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Radionuclide-contaminated wounds are common in medical response to nuclear emergencies, which have different manifestations in different types of accidents. Medical treatment is the key part of the response. Based on the drill experience gained from medical response to nuclear emergencies, the authors summarize the research advances in radionuclide-contaminated wounds in recent years, mainly involving the biokinetic characteristics, medical response, surgical debridement, and prevention and treatment of internal contamination of radionuclide-contaminated wounds; the authors summarize the key points of technical operations and provide suggestions on improvements in the drills. The authors believe that medical treatment of radionuclide-contaminated wounds requires highly compatible integration of the practical skills from clinical medicine and radiological knowledge; emergency response, surgical debridement, and prevention and treatment of internal contamination all together constitute an integrated rescue and treatment strategy with internal logic correlations. However, targeted improvements are needed to achieve desired effects in the drills.
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Bleeding caused by ionizing radiation involves many factors, the mechanism is complicated and the management is difficult. Bleeding is recognized as one of the main causes of death after ionizing radiation. In this paper, we summarize the pathophysiological mechanisms of ionizing radiation bleeding syndrome (IRBS) from the aspects of platelet abnormality, coagulation disorder and vascular damage. Besides, we expound the clinical characteristics of IRBS in terms of the degree, time and site of the bleeding. Combined with experimental results, we put forward ideas and possible approaches for the treatment of IRBS, and the key factor is to promote the recovery of megakaryocytes and rapid platelet production after radiation exposure.
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Objective To investigate the effects of G-CSF-mobilized autologous stem cells in the prevention of radiation pulmonary injury.Methods Mice were divided into control group,irradiation group and treatment group.Mouse model of pulmonary fibrosis was established by exposing chest to a single dose of 14 Gy.Animals in the treatment group received recombinant human G-CSF (250 μg/kg daily for 5 d) before the irradiation in order to mobilize autologous stem cells in vivo.The general condition and mortality were documented after radiation injury.The pathological study with histological scoring,Masson staining and Sirius red staining with polarized light analysis were used to identify lung injury and the potential benefit of stem cell mobilization.Results Local chest irradiation of a single dose of 14 Gy was a suitable dose to create radiation-induced pulmonary fibrosis in mice.The death rate was 37.5％,which mainly happened around 11 weeks after injury.In contrast,all of the animals in G-CSF treated group survived.The ratio of lung to body mass was significantly increased in both irradiation group and treatment group (F =23.20,P＜0.05) around 3 months after the injury,with a higher ratio in irradiation group than that in treatment group (P＜0.05).Histological scoring for alveolar inflammation at 3 months after injury revealed statistically significant difference in irradiation group and treatment group compared with control group (F=11.93,P＜ 0.05).At this time point,the pathological observation showed lung tissue degeneration and necrosis with alveolitis and interstitial inflammation,as well as fibroblasts proliferation and focal collagen deposition in alveolar septa.At 4 month after the injury,the inflammation ininterstitial tissue was receded,but fibrosis and collagen deposition were significantly increased.In addition,at 3 and 4 months afterinjury,the pulmonary fibrosis was aggravated in irradiation group (F=28.73,16.85,P＜0.05),and significantly alleviated in the treatment group (P＜0.05).The similar results were confirmed in collagen content analysis (IOD) by Sirius red staining and image analysis (F =17.70,17.79,P＜ 0.05).Conclusions Autologous mobilization of stem cells could prevent the death of radiation-injured animals possibly by alleviating early lung injury and interstitial inflammation as well as the late pulmonary fibrosis,suggesting a therapeutic potential of autologous stem cell mobilization in radiation pulmonary fibrosis.
