Introduction: Brain cholesterol relies on de novo biosynthesis and is crucial for brain development. Cholesterol synthesis is a complex series of reactions that involves more than twenty enzymes to reach the final product and generates a large number of intermediate sterols along two alternate pathways. This is a highly regulated and oxygen-dependent process, and thus sensitive to hypoxia.
View Article and Find Full Text PDFPreclinical models of addictive drugs have been developed for decades to model aspects of the clinical experience in substance use disorders (SUDs). These include passive exposure as well as volitional intake models across addictive drugs and have been utilized to also measure withdrawal symptomatology and potential neurobehavioral mechanisms underlying relapse to drug seeking or taking. There are a number of Food and Drug Administration (FDA)-approved medications for SUDs, however, many demonstrate low clinical efficacy as well as potential sex differences, and we also note gaps in the continuum of care for certain aspects of clinical experiences in individuals who use drugs.
View Article and Find Full Text PDFStatins are known to be anti-inflammatory, but the mechanism remains poorly understood. Here, we show that macrophages, either treated with statin in vitro or from statin-treated mice, have reduced cholesterol levels and higher expression of , a H3K27me3 demethylase. We provide evidence that lowering cholesterol levels in macrophages suppresses the adenosine triphosphate (ATP) synthase in the inner mitochondrial membrane and changes the proton gradient in the mitochondria.
View Article and Find Full Text PDFIntroduction: Chemotherapy-induced cognitive impairment colloquially referred to as chemobrain is a poorly understood phenomenon affecting a highly variable proportion of patients with breast cancer. Here we investigate the association between anxiety and despair-like behaviors in mice treated with cyclophosphamide, methotrexate, and fluorouracil (CMF) along with host histological, proteomic, gene expression, and gut microbial responses.
Methods: Forced swim and sociability tests were used to evaluate depression and despair-like behaviors.
Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) exist on a spectrum of autoimmune conditions which cause epidermal detachment and keratinocyte necrosis. Due to the rare incidence of these conditions, a dramatic heterogeneity in treatment algorithms exists. To better appreciate pharmacologic immunosuppressive therapies' impact on survival, the authors queried a multi-institutional data network.
View Article and Find Full Text PDFGlioblastoma (GBM) is an aggressive adult brain cancer with few treatment options due in part to the challenges of identifying brain-penetrant drugs. Here, we investigated the mechanism of MM0299, a tetracyclic dicarboximide with anti-glioblastoma activity. MM0299 inhibits lanosterol synthase (LSS) and diverts sterol flux away from cholesterol into a "shunt" pathway that culminates in 24(S),25-epoxycholesterol (EPC).
View Article and Find Full Text PDFMost of the cholesterol in the plasma membranes (PMs) of animal cells is sequestered through interactions with phospholipids and transmembrane domains of proteins. However, as cholesterol concentration rises above the PM's sequestration capacity, a new pool of cholesterol, called accessible cholesterol, emerges. The transport of accessible cholesterol between the PM and the endoplasmic reticulum (ER) is critical to maintain cholesterol homeostasis.
View Article and Find Full Text PDFCells sense stress and initiate response pathways to maintain lipid and protein homeostasis. However, the interplay between these adaptive mechanisms is unclear. Herein, we demonstrate how imbalances in cytosolic protein homeostasis affect intracellular lipid surveillance.
View Article and Find Full Text PDFBackground: The purpose of this study was to assess gastric feeding intolerance for critically ill patients who received sustained neuromuscular blocker (NMB) pharmacotherapy.
Methods: Adult patients (>17 years of age) admitted to the trauma intensive care unit who received continuous intravenous NMB pharmacotherapy (rocuronium, cisatracurium, vecuronium, or pancuronium) for ≥48 h during continuous intragastric enteral nutrition (EN) were retrospectively evaluated. Gastric feeding intolerance was defined by initiation of a prokinetic agent (metoclopramide, erythromycin, or both) for an elevated gastric residual volume (GRV) >300 ml and with distention of the abdomen by physical examination, observation of regurgitation or emesis, temporary discontinuation of EN with low intermittent gastric suctioning, or initiation of parenteral nutrition (PN).
The environment outside the Earth's protective magnetosphere is a much more threatening and complex space environment. The dominant causes for radiation exposure, solar particle events and galactic cosmic rays, contain high-energy protons. In space, astronauts need healthy and highly functioning cognitive abilities, of which the hippocampus plays a key role.
View Article and Find Full Text PDF27-Hydroxycholesterol (27-HC) is the most abundant oxysterol that increases the risk of breast cancer progression. However, little is known about epigenetic regulation of 27-HC metabolism and its role in breast tumor initiation. Using genetic mouse mammary tumor and human breast cancer models, we showed here that the histone reader ZMYND8 was selectively expressed in breast cancer stem cells (BCSCs) and promoted epithelial-mesenchymal transition (EMT), BCSC maintenance and self-renewal, and oncogenic transformation through its epigenetic functions, leading to breast tumor initiation.
View Article and Find Full Text PDFImbalances in lipid homeostasis can have deleterious effects on health. Yet how cells sense metabolic demand due to lipid depletion and respond by increasing nutrient absorption remains unclear. Here we describe a mechanism for intracellular lipid surveillance in Caenorhabditis elegans that involves transcriptional inactivation of the nuclear hormone receptor NHR-49 through its cytosolic sequestration to endocytic vesicles via geranylgeranyl conjugation to the small G protein RAB-11.
