title: Enhancement of Apoptosis by Titanium Alloy Internal Fixations during Microwave Treatments for Fractures: An Animal Study.
abstract: OBJECTIVE
  Microwaves are used in one method of physical therapy and can increase muscle tissue temperature which is useful for improving muscle, tendon and bone injuries. In the study, we sought to determine whether titanium alloy internal fixations influence apoptosis in tissues subjected to microwave treatments at 2,450 MHz and 40 W during the healing of fractures because this issue is not yet fully understood.
  
  
  METHODS
  In this study, titanium alloy internal fixations were used to treat 3.0-mm transverse osteotomies in the middle of New Zealand rabbits' femurs. After the operation, 30-day microwave treatments were applied to the 3.0 mm transverse osteotomies 3 days after the operation. The changes in the temperatures of the muscle tissues in front of the implants or the 3.0 mm transverse osteotomies were measured during the microwave treatments. To characterize the effects of titanium alloy internal fixations on apoptosis in the muscles after microwave treatment, we performed TUNEL assays, fluorescent real-time (quantitative) PCR, western blotting analyses, reactive oxygen species (ROS) detection and transmission electron microscopy examinations.
  
  
  RESULTS
  The temperatures were markedly increased in the animals with the titanium alloy implants. Apoptosis in the muscle cells of the implanted group was significantly more extensive than that in the non-implanted control group at different time points. Transmission electron microscopy examinations of the skeletal muscles of the implanted groups revealed muscular mitochondrial swelling, vacuolization. ROS, Bax and Hsp70 were up-regulated, and Bcl-2 was down-regulated in the implanted group.
  
  
  CONCLUSIONS
  Our results suggest that titanium alloy internal fixations caused greater muscular tissue cell apoptosis following 2,450 MHz, 40 W microwave treatments in this rabbit femur fracture models.
authors.affiliation: Department of Rehabilitation Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Wang
authors.affiliation: Department of Rehabilitation Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
authors.forename: Yiming
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Department of Biostatistics, Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Lina
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Rehabilitation Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
authors.forename: Dongmei
authors.initials: D
authors.lastname: Ye
authors.affiliation: Department of Rehabilitation Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
authors.forename: Xianxuan
authors.initials: X
authors.lastname: Feng
authors.affiliation: Department of Rehabilitation Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
authors.forename: Tengfei
authors.initials: T
authors.lastname: Fu
authors.affiliation: Department of Rehabilitation Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
authors.forename: Yuehong
authors.initials: Y
authors.lastname: Bai
mesh_terms: D000497:Alloys / Q000528:radiation effects*; D000818:Animals; D001831:Body Temperature; D003972:Diathermy / Q000009:adverse effects* / Q000379:methods; D005269:Femur / Q000293:injuries* / Q000473:pathology; D005593:Fracture Fixation, Internal / Q000295:instrumentation*; D017102:Fracture Healing / Q000528:radiation effects*; D020869:Gene Expression Profiling; D018840:HSP70 Heat-Shock Proteins / Q000096:biosynthesis / Q000235:genetics; D006358:Hot Temperature / Q000009:adverse effects; D020287:In Situ Nick-End Labeling; D016268:Internal Fixators / Q000009:adverse effects; D008297:Male; D008872:Microwaves / Q000009:adverse effects* / Q000627:therapeutic use; D008931:Mitochondria, Muscle / Q000473:pathology*; D009124:Muscle Proteins / Q000096:biosynthesis / Q000235:genetics; D018482:Muscle, Skeletal / Q000473:pathology; D010027:Osteotomy; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis / Q000235:genetics; D011817:Rabbits; D017382:Reactive Oxygen Species / Q000032:analysis; D014025:Titanium / Q000528:radiation effects*; D051028:bcl-2-Associated X Protein / Q000096:biosynthesis / Q000235:genetics
chemical_list: D000497:Alloys; D018840:HSP70 Heat-Shock Proteins; D009124:Muscle Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D017382:Reactive Oxygen Species; D051028:bcl-2-Associated X Protein; D014025:Titanium