Analysis of Differentially Expressed Proteins Distribution in the Rat Brains with DAI by MALDI-TOF-IMS / 法医学杂志

OBJECTIVES@#To establish the imaging mass spectrometry for analysis of differentially expressed proteins distribution in the rat brains with diffuse axonal injury （DAI） based on matrix assisted laser desorption/ionization-time of flight imaging mass spectrometry （MALDI-TOF-IMS）.@*METHODS@#MALDI-TOF-IMS scanning were conducted on the brains of DAI group and control group in the m/z range of 1 000 to 20 000 using AutoflexⅢ MALDI-TOF spectrometer. ClinProTool 2.2 software was used for statistical analysis on the data of two groups, and then the differentially expressed proteins were picked out to conduct imaging. The distribution of the proteins with different m/z in the rat brains was observed.@*RESULTS@#Five proteins with different m/z, including 4 963, 5 634, 6 253, 6 714 and 7 532, differentially expressed in the rat brains with DAI.@*CONCLUSIONS@#MALDI-TOF-IMS can be used for studying the differentially expressed proteins in rat brains with DAI and the analysis method is established for exploring the distribution of differentially expressed proteins in the rat brains with DAI using imaging mass spectrometry.

Application of diffusion tensor imaging and 1H-magnetic resonance spectroscopy in diagnosis of traumatic brain injury / 法医学杂志

Mild traumatic brain injury (mTBI) is a common type of brain disorders among young adults. The dysfunction of the brain is often exacerbated due to diffuse axonal injury (DAI) which based on the injury of white matter fibers and axons. Since mild and moderate brain injury or DAI are diffuse and subtle, conventional CT and MRI are difficult to make a positive diagnosis. Recent clinical study indicated that functional magnetic resonance imaging has a high detection rate in the diagnosis of acute mild and moderate brain injury, especially the diffusion tensor imaging (DTI) and 1H-magnetic resonance spectroscopy (1H-MRS). This paper has reviewed the principles and characteristics of DTI and 1H-MRS, and recent research in the clinical and animal experiments on brain injury.

Expression of HSP70 mRNA in hippocampus of rats after diffuse axonal injury / 法医学杂志

OBJECTIVE@#To explore the changes of expression of heat-shock proteins (HSP) 70 mRNA in hippocampus of rats after diffuse axonal injury (DAI).@*METHODS@#RT-PCR products of HSP70 mRNA were tested by agarose gel electrophoresis after RT-PCR amplification. The changes of HSP70 mRNA expression were observed in rat hippocampus after DAI.@*RESULTS@#The expression of HSP70 mRNA in the hippocampus could be detected 4 h after DAI. It reached maximum at 24 h and declined after 48 h.@*CONCLUSION@#HSP70 mRNA in hippocampus of rats could be useful for diagnosis of DAI.

Analysis of 112 cases with diffuse axonal injury / 法医学杂志

OBJECTIVE@#To investigate the relationship between the diffuse axonal injury (DAI) and cerebral contusion, primary brain stem injury and brain concussion.@*METHODS@#One hundred and twelve cases with DAI were analyzed according to the characteristics of clinical signs and imaging features.@*RESULTS@#Of 112 cases of DAI, 70.5% injured in traffic accident, 60.7% injured with blunt trauma more than one time and 71.4% injured with cerebral contusion. And 90 cases with brain with hemorrhage were found in CT or MRI imaging.@*CONCLUSION@#DAI may be associated with cortical contusion and primary brain stem injury. The CT or MRI is useful to investigate the cause of death and to evaluate the personal disability.

