RESUMO
In the brain, microRNAs (miRNAs) are believed to play a role in orchestrating synaptic plasticity at a higher level by acting as an additional mechanism of translational regulation, alongside the mRNA/polysome system. Despite extensive research, our understanding of the specific contribution of individual miRNA to the function of dopaminergic neurons (DAn) remains limited. By performing a dopaminergic-specific miRNA screening, we have identified miR-218 as a critical regulator of DAn activity in male and female mice. We have found that miR-218 is specifically expressed in mesencephalic DAn and is able to promote dopaminergic differentiation of embryonic stem cells and functional maturation of transdifferentiated induced DA neurons. Midbrain-specific deletion of both genes encoding for miR-218 (referred to as miR-218-1 and mir218-2) affects the expression of a cluster of synaptic-related mRNAs and alters the intrinsic excitability of DAn, as it increases instantaneous frequencies of evoked action potentials, reduces rheobase current, affects the ionic current underlying the action potential after hyperpolarization phase, and reduces dopamine efflux in response to a single electrical stimulus. Our findings provide a comprehensive understanding of the involvement of miR-218 in the dopaminergic system and highlight its role as a modulator of dopaminergic transmission.SIGNIFICANCE STATEMENT In the past decade, several miRNAs have emerged as potential regulators of synapse activity through the modulation of specific gene expression. Among these, we have identified a dopaminergic-specific miRNA, miR-218, which is able to promote dopaminergic differentiation and regulates the translation of an entire cluster of synapse related mRNAs. Deletion of miR-218 has notable effects on dopamine release and alters the intrinsic excitability of dopaminergic neurons, indicating a direct control of dopaminergic activity by miR-218.
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Dopamina , MicroRNAs , Camundongos , Masculino , Feminino , Animais , Dopamina/metabolismo , Diferenciação Celular , Neurônios Dopaminérgicos/fisiologia , MicroRNAs/genética , MicroRNAs/metabolismo , Neurotransmissores/metabolismoRESUMO
Hearing loss in the elderly is a very common disease: it is estimated to affect up to a third of the population aged 65 years or more, and 50% of people over 75 years old. There is a growing amount of data concerning the association between hearing loss and cognitive decline. Various possible mechanisms at the basis of this association have been proposed, such as the "common cause hypothesis," the "cascade hypothesis," and the "cognitive load hypothesis."Critically reviewing the data is essential to highlight the features of the relationship between hearing loss and cognitive decline. Most of the hearing tests available should take into account that dementia or even just mild cognitive impairment (MCI) may lead to poor performance during examination. On the other hand, clinicians should also remember that tests used to assess cognitive function require an adequate hearing capacity.In this article we propose to analyze current diagnostic tests, treatment options, auditory processing, and rehabilitation strategies for hearing loss in the elderly in order to facilitate the management of this handicap in this fragile population.
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Disfunção Cognitiva , Perda Auditiva , Percepção da Fala , Idoso , Humanos , Envelhecimento , Perda Auditiva/complicações , Perda Auditiva/psicologia , Percepção Auditiva , Disfunção Cognitiva/diagnóstico , EncéfaloRESUMO
Child maltreatment disrupts trajectories of brain development, but the underlying pathways are unclear. Stressful stimuli in early life interfere with maturation of local inhibitory circuitry and deposition of perineuronal nets (PNNs), specialized extracellular matrix structures involved in the closure of critical periods of development. Alterations in cortical PNN and parvalbumin (PV) following early-life stress (ELS) have been detected in human and animal studies. Aberrations in the anterior cingulate cortex (ACC) are the most consistent neuroimaging findings in maltreated people, but the molecular mechanisms linking ELS with ACC dysfunctions are unknown. Here, we employed a mouse model of early social threat to test whether ELS experienced in a sensitive period for ACC maturation could induce long-term aberrations of PNN and PV development in the ACC, with consequences on plasticity and ACC-dependent behavior. We found that ELS increased PNN but not PV expression in the ACC of young adult mice. This was associated with reduced frequency of inhibitory postsynaptic currents and long-term potentiation impairments and expression of intense object phobia. Our findings provide information on the long-term effects of ELS on ACC functionality and PNN formation and present evidence for a novel neurobiological pathway underlying the impact of early adversity on the brain.
