RIP1-dependent linear and nonlinear recruitments of caspase-8 and RIP3 respectively to necrosome specify distinct cell death outcomes

There remains a significant gap in our quantitative understanding of crosstalk between apoptosis and necroptosis pathways. By employing the SWATH-MS technique, we quantified absolute amounts of up to thousands of proteins in dynamic assembling/de-assembling of TNF signaling complexes. Combining SWATH-MS-based network modeling and experimental validation, we found that when RIP1 level is below ~1000 molecules/cell (mpc), the cell solely undergoes TRADD-dependent apoptosis. When RIP1 is above ~1000 mpc, pro-caspase-8 and RIP3 are recruited to necrosome respectively with linear and nonlinear dependence on RIP1 amount, which well explains the co-occurrence of apoptosis and necroptosis and the paradoxical observations that RIP1 is required for necroptosis but its increase down-regulates necroptosis. Higher amount of RIP1 (>~46,000 mpc) suppresses apoptosis, leading to necroptosis alone. The relation between RIP1 level and occurrence of necroptosis or total cell death is biphasic. Our study provides a resource for encoding the complexity of TNF signaling and a quantitative picture how distinct dynamic interplay among proteins function as basis sets in signaling complexes, enabling RIP1 to play diverse roles in governing cell fate decisions.

Analysis on injuries of drivers and passengers in motorcycle traffic accidents in Chongqing area / 重庆医学

Objective To investigate the characteristics of personal injuries in motorcycle accidents in Chongqing area to provide the reliable information and reference basis for reducing the injury and death risk of the motorcycle accidents.Methods Two hundreds and thirteen cases of motorcycle traffic accident occurred in Chongqing area from January 2015 to June 2016 were deeply collected,the collected contents included the basicinformation,driver information and personal injury,etc.Then accident data were statistically analyzed.Results The death rate of motorcycle drivers was higher than that of the pillion passengers.The death causes of craniocerebral injuries and craniocerebral injuries complicating thoracic and abdominal organ injuries accounted for 58.8％ and 20 ％ respectively,the proportions of head and neck,chest and back,lower extremity,upper extremity,abdominal and pelvic part and perineal part MAIS ≥2 were 71％,59％,33％,25％,20％ and 7％ respectively.The perineal injury rate of motorcycle drivers was higher than that of the pillion passengers.The ratio of occurrence rates between lower extremity fracture to upper extremity fracture was 1.8 ∶ 1,the persons in motorcycles-trucks accidents were easier to suffer from vehicle crushing.Conclusion Head and chest injuries are important causes leading to motorcycle drivers and pillion passengers' death and injury.The perineal injury can serve as an important basis for identifying the drivers and pillion passengers in partial motorcycle accidents.

Biomechanical behavior of brain injury caused by sticks using finite element model and Hybrid-III testing / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To study the biomechanical mechanism of head injuries beaten with sticks, which is common in the battery or assaultive cases.</p><p><b>METHODS</b>In this study, the Hybrid-III anthropomorphic test device and finite element model (FEM) of the total human model for safety (THUMS) head were used to determine the biomechanical response of head while being beaten with different sticks. Total eight Hybrid-III tests and four finite element simulations were conducted. The contact force, resultant acceleration of head center of gravity, intracranial pressure and von Mises stress were calculated to determine the different biomechanical behavior of head with beaten by different sticks.</p><p><b>RESULTS</b>In Hybrid-III tests, the stick in each group demonstrated the similar kinematic behavior under the same loading condition. The peak values of the resultant acceleration for thick iron stick group, thin iron stick group, thick wooden stick group and thin wooden stick group were 203.4 g, 221.1 g, 170.5 g and 122.2 g respectively. In finite element simulations, positive intracranial pressure was initially observed in the frontal comparing with negative intracranial pressure in the contra-coup site. Subsequently the intracranial pressure in the coup site was decreasing toward negative value while the contra-coup intracranial pressure increasing toward positive values.</p><p><b>CONCLUSIONS</b>The results illustrated that the stiffer and larger the stick was, the higher the von Mises stress, contact force and intracranial pressure were. We believed that the results in the Hybrid-III tests and THUMS head simulations for brain injury beaten with sticks could be reliable and useful for better understanding the injury mechanism.</p>

