, hMSC were found in much more areas in the rat brain. Immunofluorescence staining suggested that implanted hMSC expressed human neuron specific enolase, neurofilament, and glial fibrillary acid protein. At the same time, improvements in abnormal behavior of MACO rats were observed. CONCLUSION: hMSC differentiate into neurons in the brain of rats, which means that hMSC is an ideal seed cells for the therapy of cerebral infarction.

Objective To determine the feasibility of magnetically labeling and tracking mesenchymal stem cells(MSCs)in vitro by using a gadolinium and fluorescent bi-functionally transfection agent of polyethylenimine.Methods A gadolinium bifunctional transfection reagent complex was obtained after the linear polyethylenimine derivative(JetPEI-FluoR)was incubated with Gd-DTPA.Mesenchymal stem cells isolated from the bone marrows of SD rats were cultured and expanded.The mesenchymal stem cells were incubated with the bi-functional labeling agents.After labeling,the MSCs were examined with fluoroscope and electron microscope and the biological characters were detected including trypan blue exclusion test,MTT,and apoptosis detection.On a 1.5 T MR system,the labeled MSCs were examined with spin echo T1 WI and T2 WI and T1 measurement with mixed sequence.After labeling,the cells were cultured and undergone routine passage.Prior MR examinations were repeated for each passage of labeled cells.All data was statistically prolessed with SPSS for Windows.Results Of 5×105 MSCs incubated with the bi-functional agents,4.25×105 MSCs were successfully labeled,the percentage of labeled MSCs was 85% fluoroscopically.The high density electron particles of gadolinium observed electron microscopically existed around cellular apparatuses,especially around Golgi apparatus.In trypan blue exclusion test,the exclusion rate of labeled MSCs with incubation duration of 3,6,12,24 h was(96.55±2.90)%,(94.17±2.56)%,(97.16±3.12)% and(94.23±2.67)%,respectively.The corresponding exclusion rate of unlabeled MSCs was(95.86±2.67)%,(92.04±2.21)%,(93.38±3.64)%and(92.12±2.53)%,respectively.There was no statistical difference of trypan blue exclusion rate between labeled cells and control unlabeled cells within 24 hours of incubation(F=4.523,P＞0.05).In the proliferation test,the optical absorption value of labeled MSC with 2.5,5.0,10.0,20.0,30.0 and 40.0 μl bi-functional labeling agent was(0.1884±0.0151),(0.1878±0.0190),(0.1741±0.0160),(0.1135±0.0215),(0.1079±0.0145)and(0.0811±0.0079),respectively.The corresponding optical absorption value of unlabeled MSCs was(0.1940±0.0116).The optical absorption value of labeled cells was not affected in case of less than 30.0 μl of Gd-DTPA(q'=0.2225-0.9458,P＞0.05).The apoptosis index for labeled cells and unlabeled cells were 5.08% and 3.86%,respectively.On T1 WI,the signal intensity and T1 relaxation time of unlabeled cells and labeled cells were 240.3±24.7 and(2457±56)ms,336.2±20.7 and(1102±64)ms,respectively,and there were significant statistical difference(t=12.656,17.889,P＜0.01).The minimal amount of cells which was detectable for T1 WI was 5×103.After routine passage,the gadolinium in the cells gradually decreased and could be tracked by MRI until the fifth passage.Conclusions The gadolinium and fluorescent bi-functionally labeling rat bone marrow mesenchymal stem cell by using the transfection agent of polyethylenimine is feasible,efficient and safe.The labeled cells could be tracked in vitro on MR imaging.

OBJECTIVETo investigate the effect of shenqi fuzheng injection (SFI) in inducing differentiation of human mesenchymal stem cells (hMSCs) in brain stem and its effect on nervous function in model rats of cerebral infarction.

METHODSMiddle cerebral artery occlusion model rats were made, and hMSCs was injected into their brain after being amplified in vitro and incubated with SFI for 0.5 h, then the survival, migration and differentiation of hMSCs in brain stem as well as the change of nervous function in model rats were observed.

