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1.
Int J Dev Neurosci ; 84(6): 520-532, 2024 Oct.
Article in English | MEDLINE | ID: mdl-38858858

ABSTRACT

Hypoxia in preterm infants is a clinical condition that has been associated with cognitive and behavioral disturbances for which treatment strategies are strongly required. Melatonin administration following brain insults has been considered a promising therapeutic strategy due to its antioxidant and anti-inflammatory effects. Not surprisingly, it has been extensively studied for preventing disturbances following brain injury. This study evaluated the effects of melatonin on developmental disturbances, memory disruption, and hippocampal cell loss induced by neonatal anoxia in rats. Neonatal Wistar rats were subjected to anoxia and subsequently treated with melatonin. Later, maturation of physical characteristics, ontogeny of reflexes, learning and memory in the Morris water maze (MWM), and estimates of the number of hippocampal neurons, were evaluated. Melatonin treatment attenuated (1) female anoxia-induced delay in superior incisor eruption, (2) female anoxia-induced vibrissae placement reflexes, and (3) male and female anoxia-induced hippocampal neuronal loss. Melatonin also promoted an increase (5) in swimming speeds in the MWM. In addition, PCA analysis showed positive associations between the acoustic startle, auditory canal open, and free fall righting parameters and negative associations between the male vehicle anoxia group and the male melatonin anoxia group. Therefore, melatonin treatment attenuates both anoxia-induced developmental deficits and hippocampal neuronal loss.


Subject(s)
Animals, Newborn , Hippocampus , Maze Learning , Melatonin , Rats, Wistar , Animals , Melatonin/pharmacology , Melatonin/therapeutic use , Female , Hippocampus/drug effects , Rats , Male , Maze Learning/drug effects , Hypoxia/complications , Neurons/drug effects , Disease Models, Animal , Antioxidants/pharmacology , Antioxidants/therapeutic use
2.
Elife ; 122024 Apr 18.
Article in English | MEDLINE | ID: mdl-38634460

ABSTRACT

Mechanosensory neurons located across the body surface respond to tactile stimuli and elicit diverse behavioral responses, from relatively simple stimulus location-aimed movements to complex movement sequences. How mechanosensory neurons and their postsynaptic circuits influence such diverse behaviors remains unclear. We previously discovered that Drosophila perform a body location-prioritized grooming sequence when mechanosensory neurons at different locations on the head and body are simultaneously stimulated by dust (Hampel et al., 2017; Seeds et al., 2014). Here, we identify nearly all mechanosensory neurons on the Drosophila head that individually elicit aimed grooming of specific head locations, while collectively eliciting a whole head grooming sequence. Different tracing methods were used to reconstruct the projections of these neurons from different locations on the head to their distinct arborizations in the brain. This provides the first synaptic resolution somatotopic map of a head, and defines the parallel-projecting mechanosensory pathways that elicit head grooming.


Subject(s)
Drosophila , Neurons , Animals , Grooming/physiology , Afferent Pathways , Neurons/physiology , Brain , Drosophila melanogaster/physiology
3.
Top Companion Anim Med ; 60: 100873, 2024.
Article in English | MEDLINE | ID: mdl-38616021

ABSTRACT

The aim of this study was to compare the safety and clinical efficacy of epidural levobupivacaine combined with fentanyl or sufentanil for bitches undergoing elective cesarean-section and the impact of these anesthetic protocols on neonatal viability. The anesthetic protocol consisted of intramuscular morphine (0.2 mg/kg), followed by an intravenous bolus of propofol, in a dose sufficient to allowed the puncture of the lumbosacral space. The dogs were randomly allocated to receive 0.5 % levobupivacaine plus fentanyl (2.5 µg/kg; LF: n = 9) or sufentanil (1 µg/kg; LS; n = 11). Maternal cardiorespiratory parameters were monitored at specific time points during surgery. Intraoperative propofol supplementation was based on the presence of head and/or thoracic limb movements. Neonatal reflex responses and the Apgar score (range 0-10 points) were assessed at 5 and 60 minutes after birth. Puppy mortality rate was recorded until 24 hours after birth. Data were analyzed using two-way ANOVA, Tukey's test, Wilcoxon signed rank test, and Fisher's exact test (P < 0.05). Intraoperatively, maternal cardiorespiratory variables and propofol requirements were similar between groups, with no detection of anesthetic complications. The puppy reflex responses did not differ between groups at any time point. The medians (range) of Apgar scores were lower (P = 0.016) in the LF [5 (1-9)] at 5 minutes in comparison with LS [6 (2-9)], while no intergroup differences were recorded at 60 minutes [LF = 8 (2-10); LS = 9 (6-10]. The total mortality rate was 4.1 %. In the LS group, no puppies died, while in the LF 8 % of the puppies died in the first 24 hours after birth (P = 0.11). Epidural levobupivacaine combined with fentanyl or sufentanil provided minimal maternal and neonatal adverse effects, but neither protocol enabled the performance of a C-section in 100 % of the French and English bulldogs, without propofol supplementation.


