Establishment and identification of C57BL/6 mouse model with radiation-induced pulmonary fibrosis / 中华放射肿瘤学杂志

Objective:To establish the mouse model with radiation-induced pulmonary fibrosis, and to identify and analyze it from the aspects of function, imaging and pathology.Methods:Thirty C57BL/6 mice were randomly divided into the control group, 16 Gy irradiation group and 20Gy irradiation group. The mice in the irradiation groups received a single 16 Gy or 20 Gy chest X-ray irradiation, and underwent functional examination, imaging examination and pathological examination at 3 and 6 months after irradiation.Results:At 6 months after irradiation, hair on the chest and back of the mice turned white and fell off, and the airway resistance was increased significantly. CT images showed extensive patch shadows and consolidation in the lung. Three dimensional reconstruction suggested that the lung of mice was distorted and deformed, and the volume was decreased significantly. Pathological examination confirmed that there was extensive pulmonary fibrosis.Conclusions:Significant pulmonary fibrosis occurs after 6 months of chest irradiation in mice. The animal model of radiation-induced pulmonary fibrosis in C57BL/6 mice was successfully established.

Active surveillance and response evaluation strategy after neoadjuvant therapy for esophageal cancer / 中华放射肿瘤学杂志

A considerable proportion of esophageal carcinoma patients could achieve pathological complete response (pCR) after neoadjuvant therapy, for whom accurate response evaluation and active surveillance rather than surgery-aiming to avoid the complications, mortality and reduced quality of life after surgery-has become a research hotspot. To detect residual disease and predict pCR accurately by appropriate method(s) is the key of active surveillance strategy. In this article, we elaborated the active surveillance strategy of esophageal cancer and characteristics of different evaluation methods in terms of radiology, pathology and combined detection.

A study on establishment of examination criteria for the clinical practice of dental students in the department of prosthodontics by Delphi method / 中华医学教育探索杂志

Objective To establish the examination criteria for the prosthodontic clinical practice using Delphi method,to improve the evaluation level of clinical practice of dental students.Method 15 clinical experts in the department of prosthodontics,Peking University School of Stomatology were selected in this study.The evaluation indicators system of prosthodontic clinical practice was established by two rounds of investigations by Delphi method.Initiative ratio and authority coefficient (Cr) of the experts were used to evaluate the reliability of the new examination criteria.Next,the eight-year program students in class of 2007 (38 students) and 2008 (34 students) were examined by old and new examination criteria respectively and the feedback of the students were collected by the method of questionnaire.SPSS 16.0 was used for data processing.Results In this study,the initiative and the authority of the experts was very high,and the initiative ratio and authority coefficient were 100％ and 0.860 respectively.A new examination criterion of prosthodontic clinical practice was established,including 3 first-level indicators,9 second-level indicators and 19 third-level indicators.Questionnaire analysis revealed that only 12％ (n=4) and 9％ (n=3)of the students in class of 2008 considered the new examination criteria was not comprehensive enough or objective enough,which was obviously less than the students in class of 2007 [45％ (n=17) and 36％ (n=14)].Conclusion A new examination criterion of prosthodontic clinical practice was successfully established by Delphi method.The new examination criterion is more comprehensive and objective than the old one and can promote the educational quality of clinical practice of dental students.The method of this study also provides reference for the educational reform of clinical practice in other fields.

A novel tissue-engineered bone constructed by using human adipose-derived stem cells and biomimetic calcium phosphate scaffold coprecipitated with bone morphogenetic protein-2 / 北京大学学报(医学版)

