DNA topoisomerase I and II expression in drug resistantgerm cell tumours

A small number of testicular germ cell tumours are refractory to current chemotherapy regimens. DNA topoisomerase I is the target for several new drugs and a potential candidate treatment for chemorefractory germ cell tumours. DNA topoisomerase IIα is the target for etoposide, which is currently used regularly in germ cell tumour treatment. The expression of DNA topoisomerase I and IIα were therefore assessed immunohistochemically in a range of testicular tumours, especially those with persistent malignant elements on retroperitoneal lymph node dissection. Pre-chemotherapy orchidectomy specimens were matched with post-chemotherapy retroperitoneal lymph node dissections to examine changes in expression. There was considerable variation in the expression of topoisomerase I in different tumour types. Both yolk sac tumours and teratoma, mature showed universal expression of topoisomerase I, while 38% of seminomas and 30% of embryonal carcinomas were positive. Strong topoisomerase IIα expression was found in embryonal carcinoma. There was a negative correlation between topoisomerase I and IIα expression (P=0.004) and downregulation of topoisomerase IIα after chemotherapy (P=0.02). Topoisomerase I expression appears to increase in those cases with residual teratoma, mature, but is largely unchanged in those cases remaining as embryonal carcinoma. These results suggest that topoisomerase I inhibitors may be useful in chemorefractory germ cell tumours, especially yolk sac tumours and where there are unresectable residual teratoma, mature deposits

The role of extracellular vesicles in malaria biology and pathogenesis

In the past decade, research on the functions of extracellular vesicles in malaria has expanded dramatically. Investigations into the various vesicle types, from both host and parasite origin, has revealed important roles for extracellular vesicles in disease pathogenesis and susceptibility, as well as cell-cell communication and immune responses. Here, work relating to extracellular vesicles in malaria is reviewed, and the areas that remain unknown and require further investigations are highlighted

Case Reports: Tantalum Debris Dispersion During Revision of a Tibial Component for TKA

Porous tantalum nonmodular tibial components for TKA were introduced in 1999. We revised three well-fixed tantalum tibial trays. For removal, we used osteotomes and revision oscillating saw blades. Removal of the components was laborious and resulted in generation of abundant tantalum debris that seeded the periarticular soft tissues despite meticulous protection with gauze. The retained metallic debris that is visible on postoperative radiographs has the potential for generation of third-body wear. We alert the orthopaedic community about this phenomenon and recommend minimizing the use of motorized revision instruments for removal of trabecular metal implants