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1.
Sensors (Basel) ; 24(6)2024 Mar 11.
Article in English | MEDLINE | ID: mdl-38544055

ABSTRACT

Aiming at the traditional single sensor vibration signal cannot fully express the bearing running state, and in the high noise background, the traditional algorithm is insufficient for fault feature extraction. This paper proposes a fault diagnosis algorithm based on multi-sensor and hybrid multimodal feature fusion to achieve high-precision fault diagnosis by leveraging the operating state information of bearings in a high-noise environment to the fullest extent possible. First, the horizontal and vertical vibration signals from two sensors are fused using principal component analysis, aiming to provide a more comprehensive description of the bearing's operating condition, followed by data set segmentation. Following fusion, time-frequency feature maps are generated using a continuous wavelet transform for global time-frequency feature extraction. A first diagnostic model is then developed utilizing a residual neural network. Meanwhile, the feature data is normalized, and 28 time-frequency feature indexes are extracted. Subsequently, a second diagnostic model is constructed using a support vector machine. Lastly, the two diagnosis models are integrated to derive the final model through an ensemble learning algorithm fused at the decision level and complemented by a genetic algorithm solution to improve the diagnosis accuracy. Experimental results demonstrate the effectiveness of the proposed algorithm in achieving superior diagnostic performance with a 97.54% accuracy rate.

2.
Cell Rep ; 42(2): 112133, 2023 02 28.
Article in English | MEDLINE | ID: mdl-36800288

ABSTRACT

Expansion of the hexanucleotide repeat GGGGCC in the C9orf72 gene is the most common genetic factor in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Poly-Gly-Ala (poly-GA), one form of dipeptide repeat proteins (DPRs) produced from GGGGCC repeats, tends to form neurotoxic protein aggregates. The C9orf72 GGGGCC repeats and microglial receptor TREM2 are both associated with risk for ALS/FTD. The role and regulation of TREM2 in C9orf72-ALS/FTD remain unclear. Here, we found that poly-GA proteins activate the microglial NLRP3 inflammasome to produce interleukin-1ß (IL-1ß), which promotes ADAM10-mediated TREM2 cleavage and inhibits phagocytosis of poly-GA. The inhibitor of the NLRP3 inflammasome, MCC950, reduces the TREM2 cleavage and poly-GA aggregates, resulting in the alleviation of motor deficits in poly-GA mice. Our study identifies a crosstalk between NLRP3 and TREM2 signaling, suggesting that targeting the NLRP3 inflammasome to sustain TREM2 is an approach to treat C9orf72-ALS/FTD.


Subject(s)
Amyotrophic Lateral Sclerosis , Frontotemporal Dementia , Animals , Mice , Amyotrophic Lateral Sclerosis/genetics , Amyotrophic Lateral Sclerosis/metabolism , C9orf72 Protein/genetics , C9orf72 Protein/metabolism , Dipeptides/metabolism , DNA Repeat Expansion , Frontotemporal Dementia/genetics , Inflammasomes , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , Proteins/genetics
3.
Nat Commun ; 14(1): 4, 2023 01 03.
Article in English | MEDLINE | ID: mdl-36596769

ABSTRACT

Transient receptor potential vanilloid 1 (TRPV1) ion channel is a classic analgesic target, but antagonists of TRPV1 failed in clinical trials due to their side effects like hyperthermia. Here we rationally engineer a peptide s-RhTx as a positive allosteric modulator (PAM) of TRPV1. Patch-clamp recordings demonstrate s-RhTx selectively potentiated TRPV1 activation. s-RhTx also slows down capsaicin-induced desensitization of TRPV1 in the presence of calcium to cause more calcium influx in TRPV1-expressing cells. In addition, our thermodynamic mutant cycle analysis shows that E652 in TRPV1 outer pore specifically interacts with R12 and K22 in s-RhTx. Furthermore, we demonstrate in vivo that s-RhTx exhibits long-lasting analgesic effects in noxious heat hyperalgesia and CFA-induced chronic inflammatory pain by promoting the reversible degeneration of intra-epidermal nerve fiber (IENF) expressing TRPV1 channels in mice, while their body temperature remains unaffected. Our results suggest s-RhTx is an analgesic agent as a PAM of TRPV1.


