Effects of low intensity pulsed ultrasound on healing of denervated Tibial fracture in the rabbit

Low intensity pulsed ultrasound [LIPUS] has been shown in healing of fractures. This study investigates the effect of LIPUS as a fracture-healing adjunct on the denervated tibial fractures in rabbit model. Twenty four male Dutch rabbits were randomly divided into four groups including two control and two ultrasound-treated [US-treated] groups. A standardized mid-tibial osteotomy was performed in the right tibia. Ipsilateral sciatic nerve was cut two centimeter above the right knee. After three days, the rabbits of US-treated groups received the therapeutic dose [100 mW/cm[]] of ultrasound for 15 minutes per day until the 6th and 8th week and the control groups did not receive any treatment. The rabbits were sacrificed at weeks 6th and 8th post surgery and the external fixator and tibia were carefully removed. Radiographs were taken by lateral and anteroposterior views. Mechanical testing of rabbit's tibiae was used. The specimens were taken from callus of fracture for histomorphometric study of trabecula in the fractured area. Immunohistochemical staining for ki67 was used to evaluate cellular proliferation. Radiographs showed the callus was visible indicating the ossification of the callus tissue without any significant difference between US- treated and control groups. Biomechanical, histomorphic and immunohistochemical evaluations had no significant difference between control and US-treated groups after 6 and 8 weeks postoperation. These finding suggest that ultrasound therapy with features which applied in this study had no significant effect on denervated tibial fracture repair in rabbits

[Study of the effects of hexamethylentetramine on decrease of defects of the lung tissue in the rat exposed to sulfur mustard]

The aim of this study was to evaluate the effects of HMT on protection of lung tissue exposed to HD in the rat. In this study twenty Albino Wistar adult male rats weighting 200 +/- 20 gram were used. Rats divided randomly into 4 groups [each group has 5 rats] as below: Normal saline group [NS], HMT group, HD group [0.25% HD] and HD+HMT group. Normal saline and HD solution were injected by intra tracheal catather. Animals in HMT and HD+HMT groups received HMT by intra peritoneal injection for 14 days daily. All rats were killed after 14 days, a part of lung tissue were removed, fixed and processed for histological evaluation by H and E staining and apoptotic cell death study by TUNEL kit. In addition, biochemical study [catalase enzyme] was measured in all groups. Histological examination and cell counting data revealed that there were no significant differences between Saline and HMT groups. Alveolar hemorrhage and inflammation, as well as, the number of apoptotic cells in the HD group was significantly increased when compared to HD+HMT group. HMT have prophylactic and therapeutics effects in the lung tissue against HD

[Study of the effects of intermittent low-intensity pulsed ultrasound on callus formation of tibia in rabbit [a radiological and biomechanical evaluation]]

Application of low intensity ultrasound has been used for treatment of many diseases in medicine and has suggested for accelerating wound healing process, modifying scar tissue and relief of pain. The aim of this study was radiological and biomechanical evaluation of low-intensity pulsed ultrasound on callus formation of tibia in rabbit. In this experimental study 20 male white Dutch rabbits [weighting 2.5-3kg] aged about 6 months were used. Under general anesthesia and sterile condition a standardized mild-tibial osteotomy was performed in the right tibia and bilateral external fixator was applied to the lateral aspect. The rabbits were randomly divided into control and ultrasound groups. After three days of surgery the rabbits of ultrasound group received ultrasound with 1MHz and pulsed 1:1 and 50 and 100 mw/cm[2] for 15 min/day and the control groups did not received any treatment. The rabbits were killed at week 7 post surgery by inhalation of chloroform. Radiographs were taken following killing the animals immediately. Biomechanical test of rabbits tibiae were used and the samples were taken from the callus of fracture. Radiological scoring of tibia according to density of mineralized callus in the control group was 3.5 +/- 0.35 and in the ultrasound group [50mw/cm[2]] was 2.55 +/- 0.25 and in the ultrasound group [100mw/cm[2]] was 3.25 +/- 0.38. Thus there was it has no differences between ultrasound and control group in radiographs. Force maximum in the biomechanical test of the tibia in the control group was 65.75 +/- 6.16 and in the ultrasound group [50mw/cm[2]] was 49.42 +/- 5.27 and in the ultrasound group [100mw/cm[2]] was 79.12 +/- 9.63, the differences were not significant. These finding suggest that programmed ultrasound therapy has no effect on facture repair and callus formation of rabbits tibiae