Objective To evaluate the effect of regional hypothermia on limb ischemia-reperfusion (I/R) injury in a rabbit model of hemorrhagic shock.Methods Eighteen healthy adult New Zealand white rabbits of both sexes,weighing 2.0-2.5 kg,were divided into 3 groups (n=6 each) using a random number table:sham operation group (S group),limb I/R group (I/R group) and regional hypothermia group (RH group).Rabbits were shot with 0.25 g steel ball with a 7.62 mm smoothbore at the middle and lower 1/3 of the left hindlimb in I/R and RH groups.When the blood pressure was stable for 30 min after injury,blood was drawn via the right femoral artery at a rate of 2 ml/min until mean arterial pressure decreased to 45-50 mmHg.Then a rubber tourniquet was used to ligate left hindlimbs 10 min later.The injured limb was cooled down for 4 h after applying tourniquet to maintain the subcutaneous temperature at 9-11 ℃ in group RH.After tourniquet was applied for 4 h,perfusion was restored and lasted 6 h.After catheterization (T0) and at 2,4 and 6 h of reperfusion (T1-3),blood samples were collected from the right femoral artery for blood gas analysis and for determination of tumor necrosis factor-α (TNF-α),interleukin-2 (IL-2) and IL-6 concentrations in serum (by enzyme-linked immunosorbent assay).The animals were sacrificed at T3,and tissues around the margin of the inferior lobe of right lung were obtained for examination of the pathological changes which were scored and for determination of wet to dry weight ratio (W/D ratio).Results Compared with group S,the respiratory rate was significantly increased and PaCO2 was decreased at T2,3,the pathological score and W/D ratio were increased,and the concentrations of TNF-α,IL-2 and IL-6 in serum were increased at T1-3 in I/R and RH groups (P＜0.05).Compared with group I/R,the respiratory rate was significantly decreased and PaCO2 was increased at T2,3,the pathological score and W/D ratio were decreased,and the concentrations of TNF-α,IL-2 and IL-6 in serum were decreased at T1-3 (P＜0.05),and the pathological score was significantly attenuated in group RH.Conclusion Regional hypothermia can reduce limb I/R injury in a rabbit model of hemorrhagic shock,and the mechanism may be related to inhibiting systemic inflammatory responses.

Objective To investigate the distribution and changes of microorganisms on the skin of submariners under a chronically closed environment , and provide reference for targeted medical support .Methods One hundred and twenty-two samples were collected using swab.After culture and isolation, the microbes were identified by matrix-assisted laser desorption/ionization time of flight mass spectrometry ( MALDI-TOF-MS) .Results A total of 52 types of 229 bacteria and 2 types of fungi were isolated . Major opportunistic pathogens included Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter cloacae, while major dwelling bacteria included Micrococcus luteus, Oslo Mora bacteria, Acinetobacter, Staphylococcus epidermidis, and Serratia marcescens.Compared with the early period of the task, major opportunistic pathogens and dwelling bacteria were significantly increased in the middle and late period of the task .Conclusion The skin microbes of the submariners are investigated , targeted drugs need to be prepared for daily medical support and war trauma .

In the future,anti-ship missiles(ASM) will be major weapons in the sea war.It is very important to handle the profile of the casualties aboard warships attacked by ASM for development of naval health service.The statistical result shows there is a greater chance of casualties but less chance of warships being sunken by ASM.Besides,medical staffs should pay more attention to the first aid for victims due to blast,burn,smoke inhalation and penetration while the danger of the sea water immersion should not be ignored.

Objective To study the characteristics of craniocerebral injury caused by the handgun bullet impacting on the bulletproof helmet.Methods Fourteen healthy landrace pigs were involved and randomly divided into injury group(n =9)and control group(n =5).The landrace pigs of the injury group were shot vertically on the head under the protection of helmet plate with 9 mm handgun bullet at velocity of 360 m/s.While the landrace pigs of the control group were dealt with the same process as the injury group except for use of unarmed handgun bullet of the same ammunition dose.The changes of vital sign in the early period and the retina injury at two hours after injury were observed.Porcine cerebrospinal fluid (CSF)at pre-injury and at three hours post-injury were obtained for investigating the levels of neuron specific enolase(NSE)andαⅡ-spectrin protein.Then,the landrace pigs were sacrificed and dissected to examine the general morphological changes of the brain.The brain cortex was taken,fixed and stained with hematoxylin-eosin for microscopic observation.Results The landrace pigs in the injury group manifested decrease of the blood pressure and increase of the heart rate and respiratory rate in the early stage after injury.General morphological observation found retinal hemorrhage(3/9),skull fracture(3/9)and brain surface damage including local impact lesion(9/9)and contrecoup lesion(9/9),with severe impact lesion than contrecoup lesion.Optical microscopic observation revealed acute injury of the cerebral cortex neuron both on the impact and contrecoup locations.The concentrations of NSE and αⅡ-spectrinwere significantly increased in CSF three hours after injury(P ＜ 0.05).Conclusions The handgun bullet impacts on the pig head protected by the bulletproof helmet may induce blunt craniocerebral injury in the early period,with severe impact lesion than contrecoup lesion.Therefore,traumatic brain injury of the soldiers armed with the helmets should be stressed and managed early.

