Project description:Campylobacter jejuni (C. jejuni) protein microarrays were used to identify immunogenic C. jejuni proteins that may be useful in the development of biomarkers, diagnostic assays, or subunit vaccines for humans or livestock. A native protein microarray with over 1400 individually purified GST-tagged C. jejuni proteins (86 % of the proteome), was constructed and screened for antibody titers present in test sera. The protein arrays were screened with antisera from rabbits inoculated with whole C. jejuni or various serotypes of E. coli or Salmonella, with antisera from mice infected with C. jejuni, and sera from healthy humans. Dual detection of GST signals was incorporated as a way of normalizing the variation of protein concentrations contributing to the antibody staining intensities.
Project description:To investigate the effect of mechanical ventilation and mechanical ventilationon with PEEP application on diaphragmatic dysfunction, we established a model of mechanical ventilation on New Zealand rabbit, in which rabbits in the experimental group were ventilated with/without PEEP application for 48 hours continuously
Project description:Spinal microglia play a pivotal role in the development of neuropathic pain. Peripheral nerve injury induces changes in the transcriptional profile of microglia, including increased expression of components of translational machinery. Whether microglial protein synthesis is stimulated following nerve injury and has a functional role in mediating pain hypersensitivity is unknown. Here, we show that nascent protein synthesis is upregulated in spinal microglia following peripheral nerve injury. Stimulating mRNA translation in microglia, via selective ablation of the translational repressor, eukaryotic initiation factor 4E-binding protein 1 (4E-BP1), promoted the transition of microglia to a reactive state and induced mechanical hypersensitivity. Conversely, inhibiting microglial translation by expressing mutant 4E-BP1 in microglia attenuated their peripheral nerve injury-induced activation and alleviated neuropathic pain. Thus, the stimulation of 4E-BP1-dependent translation promotes microglia reactivity and mechanical hypersensitivity, whereas its inhibition alleviates neuropathic pain.
Project description:Peripheral nerve injury alters the expression of hundreds of proteins in dorsal root ganglia (DRG). Targeting some of these proteins has led to successful treatments for acute pain, but not for sustained postoperative neuropathic pain. The latter may require targeting multiple proteins. Since a single microRNA (miR) can affect the expression of multiple proteins, here, we describe an approach to identify chronic neuropathic pain-relevant miRs. We used two variants of the spared nerve injury (SNI): Sural-SNI and Tibial-SNI and found distinct pain phenotypes between the two. Both models induced strong mechanical allodynia, but only Sural-SNI rats maintained strong mechanical and cold allodynia, as previously reported. In contrast, we found that Tibial-SNI rats recovered from mechanical allodynia and never developed cold allodynia. Since both models involve nerve injury, we increased the probability of identifying differentially regulated miRs that correlated with the quality and magnitude of neuropathic pain and decreased the probability of detecting miRs that are solely involved in neuronal regeneration. We found seven such miRs in L3-L5 DRG. The expression of these miRs increased in Tibial-SNI. These miRs displayed a lower level of expression in Sural-SNI, with four having levels lower than those in sham animals. Bioinformatics analysis of how these miRs could affect the expression of some ion channels supports the view that, following a peripheral nerve injury, the increase of the 7 miRs may contribute to the recovery from neuropathic pain while the decrease of four of them may contribute to the development of chronic neuropathic pain. The approach used resulted in the identification of a small number of potentially neuropathic pain relevant miRs. Additional studies are required to investigate whether manipulating the expression of the identified miRs in primary sensory neurons can prevent or ameliorate chronic neuropathic pain following peripheral nerve injuries. To identify the miRs that were differentially dysregulated between Tibial-SNI and Sural-SNI, we first performed 12 microarrays in a limited number of samples (in four individual DRGs per group: Sham, Tibial-SNI and Sural-SNI; two L3-DRG and two L4-DRG). Then, miRs identified as having differential expression were corroborated with real time qRT-PCR in RNA isolated from individual DRGs (L3, L4 and L5) derived from 4 rats per group (not presented here, but in the manuscript).
