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The role of spinal neurons targeted by corticospinal neurons in central poststroke neuropathic pain.CNS Neuroscience & Therapeutics Jun 2024Central poststroke pain (CPSP) is one of the primary sequelae following stroke, yet its underlying mechanisms are poorly understood.
BACKGROUND
Central poststroke pain (CPSP) is one of the primary sequelae following stroke, yet its underlying mechanisms are poorly understood.
METHODS
By lesioning the lateral thalamic nuclei, we first established a CPSP model that exhibits mechanical and thermal hypersensitivity. Innocuous mechanical stimuli following the thalamic lesion evoked robust neural activation in somatosensory corticospinal neurons (CSNs), as well as in the deep dorsal horn, where low threshold mechanosensory afferents terminate. In this study, we used viral-based mapping and intersectional functional manipulations to decipher the role of somatosensory CSNs and their spinal targets in the CPSP pathophysiology.
RESULTS
We first mapped the post-synaptic spinal targets of lumbar innervating CSNs using an anterograde trans-synaptic AAV1-based strategy and showed these spinal interneurons were activated by innocuous tactile stimuli post-thalamic lesion. Functionally, tetanus toxin-based chronic inactivation of spinal neurons targeted by CSNs prevented the development of CPSP. Consistently, transient chemogenetic silencing of these neurons alleviated established mechanical pain hypersensitivity and innocuous tactile stimuli evoked aversion linked to the CPSP. In contrast, chemogenetic activation of these neurons was insufficient to induce robust mechanical allodynia typically observed in the CPSP.
CONCLUSION
The CSNs and their spinal targets are required but insufficient for the establishment of CPSP hypersensitivity. Our study provided novel insights into the neural mechanisms underlying CPSP and potential therapeutic interventions to treat refractory central neuropathic pain conditions.
Topics: Animals; Neuralgia; Pyramidal Tracts; Male; Stroke; Neurons; Hyperalgesia; Rats, Sprague-Dawley; Rats; Disease Models, Animal; Spinal Cord
PubMed: 38887838
DOI: 10.1111/cns.14813 -
Cureus May 2024The COVID-19 pandemic caused by the coronavirus SARS-CoV-2 revealed a huge number of problems as well as discoveries in medicine, notably, regarding the effects of the... (Review)
Review
The COVID-19 pandemic caused by the coronavirus SARS-CoV-2 revealed a huge number of problems as well as discoveries in medicine, notably, regarding the effects of the virus on the central nervous system (CNS) and peripheral nervous system (PNS). This paper is a narrative review that takes a deep dive into the complex interactions between COVID-19 and the NS. Therefore, this paper explains the broad range of neurological manifestations and neurodegenerative diseases caused by the virus. It carefully considers the routes through which SARS-CoV-2 reaches the NS, including the olfactory system and of course, the hematogenous route, which are also covered when discussing the virus's direct and indirect mechanisms of neuropathogenesis. Besides neurological pathologies such as stroke, encephalitis, Guillain-Barré syndrome, Parkinson's disease, and multiple sclerosis, the focus area is also given to the challenges of making diagnosis, treatment, and management of these conditions during the pandemic. The review also examines the strategic and interventional approaches utilized to prevent these disorders, as well as the ACE2 receptors implicated in the mediation of neurological effects caused by COVID-19. This detailed overview, which combines research outputs with case data, is directed at tackling this pandemic challenge, with a view toward better patient care and outcomes in the future.
PubMed: 38887342
DOI: 10.7759/cureus.60376 -
Neural Regeneration Research Mar 2025Mononuclear macrophage infiltration in the central nervous system is a prominent feature of neuroinflammation. Recent studies on the pathogenesis and progression of...
