Pulmonary microvascular dysfunction and pathological changes induced by blast injury in a rabbit model.

BACKGROUND: Vascular leakage has been proven to play a critical role in the incidence and development of explosive pulmonary barotrauma. Quantitatively investigated in the present study was the severity of vascular leakage in a gradient blast injury series, as well as ultrastructural evidence relating to pulmonary vascular leakage. METHODS: One hundred adult male New Zealand white rabbits were randomly divided into 5 groups according to distance from the detonator (10 cm, 15 cm, 20 cm, 30 cm, and sham control). Value of pulmonary vascular leakage was monitored by a radioactive 125I-albumin labeling method. Pathological changes caused by the blast wave were examined under light and electron microscopes. RESULTS: Transcapillary escape rate of 125I-albumin and residual radioactivity in both lungs increased significantly at the distances of 10 cm, 15 cm, and 20 cm, suggesting increased severity of vascular leakage in these groups. Ultrastructural observation showed swelling of pulmonary capillary endothelial cells and widened gap between endothelial cells in the 10-cm and 15-cm groups. CONCLUSION: Primary blast wave can result in pulmonary capillary blood leakage. Blast wave can cause swelling of pulmonary capillary endothelial cells and widened gap between endothelial cells, which may be responsible for pulmonary vascular leakage.

Local and distant trauma after hypervelocity ballistic impact to the pig hind limb.

The development of high-energy weapons could increase the velocity of projectiles to well over 1000 m/s. The nature of the injuries caused by the ballistic impact of projectiles at velocities much faster than 1000 m/s is unclear. This study characterizes the mechanical and biochemical alterations caused by high-speed ballistic impact generated by spherical steel ball to the hind limbs of the pig. That the local and distal injuries caused by hypervelocity ballistic impact to the living body are also identified. It is showed that the severity of the injury was positively correlated with the velocity of the projectile. And 4000 m/s seems to be the critical velocity for the 5.6 mm spherical steel ball, which would cause severe damage to either local or distal organs, as below that speed the projectile penetrated the body while above that speed it caused severe damage to the body. In addition, vaporization prevented the projectile from penetrating the body and the consequent pressure wave seems to be the causal factor for the distant damage.

Clinical relevance of tag single nucleotide polymorphisms within the CAT gene in patients with PTSD in the Chongqing Han population.

BACKGROUND: Free radical-induced oxidative damage of the brain has been implicated in a number of psychiatric disorders, including post-traumatic stress disorder (PTSD). Catalase (CAT) is a major antioxidant enzyme and a number of polymorphisms in CAT have been shown to be associated with several diseases, including hypertension, diabetes mellitus, Alzheimer's disease, and vitiligo. The aim of this study was to evaluate the association of CAT gene polymorphisms with PTSD in a case-control study. MATERIALS AND METHODS: A total of 460 unrelated adult Chinese Han adults, including 287 healthy volunteers and 173 patients with PTSD. Six tag single-nucleotide polymorphisms (tSNPs) were selected from the entire CAT gene through construction of haplotype bins, and they were genotyped using an improved multiplex ligation detection reaction (iMLDR) technique. Allelic frequencies and clinical characteristics were compared in two independent Chinese Han populations. RESULTS: Six tag SNPs were identified in the Chinese Han population and all were common SNPs. However, we could detect no evidence of genetic association between six tag SNPs in the CAT gene and PTSD in the Chinese Han population. CONCLUSIONS: This result suggests that six tag SNPs of the CAT gene may not be associated with PTSD, and that CAT gene might not influence the development of PTSD in patients following exposure to a traumatic event, also may be the sample sizes too small to allow a meaningful test.

Genetic distribution and association analysis of DRD2 gene polymorphisms with major depressive disorder in the Chinese Han population.