Subject(s)
Analgesia , Transient Receptor Potential Channels , Mice , Animals , Calcium , TRPV Cation Channels/genetics , Pain/drug therapy , Analgesics/pharmacology , Analgesics/therapeutic use , Capsaicin/pharmacology , Peptides/pharmacology , Peptides/therapeutic use
4.
Neurosci Bull ; 39(5): 745-758, 2023 May.
Article in English | MEDLINE | ID: mdl-36587114

ABSTRACT

Diabetic neuropathic pain (DNP) is the most common disabling complication of diabetes. Emerging evidence has linked the pathogenesis of DNP to the aberrant sprouting of sensory axons into the epidermal area; however, the underlying molecular events remain poorly understood. Here we found that an axon guidance molecule, Netrin-3 (Ntn-3), was expressed in the sensory neurons of mouse dorsal root ganglia (DRGs), and downregulation of Ntn-3 expression was highly correlated with the severity of DNP in a diabetic mouse model. Genetic ablation of Ntn-3 increased the intra-epidermal sprouting of sensory axons and worsened the DNP in diabetic mice. In contrast, the elevation of Ntn-3 levels in DRGs significantly inhibited the intra-epidermal axon sprouting and alleviated DNP in diabetic mice. In conclusion, our studies identified Ntn-3 as an important regulator of DNP pathogenesis by gating the aberrant sprouting of sensory axons, indicating that Ntn-3 is a potential druggable target for DNP treatment.


Subject(s)
Diabetes Mellitus, Experimental , Diabetic Neuropathies , Neuralgia , Mice , Animals , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Experimental/metabolism , Axons/physiology , Sensory Receptor Cells/metabolism , Neuralgia/metabolism
6.
Cereb Cortex ; 33(7): 3866-3881, 2023 03 21.
Article in English | MEDLINE | ID: mdl-35989311

ABSTRACT

Protein quality control (PQC) is essential for maintaining protein homeostasis and guarding the accuracy of neurodevelopment. Previously, we found that a conserved EBAX-type CRL regulates the protein quality of SAX-3/ROBO guidance receptors in Caenorhabditis elegans. Here, we report that ZSWIM8, the mammalian homolog of EBAX-1, is essential for developmental stability of mammalian brains. Conditional deletion of Zswim8 in the embryonic nervous system causes global cellular stress, partial perinatal lethality and defective migration of neural progenitor cells. CRISPR-mediated knockout of ZSWIM8 impairs spine formation and synaptogenesis in hippocampal neurons. Mechanistic studies reveal that ZSWIM8 controls protein quality of Disabled 1 (Dab1), a key signal molecule for brain development, thus protecting the signaling strength of Dab1. As a ubiquitin ligase enriched with intrinsically disordered regions (IDRs), ZSWIM8 specifically recognizes IDRs of Dab1 through a "disorder targets misorder" mechanism and eliminates misfolded Dab1 that cannot be properly phosphorylated. Adult survivors of ZSWIM8 CKO show permanent hippocampal abnormality and display severely impaired learning and memory behaviors. Altogether, our results demonstrate that ZSWIM8-mediated PQC is critical for the stability of mammalian brain development.


Subject(s)
Reelin Protein , Ubiquitin , Animals , Female , Pregnancy , Cell Adhesion Molecules, Neuronal/metabolism , Extracellular Matrix Proteins/metabolism , Ligases , Mammals/metabolism , Serine Endopeptidases/metabolism , Ubiquitin/metabolism , Ubiquitin-Protein Ligases/metabolism , Adaptor Proteins, Signal Transducing/metabolism , Nerve Tissue Proteins/metabolism
7.
Environ Sci Pollut Res Int ; 29(55): 82729-82739, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36224464

ABSTRACT

To promote the development of the green and low-carbon wood industry and explore the current status and trend of China's used-furniture recycling, this paper summarizes the research status of used-furniture recycling and interprets governmental strategies, such as the development of used-furniture recycling system, the way of handling used-furniture by manufacturers, and the attitudes of customers towards used-furniture, through extensive literature reviews and market research. From such three respects as government, furniture manufacturers, and consumers, the problems of national used-furniture recycling are analyzed, for example, imperfect system, high cost, and weak awareness. Therefore, to solve the above issues, it is necessary to construct national used-furniture recycling system and methods. The government should pay attention to the construction of recycling network, the supervision and support of entrepreneurial responsibilities, and the formulation of recycling standards. For furniture manufacturers, the improvement of the durability and recyclability of furniture and the development of new models and new technologies for furniture recycling and transportation are their primary assignment. And for consumers, the improvements of their concepts of consuming and the environmental protection are in focus. In sum, it aims to provide both suggestions for the amelioration of the measures and methods, and support for the understanding of the change, of used-furniture recycling in China.