Mononuclear macrophage infiltration in the central nervous system is a prominent feature of neuroinflammation. Recent studies on the pathogenesis and progression of multiple sclerosis have highlighted the multiple roles of mononuclear macrophages in the neuroinflammatory process. Monocytes play a significant role in neuroinflammation, and managing neuroinflammation by manipulating peripheral monocytes stands out as an effective strategy for the treatment of multiple sclerosis, leading to improved patient outcomes. This review outlines the steps involved in the entry of myeloid monocytes into the central nervous system that are targets for effective intervention: the activation of bone marrow hematopoiesis, migration of monocytes in the blood, and penetration of the blood-brain barrier by monocytes. Finally, we summarize the different monocyte subpopulations and their effects on the central nervous system based on phenotypic differences. As activated microglia resemble monocyte-derived macrophages, it is important to accurately identify the role of monocyte-derived macrophages in disease. Depending on the roles played by monocyte-derived macrophages at different stages of the disease, several of these processes can be interrupted to limit neuroinflammation and improve patient prognosis. Here, we discuss possible strategies to target monocytes in neurological diseases, focusing on three key aspects of monocyte infiltration into the central nervous system, to provide new ideas for the treatment of neurodegenerative diseases.
PubMed: 38886942
DOI: 10.4103/NRR.NRR-D-23-01508 -
Acta Neuropathologica Communications Jun 2024Filaments made of residues 120-254 of transmembrane protein 106B (TMEM106B) form in an age-dependent manner and can be extracted from the brains of neurologically normal...
Filaments made of residues 120-254 of transmembrane protein 106B (TMEM106B) form in an age-dependent manner and can be extracted from the brains of neurologically normal individuals and those of subjects with a variety of neurodegenerative diseases. TMEM106B filament formation requires cleavage at residue 120 of the 274 amino acid protein; at present, it is not known if residues 255-274 form the fuzzy coat of TMEM106B filaments. Here we show that a second cleavage appears likely, based on staining with an antibody raised against residues 263-274 of TMEM106B. We also show that besides the brain TMEM106B inclusions form in dorsal root ganglia and spinal cord, where they were mostly found in non-neuronal cells. We confirm that in the brain, inclusions were most abundant in astrocytes. No inclusions were detected in heart, liver, spleen or hilar lymph nodes. Based on their staining with luminescent conjugated oligothiophenes, we confirm that TMEM106B inclusions are amyloids. By in situ immunoelectron microscopy, TMEM106B assemblies were often found in structures resembling endosomes and lysosomes.
Topics: Membrane Proteins; Humans; Nerve Tissue Proteins; Spinal Cord; Amyloid; Ganglia, Spinal; Brain; Male; Female; Peripheral Nervous System; Aged; Animals
PubMed: 38886865
DOI: 10.1186/s40478-024-01813-z -
Journal of Nanobiotechnology Jun 2024Molybdenum disulfide (MoS) has excellent physical and chemical properties. Further, chiral MoS (CMS) exhibits excellent chiroptical and enantioselective effects, and the...
BACKGROUND
Molybdenum disulfide (MoS) has excellent physical and chemical properties. Further, chiral MoS (CMS) exhibits excellent chiroptical and enantioselective effects, and the enantioselective properties of CMS have been studied for the treatment of neurodegenerative diseases. Intriguingly, left- and right-handed materials have different effects on promoting the differentiation of neural stem cells into neurons. However, the effect of the enantioselectivity of chiral materials on peripheral nerve regeneration remains unclear.
METHODS
In this study, CMS@bacterial cellulose (BC) scaffolds were fabricated using a hydrothermal approach. The CMS@BC films synthesized with L-2-amino-3-phenyl-1-propanol was defined as L-CMS. The CMS@BC films synthesized with D-2-amino-3-phenyl-1-propanol was defined as D-CMS. The biocompatibility of CMS@BC scaffolds and their effect on Schwann cells (SCs) were validated by cellular experiments. In addition, these scaffolds were implanted in rat sciatic nerve defect sites for three months.