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Objective To observe whether dermal multipotent stem cells (dMSCs) treated with platelet-derived growth factor-AA ( PDGF-AA )could distribute more frequently to the bone marrow in rats of total body irradiation (TBI).Methods Male dMSCs were isolated and 10 μg/L PDGF-AA was added to the culture medium and further cultured for 2 h.Then the expression of tenascin-C were examined by Western blot, and the migration ability of dMSCs was assessed in transwell chamber.The pre-treated dMSCs were transplanted by tail vein injection into female rats administered with total body irradiation, and 2 weeks after transplantation, real-time PCR was employed to measure the amount of dMSCs in bone marrow.Non-treated dMSCs served as control.Results PDGF-AA treatment increased the expression of tenascin-C in dMSCs, made (1.79 ± 0.13) × 105 cells migrate to the lower chamber under the effect of bone marrow extract, and distributed to bone marrow in TBI rats, significantly more than ( 1.24 ± 0.09) ×105 in non-treated dMSCs (t = 8.833, P ＜ 0.0l ).Conclusions PDGF-AA treatment could enhance the migration ability of dMSCs and increase the amount of dMSCs in bone marrow of TBI rats after transplantation.
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Objective To explore the protective effect of atorvastatin on irradiated endothelium and the thrombomodulin(TM)expression.Methods Cultured human coronary artery endothelial cells(HCAEC)and human umbilical vein endothelial cells(HUVEC)were treated by atorvastatin at the final concentration of 10 μmol/ml for 10 min,and then irradiated with 2 and 25 Gy.Cell cycles status and TM expression were quantitatively measured by flow cytometry 24 hours after irradiation.Protein C activation in endothelial cells was also assessod.Results After administration with atorvastatin for 24 h,the TM expression increased by 77%,59% and 61% in normal control group,2 Gy group and 25 Gy group,respectively(t=27.395,26.420,58.065;P=0.000).The protein C levels decreased by 23% and 34% compared with the normal group post-irradiation to 2 and 25 Gy,but increased by 79% and 76% compared with the irradiated control group after administration with atorvastatin.The rates of cell apoptosis decreased by 6% and 16% in 2 Gy and 25 Gy groups,respectively after administration with atorvastatin for 24 h(t=4.178,17.863;P=0.000).Conclusions Atorva statin can protect endothelia cell from irradiation-induced apeptosis by increasing TM expression and protein C activation.
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Objective To observe whether the transplanted dermal multipotent stem cells(dMSCs)transfected by adenovirus vector of CXCR4(Adv-CXCR4)can distribute more frequently to the wound of rats with combined wound and irradiation injury.Methods dMSCs transfected by Adv-CXCR4(group A),or transfected by adenovirus vector of green fluorescent protein(group B),and non-transfected dMSCs were labeled with 3H-TdR and then transplanted into combine-injured rats.The amount of dMSCs in wound were determined by liquid scintillation,and wounds healing process was observed by measuring the remaining wound area.Results From the 5th day after transplantation,the amount of dMSCs in the wound of group A accounted for 1.95%-3.85% of the total transplanted dMSCs,significantly greater than those in group B and group C,which accounted for 1.07%-1.86% of the total transplanted dMSCs.The remaining wound area in group A was smaller than those in group B and group C from day 12 after injury,and the healing time of group A was 1.5 day ahead than group B and group C.Conclusions dMSCs transfected by Adv-CXCR4 distributes more frequently to the wound of combine-injured rats and could accelerate wound healing.