Study on pedestrian thorax injury in vehicle-to-pedestrian collisions using finite element analysis / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To explore the relationship between the collision parameters of vehicle and the pedestrian thorax injury by establishing the chest simulation models in car-pedestrian collision at different velocities and angles.</p><p><b>METHODS</b>87 cases of vehicle-to-pedestrian accidents, with detailed injury information and determined vehicle impact parameters, were included. The severity of injury was scaled in line with the Abbreviated Injury Scale (AIS). The chest biomechanical response parameters and change characteristics were obtained by using Hyperworks and LS-DYNA computing. Simulation analysis was applied to compare the characteristics of injuries.</p><p><b>RESULTS</b>When impact velocities at 25, 40 and 55 km/h, respectively, 1) the maximum values of thorax velocity criterion (VC) were for 0.29, 0.83 and 2.58 m/s; and at the same collision velocity, the thorax VC from the impact on pedestrian's front was successively greater than on his back and on his side; 2) the maximum values of peak stress on ribs were 154, 177 and 209 MPa; and at the same velocity, peak stress values on ribs from the impact on pedestrian's side were greater than on his front and his back.</p><p><b>CONCLUSION</b>There is a positive correlation between the severity and risk of thorax injury and the collision velocity and angle of car-thorax crashes. At the same velocity, it is of greater damage risk when the soft tissue of thorax under a front impact; and there is also a greater risk of ribs fracture under a side impact of the thorax. This result is of vital significance for diagnosis and protection of thorax collision injuries.</p>

Investigation of characters on functions and pathology of primary brainstem injury in rabbits / 重庆医学

Objective To study characters of pathology associated with functional alteration of primary brainstem injury (PBI) at different injury severities in rabbits .Methods Animal model of graded PBI was produced using rabbits .Animals were di‐vided into five groups ,group Ⅰ to Ⅳ with an increase of impact power ,10 cases in each group ,and the control group with 5 cases . The pathology characters of PBI were investigated combining dissection observation with unaided eye ,tissue HE histochemical stai‐ning and electron microscope .Results Slight brainstem injury were observed in group Ⅰ ,and pathological results showed regional subarachnoid hemorrhage (SAH) ,stripping of regional cerebral pia mater ,a few petechial hemorrhage in surface ,nerve cell edema , normal medulla sheath and axon roughly .The brainstem injuries were apparent in group Ⅱ ,and the pathological changes indicated SAH in sheet ,petechial and sheeted hemorrhage in surface ,and slight swelling and vacuoles in nerve cells .The brainstem injuries were observed obviously in group Ⅲ ,exhibiting thick SAH ,petechial and sheeted hemorrhage in surface and inside ,degeneration of nerve cells ,abruption of axon ,and atrophy of axoplasm .Eight of ten animals died of respiratory depression induced by brainstem in‐jury in group Ⅳ ,presenting thick hemorrhage in subarachnoid surrounding brainstem ,the whole brainstem injured ,microscopically with multiple small hemorrhage ,nerve cells only residual nuclei ,myelin lamellar severe stratification and fracture ,and axonal tran‐section ,disintegration .No abnormal pathological changes were shown in control group .Conclusion The impacts to brainstem with higher powers lead to more manifest functional and more severe pathological changes ,with an alternation of injury location from surface to deep .

Early diffusion tensor imaging findings in animal models of acute diffuse axonal injury / 中华创伤杂志

Objective To establish animal models of diffuse axonal injury (DAI) and discuss the early functional MRI findings.Methods Twenty-five adult white rabbits were divided into control group (n =5),mild DAI group and severe DAI group (n =6) according to random number.Mild DAI group was subdivided into mild DAI 3 h (n =6),1 day (n =4) and 1 week (n =4) groups.Routine MRI and diffusion tensor imaging (DTI) were performed.Parameters measured were fractional anisotropy (FA),apparent diffusion coefficient (ADC),axial diffusivity (AD) and radical diffusivity (RD).Results Significantly increased FA (P＜0.01) and decreased ADC (P＜0.05) and RD (P＜0.01) were detected in severe DAI group compared to control group,but there was no significant variation in AD between the two groups (P ＞ 0.05).Each parameter remained almost unchanged in mild DAI 3 h group and mild DAI 1 week group,but FA was increased (P ＜ 0.01) and RD decreased (P ＜ 0.05) in mild DAI 1 day group,with no changes of ADC and AD.Conclusion DTI is a sensitive way to detect the occurrence and development of DAI and can provide referential images for early DAI diagnosis.