RESULTS
These chiral scaffolds displayed high hydrophilicity, good mechanical properties, and low cytotoxicity. Further, we found that the L-CMS scaffolds were superior to the D-CMS scaffolds in promoting SCs proliferation. After three months, the scaffolds showed good biocompatibility in vivo, and the nerve conducting velocities of the L-CMS and D-CMS scaffolds were 51.2 m/s and 26.8 m/s, respectively. The L-CMS scaffolds showed a better regenerative effect than the D-CMS scaffolds. Similarly, the sciatic nerve function index and effects on the motor and electrophysiological functions were higher for the L-CMS scaffolds than the D-CMS scaffolds. Finally, the axon diameter and myelin sheath thickness of the regenerated nerves were improved in the L-CMS group.
CONCLUSION
We found that the CMS@BC can promote peripheral nerve regeneration, and in general, the L-CMS group exhibited superior repair performance. Overall, the findings of this study reveal that CMS@BC can be used as a chiral nanomaterial nerve scaffold for peripheral nerve repair.
Topics: Nerve Regeneration; Animals; Rats; Tissue Scaffolds; Disulfides; Schwann Cells; Molybdenum; Cellulose; Rats, Sprague-Dawley; Biocompatible Materials; Sciatic Nerve; Cell Proliferation; Tissue Engineering; Male; Peripheral Nerve Injuries; Stereoisomerism
PubMed: 38886712
DOI: 10.1186/s12951-024-02493-6 -
Journal of the American Academy of... Jun 2024This study compared trends in use, predictive factors, and reimbursement of endoscopic carpal tunnel release (ECTR) withthose of open carpal tunnel release (OCTR) from... (Comparative Study)
Comparative Study
BACKGROUND
This study compared trends in use, predictive factors, and reimbursement of endoscopic carpal tunnel release (ECTR) withthose of open carpal tunnel release (OCTR) from 2010 to 2021 using a national administrative database.
METHODS
ECTR and OCTR patients were identified in the PearlDiver M151Ortho data set. Numeric and proportional utilization of these procedures was characterized for each year of study. Multivariate analysis was conducted to identify predictive factors for having ECTR performed. The average 90-day reimbursement of ECTR and OCTR was determined.
RESULTS
From 2010 through 2021, 441,023 ECTR and 1,767,820 OCTR procedures were identified. The proportional use of ECTR compared with OCTR rose from 2010 (15.7% of procedures) to 2021 (26.1%). Independent predictors of having ECTR performed rather than OCTR included geographic variation (compared with having surgery in the Midwest, Northeast odds ratio [OR], 1.53; West OR, 1.62; and South OR, 1.66), having Medicare or commercial insurance (compared with commercial, Medicare OR, 0.94, and Medicaid OR, 0.69), female sex, and fewer comorbidities. The average 90-day reimbursement for ECTR was $3,114.82, compared with $3,087.62 for OCTR.
DISCUSSION
As of 2021, over one-fourth of carpal tunnel releases are done endoscopically. Several factors independently predict whether patients receive ECTR or OCTR.
Topics: Humans; Carpal Tunnel Syndrome; Female; Male; Middle Aged; Endoscopy; Aged; United States; Adult; Decompression, Surgical; Databases, Factual; Medicare
PubMed: 38885416
DOI: 10.5435/JAAOSGlobal-D-24-00077 -
Aging Cell Jun 2024Mitochondria are dynamic bioenergetic hubs that become compromised with age. In neurons, declining mitochondrial axonal transport has been associated with reduced...
Mitochondria are dynamic bioenergetic hubs that become compromised with age. In neurons, declining mitochondrial axonal transport has been associated with reduced cellular health. However, it is still unclear to what extent the decline of mitochondrial transport and function observed during ageing are coupled, and if somal and axonal mitochondria display compartment-specific features that make them more susceptible to the ageing process. It is also not known whether the biophysical state of the cytoplasm, thought to affect many cellular functions, changes with age to impact mitochondrial trafficking and homeostasis. Focusing on the mouse peripheral nervous system, we show that age-dependent decline in mitochondrial trafficking is accompanied by reduction of mitochondrial membrane potential and intramitochondrial viscosity, but not calcium buffering, in both somal and axonal mitochondria. Intriguingly, we observe a specific increase in cytoplasmic viscosity in the neuronal cell body, where mitochondria are most polarised, which correlates with decreased cytoplasmic diffusiveness. Increasing cytoplasmic crowding in the somatic compartment of DRG neurons grown in microfluidic chambers reduces mitochondrial axonal trafficking, suggesting a mechanistic link between the regulation of cytoplasmic viscosity and mitochondrial dynamics. Our work provides a reference for studying the relationship between neuronal mitochondrial homeostasis and the viscoelasticity of the cytoplasm in a compartment-dependent manner during ageing.