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BACKGROUND: Human amniotic membrane (HAM) contains various ingredents such as collagen, glycoprotein,proteoglycan, integrin and laminated body, and so on, and expresses many kinds of growth factors and mRNA-associated proteins. And these ingredents can supply abundant nutriments for cellular proliferation and differentiation, and benefit cells to grow and propagate. Whether or not HAM can load porcine bone marrow-derived mesenchymal stem cells (BMSCs) to well grow on it deserves to be further investigated.OBJECTIVE: To set up a method of tissue engineering of human amniotic membrane loading porcine BMSCs and observe the morphological characteristics of growth and proliferation of BMSCs seeded on HAM.DESIGN: Randomized controlled observation.SETTING: State Key Laboratory of Trauma, Burn and Combined Injury, General Institute of Combined Injuries, Academy of Preventive Medicine, Third Military Medical University of Chinese PLA.MATERIALS: This experiment was carried out in the State Key Laboratory of Trauma, Burn and Combined Injury,General Institute of Combined Injuries, Academy of Preventive Medicine, Third Military Medical University of Chinese PLA between January and November 2003. Three Guizhou minipigs of either gender, aged 2 to 3 months, weighing from 6 to 8 kg, were provided by the Experimental Animal Center, Third Military Medical University of Chinese PLA. Main reagent:ISCOVE'S modified DULBECCO'S medium (IMDM) culture medium (Hyclone, USA); high-quality fetal bovine serum PAA (Germany); haematoxylin (China); Eosin B (Sigma, USA) and OCT embedding medium (USA). Main instruments: BX51 stereoscopic fluorescence microscope (Olympus, JaPan); IX70 inverted fluorescence microscope (Olympus, Japan);cryostat (2700-Frigcut, Germany); myeloid puncture needle (Jiangsu); superclean bench (Sujing Bloc Antai Company);CO2 constant-temperature incubator (QUEUE, USA).METHODS: HAM was prepared as previously described. The BMSCs of Guizhou minipigs isolated and cultured according to method described previously were primarily cultured and passaged, then they were inoculated to the stromal surface of HAM at different densities (0.84×105 cells/cm2,1.54×105 cells/cm2,2.75×105 cells/cm2); The growth and proliferation of BMSCs of different densities were observed under an inverted microscope and scanning electron microscope; BMSCs of the second or the third passages were inoculated on HAM held with tissue-holding device at a density of 1.54×105 cells/cm2, and they were cultured for 18 days at most. The HAM was daily rolled, sliced and stained by HE for observing the growth of BMSCs loaded on HAM under the light, scanning and transmission electron microscopes.MAIN OUTCOME MEASURES: The growth of BMSCs on HAM was examined at different densities and different time points.RESULTS: ① Comparison of growths of BMSCs promoted by different densities of HAM: BMSCs,which were planted on HAM at the density of 0.84×105 cells/cm2 were irregular and scattered under an invert microscope. Distances between BMSCs were biggish. BMSCs seeded on HAM at the density of 1.54×105 cells/cm2 were regular in arrangement and moderate in density, with clear cell outline and good cell activity before 24 hours, and seeded at the density of 2.75×105 cells/cm2 were congested with many nonattached cells and the longer the growing time of the cells was, the more the cellular debris were observed. BMSCs,which were planted on HAM at the density of 0.84×105 cells/cm2 under the scanning electron microscope, scatted on HAM presented in shapes of irregular, long, thin and flat polygon. Their membrane protuberances presented in shapes of thick and thin, and the distances between cells were biggish. BMSCs,which were planted on HAM at the density of 1.54×105 cells/cm2 have similar appearance of their bodies and membrane protuberances, and the membrane protuberances were more compared with the BMSCs planted at the density of 0.84×105 cells/cm2. Their membrane protuberances intercrossed each other, and the margin of some BMSCs overlapped each other. BMSCs planted at the density of 2.75×105 cells/cm2, arraved on HAM crowdedly and overlappedly with many debris. Their membrane protuberances were not obviously. The margin of some BMSCs was overlapped.② Comparisonof growths of BMSCs promoted by HAM at different time points: Under the inverted microscope, the BMSCs adhered quickly to HAM after being incubated for about 30 minutes. All of BMSCs adhered to HAM within 24 hours, and formed monolayer on it within 48 hours, and grew densely on HAM after being cultured for 4 to18 days. Under the light and electron microscopes, HE results revealed that BMSCs adhered tightly and grew on HAM in different arrays, such as emitting, whirlpool or parallel,and their nuclei located in middle, dense in staining, were big and clear. The shapes of BMSCs were comparatively consistent on HAM. HAM loaded with BMSCs grew 4 days, and BMSCs covered HAM completely. The densities of BMSCs on HAM were suitable, and their bodies were large, and presented irregular, long,thin and flat polygon under the scanning electron microscope. The margin of some BMSCs overlapped each other. The protuberances of cellular membrane of BMSCs were abundant in the shapes of thick and thin. Some protuberances intercrossed each other in the shape of net. BMSCs adhered tightly to HAM through these protuberances. HAM loading BMSCs grow 4 days; most of BMSCs grew on HAM in double layers with the shapes of cambiform under the transmission electron microscope, Their nucleoli were clear. The protuberances of cellular membrane of BMSCs, which situated at two sides of nuclei and overlapped each other, were long. Most of chromatins of BMSCs were autosome.Abundant organell such as rough endoplasmic reticulum (RER),mitochondria could be observed in BMSCs.CONCLUSION:HAM is able to promote the proliferation of BMSCs significantly. BMSCs may be cultured on HAM ex vivo.HAM is a good carrier of BMSCs.