Subject(s)
Animals, Newborn , Cesarean Section , Fentanyl , Levobupivacaine , Sufentanil , Animals , Dogs , Female , Pregnancy , Fentanyl/administration & dosage , Fentanyl/pharmacology , Levobupivacaine/administration & dosage , Cesarean Section/veterinary , Sufentanil/administration & dosage , Anesthetics, Local/administration & dosage , Anesthesia, Epidural/veterinary , Anesthetics, Intravenous/administration & dosage , Anesthetics, Intravenous/pharmacology , Analgesics, Opioid/administration & dosage
5.
Exp Physiol ; 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38441858

ABSTRACT

A given dose of hypoxia causes a greater increase in pulmonary ventilation during physical exercise than during rest, representing an exercise-induced potentiation of the acute hypoxic ventilatory response (HVR). This phenomenon occurs independently from hypoxic blood entering the contracting skeletal muscle circulation or metabolic byproducts leaving skeletal muscles, supporting the contention that neural mechanisms per se can mediate the HVR when humoral mechanisms are not at play. However, multiple neural mechanisms might be interacting intricately. First, we discuss the neural mechanisms involved in the ventilatory response to hypoxic exercise and their potential interactions. Current evidence does not support an interaction between the carotid chemoreflex and central command. In contrast, findings from some studies support synergistic interactions between the carotid chemoreflex and the muscle mechano- and metaboreflexes. Second, we propose hypotheses about potential mechanisms underlying neural interactions, including spatial and temporal summation of afferent signals into the medulla, short-term potentiation and sympathetically induced activation of the carotid chemoreceptors. Lastly, we ponder how exercise-induced potentiation of the HVR results in hyperventilation-induced hypocapnia, which influences cerebral blood flow regulation, with multifaceted potential consequences, including deleterious (increased central fatigue and impaired cognitive performance), inert (unchanged exercise) and beneficial effects (protection against excessive cerebral perfusion).

6.
Scand J Med Sci Sports ; 34(3): e14591, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38429941

ABSTRACT

The enigmatic benefits of acute limb ischemic preconditioning (IP) in enhancing muscle force and exercise performance have intrigued researchers. This study sought to unravel the underlying mechanisms, focusing on increased neural drive and the role of spinal excitability while excluding peripheral factors. Soleus Hoffmann (H)-reflex /M-wave recruitment curves and unpotentiated supramaximal responses were recorded before and after IP or a low-pressure control intervention. Subsequently, the twitch interpolation technique was applied during maximal voluntary contractions to assess conventional parameters of neural output. Following IP, there was an increase in both maximum normalized force and voluntary activation (VA) for the plantar flexor group, with negligible peripheral alterations. Greater benefits were observed in participants with lower VA levels. Despite greater H-reflex gains, soleus volitional (V)-wave and sEMG amplitudes remained unchanged. In conclusion, IP improves muscle force via enhanced neural drive to the muscles. This effect appears associated, at least in part, to reduced presynaptic inhibition and/or increased motoneuron excitability. Furthermore, the magnitude of the benefit is inversely proportional to the skeletal muscle's functional reserve, making it particularly noticeable in under-recruited muscles. These findings have implications for the strategic application of the IP procedure across diverse populations.