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Experiências Adversas da Infância , Giro do Cíngulo , Humanos , Criança , Camundongos , Animais , Giro do Cíngulo/metabolismo , Parvalbuminas/metabolismo , Matriz Extracelular/metabolismoRESUMO
Misfolding and aggregation of α-synuclein are specific features of Parkinson's disease and other neurodegenerative diseases defined as synucleinopathies. Parkinson's disease progression has been correlated with the formation and extracellular release of α-synuclein aggregates, as well as with their spread from neuron to neuron. Therapeutic interventions in the initial stages of Parkinson's disease require a clear understanding of the mechanisms by which α-synuclein disrupts the physiological synaptic and plastic activity of the basal ganglia. For this reason, we identified two early time points to clarify how the intrastriatal injection of α-synuclein-preformed fibrils in rodents via retrograde transmission induces time-dependent electrophysiological and behavioural alterations. We found that intrastriatal α-synuclein-preformed fibrils perturb the firing rate of dopaminergic neurons in the substantia nigra pars compacta, while the discharge of putative GABAergic cells of the substantia nigra pars reticulata is unchanged. The α-synuclein-induced dysregulation of nigrostriatal function also impairs, in a time-dependent manner, the two main forms of striatal synaptic plasticity, long-term potentiation and long-term depression. We also observed an increased glutamatergic transmission measured as an augmented frequency of spontaneous excitatory synaptic currents. These changes in neuronal function in the substantia nigra pars compacta and striatum were observed before overt neuronal death occurred. In an additional set of experiments, we were able to rescue α-synuclein-induced alterations of motor function, striatal synaptic plasticity and increased spontaneous excitatory synaptic currents by subchronic treatment with l-DOPA, a precursor of dopamine widely used in the therapy of Parkinson's disease, clearly demonstrating that a dysfunctional dopamine system plays a critical role in the early phases of the disease.
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Plasticidade Neuronal/fisiologia , Doença de Parkinson/fisiopatologia , Substância Negra/fisiopatologia , Transmissão Sináptica/fisiologia , alfa-Sinucleína/toxicidade , Animais , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Masculino , Doença de Parkinson/metabolismo , Ratos , Ratos Wistar , Substância Negra/metabolismo , alfa-Sinucleína/metabolismoRESUMO
BACKGROUND: While it is well established that frail older people have a higher risk of negative health outcomes, the prevalence of frailty and its associated factors in Italian older institutionalized population has never been investigated. AIMS: The aims of this study were to assess the prevalence of frailty and to identify its associated factors in an Italian residential care home population. METHODS: An observational cross-sectional study was designed to evaluate older people aged 70 or over of an Italian residential care home. A multidimensional assessment examining functional, geriatric, ophthalmic, and audiological domains was carried out to identify factors associated with frailty. Physical frailty was evaluated using Fried's criteria. RESULTS: Data analysis uncovered a 51.1% prevalence of pre-frailty and a 40.4% prevalence of frailty in the 94 eligible participants (64 females) whose data were complete. The multivariable analysis showed that a low education level (OR = 5.12, 95% CI 1.22-21.49), a low physical quality of life score (OR = 13.25, 95% CI 3.51-50.08), a low mental quality of life score (OR = 9.22, 95% CI 2.38-35.69), visual impairment (OR = 7.65, 95% CI 1.77-33.14), and hearing impairment (OR = 4.62, 95% CI 1.03-20.66) were independently associated with frailty. CONCLUSIONS: Frailty was found to be highly prevalent in the residential care home studied. Since frailty is a reversible condition, identifying the modifiable factors associated to it should be viewed as an important step in planning and implementing targeted, early prevention strategies.
