Expressions of TGF-β1 and EⅢA-FN after Rat Skeletal Muscle Contusion and Wound Age Estimation

Abstract

Objective To study the expressions of transforming growth factor-β1 （TGF-β1） and EⅢA-fibronectin （EⅢA-FN） at different time points of antemortem injury, antemortem injury postmortem expression and postmortem injury and to explore their application value in wound age estimation. Methods A model of rat skeletal muscle contusion was established. The rats were randomly divided into normal control group （n=5）, antemortem contusion group （n=40）, antemortem contusion postmortem expression group （n=110） and postmortem injury group （n=25）. The expressions of TGF-β1 and EⅢA-FN after rat skeletal muscles antemortem contusion were detected with immunohistochemical staining. Expression changes of TGF-β1 and EⅢA-FN mRNA in each group were analyzed with real-time fluorescence quantitative PCR. Results Immunohistochemical staining results showed that a large number of polymorphonuclear leukocyte, mononuclear cells and fibroblastic cells showed a strong expression of TGF-β1 in wounded zones 12 h-14 d after antemortem contusion. EⅢA-FN was mainly distributed in the extracellular matrix, 3 to 7 d post-traumatic. Real-time fluorescence quantitative PCR results showed that TGF-β1 and EⅢA-FN mRNA in antemortem injury group reached the peak at 3 and 5 d post-traumatic respectively. The expressions of TGF-β1 and EⅢA-FN mRNA in antemortem contusion postmortem expression group peaked at 6 h and 12 h postmortem. The expression of TGF-β1 and EⅢA-FN mRNA in postmortem injury group 0.5-12 h postmortem was significantly lower than those of the normal control group and the antemortem contusion group. Conclusion TGF-β1 and EⅢA-FN might become a reference index for skeletal muscle wound age estimation.

The distribution of the growth factors FGF-2 and VEGF, and their receptors, in growing red deer antler

The cellular distributions of the growth factors FGF-2 and VEGF, and their receptors FGFR1, FGFR2 and FGFR3, and VEGFR-2 respectively, were visualized by immunohistochemistry and light microscopy in sections of growing red deer antler. Both of these signalling systems were widely expressed in the integument and osteocartilaginous compartments. FGF-2 was found in the same cells as all three FGFRs, indicating that FGF signalling may be principally autocrine. The patterns of labelling for VEGF and its receptor were similar to those seen for FGF-2 and FGFR-3, in both compartments. Our data are consistent with the findings of others in suggesting that FGF-2 induces expression of VEGF, to stimulate and maintain high rates of neovascularisation and angiogenesis, thereby providing nutrients to both velvet and bone as they rapidly grow and develop. The presence of FGF and VEGF and their receptors in epithelial cells suggests that these signalling systems play a role in skin development, raising the possibility that one or both may be involved in the close coupling of the coordinated growth of the integument and osteocartilage of antler, a process which is poorly understood at present.

Ornithine transcarbamylase deficiency

Two infants, one male and one female, with elevated serum ammonia levels, were shown, based on urine organic acid analysis and DNA studies, to have ornithine transcarbamylase (OTC) deficiency. OTC deficiency is one of the most common urea cycle disorders. Hyperammonemia occurred at 3 days of age in the male infant, and at approximately 7 days of age in the female infant. Administration of sodium benzoate and sodium phenylacetate lowered the serum ammonia level effectively in both cases. Other modalities, including peritoneal dialysis and protein restriction, were also important in the control of the serum ammonia level. The mother of the male infant was shown to be a carrier of the OTC gene mutation by allopurinol loading test. The mutation site of the OTC gene for the female infant was identified, but her mother did not have the mutation. OTC deficiency, an incompletely dominant X-linked disorder, is a severe disease even for females and prompt treatment and precise genetic counseling are mandatory.