Subject(s)
Construction Industry , Recycling , China , Interior Design and Furnishings , Waste Management/methods , Wood
8.
JCI Insight ; 7(22)2022 11 22.
Article in English | MEDLINE | ID: mdl-36194480

ABSTRACT

Neuropathic pain is a refractory condition that involves de novo protein synthesis in the nociceptive pathway. The mTOR is a master regulator of protein translation; however, mechanisms underlying its role in neuropathic pain remain elusive. Using the spared nerve injury-induced neuropathic pain model, we found that mTOR was preferentially activated in large-diameter dorsal root ganglion (DRG) neurons and spinal microglia. However, selective ablation of mTOR in DRG neurons, rather than microglia, alleviated acute neuropathic pain in mice. We show that injury-induced mTOR activation promoted the transcriptional induction of neuropeptide Y (Npy), likely via signal transducer and activator of transcription 3 phosphorylation. NPY further acted primarily on Y2 receptors (Y2R) to enhance neuronal excitability. Peripheral replenishment of NPY reversed pain alleviation upon mTOR removal, whereas Y2R antagonists prevented pain restoration. Our findings reveal an unexpected link between mTOR and NPY/Y2R in promoting nociceptor sensitization and neuropathic pain.


Subject(s)
Neuralgia , Neuropeptide Y , Animals , Mice , Ganglia, Spinal/metabolism , Neuralgia/drug therapy , Neuralgia/metabolism , Neuropeptide Y/metabolism , Nociceptors/metabolism , Receptors, G-Protein-Coupled/metabolism , TOR Serine-Threonine Kinases/metabolism
9.
Sci Transl Med ; 14(639): eabh2557, 2022 04 06.
Article in English | MEDLINE | ID: mdl-35385340

ABSTRACT

Diabetic neuropathic pain (DNP) is a common and devastating complication in patients with diabetes. The mechanisms mediating DNP are not completely elucidated, and effective treatments are lacking. A-fiber sensory neurons have been shown to mediate the development of mechanical allodynia in neuropathic pain, yet the molecular basis underlying the contribution of A-fiber neurons is still unclear. Here, we report that the orphan G protein-coupled receptor 177 (GPR177) in A-fiber neurons drives DNP via WNT5a-mediated activation of transient receptor potential vanilloid receptor-1 (TRPV1) ion channel. GPR177 is mainly expressed in large-diameter A-fiber dorsal root ganglion (DRG) neurons and required for the development of DNP in mice. Mechanistically, we found that GPR177 mediated the secretion of WNT5a from A-fiber DRG neurons into cerebrospinal fluid (CSF), which was necessary for the maintenance of DNP. Extracellular perfusion of WNT5a induced rapid currents in both TRPV1-expressing heterologous cells and nociceptive DRG neurons. Computer simulations revealed that WNT5a has the potential to bind the residues at the extracellular S5-S6 loop of TRPV1. Using a peptide able to disrupt the predicted WNT5a/TRPV1 interaction suppressed DNP- and WNT5a-induced neuropathic pain symptoms in rodents. We confirmed GPR177/WNT5A coexpression in human DRG neurons and WNT5A secretion in CSF from patients with DNP. Thus, our results reveal a role for WNT5a as an endogenous and potent TRPV1 agonist, and the GPR177-WNT5a-TRPV1 axis as a driver of DNP pathogenesis in rodents. Our findings identified a potential analgesic target that might relieve neuropathic pain in patients with diabetes.


