After one hind leg of the pig was wounded by the high-speed steel spheres the status of the animals was continuously monitored by determination of hemody-namics, blood gas, chest X-ray, serum T3, T4, fibronectin, protein content of lung lavage, lung weight, light and electromicroscopic examination etc. When the animals died or were killed 72 hours after injury, the pathologic examinations were carried out as soon as possible. It showed that there were various changes in above mentioned parameters, especially in those of the dead animals. The relationship between the incidence of RDS and trauma index-injury severity score (ISS) was discussed. In addition, the subclinical type of RDS was emphasised.

Bacterial endotoxins (LPS) are not only the major constituents of the outer membrane of Gram-negative (G -) bacteria, but also the toxic determinants for G - infection, which is closely related to human health and the development of diseases. Pattern recognition receptors (PRR) have been considered to be the important initial steps for cellular recognition of LPS and consequent initiation of LPS responses. Scavenger receptor, CD14, toll-like receptors, ?2-integrins and L-selectin have been shown to be involved in the clearance of LPS or LPS activation. LPS receptor may be a complex of multiple components. Different individual response to LPS is related to gene background. The gene polymorphism of LPS receptors and LPS-induced cytokines have been shown to contribute to LPS sensitivity, susceptibility and prognosis of sepsis.

With the continuous improvement in weaponry, especially explosive weapons, blast injury has become one of the most common war injuries. Underwater blast injury is a common war injury during combat around islands or fighting for beach-head. The wounding effects of underwater blast wave and the characteristics of underblast injury are quite different from that produced in air due to special physical features of water and the underwater pressure. We have investigated the injurious effects of underwater blast wave and its dose-effect relationship. In addition, some protective measures have been tested to prevent or alleviate underwater blast injury. All of these primary results have provided both experimental and theoretical foundation evidence for further researches in respect to the diagnosis, emergency care and protection against underwater blast injury.

Objective To explore the changed rules and the diagnositic methods of the cardisc functions after chest impact trauma(CIT).Methods The medals of moderate to severity CIT were established using BIM-Ⅱ Bio-impactor in 20 rabbits.The cardiac functions were examined with cardiac catheterization,single photon-emission computed tomography(SPECT)and the Doppler echocardiography at pre end post 1h,4h,8h and 24h after CIT.Results The cardiac functions were changed significantly after CIT.The expressions of the right ventricular dysfunctions mainly were systolic dysfuction while the left ventricular dysfunctions mainly were diastolic dysfunction after CIT.Conclustion All the cardiac catheterization、SPECT and the Doppler echocardiography are beneficial to the diagnosis of cardiac dysfunction afte CIT.The SPEGT is more exactitude and the Doppler echocardiography is more cheaper compared with non-invasive approaches.

BACKGROUND: There exists a close relationship between the expression of scavenger receptor(SR) and CD14 and the endotoxic lung injury. To further detect the expression of these two receptors and their relationship is helpful to disclose the receptor mechanism of lung inflammatory disequilibrium so as to provide a possible theoretical foundation for sepsis therapy.OBJECTIVE: To investigate the expression of CD14 and SR in murine alveolar macrophages and their effect after trauma and traumatic endotoxin challenge.DESIGN: Randomized and controlled experimental study.SETTING: Fourth Laboratory(a state key laboratory), Trauma, Burns and Combined Injury, the Research Institute of Field Surgery, Daping Hospital,the Third Military Medical University of Chinese PLA.MATERIALS: The experiment was completed in the Research Institute of Field Surgery of Daping Hospital of the Third Military Medical University of Chinese PLA from August 2001 to November 2001. Totally 63 Kunming mice with murine alveolar macrophages were used in the experiment.METHODS: The experimental animals were randomly divided into three groups including control group, trauma group and traumatic endotoxin challenge group. The model mice with both femur fracture and endotoxin challenge were used. Endotoxin at a dose of 5 mg/kg was injected one hour after fracture via tail vein and the dynamic expression of CD14 and SR in murine alveolar macrophages (AM) was detected.RESULTS: Six hours after trauma, the expression of CD14 and that of SR in AM showed the tendency of up-regulation and down-regulation respectively. Furthermore, the post-traumatic endotoxin challenge induced CD14up-regulation and SR down-regulation drastically. Correlation analysis indicated that CD14 and SR showed a significantly negative relationship.CONCLUSION: The study suggested that the dual modulation of CD14 and SR in AM is possibly related with the change of "self-control" to "out of control" of inflammatory reactions in the lungs after endotoxic challenge. The dual regulation of the effective antagonists CD14 and SR are helpful in further understanding lung injury and its repairing mechanism.