Subject(s)
Ischemic Preconditioning , Muscle, Skeletal , Male , Humans , Electromyography/methods , Muscle, Skeletal/physiology , Muscle Contraction/physiology , Motor Neurons/physiology , Isometric Contraction/physiology , H-Reflex/physiology , Electric Stimulation
7.
Brain Sci ; 14(2)2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38391752

ABSTRACT

Individuals with Parkinson's disease (PD) and freezing of gait (FOG) have a loss of presynaptic inhibition (PSI) during anticipatory postural adjustments (APAs) for step initiation. The mesencephalic locomotor region (MLR) has connections to the reticulospinal tract that mediates inhibitory interneurons responsible for modulating PSI and APAs. Here, we hypothesized that MLR activity during step initiation would explain the loss of PSI during APAs for step initiation in FOG (freezers). Freezers (n = 34) were assessed in the ON-medication state. We assessed the beta of blood oxygenation level-dependent signal change of areas known to initiate and pace gait (e.g., MLR) during a functional magnetic resonance imaging protocol of an APA task. In addition, we assessed the PSI of the soleus muscle during APA for step initiation, and clinical (e.g., disease duration) and behavioral (e.g., FOG severity and APA amplitude for step initiation) variables. A linear multiple regression model showed that MLR activity (R2 = 0.32, p = 0.0006) and APA amplitude (R2 = 0.13, p = 0.0097) explained together 45% of the loss of PSI during step initiation in freezers. Decreased MLR activity during a simulated APA task is related to a higher loss of PSI during APA for step initiation. Deficits in central and spinal inhibitions during APA may be related to FOG pathophysiology.

8.
J Appl Physiol (1985) ; 136(2): 385-398, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38174374

ABSTRACT

We investigated the locomotor muscle metaboreflex control of ventilation, circulation, and dyspnea in patients with chronic obstructive pulmonary disease (COPD). Ten patients [forced expiratory volume in 1 second (FEV1; means ± SD) = 43 ± 17% predicted] and nine age- and sex-matched controls underwent 1) cycling exercise followed by postexercise circulatory occlusion (PECO) to activate the metaboreflex or free circulatory flow to inactivate it, 2) cold pressor test to interpret whether any altered reflex response was specific to the metaboreflex arc, and 3) muscle biopsy to explore the metaboreflex arc afferent side. We measured airflow, dyspnea, heart rate, arterial pressure, muscle blood flow, and vascular conductance during reflexes activation. In addition, we measured fiber types, glutathione redox balance, and metaboreceptor-related mRNAs in the vastus lateralis. Metaboreflex activation increased ventilation versus free flow in patients (∼15%, P < 0.020) but not in controls (P > 0.450). In contrast, metaboreflex activation did not change dyspnea in patients (P = 1.000) but increased it in controls (∼100%, P < 0.001). Other metaboreflex-induced responses were similar between groups. Cold receptor activation increased ventilation similarly in both groups (P = 0.46). Patients had greater type II skeletal myocyte percentage (14%, P = 0.010), lower glutathione ratio (-34%, P = 0.015), and lower nerve growth factor (NGF) mRNA expression (-60%, P = 0.031) than controls. Therefore, COPD altered the locomotor muscle metaboreflex control of ventilation. It increased type II myocyte percentage and elicited redox imbalance, potentially producing more muscle metaboreceptor stimuli. Moreover, it decreased NGF expression, suggesting a downregulation of metabolically sensitive muscle afferents.NEW & NOTEWORTHY This study's integrative physiology approach provides evidence for a specific alteration in locomotor muscle metaboreflex control of ventilation in patients with COPD. Furthermore, molecular analyses of a skeletal muscle biopsy suggest that the amount of muscle metaboreceptor stimuli derived from type II skeletal myocytes and redox imbalance overcame a downregulation of metabolically sensitive muscle afferents.


