Movement Disturbances Research Articles

Imaging Glucose Metabolism and Dopaminergic Dysfunction in Sheep (Ovis aries) Brain Using Positron Emission Tomography Imaging Reveals Abnormalities in OVT73 Huntington's Disease Sheep.

Huntington's disease (HD) is a neurodegenerative disease that causes cognitive, movement, behavioral, and sleep disturbances, which over time result in progressive disability and eventually death. Clinical translation of novel therapeutics and imaging probes could be accelerated by additional testing in well-characterized large animal models of HD. The major goal of our preliminary cross-sectional study is to demonstrate the feasibility and utility of the unique transgenic sheep model of HD (OVT73) in positron emission tomography (PET) imaging. PET imaging studies were performed in healthy merino sheep (6 year old, n = 3) and OVT73 HD sheep (5.5 year old, n = 3, and 11 year old, n = 3). Region-of-interest and brain atlas labels were defined for regional analyses by using a sheep brain template. [18F]fluorodeoxyglucose ([18F]FDG) was employed to compare the regional brain glucose metabolism and variations in FDG uptake between control and HD sheep. We also used [18F]fluoro-3,4-dihydroxyphenylalanine ([18F]FDOPA) to compare the extent of striatal dysfunction and evaluated the binding potential (BPND) in key brain regions between the groups. Compared with healthy controls and 11 year old HD sheep, the 5.5 year old HD sheep exhibited significantly increased [18F]FDG uptake in several cortical and subcortical brain regions (P < 0.05-0.01). No difference in [18F]FDG uptake was observed between healthy controls and 11 year old HD sheep. Analysis of the [18F]FDOPA BPND parametric maps revealed clusters of reduced binding potential in the 5.5 year old and 11 year old HD sheep compared to the 6 year old control sheep. In this first-of-its-kind study, we showed the usefulness and validity of HD sheep model in imaging cerebral glucose metabolism and dopamine uptake using PET imaging. The identification of discrete patterns of metabolic abnormality using [18F]FDG and decline of [18F]FDOPA uptake may provide a useful means of quantifying early HD-related changes in these models, particularly in the transition from presymptomatic to early symptomatic phases of HD.

A Review of Hemodynamic Parameters in Cerebral Aneurysm

Abstract—A cerebral aneurysm is a localized dilation that weakens the wall of a blood vessel in the brain. This condition comes in the form of abnormal widening, ballooning or in the form of a bleb. Gaining an understanding of the initiation, growth, and rupture of cerebral aneurysm has played a critical role in finding treatments that prevent the possibility of mortality and morbidity. Cerebral aneurysm develops as a result of the thinning of artery wall, and it is often difficult to diagnose prior to its rupture that leads to several fatal diseases, including brain damage, hemorrhagic stroke, behavioral inconsistency, and eye movement disturbance. A computational fluid dynamic study of cerebral aneurysm employs blood flow simulation wherein hemodynamic parameters indicate the rupture status of a vessel. These hemodynamic parameters actually trigger the biological factors of blood flow in the brain vessels with aneurysm. This paper offers a review of these hemodynamic parameters, and it elucidates the correlation of these parameters with cerebral aneurysm. Specifically, this review highlights the hemodynamic parameters that are related to the formation, growth, and morphological features, namely, size and shape, of cerebral aneurysm Keywords—Cerebral aneurysm, Hemodynamics, Wall shear stress, rupture risk, ansys

New, Optimized Skin Calorimeter Version for Measuring Thermal Responses of Localized Skin Areas during Physical Activity.

We present an optimized version of the skin calorimeter for measuring localized skin thermal responses during physical activity. Enhancements include a new holding system, more sensitive thermopiles, and an upgraded spiked heat sink for improved efficiency. In addition, we used a new, improved calorimetric model that takes into account all the variables that influence the measurement process. Resolution in power measurement is 1 mW. Performance tests under air currents and movement disturbances showed that the device maintains high accuracy; the deviation produced by these significant disturbances is less than 5%. Human subject tests, both at rest and during exercise, confirmed its ability to accurately measure localized skin heat flux, heat capacity, and thermal resistance (less than 5% uncertainty). These findings highlight the calorimeter's potential for applications in sports medicine and physiological studies.