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BACKGROUND: Bone marrow mesenchymal stem cells (BMMSCs) can be induced differentiating into osteoblasts and chondroblasts, DNA methylate depressant 5-azacytidine can induce BMMSCs expressing myogenic regulating factors: Myf5 and myopoietin, which involving in the differentiation of BMMSCs into myoblasts.OBJECTIVE: Muscular traumatic fluid containing the highest protein content was screened out and co-cultured with BMMSCs,in order to explore the inductive effect on the proliferation and myogeneis of BMMSCs.DESIGN : Standardized comparative study.SETTING .:At State Key Laboratory of Trauma, Bums and Combined Injury,Institute of Combined Injury, Medical College of Preventive Medicine, Third Military Medical University of Chinese PLA.MATERIALS: Muscular traumatic model was established on 18 Balb/C pure rats for the extraction of muscular traumatic fluid, the inductive effect of the fluid on BMMSC was then compared with 5-azacytidine.METHODS:This study was carried out at State Key Laboratory of Trauma,Burns and Combined Injury, Institute of Combined Injury, College of Preventive Medicine, Third Military Medical University of Chinese PLA from April 2001 and September 2003. Bradford colorimetric was used to detect the protein content in the muscular traumatic fluid, and the fluid with the highest protein was used to co-culture with BMMSC, whose effect on the proliferation of BMMSC was measured with MTT methods at day 0, 3, 6, 9, 12, 15.RT-PCR technique was used to detect the expression of myopoietin at day 6,with its myogenic effect compared with that of 5-azacytidine.fluid on BMMSC.eration of BMMSC: the proloferative activity of BMMSC in traumatic fluid genic effect of traumatic fluid on BMMSC: myopoietin could not be found expressed in traumatic fluid group, but strongly expressed in 5-azacytidine group.CONCLUSION: Muscular traumatic fluid can promote the proliferation of BMMSC, but has no myogenic effect.
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BACKGROUND: As a kind of semitransparent membrane, human amniotic membrance contains many kinds of nutrients, which is a good biological material loaded with keratinocytes.OBJECTIVE: To construct epidermal substitute of the skin from human amniotic membrane loaded with porcine keratinocytes and examine the morphological characteristics of the growth and proliferation of keratinocytes seeded on human amniotic membrane.DESIGN: Single sample study and repetitive measured observation based on the cells.SETTING: Institute of Combined Injuries of Chinese PLA, Academy of Preventive Medicine, Third Military Medical University of Chinese PLA.MATERIALS: The experiment was completed in the State Key Laboratory of Trauma, Burn and Combined Injury and Institute of Combined Injuries of Chinese PLA, Academy of Preventive Medicine, Third Military Medical University of Chinese PLA from January to November 2001. Porcine keratinocytes was collected from Guizhou minipigs aged 3 weeks.METHODS: The primarily cultured keratinocytes of Guizhou minipigs were subcuhured, expanded and bred on the stroma surface of human amniotic membrance at the density of 1.63 × 105/cm2. The growth and proliferation of keratinocytes were observed under inverted microscope every day. From the 3rd day and the 15th day after being cultured, the growth of keratinocytes on human amniotic membrane was examined under light microscope and electron microscope.MAIN OUTCOME MEASURES: The growth of keratinocytes on human amniotic membrane was examined RESULTS: Keratinocytes evidently adhered to the stroma surface of human amniotic membrane about 30 minutes after being cultured, which was observed under inverted microscope. Most keratinocytes grew and adhered to the stroma surface of human amniotic membrane within 24 hours. Monolayer of keratinocytes formed and completely covered human amniotic membrane within 3 days. It was observed under the light microscope that the monolayer of keratinocytes adhered to human amniotic membrane and arrayed tightly. The keratinocytes presented in the shape of polygon, and plasmalemmas of keratinocytes formed many pseudopods under the observation with scanning electron microscope. Keratinocytes adhered to human amniotic membrane well and with many keratinofilaments in them under the observation with transmission electron microscope. Keratinocytes arrayed on human amniotic membrane densely with many cellular debris and some keratinocytes formed cavitations in them due to aging after growth for 15 days under the observation with inverted microscope.CONCLUSION: Human amitotic membrane is a good carrier of keratinocytes cultured on it in vitro, and is able to promote the proliferation of keratinocytes significantly. However, when keratinocytes were loaded on the human amniotic membrane for 15 days, some keratinocytes formed cavitations in them due to aging.