PubMed: 38881280
DOI: 10.1111/acel.14250 -
The Lancet. Infectious Diseases Jun 2024In 2020, WHO guidelines prioritised the use of a standard fully oral short treatment regimen (STR) consisting of bedaquiline, levofloxacin or moxifloxacin, ethionamide,...
BACKGROUND
In 2020, WHO guidelines prioritised the use of a standard fully oral short treatment regimen (STR) consisting of bedaquiline, levofloxacin or moxifloxacin, ethionamide, ethambutol, high-dose isoniazid, pyrazinamide, and clofazimine for the management of rifampicin-resistant tuberculosis. A high prevalence of resistance to constituent drugs precluded its widespread use by countries in the WHO European region. We evaluated three 9-month fully oral modified STRs (mSTRs) in which ethionamide, ethambutol, isoniazid, and pyrazinamide were replaced by linezolid, cycloserine, or delamanid (or a combination).
METHODS
This multicountry, prospective, single-arm, cohort study examined the effectiveness and safety of mSTRs for fluoroquinolone-susceptible, rifampicin-resistant pulmonary tuberculosis in 13 countries in the WHO European region during 2020-23. We enrolled adults and children of all ages with bacteriologically confirmed rifampicin-resistant, fluoroquinolone-susceptible pulmonary tuberculosis, and children (aged 0-18 years) with clinically diagnosed disease and a confirmed contact with rifampicin-resistant, fluoroquinolone-susceptible tuberculosis. Participants aged 6 years or older received one of two regimens: bedaquiline, linezolid, levofloxacin, clofazimine, and cycloserine; or bedaquiline, linezolid, levofloxacin, clofazimine, and delamanid. Children younger than 6 years received delamanid, linezolid, levofloxacin, and clofazimine. Participants were followed up for 12 months after successful treatment completion to detect recurrence and death. The primary outcome was the cumulative probability of not having an unsuccessful study outcome (defined as treatment failure, on-treatment loss to follow-up, death, or recurrence) before 22 months of study follow-up. The primary safety outcome was the incidence of each adverse event of interest (peripheral neuropathy, optic neuritis, myelosuppression, hepatitis, prolonged QT interval, hypokalaemia, and acute kidney injury) of grade 3 or higher severity during the treatment course.
FINDINGS
Between Aug 28, 2020 and May 26, 2021, 7272 patients were screened and 2636 were included in the treatment cohort. 1966 (74·6%) were male, 670 (25·4%) were female, and median age was 43 years (IQR 33-53). Treatment success was recorded for 2181 (82·7%) participants. The cumulative probability of not having an unsuccessful study outcome 22 months after treatment initiation was 79% (95% CI 78-81). Increasing age (adjusted hazard ratio 2·61 [95% CI 1·70-4·04] for people aged >64 years vs 35-44 years), HIV-positive status (1·53 [1·16-2·01]), presence of bilateral cavities (1·68 [1·29-2·19]), smoking history (1·34 [1·05-1·71]), baseline anaemia (1·46 [1·15-1·86]), unemployment (1·37 [1·04-1·80]), elevated baseline liver enzymes (1·40 [1·13-1·73]), and excessive alcohol use (1·47 [1·14-1·89]) were positively associated with unsuccessful study outcomes. In the safety cohort of 2813 participants who received at least one dose, 301 adverse events of interest were recorded in 252 (9·0%) participants with the most frequent being myelosuppression (139 [4·9%] participants, 157 [52·2%] events).
INTERPRETATION
The high treatment success and good safety results indicate considerable potential for the use of mSTRs in programmatic conditions, especially for individuals not eligible for the current WHO-recommended 6-month regimen and in settings with a need for alternative options.
