45 research outputs found
Jack in the Box
Behold the bloodless puppet rising out a cheap quadrangular man-hole. Fluorescent mandarin hair forming a deceptive heart around alabaster skin, framing his daisy petal eyes, his pink colossal nose, and boomerang mouth.
~excerpt from poe
Doors
Staunch sentries of decision
gloating and imposing
tempting and untrustworthy. ~excerpt from poe
Molecular dissection of HERV-W dependent microglial- and astroglial cell polarization.
The endogenous retrovirus type W (HERV-W) is a human-specific entity, which was initially discovered in multiple sclerosis (MS) patient derived cells. We initially found that the HERV-W envelope (ENV) protein negatively affects oligodendrogenesis and controls microglial cell polarization towards a myelinated axon associated and damaging phenotype. Such first functional assessments were conducted ex vivo, given the human-specific origin of HERV-W. Recent experimental evidence gathered on a novel transgenic mouse model, mimicking activation and expression of the HERV-W ENV protein, revealed that all glial cell types are impacted and that cellular fates, differentiation, and functions were changed. In order to identify HERV-W-specific signatures in glial cells, the current study analyzed the transcriptome of ENV protein stimulated microglial- and astroglial cells and compared the transcriptomic signatures to lipopolysaccharide (LPS) stimulated cells, owing to the fact that both ligands can activate toll-like receptor-4 (TLR-4). Additionally, a comparison between published disease associated glial signatures and the transcriptome of HERV-W ENV stimulated glial cells was conducted. We, therefore, provide here for the first time a detailed molecular description of specific HERV-W ENV evoked effects on those glial cell populations that are involved in smoldering neuroinflammatory processes relevant for progression of neurodegenerative diseases
Safer Tripping: Serotonergic Psychedelics and Drug Checking. Submission and Detection Rates, Potential Harms, and Challenges for Drug Analysis
Purpose of Review With the continuous emergence of new psychoactive substances, drug checking (DC) services are challenged by an increasingly complex drug market. Considering the resumed scientific and public interest in serotonergic psychedelics (SPs) like LSD, psilocybin, and 2C-B, we present the results of a literature search investigating the presence and proportion of SPs in DC samples.
Recent Findings: In 15 identified reports, submission and detection rates of SPs were comparably low, but increasing. Samples contained considerable amounts of adulterations or analogues, mostly novel SPs with unknown toxicological profiles and in some cases potentially life-threatening effects. The detection of SPs, however, requires advanced analysis techniques currently not available to most DC services.
Summary: Given the substantial proportion of novel SPs in DC samples and the associated risks, DC can be a valuable harm reduction and monitoring tool for SPs if analysis techniques with high sensitivity are employed
A Novel Ex Vivo Model to Study Therapeutic Treatments for Myelin Repair following Ischemic Damage
Stroke is a major reason for persistent disability due to insufficient treatment strategies
beyond reperfusion, leading to oligodendrocyte death and axon demyelination, persistent inflammation and astrogliosis in peri-infarct areas. After injury, oligodendroglial precursor cells (OPCs)
have been shown to compensate for myelin loss and prevent axonal loss through the replacement
of lost oligodendrocytes, an inefficient process leaving axons chronically demyelinated. Phenotypic
screening approaches in demyelinating paradigms revealed substances that promote myelin repair.
We established an ex vivo adult organotypic coronal slice culture (OCSC) system to study repair
after stroke in a resource-efficient way. Post-photothrombotic OCSCs can be manipulated for 8 d
by exposure to pharmacologically active substances testing remyelination activity. OCSCs were
isolated from a NG2-CreERT2-td-Tomato knock-in transgenic mouse line to analyze oligodendroglial
fate/differentiation and kinetics. Parbendazole boosted differentiation of NG2+
cells and stabilized
oligodendroglial fate reflected by altered expression of associated markers PDGFR-α, CC1, BCAS1
and Sox10 and GFAP. In vitro scratch assay and chemical ischemia confirmed the observed effects
upon parbendazole treatment. Adult OCSCs represent a fast, reproducible, and quantifiable model
to study OPC differentiation competence after stroke. Pharmacological stimulation by means of
parbendazole promoted OPC differentiation
Transgenic expression of the HERV-W envelope protein leads to polarized glial cell populations and a neurodegenerative environment.