Vertical “Half-and-Half” Syndrome with Ipsilateral Pseudoabducens Palsy due to Rostral Midbrain Lacunar Infarction

Vertical "half-and-half" syndrome, characterized by contralateral upward and ipsilateral downward gaze palsy, is a rare variant of vertical eye movement disturbance. Similarly, pseudoabducens palsy, manifesting as abductive palsy despite no lesion to the pons, constitutes another rare type of eye movement disturbance. Both conditions have been associated with lesions in the thalamo-mesencephalic junction. We present a rare case report detailing a patient exhibiting vertical "half-and-half" syndrome with ipsilateral pseudoabducens palsy following a left lacunar infarction of the thalamo-mesencephalic junction. Additionally, we discuss the potential underlying mechanisms contributing to this rare combination of eye movement disorders.

Objective sleep enhancement in Parkinson's disease: A sham-controlled trial of low-frequency repetitive transcranial magnetic stimulation over the right dorsolateral prefrontal cortex

IntroductionParkinson's disease (PD) is often accompanied by sleep disturbances, impacting patients' quality of life. While repetitive transcranial magnetic stimulation (rTMS) shows promise in improving self-reported sleep quality, its effects on objective sleep architecture in PD remain understudied. Sleep disturbances, including rapid eye movement (REM) and slow-wave sleep disturbances, correlate with cognitive decline and motor symptoms. This study investigated the effect of low-frequency rTMS targeting the right dorsolateral prefrontal cortex (DLPFC) modifying objective sleep architecture and explored symptom improvement mechanisms in PD patients. MethodsIn this randomized, double-blind, sham-controlled trial, 67 PD patients received 10 consecutive days of 1-Hz rTMS over the right DLPFC. Polysomnography assessed sleep microstructure, while electroencephalogram recordings evaluated power spectral density and sleep spindle activity. Clinical scales measured sleep quality, motor symptoms, and cognition at baseline, post-treatment, and 3 months post-rTMS. ResultsThe rTMS group exhibited improvements in sleep quality, motor symptoms, and cognition post-treatment, persisting at the 3-month follow-up. There was a notable increase in the REM sleep proportion post-rTMS. The rTMS group exhibited elevated low-frequency (0.5–2 Hz) slow-wave electroencephalogram spectral density during non-REM sleep. Cognitive enhancement correlated with increased lower delta power, while motor symptom progression correlated with spindle frequency and slow-wave sleep percentage changes. ConclusionLow-frequency rTMS targeting the right DLPFC holds promise for improving clinical symptoms and modulating sleep architecture in PD. These findings suggest a link between symptom improvement and sleep structure enhancement, highlighting the need for further investigation into the therapeutic potential of rTMS in PD management.

The Role of Verbal Fluency in the Cerebellar Cognitive Affective Syndrome Scale in Friedreich Ataxia

Cerebellar pathology engenders the disturbance of movement that characterizes Friedreich ataxia (FRDA), yet the impact of cerebellar pathology on cognition in FRDA remains unclear. Numerous studies have unequivocally demonstrated the role of the cerebellar pathology in disturbed cognitive, language and affective regulation, referred to as Cerebellar Cognitive Affective Syndrome (CCAS), and quantified by the CCAS-Scale (CCAS-S). The presence of dysarthria in many individuals with ataxia, particularly FRDA, may confound results on some items of the CCAS-S resulting in false-positive scores. This study explored the relationship between performance on the CCAS-S and clinical metrics of disease severity in 57 adults with FRDA. In addition, this study explored the relationship between measures of intelligibility and naturalness of speech and scores on the CCAS-S in a subgroup of 39 individuals with FRDA. We demonstrated a significant relationship between clinical metrics and performance on the CCAS-S. In addition, we confirmed the items that returned the greatest rate of failure were based on Verbal Fluency Tasks, revealing a significant relationship between these items and measures of speech. Measures of speech explained over half of the variance in the CCAS-S score suggesting the role of dysarthria in the performance on the CCAS-S is not clear. Further work is required prior to adopting the CCAS-S as a cognitive screening tool for individuals with FRDA.