View Article and Find Full Text PDF5-Fluorouracil (5-Fu) and leucovorin (LV) are often given in combination to treat colorectal cancer. 5-Fu/LV prevents cell proliferation by inhibiting thymidylate synthase, which catalyzes the conversion of deoxyuridine monophosphate to deoxythymidine monophosphate. While 5-Fu has been shown to cause cognitive impairment, the synergistic effect of 5-Fu with LV has not been fully explored.
View Article and Find Full Text PDFIn the past few years, breast cancer has become the most prevalent type of cancer. The majority of patients receive combinatorial chemotherapy treatments, which may result in increased risk of developing drug resistance, a reduced quality of life, and substantial side effects. Treatment modalities that could lessen the physical toll of standard treatments or act in synergy with chemotherapeutic treatments would benefit women worldwide.
View Article and Find Full Text PDFInflammation is considered one of the possible mechanisms behind long-term cognitive dysfunction persistent after chemotherapy treatment. The chemotherapy combination of cyclophosphamide, methotrexate, and fluorouracil (CMF) was one of the older methods of treating breast cancer patients. Decades later, these patients still report experiencing cognitive side effects.
View Article and Find Full Text PDFMatrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) has emerged as a major analytical platform for the determination and localization of lipid metabolites directly from tissue sections. Unlike analysis of lipid extracts, where lipid localizations are lost due to homogenization and/ or solvent extraction, MALDI-MSI analysis is capable of revealing spatial localization of metabolites while simultaneously collecting high chemical resolution mass spectra. Important considerations for obtaining high quality MALDI-MS images include tissue preservation, section preparation, MS data collection and data processing.
View Article and Find Full Text PDFBackground: Venous thromboembolism (VTE) is a common cause of serious morbidity and mortality. While chemoprophylaxis decreases VTE, there is the theoretical risk of increased hemorrhagic complications. The purpose of this study was to evaluate the impact of preoperative anticoagulation on VTE and bleeding complications in patients with blunt pelvic fractures requiring operative fixation.
View Article and Find Full Text PDFFatty acids (FAs) are central cellular metabolites that contribute to lipid synthesis, and can be stored or harvested for metabolic energy. Dysregulation in FA processing and storage causes toxic FA accumulation or altered membrane compositions and contributes to metabolic and neurological disorders. Saturated lipids are particularly detrimental to cells, but how lipid saturation levels are maintained remains poorly understood.
View Article and Find Full Text PDFInterest within the scientific community in organic solar cells has been on the rise over the last two decades as researchers respond to increasing demands for alternative renewable energy sources. Fulvene, fullerene, and endohedral metallofullerene derivatives have individually shown great promise as efficient charge transfer agents. Despite the heavy demand for research in this area, there have been no studies reported to date that explore the electronic behavior of molecules containing both fullerene and fulvene groups.
View Article and Find Full Text PDFCranial and craniospinal irradiation are the oldest central nervous system prophylaxis treatments considered for pediatric patients with acute lymphoblastic leukemia (ALL). However, survivors of childhood ALL that received cranial radiotherapy are at increased risk for deficits in neurocognitive skills. The continuous and dynamic response of normal tissue after irradiation has been identified as one of the causative factors for cognitive changes after cranial radiation therapy.
View Article and Find Full Text PDFThe data in this article are related to the research article "Utilizing the Regioselectivity of Perfluoropyridine towards the Preparation of Phenyoxyacetylene Precursors for Partially Fluorinated Polymers of Diverse Architecture." The X-ray structure analysis of 3,5-difluoro-2,6-bis(4-iodophenoxy)-4-phenoxypyridine has revealed an asymmetric unit containing two molecules, linked via both Type I and Type II C-I∙∙∙I-C halogen bonding interactions. The packing is further consolidated via Ar-H∙∙∙π interactions.
View Article and Find Full Text PDFComprehensive and unambiguous identification of small molecules in complex samples will revolutionize our understanding of the role of metabolites in biological systems. Existing and emerging technologies have enabled measurement of chemical properties of molecules in complex mixtures and, in concert, are sensitive enough to resolve even stereoisomers. Despite these experimental advances, small molecule identification is inhibited by (i) chemical reference libraries (e.
View Article and Find Full Text PDFPentafluoropyridine, a potentially useful precursor in organofluorine methodology, undergoes selective substitution of a fluorine with a phenoxide at the site to the nitrogen. Subsequent aryloxide substitutions can be accomplished at the -positions with aryloxide groups containing various functional groups to the phenoxide oxygen. During this phase of the reaction, "reverse reactions" involving substitutions of the original substituent with a free fluoride or with another aryloxide moiety are observed with a frequency that depends on the functional group to the oxygen on the aryloxide.
View Article and Find Full Text PDFActa Crystallogr E Crystallogr Commun
August 2019
Five new crystal structures of perfluoro-pyridine substituted in the 4-position with phen-oxy, 4-bromo-phen-oxy, naphthalen-2-yl-oxy, 6-bromo-naphthalen-2-yl-oxy, and 4,4'-biphen-oxy are reported, 2,3,5,6-tetra-fluoro-4-phen-oxy-pyridine, CHFNO (), 4-(4-bromo-phen-oxy)-2,3,5,6-tetra-fluoro-pyridine, CHBrFNO (), 2,3,5,6-tetra-fluoro-4-[(naphthalen-2-yl)-oxy]pyridine, CHFNO (), 4-[(6-bromo-naphthalen-2-yl)-oxy]-2,3,5,6-tetra-fluoropyridine, CHBrFNO (), and 2,2'-bis-[(perfluoro-pyridin-4-yl)-oxy]-1,1'-biphenyl, CHFNO (). The dihedral angles between the aromatic ring systems in - are 78.74 (8), 56.
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