Subject(s)
Nerve Growth Factor , Pulmonary Disease, Chronic Obstructive , Humans , Nerve Growth Factor/metabolism , Reflex/physiology , Muscle, Skeletal/physiology , Dyspnea , Glutathione/metabolism , Blood Pressure/physiology
9.
Audiol Neurootol ; 29(2): 81-87, 2024.
Article in English | MEDLINE | ID: mdl-37703853

ABSTRACT

BACKGROUND: The current pandemic of COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in significant morbidity and mortality primarily associated with respiratory failure. However, it has also been reported that COVID-19 can evolve into a nervous system infection. The direct and indirect mechanisms of damage associated with SARS-CoV-2 neuropathogenesis could affect our sensory functionality, including hearing and balance. SUMMARY: In order to investigate a possible association between SARS-CoV-2 viral infection and possible damage to the vestibular system, this review describes the main findings related to diagnosing and evaluating otoneurological pathologies. KEY MESSAGES: The clinical evidence shows that SARS-CoV-2 causes acute damage to the vestibular system that would not leave significant sequelae. Recovery is similar to vestibular pathologies such as vestibular neuronitis and benign paroxysmal positional vertigo. Further basic science, clinical, and translational research is needed to verify and understand the short- and long-term effects of COVID-19 on vestibular function.


Subject(s)
COVID-19 , Vestibular Neuronitis , Vestibule, Labyrinth , Humans , SARS-CoV-2 , Vestibular Neuronitis/diagnosis , Benign Paroxysmal Positional Vertigo/diagnosis
10.
Eur J Ophthalmol ; 34(1): 252-259, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37151018

ABSTRACT

PURPOSE: To determine the total alpha-synuclein (αSyn) reflex tears and its association with retinal layers thickness in Parkinson's disease (PD). METHODS: Fifty-two eyes of 26 PD subjects and 52 eyes of age-and sex-matched healthy controls were included. Total αSyn in reflex tears was quantified using a human total αSyn enzyme-linked immunosorbent assay (ELISA) kit. The retinal thickness was evaluated with spectral-domain optical coherence tomography. The Movement Disorder Society-Unified Parkinsons Disease Rating Scale (MDS-UPDRS), Non-Motor Symptoms Scale (NMSS), and Montreal Cognitive Assessment (MoCA) were used to assess motor, non-motor, and cognition. RESULTS: In PD, total αSyn levels were increased compared to control subjects [1.76pg/mL (IQR 1.74-1.80) vs 1.73pg/mL (IQR 1.70-1.77), p < 0.004]. The nerve fiber layer, ganglion cell layer, internal plexiform layer, inner nuclear layer, and outer nuclear layer were thinner in PD in comparison with controls (p < 0.05). The outer plexiform layer and retinal pigment epithelium were thicker in PD (p < 0.05). The total αSyn levels positively correlated with the central volume of the inner nuclear layer (r = 0.357, p = 0.009). CONCLUSION: Total αSyn reflex tear levels were increased in subjects with PD compared to controls. PD patients showed significant thinning of the inner retinal layers and thickening of outer retinal layers in comparison with controls. Total αSyn levels positively correlate with the central volume of the inner nuclear layer in PD. The combination of these biomarkers might have a possible role as a diagnostic tool in PD subjects.


Subject(s)
Parkinson Disease , Humans , Parkinson Disease/diagnosis , alpha-Synuclein , Nerve Fibers , Retina , Retinal Pigment Epithelium , Tomography, Optical Coherence/methods
11.
Medicina (B.Aires) ; Medicina (B.Aires);83(6): 890-899, dic. 2023. graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1558414

ABSTRACT

Resumen Introducción : La epilepsia mioclónica juvenil (EMJ) es un síndrome epiléptico de inicio en la infancia y ado lescencia con mioclonías, convulsiones tónico-clónicas generalizadas y ausencias. Los estímulos reflejos como la sensibilidad a la luz o fotosensibilidad, la apertura y cierre palpebral y la inducción por praxias producen descargas epileptiformes y crisis. Estos desencadenan tes reflejos no son todos sistemáticamente estudiados. Objetivo : Examinar los rasgos reflejos en pacientes con EMJ. Métodos : Se evaluaron en forma consecutiva 100 adolescentes y adultos con EMJ que recibían diferentes tratamientos anticrisis. Se realizó un electroencefalogra ma standard con un protocolo de estimulación luminosa intermitente (ELI) y otro para la evaluación de las pra xias a través de una actividad neurocognitiva (ANC). El análisis estadístico fue descriptivo y de correlación. Se consideró significativa una p > 0.05. Resultados : La edad actual fue de 28+/-11 (14-67). Las crisis comenzaron a los 15 años +/-3 (Rango 8-25 años). EL 58% presentaron mioclonías y convulsiones tónico clónicas generalizadas. El 50% recibían ácido valproico y el 31% continuaban con crisis. Descargas epileptiformes en reposo 20%; hiperventilación 30%; apertura y cierre palpebral 12%; respuesta fotoparoxística en la ELI 40%; ANC 23%. Mayor porcentaje de descargas y demora en la realización de la ANC en los que presentaban crisis. El ácido valproico comparado con los otros fármacos no demostró superioridad en el control de las crisis. Conclusiones : Estos hallazgos confirman la importan cia del estudio de los rasgos reflejos para el diagnóstico, seguimiento y el control terapéutico.


