Black Aortic Valve: Incidental Finding of Alkaptonuria.

 Alkaptonuria is a rare autosomal recessive genetic disorder of tyrosine metabolism, which results in accumulation of homogentisic acid in various tissues, including the cardiovascular system.  We report on a 64-year-old man with mixed aortic valve disease who underwent conventional aortic valve replacement. Intraoperative aortotomy revealed black pigmentation of the intima of the ascending aorta and the aortic valve was observed with thickened and calcified dark black leaflets.

Contrast-Enhanced Ultrasonography as a Novel Method for the Dynamic Visualization of Blood Flow and Fiber Blockage in Dialyzers: A Feasibility Study.

The capillary dialyzer represents the central element of the extracorporeal blood circuit of a therapy system for hemodialysis. The aim of this study was to assess the blood-flow characteristics of dialyzers with the help of modern ultrasound techniques. Five brand-new dialyzers (FX80 classix, Fresenius Medical Care, Bad Homburg, Germany) and five dialyzers after a dialysis session were analyzed by different ultrasound techniques to detect functional and structural changes.

Pericardiectomy for Constrictive Pericarditis: An Institution's 21 Years Experience.

Background: The aim of this retrospective study was to evaluate our experience with the surgical pericardiectomy procedure for patients suffering from isolated severe constrictive pericarditis.

Methods: From 1995 to 2016, 39 patients underwent isolated pericardiectomy for constrictive pericarditis. Fifteen patients were excluded because of concomitant surgery.

Genetic diversity of calcareous grassland plant species depends on historical landscape configuration.

Background: Habitat fragmentation is considered to be a main reason for decreasing genetic diversity of plant species. However, the results of many fragmentation studies are inconsistent. This may be due to the influence of habitat conditions, having an indirect effect on genetic variation via reproduction.

Living in isolation - population structure, reproduction, and genetic variation of the endangered plant species Dianthus gratianopolitanus (Cheddar pink).

The endangered plant species Dianthus gratianopolitanus exhibits a highly fragmented distribution range comprising many isolated populations. Based upon this pattern of distribution, we selected a study region in Switzerland with a lower magnitude of isolation (Swiss Jura) and another study region in Germany with a higher degree of isolation (Franconian Jura). In each region, we chose ten populations to analyze population structure, reproduction, and genetic variation in a comparative approach.