The Secure Therapeutic Effects of Recently Developed Antipsychotic Drugs and Updated Neural Networks in Schizophrenia

Introduction:: Schizophrenia and schizoaffective disorder are treated in most cases with antipsychotic drugs of the second generation. These drugs block dopaminergic and serotonergic receptors, i.e., D2 and 5-HT2A receptors, and cause different adverse effects, for example, movement disturbances of the extrapyramidal system and adverse effects of vital parameters and of the heart. These drugs treat positive symptoms in schizophrenia and, to a lesser extent, negative symptoms. This review presents the development of newer antipsychotic drugs. Methods/Material:: References were taken from PubMed after using the following keywords: schizophrenia, schizoaffective disorder, antipsychotic drug, neurotransmitter and neuropeptide. Among these newer antipsychotic drugs are cariprazine, brexipiprazole and lumateperone, which exert a partial agonistic effect at D2 and 5-HT2A receptors, pimavanserin, a 5-HT2A receptor antagonist which treats negative symptoms in schizophrenia as add-on therapy, olanzapine combined with samidorphan, which reduces weight gain, and M4 or M1 receptor agonists, for example, xanomeline with an antipsychotic effect combined with trospium, an anticholinergic drug. Neural networks were updated in order to deduce the antipsychotic mechanism of action of newer antipsychotic drugs, especially xanomeline. Results:: The newer antipsychotic drugs cariprazine, brexipiprazole and lumateperone show antipsychotic, antimanic and anti-depressive effects, however, the efficacy on psychotic symptoms in long-term treatment has not yet been examined. Pimavanserin reduces negative symptoms in schizophrenia as an additional pharmacotherapy to treat this disorder. Olanzapine combined with samidorphan exerts good antipsychotic effects and reduces weight gain. The new antipsychotic drug xanomeline, the antipsychotic effect of which is quite different from the antidopaminergic effect, treats positive and negative symptoms in schizophrenia. Its mechanism of action was deduced from the neural networks presented. The long-term efficacy should still be examined. Conclusion:: This review is focused on newer antipsychotic drugs. The long-term efficacy of cariprazine, brexipiprazole and lumateperone in the treatment of schizophrenia should be examined further. Neural networks in the brain areas involved in schizophrenia should be examined and updated furthermore. Newer antipsychotic drugs ,for example, xanomeline, an M4 or M1 receptor agonist, which has been combined with trospium, an anticholinergic drug, the mechanism of action of which can be derived from the neural network suggested in this review.

Fenfluramin in der klinischen Anwendung: neue Therapieoption bei Dravet-Syndrom und Lennox-Gastaut-Syndrom

AbstractFenfluramine is an antiseizure medication for the treatment of Dravet and Lennox–Gastaut syndromes. This review summarizes the literature on the efficacy and tolerability of fenfluramine and presents recommendations for practical therapeutic management. With regular monitoring, this medication is generally well tolerated and to date has shown no cardiac side effects such as valve insufficiency or pulmonary hypertension in the clinical development program. However, children may experience a loss of appetite and should be closely monitored for weight loss, and sedation was observed in several overweight patients due to rapid dosage titration; therefore, a slower dosage increase than recommended might be needed for children and adults. Drug interactions should be considered before and during therapy, and dosage reductions are necessary when the medication is used in combination with stiripentol. Furthermore, bromide levels could increase with this medication. Contact with the patient or their relatives is important to determine the general state of health, potential movement disturbances, and seizure frequency so as to allow for timely dosage adjustments during the titration phase.

Orexin Neurons to Sublaterodorsal Tegmental Nucleus Pathway Prevents Sleep Onset REM Sleep-Like Behavior by Relieving the REM Sleep Pressure.