FUNDING
The Global Fund to Fight AIDS, Tuberculosis and Malaria; United States Agency for International Development; Government of Germany; and WHO.
TRANSLATION
For the Russian translation of the abstract see Supplementary Materials section.
PubMed: 38880112
DOI: 10.1016/S1473-3099(24)00228-7 -
The American Journal of Case Reports Jun 2024BACKGROUND Compression of the vagus nerve by a pharyngeal mass is a well-documented condition that can result in sinus node dysfunction (SND). However, there is scarce...
BACKGROUND Compression of the vagus nerve by a pharyngeal mass is a well-documented condition that can result in sinus node dysfunction (SND). However, there is scarce literature on extrinsic vagal nerve compression from a tonsillar abscess. CASE REPORT A 59-year-old woman with a history of asthma and chronic throat discomfort presented to the Emergency Department with bradycardia, palpitations, and voice changes. Following a shellfish allergy hospitalization, an otolaryngology evaluation revealed an enlarged right tonsil, recommending tonsillectomy, but scheduling challenges persisted. The patient reported mild throat pain, dysphagia, hoarseness, rhinorrhea, and exertional dyspnea and was admitted for the evaluation of peritonsillar mass. She was found to be bradycardic with a heart rate of 47, with an electrocardiogram revealing SND. Albuterol and ipratropium nebulizers, as well as dexamethasone and pantoprazole, were initiated. With this treatment, the patient symptomatically improved with a new heart rate of 68. She was discharged with outpatient appointments, but was unfortunately lost to follow-up. CONCLUSIONS This case reveals sinus node dysfunction resulting from extrinsic vagal nerve compression by a tonsillar abscess. Pressure on the vagus nerve can trigger bradycardia and low blood pressure, possibly due to compensatory overfiring of afferent vagal nerve signals from local mass effect. Early recognition and antibiotic treatment are essential to prevent cardiac complications. Clinicians must remain vigilant for such extrinsic causes, particularly in patients with chronic sore throat and cardiac symptoms. Further research and case reports are needed to deepen our understanding of this rare yet significant association.
Topics: Humans; Female; Middle Aged; Sick Sinus Syndrome; Peritonsillar Abscess; Nerve Compression Syndromes; Vagus Nerve
PubMed: 38879750
DOI: 10.12659/AJCR.943944 -
Scientific Reports Jun 2024Creatine kinase (CK) has been associated with neuropathy, but the mechanisms are uncertain. We hypothesized that peripheral nerve function is impaired in subjects with...
Creatine kinase (CK) has been associated with neuropathy, but the mechanisms are uncertain. We hypothesized that peripheral nerve function is impaired in subjects with persistent CK elevation (hyperCKemia) compared to age- and sex matched controls in a general population. The participants were recruited from the population based Tromsø study in Norway. Neuropathy impairment score (NIS), nerve conduction studies (NCS) and electromyography (EMG) in subjects with persistent hyperCKemia (n = 113; 51 men, 62 women) and controls (n = 128; 61 men, 67 women) were performed. The hyperCKemia group had higher NIS score than the controls (p = 0.050). NCS of the tibial nerve showed decreased compound motor action potential amplitude (p < 0.001), decreased motor conduction velocity (p < 0.001) and increased F-wave latency (p = 0.044). Also, reduced sensory amplitudes of the median, ulnar, and sural nerves were found. EMG showed significantly increased average motor unit potential amplitude in all examined muscles. CK correlated positively with glycated hemoglobin and non-fasting glucose in the hyperCKemia group, although not when controlled for covariates. The length dependent polyneuropathy demonstrated in the hyperCKemia group is unexplained, but CK leakage and involvement of glucose metabolism are speculated on.
Topics: Humans; Male; Female; Creatine Kinase; Polyneuropathies; Case-Control Studies; Aged; Neural Conduction; Middle Aged; Electromyography; Norway
PubMed: 38879579
DOI: 10.1038/s41598-024-64555-x