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Fragilidade , Idoso , Estudos Transversais , Feminino , Idoso Fragilizado , Fragilidade/epidemiologia , Avaliação Geriátrica/métodos , Humanos , Prevalência , Qualidade de VidaRESUMO
PURPOSE: To describe our institutional experience in cochlear implantation after vestibular schwannoma (VS) resection, and compare the audiological outcomes between sporadic and neurofibromatosis type 2 (NF2) VS sub-cohorts of patients, and in relation to preoperative contralateral hearing. METHODS: Seventeen patients (8 sporadic and 9 NF2-associated VSs) who had undergone VS resection and cochlear implant (CI) were analyzed retrospectively. Audiological outcomes at 24 months were correlated with preoperative clinical variables. The results according to VS type (sporadic vs. NF2-associated) and contralateral hearing (impaired vs. normal) were compared. RESULTS: Fourteen CIs were actively used by the patients (77.8%). Twenty-four months after CI activation, the median postoperative PTA (pure tone average) was 45.6 dB nHL and a measurable WRS (Word Recognition Score) was achieved by 44.4% of patients (median WRS = 40%). The median postoperative PTA in the implanted ear resulted better in the group with an impaired contralateral hearing (36.3 dB nHL vs. 78.8 dB nHL, p = 0.019). Good preoperative contralateral hearing status (A-B classes of AAO-HNS) was a negative prognostic factor for CI performance on open-set discrimination (OR = 28.0, 95% CI 2.07-379.25, p = 0.012). CONCLUSIONS: CI is a viable rehabilitative option for patients with sporadic or NF2-associated VS. A good contralateral hearing adversely affects CI outcome and should be taken into consideration for patients' selection and rehabilitation programs.
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Implante Coclear , Implantes Cocleares , Neuroma Acústico , Implante Coclear/métodos , Perda Auditiva/cirurgia , Humanos , Neurofibromatose 2/cirurgia , Neuroma Acústico/cirurgia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
The conjugation of drugs with nanoparticles represents an innovative approach for controlled and targeted administration of therapeutic agents. Nanoparticle-based systems have been tested for the inner ear therapy, increasing the drug diffusion and being detected in all parts of the cochlea when locally applied near the round window. In this study, glycerol monooleate liquid crystalline NanoParticles were conjugated with Dexamethasone (NPD), a hydrophobic drug already used for inner ear treatments but defective in solubility and bioavailability. NPD has been tested in vitro in the cell line OC-k3, a model of sensory cells of the inner ear, and the therapeutic efficacy has been evaluated against cisplatin, a chemotherapeutic compound known to induce ototoxicity. After comparing the physical chemical characteristics of NPD to the equivalent naïve nanoparticles, an initial investigation was carried out into the nanoparticle's uptake in OC-k3 cells, which takes place within a few hours of treatment without causing toxic damage up to a concentration of 50 µg/mL. The NPD delivered the dexamethasone inside the cells at a significantly increased rate compared to the equivalent free drug administration, increasing the half-life of the therapeutic compound within the cell. Concerning the co-treatment with cisplatin, the NPD significantly lowered the cisplatin cytotoxicity after 48 h of administration, preventing cell apoptosis. To confirm this result, also cell morphology, cell cycle and glucocorticoids receptor expression were investigated. In conclusion, the NPD system has thus preliminarily shown the potential to improve the therapeutic efficacy of treatments delivered in the inner ear and prevent drug-induced ototoxicity.
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Cristais Líquidos , Nanopartículas , Ototoxicidade , Humanos , Cisplatino/toxicidade , Nanopartículas/química , Dexametasona/farmacologiaRESUMO
The biocompatibility and the antioxidant activity of barium titanate (BaTiO3) and lithium niobate (LiNbO3) were investigated on a neuronal cell line, the PC12, to explore the possibility of using piezoelectric nanoparticles in the treatment of inner ear diseases, avoiding damage to neurons, the most delicate and sensitive human cells. The cytocompatibility of the compounds was verified by analysing cell viability, cell morphology, apoptotic markers, oxidative stress and neurite outgrowth. The results showed that BaTiO3 and LiNbO3 nanoparticles do not affect the viability, morphological features, cytochrome c distribution and production of reactive oxygen species (ROS) by PC12 cells, and stimulate neurite branching. These data suggest the biocompatibility of BaTiO3 and LiNbO3 nanoparticles, and that they could be suitable candidates to improve the efficiency of new implantable hearing devices without damaging the neuronal cells.