Subject(s)
Diabetes Mellitus , Diabetic Neuropathies , Intracellular Signaling Peptides and Proteins , Neuralgia , Receptors, G-Protein-Coupled , TRPV Cation Channels , Wnt-5a Protein , Animals , Diabetes Mellitus/metabolism , Diabetic Neuropathies/metabolism , Ganglia, Spinal/metabolism , Humans , Intracellular Signaling Peptides and Proteins/metabolism , Mice , Neuralgia/metabolism , Receptors, G-Protein-Coupled/metabolism , Sensory Receptor Cells/metabolism , TRPV Cation Channels/metabolism , Wnt-5a Protein/metabolism
10.
Adv Sci (Weinh) ; 8(22): e2101717, 2021 11.
Article in English | MEDLINE | ID: mdl-34658162

ABSTRACT

Platinum-based compounds in chemotherapy such as oxaliplatin often induce peripheral neuropathy and neuropathic pain such as cold allodynia in patients. Transient Receptor Potential Melastatin 8 (TRPM8) ion channel is a nociceptor critically involved in such pathological processes. Direct blockade of TRPM8 exhibits significant analgesic effects but also incurs severe side effects such as hypothermia. To selectively target TRPM8 channels against cold allodynia, a cyclic peptide DeC-1.2 is de novo designed with the optimized hot-spot centric approach. DeC-1.2 modality specifically inhibited the ligand activation of TRPM8 but not the cold activation as measured in single-channel patch clamp recordings. It is further demonstrated that DeC-1.2 abolishes cold allodynia in oxaliplatin treated mice without altering body temperature, indicating DeC-1.2 has the potential for further development as a novel analgesic against oxaliplatin-induced neuropathic pain.


Subject(s)
Antineoplastic Agents/adverse effects , Hyperalgesia/prevention & control , Oxaliplatin/adverse effects , TRPM Cation Channels/antagonists & inhibitors , TRPM Cation Channels/genetics , Animals , Antineoplastic Agents/metabolism , Cold Temperature , Hyperalgesia/chemically induced , Hyperalgesia/metabolism , Male , Mice , Oxaliplatin/metabolism , TRPM Cation Channels/metabolism
11.
Brain ; 144(11): 3405-3420, 2021 12 16.
Article in English | MEDLINE | ID: mdl-34244727

ABSTRACT

Neuropathic pain is a major health problem that affects up to 7-10% of the population worldwide. Currently, neuropathic pain is difficult to treat because of its elusive mechanisms. Here we report that orphan G protein-coupled receptor 151 (GPR151) in nociceptive sensory neurons controls neuropathic pain induced by nerve injury. GPR151 was mainly expressed in non-peptidergic C-fibre dorsal root ganglion neurons and highly upregulated after nerve injury. Importantly, conditional knockout of Gpr151 in adult nociceptive sensory neurons significantly alleviated chronic constriction injury-induced neuropathic pain-like behaviour but did not affect basal nociception. Moreover, GPR151 in DRG neurons was required for chronic constriction injury-induced neuronal hyperexcitability and upregulation of colony-stimulating factor 1 (CSF1), which is necessary for microglial activation in the spinal cord after nerve injury. Mechanistically, GPR151 coupled with P2X3 ion channels and promoted their functional activities in neuropathic pain-like hypersensitivity. Knockout of Gpr151 suppressed P2X3-mediated calcium elevation and spontaneous pain behaviour in chronic constriction injury mice. Conversely, overexpression of Gpr151 significantly enhanced P2X3-mediated calcium elevation and dorsal root ganglion neuronal excitability. Furthermore, knockdown of P2X3 in dorsal root ganglia reversed chronic constriction injury-induced CSF1 upregulation, spinal microglial activation and neuropathic pain-like behaviour. Finally, the coexpression of GPR151 and P2X3 was confirmed in small-diameter human dorsal root ganglion neurons, indicating the clinical relevance of our findings. Together, our results indicate that GPR151 in nociceptive dorsal root ganglion neurons plays a key role in the pathogenesis of neuropathic pain and could be a potential target for treating neuropathic pain.


