Calcifying epithelial odontogenic tumour of the maxilla: a case report with respect to immunohistochemical findings

Calcifying epithelial odontogenic tumour (Pindborg tumour) is a rare benign neoplasm with a poorly understood histogenesis. This report describes a single case of a maxillary calcifying epithelial odontogenic tumour including immunohistochemical analysis. The vast majority of tumour cells were positive for CK5/6 and p63. Furthermore, basal cells also displayed moderate reaction for vimentin and strong membranous positivity for podoplanin. Interestingly, the tumour invaded the dental pulp of the partially disintegrated tooth root. While the tumour showed focal connection with the superficial gingival epithelium and revealed intercellular bridges, the findings of this case study seem to support the suggestion of an epithelial origin of a calcifying epithelial odontogenic tumour derived from the dental lamina.     

Controlled release of chlorhexidine antiseptic from microporous amorphous silica applied in open porosity of an implant surface

Amorphous microporous silica (AMS) serving as a reservoir for controlled release of a bioactive agent was applied in the open porosity of a titanium coating on a Ti-6Al-4V metal substrate. The pores of the AMS emptied by calcination were loaded with chlorhexidine diacetate (CHX) via incipient wetness impregnation with CHX solution, followed by solvent evaporation. Using this CHX loaded AMS system on titanium substrate sustained release of CHX into physiological medium was obtained over a 10 day-period. CHX released from the AMS coating was demonstrated to be effective in killing planktonic cultures of the human pathogens Candida albicans and Staphylococcus epidermidis. This surface modification of titanium bodies with AMS controlled release functionality for a bioactive compound potentially can be applied on dental and orthopaedic implants to abate implant-associated microbial infection.     

Monitoring drug efficacy against gastrointestinal nematodes when faecal egg counts are low: do the analytic sensitivity and the formula matter?

The faecal egg count reduction test (FECR) is the recommended technique to monitor anthelmintic drug efficacy in livestock. However, results are often inconclusive due to the low analytic sensitivity of the diagnostic technique or the conflict in results from FECR formulae. A novel experimental set-up was, therefore, used to compare the impact of analytic sensitivity and formulae on FECR results. Four McMaster techniques (analytic sensitivities 50, 33.3, 15 and 10) and a FLOTAC technique (analytic sensitivity ~ 1) were used on faecal samples of 30 calves with a FEC of less than 200 eggs per gram. True drug efficacies of 70%, 80% and 90% were experimentally mimicked by comparing FEC before and after dilution (3:10, 2:10 and 1:10, respectively). The FECR was summarized using group (FECR(1)) and individual (FECR(2)) based formulae. There was a significant increase in precision of FECR when the analytic sensitivity increased (p < 0.0001). The precision also depended on the formula used, FECR(1) (p < 0.05) resulting in more precise FECR compared to FECR(2). The accuracy of the FECR differed marginally between the two formulae (p = 0.06), FECR(1) being more accurate. In conclusion, the present study describes a novel methodology to compare techniques for the precision and the accuracy of their FECR results. The results underscored that techniques with high analytic sensitivity will improve the interpretation of FECR in animal populations where baseline FEC are low. They also point out that the precision of individual-based formulae is affected by the analytic sensitivity.     

An extremely rare case of delusional parasitosis in a chronic hepatitis C patient during pegylated interferon alpha-2b and ribavirin treatment

During treatment of chronic hepatitis C patients with interferon and ribavirin, a lot of side effects are described. Twenty-three percent to 44% of patients develop depression. A minority of patients evolve to psychosis. To the best of our knowledge, no cases of psychogenic parasitosis occurring during interferon therapy have been described in the literature. We present a 49-year-old woman who developed a delusional parasitosis during treatment with pegylated interferon alpha-2b weekly and ribavirin. She complained of seeing parasites and the larvae of fleas in her stools. This could not be confirmed by any technical examination. All the complaints disappeared after stopping pegylated interferon alpha-2b and reappeared after restarting it. She had a complete sustained viral response.