Abstract Introduction : Juvenile myoclonic epilepsy (JME) is an epileptic syndrome with onset in childhood and adolescence with myoclonus, absences, and generalized tonic-clonic seizures. Reflex stimuli such as sensitivity to light or photosensitivity, eyelid opening and closing, and praxis induction produce epileptiform discharges and seizures. These reflex triggers are not all system atically studied. Objective : Examine reflex features in patients with JME. Methods : One hundred adolescents and adults with JME who received different anti-seizure treatments were evaluated consecutively. A standard electroen cephalogram was performed with an intermittent light stimulation (SLI) protocol and another for the evaluation of praxias through neurocognitive activity (CNA). The statistical analysis was descriptive and of correlation with a p > 0.05. Results : Current age was 28+/-11 (14-67). The seizure began at 15 years +/-3 (Range 8-25 years). They pre sented myoclonus and generalized tonic-clonic seizures in 58%. 50% received valproic acid and 31% continued with seizures. Epileptiform discharges at rest 20%; hy perventilation 30%; eyelid opening and closing 12%; photoparoxysmal response in SLI 40%; CNA 23%. Higher percentage of discharges and delay in performing CNA in those who presented seizures. Valproic acid com pared to other drugs did not demonstrate superiority in seizure control. Conclusions : These findings confirm the importance of studying reflex traits for diagnosis, follow-up, and therapeutic control.

12.
Medicina (B Aires) ; 83(6): 890-899, 2023.
Article in Spanish | MEDLINE | ID: mdl-38117708

ABSTRACT

INTRODUCTION: Juvenile myoclonic epilepsy (JME) is an epileptic syndrome with onset in childhood and adolescence with myoclonus, absences, and generalized tonic-clonic seizures. Reflex stimuli such as sensitivity to light or photosensitivity, eyelid opening and closing, and praxis induction produce epileptiform discharges and seizures. These reflex triggers are not all systematically studied. OBJECTIVE: Examine reflex features in patients with JME. METHODS: One hundred adolescents and adults with JME who received different anti-seizure treatments were evaluated consecutively. A standard electroencephalogram was performed with an intermittent light stimulation (SLI) protocol and another for the evaluation of praxias through neurocognitive activity (CNA). The statistical analysis was descriptive and of correlation with a p > 0.05. RESULTS: Current age was 28±11 (14-67). The seizure began at 15 years ±3 (Range 8-25 years). They presented myoclonus and generalized tonic-clonic seizures in 58%. 50% received valproic acid and 31% continued with seizures. Epileptiform discharges at rest 20%; hyperventilation 30%; eyelid opening and closing 12%; photoparoxysmal response in SLI 40%; CNA 23%. Higher percentage of discharges and delay in performing CNA in those who presented seizures. Valproic acid compared to other drugs did not demonstrate superiority in seizure control. CONCLUSIONS: These findings confirm the importance of studying reflex traits for diagnosis, follow-up, and therapeutic control.


