Osteosarcoma is the most common primary bone malignancy among children and adolescents. We investigated whether benzamil, an amiloride analogue and sodium-calcium exchange blocker, may exhibit therapeutic potential for osteosarcoma in vitro. MG63 and U2OS cells were treated with benzamil for 24 hours. Cell viability was evaluated with the MTS/PMS assay, colony formation assay, and flow cytometry (forward/side scatter). Chromosome condensation, the terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay, cleavage of poly-ADP ribose polymerase (PARP) and caspase-7, and FITC annexin V/PI double staining were monitored as indicators of apoptosis. Intracellular calcium was detected by flow cytometry with Fluo-4 AM. The phosphorylation and activation of focal adhesion kinase (FAK) and signal transducer and activator of transcription 3 (STAT3) were measured by western blot. The expression levels of X-linked inhibitor of apoptosis protein (XIAP), B-cell lymphoma 2 (Bcl-2), B-cell lymphoma-extra large (Bcl-xL), SOD1, and SOD2 were also assessed by western blot. Mitochondrial status was assessed with tetramethylrhodamine, ethyl ester (TMRE), and intracellular adenosine triphosphate (ATP) was measured with BioTracker ATP-Red Live Cell Dye. Total cellular integrin levels were evaluated by western blot, and the expression of cell surface integrins was assessed using fluorescent-labelled antibodies and flow cytometry.Aims
Methods
Nerve damage is a complication of THA and TKA procedures. The incidence of subclinical nerve injury following arthroplasty is unknown. The aim was to determine the prevalence of asymptomatic nerve deficits in an arthroplasty population group, and the incidence of post-operative changes in nerve function. A Secondary aim was to identify the nature of any deficits. And the association between nerve deficits and history of backache. A non-randomised prospective series of patients undergoing lower limb arthroplasty for osteoarthritis were studied at a single hospital. The peroneal nerve was investigated using nerve conduction in forty patients. Twenty patients had upper limb testing to differentiate between a polyneuropathy or isolated lower limb neuropathy. Nerve function deficits were detected in the peroneal nerve in fifteen patients pre-operatively and fifteen post-operatively, of those twelve had A waves detected suggestive of a generalised neuropathy. Ten patients who had upper limb testing had a conduction defect (five had asymptomatic Carpal tunnel). There was a positive correlation between presence of post-operative deficit and age(r=0.389, p=0.013). A negative correlation was found for presence of post-operative A waves and BMI(r=−0.370, p=0.019). The prevalence of pre-operative subclinical peroneal neuropathy is much higher than expected in this group (37.5%) of arthroplasty patients. There is a strong correlation between presence of post-operative conduction abnormalities and age. There is no relationship between peripheral neuropathy and history of backache or residual post-operative deficit.
The size selection of the outer metal shell to fit the acetabulum is a dilemma to the surgeons for the bipolar hemiarthroplasty. However, no body ever mentioned the final results of motion behaviour of bipolar hip endoprostheses by different size selections of outer metal shell. The purpose of this study was to evaluate the motion behaviour of bipolar hip endoprostheses under different sizes of outer metal shell. A fresh cadaver of size of 50 mm and three different sizes of bipolar hip endoprostheses were used to evaluate the motion behaviour of bipolar hip endoprostheses under the MTS machine. Each size had six sets of bipolar hip endoprostheses to get statistical data. The single axial load scaled from 300 N to 3000 N with increment of 300 N was applied on both the inner bearing and outer bearing to obtain the frictional torque of two bearings randomly. The axis was rotated from 0° to 90° under the speed of 1 deg/sec. The motion behaviour of bipolar hip endoprostheses was predicted and verified by the comparison of the frictional torque of both bearings and repeat the experiments again. The dynamic frictional torque of 48mm was larger than the dynamic frictional torque of the 50mm at the inner bearing. The size of 52mm had the largest value of dynamic frictional torque for the outer bearing under any load condition. The prosthesis that had larger outer metal shell than the acetabulum had the same relative motion behaviour as the design hypotheses, because the difference of frictional torque was much higher. In conclusion, the motion of the bipolar hip endoprostheses is influenced by the frictional behaviour of the both bearings. The relative motion of bipolar hip endoprostheses with a larger outer shell size will have an idea relative motion behaviour, because the larger difference of frictional torque. The thickness of the UHMWPE has a positive effect to reduce the friction between the UHMWPE liner and metal head.
