233 research outputs found
Intramuscular delivery of gene therapy for targeting the nervous system
Virus-mediated gene therapy has the potential to deliver exogenous genetic material
into specific cell types to promote survival and counteract disease. This is particularly
enticing for neuronal conditions, as the nervous system is renowned for its intransigence
to therapeutic targeting. Administration of gene therapy viruses into skeletal muscle,
where distal terminals of motor and sensory neurons reside, has been shown to result
in extensive transduction of cells within the spinal cord, brainstem, and sensory ganglia.
This route is minimally invasive and therefore clinically relevant for gene therapy targeting
to peripheral nerve soma. For successful transgene expression, viruses administered
into muscle must undergo a series of processes, including host cell interaction and
internalization, intracellular sorting, long-range retrograde axonal transport, endosomal
liberation, and nuclear import. In this review article, we outline key characteristics of major
gene therapy viruses—adenovirus, adeno-associated virus (AAV), and lentivirus—and
summarize the mechanisms regulating important steps in the virus journey from
binding at peripheral nerve terminals to nuclear delivery. Additionally, we describe how
neuropathology can negatively influence these pathways, and conclude by discussing
opportunities to optimize the intramuscular administration route to maximize gene
delivery and thus therapeutic potential
Travelling Together: A Unifying Pathomechanism for ALS
Axonal transport is critical for neuronal homeostasis and relies on motor complexes bound to cargoes via specific adaptors. However, the mechanisms responsible for the spatiotemporal regulation of axonal transport are not completely understood. A recent study by Liao et al. contributes to filling this gap by reporting that RNA granules ‘hitchhike’ on LAMP1-positive organelles using annexin A11 as a tether
Expanding the Toolkit for In Vivo Imaging of Axonal Transport
Axonal transport maintains neuronal homeostasis by enabling the bidirectional trafficking of diverse organelles and cargoes. Disruptions in axonal transport have devastating consequences for individual neurons and their networks, and contribute to a plethora of neurological disorders. As many of these conditions involve both cell autonomous and non-autonomous mechanisms, and often display a spectrum of pathology across neuronal subtypes, methods to accurately identify and analyze neuronal subsets are imperative.
This paper details protocols to assess in vivo axonal transport of signaling endosomes and mitochondria in sciatic nerves of anesthetized mice. Stepwise instructions are provided to 1) distinguish motor from sensory neurons in vivo, in situ, and ex vivo by using mice that selectively express fluorescent proteins within cholinergic motor neurons; and 2) separately or concurrently assess in vivo axonal transport of signaling endosomes and mitochondria. These complementary intravital approaches facilitate the simultaneous imaging of different cargoes in distinct peripheral nerve axons to quantitatively monitor axonal transport in health and disease
Assessing Rat Forelimb and Hindlimb Motor Unit Connectivity as Objective and Robust Biomarkers of Spinal Motor Neuron Function
Sensitive and objective biomarkers of neuronal injury, degeneration, and regeneration can help facilitate translation of experimental findings into clinical testing. Whereas measures of upper motor neuron connectivity have been readily established, functional assessments of lower motor neuron (LMN) innervation of forelimb muscles are lacking. Compound muscle action potential (CMAP) and motor unit (MU) number estimation (MUNE) are well-established methods that allow longitudinal MU integrity monitoring in patients. In analogy we refined CMAP and MUNE methods for assessing spinal MU input in the rat forelimb and hindlimb. Repeated CMAP and MUNE recordings are robust (coefficients of variability: 4.5–11.3%), and MUNE measurements from forelimb wrist flexor muscles (415 ± 8 [SEM]) align with back-traced anatomical LMN counts (336 ± 16 [SEM]). For disease validation, cross-sectional blinded electrophysiological and muscle contractility measurements were obtained in a cohort of G93A SOD1 mutant overexpressing rats and compared with controls. Longitudinal assessment of mutant animals demonstrated progressive motor unit decline in the hindlimb to a greater extent than the forelimb. Hindlimb CMAP and MUNE demonstrated strong correlations with plantarflexion muscle contractility. Cross-species assessment of upper/fore- limb and lower/hind- limb motor units using objective electrophysiological CMAP and MUNE values as biomarkers will guide and improve bi-directional translation
Essential Oils and Their Principal Constituents as Antimicrobial Agents for Synthetic Packaging Films