Introducción: La epilepsia mioclónica juvenil (EMJ) es un síndrome epiléptico de inicio en la infancia y adolescencia con mioclonías, convulsiones tónico-clónicas generalizadas y ausencias. Los estímulos reflejos como la sensibilidad a la luz o fotosensibilidad, la apertura y cierre palpebral y la inducción por praxias producen descargas epileptiformes y crisis. Estos desencadenantes reflejos no son todos sistemáticamente estudiados. OBJETIVO: Examinar los rasgos reflejos en pacientes con EMJ. Métodos: Se evaluaron en forma consecutiva 100 adolescentes y adultos con EMJ que recibían diferentes tratamientos anticrisis. Se realizó un electroencefalograma standard con un protocolo de estimulación luminosa intermitente (ELI) y otro para la evaluación de las praxias a través de una actividad neurocognitiva (ANC). El análisis estadístico fue descriptivo y de correlación. Se consideró significativa una p > 0.05. RESULTADOS: La edad actual fue de 28±11 (14-67). Las crisis comenzaron a los 15 años ±3 (Rango 8-25 años). EL 58% presentaron mioclonías y convulsiones tónico clónicas generalizadas. El 50% recibían ácido valproico y el 31% continuaban con crisis. Descargas epileptiformes en reposo 20%; hiperventilación 30%; apertura y cierre palpebral 12%; respuesta fotoparoxística en la ELI 40%; ANC 23%. Mayor porcentaje de descargas y demora en la realización de la ANC en los que presentaban crisis. El ácido valproico comparado con los otros fármacos no demostró superioridad en el control de las crisis. CONCLUSIONES: Estos hallazgos confirman la importancia del estudio de los rasgos reflejos para el diagnóstico, seguimiento y el control terapéutico.


Subject(s)
Epilepsies, Myoclonic , Myoclonic Epilepsy, Juvenile , Myoclonus , Adult , Adolescent , Humans , Myoclonic Epilepsy, Juvenile/diagnosis , Myoclonic Epilepsy, Juvenile/drug therapy , Valproic Acid/therapeutic use , Electroencephalography , Reflex , Seizures
13.
Front Integr Neurosci ; 17: 1234613, 2023.
Article in English | MEDLINE | ID: mdl-37711909

ABSTRACT

The comprehension of the neural elements interacting in the spinal cord affected by vestibular input will contribute to the understanding of movement execution in normal and pathological conditions. In this context, Hoffman's reflex (H-reflex) has been used to evaluate transient excitability changes on the spinal cord descending pathways. The post-activation depression (P-AD) of the H-reflex consists of evoking consecutive responses (>1 Hz) provoking an amplitude depression, which has been shown to diminish in pathological conditions (i.e., spasticity, diabetic neuropathy). Galvanic Vestibular Stimulation (GVS) is a non-invasive method that activates the vestibular afferents and has been used to study the excitability of the H-reflex applied as a conditioning pulse. To our knowledge, there are no reports evaluating the P-AD during and after GVS. Our primary aim was to determine if GVS alters the P-AD evoked by stimulating the tibial nerve at 0.1, 1, 5, and 10 Hz, recording in the gastrocnemius and soleus muscles. Direct current stimulation of 2.0 ± 0.6 mA with the cathode ipsilateral (Ipsi) or contralateral (Contra) to the H-reflex electrode montage was applied bilaterally over the mastoid process in 19 healthy subjects. The P-AD's immediate post-GVS response (P Ipsi, P Contra) was also analyzed. Secondarily, we analyzed the excitability of the H-reflex during GVS. Responses evoked at 0.1 Hz with GVS, post-GVS, and a Control (no GVS) condition were used for comparisons. Our results show that P-AD persisted in all subjects despite increased excitability induced by GVS: statistical significance was found when comparing P-AD at 1, 5, and 10 Hz with the corresponding condition (Control, Ipsi, P Ipsi, Contra, P Contra) at 0.1 Hz (p < 0.001). Additionally, the increase in excitability produced by GVS was quantified for the first H-reflex of each P-AD stimulation frequency. The percentage change for all GVS conditions surpassed the Control by at least 20%, being statistically significant for Contra compared to Control (p < 0.01). In summary, although GVS increases the excitability of the vestibulospinal pathway at a premotor level, the neural inhibitory mechanism present in P-AD remains unaltered in healthy subjects.

