Unsaturated Fatty Acids Are Decreased in Aβ Plaques in Alzheimer's Disease.

Alzheimer's disease (AD) is characterized by the accumulation of amyloid-beta (Aβ) plaques in the brain, contributing to neurodegeneration. This study investigates lipid alterations within these plaques using a novel, label-free, multimodal approach. Combining infrared (IR) imaging, machine learning, laser microdissection (LMD), and flow injection analysis mass spectrometry (FIA-MS), we provide the first comprehensive lipidomic analysis of chemically unaltered Aβ plaques in post-mortem human AD brain tissue.

Abstraction-based segmental simulation of reaction networks using adaptive memoization.

Background:  Stochastic models are commonly employed in the system and synthetic biology to study the effects of stochastic fluctuations emanating from reactions involving species with low copy-numbers. Many important models feature complex dynamics, involving a state-space explosion, stiffness, and multimodality, that complicate the quantitative analysis needed to understand their stochastic behavior. Direct numerical analysis of such models is typically not feasible and generating many simulation runs that adequately approximate the model's dynamics may take a prohibitively long time.

Antibiotic profiling of wild-type bacilli led to the discovery of new lanthipeptide subtilin-producing Bacillus spizizenii strains whose 16S rDNA sequences differ from the B. spizizenii typing strain.

Two dozen field-collected Bacillus and a dozen Bacillus spizizenii wild-type strains from strain collections were selected on the basis of their antagonistic properties against the Gram-positive strain Micrococcus luteus. Based on their genetic and antibiotic profiles, they were characterized (subtilin encoding spaS gene sequences, mass spectrometric, and quantitative-reversed phase liquid chromatographic analyses, as well as the presence of the lanthionine cyclase protein SpaC by western blotting), seven novel producers of the lanthipeptide subtilin. Phylogenetic analyses of the subtilin-producing wild-type strains based on their 16S rRNA sequences showed that all seven strains could be classified as B.

Glycan degradation promotes macroautophagy.

Macroautophagy promotes cellular homeostasis by delivering cytoplasmic constituents to lysosomes for degradation [Mizushima, 20, 521-527 (2018)]. However, while most studies have focused on the mechanisms of protein degradation during this process, we report here that macroautophagy also depends on glycan degradation via the glycosidase, α-l-fucosidase 1 (FUCA1), which removes fucose from glycans. We show that cells lacking FUCA1 accumulate lysosomal glycans, which is associated with impaired autophagic flux.

Pre- and post-transplant bacterial infections in liver transplant recipients.

Background: Early (<1 month) bacterial infection after liver transplant is a major cause of morbidity and mortality among liver transplant recipients. We investigated the impact of pre-transplant bacterial infection on early post-transplant bacterial infection incidence and outcomes.

Methods: A retrospective cohort study identified all patients who underwent liver transplantation between January 1, 2011, and December 31, 2012, at a single tertiary center in the United States.