AIM: To study the effects of tumor necrosis factor-α (TNF-α) on the transcriptional activity of nuclear factor-erythroid 2-related factor 2 (Nrf2) in pulmonary microvascular endothelial cells. METHODS: Rat pulmonary micro-vascular endothelial cells (PMVECs) were cultured by lung tissue block pasted methods, and identified immunocytochemically using Ⅷ factor-related antigen. The cells were treated with different doses TNF-α (prepared in serum-free medium) for 4 h. Subcellular localization and levels of Nrf2 in PMVECs were observed with immunocytochemical methods. Nuclear extract were obtained to assayed transcriptional activity of Nrf2 with EMSA. Total RNA were isolated to assay the mRNA expression of Nrf2 by RT-PCR. RESULTS: The protein level of Nrf2 in the nuclei and transcriptional activity increased dose-dependently in PMVECs after treated with TNF-α at concentrations of 2.5, 5.0 or 10.0 μg/L. However, the protein level of Nrf2 in nuclei and transcriptional activity decreased dose-dependently in PMVECs after treated with TNF-α at concentrations of 20 or 40 μg/L. No different mRNA expression of Nrf2 in PMVECs treated with TNF-α at all concentration above was observed. CONCLUSION: Transcriptional activity of Nrf2 increases in PMVECs treated with low or moderate doses of TNF-α and decreases in PMVECs treated with high doses of TNF-α.

Objective To study autocrine characteristics of substance P(SP)in epidermal stem cells(ESCs). Methods In vitro cultured ESCs was stimulated by exogenous SP.Then,the expressions of SP gene,protein and exogenous SP protein in ESCs and the supernatant fluid were detected by immunofluorescence,ELISA,Western blot and real-time PCR. Results After stimulation by exogenous SP,the expression of SP protein in ESCs and supernatant fluid was up-regulated and reached peak at 24th hour,with higher concentration than the added SP.The gene expression of SP was up-regulated to the peak 6 hours after stimulation by SP.Both expression of gene and protein remained unchanged after the natural killer cell receptor Was blocked even by stimulation with exogenous SP. Conclusion Anticrine of SP of ESCs can be induced by exogenous SP.

BACKGROUND:It has been reported that blast wave and haze can lead to hemodynamics disturbance.However,studies on blast-haze combined injury on hemodynamics changes are few.OBJECTIVE:To investigate the effect of blast-haze on the hemodynamics parameters during early period following cabin explosion,additionally,to evaluate the feasibility of brain natriuretic polypeptide(BNP) to serve as the damage criterion in early detection.DESIGN,TIME AND SETTING:Randomization,experimental observation of animal was performed at the Research Institute of Surgery,Daping Hospital,Third Military Medical University between August 2006 and August 2007.MATERIALS:One hundred and four healthy,male SD rats were randomly divided into the normal control(n=8),blast injury(n=48),and combined injury(n=48) groups.METHODS:The rats were fixed in the cabin according to the position of the war sitting,0.4 g cyclotrimethylene trinitramine were used to explosion in the centre of the cabin.The rats in the blast injury and combined injury group were took out immediately and 100 s after explosion,respectively.No treatment was performed in the normal control group.MAIN OUTCOME MEASURES:The heart function changes,the level of BNP,as well as the pathological change of lung tissues were analyzed by ELISA,double antibody sandwich method,and the microscope at 1,3,6,12,24,and 72 hours after injury,respectively.RESULTS:Compared with the normal control group,there were significantly differences of pathomorphological changes in the blast injury and combined injury groups,even,more severe in the combined group than the blast injury group.The level of BNP at each time point was higher than that of the normal control group(P