Objective To explore the changes and the significance of left ventricular functions after blunt chest trauma(BCT)in rabbits.Methods 36 rabbit models of BCT with BIM-Ⅱ Bio-impactor in were used to observe the changes of left ventricular functions and free calcium,free calmodulin and total calmodulin were detected at pre-injury,the 2nd,4th,8th,12th and 24th hour after injury.Results The cardiac function were impaired.The systolic functions of left ventricle were impaired and recovered during 4-12 hour after BCT.The diastolic functions of left ventricle were impaired but not recovered 24h after BCT.The free calcium and total calmodulin in myocardial cells were increased from the 4th hour,reached,peak at the 8th hour post-BCT(P＜0.01),and then decreased,but were still higher at the 24th hour post-BCT than that of pre-BCT(P＜0.05).The free calmodulin in myocardial cells was low and reached peak at the 8th hour after BCT(P＜0.01).There is remarkable positive correlation between free calcium in myocardial cells and LVEDP and dp/dtmax with cardiac function(P＜0.05,P＜0.01).Conclusion The cardiac function is obviously changed after BCT,especially the diastolic functions of left ventricle.The hish concentration of free calcium in myocardial ceils may be one of the reasons of cardiac dysfunction after BCT.

AIM: To explore the pathophysiological bases in the pathogenesis of the lasting emotional behavioral disorders following posttraumatic stress disorder (PTSD). METHODS: 240 male Wistar rats were divided randomly into 3 groups. Group SE ( n =96) for rats with PTSD-like behavior by constant pulsating current of 100 ?A with intratrain frequencies of 16 Hz, pulsating duration of 1 ms, train duration of 10 s and interstimulus interval of 7 min for 5 days with 8 times per day. Group CE ( n =96) for control with electrode implanted in hippocampus without stimulation, and Group NC ( n =48) for normal control. The activities of Na +-K +-ATPase and Ca 2+ -ATPase, levels of intracellular calcium and free calmodulin (CaM), and the total CaM expression were detected in hippocampi of experimental rats. RESULTS: The activities of Na +-K +-ATPase and Ca 2+ -ATPase in mitochondria of hippocampal cells in Group SE rats were significantly decreased at 48 h and 72 h after the last stimulation, respectively. The intracellular free calcium levels were increased, and the mean channel fluorescence of intracellular free CaM decreased remarkably at 72 h poststimulation, while the expression of total CaM was significantly elevated at 48 h after the last stimulation in hippocampi of Group SE rats. CONCLUSION: The lasting increased levels of intracellular free calcium and expression of Ca 2+ -CaM in hippocampus, as well as the dysfunction of Na +-K + pump and Ca 2+ -ATPase in mitochondria may play important roles in the long-term neuropsychological sequelae in PTSD.

Objective To evaluate the expressive varieties of Nogo-A mRNA in injured optic nerves of rats. Methods Reverse transcription polymerase chain reaction (RT-PCR) method was used to hemi-quantitatively analyze the levels of Nogo-A mRNA in the optic nerves 3, 7, 9, 15, 21, and 25 days respectively after injury. Results The level of the expression of Nogo-A mRNA was low in the normal optic nerves, while it was significantly high in the optic nerves 3 days after injury, and kept the high level still after 25 days. Conclusion The expression of Nogo-A mRNA in injured optic nerves is increased.

Objective To study the effect of application of vascular endoth el ial growth factor (VEGF) and anti-VEGF on the expression of fracture healing rel ated factors and observe the pathological changes at fractured site. Methods Fra cture models were established in 105 rabbits. All rabbits were randomly assigned into controlled group, VEGF treated group and anti-VEGF treated group. The fact ors related to fracture healing were detected, and pathological changes were obs erved at 8, 24, 72 h and 1, 3, 5, 8 weeks after fracture. Results After the appl ication of VGEF, BMP was expressed earlier and the express period was prolonged . On the contrary, anti-VEGF completely inhibited the expression of BMP in the f ractured ends. The fractured sites were filled with fibrous callus, cartilage ca llus and bony callus at the 3rd week and they were converted into woven bone at the 5th week. The fracture reached to normal healing at the 8th week in the VEGF treated group. Cellular necrosis increased in the earlier period in the VEGF po lyclonal antibody treated group, continuous focal necrosis was seen in the fract ured sites between 1st week to 5th week, vascularization reduced obviously at th e 3rd week. Conclusion Fracture healing is the result of mutual modulation and c oordination among many factors. VEGF may be an important factor which plays impo rtant role in the course of fracture healing.

Objective To study the expression law of zinc finger protein A20 mRNA of mouse liver tissues in the process of trauma with lipopolysaccharide (LPS) infection. Methods A total of 95 healthy mice (either sex, from Kunming, Yunnan province) with a mean body weight of 21 g (18-24 g) were randomized into 4 groups: control, trauma only (Group A), LPS only (Group B) and trauma plus LPS (Group C). The models with closed fracture of bilateral spines as well as endotoximia were made. The expression characteristics of zinc finger protein A20 mRNA of liver tissues were measured by reverse transcription-polymerase chain reaction (RT-PCR) and all result data expressed as total gray ratio of A20 mRNA to GAPDH mRNA (?s). Results In the control group, the A20 mRNA expressed at a low level. There was low expression of zinc finger protein A20 in the Group A at various time points, with no significant difference compared with the control group. After LPS infection, the expression of A20 mRNA in the Group B was elevated more obviously than that in the control group at 0.5 hour, reached peak during 0.5-2 hours and decreased after 2 hours. But expression of A20 mRNA at each time point was higher in the Group B than that in the Group A. In the Group C, after LPS infection, the expression of A20 mRNA was elevated more significantly than that in other two groups 0.5 hour, reached the highest level during 0.5-2 hours, much higher than that in the Group B (P