Dopamine D2 receptor is involved in reward-mediating mesocorticolimbic pathways. It plays an important role in major depressive disorder (MDD). Three gene polymorphisms Taq1A, C957T and -141C ins/del, were identified in the DRD2 gene among the Western population. These variants in the DRD2 gene might be associated with the susceptibility of MDD patients through affecting the bioeffects of endogenous dopamine neurotransmission. However, little is known about their occurrence in Chinese population and their association with the susceptibility of patients with major depressive disorder. In this study, a total of 338 unrelated adult Chinese Han population, including 224 healthy volunteers and 114 patients with major depressive disorder, were recruited. DRD2 polymorphisms (Taq1A and -141C ins/del) were detected using restriction fragment length polymorphism (RFLP) analysis and the C957T were detected by sequencing directly. As a result, three polymorphisms were identified in Chinese Han population and all were common SNP. However, we could detect no evidence of genetic association between 3 markers in DRD2 and major depressive disorder in the Chinese Han population. To conclude, this result suggests that Taq1A, C957T and -141C ins/del of DRD2 gene may not be associated with major depressive disorder, also may be the sample sizes too small to allow a meaningful test.

Treatment of rabbit femoral defect by firearm with BMP-4 gene combined with TGF-beta1.

BACKGROUND: Firearm bone fractures are difficult to treat compared with general ones as both soft tissue and bone are injured more extensively and severely with contamination in the wound track. The bone morphogenetic protein (BMP) and transforming growth factor (TGF)-beta play an important role in bone fracture healing. Therefore, BMP-4 combined with TGF-beta1 was used to improve and accelerate the repair of rabbit femoral defect resulting from firearm. METHODS: Femoral defect was made with 0.375 g steel ball fired at 350 m/s. At 6 hours after wounding, the debridement and irrigation were performed, followed by trimming the ends of defected bone at day 7. Plasmid-encoded BMP-4 gene identified in vitro and TGF-beta1 were injected into the tissue of upper and lower parts and the epicenter of the defected area at 2 weeks after wounding, again TGF-beta1 was given at 5 weeks. At 3, 7, 11, and 15 weeks after wounding, the expression of mRNA and protein of BMP-4 were detected by reverse transcription-polymerase chain reaction and Western blot. The activity of alkaline phosphatase and calcium content were measured for describing osteogenetic ability. The course and quality of osteogenesis were determined quantitatively by pathohistological and X-ray examinations. RESULTS: In vivo BMP-4 mRNA and protein could be continually expressed for 8 weeks. The determination of alkaline phosphatase activity and calcium content showed osteogenetic ability was significantly enhanced by BMP-4 gene combined with TGF-beta1. The pathohistological and X-ray examinations revealed that osteogenetic speed was prominently accelerated, and the quality was improved after the treatment. CONCLUSION: The repair of rabbit femoral defect resulting from firearm can be significantly improved and accelerated by BMP-4 gene combined with TGF-beta1.

[Effect of curcumin on growth and function of fibroblast in human hyperplastic scar].

OBJECTIVE: To seek an effective drug for treatment of human hyperplastic scar through studying the effects of curcumin on fibroblast growth and collagen synthesis. METHODS: Fibroblasts derived from scar tissue and from normal epidermal tissue were isolated and cultured separately with tissue-block method, their morphology were observed under invert phase contrast microscope, their growth curve was drawn respectively to determine the speed of growth. Then, fibroblasts from scar were stimulated with curcumin in different concentrations (0, 12.5, 25, 50 and 100 micromol/L) for detecting the inhibitory effect of curcumin on growth of fibroblasts using MTT methods and that on activity of procollagen alpha-1 gene transcription in fibroblast was detected by RT-PCR. RESULTS: The cell growth curve showed that double-multiplying time was 5 days in fibroblasts from scar and 4 days in those from normal dermis, showing significant difference between them (P < 0.05). MTT showed that curcumin in 12.5 micromol/L showed a cell proliferation enhancing trend, and its absorbance value was significantly higher than that in the normal group, but the effect turned to inhibition when concentration increased to over 25-100 micromol/L, and became significant inhibition at concentration of 50 and 100 micromol/L. Besides, curcumin also showed markedly inhibition on collagen type I synthesis in fibroblasts (P < 0.01). CONCLUSION: High concentration curcumin can inhibit effectively the fibroblast proliferation and collagen I synthesis in hyperplastic scar, therefore, may has therapeutic effect on the disease in human being.