Objective:To construct a novel biomimetic calcium phosphate (BioCaP) scaffold loaded with bone morphogenetic protein-2 (BMP-2),and to investigate its role in the osteogenesis of human adipose-derived stem cells (hASCs) in vitro and in vivo.Methods:The BioCaP scaffold coprecipitated with BMP-2 (BMP-2-BioCaP) was constructed in this study.Field emission scanning electron microscopy (SEM) was used to analyze the morphology of the surfaces.The release kinetics was measured to evaluate the slow-release characteristics in vitro.BMP-2-BioCaP was immersed in proliferation medium (PM) or osteogenic medium (OM),respectively.The supernatants were collected and used to culture hASCs in vitro.Cell numbers were determined using the cell-counting kit-8 (CCK-8) to assess the cell proliferation.After 7 and 14 days,alkaline phosphatase (ALP) staining and quantification were performed to test the activity of ALP.After 14 and 21 days,the calcification deposition was determined by alizarin red S (ARS) staining and quantification.The expressions of the osteoblast-related genes were tested on day 4 and day 14.In the in vivo study,6 nude mice were used and implanted subcutaneously into the back of the nude mice for 4 groups:(1) BioCaP scaffold only,(2) BioCaP scaffold + hASCs,(3) BMP-2-BioCaP scaffold,(4) BMP-2-BioCaP scaffold + hASCs (test group).After 4 weeks of implantation,hematoxylin-eosin (HE) staining was performed to evaluate the in vivo osteogenesis of hASCs.Results:SEM observations showed that BioCaP and BMP-2-BioCaP scaffold were entirely composed of straight,plate-like and sharp-edged crystal units,and the length of the crystal units varied between 5 and 10 μm.Release kinetics analysis demonstrated that BMP-2 incorporated with BioCaP could be released at certain concentration and last for more than 21 days,and the accumulative protein release could reach 20％.CCK-8 assays showed that cell proliferation was not significantly affected by BMP-2BioCaP.ALP activity was higher by the induction of OM + BMP-2-BioCaP than of the other groups (P ＜0.01).More mineralization deposition and more expressions of osteoblast-related genes such as Runt-related transcription factor 2 (RUNX2),ALP,osteopontin (OPN) and osteocalcin (OC) were determined in the OM + BMP-2-BioCaP group at different time points (P ＜0.01).HE staining showed that,in the test group and BMP-2-BioCaP scaffold group,the extracellular matrix (ECM) with eosinophilic staining were observed around hASCs,and newly-formed bone-like tissues could be found in ECM around the scaffold materials.Moreover,compared with the BMP-2-BioCaP scaffold group,more bone-like tissues could be observed in ECM with typical structure of bone tissue in the test groups.No obvious positive results were found in the other groups.Conclusion:BMP-2-BioCaP scaffold could achieve slow-release of BMP-2 and promote the osteogenic differentiation of hASCs in vitro and in vivo.The novel tissue-engineered bone composed of hASCs and BMP-2-BioCaPis promising for the repair of bone defect.

Diagnossis and treatment of complicated anterior teeth esthetic defects by combination of whole-process digital esthetic rehabilitation with periodontic surgery / 北京大学学报(医学版)

Objective:To explore a new method of whole-process digital esthetic prosthodontic rehabilitation combined with periodontic surgery for complicated anterior teeth esthetic defects accompanied by soft tissue morphology,to provide an alternative choice for solving this problem under the guidance of three-dimensional (3 D) printing digital dental model and surgical guide,thus completing periodontic surgery and digital esthetic rehabilitation of anterior teeth.Methods:In this study,12 patients with complicated esthetic problems accompanied by soft tissue morphology in their anterior teeth were included.The dentition and facial images were obtained by intra-oral scanning and three-dimensional (3D) facial scanning and then calibrated.Two esthetic designs and prosthodontic outcome predictions were created by computer aided design/computer aided manufacturing (CAD/CAM) software combined with digital photography,including consideration of white esthetics and comprehensive consideration of pink-white esthetics.The predictive design of prostheses and the facial appearances of the two designs were evaluated by the patients.If the patients chose the design of comprehensive consideration of pink-white esthetics,they would choose whether they would receive periodontic surgery before esthetic rehabilitation.The dentition design cast of those who chose periodontic surgery would be 3D printed for the guide of periodontic surgery accordingly.Results:In light of the two digital designs based on intra-oral scanning,facing scanning and digital photography,the satisfaction rate of the patients was significantly higher for the comprehensive consideration of pink-white esthetic design (P ＜ 0.05) and more patients tended to choose priodontic surgery before esthetic rehabilitation.The 3 D printed digital dental model and surgical guide provided significant instructions for periodontic surgery,and achieved success transfer from digital design to clinical application.The prostheses were fabricated by CAD/CAM,thus realizing the whole-process digital esthetic rehabilitation.Conclusion:The new method for esthetic rehabilitation of complicated anterior teeth esthetic defects accompanied by soft tissue morphology,including patient-involved digital esthetic analysis,design,esthetic outcome prediction,3D printing surgical guide for periodontic surgery and digital fabrication is a practical technology.This method is useful for improvement of clinical communication efficiency between doctor-patient,doctor-technician and doctors from different departments,and is conducive to multidisciplinary treatment of this complicated anterior teeth esthetic problem.