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Antioxidantes/farmacologia , Compostos de Bário/farmacologia , Materiais Biocompatíveis/farmacologia , Nanopartículas/química , Neurônios/efeitos dos fármacos , Nióbio/farmacologia , Óxidos/farmacologia , Titânio/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular , Citocromos c/metabolismo , Crescimento Neuronal/efeitos dos fármacos , Células PC12 , Ratos , Espécies Reativas de Oxigênio/metabolismoRESUMO
BACKGROUND/OBJECTIVE: The aim of this study was to assess the impact of sinonasal morbidity on quality of life (QoL) in antineutrophil cytoplasmic antibody-associated vasculitis (AAV). METHODS: This cross-sectional case-control study enrolled 71 patients-44 AAV cases with (ear, nose, and throat [ENT]-AAV) or without ENT involvement (non-ENT-AAV) undergoing multidisciplinary evaluations and 27 chronic rhinosinusitis (CRS) cases. Three validated QoL questionnaires (Sino-Nasal Outcomes Test-22 [SNOT-22], Nasal Obstruction Symptom Evaluation [NOSE], and Short-Form 36) were administered, and the 3 groups were compared. RESULTS: The ENT-AAV patients were significantly younger (p = 0.01), with less antineutrophil cytoplasmic antibody positivity frequency (p = 0.035) and lower renal involvement (p = 0.003) than the non-ENT-AAV patients.The SNOT-22 questionnaire demonstrated significantly greater sinonasal morbidity in ENT-AAV patients compared with CRS patients (p < 0.001). The NOSE score of ENT-AAV patients was comparable to those of CRS patients, but higher than that of non-ENT-AAV patients (p < 0.001). The SNOT-22 and NOSE scores positively correlated with disease activity (p = 0.037; p = 0.004, respectively). Short-Form 36 domain-by-domain analysis revealed a significantly poorer QoL in ENT-AAV patients, especially with physical functioning being progressively impaired in CRS, non-ENT-AAV, and ENT-AAV patients (p < 0.001). No significant differences in QoL came to light when AAV patients were stratified according to current systemic o local treatments. CONCLUSIONS: The QoL in AAV patients is significantly reduced, especially in the presence of ENT involvement. The AAV-related nasal morbidity is consistent and comparable to that reported by CRS patients. It significantly affects patients' QoL and in particular social functioning, leading to limitation in daily/work activities. Organ-focused questionnaires and multidisciplinary management are warranted to pursue a treat-to-target approach in these patients.
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Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Sinusite , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/diagnóstico , Estudos de Casos e Controles , Doença Crônica , Estudos Transversais , Humanos , Qualidade de VidaRESUMO
INTRODUCTION: Non-syndromic hereditary hearing loss is characterized by extreme genetic heterogeneity. So far, more than 100 pathogenic or likely pathogenic variants in TMC1 gene have been reported in patients with autosomal recessive hearing loss (HL) DFNB7/11. The prevailing auditory phenotype of individuals with DFNB7/11 is congenital, profound, bilateral HL, but the functional outcome after cochlear implantation (CI) described in the literature is variable. The objective of this work is to evaluate the auditory outcome after CI in pediatric patients with DFNB7/11, born to non-consanguineous parents. METHODS: A retrospective analysis of genetic and audiological data of DFNB7/11 patients followed up in a single Italian otolaryngology clinic was performed. Cases with biallelic pathogenic variants in TMC1 were selected from the cohort of children with non-syndromic hearing loss who had undergone CI and had been molecularly characterized by multigene panel testing. All patients underwent extensive audiological assessment, and the auditory outcome after CI was evaluated. RESULTS: DFNB7/11 was diagnosed in a total of 3 patients from 2 non-consanguineous families; a novel disease-causing variant in TMC1 was detected [c.962G>A p.(Trp321*)]. All the affected children showed the typical DFNB7/11 phenotype characterized by prelingual, severe-to-profound HL. The patients showed an excellent functional outcome after CI; speech perception, nonverbal cognition, and speech performance were comparable to those of patients with DFNB1 deafness. DISCUSSION/CONCLUSION: Our results do not support the variable auditory outcome reported in the literature, which may be affected by several social and environmental factors and by the genetic background.
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Implante Coclear , Perda Auditiva Neurossensorial/cirurgia , Proteínas de Membrana/genética , Criança , Pré-Escolar , Feminino , Perda Auditiva Neurossensorial/genética , Humanos , Fenótipo , Estudos Retrospectivos , Resultado do TratamentoRESUMO
During COVID-19 pandemic, protective measures such as social distancing and face masks posed a challenge in daily communication, in this context the elderly are one of the most at risk categories as widely exposed to hearing loss. This article focuses on how the COVID-19 pandemic affected verbal communication, especially on those people that even in normal conditions present an increased difficulty in speech perception. Special attention has been paid to hearing aids and cochlear implant users, these devices indeed can be affected by a speech intelligibility reduction and could be uncomfortable if used together with face masks. Possible alternatives and solutions will be proposed to reduce the negative impacts of face coverings on communication, to enhance speech intelligibility and to manage wearability of hearing rehabilitation devices.
