No abstract

Understanding the molecular mechanisms underlying the biosynthetic interactions between particular nanomaterials with specific cells or proteins opens new alternatives in nanomedicine and nanotoxicology. Multiwalled carbon nanotubes (MWCNTs) have long been explored as drug delivery systems and nanomedicines against cancer. There are high expectations for their use in therapy and diagnosis. These filaments can translocate inside cultured cells and intermingle with the protein nanofilaments of the cytoskeleton, interfering with the biomechanics of cell division mimicking the effect of traditional microtubule-binding anti-cancer drugs such as paclitaxel. Here, it is shown how MWCNTs can trigger significant anti-tumoral effects in vivo, in solid malignant melanomas produced by allograft transplantation. Interestingly, the MWCNT anti-tumoral effects are maintained even in solid melanomas generated from paclitaxel-resistant cells. These findings provide great expectation in the development of groundbreaking adjuvant synthetic microtubule-stabilizing chemotherapies to overcome drug resistance in cancer.

Scedosporium prolificans is an emerging opportunistic fungal agent encountered in severely neutropenic patients. The purpose of this paper is to describe the main cranial CT findings from a retrospective review of six patients (four men and two women, 18-66 years old) afflicted with disseminated infection by S. prolificans with neurological symptoms. They were severely neutropenic and presented with severe respiratory failure and conscience deterioration, with a subsequent 100% mortality. The final diagnosis was established by autopsy (performed in five patients) and blood culture findings. Cranial CT showed multiple low-density lesions in four patients without contrast enhancement located in the basal ganglia and corticomedullary junction. Autopsy findings of these lesions demonstrated necrosis and hyphae proliferation inside brain infarcts. Also, two of the patients had a subarachnoid hemorrhage, but angiography could not be performed. CT and autopsy findings were fairly similar to those encountered in cerebral aspergillosis; however, possibly because of its rapid and fatal evolution, no edema or ring enhancing lesions were encountered. Thus, Scedosporium can be included as a rare but possible cause of invasive fungal disseminated central nervous system infections in severely neutropenic patients.

Perianal basal cell carcinoma is a very rare tumor accounting for only 0.2% of the anorectal tumors. It must be distinguished from basaloid carcinoma of the anus, which resembles it histologically but shows a much more aggressive behavior, metastasizes early, and often proves fatal, thus requiring different therapy. Differential diagnosis of both entities by light microscopy may be difficult. Five cases of perianal basal cell carcinoma and five cases of basaloid carcinoma were studied by means of immunohistochemistry and flow cytometry. Some immunohistochemical markers, such as epithelial membrane antigen, carcinoembrionic antigen, and keratins, as well as the lectin Ulex europaeus agglutinin I stained basaloid carcinoma and were negative for basal cell carcinoma. In contrast, the monoclonal antibody Ber-EP4 seems to be a good marker for perianal basal cell carcinoma and useful in differentiating it from basaloid carcinoma of the anus. Basaloid carcinomas are associated with a significantly higher S-phase fraction than are perianal basal cell carcinomas (p < 0.01).