The role of oxidative stress in the acute liver injury of rats with heat stroke and its mechanism / 解放军医学杂志

Objective To investigate the role of oxidative stress in acute liver injury in a heat stroke model of conscious rats,and to explore its underlying mechanism.Methods Thirty-two rats were randomly (by using a random number table) assigned into a sham-heated control group (Sham group,n=8),a sham-heated group treated with NAC (Sham-NAC group,n=8),a heat stroke group (HS group,n=8) and a heat stoke group treated with NAC (HS-NAC,n=8).Rats were prepared with pre-warm chamber to initiate heat stoke.The change of rectum temperature (Tr),heart rate (HR) and systolic blood pressure (SBP) were monitored,and the time point of HS onset was recorded.Rats were sacrificed 12h after HS onset.ALT,serum TBIL,IL-6,IL-1β,TNF-α,MDA,T-SOD and GSH in the liver homogenates were measured.Liver tissues were harvested for determining the concentration of reactive oxygen species (ROS),neutrophil infiltration and the histological changes.Results During HS onset,no significant differences were observed in Tr,HR,SBP and heat exposure time between HS group and HS-NAC group (P＞0.05).However,the survival time was significantly longer in HS-NAC group than in HS group (P=0.039).12 hours after HS onset,the concentrations of ROS and MDA in the liver homogenates were significantly higher in HS group than in the other groups (P=0.000),while the concentrations of T-SOD and GSH were much lower than in the other groups (P=0.000).The serum concentrations of ALT and TBIL were significantly higher in HS group than in the other groups (P=0.000).Compare with HS group,the pathological injury was alleviated in HS-NAC group (P=0.000).The neutrophil infiltration level and the concentrations of IL-6,IL-1 β and TNF-α in liver tissue were significantly higher in HS group than in HS-NAC group (P=0.000).Conclusion Oxidative stress may play an important role in the pathogenesis of HS liver injury through its cytotoxic effect and by inducing inflammatory responses.

Protective effects of heat shock protein 70 on the acute lung injury of rats with heat stroke and its mechanism / 解放军医学杂志

Objective To investigate the protective effect of heat shock protein (HSP) 70 on the acute lung injury (ALI) of rats with heat stroke.Methods Sixty four rats were randomly (by employing a random number table) assigned into a sham-heated group (Sham group),heat stress group (HS group),and HS plus gluttamine treatment group (HS+GLN group) and HS plus quercet in treatment group (HS+QU group),16 each.All rats were housed in a artificial climate chamber,with the rats in the sham groups exposed to a temperature of 23 ℃ and humidity of 55％ ± 5％,while the rats of HS,HS+GLN and HS+QU groups to an ambient temperature of 39 ℃ and humidity of 65％.During heat stress or sham heating,rectal temperature (Tr),systolic blood pressure (SBP) and pulse rate (PR) were monitored to observe the difference in heat stress response among the groups.The time point at which the SBP started to drop from the peak level was taken as the point of HS onset.At the onset of HS,heat exposure was terminated,then the rats were immediately removed from the chamber,and returned to room temperature.The rats were scarified 0h and 6h after HS onset respectively.After bronchoalveolar lavage fluid (BALF) was collected,the lungs of all animals were harvested for pathological examination of lung injury.The concentrations of IL-1β,TNF-α and IL-6 in BALF and HSP70 in lung homogenate were measured by using an enzyme linked immunosorbent assay kit.Results Compared with HS and HS+QU groups,the rats in HS+GLN group required significantly greater heat load to induce HS (P＜0.001),and had longer survival time span after HS onset.Compared with Sham group,the concentration of HSP70 in lung homogenate in HS group increased in a time-dependent manner (P＜0.001).In comparison with HS group,the concentration of HSP70 in lung homogenate from HS+GLN group was significantly elevated at each time point (P＜0.001),while the treatment with QU significantly inhibited the expression of HSP70 (P＜0.001).The concentration of IL-1β,TNF-α and IL-6 in BALF significantly decreased in HS+GLN group compared with those in HS group and HS+QU group (P＜0.001).The pathological results showed that the lung injury was milder in HS+GLN group,while the opposite in HS+QU group.Conclusion HSP70 could protect HS rats against ALI by enhancing their thermo-tolerance and inhibiting inflammatory response.

Anesthetic Effect and Safety of General Anesthesia and Combined Spinal and Epidural Anesthesia used in Autonomic Nervous Hyperresponsive Surgery for Patients with Paraplegia / 昆明医科大学学报