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COVID-19 , Implantes Cocleares , Percepção da Fala , Idoso , Humanos , Pandemias , Distanciamento Físico , SARS-CoV-2RESUMO
BACKGROUND: Retropharyngeal and parapharyngeal abscesses (RPAs, PPAs) usually affect young children. Surgical drainage and/or antibiotic therapy are treatment of choice, but no specific guidelines exist. In order to reduce the risk of severe complications, appropriate diagnosis and therapy are necessary. The aims of the study were to review diagnosis and management of children with RPAs/PPAs and to compare surgical versus medical approach. METHODS: This is a multicenter retrospective study including all patients younger than 15 years admitted at 4 Italian pediatric hospitals of Florence, Padua, Rome, and Treviso, with International Classification of Diseases, Ninth Revision discharge diagnosis code of RPAs and PPAs, from January 1, 2008, to December 31, 2016. RESULTS: One hundred fifty-three children were included. The median age was 4.4 years, with overall male predominance. Heterogeneous signs and symptoms (fever, neck cervical, lymphadenopathy, pain, and stiff neck most frequently) and a large mixture of bacteria from pus cultures were detected. Computer tomography (66.7%) and magnetic resonance imaging (27.5%) were performed to confirm the presence of abscess. Fifty-one percent of abscesses were greater than 3 cm. Eighty-seven patients (56.9%) underwent surgery, and 66 (43.1%) were treated with antibiotics alone (mostly ceftriaxone, metronidazole, amikacin, and clindamycin) with median days of therapy of 26.5 days and length of therapy of 16.0 days of median. Median length of stay was 11 days. None had severe complications. Multivariate analysis indicated as independent predictive factors of surgery abscess of 3 cm or greater, high white blood cell count, and-most of all-the hospital of admission. CONCLUSIONS: Deep neck abscesses mostly affect patients in early childhood, with a combination of nonspecific signs and symptoms, and it still emerges as a heterogeneous approach in diagnosis and management of these infections. Thus, common shared protocols represent an essential tool in order to standardize care and improve patients' outcomes.
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Drenagem , Abscesso Retrofaríngeo , Antibacterianos/uso terapêutico , Pré-Escolar , Clindamicina , Humanos , Masculino , Pescoço , Abscesso Retrofaríngeo/diagnóstico , Abscesso Retrofaríngeo/epidemiologia , Abscesso Retrofaríngeo/terapia , Estudos RetrospectivosRESUMO
PURPOSE: To reduce intensive care unit overcrowding and optimize resources, elderly patients affected by suspected infection with declining clinical conditions could be managed in internal medicine departments with stepdown beds. However, commonly used prognostic scores, as Sequential Organ Failure Assessment (SOFA) or quick SOFA (qSOFA) have never been studied in this specific setting. The aim of this study was to evaluate the role and the accuracy of SOFA and qSOFA as prognostic scores in a population of elderly patients with suspected infection admitted to stepdown beds of two internal medicine departments. METHODS: Elderly patients admitted from the emergency department in the stepdown beds of two different internal medicine departments for suspected infection were assessed with SOFA and qSOFA scores at the admission. All patients were treated according to current guidelines. Age, sex, comorbidities, Charlson comorbidity index, SOFA and qSOFA were assessed. In-hospital death and length of hospital admission were also recorded. RESULTS: 390 subjects were enrolled. In-hospital death occurred in 144 (36.9%) patients; we observed that both SOFA (HR 1.189; 95% CI 1.128-1.253; p < 0.0001) and qSOFA (HR 1.803; 95% CI 1.503-2.164; p < 0.0001) scores were independently associated with an increased risk of in-hospital death. However, the accuracy of both SOFA (AUC: 0.686; 95% CI 0.637-0.732; p < 0.0001) and qSOFA (AUC: 0.680; 95% CI 0.641-0.735; p < 0.0001) in predicting in-hospital death was low in this population. CONCLUSION: Elderly patients admitted to stepdown beds for suspected infection experience a high rate of in-hospital death; both SOFA and qSOFA scores can be useful to identify a group of patients who can benefit from admission to an intermediate care environment, however their accuracy is low.