Expression of synaptophysin in experimental diffuse brain injury / 法医学杂志

OBJECT@#To investigate the changes in the expression_level of synaptophysin following diffuse brain injury (DBI) in rats and to correlate the changes of the synaptophysin expression_level with the post injury time interval.@*METHODS@#Wister rats were used as a DBI model induced by Marmarou method. The changes of synaptophysin immunoreactivity on coronal sections of the rats sampled at different post-injury time intervals were used as a marker. The densitometry of the synaptophysin immunoreactivity was documented by imaging technique and analyzed by SPSS software.@*RESULTS@#The expression level of synaptophysin in DBI rats showed dynamic changes following DBI as well as during the repairing period.@*CONCLUSION@#The changes of synaptophysin level may be used as a marker for estimation of the post injury time interval in DBI.

Expression of beta-amyloid precursor protein in diffuse axonal injury of rats / 法医学杂志

OBJECTIVE@#To explore an method for diffuse axonal injury (DAI) diagnosis and injury time estimation, the changes of beta-APP immunoreactivity and to observe the morphology of axonal in different parts of brain after experimental DAI injury.@*METHODS@#The animal models of DAI was established according to the Marmarou's method. Immunohistochemistry and Gless staining were performed to observe the changes of beta-APP expression and the morphology of axon with the time elapsed after the DAI injury.@*RESULTS@#In the brain injury group, the morphologic changes of axon in brain stem were showed as twisted, broken and swellen at 0.5 h, and the myelin sheaths broken could be observed, the retraction ball was found at 12 h. Those morphology changes further progressed at 12h, reached to peack up to 1 d, then repaired at 3 d, and recovered at 10 d; Meanwhile the analysis of beta-APP immunoreactivity was also showed a time-dependent difference as fellows: beta-APP expression begin at 3h, increased its immunoreactivity at 12h, reached to maximize at 1 d, decreased after 3 d, returned to basal level at 10 d.@*CONCLUSIONS@#The results suggest that beta-APP immunohistochemistry combine with Gless staining be sensitive methods for DAI diagnosis, they could discover the time-dependent changes of the axonal morphology.The changes beta-APP are quite regular and could be used for timing DAI injury.

The conformation of the brain plays an important role in the distribution of diffuse axonal injury in fatal road traffic accident

OBJETIVO: Foram estudadas as lesões encefálicas de 120 vítimas fatais de acidentes de trânsito, selecionadas aleatoriamente, com a finalidade de determinar a freqüência e distribuição topográfica da lesão axonal difusa (LAD) em relação com as estruturas encefálicas da linha média. MÉTODO: A identificação dos axônios foi efetuada com antisoro anti-proteínas do neurofilamento 70-, 160- e 210-kD obtido em camundongo. RESULTADOS: A LAD foi observada em 96 (80%) dos encéfalos examinados, tendo sido classificada em Grau 1 em 21,9%, Grau 2 em 51% e Grau 3 em 27,1% dos pacientes. A despeito da distribuição difusa que é característica da LAD, a lesão afetou preferencialmente as formações inter-hemisféricas (corpo caloso e fórnix) e a porção rostral do tronco encefálico, usualmente em um dos lados da linha média. CONCLUSAO: As formações inter-hemisféricas e a porção rostral do tronco encefálico funcionam, do ponto de vista mecânico, como estruturas de fixação dos hemisférios cerebrais durante a aceleração rotacional da cabeça. Sabe-se que a movimentação dos hemisférios cerebrais é retardada nas áreas de fixação, gerando aí maior estresse, particularmente no lado submetido ao maior deslocamento. O frequente envolvimento pela LAD das estruturas encefálicas centro-mediais profundas, usualmente em um dos lados da linha média, favorece o mecanismo acima proposto.

Resonancia magnética cerebral en daño axonal difuso / Cerebral magnetic resonance in diffuse axonal damage

El daño axonal difuso es causa importante de morbimortalidad y de secuela neuro-sicológica. En TC los hallazgos son pocos significativos o ausentes. La RM es el método diagnóstico más importante para la identificación del tipo de lesiones y ubicación de ellas. La secuencia de difusión es especialmente sensible para detectarlas, y la espectroscopía por RM puede dar información pronóstica.