Proper timing of vigilance states serves fundamental brain functions. Although disturbance of sleep onset rapid eye movement (SOREM) sleep is frequently reported after orexin deficiency, their causal relationship still remains elusive. Here, we further study a specific subgroup of orexin neurons with convergent projection to the REM sleep promoting sublaterodorsal tegmental nucleus (OXSLD neurons). Intriguingly, although OXSLD and other projection-labeled orexin neurons exhibit similar activity dynamics during REM sleep, only the activation level of OXSLD neurons exhibits a significant positive correlation with the post-inter-REM sleep interval duration, revealing an essential role for the orexin-sublaterodorsal tegmental nucleus (SLD) neural pathway in relieving REM sleep pressure. Monosynaptic tracing reveals that multiple inputs may help shape this REM sleep-related dynamics of OXSLD neurons. Genetic ablation further shows that the homeostatic architecture of sleep/wakefulness cycles, especially avoidance of SOREM sleep-like transition, is dependent on this activity. A positive correlation between the SOREM sleep occurrence probability and depression states of narcoleptic patients further demonstrates the possible significance of the orexin-SLD pathway on REM sleep homeostasis.

Orbital Structure Involvement in Midface Fractures Impacting Ocular Injury at a Tertiary Hospital in Eastern Indonesia

ABSTRACT Introduction: The midface is a complex anatomical area consisting of several areas. Although various factors protect the eye from trauma, such as orbital rim, blink reflex, elasticity of ocular structures, and protective eye movements by hands and head, ocular injuries remain common in patients with midface fractures, with an incidence rate of up to 90.6%. This study, the first of its kind conducted in Indonesia, aims to evaluate the characteristics and incidence of ocular injuries in midface fractures and to examine the relationship between the treatment. Methods: This observational analytic study employed a retrospective cohort design, utilizing medical record data of midface fracture patients. The independent variables included age, sex, cause, incidence, segment and severity of ocular injury, number of orbital wall involvements, and treatment options. The dependent variable was midface fracture patients. The Mann–Whitney and Fisher’s exact tests were employed to analyze the multivariate data. Results: Individuals aged 32–37 were most commonly affected due to accidents, with the anterior ocular segment and maxilla bone frequently affected. There are no special factors that differentiate a person from experiencing an ocular injury in a midface fracture (P &gt; 0.05). Ocular injuries correlated with orbital wall injury (P = 0.008) at least one discontinuity. Impaired functions included movement and visual disturbances, diplopia, and dystopia (P = 0.134). Conclusions: No significant relationship was found between age, sex, and cause of trauma with ocular injuries in patients with midface fractures. However, a significant relationship was observed between the amount of orbital rim involvement and at least one wall discontinuity occurring in midface fracture patients.

Laser Based Short Range Multipurpose Security System

Abstract: This paper presents an IoT-based Laser Security System (IoT-LSS) designed to enhance perimeter security and intrusion detection capabilities. Traditional security systems often rely on cameras and motion sensors, which can be susceptible to false alarms and environmental limitations. The proposed IoT-LSS addresses these challenges by leveraging laser technology, IoT devices The interruption of the laser beam caused by an intruder's movement triggers an alert. IoT integrated with the laser pairs collect real-time data and transmit it to a central control unit. This control unit acts as the brain of the system, making intelligent decisions based on the incoming data stream. Control unit identifies object and differentiation between human movement and other environmental disturbances. The implementation of the IoT LSS demonstrates its effectiveness in reducing false alarms and providing reliable intrusion detection. The fusion of IoT and laser technology not only enhances security but also minimizes maintenance efforts compared to traditional systems. By harnessing the power of IoT, laser technology, the proposed Laser Security System showcases a promising solution for modern security challenges, contributing to a safer and more connected world.

Evaluation of the Acute and Subacute Toxicity of Aqueous Extract of Coriandrum sativum L. Seeds in Wistar Rats.

In traditional herbal medicine, the Coriandrum sativum (CS) seeds are widely used to prevent and/or treat several diseases. Despite this, research into studying their toxicity is very limited. This study aims at studying the acute and subacute toxicity of aqueous extract of coriander seeds (AECS) in Wistar rats. For acute toxicity, five dose levels (500, 1000, 2000, 3000, and 5000 mgkg-1bw) were tested per single oral administration. Subacute toxicity for 28 days was achieved by daily oral administration of AECS at doses of 1000, 2000, and 3000 mgkg-1bw. No deaths or signs were recorded or observed in rats in the five groups and the control group was after 14 days of acute toxicity study. The results of subacute toxicity revealed that the administration of AECS caused a significant difference in the body weight of rats at doses of 2000 and 3000mgkg-1bw, and in the development of movement disturbances, hypoactivity, drowsiness, weakness, and diarrhea, while histopathological examination showed vascular congestion and inflammation of the kidneys as well as hepatic necrosis. The haematological profile showed a significant increase in the number of red and white blood cells, haemoglobin, haematocrit, and a nonsignificant decrease is noticed in neutrophils at a dose of 3000 mgkg-1bw. AECS should be used with caution as it has caused some signs of toxicity and may affect the liver and kidneys if doses are repeated. However, further studies are needed to verify and clarify the toxic aspect of Coriandrum sativum L. seeds.

