Zheng-guo Wang

Plasma cytokines and endotoxin levels in patients with severe injury and their relationship with organ damage

In 17 patients plasma TNF-alpha and IL-8 were assayed with enzyme-linked immunosorbent assay. IL-6 activity in plasma was determined by bioassay with IL-6-dependent cell line 7TD1. The limulus amoebocyte lysate chromogenic test was used for plasma endotoxin assay. Plasma cytokine levels in injured patients were significantly increased. Plasma TNF-alpha was shown to be increased earlier, while an increase in plasma IL-6 and IL-8 levels occurred late, all of which were shown to be significantly positively correlated with ISS, cardiac and hepatic enzyme activities, and index of renal function. In addition, obvious endotoxaemia occurred at an early stage of injuries, which was respectively significantly correlated with ISS and plasma TNF-alpha, IL-6 and IL-8 levels. Severe injuries could induce increased successive release of TNF-alpha, IL-6 and IL-8, and obvious endotoxaemia. The post injury release of cytokines might be related to endotoxaemia, and may play an important role in the development of organ damage after injury.

Motorcycle accidents in China

OBJECTIVEnTo analyze the characteristics and causes of motorcycle accidents in China from 2000 to 2005.nnnMETHODSnWe collected data on possession of motorcycles and automobiles, number of traffic crashes, casualty and economic loss from 2000-2005 Statistic Annual Report of Traffic Management Bureau, Ministry of Public Security of China. The data was processed statistically by SPSS 11.0 software package.nnnRESULTSnDuring 6 years, the number of motorcycle accidents were up to 122,300 in 2003, which was the highest, and then gradually decreased. However, the casualty had the tendency of consistent increase, for example, the motorcycle accidents resulted in 26,200 deaths and 157,500 injuries in 2005. The mortality per 10, 000 motorcycles and the ratio of deaths to injuries were lower than those of automobiles, but the mortality per 100 motorcycle accidents was significantly higher than that of automobiles (P less than 0.01).nnnCONCLUSIONSnChina has attached great importance to the management of traffic safety, which is beneficial to control and reduce traffic accidents in recent years. However, the casualty keeps increasing annually. Therefore, it is urgent to strengthen the management of motorcycles, promote the education of motorcyclists, take effective traffic measures and improve the first-aid system of traffic injuries.

Intrapulmonary Expression of Scavenger Receptor and CD14 and Their Relation to Local Inflammatory Responses to Endotoxemia in Mice

This study was first designed to investigate systematically the kinetics of surface expression of scavenger receptors (SRs) and CD14 on alveolar macrophages in vivo and in vitro and their relation with local pro- and antiinflammatory responses in endotoxemia. The expression of SR and CD14 in lungs was down- and up-regulated, respectively, in the presence of endotoxemia, which might be due to decreased expression of SR and increased expression of CD14 on the surface of the resident macrophages. Down-regulation of SRs on alveolar macrophages not only induces decreased defensive function of the macrophages, it also enhances lipopolysaccharide (LPS)-induced activation of alveolar macrophages possibly through increasing LPS binding to CD14. Although CD14 is a key receptor responsible for LPS to activate macrophages, both phospholipase C and anti-CD14 antibody can completely inhibit activation of alveolar macrophages initiated by only LPS 1 ng/ml, as determined by tumor necrosis factor-{alpha} (TNF{alpha}) production, but it does not significantly change TNF{alpha} release upon cell stimulation by LPS 10 {mu}g/ml. There was an intrinsic relation of enhanced intrapulmonary pro- and antiinflammatory responses with changes in SR and CD14 expression, which suggests that the down-regulation of SR and up-regulation of CD14 might be an important mechanism for the lung to change from a defense organ to an effector organ during sepsis.n

Sustained Vascular Endothelial Growth Factor Blockade by Antivascular Endothelial Growth Factor Antibodies Results in Nonunion in the Process of Fracture Healing in Rabbits

OBJECTIVEnTo study the role of vascular endothelial growth factor (VEGF) in the process of fracture healing and the effect of VEGF and anti-VEGF polyclonal antibody on fracture healing.nnnMETHODSnOne hundred and five New Zealand white rabbits were subjected to fracture of the middle part of the left radius, and were randomly divided into control, VEGF, and VEGF polyclonal antibody groups. The blood flow at the fracture site was measured by single photoemission computerized tomography after 8 hours, 24 hours, and 72 hours, and 1 weeks, 3 weeks, 5 weeks, and 8 weeks. X-ray films were taken after 1 weeks, 3 weeks, 5 weeks, and 8 weeks to observe the results of fracture healing.nnnRESULTSnThe blood flow at the fracture site in the VEGF group significantly increased compared with the control group during 8 hours to 1 week, but no obvious difference was seen on the X-ray films between the two groups. In the VEGF polyclonal antibody group, the blood flow at the fracture sites decreased significantly at all time points compared with the control group. The fracture healing process was disturbed, and nonunion signs were seen at the fracture site.nnnCONCLUSIONSnThe lack of VEGF may impede the fracture healing process, and results in nonunion at the fracture site.

Vascular endothelial growth factor and its receptor expression during the process of fracture healing.

OBJECTIVEnTo study the expression regularity of vascular endothelial growth factor (VEGF) during the process of fracture healing, and the type of VEGF receptor expressed in the vascular endothelial cells of the fracture site.nnnMETHODSnThe fracture model was made in the middle part of left radius in 35 rabbits. The specimens from the fracture site were harvested at 8, 24, 72 hours and 1, 3, 5, 8 weeks, and then fixed, decalcified, and sectioned frozenly to detect the expression of VEGF and its receptor at the fracture site by in situ hybridization and immunochemical assays.nnnRESULTSnVEGF mRNA and VEGF expression was detected in many kinds of cells at the fracture site during 8 hours to 8 weeks after fracture. Flt1 receptor of VEGF was found in the vascular endothelial cells at the fracture site during 8 hours to 8 weeks after fracture, and strong expression of flk1 receptor was detected from 3 days to 3 weeks after fracture.nnnCONCLUSIONSnThe expression of VEGF and flt1 receptor appears during the whole course of fracture healing, especially from 1 to 3 weeks. Flk1 receptor is highly expressed in a definite period after fracture. VEGF is proved to be involved in the vascular reconstruction and fracture healing.