c-Maf-positive spinal cord neurons are critical elements of a dorsal horn circuit for mechanical hypersensitivity in neuropathy

Solvent-thermal approach of MIL-100(Fe)/Cygnea/Fe3O4/TiO2 nanocomposite for the treatment of lead from oil refinery wastewater (ORW) under UVA light

The main purpose of this research endeavor is to reduce lead concentrations in the wastewater of an oil refinery through the utilization of a material composed of oyster shell waste (MIL-100(Fe)/Cygnea/Fe3O4/TiO2. Initially, iron oxide nanoparticles (Fe3O4) were synthesized via solvent-thermal synthesis. It was subsequently coated layer by layer with the organic-metallic framework MIL-100 (Fe) using the core-shell method. Additionally, the solvent-thermal method was utilized to integrate TiO2 nanoparticles into the magnetic organic-metallic framework's structure. Varieties of analytical analysis were utilized to investigate the physical and chemical properties of the synthetic final photocatalyst. Nitrogen adsorption and desorption technique (BET), scanning electron microscopy (SEM), scanning electron diffraction pattern (XRD), and transmission electron microscopy (TEM). Following the characterization of the final photocatalyst, the physical and chemical properties of the nanoparticles synthesized in each step, several primary factors that significantly affect the removal efficiency in the advanced oxidation system (AOPs) were examined. These variables consist of pH, photocatalyst dosage, lead concentration, and reaction temperature. The synthetic photocatalyst showed optimal performance in the removal of lead from petroleum wastewater under the following conditions: 35 °C temperature, pH of 3, 0.04 g/l photocatalyst dosage, and 100 mg/l wastewater concentration. Additionally, the photocatalyst maintained a significant level of reusability after undergoing five cycles. The findings of the study revealed that the photocatalyst dosage and pH were the most influential factors in the effectiveness of lead removal. According to optimal conditions, lead removal reached a maximum of 96%. The results of this investigation showed that the synthetic photocatalyst, when exposed to UVA light, exhibited an extraordinary capacity for lead removal.

SPINAL V1 INHIBITORY INTERNEURON CLADES DIFFER IN BIRTHDATE, PROJECTIONS TO MOTONEURONS AND HETEROGENEITY

Spinal cord interneurons play a crucial role in shaping motor output, but their precise identity and circuit connectivity remain unclear. Focusing on the cardinal class of inhibitory V1 interneurons, we define the diversity of four major V1 subsets according to timing of neurogenesis, genetic lineage-tracing, synaptic output to motoneurons, and synaptic inputs from muscle afferents. Birthdating delineates two early-born (Renshaw and Pou6f2) and two late-born V1 clades (Foxp2 and Sp8) suggesting sequential neurogenesis gives rise to different V1 clades. Neurogenesis did not correlate with motoneuron targeting. Early-born Renshaw cells and late-born Foxp2-V1 interneurons both tightly coupled to motoneurons, while early-born Pou6f2-V1 and late-born Sp8-V1 interneurons did not. V1-clades also greatly differ in cell numbers and diversity. Lineage labeling of the Foxp2-V1 clade shows it contains over half of all V1 interneurons and provides the largest inhibitory input to motoneuron cell bodies. Foxp2-V1 subgroups differ in neurogenesis and proprioceptive input. Notably, one subgroup defined by Otp expression and located adjacent to the lateral motor column exhibits substantial input from proprioceptors, consistent with some Foxp2-V1 cells at this location forming part of reciprocal inhibitory pathways. This was confirmed with viral tracing methods for ankle flexors and extensors. The results validate the previous V1 clade classification as representing unique interneuron subtypes that differ in circuit placement with Foxp2-V1s forming the more complex subgroup. We discuss how V1 organizational diversity enables understanding of their roles in motor control, with implications for the ontogenetic and phylogenetic origins of their diversity.

SIGNIFICANCE STATEMENT

Spinal interneuron diversity and circuit organization represents a key challenge to understand the neural control of movement in normal adults and also during motor development and in disease. Inhibitory interneurons are a core element of these spinal circuits, acting on motoneurons either directly or via premotor networks. V1 interneurons comprise the largest group of inhibitory interneurons in the ventral horn and their organization remains unclear. Here we present a comprehensive examination of V1 subtypes according to neurogenesis, placement in spinal motor circuits and motoneuron synaptic targeting. V1 diversity increases during evolution from axial-swimming fishes to limb-based mammalian terrestrial locomotion and this is reflected in the size and heterogeneity of the Foxp2-V1 clade which is closely associated to limb motor pools. We show Foxp2-V1 interneurons establish the densest and more direct inhibitory synaptic input to motoneurons, especially on cell bodies. This is of further importance because deficits on motoneuron cell body inhibitory V1 synapses and on Foxp2-V1 interneurons themselves have recently been shown to be affected at early stages of pathology in motor neurodegenerative diseases like amyotrophic lateral sclerosis.

Neuropathic pain; what we know and what we should do about it

Neuropathic pain can result from injury to, or disease of the nervous system. It is notoriously difficult to treat. Peripheral nerve injury promotes Schwann cell activation and invasion of immunocompetent cells into the site of injury, spinal cord and higher sensory structures such as thalamus and cingulate and sensory cortices. Various cytokines, chemokines, growth factors, monoamines and neuropeptides effect two-way signalling between neurons, glia and immune cells. This promotes sustained hyperexcitability and spontaneous activity in primary afferents that is crucial for onset and persistence of pain as well as misprocessing of sensory information in the spinal cord and supraspinal structures. Much of the current understanding of pain aetiology and identification of drug targets derives from studies of the consequences of peripheral nerve injury in rodent models. Although a vast amount of information has been forthcoming, the translation of this information into the clinical arena has been minimal. Few, if any, major therapeutic approaches have appeared since the mid 1990's. This may reflect failure to recognise differences in pain processing in males vs. females, differences in cellular responses to different types of injury and differences in pain processing in humans vs. animals. Basic science and clinical approaches which seek to bridge this knowledge gap include better assessment of pain in animal models, use of pain models which better emulate human disease, and stratification of human pain phenotypes according to quantitative assessment of signs and symptoms of disease. This can lead to more personalized and effective treatments for individual patients. Significance statement: There is an urgent need to find new treatments for neuropathic pain. Although classical animal models have revealed essential features of pain aetiology such as peripheral and central sensitization and some of the molecular and cellular mechanisms involved, they do not adequately model the multiplicity of disease states or injuries that may bring forth neuropathic pain in the clinic. This review seeks to integrate information from the multiplicity of disciplines that seek to understand neuropathic pain; including immunology, cell biology, electrophysiology and biophysics, anatomy, cell biology, neurology, molecular biology, pharmacology and behavioral science. Beyond this, it underlines ongoing refinements in basic science and clinical practice that will engender improved approaches to pain management.