Objective To compare anesthetic effect and safety of general anesthesia and combined spinal and epidural anesthesia used in autonomic nervous hyperresponsive surgery for patients with paraplegia.Methods 26 paraplegic patients were randomly divided into two groups-control group and treatment group from February 2011 to November,2015,each with 13 cases.The control group used general anesthesia,while the treatment group used combined spinal and epidural anesthesia,to observe onset time,duration,intraoperative hemodynamic changes and complications,Complications,length of stay and cost,Days and costs of hospitalization,satisfaction of patients and their families,of anesthesia in two groups.Results The dosage of narcotics and the onset time of the treatment group were better than that of the control group.The difference between the two groups was significant,and had statistical significance (P＜0.05) Two groups of patients after surgery,diastolic blood pressure,systolic blood pressure and heart rate were lower in the treatment group than in the control group,and had statistically significant difference (P＜0.05);The postoperative complications of the treatment group were significantly better than those of the control group,and had statistically significant difference (P＜0.05);There were statistically significant differences in postoperative pain degree between the two groups (P＜0.05);Two groups of patients in hospital days,hospital costs,satisfaction rate had statistically significant difference,Have statistical significance (P＜0.05).Conclusion In autonomic nervous hyperresponsive surgery for patients with paraplegia,anesthetic effect and safety of combined spinal and epidural anesthesia is significantly better than that of general anesthesia,featured by the rapid onset of action,long duration,fewer complications,strong safety and patients' great satisfaction.It is worth generalizing and applying clinically.

Constructing 3-dimensional colorized digital dental model assisted by digital photogra-phy / 北京大学学报(医学版)

Objective:To explore a method of constructing universal 3-dimensional (3D)colorized digital dental model which can be displayed and edited in common 3 D software (such as Geomagic se-ries),in order to improve the visual effect of digital dental model in 3D software.Methods:The mor-phological data of teeth and gingivae were obtained by intra-oral scanning system (3Shape TRIOS),con-structing 3D digital dental models.The 3D digital dental models were exported as STL files.Meanwhile, referring to the accredited photography guide of American Academy of Cosmetic Dentistry (AACD),five selected digital photographs of patients’teeth and gingivae were taken by digital single lens reflex camera (DSLR) with the same exposure parameters (except occlusal views ) to capture the color data.In Geomagic Studio 201 3,after STL file of 3D digital dental model being imported,digital photographs were projected on 3D digital dental model with corresponding position and angle.The junctions of different photos were carefully trimmed to get continuous and natural color transitions.Then the 3 D colorized digital dental model was constructed,which was exported as OBJ file or WRP file which was a special file for software of Geomagic series.For the purpose of evaluating the visual effect of the 3 D colorized digital model,a rating scale on color simulation effect in views of patients’evaluation was used.Sixteen patients were recruited and their scores on colored and non-colored digital dental models were recorded.The data were analyzed using McNemar-Bowker test in SPSS 20.Results:Universal 3D colorized digital dental model with better color simulation was constructed based on intra-oral scanning and digital photography. For clinical application,the 3D colorized digital dental models,combined with 3D face images,were in-troduced into 3D smile design of aesthetic rehabilitation,which could improve the patients’cognition for the esthetic digital design and virtual prosthetic effect.Conclusion:Universal 3 D colorized digital dental model with better color simulation can be constructed assisted by 3 D dental scanning system and digital photography.In clinical practice,the communication between dentist and patients could be improved as-sisted by the better visual perception since the colorized 3 D digital dental models with better color simula-tion effect.

Promoted role of bone morphogenetic protein 2/7 heterodimer in the osteogenic differentiation of human adipose-derived stem cells / 北京大学学报(医学版)

Objective:To investigate the role of bone morphogenetic protein 2/7 heterodimer (BMP-2/7)in the osteogenesis of human adipose-derived stem cells (hASCs).Methods:hASCs were exposed to three different treatments in vitro:osteogenic medium with 1 50 μg/L BMP-2/7 (experimental group), osteogenic medium alone (OM group)and proliferation medium (PM group).After 1 ,4 and 7 days of osteogenic induction,the amount of cellular DNA was measured to investigate the cytotoxicity.After 7 and 1 4 days,alkaline phosphatase (ALP)staining and quantification were performed to test the activity of ALP.After 21 and 28 days,the calcification deposition was determined by Alizarin Red S (ARS)stai-ning and quantification.The expressions of the osteoblast-related genes were tested on days 1 ,4,7 and 1 4.In the in vivo study,6 nude mice were used and 4 groups were set and implanted subcutaneously into the back of nude mice:(1 )β-TCP scaffold only (scaffold control group );(2 )β-TCP scaffold with hASCs cultured by PMin vitro for 1 week (PMcontrol group);(3)β-TCP scaffold with hASCs cultured by OM in vitro for 1 week (OM control group);(4)β-TCP scaffold with hASCs cultured by OM with 1 50 μg/L BMP-2/7 in vitro for 1 week (test group).After 4 weeks of implantation,histological staining was performed to evaluate the in vivo osteogenesis of hASCs.Results:After induction for 1 day,there was no significant difference between the experimental group and the PM group on the cellular DNA con-tent (P>0.05 ).After 4 days,the cellular DNA content increased under the stimulation of BMP-2/7 (P0.05).ALP ac-tivity was higher by the induction of BMP-2/7 than in OMalone and PM(P<0.05).More mineraliza-tion deposition and more expressions of osteoblast-related genes such as Runx2,ALP,COL-1 A1 and OC were determined in the experimental group at different time points (P<0.05).HE staining showed that, in the test group and OM control group,the extracellular matrix (ECM)with eosinophilic staining were observed around hASCs,and newly-formed bone-like tissues could be found in ECM around the scaffold materials.Moreover,compared with the OM control group,more bone-like tissues could be observed in ECMwith typical structure of bone tissue in the test group.Masson’s trichrome staining showed that more expression of collagen could be observed in ECM in the test group compared with the other groups.There was small amount of expression of collagen in the OM and PM control groups.No obvious positive results were found in the scaffold group.Conclusion:BMP-2/7 heterodimer plays a significant role in the osteo-genesis of hASCs and is able to enhance the osteogenic differentiation of hASCs in vitro and in vivo.