Study on the resonance frequency comparison between rat and rabbit bowels / 国际生物医学工程杂志

Objective To find out the accurate resonance frequencies and vibration characteristics of intestine,lung,kidney,stomach,heart and liver of rat and rabbit in low frequency and to provide basic data for the study of organs' resonance injury and reaction.Methods Eight rats and eight rabbits were anaesthetized with 1.5％ sodium pentobarbital and acceleration sensor was fixed to the surface of their bowels.The rats were fastened on their back on the veneer hung horizontally by rubber band.The veneer was hammered upward from the down side,and the biggest value of frequency spectrum was considered the resonance frequency.Rabbits were fastened on their back on vibration platform and 2 mm amplitude vibration was given with the sweeping-frequency from 2 Hz to 50 Hz.The bowels amplitudes on each frequency point were measured.The frequency corresponding to the biggest amplitude was considered the resonance frequency.Results The resonance frequencies of rat intestine,lung,kidney,stomach,heart and liver were respectively 3.8,3.2,6.6,7.0,4,6 and 3.0 Hz within frequency interval of 0 Hz to 20 Hz.The resonance frequencies of rabbit intestine,lung,kidney,stomach,heart and liver were respectively 6.0,5.0,7.0,8.0,6.0 and 7.0 Hz within frequency interval of 2 Hz to 50 Hz.The vibration amplitude of lung was the biggest at the resonance frequency.The resonance frequencies of both rat and rabbit bowels showed no statistical correlations to body weights,bowel mass and bowel volumes.Conclusion Bowel resonance frequencies of rat and that of rabbit are evidently statistical different except for that of kidney.The resonance frequency values of rabbit bowels are closer to that of dog and monkey than to that of rat.Thus the resonance injury characteristic of rabbit bowels can be the research basis for dog,monkey,and even human bowels resonance injury.

Development of the first head finite element model based on Chinese visible human data / 生物医学工程学杂志

The second Chinese visible human (CVH) data has been used to build a more precise finite element model of Chinese head via 3-D image reconstruction, solid model reconstruction, finite element meshing, and assembling of finite element model. This second case of finite element model of Chinese head contains skull, facial bones, inferior maxilla, cerebral falx, brain, cerebellum brainstem, and so on. All the mesh elements, according to their main quality check results in line with the engineering requirements, were identified as solid elements, and the numbers of nodes and elements were determined to be 31 223 and 19 911 respectively. The model is coincident with the anatomy of human head; and its accuracy in some region, especially in fundus cranii and fundus cranii, is more excellent than that of the other models based on CT/MRL The development of the first head finite element model based on CVH data has brought on a remarkable progress in the application of CVH platform.

Effect of splenectomy on mortality and brain water content of rats with brain injury / 中华创伤杂志

Objective To observe the effect of splenectomy on mortality and brain water content of rats with brain injury so as to explore novel way for better clinical management of patients with severe traumatic brain injury. Methods Adult male SD rats were randomly divided into three groups, ie, sham operation on brain and spleen (Group A, n = 23), experimental brain trauma & sham operation on spleen (Group B, n =48) and experimental brain injury & splenectomy (Group C, n = 47). Modified Feeney' s method was used to create the animal model of experimental brain trauma, Longa' s scale was applied to evaluate the neurologic defect. Mortality within seven days following brain injury was calculat-ed. In the meantime, the brain water content was detected at days 1 (n = 8), 2 (n = 8), 3 (n = 8) and 7 (n = 7) after brain injury in each group, Results No statistical difference of Longs' s scale was found between Group B and Group C (P > 0.05). The mortalities within seven days after brain injury were 0%, 35.42 and 14.89% in Groups A, B and C respectively, with statistical difference between groups (P<0.05). The brain water content of Groups B and C at days 1, 2, 3 and 7 were (81.98±0.35)% & (81.78±0.41)%, (82.58±0.63)% & (81.81±0.48)% (P<0.05),(82.54±0.54)% & (81.52±0.84)% (P<0.05) and (81.50±0.41)% & (81.21±0.36)% (P>0.05) respectively. Conclusion Splenectomy can effectively reduce brain water content and significantly decrease mortality in rata with brain injury.