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Mortalidade Hospitalar , Unidades de Terapia Intensiva/estatística & dados numéricos , Escores de Disfunção Orgânica , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Itália , MasculinoRESUMO
INTRODUCTION: In the ENT community, auditory deprivation is frequently considered as a negative prognostic factor for a good hearing outcome of cochlear implantation (CI), even if a growing literature suggests that this is not completely true. The purpose of this study is to evaluate the results of CI in patients with hearing deprivation, to compare them to results from non-deprived patients and then estimate how time of deprivation impacts on CI outcome and how a bilateral deprivation can affect the outcome compared to a unilateral deprivation. METHODS: Seventy-eight adults with severe to profound post-verbal hearing loss, with and without auditory deprivation history, received CI; audiological results obtained at 3-6-12-24 months follow up post CI were analyzed. RESULTS: No differences were founded between patients with unilateral deprivation and patients with no deprivation. Patients with bilateral deprivation seem to have a worse hearing outcome compared to that of those patients with unilateral deprivation or no deprivation at all. Long time deprivation (>15 years) seems to have a negative influence on the hearing outcome but results with CI remain excellent. CONCLUSIONS: Auditory deprivation should not be considered a contraindication to CI. The duration of auditory deprivation in the implanted ear seems to be a negative prognostic factor only for ears deprived from more of 15 years.
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Implante Coclear/efeitos adversos , Contraindicações de Procedimentos , Perda Auditiva/etiologia , Complicações Pós-Operatórias/etiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de TempoRESUMO
Despite the importance of somatodendritic dopamine (DA) release in the Substantia Nigra pars compacta (SNc), its mechanism remains poorly understood. Using a novel approach combining fast-scan controlled-adsorption voltammetry (FSCAV) and single-unit electrophysiology, we have investigated the mechanism of somatodendritic release by directly correlating basal (non-stimulated) extracellular DA concentration ([DA]out ), with pharmacologically-induced changes of firing of nigral dopaminergic neurons in rat brain slices. FSCAV measurements indicated that basal [DA]out in the SNc was 40.7 ± 2.0 nM (at 34 ± 0.5°C), which was enhanced by amphetamine, cocaine, and L-DOPA, and reduced by VMAT2 inhibitor, Ro4-1284. Complete inhibition of firing by TTX decreased basal [DA]out , but this reduction was smaller than the effect of D2 receptor agonist, quinpirole. Despite similar effects on neuronal firing, the larger decrease in [DA]out evoked by quinpirole was attributed to cell membrane hyperpolarization and greater reduction in cytosolic free Ca2+ ([Ca2+ ]in ). Decreasing extracellular Ca2+ also reduced basal [DA]out , despite increasing firing frequency. Furthermore, inhibiting L-type Ca2+ channels decreased basal [DA]out , although specific Cav 1.3 channel inhibition did not affect firing rate. Inhibition of sarcoplasmic/endoplasmic reticulum Ca2+ -ATPase (SERCA) also decreased [DA]out , demonstrating the importance of intracellular Ca2+ stores for somatodendritic release. Finally, in vivo FSCAV measurements showed that basal [DA]out in the SNc was 79.8 ± 10.9 nM in urethane-anesthetized rats, which was enhanced by amphetamine. Overall, our findings indicate that although tonic somatodendritic DA release is largely independent of action potentials, basal [DA]out is strongly regulated by voltage-dependent Ca2+ influx and release of intracellular Ca2+ . OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* because it provided all relevant information to reproduce the study in the manuscript. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/.
