Villumsenmooney1263

Exploring features of wood anatomy associated with fire scars found on fossil tree trunks is likely to increase our knowledge of the environmental and ecological processes that occurred in ancient forests and of the role of fire as an evolutionary force. In Petrified Forest National Park, Arizona, where Late Triassic fossil trees are exposed, we found 13 examples of fossil logs with external features resembling modern fire scars. One specimen with the unambiguous external features of a fire scar was collected for analysis of its fossilized wood. A light-colored band composed of compressed and distorted tracheids was associated with the scarring event. Cell lumen diameter and cell wall thickness in the pre-scarring fossilized wood show a response similar to that described in modern trees experiencing drought conditions. Tracheids in the post-scarring wood are initially smaller, and then become larger than average following a recovery period, as is often observed in modern conifers following fire. The responses in external morphology and wood anatomy to drought and fire were similar to those of some modern trees and support the view that some forests may have experienced conditions favoring the evolution of fire-adapted traits for more than 200 million years.The influenza virus fusion process, whereby the virus fuses its envelope with the host endosome membrane to release the genetic material, takes place in the acidic late endosome environment. Acidification triggers a large conformational change in the fusion protein, hemagglutinin (HA), which enables the insertion of the N-terminal region of the HA2 subunit, known as the fusion peptide, into the membrane of the host endosome. However, the mechanism by which pH modulates the molecular properties of the fusion peptide remains unclear. To answer this question, we performed the first constant-pH molecular dynamics simulations of the influenza fusion peptide in a membrane, extending for 40 µs of aggregated time. The simulations were combined with spectroscopic data, which showed that the peptide is twofold more active in promoting lipid mixing of model membranes at pH 5 than at pH 7.4. The realistic treatment of protonation introduced by the constant-pH molecular dynamics simulations revealed that low pH stabilizes a vertical membrane-spanning conformation and leads to more frequent contacts between the fusion peptide and the lipid headgroups, which may explain the increase in activity. The study also revealed that the N-terminal region is determinant for the peptide's effect on the membrane.Miniaturization and integration of optical tweezers are attractive. Optical fiber-based trapping systems allow optical traps to be realized in miniature systems, but the optical traps in these systems lack reliability or mobility. Here, we present the all-fiber modular optical tweezers (AFMOTs), in which an optical trap can be reliably created and freely moved on a sample substrate. Two inclined optical fibers are permanently fixed to a common board, rendering a modular system where fiber alignments are maintained over months. The freely movable optical trap allows particles to be trapped in their native locations. As a demonstration, we applied AFMOTs to trap and deform freely floating individual cells. By the cell mechanical responses, we differentiated the nontumorigenic breast epithelial cell line (MCF10A) from its cancerous PTEN mutants (MCF10 PTEN-/-). To further expand the functionalities, three modalities of AFMOTs are demonstrated by changing the types of fibers for both the optical trap creation and particle position detection. As a miniature and modular system that creates a reliable and mobile optical trap, AFMOTs can find potential applications ranging from point-of-care diagnostics to education, as well as helping transition the optical trapping technology from the research lab to the field.Excessive alcohol consumption leads to overproduction of urates and renal function plays a critical role in serum uric acid levels. We aimed to assess associations of hyperuricemia in patients with alcohol use disorder (AUD) and comparable Glomerular Filtration Rate (GFR). A total of 686 patients undergoing treatment for AUD between 2013 and 2017 were eligible (77% men); age at admission was 47 years [interquartile range (IQR), 40-53 years], age of onset of alcohol consumption was 16 years [IQR, 16-18 years] and the amount of alcohol consumed was 160 g/day [IQR, 120-240 g/day]. Body Mass Index was 24.7 kg/m2 [IQR, 21.9-28.4 kg/m2], eGFR was 105 mL/min/1.73 m2 [IQR, 95.7-113.0 mL], 9.7% had metabolic syndrome and 23% had advanced liver fibrosis (FIB-4 > 3.25). Prevalence of hyperuricemia was 12.5%. The eGFR-adjusted multivariate analysis showed that relative to patients with GGT ≤ 50, those with GGT between 51 and 300 U/L and those with GGT > 300 U/L were 4.31 (95% CI 1.62-11.46) and 10.3 (95% CI 3.50-29.90) times more likely to have hyperuricemia, respectively. Our data shows that hyperuricemia in the context of AUD is strongly associated with serum GGT levels and suggest an increased cardio-metabolic risk in this population.The pachychoroid disease spectrum encompasses seven major retinal conditions including central serous chorioretinopathy (CSC), polypoidal choroidal vasculopathy (PCV), and pachychoroid neovasculopathy or type I macular neovascularisation (MNV) secondary to chronic persistent thickening and dysfunction of the choroidal vasculature. Drusen are focal yellow-white deposits of extracellular debris, which consist of complement proteins, esterified and nonesterified cholesterol, apolipoproteins, carbohydrates, and trace elements, above the retinal pigment epithelium (RPE) or between the RPE and Bruch's membrane. Although drusen are an essential disease precursor of advanced age-related macular degeneration (AMD), a new entity "pachydrusen" has been identified to be associated with some of the enitites that constitute the pachychoroid spectrum. Selleck GDC-1971 It remains to be determined what the exact differences are between soft drusen, pseudodrusen, and pachydrusen in terms of phenotype, genotype, and pathogenesis. Improving our knowledge in these areas will inevitably improve our understanding of their clinical significance especially as in disease prediction in AMD and the pachychroid spectrum disorders.