Subject(s)
Microglia/metabolism , Neuralgia/metabolism , Nociceptors/metabolism , Receptors, G-Protein-Coupled/metabolism , Receptors, Purinergic P2X3/metabolism , Animals , Ganglia, Spinal/metabolism , Humans , Male , Mice , Mice, Inbred C57BL
13.
Neurosci Bull ; 37(7): 1079-1081, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33929705
14.
Proc Natl Acad Sci U S A ; 118(7)2021 02 16.
Article in English | MEDLINE | ID: mdl-33563763

ABSTRACT

Sociability is fundamental for our daily life and is compromised in major neuropsychiatric disorders. However, the neuronal circuit mechanisms underlying prosocial behavior are still elusive. Here we identify a causal role of the basal forebrain (BF) in the control of prosocial behavior via inhibitory projections that disinhibit the midbrain ventral tegmental area (VTA) dopamine (DA) neurons. Specifically, BF somatostatin-positive (SST) inhibitory neurons were robustly activated during social interaction. Optogenetic inhibition of these neurons in BF or their axon terminals in the VTA largely abolished social preference. Electrophysiological examinations further revealed that SST neurons predominantly targeted VTA GABA neurons rather than DA neurons. Consistently, optical inhibition of SST neuron axon terminals in the VTA decreased DA release in the nucleus accumbens during social interaction, confirming a disinhibitory action. These data reveal a previously unappreciated function of the BF in prosocial behavior through a disinhibitory circuitry connected to the brain's reward system.


Subject(s)
Dopaminergic Neurons/physiology , Prosencephalon/physiology , Social Behavior , Ventral Tegmental Area/physiology , Animals , Dopaminergic Neurons/metabolism , GABAergic Neurons/metabolism , GABAergic Neurons/physiology , Male , Mice , Neural Inhibition , Prosencephalon/cytology , Reward , Somatostatin/genetics , Somatostatin/metabolism , Ventral Tegmental Area/cytology
15.
Cell Rep ; 29(8): 2384-2397.e5, 2019 11 19.
Article in English | MEDLINE | ID: mdl-31747607

ABSTRACT

The proinflammatory cytokine interleukin-17 (IL-17) is implicated in pain regulation. However, the synaptic mechanisms by which IL-17 regulates pain transmission are unknown. Here, we report that glia-produced IL-17 suppresses inhibitory synaptic transmission in the spinal cord pain circuit and drives chemotherapy-induced neuropathic pain. We find that IL-17 not only enhances excitatory postsynaptic currents (EPSCs) but also suppresses inhibitory postsynaptic synaptic currents (IPSCs) and GABA-induced currents in lamina IIo somatostatin-expressing neurons in mouse spinal cord slices. IL-17 mainly expresses in spinal cord astrocytes, and its receptor IL-17R is detected in somatostatin-expressing neurons. Selective knockdown of IL-17R in spinal somatostatin-expressing interneurons reduces paclitaxel-induced hypersensitivity. Overexpression of IL-17 in spinal astrocytes is sufficient to induce mechanical allodynia in naive animals. In dorsal root ganglia, IL-17R expression in nociceptive sensory neurons is sufficient and required for inducing neuronal hyperexcitability after paclitaxel. Together, our data show that IL-17/IL-17R mediate neuron-glial interactions and neuronal hyperexcitability in chemotherapy-induced peripheral neuropathy.


Subject(s)
Interleukin-17/metabolism , Neuralgia/metabolism , Synaptic Transmission/physiology , Animals , Astrocytes/drug effects , Astrocytes/metabolism , Excitatory Postsynaptic Potentials/drug effects , Excitatory Postsynaptic Potentials/physiology , Humans , Neuralgia/physiopathology , Neuroglia/drug effects , Neuroglia/metabolism , Neurons/drug effects , Neurons/metabolism , Peripheral Nervous System Diseases/metabolism , Somatostatin/metabolism , Synaptic Transmission/drug effects , gamma-Aminobutyric Acid/pharmacology
16.
J Neurosci ; 39(31): 6202-6215, 2019 07 31.
Article in English | MEDLINE | ID: mdl-31152125