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Potenciais de Ação/fisiologia , Sinalização do Cálcio/fisiologia , Dopamina/metabolismo , Neurônios Dopaminérgicos/fisiologia , Parte Compacta da Substância Negra/fisiologia , Animais , Feminino , Masculino , Ratos , Ratos WistarRESUMO
Cortical hyperexcitability is an early and intrinsic feature of Amyotrophic Lateral Sclerosis (ALS), but the mechanisms underlying this critical neuronal dysfunction are poorly understood. Recently, we have demonstrated that layer V pyramidal neurons (PNs) in the primary motor cortex (M1) of one-month old (P30) G93A ALS mice display an early hyperexcitability status compared to Control mice. In order to investigate the time-dependent evolution of the cortical excitability in the G93A ALS model, here we have performed an electrophysiological and immunohistochemical study at three different mouse ages. M1 PNs from 14-days old (P14) G93A mice have shown no excitability alterations, while M1 PNs from 3-months old (P90) G93A mice have shown a hypoexcitability status, compared to Control mice. These age-dependent cortical excitability dysfunctions correlate with a similar time-dependent trend of the persistent sodium current (INaP) amplitude alterations, suggesting that INaP may play a crucial role in the G93A cortical excitability aberrations. Specifically, immunohistochemistry experiments have indicated that the expression level of the NaV1.6 channel, one of the voltage-gated Na+ channels mainly distributed within the central nervous system, varies in G93A primary motor cortex during disease progression, according to the excitability and INaP alterations, but not in other cortical areas. Microfluorometry experiments, combined with electrophysiological recordings, have verified that P30 G93A PNs hyperexcitability is associated to a greater accumulation of intracellular calcium ([Ca2+]i) compared to Control PNs, and that this difference is still present when G93A and Control PNs fire action potentials at the same frequency. These results suggest that [Ca2+]i de-regulation in G93A PNs may contribute to neuronal demise and that the NaV1.6 channels could be a potential therapeutic target to ameliorate ALS disease progression.
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Esclerose Lateral Amiotrófica/metabolismo , Córtex Motor/fisiopatologia , Neurônios Motores/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.6/metabolismo , Potenciais de Ação/fisiologia , Fatores Etários , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/fisiopatologia , Animais , Cálcio/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Regulação da Expressão Gênica , Masculino , Camundongos , Camundongos Transgênicos , Córtex Motor/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.6/genéticaRESUMO
Background Obstructive sleep apnoea (OSA) is an independent risk factor of hypertension and cardiovascular diseases. Recurrent episodes of upper airways collapse during sleep causing blood oxygen desaturation, hypercapnia, and micro-arousals, are known to activate the sympathetic nervous system (SNS). However, whether changes in the renin-angiotensin-aldosterone system and endothelial activation also occur remains contentious. Methods Based on routine use of drug-induced sleep endoscopy (DISE) for the work-up of OSA patients in our centre, we designed a prospective study to investigate the haemodynamic and humoral changes occurring during the apnoeic episodes reproduced in vivo in the course of DISE. Specifically, plasma aldosterone concentration and renin activity, C-terminal fragment of proendothelin-1, as a marker of endothelial damage, and free plasma catecholamines, will be measured at fixed times during DISE. The activity of catechol-O-methyltransferase (COMT), a key catecholamine-inactivating enzyme that has been scantly investigated thus far owing to the lack of commercially available kits, will be also determined by a newly developed high performance liquid chromatography method, which is herein described. Results and conclusions The aim of this study is to provide novel information on the haemodynamic, hormonal, and SNS changes, and also on COMT activity modification concomitantly occurring during apnoea, thus contributing substantively to the understanding of the pathophysiology of OSA.
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Endoscopia/métodos , Apneia Obstrutiva do Sono/metabolismo , Adulto , Aldosterona/análise , Aldosterona/sangue , Catecol O-Metiltransferase/análise , Catecol O-Metiltransferase/sangue , Catecolaminas/análise , Catecolaminas/sangue , Endotelina-1/análise , Endotelina-1/sangue , Humanos , Masculino , Projetos Piloto , Estudos Prospectivos , Precursores de Proteínas/análise , Precursores de Proteínas/sangue , Renina/análise , Renina/sangue , Projetos de Pesquisa , Sono/fisiologia , Apneia Obstrutiva do Sono/fisiopatologiaRESUMO
PURPOSE: To assess preoperative features that could predict the audiological outcome after cochlear implantation in the elderly, in terms of pure tone audiometry, speech audiometry, and speech perception performance. METHODS: All available records of patients with cochlear implants aged 65 or more at the time of their implantation at our Institution were reviewed (50 patients, mean age 70.76 ± 4.03 years), recording preoperative clinical features. Pure tone audiometry, speech audiometry, and speech perception performance 1 year after cochlear implant activation and fitting were used as outcome measures. RESULTS: No statistically significant association emerged between clinical features and pure tone audiometry. On univariate analysis, progressive sensorineural hearing loss of unknown origin was associated with a better outcome in terms of speech audiometry and speech perception performance (p = 0.035 and p = 0.033, respectively). On multivariate analysis, progressive sensorineural hearing loss retained its independent prognostic significance in terms of speech perception performance (p = 0.042). The discriminatory power of a two-variable panel (age and etiology of hearing loss) featured an AUC (ROC) of 0.738 (an acceptable discriminatory power according to the Hosmer-Lemeshow scale). CONCLUSIONS: A progressive sensorineural hearing loss of unknown origin was associated with a better outcome in terms of speech perception in the elderly in our case study. Further features that can predict audiological outcome achievable with cochlear implants in the elderly are desirable to perform adequate counselling and rehabilitation programs.
