Liver Transplantation for Acute Liver Failure due to Yellow Fever: A Case Report.

Yellow fever is a noncontagious disease caused by an arbovirus in the Flaviviridae family. It is an endemic disease in the tropical forests of Africa and South America, with the mosquito as a vector. Approximately half of those infected will be asymptomatic, while 15% will develop the severe/malignant form of the disease that includes renal and hepatic failure, bleeding, and neurological impairment as the principal symptoms. The lethality of the severe form reaches up to 70%. The objective of this study was to report on the case of a patient who was transferred to the hepatobiliary unit of our service due to acute liver failure due to yellow fever. He was treated with liver transplantation. The patient progressed satisfactorily, being discharged from the intensive care unit in 10 days and discharged from the hospital within 19 days after transplantation. Despite the encouraging result of our team, this has not been applied to other centers that have also performed this modality of treatment; therefore, the question remains as to whether and when to recommend liver transplantation for treatment of severe yellow fever.

Evidence for direct electron transfer by a gram-positive bacterium isolated from a microbial fuel cell.

Despite their importance in iron redox cycles and bioenergy production, the underlying physiological, genetic, and biochemical mechanisms of extracellular electron transfer by Gram-positive bacteria remain insufficiently understood. In this work, we investigated respiration by Thermincola potens strain JR, a Gram-positive isolate obtained from the anode surface of a microbial fuel cell, using insoluble electron acceptors. We found no evidence that soluble redox-active components were secreted into the surrounding medium on the basis of physiological experiments and cyclic voltammetry measurements. Confocal microscopy revealed highly stratified biofilms in which cells contacting the electrode surface were disproportionately viable relative to the rest of the biofilm. Furthermore, there was no correlation between biofilm thickness and power production, suggesting that cells in contact with the electrode were primarily responsible for current generation. These data, along with cryo-electron microscopy experiments, support contact-dependent electron transfer by T. potens strain JR from the cell membrane across the 37-nm cell envelope to the cell surface. Furthermore, we present physiological and genomic evidence that c-type cytochromes play a role in charge transfer across the Gram-positive bacterial cell envelope during metal reduction.