Spices and herbal plant species have been recognized to possess a broad spectrum of active constituents that exhibit antimicrobial (AM) activity. These active compounds are produced as secondary metabolites associated with the volatile essential oil (EO) fraction of these plants. A wide range of AM agents derived from EOs have the potential to be used in AM packaging systems which is one of the promising forms of active packaging systems aimed at protecting food products from microbial contamination. Many studies have evaluated the AM activity of synthetic AM and/or natural AM agents incorporated into packaging materials and have demonstrated effective AM activity by controlling the growth of microorganisms. This review examines the more common synthetic and natural AM agents incorporated into or coated onto synthetic packaging films for AM packaging applications. The focus is on the widely studied herb varieties including basil, oregano, and thyme and their EOs
Synthesis and complexing properties of cyclic benzylopeptoids-a new family of extended macrocyclic peptoids
An efficient protocol for the solid-phase synthesis of six members of a new class of extended macrocyclic
peptoids (based on ortho-, meta- and para-N-(methoxyethyl)aminomethyl phenylacetyl units) is
described. Theoretical (DFT) and experimental (NMR) studies on the free and Na+-complexed cyclic
trimers (3\u20135) and tetramers (6\u20138) demonstrate that annulation of the rigidified peptoids can generate
new hosts with the ability to sequestrate one or two sodium cations with the affinities and stoichiometries
defined by the macrocycle morphology. Ion transport studies have been also performed in order to better
appreciate the factors promoting transmembrane cation translocation
A phase 1 clinical trial of vorinostat in combination with decitabine in patients with acute myeloid leukaemia or myelodysplastic syndrome
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108599/1/bjh13016.pd
Pancreatic cancer intrinsic PI3Kα activity accelerates metastasis and rewires macrophage component.
Pancreatic ductal adenocarcinoma (PDAC) patients frequently suffer from undetected micro-metastatic disease. This clinical situation would greatly benefit from additional investigation. Therefore, we set out to identify key signalling events that drive metastatic evolution from the pancreas. We searched for a gene signature that discriminate localised PDAC from confirmed metastatic PDAC and devised a preclinical protocol using circulating cell-free DNA (cfDNA) as an early biomarker of micro-metastatic disease to validate the identification of key signalling events. An unbiased approach identified, amongst actionable markers of disease progression, the PI3K pathway and a distinctive PI3Kα activation signature as predictive of PDAC aggressiveness and prognosis. Pharmacological or tumour-restricted genetic PI3Kα-selective inhibition prevented macro-metastatic evolution by hindering tumoural cell migratory behaviour independently of genetic alterations. We found that PI3Kα inhibition altered the quantity and the species composition of the produced lipid second messenger PIP3 , with a selective decrease of C36:2 PI-3,4,5-P3 . Tumoural PI3Kα inactivation prevented the accumulation of pro-tumoural CD206-positive macrophages in the tumour-adjacent tissue. Tumour cell-intrinsic PI3Kα promotes pro-metastatic features that could be pharmacologically targeted to delay macro-metastatic evolution
Recarga artificial en Bajos Submeridionales
Se presenta la experiencia en desarrollo en un sector de Bajos Submeridionales próximo a Tostado, para monitorear los efectos de la recarga artificial de acuíferos. El objetivo del estudio es mejorar la disponibilidad de agua en calidad y cantidad para uso ganadero y evaluar una obra de recarga a partir de un pozo doble propósito recarga – bombeo para mejorar su eficiencia, y difundir estas prácticas.El área piloto se ubica en un paleocauce arenoso del río Salado. En el mismo se han realizado numerosos estudios geoeléctricos, de infiltración, sedimentológicos, químicos recuperación de niveles, de suelos y de recarga. Además se dispone de una estación meteorológica automática, caudalímetro y freatímetros. Se realizó un análisis de eventos de recarga y su efecto sobre el sistema natural y en la obra. Se concluye que ha resultado exitosa y puede ser transferida a otros ambientes de paleocauces del chaco-santafesino.This work describes an artificial recharge experience of groundwater as source for animal beverage, de veloped on a livestock demonstrative unit, placed in Bajos Submeridionales, Santa Fe province, Argentina. The aim of this study is to improve quality and quantity of water for livestock use, analyze a recharge-pumping well efficiency, and finally to spread this practice in the region. The study area is located in a antique sandy channel of the Salado river, where have been conducted geoelectric studies, sedimentologic, soil and water analysis, pumping and recharge, and infiltration tests. Additionally, it counts with metheorological on-line data from an automatic station, flowmeter, and water-level measurements from digital and analogical devises. An analysis of a recharge event has been conducted in order to assess environmental changes and response of facilities. This successful experience suggests that these kinds of facilities could be applied in similar environments of chaco-santafesino region.Universidad Nacional de La Plat
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