Disturbance of Trains Movement under the ERTMS Control System

The article presents a discussion leading to the identification the possible causes of disturbances in train movements under the supervision of the European Rail Traffic Management System ERTMS. As a consequence of detected events, unintentional initiation of a train braking procedure occurs despite the absence of objective reasons for such behaviour. In essence, the paper presents the ERTMS as a real-time system based on the two subsystems ETCS and GSM-R. Each of these subsystems includes a vehicle part and an infrastructure part. The article starts by identifying general considerations that may affect the lack of compatibility between vehicle and trackside infrastructure as a result of changes in versions of the specification (baseline). The following part of the article reviews the process leading to train braking is reviewed. The next part of the article refers to ETCS scenarios and parameters affecting the system response during operation. It referred to the considerations of message transmission between the ETCS ground infrastructure and the vehicle via the telecommunications network, including the GSM-R. The final section focuses on the causes and consequence of the overlap of the RBC's and GSM-R radio cells boundaries. The article concludes with a brief summary and conclusions.

Excessive excitability of inhibitory cortical circuit and disturbance of ballistic targeting movement in degenerative cerebellar ataxia

This study aimed to investigate abnormalities in inhibitory cortical excitability and motor control during ballistic-targeting movements in individuals with degenerative cerebellar ataxia (DCA). Sixteen participants took part in the study (DCA group [n = 8] and healthy group [n = 8]). The resting motor-threshold and cortical silent period (cSP) were measured in the right-hand muscle using transcranial magnetic stimulation over the left primary motor cortex. Moreover, the performance of the ballistic-targeting task with right wrist movements was measured. The Scale for the Assessment and Rating of Ataxia was used to evaluate the severity of ataxia. The results indicated that the cSP was significantly longer in participants with DCA compared to that in healthy controls. However, there was no correlation between cSP and severity of ataxia. Furthermore, cSP was linked to the ballistic-targeting task performance in healthy participants but not in participants with DCA. These findings suggest that there is excessive activity in the gamma-aminobutyric acid-mediated cortical inhibitory circuit in individuals with DCA. However, this increase in inhibitory activity not only fails to contribute to the control of ballistic-targeting movement but also shows no correlation with the severity of ataxia. These imply that increased excitability in inhibitory cortical circuits in the DCA may not contribute the motor control as much as it does in healthy older adults under limitations associated with a small sample size. The study's results contribute to our understanding of motor control abnormalities in people with DCA and provide potential evidence for further research in this area.

Progressive multifocal leukoencephalopathy in an HIV patient: A case report and literature review

Key Clinical MessageProgressive multifocal leukoencephalopathy (PML) is a rare opportunistic infection of the brain caused by reactivation of the JC virus, which can lead to a lytic infection of oligodendrocytes. We report a patient with HIV who developed PML.AbstractProgressive multifocal leukoencephalopathy (PML) is a rare opportunistic infection of the brain caused by reactivation of the John Cunningham virus (JCV), which can lead to a lytic infection of oligodendrocytes. Herein, we report the case of a patient with HIV who developed PML that presented as a progressive disturbance of consciousness and movement. The patient's clinical symptoms progressively deteriorated, and positive JC viral DNA in his cerebrospinal fluid (CSF) helped us diagnose him with PML. Magnetic resonance imaging (MRI) showed multiple asymmetric subcortical and deep white‐matter lesions. Although we administered immunoreconstructive therapy, the patient's condition gradually worsened. Therefore, we suggest that PML should be considered if such lesions are found in MRIs of HIV patients.