14.
J Pediatr ; 263: 113652, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37527702
15.
Front Endocrinol (Lausanne) ; 14: 1206552, 2023.
Article in English | MEDLINE | ID: mdl-37476495

ABSTRACT

Diabetes Mellitus is a public health problem associated with complications such as neuropathy; however, it has been proposed that these may begin to develop during prediabetes and may also be present in persons with obesity. Diabetic peripheral neuropathy is the presence of signs and/or symptoms of peripheral nerve dysfunction in people living with diabetes, which increases the risk of developing complications and has a deleterious impact on quality of life. As part of the therapeutic protocol for diabetes, screening tests to identify peripheral neuropathy are suggested, however, there are no recommendations for people with prediabetes and obesity without symptoms such as pain, numbness, or paresthesias. Moreover, clinical screening tests that are usually used to recognize this alteration, such as tendon reflex, temperature sensation, and pressure and vibration perception, might be subjective as they depend on the evaluator's experience thus the incorrect application of these tests may not recognize the damage to small or large-nerve fibers. Recent evidence suggests that an objective study such as the impairment of the rate-dependent depression of the H-reflex could be used as a biomarker of spinal disinhibition and hence may provide more information on sensorimotor integration.


Subject(s)
Diabetic Neuropathies , Prediabetic State , Humans , Prediabetic State/complications , Prediabetic State/diagnosis , H-Reflex/physiology , Quality of Life , Diabetic Neuropathies/diagnosis , Diabetic Neuropathies/etiology , Obesity/complications
16.
J. coloproctol. (Rio J., Impr.) ; 43(3): 159-165, July-sept. 2023. tab, ilus
Article in English | LILACS | ID: biblio-1521149

ABSTRACT

Introduction: Distension of the rectum wall and subsequent momentary relaxation of the internal anal sphincter (IAS) trigger a reflex called the rectoanal inhibitory reflex (RAIR). This same rectal distension causes a reflex contraction of the external anal sphincter (EAS), responsible for conscious continence called rectoanal excitatory reflex (RAER). This set of reflexes are named sampling reflex. Objectives: The sampling reflex is necessary to initiate defecation or flatulence. The objective of this study is to evaluate the sampling reflex and its practical applicability as a manometric marker of the main defecation disorders. Methodology: This review followed the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) items. The development method consisted of searching for articles in the research platforms BVS, PubMed, Cochrane Library, SciELO and ScienceDirect and for the selection of articles the Rayyan Platform was used. The articles resulting from the search strategies were added to the platform and five collaborators were invited for the blind selection. Finally, 6 articles were included in the final review. Results: An intact sampling reflex allows the individual to facilitate discrimination between flatus and stool and to choose whether to discharge or retain rectal contents. On the other hand, an impaired sampling reflex can predispose an individual to incontinence. Therefore, it was observed that patients with defecation disorders had an impaired sampling reflex, since it was found that constipated patients have incomplete opening of the IAS, lower amplitude of RAIR and increase of RAER. Most incontinent patients present a failure in the recruitment of the EAS, a decrease in the RAER and an increase in the RAIR, in duration and amplitude. (AU)


Subject(s)
Humans , Anal Canal/physiopathology , Fecal Incontinence/diagnosis , Reflex , Constipation , Manometry
17.
Braz J Otorhinolaryngol ; 89(4): 101279, 2023.
Article in English | MEDLINE | ID: mdl-37354884

ABSTRACT

OBJECTIVE: To analyze, by means of a systematic review and meta-analysis, the proportion of patients with Meniere's disease who have altered caloric test and vHIT, as well as to determine the prevalence of altered caloric test and normal vHIT dissociation in the diagnosis of Meniere's disease. METHODS: The literature search had no restriction regarding the period of publication on the following indexed data platforms: PubMed, PubMed PMC, BVS-Bireme, Web of Science, Embase and Cochrane Library. Articles that evaluated patients with Meniere's disease who underwent caloric test and vHIT were included. Two researchers independently conducted the analysis of the articles, promoting the selection and capture of data, following the recommendations of the PRISMA method, and complying with the criteria for articles inclusion and exclusion defined in the research protocol. In case of disagreement during the selection process, a third researcher was included for analysis. RESULTS: From a total of 427 initial studies, the researchers selected 12 articles, published between 2014 and 2021, with a total of 708 patients evaluated, with a mean age of 52.72 years old. The prevalence of patients with Meniere's disease with altered caloric reflex test was 64% (95% CI 57%‒71%), while the prevalence of altered vHIT was only 28% (95% CI 16%-40%). The prevalence of the altered caloric test + normal vHIT dissociation was 47% (95% CI 37%-57%). CONCLUSION: The video head impulse test and the caloric test are valuable tools for vestibular assessment. The dissociation of findings between these two tests in patients with Meniere's disease was more prevalent in this meta-analysis and may be a result of the tonotopy of specialized hair cells in the ampullary crest. The prevalence of altered caloric test was 64% and anormal vHIT was 28%. The dissociation caloric asymmetry and normal vHIT was observed in 47% of the patients.