Preliminary application of 64-slice multislice computed tomography in postmortem after a road traffic accident / 中华创伤杂志

Objective To investigate the value of 64-slice multislice computed tomography (MSCT)in full-body postmortem examination after a road traffic accident.Methods The process of road traffic accident involving a pedestrian was obtained from scene monitoring photographic recordings and scene investigation photos.First,the external autopsy was performed by professional forensic pathologist who then reported the autopsy results.Then,64-slice MSCT was employed to perform a full-body scanning,when the CT sectional images were processed with muhiplanar and 3D reconstructions.The CT imaging results were then compared with the autopsy findings to find difference.Results The external autopsy found many soft tissue injuries over the body,subarachnoid hemorrhage,haematothorax,multiple rib fractures and nasal bone fractures and viewed that craniocerebral injury and thoracic injury caused the death after road traffic accident.While 64-slice MSCT revealed severe injuries in many organs including head,chest,abdomen,pelvis and spine.Conclusions Compared with the external autopsy,64-slice MSCT can obtain more important information of tissue and organ injuries.Combined use of 64-slice MSCT and external autopsy can provide sufficient and reliable proofs for identification of road traffic accident injuries.

The Modeling Study of the Cavitation Effect in Brain Tissue during the Brain Deceleration Impact / 中国医学物理学杂志

Purpose: Set up a new technique to reproduce the cavitation effect in the process of brain deceleration impact Methods: A transparent physical brain model with tiny air bubbles was built and loaded on an upright brain deceleration impacting moveable platform. Then, in the high strength lighting circumstance, the moveable platform was made to free fall from a height of 40cm and impacted on a fixed platform, and the whole deceleration impacting process was recorded by a high-speed video camera. Using the serial pictures analysing software, the volume and mean pressure change of the air bubbles were calculated and the cavitation effect of the brain tissue during the impact was studied. Results: The volume of the air bubble in the contrecoup site increased obviously in the impacting process, the volume of the air bubble in the coup site decreased in the impacting process and the volume change of the air bubble in the middle site was not evident enough in the impacting process. Conclusion: The results proved the negative pressure and the cavitation phenomenon in the contrecoup site. The experiments explicitly and directly showed the cavitation effect in the contrecoup site during the decelerating impact It was helpful to better understand the distribution characters of the dynamic stress of the brain tissue in the brain decelerating impact in a certain extent, and it could also provide some methods and experimental foundation to clarify the mechanical mechanism of the brain contrecoup injury which was often taken place in traffic accidental injury. Besides, the methods were of significance to research the biomechanism, diagnosis and prevention of the brain deceleration impacting injury.

Research on brain tissue mechanical Style in brain model deceleration Impact / 医用生物力学

Objective to research the mechanical style(compressive or tensile force)of the key site of brain tissue in brain deceleration impact.Method a transparent physical brain model with air bubbles was built and loaded on an upright brain decaler ation impacting expedmentel platform.Then,the moveable platform was made a free fall from a height of 400mm and impacted on the fixed platform,and the whole deceleration impacting process was recorded by a high-speed video camera.Using the serial pictures analyzing Software,the length change of the long ads(vertical to the impacting direction)and the short axis(in the impacting di-rection)of the air bubbles were analyzed and calculated.Result the length change of the long axis of air bub-ble with in site coup was smallerthan the absolute value of that of the short axis;while with the air bubble in the contrecoup site,the length change of the long axis was bigger than the absolute value of the short axis.Conclusions the results showed that the air bubble in the coup site mainly suffered from the tensile force vertical to the impacting direction and the air bubble in the contrecoup site mainly suffered from the compres-sive force in the impacting direction.Since the propeny of tensile resistance of the brain tissue is inferior to the property of compressive resistance of the brain tissue, the injury is often easier to occur in the contrecoup site than in coup site. The results were of significance to the research of biomechanical mechanism, diagnosis and prevention of the brain deceleration impacting injury.