Establishing a luciferase reporter system to evaluate osteogenic differentiation poten-tial of human adipose-derived stem cells / 北京大学学报(医学版)

Objective:Human adipose-derived stem cells (hASCs)are a highly attractive source in bone tissue engineering.To generate a luciferase reporter system that could be used to quantitatively and rapidly examine osteogenic differentiation potential of human adipose-derived stem cells (hASCs ) in vitro,and eventually make it possible to monitor the osteogenic differentiation of transplanted cells in vi-vo.Methods:The genomic DNA harboring promotor regions of osteocalcin and DNA sequences encoding luciferase genes were amplified by PCR and cloned into the pLVX-pTRE-puro vector to generate the OCpro-Luc-Puro construct.Then,the OCpro-Luc-Puro construct together with three assistant vectors:pM-DLg/pRRE,pRSV-REV,and pVSVG,were transiently transfected into HEK293T cells followed by viral supernatants collection,filtration and concentration.Next,the hASCs stably expressing luciferase repor-ter gene driven by osteocalcin promotor were created with the lentivirus carrying OCpro-Luc-Puro cassette under puromycin selection.The OCpro-Luc-hASCs were then cultured in the absence or presence of osteo-genic differentiation medium.On the 7th and 1 4th days,after osteogenic induction,cellular extracts were collected and analyzed by luciferase reporter assay.Meanwhile,alizarin red staining and quantification as well as quantitative reverse transcription PCR (qRT-PCR)analysis of osteogenic associated genes osteo-calcin (OC),runt-related transcription factor 2 (Runx2)and alkaline phosphatase (ALP)were used to assess the osteogenic differentiation ability of OCpro-Luc-hASCs.Results:OCpro-Luc-Puro plasmid and OCpro-Luc-hASCs were successfully generated.On the 7th and 1 4th days after osteogenic induction,the luciferase activity of the cellular extracts from OCpro-Luc-hASCs was dramatically increased.Consistently, the extracellular matrix mineralization,as shown by Alizarin red S (ARS)staining and quantification was also markedly intensified and a marked increase of the mRNA expression levels of OC,Runx2 and ALP, although to variable extent,was observed upon osteogenic differentiation.These results indicated that the observations from traditional experiments examining hASCs osteogenic differentiation were largely in agreement with that of our luciferase reporter assay in OCpro-Luc-hASCs.Conclusion:We established a luciferase reporter system that could be used to rapidly,quantitatively and specifically determine osteo-genic differentiation ability of hASCs.Comparing with the traditional time-consuming methods,the system we generated here was highly effective.This system not only can be used to examine ostogenic differentia-tion of hASCs in a high throughput manner,but also provides a way to monitor ostogenic differentiation of cells in vivo.

Different multidisciplinary approaches of two traumatic teeth fractures in the esthetic zone:a case report / 北京大学学报(医学版)

SUMMARY In this article , different methods to deal with teeth fractures were discussed by presenting a case of traumatic crown-root fracture in the anterior esthetic zone .The traumatic crown-root fracture is a common problem in clinic .When a fracture line locates in close proximity to or below the alveolar bone crest , the fracture most likely involve the junctional epithelium and the connective tissue attachment .This type of fracture becomes a challenge for restorative dentists because it involves biologic , functional , and es-thetic considerations , especially when the fracture occurs in an esthetic area .In this case , a young patient presented with two fractured upper anterior teeth to the Department of Periodontics , Peking University School and Hospital of Stomatology .After the comprehensive clinical evaluation , the right central incisor was decided to extract for implant therapy and the right lateral incisor was decided to retain by one modified crown lengthening surgery .The most common technique applied to save a retained root is a clinical crown lengthening procedure .However , the aggressive alveolar bone resection of both target and adjacent teeth to reestablish the bone width and periodontal health may compromise functional and esthetic outcomes .To re-duce loss of excessive osseous tissue during osteotomy procedure , the modified crown lengthening of the right lateral incisor was performed , including minor bone resection and root reshaping .Regarding the right central incisor , the retained root was all located below the alveolar bone crest .The extraction and implant procedure , combined with guided bone graft were performed to avoid the damage to neighbor teeth during traditional restorative therapy and to reshape a preferable buccal contour .At the last visit , the patient was recalled with healthy periodontium , normal tooth function and favorable esthetic results .

