Diploids in the Cryptococcus neoformans Serotype A Population Homozygous for the α Mating Type Originate via Unisexual Mating

The ubiquitous environmental human pathogen Cryptococcus neoformans is traditionally considered a haploid fungus with a bipolar mating system. In nature, the α mating type is overwhelmingly predominant over a. How genetic diversity is generated and maintained by this heterothallic fungus in a largely unisexual α population is unclear. Recently it was discovered that C. neoformans can undergo same-sex mating under laboratory conditions generating both diploid intermediates and haploid recombinant progeny. Same-sex mating (α-α) also occurs in nature as evidenced by the existence of natural diploid αADα hybrids that arose by fusion between two α cells of different serotypes (A and D). How significantly this novel sexual style contributes to genetic diversity of the Cryptococcus population was unknown. In this study, ∼500 natural C. neoformans isolates were tested for ploidy and close to 8% were found to be diploid by fluorescence flow cytometry analysis. The majority of these diploids were serotype A isolates with two copies of the α MAT locus allele. Among those, several are intra-varietal allodiploid hybrids produced by fusion of two genetically distinct α cells through same-sex mating. The majority, however, are autodiploids that harbor two seemingly identical copies of the genome and arose via either endoreplication or clonal mating. The diploids identified were isolated from different geographic locations and varied genotypically and phenotypically, indicating independent non-clonal origins. The present study demonstrates that unisexual mating produces diploid isolates of C. neoformans in nature, giving rise to populations of hybrids and mixed ploidy. Our findings underscore the importance of same-sex mating in shaping the current population structure of this important human pathogenic fungus, with implications for mechanisms of selfing and inbreeding in other microbial pathogens

The International E-vita Open Registry: data sets of 274 patients.

After the introduction of the hybrid stent-graft "E-vita-open" by the Essen group in 1/2005 for one stage repair of complex thoracic aortic disease, the International E-vita open Registry was founded in 2008 to study the principles of this treatment algorithm and to control reported favorable single center results on a large patient data set basis up to six years after the first clinical implant. METHODS: Retrospective data work-up after prospective data acquisition was achieved by institution of the International E-vita open Registry with anonymous registration and calculation at Essen University Hospital. From January 2005 to December 2010, 274 patients (mean age 60; 74% males) with complex aortic disease, 190 with aortic dissection (88 acute (AAD), 102 chronic aortic dissection (CAD), and 84 with complex thoracic aortic aneurysm (TAA) were included in the studied. RESULTS: Eighty-one out of 274 (30%) patients underwent emergency surgery. Stent-graft deployment and arch replacement (238 total, 36 subtotal) was performed under selective antegrade cerebral perfusion (75 min mean). Cardiopulmonary bypass (CPB) and cardiac arrest times were mean 235 and 134 minutes, respectively. In-hospital mortality was 15% (40/274), 18% for AAD, 13% for CAD, and 14% for TAA. New strokes were observed in 6% (16/274), spinal cord injury in 8% (22/274). The false lumen (FL) was evaluated throughout the first hospital stay and at a median follow up time of 59 months after surgery. From the first follow up CT-examination to the last, thoracic complete FL thrombosis increased from 83% to 93% in AAD, from 72% to 92% in CAD. Full exclusion of the aneurysmal disease was achieved in 77% (61/79) during the primary hospital stay. CONCLUSION: Favorable single center results could be confirmed by an International community of cardiac surgical centers in regard to hospital mortality and morbidity, as well as a low postoperative complication rate and exclusion of false lumen in aortic dissectio

Sutureless Aortic Valve Replacement International Registry (SU-AVR-IR): design and rationale from the International Valvular Surgery Study Group (IVSSG)

Sutureless aortic valve replacement (SU-AVR) is an innovative approach which shortens cardiopulmonary bypass and cross-clamp durations and may facilitate minimally invasive approach. Evidence outlining its safety, efficacy, hemodynamic profile and potential complications is replete with small-volume observational studies and few comparative publications.status: publishe

Sutureless versus conventional bioprostheses for aortic valve replacement in severe symptomatic aortic valve stenosis

Objective: Sutureless aortic valves are a novel option for aortic valve replacement. We sought to demonstrate noninferiority of sutureless versus standard bioprostheses in severe symptomatic aortic stenosis. Methods: The Perceval Sutureless Implant Versus Standard-Aortic Valve Replacement is a prospective, randomized, adaptive, open-label trial. Patients were randomized (March 2016 to September 2018) to aortic valve replacement with a sutureless or stented valve using conventional or minimally invasive approach. Primary outcome was freedom from major adverse cerebral and cardiovascular events (composite of all-cause death, myocardial infarction, stroke, or valve reintervention) at 1 year. Results: At 47 centers (12 countries), 910 patients were randomized to sutureless (n = 453) or conventional stented (n = 457) valves; mean ages were 75.4 ± 5.6 and 75.0 ± 6.1 years, and 50.1% and 44.9% were female, respectively. Mean ± standard deviation Society of Thoracic Surgeons scores were 2.4 ± 1.7 and 2.1 ± 1.3, and a ministernotomy approach was used in 50.4% and 47.3%, respectively. Concomitant procedures were performed with similar rates in both groups. Noninferiority was demonstrated for major adverse cerebral and cardiovascular events at 1 year, whereas aortic valve hemodynamics improved equally in both groups. Use of sutureless valves significantly reduced surgical times (mean extracorporeal circulation times: 71.0 ± 34.1 minutes vs 87.8 ± 33.9 minutes; mean crossclamp times: 48.5 ± 24.7 vs 65.2 ± 23.6; both P <.0001), but resulted in a higher rate of pacemaker implantation (11.1% vs 3.6% at 1 year). Incidences of perivalvular and central leak were similar. Conclusions: Sutureless valves were noninferior to stented valves with respect to major adverse cerebral and cardiovascular events at 1 year in patients undergoing aortic valve replacement (alone or with coronary artery bypass grafting). This suggests that sutureless valves should be considered as part of a comprehensive valve program