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<p><b>OBJECTIVE</b>To study the effects of dosages of total body irradiation on the healing process of cutaneous wounds and to observe the changes of wound area at different periods after injury.</p><p><b>METHODS</b>The entire body irradiation from a (60)Co gamma-ray source was performed on Wistar rats. The single dosage varied from 1 to 8 Gy. Within 1 h after irradiation, two whole thickness circular cutaneous wounds corresponding to 2.5% of total body surface area (Phi = 22 mm) were produced on the back of the animals (combined injury groups). Same wounds were produced on rats with no irradiation (single wound group). Wound healing was observed at different points after injury.</p><p><b>RESULTS</b>After total body irradiation with the dose of 1, 2, 3, 4, 5, 6, 7 or 8 Gy, the wound healing was obviously retarded as the dosages increased. The wound area remained was larger in the large dosage groups than in the small dosage groups. Seven days after injury, there was 33.5% wound surface left unhealed in the single wound group, whereas in the combined injury groups, 35.4%, 38.1%, 41.6%, 48.8%, 53.9%, 63.7%, 69.2% and 73.9% of the wound surfaces remained unhealed, respectively. Statistical analysis showed marked correlations between the various times after total body irradiation and various dosages to the percentage of unhealed wound surface. Nine dose-effect relation formulae were deduced according to the statistical results.</p><p><b>CONCLUSIONS</b>In soft tissue trauma combined with radiation injury, the delay of wound healing is related to the dose of radiation inflicted. It is also related to the time between injury and time of observation.</p>
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Animaux , Femelle , Mâle , Rats , Relation dose-effet des rayonnements , Rat Wistar , Facteurs temps , Irradiation corporelle totale , Cicatrisation de plaie , Effets des rayonnementsRÉSUMÉ
Objective To clone platelet-derived growth factor A chain (PDGF-A) gene and insert PDGF-A gene into. Enhanced green fluorescent protein (EGFP) vector and then transformed into dermis-drived mesenchymal stem cells (DMSCs). Methods cDNA clones encoding human PDGF-A gene were isolated from a human hepatoma cell line mRNA by reverse transcription-polymerase chain reaction (RT-PCR). The PCR amplified fragment of PDGF-A gene was cloned into pMD18-T vector. The eukaryotic expression vector pEGFP-N1/PDGF-A was constructed by subcolone PDGF-A gene into pEGFP-N1 vector. PDGF-A gene was transfected into DMSCs with the help of Fugene 6 transfection reagent. Results Full cDNA sequence encoding human PDGF-A gene had been cloned, which sequence was consistent with the reported sequence in GenBank by sequence assaying. Conclusion cDNA sequence encoding human PDGF-A gene was successfully cloned into pEGFP-N1. The transient expression of PDGF-A gene in DMSCs has been realized.