Correlation of kidney injury and inflammatory response in rats with classic severe heatstroke / 中华危重病急救医学

ObjectiveTo investigate the temporal features of renal injury in rats with severe heat stroke (SHS) and their relationship with inflammatory response.Methods Fifty-six male Wistar rats were randomly divided into normal control group and SHS for 0, 2, 6, 24, 48, 72 hours group (SHS-0, 2, 6, 24, 48, 72 h groups), with 8 rats in each group. Rats were placed in an artificial climate chamber [temperature (39.5±0.2)℃, humidity (60±5)%] to induce SHS model, and the criterion for successful model reproduction was the onset of lowering peak systolic blood pressure (SBP). Then the rats were transferred to room temperature (23.0±0.2)℃ after successful reproduction of the model. The rats of normal control group were kept in room temperature of (23.0±0.2)℃. Heart blood and renal tissue samples were harvested, and the levels of serum creatinine (SCr) and blood urea nitrogen (BUN) were determined by automatic biochemistry analyzer. The levels of myeloperoxidase (MPO), tumor necrosis factor-α(TNF-α) and interleukin-6 (IL-6) in renal tissue specimens were determined by enzyme linked immunosorbent assay (ELISA). The changes in histopathology in kidney were observed with light microscopy, and Paller scores were used to assess the degree of renal injury.Results Compared with normal control group, the levels of SCr and BUN in serum, and MPO, TNF-α and IL-6 in the renal tissue homogenate were significantly increased in SHS-6 h group [SCr (μmol/L): 174.0±27.0 vs.68.0±11.3, BUN (mmol/L): 12.6±2.3 vs. 4.3±1.2, MPO: (203.0±38.0)% vs. (100.0±1.4)%, TNF-α: (121.0±16.0)% vs. (100.0±1.4)%, IL-6: (118.0±19.0)% vs. (100.0±1.3)%, allP< 0.05], and they peaked at 24 hours [SCr (μmol/L): 489.0±96.0 vs. 68.0±11.3, BUN (mmol/L): 19.3±5.7 vs. 4.3±1.2, MPO: (511.0±41.0)% vs. (100.0± 1.4)%, TNF-α: (399.0±47.0)% vs. (100.0±1.4)%, IL-6: (473.0±56.0)% vs. (100.0±1.3)%, allP< 0.01], then declined to the normal levels at 72 hours. Under light microscopy, tissue edema and necrosis of renal tubules were found, and leukocyte infiltration was found to be most profuse at 24 hours, then they returned to normal levels at 72 hours. Paller scores in SHS-6 h group were significantly higher than those of the normal control group (75.45±9.70 vs. 14.23±3.26,P< 0.01), and it peaked at 24 hours (186.00±14.25 vs. 14.23±3.26,P< 0.01), followed by a gradual lowering, back to normal level at 72 hours.ConclusionThe results suggest that progressive renal damage occurred in the rats with SHS within 24 hours, and it was accompanied with elevated levels of MPO, TNF-α and IL-6 in the kidney homogenate, suggesting that inhibition of neutrophil activation and the release of IL-6, TNF-α may protect the SHS associated renal injury.

Ectopic osteogenesis of stromal cell-derived factor 1 combined with simvastatin-loaded collagen scaffold in vivo / 北京大学学报(医学版)

