Cryptococcus neoformans infective endocarditis after lung transplantation: a case report and review of the literature.

Cryptococcus neoformans infective endocarditis is rarely reported. In this report, we present a case of infective endocarditis secondary to Cryptococcus neoformans in a lung-transplant recipient and review the relevant literature. A 65-year-old man was hospitalized with hypoxemic respiratory failure and underwent left-sided single lung transplantation. In the setting of worsening hypoxemia, blood cultures were drawn, which grew C. neoformans. Lumbar puncture was performed, and CSF PCR was also positive for Cryptococcus. Further exposure history revealed that he had raised chickens while living in Peru. Transesophageal echocardiography showed an aortic valve vegetation, and he was diagnosed with cryptococcal infective endocarditis. He received liposomal amphotericin B and flucytosine for two weeks and was later transitioned to fluconazole. This case highlights the need for thorough social history prior to lung transplantation, as pulmonary colonization with C. neoformans may result in infective endocarditis after immunosuppression.

Titanium dioxide nanoparticle exposure alters metabolic homeostasis in a cell culture model of the intestinal epithelium and Drosophila melanogaster.

Nanosized titanium dioxide (TiO2) is a common additive in food and cosmetic products. The goal of this study was to investigate if TiO2 nanoparticles affect intestinal epithelial tissues, normal intestinal function, or metabolic homeostasis using in vitro and in vivo methods. An in vitro model of intestinal epithelial tissue was created by seeding co-cultures of Caco-2 and HT29-MTX cells on a Transwell permeable support. These experiments were repeated with monolayers that had been cultured with the beneficial commensal bacteria Lactobacillus rhamnosus GG (L. rhamnosus). Glucose uptake and transport in the presence of TiO2 nanoparticles was assessed using fluorescent glucose analog 2-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-2-deoxyglucose (2-NBDG). When the cell monolayers were exposed to physiologically relevant doses of TiO2, a statistically significant reduction in glucose transport was observed. These differences in glucose absorption were eliminated in the presence of beneficial bacteria. The decrease in glucose absorption was caused by damage to intestinal microvilli, which decreased the surface area available for absorption. Damage to microvilli was ameliorated in the presence of L. rhamnosus. Complimentary studies in Drosophila melanogaster showed that TiO2 ingestion resulted in decreased body size and glucose content. The results suggest that TiO2 nanoparticles alter glucose transport across the intestinal epithelium, and that TiO2 nanoparticle ingestion may have physiological consequences.