Asymmetrical distribution of roof microseismicity and its application to roof control of a deep longwall panel

Deep mining is widely carried out across the world. Due to large cover depth, both stress magnitude and fracture development are greatly enlarged, increasing the complexity in mining conditions. Correspondingly, a series of ground control problems emerge in deep coal mines, such as face collapsing, roof falling and support jamming. This study mainly focusses on the variation in roof activity along face length direction, which helps to strengthen roof control of a deep longwall panel. Geological radar detection reveals that the development of mining-induced fractures present an increasing trend from the maingate to tailgate side, implying the variation in roof activity along face length direction. Microseismic (MS) monitoring is moreover conducted, with which both spatial distribution and dynamic evolution of MS events in roof strata are thoroughly analyzed. Due to stronger influence provided by fault structures, the concentration of MS number mainly occurs to the tailgate section. Thus, roof microseismicity is brisker in the referred section, accounting for 63.7% of the total events. The sensitivity of MS energy to fault structures is weaker than that of MS number. Energy concentration can be observed in the whole panel width. In the maingate section, the energy proportion reaches 44.1%, indicating stronger roof microseismicity. Such asymmetrical distribution in roof microseismicity is sensitive to fault activation, fracture influence and mining disturbance. The location of fault structures, spatial variation in fracture parameters and the difference in stress rotation characteristics contribute to asymmetrical distribution in roof microseismicity on two sides of the target panel. Based on MS characteristics, a coordinative movement method is innovatively proposed for hydraulic supports, which weakens cyclic disturbance of support movement on roof strata at the face area. The method is proved to be effective by the improvement in roof stability and mining efficiency.

A retrospective study on the use of Botulinum toxin as part of first line of management in the treatment of myogenous TMD

Statement of the problem Temporomandibular disorder (TMD) represents a common group of disorders related to the impairment of the temporomandibular joints and the associated neuro-muscular system, which commonly present with features such as pain in the orofacial region, headache, joint sounds, and disturbances in jaw movements. Recently, botulinum toxin type-A (BTX-A) has increasingly been used as an adjuvant treatment for TMD. Purpose of the study This retrospective study aims to evaluate the effectiveness of BTX-A for the management of myogenous TMD and its potential to be included as a first line of treatment. Materials and methods A retrospective search was carried out through the Oral and Maxillofacial Department’s logbook from January 1, 2016, to December 31, 2020. Patients who received BTX-A for the management of myogenous TMD were identified and their hospital electronic records were accessed. Results From January 1, 2016, to December 31, 2020, 60 patients were diagnosed with myogenous TMD and treated conservatively together with intramuscular injections of BTX-A. Forty-five patients (75%) reported improvement in pain levels, of whom 10 (17%) reported complete resolution of pain. Fifteen patients (25%) reported no improvement in pain levels, of whom four (7%) reported transient improvement in pain levels lasting four weeks. A mean improvement of 50% was reported in terms of self-perceived pain levels. No adverse effects from BTX-A treatment were reported. Conclusion Although BTX-A shows great potential to be included as a first line of treatment for myogenous TMD, more high-quality research with larger sample sizes, minimal bias, and longer follow-up periods is needed.

Linear and landscape disturbances alter Mojave desert tortoise movement behavior

IntroductionAnimal movements are influenced by landscape features; disturbances to the landscape can alter movements, dispersal, and ultimately connectivity among populations. Faster or longer movements adjacent to a localized disturbance or within disturbed areas could indicate reduced habitat quality whereas slower or shorter movements and reduced movements may indicate greater availability of resources. The Mojave desert tortoise (Gopherus agassizii) is a threatened species that is challenged by anthropogenic disturbances.MethodsWe studied tortoise movements using Global Positioning System (GPS) loggers at multiple sites in the Mojave Desert of Nevada and California. Tortoises at our sites encountered localized, linear human infrastructure, including paved roads, dirt roads, and fences, as well as landscape-scale disturbances [wildfire, off highway vehicle use (OHV), livestock grazing area]. We fit two-state (moving and encamped) Hidden Markov models to GPS logger data to infer how tortoise movement behavior relates to anthropogenic and natural features.ResultsWe found that temporal covariates, individual-level random effects (intercepts), and sex best explained state transition probability in all sites. We compared relationships between tortoise movement and linear disturbances, which varied depending on site and context. Tortoises made longer movements within the OHV recreation area, near most dirt roads, and near a low-traffic paved road, indicating that tortoises avoid these habitat disturbances. Conversely, tortoises made shorter movements in areas of higher slope and near highways, suggesting that these features may restrict movement or provide resources that result in prolonged use (e.g., forage or drinking locations). Tortoises that encountered fences around utility-scale solar installations were more active and made longer movements near fences, indicative of pacing behavior.DiscussionThese results provide insight into how different disturbances alter tortoise movement behavior and modify tortoise habitat use, providing information that can be used to manage tortoise habitat.