Objective:To construct and evaluate a novel tissue-engineered bone composed of murine stromal cell-derived factor 1(mSDF-1), simvastatin (SIM) and collagen scaffold (Bio-Oss?), serving as a cell-homing approach for bone formation .Methods: In the study , 32 ICR mice were randomly divided into 4 groups,each group including 8 mice.The drug-loaded collagen scaffolds were implanted subcutaneously onto the cranium of each mouse according to the groups: ( 1 ) 1 ∶50 ( volume ratio ) dimethyl sulfoxide ( DMSO ) /phosphate-buffered saline ( PBS ) solution +collagen scaffold ( blank control group ); ( 2 ) 10 -3 mol/L SIM solution +collagen scaffold ( SIM group ); ( 3 ) 200 mg/L mSDF-1solution +collagen scaffold (mSDF-1 group); and (4) 10 -3mol/L SIM +200 mg/L mSDF-1 solution +collagen scaffold ( SIM +mSDF-1 group) .One week after implantation , the mice were trea-ted by injecting the same drug solution mentioned above around the scaffold once a day for two days .The specimens were harvested 6 weeks after implantation and the bone formation was evaluated by soft X-ray analysis , HE staining and immunohistochemical staining .Angiogenesis of each group was checked by calculation of vessels in each tissue section .Results:Six weeks after implantation , the collagen scaffolds were retrieved.The value of gray scale for the SIM +mSDF-1 group[(421 836.5 ±65 425.7) pixels] was significantly higher than that of the blank control group [(153 345.6 ±45 222.2)pixels, P<0.01], the SIM group [(158 119.2 ±100 284.2) pixels, P<0.01], and the mSDF-1 group[(255 529.5 ± 152 142.4) pixels, P <0.05 ]; HE staining analysis revealed that significant bone formation was achieved in the SIM +mSDF-1 group; The immunohistochemical staining showed the existence of os-teopontin and osteocalcin in the SIM +mSDF-1 group; There were more vessels in the SIM +mSDF-1 group[(46 ±8)vessels/mm2] than in the blank control group [(23 ±7) vessels/mm2, P<0.01], and the SIM group[(24 ±6) vessels/mm2 , P<0.01].Conclusion:The novel tissue-engineered bone com-posed of mSDF-1, SIM and collagen scaffolds has the potential to form bone subcutaneously in vivo.It re-presents a novel method of in vivo bone re-generation without seed cell delivery .

Activation of nuclear factor kappa B during heat stress-induced neuronal apoptosis / 中国组织工程研究

BACKGROUND:Hyperpyrexia can induce a wide range of cel apoptosis in organisms, but no study has introduced the mechanism of heat stress-induced neuronal apoptosis. OBJECTIVE:To observe the effect of nuclear factor kappa B (NF-κB) signal pathway on heat stress-induced neuronal apoptosis through reactive oxygen species. METHODS:Heat stress model was established in the cel incubator. Heat stress group of cel s were incubated at 39,41,43℃for2hours,whilecontrolgroupofcelswereincubatedat37 ℃in5% CO2 for 2 hours. Apoptosis was analyzed by flow cytometry using Annexin V-FITC/PI staining. The expression levels of caspase-3 and p-NF-κB65 were determined by western blot analysis. The amounts of intracel ular reactive oxygen species were assayed by DCFH staining. In addition, the effect of MnTMPyP and PTDC on heat stress-induced apoptosis was also studied. RESULTS AND CONCLUSION:39 ℃ heat stress had no impact on the apoptosis, 41 ℃ heat stress induced a smal amount of apoptosis (10.19%), and 43 ℃ heat stress triggered a large amount of apoptosis (43.02%). The expression of caspase-3 and p-NF-κB65 was increased, in a temperature-dependent manner. In addition, both MnTMPyP and PTDC significantly decreased the heat stress-induced apoptosis and expression of caspase-3 and p-NF-κB65. Experimental findings indicate that, the increase of intracel ular reactive oxygen species may induce neuronal apoptosis, and NF-κB participates in the heat stress-induced neuronal apoptosis as the intermedial signal pathway.

The effect of reactive oxygen species on heat stress-induced neuronal apoptosis / 中华急诊医学杂志

Objective To observe the effect of heat stress-induced burst out of reactive oxygen on neuronal apoptosis and investigate pathogenesis of brain damage caused by severe heat stroke.Methods Neurons heat stress model is set up.Control group were incubated at 37 ℃,5%CO2 ,While heat stress group of cells were incubated at 43 ℃for 2 h,then all the cells were further incubated at 37 ℃for different time as indicated.The amounts of ROS were assayed by DCFH staining at 0 h,0.5 h,1 h,2 h after heat stress.Apoptosis was analyzed by flow cytometry using Annexin V-FITC/PI staining and expression of caspase-3 were determined by westen blotat 0 h、3 h、6 h、12 h after heat stress.In addition,MnTMPyP is the specificscavengers of ROS,which effect on apoptosis is also studied at 12 h after heat stress.Results Compared with control group,amounts of ROS was significant increased at 0 h after heat stress,the burst out of it was at 2 h after heat stress (P<0.05 ).Apoptosis was induced at 3h after heat stress ,it was significant increased at 12 h after heat stress (43.2%,P<0.05 ).The expression of caspase-3 was also significant increased at 12 h after heat stress (P<0.05 ),and its trend was consistent with apoptosis rate trend.In addition,the scavengers MnTMPyP significantly decreased the apoptosis (47.42% to 18.45%, P<0.05 )and expression of caspase-3 at 12 h after heat stress.Conclusions An upstream signaling molecules,ROS could mediate heat stress-induced neuronal apoptosis,but its intermediate mechanism needs for further studies.