ABSTRACT

Mechanical allodynia is a cardinal feature of pathological pain. Recent work has demonstrated the necessity of Aß-low-threshold mechanoreceptors (Aß-LTMRs) for mechanical allodynia-like behaviors in mice, but it remains unclear whether these neurons are sufficient to produce pain under pathological conditions. We generated a transgenic mouse in which channelrhodopsin-2 (ChR2) is conditionally expressed in vesicular glutamate transporter 1 (Vglut1) sensory neurons (Vglut1-ChR2), which is a heterogeneous population of large-sized sensory neurons with features consistent with Aß-LTMRs. In naive male Vglut1-ChR2 mice, transdermal hindpaw photostimulation evoked withdrawal behaviors in an intensity- and frequency-dependent manner, which were abolished by local anesthetic and selective A-fiber blockade. Surprisingly, male Vglut1-ChR2 mice did not show significant differences in light-evoked behaviors or real-time aversion after nerve injury despite marked hypersensitivity to punctate mechanical stimuli. We conclude that optogenetic activation of cutaneous Vglut1-ChR2 neurons alone is not sufficient to produce pain-like behaviors in neuropathic mice.SIGNIFICANCE STATEMENT Mechanical allodynia, in which innocuous touch is perceived as pain, is a common feature of pathological pain. To test the contribution of low-threshold mechanoreceptors (LTMRs) to nerve-injury-induced mechanical allodynia, we generated and characterized a new transgenic mouse (Vglut1-ChR2) to optogenetically activate cutaneous vesicular glutamate transporter 1 (Vglut1)-positive LTMRs. Using this mouse, we found that light-evoked behaviors were unchanged by nerve injury, which suggests that activation of Vglut1-positive LTMRs alone is not sufficient to produce pain. The Vglut1-ChR2 mouse will be broadly useful for the study of touch, pain, and itch.


Subject(s)
Hyperalgesia/physiopathology , Mechanoreceptors/physiology , Neuralgia/physiopathology , Sensory Receptor Cells/physiology , Vesicular Glutamate Transport Protein 1/metabolism , Animals , Female , Male , Mice , Mice, Transgenic , Optogenetics/methods , Peripheral Nerve Injuries
17.
J Clin Invest ; 128(8): 3568-3582, 2018 08 01.
Article in English | MEDLINE | ID: mdl-30010619

ABSTRACT

The mechanisms of pain induction by inflammation have been extensively studied. However, the mechanisms of pain resolution are not fully understood. Here, we report that GPR37, expressed by macrophages (MΦs) but not microglia, contributes to the resolution of inflammatory pain. Neuroprotectin D1 (NPD1) and prosaptide TX14 increase intracellular Ca2+ (iCa2+) levels in GPR37-transfected HEK293 cells. NPD1 and TX14 also bind to GPR37 and cause GPR37-dependent iCa2+ increases in peritoneal MΦs. Activation of GPR37 by NPD1 and TX14 triggers MΦ phagocytosis of zymosan particles via calcium signaling. Hind paw injection of pH-sensitive zymosan particles not only induces inflammatory pain and infiltration of neutrophils and MΦs, but also causes GPR37 upregulation in MΦs, phagocytosis of zymosan particles and neutrophils by MΦs in inflamed paws, and resolution of inflammatory pain in WT mice. Mice lacking Gpr37 display deficits in MΦ phagocytic activity and delayed resolution of inflammatory pain. Gpr37-deficient MΦs also show dysregulations of proinflammatory and antiinflammatory cytokines. MΦ depletion delays the resolution of inflammatory pain. Adoptive transfer of WT but not Gpr37-deficient MΦs promotes the resolution of inflammatory pain. Our findings reveal a previously unrecognized role of GPR37 in regulating MΦ phagocytosis and inflammatory pain resolution.


Subject(s)
Macrophages, Peritoneal/immunology , Pain/immunology , Phagocytosis , Receptors, G-Protein-Coupled/immunology , Animals , Docosahexaenoic Acids/genetics , Docosahexaenoic Acids/immunology , HEK293 Cells , Humans , Inflammation/chemically induced , Inflammation/genetics , Inflammation/immunology , Inflammation/pathology , Macrophages, Peritoneal/pathology , Mice , Mice, Knockout , Neutrophils/immunology , Neutrophils/pathology , Pain/chemically induced , Pain/genetics , Pain/pathology , Receptors, G-Protein-Coupled/genetics , Up-Regulation , Zymosan/toxicity
18.
Front Pharmacol ; 9: 412, 2018.
Article in English | MEDLINE | ID: mdl-29765320