Influence of TRPV1 on Thermal Nociception in Rats with Temporomandibular Joint Persistent Inflammation Evaluated by the Operant Orofacial Pain Assessment Device (OPAD).

Temporomandibular joint (TMJ)-associated inflammation contributes to the pain reported by patients with temporomandibular disorders (TMD). It is common for patients diagnosed with TMD to report pain in the masticatory muscles and temporomandibular joints, headache, and jaw movement disturbances. Although TMD can have different origins, including trauma and malocclusion disorder, anxiety/depression substantially impacts the development and maintenance of TMD. In general, rodent studies on orofacial pain mechanisms involve the use of tests originally developed for other body regions, which were adapted to the orofacial area. To overcome limitations and expand knowledge in orofacial pain, our group validated and characterized an operant assessment paradigm in rats with both hot and cold stimuli as well mechanical stimuli. Nevertheless, persistent inflammation of the TMJ has not been evaluated with this operant orofacial pain assessment device (OPAD). We characterized the thermal orofacial sensitivity for cold, neutral, and hot stimuli during the development of TMD using the OPAD behavior test. In addition, we evaluated the role of transient receptor potential vanilloid 1 (TRPV1) expressing nociceptors in rats with persistent TMJ inflammation. The experiments were performed in male and female rats with TMJ inflammation induced by carrageenan (CARR). Additionally, resiniferatoxin (RTX) was administered into the TMJs prior CARR to lesion TRPV1-expressing neurons to evaluate the role of TRPV1-expressing neurons. We evidenced an increase in the number of facial contacts and changes in the number of reward licks per stimulus on neutral (37°C) and cold (21°C) temperatures. However, at the hot temperature (42°C), the inflammation did not induce changes in the OPAD test. The prior administration of RTX in the TMJ prevented the allodynia and thermal hyperalgesia induced by CARR. We showed that TRPV-expressing neurons are involved in the sensitivity to carrageenan-induced pain in male and female rats evaluated in the OPAD.

Subclinical involvement of eye movements detected by video-based eye tracking in myasthenia gravis.

Ocular abnormalities in myasthenia gravis (MG) are characterized by severely limited movements and rapid saccades. Data about eye motility of MG patients whose ocular movements are apparently normal are lacking. Our study assessed the eye movement parameters in MG patients without clinical eye motility dysfunctions and investigated the effects of neostigmine administration on the eye motility in these patients. In this longitudinal study, we screened all patients diagnosed with MG referring to the Neurologic Clinic of the University of Catania between October 1, 2019, and June 30, 2021. Ten age- and sex-matched healthy controls were enrolled. Patients underwent eye movement recording using the EyeLink1000 Plus® eye tracker at baseline and after 90min from the intramuscular administration of neostigmine (0.5mg). A total of 14 MG patients with no clinical signs of ocular motor dysfunction (64.3% men, with a mean age of 50.4 ± 14.4years) were enrolled. At baseline, saccades in MG patients showed slower velocities and longer latencies compared to controls. Moreover, the fatigue test induced a reduction in saccadic velocity and an increase in latencies. After neostigmine administration, the ocular motility analysis showed shorter saccadic latencies and a significant improvement of velocities. Eye motility is impaired even in MG patients with no clinical evidence of ocular movement disturbance. Video-based eye tracking may detect subclinical involvement of eye movements in patients with MG.