Subject(s)
Meniere Disease , Humans , Middle Aged , Meniere Disease/diagnosis , Head Impulse Test/methods , Caloric Tests/methods , Reflex, Vestibulo-Ocular , Hair Cells, Auditory
18.
Braz. j. otorhinolaryngol. (Impr.) ; Braz. j. otorhinolaryngol. (Impr.);89(3): 447-455, May-June 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1447702

ABSTRACT

Abstract Objective Pediatric orbital blowout fractures can include pathologies that seem mild but require urgent release; serious sequelae can occur with standby surgery or conservative treatment. We sought to validate an algorithm for the treatment of pediatric orbital blowout fractures. Methods This retrospective cohort study included 61 pediatric patients, aged 18 years or younger, treated for pure orbital blowout fractures according to the algorithm from April 1, 2000, to August 31, 2020, at the Japanese Red Cross Asahikawa Hospital. Results There were 52 males (85%). Median age was 14 years (range, 5-18 years). There were 9 patients categorized as needing urgent release, 16 as needing repair, and 36 as needing conservative treatment. Mean follow-up ocular movement was 98.0 (95% Confidence Interval [95% CI], 96.8-99.2). Postoperative diplopia was not observed in 96% (79.6%-99.9%) of patients, better than in previous studies. A higher proportion of patients aged 0-12 years needed urgent repair than those aged 13-18 years (Odds Ratio [OR] = 14.2; 95% CI 1.6-683.4; p= 0.0046). There were no differences in Hess area ratio by age group. Conclusion Clinical results with the algorithm were satisfactory. The algorithm is suitable for treatment of pediatric orbital blowout fractures. Level of evidence 4.

19.
Neuroimmunomodulation ; 30(1): 102-112, 2023.
Article in English | MEDLINE | ID: mdl-37232031

ABSTRACT

Bioelectronic medicine is a novel field in modern medicine based on the specific neuronal stimulation to control organ function, cardiovascular, and immune homeostasis. However, most studies addressing neuromodulation of the immune system have been conducted on anesthetized animals, which can affect the nervous system and neuromodulation. Here, we review recent studies involving conscious experimental rodents (rats and mice) to better understand the functional organization of neural control of immune homeostasis. We highlight typical experimental models of cardiovascular regulation, such as electrical activation of the aortic depressor nerve or the carotid sinus nerve, bilateral carotid occlusion, the Bezold-Jarisch reflex, and intravenous administration of the bacterial endotoxin lipopolysaccharide. These models have been used to investigate the relationship between neuromodulation of the cardiovascular and immune systems in conscious rodents (rats and mice). These studies provide critical information about the neuromodulation of the immune system, particularly the role of the autonomic nervous system, i.e., the sympathetic and parasympathetic branches acting both centrally (hypothalamus, nucleus ambiguus, nucleus tractus solitarius, caudal ventrolateral medulla, and rostral ventrolateral medulla), and peripherally (particularly spleen and adrenal medulla). Overall, the studies in conscious experimental models have certainly highlighted to the reader how the methodological approaches used to investigate cardiovascular reflexes in conscious rodents (rats and mice) can also be valuable for investigating the neural mechanisms involved in inflammatory responses. The reviewed studies have clinical implications for future therapeutic approaches of bioelectronic modulation of the nervous system to control organ function and physiological homeostasis in conscious physiology.


Subject(s)
Inflammation , Solitary Nucleus , Rats , Mice , Animals , Solitary Nucleus/physiology , Neurons , Autonomic Nervous System , Hypothalamus , Sympathetic Nervous System , Heart Rate/physiology , Blood Pressure/physiology
20.
J Pediatr ; 258: 113412, 2023 07.
Article in English | MEDLINE | ID: mdl-37023944

Subject(s)
Amblyopia , Strabismus , Humans , Cornea , Reflex
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