The human endogenous retrovirus type W (HERV-W) has been identified and repeatedly confirmed as human-specific pathogenic entity affecting many cell types in multiple sclerosis (MS). Our recent contributions revealed the encoded envelope (ENV) protein to disturb myelin repair by interfering with oligodendroglial precursor differentiation and by polarizing microglial cells toward an axon-damage phenotype. Indirect proof of ENV's antiregenerative and degenerative activities has been gathered recently in clinical trials using a neutralizing anti-ENV therapeutic antibody. Yet direct proof of its mode of action can only be presented here based on transgenic ENV expression in mice. Upon demyelination, we observed myelin repair deficits, neurotoxic microglia and astroglia, and increased axon degeneration. Experimental autoimmune encephalomyelitis activity progressed faster in mutant mice equally accompanied by activated glial cells. This study therefore provides direct evidence on HERV-W ENV's contribution to the overall negative impact of this activated viral entity in MS
Analytical study of waterlogged ivory from the Bajo de la campana site (Murcia, Spain)
[EN] This work reports an analytical study conducted prior to the conservation intervention of a collection of elephant tusks excavated from a wreck site of a 600-500 BC Phoenician trading vessel in Bajo de la campana (Murcia, Spain). The conservation state of ivory, determined by prolongated immersion in a marine environment, was established by a multi-technique methodology: light microscopy, field emission scanning electron microscopy X-ray microanalysis (FESEM-EDX), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), spectrophotometry and gas chromatography-mass spectrometry (GC-MS). The analyses demonstrated that the structure and composition of both tusk parts, namely the inner ivory and outer cementum, were altered due to characteristic diagenetic processes of a marine environment. Ca enrichment was observed in both tusk parts, which gave higher Ca/P molar ratio values than for ideal hydroxyapatite. Mg leaching was observed, together with uptake of exogenous elements (F, Cl, Si, Al, S, Na, Fe, Cu, Sr, Pb, Sn, Ag, V, Ni, Cd and Zn), which were prevalently identified in the external tusk part. Uptake of S and Fe was associated with the neoformation of pyrite framboids. The high carbonate content measured by FTIR, which agreed with the higher Ca/P ratios found in the archaeological tusk, was ascribed to the carbonate substitution of phosphate groups (type-B) in the bioapatite accompanied by some authigenic calcium carbonate that infilled ivory. An increased degree of crystallinity was observed when comparing the values of several crystallinity indices found in the archaeological bioapatite with those of a modern tusk, used as the reference material. Increased crystallinity prevalently took place in the cementurn. In accordance with increased crystallinity, the HPO42- content index indicated that the hydrated layer of bioapatite nanocrystals diminished in the archaeological tusk, and prevalently in the cementum. All these changes correlated with the significant organic matter loss reported for the archaeological tusk. Interestingly, remaining collagenous matter noticeably altered with enrichment in glycine and depletion in acid amino acids. Changes in the secondary structure of proteins were also recognised and associated with collagen gelatinisation. In addition to proteinaceous materials, small amounts of long-chain fatty acids, monoglycerides and cholesteryl oleate were identified by GC-MS. Cholesteryl oleate was associated with blood, which could have precipitated at the time of specimen death. The identification of large amounts of pyrite framboids and the high oleic acid/palmitic acid ratio in the archaeological tusk suggested minimal oxidative degradation processes, probably due to the slightly anoxic conditions of the underwater Bajo de la campana site environment. (C) 2016 Elsevier B.V. All rights reserved.The authors wish to thank CITES Espana and Direccion General de Bienes Culturales y Ensenanzas Artisticas, de la Consejeria de Educacion, Cultura y Universidades de la Comunidad Autonoma de la Region de Murcia, Museo Nacional de Arqueologia Subacuatica. Financial support is gratefully acknowledged from Spanish "I + D + I MINECO" projects CTQ2011-28079-CO3-01 and 02 and CTQ2014-53736-C3-1-P supported by ERDEF funds. The authors also wish to thank Mr. Manuel Planes and Dr. Jose Luis Moya, technical supervisors of the Electron Microscopy Service of the Universitat Politecnica de Valencia.Domenech Carbo, MT.; Buendía Ortuño, MDM.; Pasies Oviedo, T.; Osete Cortina, L. (2016). Analytical study of waterlogged ivory from the Bajo de la campana site (Murcia, Spain). Microchemical Journal. 126:381-405. https://doi.org/10.1016/j.microc.2015.12.022S38140512
Aberrant Oligodendrogenesis in Down Syndrome: Shift in Gliogenesis?
Down syndrome (DS), or trisomy 21, is the most prevalent chromosomal anomaly accounting for cognitive impairment and intellectual disability (ID). Neuropathological changes of DS brains are characterized by a reduction in the number of neurons and oligodendrocytes, accompanied by hypomyelination and astrogliosis. Recent studies mainly focused on neuronal development in DS, but underestimated the role of glial cells as pathogenic players. Aberrant or impaired differentiation within the oligodendroglial lineage and altered white matter functionality are thought to contribute to central nervous system (CNS) malformations. Given that white matter, comprised of oligodendrocytes and their myelin sheaths, is vital for higher brain function, gathering knowledge about pathways and modulators challenging oligodendrogenesis and cell lineages within DS is essential. This review article discusses to what degree DS-related effects on oligodendroglial cells have been described and presents collected evidence regarding induced cell-fate switches, thereby resulting in an enhanced generation of astrocytes. Moreover, alterations in white matter formation observed in mouse and human post-mortem brains are described. Finally, the rationale for a better understanding of pathways and modulators responsible for the glial cell imbalance as a possible source for future therapeutic interventions is given based on current experience on pro-oligodendroglial treatment approaches developed for demyelinating diseases, such as multiple sclerosis