BACKGROUND: To establish experimental animal model for rapid evaluation of combined wound with seawater immersion so as to benefit wound healing and recovery.OBJECTIVE: To explore the plan of simple evaluation of combined wound with seawater immersion.DESIGN: Group division and controlled experiment was designed.SETTING: Second Department of Orthopaedics, the 113 Hospital of Chinese PLA; Research Institute of Surgery, Daping Hospital, Third Military Medical University of Chinese PLA MATERIALS: Totally 32 health hybridized adult dogs were employed,mass weighted varied from 12 to 15 kg, of either sex.METHODS: The experiment was performed partially in the specific sea area of the Fifth and Sixth Room , Research Institute of Surgery of Daping Hospital of the Third Military Medical University of Chinese PLA from October 2001 to June 2002. The dogs were randomized into burn-blast combined wound group and projectile-burn combined wound group and each group was subdivided into immersion group (10 dogs) and the control (6 dogs). Burn-blast combined wound group: The model of burn and mild blast injury was prepared. In the control, the dogs were put in a room at 25 ℃ directly after injury; But in immersion group, the dogs were immersed immediately in simulated seawater with holder. Projectile-burn combined wound group: The model of burn and mild projectile injury was prepared. The managements were same as the previous after injury in the control and immersion group. The change of physiologic indexes was observed in 28 hours after injury. The indexes related to death were picked up for correlative analysis and establishing wound scoring scale, inducing body temperature, heart rate, mean arterial pressure (MAP), chloride concentration, PaO2 and causative factor, 0-5 score were designed, the higher the score was, the higher mortality would be.MAIN OUTCOME MEASURES: ① Analysis of dead cases in each group. ② Wound scoring. ③ Verification of wound in scoring scale.RESULTS: 32 dogs all entered result analysis. ① Analysis of dead cases and relationship: Totally, 12 dogs were died. The peak of death was in 10-12hours, no matter the immersion happened or not. 5 indexes were associated significantly with death, named body temperature, heart rate, MAP, PaO2 and chloride concentration (P ＜ 0.05). ② Comparison of wound scoring, predictive mortality and actual mortality in each group: The results in burn-blast control were (5.89±3.25) score, 0 and 17% successively. Those in projectileburn control were (6.78±2.02), 25% and 33% successively. Those in burn blast immersion group were (9.50±4.20) scores, 50% and 30% and those in projectile-burn immersion group were (11.13±3.57) scores, 50% and 60%.CONCLUSION: ① The established scoring scale is apt to obtain common physiological indexes so as to evaluate the wound rapidly, which is applica ble for either seawater immersed cases or non-immersed cases, indicating extensively applications. ② The correction of evaluation is acceptable with verification. ③ The scale is based on animal experimental data, for which,it is still different from the one of real wound evaluation.

Objective To study the influence and mechanism of seawater immersion on endothelial cell injury sustained by burn firearm combined injury to improve the early therapeutic efficacy. Methods The dogs with burn firearm combined injury were randomly divided into two groups: immersion group and control group. In immersion group, the dogs were immersed in seawater for 4 hours, then taken out from seawater. Blood samples were collected from central vein at 4 h, 7 h, 10 h, 20 h and 28 h following wound for the detection of changes of the circulating endothelial cells (CEC) and von Willebrand Factor (vWF). The same procedures except immersion were performed in the control group. Results The levels of CEC and vWF elevated at 4 h and 7 h following wound in control group( P

Objective To study the effect of sensory nerves on the expression of epidermal growth factor(EGF), basic fibroblast growth factor(bFGF) by fibroblasts in the granulation tissues in skin wound healing. Methods In vivo and in vitro studies were conducted. Fifty wistar rats were randomly divided into capsaicin group and control group. The rats in the capsaicin group were subcutaneously injected with neurotoxin dose of capsaicin(50 mg/kg for 3 days) to chemically destroy the sensory nerves. Full thickness skin incisive wound was made on the rat′s back on 8th day after last injection. The contents of substance P(SP), which was mainly released from afferent sensory nerve terminal, and EGF, bFGF in granulation tissue of skin lesion were determined using immunohistochemistry combined with computerized imaging analysis on 3rd, 6th, 9th, 12th days after the incision. In the control group no capsaicin was injected. In the in vitro study the fibroblasts from granulation tissue of rats were cultured with different doses of SP(10-9 ~ 10-5 mol/L), and the protein expression of EGF, bFGF by cultured fibroblasts was determined using Western blot. Results Immunoreactive SP was not only found around the small blood vessels and in the intercellular space, but also in the cytoplasm of fibroblasts in granulation tissue. SP content and the protein expression of EGF, bFGF in granulation tissue decreased in the capsaicin group, compared with those in the control group, which indicated that SP(10-7 mol/L) added into the culture medium for fibroblasts could upregulate the levels of EGF, bFGF expression. Conclusions Protein expression of EGF and bFGF by fibroblasts in granulation tissue in skin wound healing might be related with the SP released from sensory nerves.