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Objective To obtain skin seed cells which can highly express active vascular endothelial growth factor 165(VEGF165) so as to promote refractory wound healing by gene therapy in combination with cell engineering.Methods After pIRES2-EGFP-hVEGF165 was transfected into dermal mesenchymal stem cells(DMSCs) by lipofectin,the expression of VEGF mRNA was detected by RT-PCR,VEGF protein in the supernatant and in the cells were assayed by enzyme-linked immunosorbent assay(ELISA) and Westen blotting respectively.To evaluate the activity of VEGF secreted by transfected DMSCs,hECV304 was cultured with the supernatant of transfected DMSCs and its proliferation activity was analyzed by MTT assays.Meanwhile,the proliferation activity of VEGF-transfected DMSCs and non transfected DMSCs was investigated by MTT.Results The results of RT-PCR,ELISA and Western blot demonstrated that the expression of VEGF in transfected DMSCs was about 1.6 times than that of control DMSCs.The product not only enhanced the proliferation of hECV304 but also increased the proliferation of transfected DMSCs.Conclusion The plasmid pIRES2-EGFP-hVEGF165 is successfully transfected into DMSCs with the aid of lipotransfection,and hVEGF165-transfected DMSCs might high-efficiently secrete highly active VEGF165.
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Objective To detect whether mice bone marrow mesenchymal stem cells(BMSCs)can contribute to the regeneration of hepatocytes in bone marrow chimeric mice.Methods Female recipient mice(C57BL/6J)underwent whole body gamma-ray irradiation with a dose of 10 Gy to ablate their bone marrow,followed by immediate tail vein injection of BMSCs isolated from male GFP transgenic mice.Animals were killed at different phase points:1 week,1 month,and 3 months.Using fluorescence microscope we directly observed GFP-positive cells in the liver frozen sections,and we also prepared the parafilm sections to detect the GFP-positive cells and the coexpression of GFP and Alb,CK18 by immunohistochemistry and immunofluorescence respectively.Results We found numerous GFP-positive cells in recipient mice liver at 1 week after BMSCs transplantation,some at 1 month and seldom at 3 months.There were some cells coexpressing GFP and Alb,CK18 at all the phase points.Conclusion Allotype BMSCs can differentiate into Alb and CK18 positive hepatocytes in bone marrow chimeric mice,which will become an ideal cell resource for liver tissue project.
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<p><b>OBJECTIVE</b>To investigate therapeutics for and the pathological basis of combined radiation and burn injuries.</p><p><b>METHODS</b>Combined radiation and burn injuries on mice and rats were inflicted by gamma ray irradiation from a (60)Co source and thermal radiation from a 5 kW bromotungsten lamp.</p><p><b>RESULTS</b>The dysfunction of myocardium played an important role in the development of early stage shock. Transfusion of irradiated (in vitro, 20 Gy) or stored (4 degrees C, 7 days) blood after irradiation was done to promote the success of allo-transplantation of bone marrow. Decrease of IL-4 mRNA expression was the molecular basis of depression of intestinal mucosa immune and intervention of IL-4 showed an antagonistic effect on enterogenic infection. A new lipid component extracted from burn eschar was documented for the first time and its toxic effects were elucidated. The survival rate of alloskin grafts after removal of burn eschar from the recipient animals was obviously increased in combined injury due to reduction of immune rejection activity by the radiation effect. In contrast, in animal models with simple burn, the alloskin grafts were all rejected within ten days after the procedure. A successful therapeutic result (survival rate: 92% for 30 days and 67% for 100 days) was obtained by comprehensive management of treated animals, while the untreated control animals all died within 3 - 7 days after injury.</p><p><b>CONCLUSION</b>The pathogenesis of injury caused by simultaneous radiation and burn is extremely complicated and the treatment is very difficult. A comprehensive management program consisting of several therapeutic measures aimed at key links of the pathogenesis may achieve significantly improved results.</p>
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Animaux , Souris , Rats , Brûlures , Anatomopathologie , Thérapeutique , Calcium , Métabolisme , Coeur , Hématopoïèse , Lésions radiques , Anatomopathologie , Thérapeutique , Rat WistarRÉSUMÉ
Objective To explore the feasibility of mobilization circulating MSCs by G-CSF and observe the repairing effect of G-CSF mobilization in severe mouse traumatic brain injury(TBI) model.Methods MSCs-derived bone marrow and peripheral blood(PB) were cultured and its CFU-F were counted after mobilization by G-CSF.At 2,24,48,96,120,144,192,264,336 h after severe TBI in mice was establish,the neurobehavior of mice was measured by neurological examination and motor functional test,and mortality rate and pathologic changes were analyzed.Results MSCs-derived PB were successfully cultured.The CFU-F of mobilization group increased significantly than that of control group(P
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Objective To compare the irradiation-protective and inter-synergestic effects of E838,WR-2721, Rubia cordifolia, cystamin e hydrochloride and ethinyl estradiol on radiation and combined radiation-burn injury. Methods Above-mentioned drugs were given to the mice i ntraperitoneally, or intragastrcally, then, the mortality and the average surviv al d for 30 d were observed before and after the administration of the drug s. Results ①When drugs were before injury , the survival rate and the average survival d of the radiation and combined radiation-burn injured mice were increased obviously with the best effect in E838 and WR-2721. ②When drugs were given after injury, E838 and R. cordifolia also kept the effect. ③Combined appling WR-2721（pre) and E838（post）displayed a significant syner gistic reaction. Conclusion E838 and WR-2721 are more e ffective than the others in the prevention of radiation.
