Joint estimation of crown of thorns (Acanthaster planci) densities on the Great Barrier Reef.

Crown-of-thorns starfish (CoTS; Acanthaster spp.) are an outbreaking pest among many Indo-Pacific coral reefs that cause substantial ecological and economic damage. Despite ongoing CoTS research, there remain critical gaps in observing CoTS populations and accurately estimating their numbers, greatly limiting understanding of the causes and sources of CoTS outbreaks. Here we address two of these gaps by (1) estimating the detectability of adult CoTS on typical underwater visual count (UVC) surveys using covariates and (2) inter-calibrating multiple data sources to estimate CoTS densities within the Cairns sector of the Great Barrier Reef (GBR). We find that, on average, CoTS detectability is high at 0.82 [0.77, 0.87] (median highest posterior density (HPD) and [95% uncertainty intervals]), with CoTS disc width having the greatest influence on detection. Integrating this information with coincident surveys from alternative sampling programs, we estimate CoTS densities in the Cairns sector of the GBR averaged 44 [41, 48] adults per hectare in 2014.

Detection of viral RNA from paraffin-embedded tissues after prolonged formalin fixation.

BACKGROUND: Isolating amplifiable RNA from formalin-fixed, paraffin-embedded (FFPE) tissues is more difficult than isolating DNA because of RNases, chemical modification of the RNA, and cross-linking of nucleic acids and proteins. Tissues containing infectious disease agents that require biosafety level (BSL)-3 and -4 necessitate fixation times of 21 and 30 days, respectively. OBJECTIVE: To improve procedures for extracting RNA from these FFPE tissues and detect the RNA with the more sensitive TaqManbased reverse transcriptase (RT)-PCR. STUDY DESIGN: Through a single modification of a commercially available kit, we were able to extract amplifiable RNA and detect West Nile virus (WNV), Marburg virus (MARV), and Ebola virus (EBOV)-infected tissues using TaqMan assays. RESULTS: Formalin fixation results in an approximately 2log(10) reduction in detection limit when compared to fresh tissues. Increasing proteinase K digestion (24h) improved extraction of amplifiable RNA from FFPE tissues. The TaqMan results were comparable to more traditional detection results such as virus isolation. CONCLUSION: This improved extraction procedure for obtaining RNA combined with the TaqMan RT-PCR assays permit retrospective and prospective studies on FFPE tissues infected with BSL-3 and -4 pathogens.

Universal red blood cells--enzymatic conversion of blood group A and B antigens.

Accidental transfusion of ABO-incompatible red blood cells (RBCs) is a leading cause of fatal transfusion reactions. To prevent this and to create a universal blood supply, the idea of converting blood group A and B antigens to H using specific exo-glycosidases capable of removing the immunodominant sugar residues was pioneered by Goldstein and colleagues at the New York Blood Center in the early 1980s. Conversion of group B RBCs to O was initially carried out with alpha-galactosidase extracted from coffee beans. These enzyme-converted O (ECO) RBCs appeared to survive normally in all recipients independent of blood group. The clinical trials moved from small infusions to single RBC units and finally multiple and repeated transfusions. A successful phase II trial utilizing recombinant enzyme was reported by Kruskall and colleagues in 2000. Enzymatic conversion of group A RBCs has lagged behind due to lack of appropriate glycosidases and the more complex nature of A antigens. Identification of novel bacterial glycosidases with improved kinetic properties and specificities for the A and B antigens has greatly advanced the field. Conversion of group A RBCs can be achieved with improved glycosidases and the conversion conditions for both A and B antigens optimized to use more cost-efficient quantities of enzymes and gentler conditions including neutral pH and short incubation times at room temperature. Of the different strategies envisioned to create a universal blood supply, the ECO concept is the only one, for which human clinical trials have been performed. This paper discusses some biochemical and clinical aspects of this developing technology.