Project description:Peripheral nerve injury alters the expression of hundreds of proteins in dorsal root ganglia (DRG). Targeting some of these proteins has led to successful treatments for acute pain, but not for sustained postoperative neuropathic pain. The latter may require targeting multiple proteins. Since a single microRNA (miR) can affect the expression of multiple proteins, here, we describe an approach to identify chronic neuropathic pain-relevant miRs. We used two variants of the spared nerve injury (SNI): Sural-SNI and Tibial-SNI and found distinct pain phenotypes between the two. Both models induced strong mechanical allodynia, but only Sural-SNI rats maintained strong mechanical and cold allodynia, as previously reported. In contrast, we found that Tibial-SNI rats recovered from mechanical allodynia and never developed cold allodynia. Since both models involve nerve injury, we increased the probability of identifying differentially regulated miRs that correlated with the quality and magnitude of neuropathic pain and decreased the probability of detecting miRs that are solely involved in neuronal regeneration. We found seven such miRs in L3-L5 DRG. The expression of these miRs increased in Tibial-SNI. These miRs displayed a lower level of expression in Sural-SNI, with four having levels lower than those in sham animals. Bioinformatics analysis of how these miRs could affect the expression of some ion channels supports the view that, following a peripheral nerve injury, the increase of the 7 miRs may contribute to the recovery from neuropathic pain while the decrease of four of them may contribute to the development of chronic neuropathic pain. The approach used resulted in the identification of a small number of potentially neuropathic pain relevant miRs. Additional studies are required to investigate whether manipulating the expression of the identified miRs in primary sensory neurons can prevent or ameliorate chronic neuropathic pain following peripheral nerve injuries.
Project description:To identify the changes in gene expression profile caused by mechanical stress in the ligamentum flavum, we performed resection of the L3-4 supraspinal muscle and L2-3, L4-5 posterolateral fusion with instrumentation to concentrate the mechanical stress with segmental instability at the L3-4 level. The control group underwent only surgical exposure as a sham operation. Both groups of rabbits were sacrificed at 1 year after surgery and total RNA were extracted from ligamentum flavum.
Project description:To identify the changes in gene expression profile caused by mechanical stress in the ligamentum flavum, we performed resection of the L3-4 supraspinal muscle and L2-3, L4-5 posterolateral fusion with instrumentation to concentrate the mechanical stress with segmental instability at the L3-4 level. The control group underwent only surgical exposure as a sham operation. Both groups of rabbits were sacrificed at 16 weeks after surgery and total RNA were extracted from ligamentum flavum.
Project description:The goal of this study was to evaluate the impact of mechanical ventilation on immune and mitochondrial dysfunctions, in the setting of pneumococcal pneumonia in rabbits. Then, in a randomized trial, we assessed the effect of human umbilical cord-derived mesenchymal stem cells (MSCs), either alone, or in association with an atibiotic treatment (Ceftaroline) in the setting of pneumococcal pneumonia submitted to adverse mechanical ventilation. Pulmonary gene expression was analysed in an attempt to elucidate the effects of MSCs.
Project description:To elucidate the molecular mechanism behind the anti-NAFLD effect of HDCA, we screened for potential HDCA binding proteins using biotin-labeled HDCA and HuProt human proteome microarray.
Project description:Here we identified two populations of myelinated sensory neurons that display markedly different phenotypes in terms of their action potential characteristics and responses to mechanical stimuli based on their expression of Calcitonin Gene-Related Peptide (CGRP). Myelinated neurons that did not express CGRP responded to mechanical stimuli with significantly larger currents during whole-cell voltage clamp recordings than their CGRP-positive counterparts, regardless of whether these neurons projected to the dorsal hindpaw skin or the gastrocnemius muscle. Importantly, this discrepancy could not be explained by a differential expression of mechanosensitive or mechanically-gated proteins like Stoml3 or Piezo2. Following inflammation of the skin or muscle, myelinated neurons demonstrated a sensitization to mechanical stimuli characterized by increased current amplitudes. Interestingly, myelinated neurons expressing CGRP are sensitized to mechanical stimuli following cutaneous inflammation of the paw, while myelinated neurons that do not express CGRP are sensitized to mechanical stimuli following inflammation of the gastrocnemius muscle. Microarray data was obtained from these populations by first using Fluorescence-Activated Cell Sorting (FACS) to separate the populations of interest. 15 different samples were analyzed, 3 biological replicates for each group (5 groups: saline paw-injected, CFA paw-injected, saline muscle-injected, acid muscle-injected, and CFA muscle-injected). The saline injected groups (paw and muscle) are considered controls.