ABSTRACT

Mechanisms of pain resolution are largely unclear. Increasing evidence suggests that specialized pro-resolving mediators (SPMs), derived from fish oil docosahexaenoic acid (DHA), promote the resolution of acute inflammation and potently inhibit inflammatory and neuropathic pain. In this study, we examined the analgesic impact of DHA and DHA-derived SPMs in a mouse model of post-operative pain induced by tibial bone fracture (fPOP). Intravenous perioperative treatment with DHA (500 µg), resolvin D1 (RvD1, 500 ng) and maresin 1 (MaR1, 500 ng), 10 min and 24 h after the surgery, delayed the development of fPOP (mechanical allodynia and cold allodynia). In contrast, post-operative intrathecal (IT) administration of DHA (500 µg) 2 weeks after the surgery had no effects on established mechanical and cold allodynia. However, by direct comparison, IT post-operative treatment (500 ng) with neuroprotectin D1 (NPD1), MaR1, and D-resolvins, RvD1 and RvD5, but not RvD3 and RvD4, effectively reduced mechanical and cold allodynia. ELISA analysis showed that perioperative DHA treatment increased RvD1 levels in serum and spinal cord samples after bone fracture. Interestingly, sham surgery resulted in transient allodynia and increased RvD1 levels, suggesting a correlation of enhanced SPM levels with acute pain resolution after sham surgery. Our findings suggest that (1) perioperative treatment with DHA is effective in preventing and delaying the development of fPOP and (2) post-treatment with some SPMs can attenuate established fPOP. Our data also indicate that orthopedic surgery impairs SPM production. Thus, DHA and DHA-derived SPMs should be differentially supplemented for treating fPOP and improving recovery.

19.
Entropy (Basel) ; 20(12)2018 Dec 03.
Article in English | MEDLINE | ID: mdl-33266647

ABSTRACT

The purpose of this paper is to predict failures based on textual sequence data. The current failure prediction is mainly based on structured data. However, there are many unstructured data in aircraft maintenance. The failure mentioned here refers to failure types, such as transmitter failure and signal failure, which are classified by the clustering algorithm based on the failure text. For the failure text, this paper uses the natural language processing technology. Firstly, segmentation and the removal of stop words for Chinese failure text data is performed. The study applies the word2vec moving distance model to obtain the failure occurrence sequence for failure texts collected in a fixed period of time. According to the distance, a clustering algorithm is used to obtain a typical number of fault types. Secondly, the failure occurrence sequence is mined using sequence mining algorithms, such as-PrefixSpan. Finally, the above failure sequence is used to train the Bayesian failure network model. The final experimental results show that the Bayesian failure network has higher accuracy for failure prediction.

20.
Sci Rep ; 6: 34356, 2016 Sep 27.
Article in English | MEDLINE | ID: mdl-27670299

ABSTRACT

It is well known that interferons (IFNs), such as type-I IFN (IFN-α) and type-II IFN (IFN-γ) are produced by immune cells to elicit antiviral effects. IFNs are also produced by glial cells in the CNS to regulate brain functions. As a proinflammatory cytokine, IFN-γ drives neuropathic pain by inducing microglial activation in the spinal cord. However, little is known about the role of IFN-α in regulating pain sensitivity and synaptic transmission. Strikingly, we found that IFN-α/ß receptor (type-I IFN receptor) was expressed by primary afferent terminals in the superficial dorsal horn that co-expressed the neuropeptide CGRP. In the spinal cord IFN-α was primarily expressed by astrocytes. Perfusion of spinal cord slices with IFN-α suppressed excitatory synaptic transmission by reducing the frequency of spontaneous excitatory postsynaptic current (sEPSCs). IFN-α also inhibited nociceptive transmission by reducing capsaicin-induced internalization of NK-1 and phosphorylation of extracellular signal-regulated kinase (ERK) in superficial dorsal horn neurons. Finally, spinal (intrathecal) administration of IFN-α reduced inflammatory pain and increased pain threshold in naïve rats, whereas removal of endogenous IFN-α by a neutralizing antibody induced hyperalgesia. Our findings suggest a new form of neuronal-glial interaction by which IFN-α, produced by astrocytes, inhibits nociceptive transmission in the spinal cord.

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