Diagnostic significance of cardiac troponin Ⅰ in multiple trauma patients combined with myocardial contusion / 中华创伤杂志

Objective To investigate the value of cardiac troponin Ⅰ (cTn Ⅰ) in diagnosis of multi-trauma patients combined with myocardiac contusion.Methods A retrospective review was made on 98 cases of multi-trauma patients combined with blunt chest trauma.The groups were identified according to whether the patients were associated with myocardiac contusion or not,including myocardiac contusion group (n =48) and non-myocardiac contusion group (n =50).The detection and diagnosis of myocardiac contusion in the use of different cut-off points of cTn Ⅰ and creatine kinase MB isoenzyme/creatine kinase (CKMB/CK) or their combination were compared between groups.Results cTn Ⅰ ≥0.60 ng/ml had a specificity of 90.0％,a sensitivity of 64.6％ and a Youden index of 0.54 in diagnosis of myocardiac contusion,indicating a best diagnostic accuracy as a single parameter.As compared with the single use of cTn Ⅰ ≥ 0.60 ng/ml or CKMB/CK ≥ 6％ in diagnosis of myocardiac contusion,the combined use of two parameters presented a significantly higher diagnostic sensitivity (85.4％ vs 64.6％ ; 85.4％ vs 27.1％ respectively,both P ＜ 0.05),but no markedly lower specificity (84.0％ vs 90.0％ ; 84.0％ vs 88.0％ respectively,both P ＞0.05).cTn Ⅰ level was positively correlated with ISS score of the multi-trauma patients combined with myocardiac contusion (r =0.534,P ＜ 0.01).Mortality rate in patients with severely increased cTn Ⅰ was much higher than that in patients with mild-moderately increased cTn Ⅰ (P ＜ 0.01).Conclusions cTn Ⅰ ≥0.60 ng/ml presents a high sensitivity and preferable specificity for diagnosis of multiple trauma patients combined with myocardiac contusion.It can be served as a biomarker for diagnosis of MC and its combination with CKMB/CK≥6％ improves the diagnostic sensitivity.cTn Ⅰ can be used as an assessment indicator for the early risk stratification and outcome in multi-trauma patients combined with myocardiac contusion.

Analysis of epidemiologic characteristics of trauma in 10 654 patients in Guangzhou / 中华急诊医学杂志

Objective To study the epidemiologic characteristics of trauma in the prehospital first-aid in megapolis. Methods The epidemiologic data of 10 654 traumatic patients,including treated by prehospital treatment and emergency treatment from January 2000 to January 2005,were analyzed.Results The proportion of male was 70.96%,adult patients(21～50 years old)79.23%,suburb 62.86%,downtown 37.14%.The patients whose ISS scores surpassed 16 accounted for 37.98%,which caused by traffic accident was 37.74%,by public order 24.39%,by industrial trauma 21.71%.The trauma in the limbs accounted for 67.51%,cephalic and cervical wounds accounted for 58.64%,multiple wounds 41.77%,thoracic and abdominal wounds 39.41%.Three hundred and sixty one were killed on the spot,which caused by traffic accident were 46.81%,by public order 28.81%,by industrial trauma 14.40%.Forty-two percent point six six patients died of multiple trauma,54.07% died of cephalic and cervical trauma,15.79% died of thoracic and abdominal wounds.Conclusion Suburban area gradually became the frequently-occurred areas of trauma in megapolis. The wounded were mainly young adults and had a tendency of juvenility.The majority of damaging and lethal factors were traffic accident,public order and industrial trauma.Some pertinet measures and professional first-aid models may improve the traumatic first-aid level.

ENDOVASCULAR MICROCOIL EMBOLIZATION OF EXPERIMENTAL TRAUMATIC PSEUDOANEURYSM OF COMMON CAROTID ARTERY IN RABBITS / 解放军医学杂志

Traumatic pseudoaneurysms (TPA) were surgically produced in the right common carotid artery of 24 rabbits. Three to four weeks later the survived rabbits 16 were randomly divided into 3 groups: (1)control group; (2)treatment group with TPAs embolized with microcoils(MC); (3)treatment group with occlusion of the by parent artery with MC. Three months after embolizaton, the TPAs were examined by digital subtraction angiography (DSA). The results showed that the TPAs embolized with MC were proved to be completely occluded, and the parent artery remained patent. Histopathological examination showed that TPAs were replaced by a mass of scar tissues. In the rabbits with occlusion of the parent artery embolization with MC, the TPA also disappeared. However, all the untreated rabbits died of rupture of TPAs. Statistic analysis showed that both methods of treatment were effective in the treatment of TPA.