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Objective To observe the repair effect of human ?-defensin 2 (hBD 2)-modified rat dermal multipotent stem cells (dMSCs) transplantation on infected wound. Methods Thirty Wistar rats were excised a piece of whole-layer back skin, 3 mm in diameter, then infected the wound with 1?10 8/ml pseudomonas aeruginosa 1 ml, then the rats were injected on the wounded back respectively with dMSCs modified by hBD 2 (n=10), or pure dMSCs (n=10) or none as control (n=10). The repair effect was evaluated by observing the amount of bacteria under the scar, wound healing time and the percentage of remaining wound area. Results The amount of bacteria under the scar in rats that were transplanted with dMSCs modified by hBD 2 was less than that in rats transplanted with dMSCs or controls (P
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Objective To explore the activation of PI3k/Akt pathway of serum deprived IEC-6 cells by the serum of rats exposed to single radiation,burn or combined injury.Methods The IEC-6 cells were cultured in serum deprived media for 24 h,and stimulated by the serum of rats exposed to single radiation(~(60)Co ? ray at dose of 9 Gy),single burn(exposure to 5 kW tungsten-halogen light till whole body Ⅲ degree burn) or combined injury(burn first and radiation),and the cells stimulated by the serum from the normal rats and serum starved cells served as the control group.The total proteins of different group cells were extracted and the levels of phosphorylation of Akt were tested by Western blotting.The differentially expressed low mass proteins in the serums were detected by SELDI proteinchip technology,and primarily analyzed by related software as well as bioinformatic methods.Results The level of phosphorylation of Akt in the IEC-6 cells stimulated by serum from rats exposed to single radiation,single burn or combined injury was higher than in the cells stimulated by the serum from normal rats,in which the burn serum caused the highest level.As compared to burn rat serum,the serum of radiation and combined injury had 13 and 6 differentially expressed protein peaks respectively.Conclusion All the serums from rats exposed to different kinds of damage agents could activate the PI3K/Akt pathway of IEC-6 cells efficiently.The special components of burnt rat serum may contribute to the highest effect on the phosphorylation of Akt.
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Rats were subjected to 15% body surface area third degree burns combined with 2 , 4 , 6 , and 8 Gy irradiation respectively. 48 hours after injury, the DNA and RNA contents of the bone marrow, lymph nodes, spleen and peripheral blood were found to have marked reduction, which became more marked when the dosage of the radiation was increased. Furthermore, it was found that the DNA content decreased more rapidly than the RNA content and the chnage of RNA was more marked in the hemopoietic tissues than in the peripheral blood. Nucleic acid reduction occurred more severely following 2 Gy irradiation than following 15% BSA third degree burns. After the combined iujury of 8 Gy irradiation and burns, th? reduction of nucleic acids in all the above-mentioned tissues exceeded 50%.The mechanism of the changes of necleic acids in the hemopoietic tissues after combined injury of radiation and burns was discussed. Radiation played a more important role than burns in resulting in the reduction but the synergistic effect of burns could not be neglected and could be clearly demonstrated.