ABSTRACT
OBJECTIVES: To investigate effects of platelet-rich plasma on tendon cell proliferation and the underlying molecular mechanisms. MATERIALS AND METHODS: Platelet-rich plasma was prepared manually by two-step centrifugation. Proliferation was evaluated in cultured rat tendon cells by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay. Cell cycle progression was assessed by flow cytometry. Messenger RNA expression of proliferating cell nuclear antigen (PCNA), cyclin E1, A2 and B1, and cyclin-dependent kinases (Cdks) 1 and 2 was assessed by real-time polymerase chain reaction. Protein expression of the above cyclins and Cdks and of signal transducer and activator of transcription (Stat) 3 and p27 was evaluated by western blotting. RESULTS: Platelet-rich plasma used in the present study had concentrations of platelets, TGF-ß1 and PDGF over 3-fold higher than normal whole blood. Platelet-rich plasma enhanced tendon cell proliferation (P = 0.008) by promoting G1 /S phase transition in the cell cycle, and increased expression of PCNA, cyclin E1, A2 and B1, Cdks1 and 2, and phosphorylated Stat3, while inhibiting p27 expression. CONCLUSIONS: Platelet-rich plasma contains high concentrations of TGF-ß1 and PDGF that increase tendon cell proliferation by modulating Stat3/p27(Kip1), which enhances expression of cyclin-Cdk complexes that promote cell cycle progression. These results provide molecular evidence for positive effects of platelet-rich plasma on tendon cell proliferation, which can be useful in clinical applications of tendon injury.
Subject(s)
Cell Proliferation , Cyclin-Dependent Kinase Inhibitor p27/metabolism , Cyclin-Dependent Kinases/genetics , Cyclins/genetics , Platelet-Rich Plasma/metabolism , STAT3 Transcription Factor/metabolism , Tendons/cytology , Animals , CDC2 Protein Kinase , Cyclin-Dependent Kinase 2/genetics , Platelet-Derived Growth Factor/metabolism , RNA, Messenger/genetics , Rats , Transforming Growth Factor beta/metabolism , Up-RegulationSubject(s)
AIDS-Related Opportunistic Infections/complications , Duodenal Diseases/etiology , Gastrointestinal Hemorrhage/etiology , Pancreatic Diseases/complications , Tuberculosis/complications , Adult , Duodenal Diseases/therapy , Duodenoscopy , Embolization, Therapeutic , Gastrointestinal Hemorrhage/therapy , Humans , Male , Mycobacterium tuberculosis , Pancreatic Diseases/microbiology , Young AdultABSTRACT
STUDY DESIGN: A case report of spinal arteriovenous malformation presented as chest pain in a child. OBJECTIVES: To illustrate the atypical clinical presentation as right chest pain in a child with spinal cord arteriovenous malformation. SETTING: Chang Gung Memorial Hospital and Chang Gung University, Taiwan. CASE REPORT: An 8-year-old boy was diagnosed with spinal cord arteriovenous malformation after paraplegia. However, early diagnosis was delayed for the atypical initial clinical presentation as chest pain. After surgery and rehabilitation for 6 months, the patient could walk without assistance. CONCLUSIONS: Correct diagnosis of spinal cord arteriovenous malformations is sometimes difficult in children with atypical presentations. Early diagnosis relies on detailed examination and high index of suspicion.
