Metabolomics Highlights Different Life History Strategies of White and Brown Rot Wood-Degrading Fungi.

White and brown rot fungi efficiently deconstruct lignocellulose in wood, Earth's largest pool of aboveground biotic carbon and an important natural resource. Despite its vital importance, little is known about the metabolomic signatures among fungal species and nutritional modes (rot types). In this study, we used GC-MS metabolomics in solid wood substrates (in planta) to compare brown rot fungi (Rhodonia placenta and Gloeophylum trabeum) and white rot fungi (Trametes versicolor and Pleurotus ostreatus) at two decay stages (earlier and later), finding identifiable patterns for brown rot fungi at later decay stages. These patterns occurred in highly reducing environments that were not observed in white rot fungi. Metabolomes measured among the two white rot fungi were notably different, but we found a potential biomarker compound, galactitol, that was characteristic to white rot taxa. In addition, we found that white rot fungi were more efficient at catabolizing phenolic compounds that were originally present in wood. Collectively, white rot fungi were characterized by measured sugar release relative to higher carbohydrate solubilization by brown rot fungi, a distinction in soluble sugar availability that might shape success in the face of "cheater" competitors. This need to protect excess free sugars may explain the differentially high brown rot fungal production of pyranones and furanones, likely linked to an expansion of polyketide synthase genes. IMPORTANCE Despite the ecological and economic importance of wood-degrading fungi, little is known about the array of metabolites that fungi produce during wood decomposition. This study provides an in-depth insight into the wood decomposition process by analyzing and comparing the changes of >100 compounds produced by fungi with metabolic distinct nutritional modes (white and brown rot fungi) at different decay stages. We found a unique pattern of metabolites that correlated well with brown rot (carbohydrate selective mode) in later decay. These compounds were in line with some of the physiochemical and genetic features previously seen in these fungi such as a faster sugar release, lower pH, and the expansion of polyketide-synthase genes compared to white rot fungi (lignin-degrading mode). This study provides spatiotemporally resolved mechanism insights as well as critical groundwork that will be valuable for studies in basic biology and ecology, as well as applied biomass deconstruction and bioremediation.

Active surveillance as a successful management strategy for patients with clinical stage I germ cell testicular cancer.

BACKGROUND: Cancer-specific survival for patients with clinical stage I (CSI) germ cell testicular cancer (GCTC) is outstanding after inguinal orchidectomy regardless the treatment utilized. This study evaluated whether active surveillance (AS) of such patients yielded similar health outcomes to other therapeutic strategies such as adjuvant chemotherapy, radiotherapy or primary retroperitoneal lymphadenectomy as described in the literature. PATIENTS AND METHODS: Patients with CSI GCTC were screened between January 2012 and December 2016. Patients had previously undergone inguinal orchidectomy as the primary treatment and chosen AS as their preferred management strategy after receiving information about all available strategies. RESULTS: Out of 91 patients screened, 82 patients selected AS as their preferred management strategy. Relapse rate in the overall population was 20% (95% CI 12-30) and median time to relapse was 11.5 months (range 1.0-35.0). In patients with seminomatous tumors, relapse rate decreased to 13% and median time to relapse was 13 months; whereas in patients with non-seminomatous tumors, relapse rate was 33% (IA) or 29% (IB) and median time to relapse was 12 months in stage IA and 4.5 months in stage IB patients. All relapses were rescued with three or four cycles of chemotherapy and two also required a retroperitoneal lymphadenectomy. All patients are currently alive and free of disease. CONCLUSIONS: The clinical outcomes of patients with CSI GCTC managed by AS in this series were excellent. This strategy limited the administration of active treatments specifically to the minority of patients who relapsed without compromising performance.

Molecular dynamics simulation of complex particles in three dimensions and the study of friction due to nonconvexity.

We investigate the macroscopic properties of frictionless nonconvex particles using molecular dynamics. The calculations are based on a simple and efficient method to simulate complex-shaped interacting bodies. The particle shape is represented by Minkowski operators. A multicontact time-continuous interaction between bodies is derived using simple concepts of computational geometry. Three-dimensional simulations of hopper flow show that the nonconvexity of the particles strongly affects the jamming on granular flow. Also the model allows the representation of complex bodies with rough surfaces as in friction studies and the reproduction of a wide range of friction and dilatancy angles as in true triaxial tests.