Finite element analysis on moderate and severe brain injury of pedestrians in road traffic accidents / 中华创伤杂志

Objective To study the mechanics of moderate and severe brain injury of pedestrians in road traffic accident by establishing the virtual model of impact occipital bone injury.Methods The clinical data were used to analyze comlnon mode and characteristics of moderate and severe brain injury of pedestrians.Then,the corresponding finite element model built by using Hypermesh software was used to to analyze the changes of intracranial pressures and compare with injury characteristics by using Ls-Dyna soft-ware. Results The conlmon injury mode of moderate and severe brain injury of pedestrians wag the con-tact impact of occiputal part,characterized by"eontrecoup injury",mainly including subdural hemorrhage,extradural hemorrhage and contusion in the opposite parts to the impact point.The simtdation resuhs showed that when the impact was at right occiputal bone.the peak value of condensing force decreased from the right occipital lobe.to the left frontal lobe,while the peak value of tension increased gradually and reached maximum at the surface of left frontal lobe. Conclusions Moderate and severe brain injury of pedestrian is commonly caused by impacting the occiputal bone in road traffic accident.The tension deformation in frontal or temporal lobes and the distribution of vessels in grey matter may be main biomeehanies leading to "contrecoup injury".

Biomechanical changes and characteristics of impact temporal bone fractures / 中华创伤杂志

Objective To investigate the relationship of impact stress distribution and stress wave dissemination with temporal bone fracture. Methods Twelve donated fresh corpse were selected and impacted with driving force of 800 kPa, 1 200 kPa and 1 400 kPa to establish the model of impact temporal bone fractures. With aid of three-dimensional stereochemical structure image of 64-slice CT, the vitodynamic distribution and dissemination of impacted temporal bone was calculated by using computer simulation. Results (1) The instant velocity, acceleration and energy of impact as well as displace-ment scope of the hammer increased with higher driving force in the tempus. (2) Instantaneous impact of the temporal bone resulted in Von Mises stress concentration area around the impact point. The stress was weakened suddenly in the skull-brain tissue coupling place but later accumulated in the skull base. (3) Only ipsilateral linear fracture occurred when the driving force of impact was 800 kPa. While impact dif-ferent degrees of depressed fractures could be seen and one case showed secondary fracture of the opposite side when the driving force of impact was 1 200 kPa. The impact with driving force for 1 400 kPa begot complex ipsilateral fractures, secondary fracture of the opposite side and skull basal fracture. (4) Frac-ture line of the temporal bone accorded with impact stress concentration area. Conclusions All pa-rameters, stress distribution and dissemination of impact are in accordance with temporal bone fracture during impaet process of the temporal bone, which is of vital significance for diagnosis and protection of impact temporal bone fractures.

Development of portable body balance testing system for posture of standing and sitting / 中国康复理论与实践

@#ObjectiveTo develop a portable body balance testing system for posture of standing and sitting.MethodsAs the body sways, balance indicator fixed on the centre of head will change with the swaying. The tract of the swaying indicator will be translated to tract of the posture by the means of photo-electricity and image processing. The body balance function will be measured quantificationally after the tract is analysed.Results and ConclusionThe system has been developed. With the aid of this instrument, the body balance function of one volunteer pre-drinking and post-drinking has been measured and compared.

Ultra-structural changes of the lumbar spinal motor neurons after sciatic nerve injury induced by high-speed steel ball / 中国组织工程研究

BACKGROUND: What kind of traumatic changes could be observed in remote lumbar spinal cord after high-speed steel ball induced sciatic nerve injury?OBJECTIVE: To study the ultra structural changes of lumbar spinal cord motor neurons after the sciatic nerve injury due to high-speed steel ball.DESIGN: Retrospective randomized controlled study with experimental animals as subjects.SETTING: The field operation research institute of a military medical university college.MATERIALS: This study was carried out at the Ballistic Laboratory of Research Institute for Surgery from May 2001 to December 2002. Sixty-five SPF flap-eared rabbits of either gender weighing from 2.5 to 3.0 kg were provided by the Experimental Animal Center of Daping Hospital Affiliated to the Third Military Medical Univeristy of Chinese PLA. All the rabbits were divided randomly into normal control group( n = 5), firearms injury group (n = 30) and cutting injury group( n = 30) . The two latter groups were subdivided into one-day, three-day, one-week, two-week, 4-week and twelve-week groups with 5 rabbits in each group.METHODS: The rabbits in the firearms injury group were injured at the midpoint of lateral posterior body surface projection of the right sciatic nerve with 0. 38 g steel ball containing 0.65 g detonators. The right sciatic nerve was cut at the same injury level in the cutting injury group.MAIN OUTCOME MEASURES: The following pathologic changes of the lumbar spinal cord were observed with optical and electronic microscope at posttraumatic day 1, day 3 and week 1, week 2, week 4 and week 12 respectively.RESULTS: Micro-hemorrhage, neuron swelling and vacuoles were observed in the firearms injury group and the number of motor neurons decreased significantly, but these changes were unobservable in the cutting injury group.CONCLUSION: Compared with the cutting group, the injury to the spinal cord was severer in the firearms group and the survival neurons were less.

