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Mature tropical urban trees are susceptible to root and trunk rot caused by pathogenic fungi. A metagenomic survey of such fungi was carried out on 210 soil and tissue samples collected from 134 trees of 14 common species in Singapore. Furthermore, 121 fruiting bodies were collected and barcoded. Out of the 22,067 OTUs (operational taxonomic units) identified, 10,646 OTUs had annotation information, and most were either ascomycetes (63.4%) or basidiomycetes (22.5%). Based on their detection in the diseased tissues and surrounding soils and/or the presence of fruiting bodies, fourteen basidiomycetes (nine Polyporales, four Hymenochaetales, one Boletales) and three ascomycetes (three species of Scytalidium) were strongly associated with the diseased trees. Fulvifomes siamensis affected the largest number of tree species surveyed. The association of three fungi was further supported by in vitro wood decay studies. Genetic heterogeneity was common in the diseased tissues and fruiting bodies (Ganoderma species especially). This survey identified the common pathogenic fungi of tropical urban trees and laid the foundation for early diagnosis and targeted mitigation efforts. It also illustrated the complexity of fungal ecology and pathogenicity.

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The major cause of systolic decrease in contrast enhancement is periodic bubble compression (as opposed to bubble destruction) induced by high systolic pressures. The minor progressive decrease in end-diastolic videointensity reflects the degree of instability of Albunex microbubbles under left ventricular pressures. However, the clinical impact of these destructive effects is likely to be only minor because of the rapid transit of microbubbles through the left heart chambers and myocardial microcirculation.

Background Patients undergoing transcatheter aortic valve replacement can experience severe perioperative complications leading to hemodynamic instability and death. Venoarterial extracorporeal membrane oxygenation can be used to provide cardiorespiratory support during this time. Methods From 2012 to 2015, of 247 patients who underwent transcatheter aortic valve replacement, 6 (2.42%) required extracorporeal membrane oxygenation support. Their mean age was 82 ± 7.4 years, mean Society of Thoracic Surgeons score was 9.4 ± 6.6, and mean aortic gradient was 28.3 ± 12 mm Hg. Rescue extracorporeal membrane oxygenation was required for hemodynamic instability due to ventricular fibrillation ( n = 1), respiratory failure ( n = 1), left ventricular wall rupture ( n = 2), and aortic annulus rupture ( n = 1). In one patient, prophylactic extracorporeal membrane oxygenation was required due to advanced heart failure. Additional procedures included valve-in-valve implantation ( n = 1), conversion to an open procedure ( n = 3), and intraaortic balloon pump insertion ( n = 1). Results The median hospital stay was 20 days. There were 2 hospital deaths in patients whose hospital course was complicated by left ventricular wall rupture or aortic annulus rupture with resulting tamponade. Among the 4 survivors, one required continuous ventilator support following discharge, and 3 experienced no major complications during the first month after discharge. Conclusions Extracorporeal membrane oxygenation can be considered a viable option for high-risk patients undergoing transcatheter aortic valve replacement and those who develop cardiac complications following this procedure and require cardiorespiratory support.