[The Effects of PKCι on Anti-tumor Activity of Cytokine-induced Killer Cells Against Pancreatic Cancer Cells and the Possible Underlying Mechanisms].

OBJECTIVE: To study the impact of atypical protein kinase Cι (PKCι) isoform PKC on the pancreatic cancer cells towards the tumoricidal effect of cytokine-induced killer (CIK) cells and explore its mechanisms. METHODS: CIK cells were prepared by inducing mononuclear cells isolated from the peripheral blood of healthy people with interleukin-2 (IL-2), interferon (IFN) and CD3 mAb and subsequently co-cultured with pancreatic epithelial cell HPDE6-C7, pancreatic cancer cells MiaPaCa and PANC-1 with or without PKC inhibitor named sodium thiomalate (ATM). All cells were divided into control group, ATM group, co-culture group with CIK and co-culture group with CIK+ATM. Cell count was used to detect the growth of each group from 1 to 8 d. Flow cytometry was used to detect the death rate of the cell lines after 48 h cell culture in each group. The small hairpin RNA (shRNA) was used for PKCι knockdown and the recombinant plasmid transfection was for PKCι overexpression in pancreatic cancer cells. Western blot and real-time fluorescent quantitative PCR (qRT-PCR) were utilized to determine the expression of PKCι protein and the impact on gene expression of transforming growth factor-ß (TGF-ß), a downstream effector modulated by PKC. Different mass concentrations of TGF-ß (1, 10, 20 ng/mL) were added into the co-culture of MiaPaCa and PANC-1 with CIK. The cell death rate was detected by flow cytometry 48 h later, so as to explore the possible mechanisms of the impact of PKCι on the tumoricidal effects of CIK cells. RESULTS: ATM and CIK were shown to suppress the growth and induce apoptosis or death of pancreatic cancer cells, meanwhile, ATM can enhance the tumoricidal effect of CIK on pancreatic cancer cells. Moreover, we found that PKCι knockdown in pancreatic cancer cells can down-regulate the gene expression of TGF-ß. In return, PKCι overexpression in pancreatic cancer cells can increase the gene expression of TGF-ß. The death rate of cancer cells with 10, 20 ng/mL TGF-ß was lower compared with the control group (P < 0.05). CONCLUSIONS: PKCι knockdown in pancreatic cancer cells can not only inhibit the growth of pancreatic cancer cells, but also enhance the tumoricidal effects of CIK on cancer cells. The possible mechanism of PKCι is to affect the immune escape of tumor cells by regulating the expression of TGF-ß.

An Early Periprosthetic Fracture of a Cementless Oxford Unicompartmental Knee Arthroplasty: Risk Factors and Mitigation Strategies.

INTRODUCTION: The cementless Oxford partial knee arthroplasty is associated with low perioperative complications and good long-term survival rates. However, perioperative fractures remain a serious morbidity for patients. CASE REPORT: This case report describes an early post-operative tibial periprosthetic fracture through the keel slot, which we believe may be contributed by the deep implant keel design and the presence of a narrow metaphysis in the Asian knee. The patient subsequently underwent a revision total knee replacement and fixation of the periprosthetic fracture. CONCLUSION: This paper discusses the ways to identify patients at high risk of developing periprosthetic fractures and to minimize such occurrences, including adopting a modified tibial preparation, doing precise saw cuts, and considering a cemented tibial implant.

The utility of mini C-arm in the fixation of unstable paediatric supracondylar humeral fractures.

BACKGROUND: Pediatric supracondylar humerus fractures have traditionally been reduced and fixed with conventional C-arm (CCA) fluoroscopy guidance. With the increase in popularity of the newer mini C-arm (MCA) system within other fields of surgery due to its ease of use and lower radiation emission, the same adoption should be explored in pediatric orthopedic surgeries. The purpose of this study is to compare the MCA and CCA primarily in reduction and fixation outcomes and secondarily in other perioperative parameters. METHODS: Retrospective analysis of 193 patients who underwent surgical fixation for displaced supracondylar humerus fractures. 44 and 149 cases were performed with the MCA and CCA respectively. Baumann's angle and the intersection of anterior humeral line (AHL) were assessed on postoperative anterior posterior and lateral radiographs and adequate reduction was defined by an angle between 64 and 81˚, and AHL intersecting middle third of the capitellum. Surgical time, fluoroscopy duration, number of images and radiation exposure were obtained from the surgical notes. RESULTS: Amongst the CCA cases, there were greater satisfactory coronal plane reduction (p < 0.05), while no difference in sagittal plane accuracy (p > 0.05) was seen. In MCA group, longer surgical (p < 0.05) and fluoroscopy times (p < 0.05), and greater number of shots (p < 0.05) was noted. However overall radiation exposure in the MCA group was still lower (p < 0.05). CONCLUSION: The MCA system is potentially less accurate in coronal plane reduction and more challenging to use. However, pitfalls can easily be avoided. Usage should be advocated as overall radiation exposure can be reduced. LEVEL OF EVIDENCE: Level III retrospective comparative study.