Search results for " Root"
showing 10 items of 627 documents
Sex-specific interaction between arbuscular mycorrhizal and dark septate fungi in the dioecious plant Antennaria dioica (Asteraceae).
2012
Male and female plants of dioecious species often differ in their resource demands and this has been linked to secondary sexual dimorphism, including sex-specific interactions with other organisms such as herbivores and pollinators. However, little is known about the interaction between dioecious plants and fungal root endophytes. Plants may be simultaneously colonised by arbuscular mycorrhizal (AM) and dark septate (DS) fungi. While it is well established that AM mutualism involves reciprocal transfer of photosynthates and mineral nutrients between roots of host plants and these fungi, the role of DS fungi remains controversial. Here, we report the temporal and spatial variation in AM and …
Distribution, classification, and development ofDrosophila glial cells in the late embryonic and early larval ventral nerve cord.
1994
To facilitate the investigation of glial development inDrosophila, we present a detailed description of theDrosophila glial cells in the ventral nerve cord. A GAL4 enhancer-trap screen for glial-specific expression was performed. Using UAS-lacZ and UAS-kinesin-lacZ as reporter constructs, we describe the distribution and morphology of the identified glial cells in the fully differentiated ventral nerve cord of first-instar larvae just after hatching. The three-dimensional structure of the glial network was reconstructed using a computer. Using the strains with consistent GAL4 expression during late embryogenesis, we traced back the development of the identified cells to provide a glial map …
Injections of Particulate Steroids for Nerve Root Blockade: Ultrastructural Examination of Complicating Factors
2014
Selective nerve root block by a transforaminal approach with radiological control allows injection of an appropriate corticosteroid next to the nerve root, although it has been associated with major neurological complications in a few cases. There have been several reports in which corticosteroid injections performed at the level of the cervical or lumbar spine have led to severe spinal cord ischemic infarction. These have occurred independently of whether the procedure was performed under radiological control, in which the tip of the needle is identified to prevent vascular spreading of the solution injected.
Vulnerability of different nerves to intrafascicular injection by different needle types and at different approach angles: a mathematical model
2019
Background and objectivesWe assume that intrafascicular spread of a solution can only occur if a large enough portion of the distal needle orifice is placed inside the fascicle. Our aim is to present and evaluate a mathematical model that can calculate the theoretical vulnerability of fascicles, analyzing the degree of occupancy of the needle orifice in fascicular tissue by performing simulations of multiple positions that a needle orifice can take inside a cross-sectional nerve area.MethodsWe superimposed microscopic images of two routinely used nerve block needles (22-gauge, 15° needle and 22-gauge, 30° needle) over the microscopic images of cross-sections of four nerve types photographed…
Interleukin-6 (IL-6) and its soluble receptor support survival of sensory neurons
1999
The cytokine interleukin-6 (IL-6) has multiple functions in the immune and hematopoietic systems. IL-6 is related to ciliary neurotrophic factor (CNTF), a trophic factor for motoneurons, sensory dorsal root ganglion (DRG) neurons, and other neuronal subpopulations. Both act via related receptor complexes, consisting of one ligand-specific α-receptor subunit (IL-6R and CNTFR, respectively) and two signal-transducing receptor components. Even though IL-6 is expressed by neurons and glia, the functions of IL-6 in the nervous system are poorly understood. Here, we report that exogenous human IL-6 promotes the survival of dissociated newborn rat DRG neurons in vitro if supplemented with soluble …
Engineered axon tracts within tubular biohybrid scaffolds
2021
[EN] Injuries to the nervous system that involve the disruption of axonal pathways are devastating to the individual and require specific tissue engineering strategies. Here we analyse a cells-biomaterials strategy to overcome the obstacles limiting axon regeneration in vivo, based on the combination of a hyaluronic acid (HA) single-channel tubular conduit filled with poly-L-lactide acid (PLA) fibres in its lumen, with pre-cultured Schwann cells (SCs) as cells supportive of axon extension. The HA conduit and PLA fibres sustain the proliferation of SC, which enhance axon growth acting as a feeder layer and growth factor pumps. The parallel unidirectional ensemble formed by PLA fibres and SC …
Co-expression of heat sensitive vanilloid receptor subtypes in rat dorsal root ganglion neurons
2003
Expression of the heat sensitive cation channels TRPV1 and TRPV2 was investigated by immunofluorescence in rat dorsal root ganglion (DRG) neurons. TRPV1-positive neurons were more frequent and had smaller diameters than TRPV2-positive neurons (35.7% vs 7.3%; 22.3 microm vs 27.6 microm), but size distributions overlapped and significant co-expression was seen in 20.7% of TRPV2-positive neurons (1.7% of all). Expression patterns did not differ between tissue sections typically used in immunocytochemistry and dissociated DRG neurons typically used in electrophysiology. Rectangular temperature pulses revealed two patterns of heat-evoked inward currents in small DRG neurons: low-threshold rapidl…
Viaggi nell’immaginario: il turismo virtuale nel sito UNESCO di Tarragona
2023
Le nuove tecnologie hanno trasformato in modo radicale non solo la geografia come disciplina, ma anche le geografie del mondo. Il digitale ha assunto, infatti, un ruolo di mediazione sempre più pervasivo nella produzione dello spazio, come delle conoscenze e degli immaginari geografici. Le possibilità offerte dal virtuale, in particolare, offrono oggi un contributo decisivo nella comunicazione dei significati attribuiti ai luoghi e rispondono in modo sempre più efficace ai bisogni emergenti del settore turistico. Le esperienze di visita mediate dal digitale mirano a coinvolgere i sensi e risultano efficaci quando promuovono immersioni rigorosamente realistiche. Nel quadro di queste riflessi…
Search for the Standard Model Higgs boson at LEP in the year 2000
2001
Searches for the Standard Model Higgs boson have been performed in the data collected by the DELPHI experiment at LEP in the year 2000 at centre-of-mass energies between 200 and 209 GeV corresponding to a total integrated luminosity of 224 pb^{-1}. No evidence for a Higgs signal is observed in the kinematically accessible mass range, and a 95% CL lower mass limit of 114.3 GeV/c^2 is set, to be compared with an expected median limit of 113.5 GeV/c^2 for these data.
Search for Neutral Higgs Bosons in Events with Multiple Bottom Quarks at the Tevatron
2012
The combination of searches performed by the CDF and D0 collaborations at the Fermilab Tevatron Collider for neutral Higgs bosons produced in association with b quarks is reported. The data, corresponding to 2.6fb -1 of integrated luminosity at CDF and 5.2fb -1 at D0, have been collected in final states containing three or more b jets. Upper limits are set on the cross section multiplied by the branching ratio varying between 44 pb and 0.7 pb in the Higgs boson mass range 90 to 300 GeV, assuming production of a narrow scalar boson. Significant enhancements to the production of Higgs bosons can be found in theories beyond the standard model, for example, in supersymmetry. The results are int…