Research of Effects and Defense of High-power Microwave Radiation on Military Medical Equipment / 医疗卫生装备

The feature of HPM(high-power microwave) and its effect are briefly introduced.The destroying mechanism of HPM to different electronic medical equipment is described in detail.The reinforcement of HPM and effective measures are discussed.It is crucial to study the effects of high-power microwave radiation on military electronic equipment due to wide application of HPM in future military actions.

Development and application of a device for stretch-induced injury to cultured cell and testing system / 第三军医大学学报

Objective To develop a device for stretch-induced injury to cultured cells and measure the injury parameters.It makes possible to observe the changes of cell configuration and function directly after injury. Methods The device was developed based on aero-dynamical principle,and consisted of mini-type air compressor,electromagnetic valve,pressure transmitter,PGA amplifier,A/D converter and computer.The computer can accurately control the injury parameters.A new method and device were first introduced to measure the deformation rate and deformation degree of silastic membrance in the stretch induced cultured cell injury process.The device controlled by the computer was used to cause the astrocyte injury.The degree of cell injury was assessed qualitatively by electron microscopy,and quantitatively by lactate dehydrogenase(LDH) enzyme release and trypan blue staining.Results The experiment results showed that the injury of different levels could be reproduced by our device under the injury parameters we set.Conclusion The injury device and the measuring system meet the requirements of our design.The results suggested that the new device and the method were much better than those reported in foreign literature.It has the advantages of simple and convenient manipulation,high precision and real-time processing.It can be used for the cell-level experiment research.

Study on traffic injury of front crash in rabbits / 第三军医大学学报

Objective To study the mechanism and characteristic of traffic injury of front crash. Methods Thirty rabbits were divided randomly into 3 groups according to crash velocity. The initial velocity of GroupⅠ was 30 km/h, group Ⅱ 40 km/h, and group Ⅲ 50 km/h. The rabbits were fixed on the seats in a sitting position and the injury process were started by driving power system with the velocity and acceleration set primarily. The crashing velocity and deceleration were recorded by laser velocity measuring system and high speed camera system. The injury characteristics of rabbits were observed and then the AIS-ISS score was compared. Results During 1 hour after injury, all rabbits survived except one in group Ⅱ and three in group Ⅲ. No organ injury was found in group Ⅰ, but organ injuries in thorax and abdomen were found in group Ⅱ and Ⅲ. The score of AIS (MAIS) and ISS were (2.30?0.65), (14.50?2.10) in group Ⅱand (4.20?0.70), (36.40?4.58) in group Ⅲ respectively. Conclusion The velocity and deceleration of crash have impact on the injury character of animal, and the main injury organs are the thorax and abdomen in traffic injury of front crash in rabbits.

Pathological observation of the dog lungs after underwater blast injury / 第三军医大学学报

Objective To explore pathological changes of the dog lungs after underwater blast injury. Methods Lungs from 37 adult dogs were taken after different underwater blast explosions, and observed with gross examination, light microscopy (LM) and electron microscopy (EM). Results Pulmonary hemorrhage and edema were the main morphological changes. Under LM the alveolus space was seen to be filled with edematous fluid and bloody components. Part of alveolus walls were ruptured and fused into bigger cavities while under EM the mitochondria of alveolar epithelium were vacuolated and some of the capillary predominant endothelium were broken. Hemorrhage was the pathological feature of intestinal tract. Conclusion Severe pulmonary hemorrhage and edema may be the main cause of early death of dogs with underwater blast injury.