RESULTSThe post-transplantation reject reaction to hMSCs was low, it could survive as long as 6 weeks or more. No difference in area of infarction was shown before and after transplantation. Immunohistochemical staining showed that hMSCs expressed human neuron specific enolase (NSE), neurofilament (NF) and glial fibrillary acid protein (GFAP). The limb-kinetic function and tactile perception were improved in the model rats.

CONCLUSIONSFI can induce hMSCs differentiate into neurons in vivo, and hMSCs may be the ideal germinal cells for treating cerebral infarction.

Animals ; Brain ; metabolism ; Cell Differentiation ; drug effects ; Cell Division ; Cells, Cultured ; Cerebral Infarction ; etiology ; surgery ; Culture Media ; Drugs, Chinese Herbal ; pharmacology ; Humans ; Male ; Mesenchymal Stem Cell Transplantation ; Mesenchymal Stromal Cells ; cytology ; Neurofilament Proteins ; biosynthesis ; Neurons ; cytology ; Phosphopyruvate Hydratase ; biosynthesis ; Rats ; Rats, Sprague-Dawley ; Transplantation, Heterologous

Objective:To monitor the cerebral vascular blood flow parameters in the early stage of simulated acute exposure to high altitude hypoxia by transcranial color Doppler (TCCD), and to evaluate the change trend of cerebral hemodynamics and cerebrovascular reactivity.Methods:Sixty-four healthy volunteers were selected to observe the changes of peak systolic flow velocity(Vs), end diastolic flow velocity(Vd), mean flow velocity(Vm), resistance index (RI) and pulsatility index (PI) of middle cerebral artery (MCA) 30 minutes after they quickly entered the simulated altitude of 4 500 meters. Combined with breath holding test, breath holding index (BHI) was used to evaluate cerebrovascular reactivity (CVR), and subjects were divided into ≤30 years old group and >30 years old group, and the changes of CVR after hypoxia of the two groups were compared.Results:In the early stage of hypoxic environment, compared with baseline, SpO 2 decreased, heart rate increased, and blood flow velocity of middle cerebral artery(Vs, Vd, Vm) increased significantly, BHI showed a decreasing trend (all P<0.01). After hypoxia, the BHI rate of change in >30 years old was lower than that of the subjects ≤30 years old ( P<0.05). After breath holding, cerebral blood flow velocity increased significantly, PI and RI decreased significantly (all P<0.01). Conclusions:Cerebral blood flow is very sensitive to hypoxia. The application of TCCD technology can evaluate the trend of cerebral blood flow dynamics and cerebrovascular reserve capacity in real time and accurately, which is helpful to provide objective basis and research basis for the prevention and treatment of high altitude hypoxia.

Objective:To investigate the clinical efficacy of percutaneous endoscopic lumbar discectomy (PELD) with the aid of neurophysiological monitoring under general anesthesia.Methods:From August 2016 to October 2019, 58 patients underwent PELD under general anesthesia were selected in our hospital; 30 were via transformational approach and 28 were via interlaminar approach. The whole operative procedures were performed under continuous monitoring of spontaneous electromyography (SEMG), and the peak value, waveform and motor unit of SEMG at the surgical side were observed. The clinical outcomes were evaluated by visual analogue scale (VAS) and Oswestry disability index (ODI).Results:PELD was successfully performed in all 58 patients. Abnormal SEMG reactions were recorded in 8 patients (13.8%), manifested as clustered or frequent high amplitude action potentials; 5 patients (16.7%, 5/30) were via transformational approach and 3 (10.7%, 3/28) were via interlaminar approach. Two patients relapsed at 3 and 6 weeks after surgery, respectively; one was treated with PELD again and the other one was treated with lumbar fusion and instrument fixation. The pain at the lumbago and leg was alleviated obviously after surgery in the 56 patients; the VAS scores were 7.43±1.32, 2.55±0.87 and 1.59±0.87 before surgery, and 3 d and 3 months after surgery, respectively, with significant differences ( P<0.05); the mean ODI before surgery and 3 months after surgery were 67.36±7.13 and 12.39±5.48, respectively, with significant difference ( P <0.05). Conclusion:PELD with the aid of neurophysiological monitoring under general anesthesia is safe and reliable, which can achieve good clinical efficacy.