The use of tourniquets in total knee arthroplasty (TKA) helps to obtain a blood-free operating space and clear anatomical landmarks, reduce the operation time and intraoperative bleeding and facilitate bone cement fixation. Arterial calcification is relatively common in the elderly people. There is still no consensus on whether it is safe to use tourniquets in patients with arterial calcification in total knee arthroplasty. Some studies showed that the use of tourniquets in patients with vascular calcification does not increase postoperative complications. Other studies showed that the use of tourniquets in patients with calcification will increase postoperative vascular complications. This article reviews the use of tourniquets in patients with vascular calcification. It is recommended that patients with vascular calcification should undergo detailed lower extremity vascular and cardiovascular assessments before surgery. The consult to a vascular surgeon is important. For patients with extensive vascular calcification, It's better to avoid the use of tourniquets during TKA to reduce possible complications.

Magnetic nano gene vector is one of the non-viral gene vectors, modified by functional group to bind cationic transfect reagents. Coupling magnetofection with the universal lipofection we developed a novel somatic cell transfection method as the so-called liposomal magnetofection (LMF). This approach is potential to provide somatic cell cloning with stable genetic cell lines to cultivate transgenic animals. In order to construct such liposomal magnetic gene vectors complexes system, we used nano magnetic gene vector to combine with liposomal cationic transfect reagents by molecular self-assembly. This vectors system successfully carried exogenous gene and then transfected animal somatic cells. Here, we conducted atomic force microscopy (AFM), zeta potential-diameter analysis and other characterization experiments to investegate the size distribution and morphology of magnetic nanoparticles, the way of the vectors to load and concentrate DNA molecules. Our data reveal that, the LMF of Pig Kidney cells exhibited higher transfection efficiency comparing with the transfection mediated by the commercial lipofectamine2000. Moreover, LMF method overcomes the constraint of transient expression mediated by lipofection. Meanwhile, MTT assay showed low cytotoxicity of LMF. Hence, LMF is a feasible, low cytotoxic and effective method of cell transfection.
Animals ; Cations ; Cell Line ; DNA ; Genetic Vectors ; Kidney ; cytology ; Liposomes ; Magnetics ; Nanoparticles ; Swine ; Transfection

A case report of periprosthetic hip clostridium perfringens infection 13 years after total hip arthroplasty, the patient had hip pain with fever for one week. Physical examination and imaging examination confirmed the periprosthetic joint infection. The pathogenic bacterium was clostridium perfringens according to bacterial culture, and the pathogenic bacterium of clostridium perfringens was suspected relating to the gallbladder disease in this patient. Considering such periprosthetic joint infection was early stage hematogenous periprosthetic joint infection, treatment of debridement, retention of the prosthesis, irrigating, and indwelling drainage tube were conducted. By reviewing literature about periprosthetic clostridium perfringens infection, only seven reports of periprosthetic joint infection were caused by clostridium perfringens, which were all case reports. From the previous case reports and our case, we found that the infection around the prosthesis caused by clostridium perfringens was limited to the area around the joint, and prognosis of such cases may not be as severe as the natural gas gangrene which developed very rapidly, but great attention should be paid to. The hematogenous periprosthetic joint infection caused by clostridium perfringens who had gastrointestinal symptoms in the early stage should be highly suspicious of gallbladder lesions and thorough debridement, retention of the prosthesis, irrigating and indwelling drainage tube maybe a treatment method.