Assuntos
Audiometria de Tons Puros/métodos , Audiometria da Fala/métodos , Implante Coclear , Perda Auditiva Neurossensorial , Perda Auditiva , Idoso , Implante Coclear/efeitos adversos , Implante Coclear/métodos , Implante Coclear/estatística & dados numéricos , Feminino , Perda Auditiva/classificação , Perda Auditiva/diagnóstico , Perda Auditiva/fisiopatologia , Perda Auditiva/cirurgia , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/fisiopatologia , Perda Auditiva Neurossensorial/cirurgia , Humanos , Masculino , Avaliação de Processos e Resultados em Cuidados de Saúde , Valor Preditivo dos Testes , Prognóstico , Percepção da FalaRESUMO
OBJECTIVES: Nasal obstruction is the most common symptom in nasal diseases. It can be evaluated objectively, that is by means of peak nasal inspiratory flow (PNIF) measures and/or subjectively by means of validated questionnaires. However, it has been reported that there is a lack of reliable correlation between subjective and objective measurements of nasal obstruction. The aim of the present study was to evaluate the correlation between PNIF measurements and the subjective sensation of nasal obstruction measured by means of a visual analogue scale (VAS) in a large population of consecutive rhinologic patients. DESIGN: Prospective clinical study. SETTING: Tertiary rhinological referral centre. PARTICIPANT MAIN OUTCOME MEASURES: A total of 641 consecutive subjects were enrolled. Visual analogue scale and PNIF were performed to assess nasal obstruction. Nasal septal deviation was classified according to Mladina classification, and its severity was assessed using three levels of severity. RESULTS: Although weak, there was a significant negative correlation (r = -0.13, P = 0.001) between PNIF and VAS. Dividing the population in those affected by nasal septal deviation (NSD) and those affected by chronic rhinosinusitis (CRS), a week negative correlation between PNIF and VAS was again confirmed in both groups (r = -0.208, P = 0.006 for NSD and r = -0.13, P = 0.04 for CRS). Peak nasal inspiratory flow and VAS were also evaluated according to the grade of polyps and the type and level of septal deviation. CONCLUSIONS: Visual analogue scale and PNIF significantly correlated, although with a low degree, in a large population of rhinologic patients. Peak nasal inspiratory flow, being cheap and simple to use, could be a good candidate to assist clinicians dealing with "airway" diseases in their daily clinical practice in order to provide comprehensive information on nasal function. Peak nasal inspiratory flow can in fact give some important rough insights on VAS, but these measurements cannot be alternative to each other.
Assuntos
Obstrução Nasal/fisiopatologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Resistência das Vias Respiratórias/fisiologia , Feminino , Humanos , Capacidade Inspiratória/fisiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Escala Visual AnalógicaRESUMO
BACKGROUND: Kanamycin, mainly used in the treatment of drug-resistant-tuberculosis, is known to cause irreversible hearing loss. Using the xeno-transplant model, we compared both in vitro and in vivo characteristics of human mesenchymal stromal cells (MSCs) derived from adult tissues, bone marrow (BM-MSCs) and adipose tissue (ADSCs). These tissues were selected for their availability, in vitro multipotency and regenerative potential in vivo in kanamycin-deafened nod-scid mice. METHODS: MSCs were isolated from informed donors and expanded ex vivo. We evaluated their proliferation capacity in vitro using the hexosaminidase assay, the phenotypic profile using flow-cytometry of a panel of surface antigens, the osteogenic potential using alkaline phosphatase activity and the adipogenic potential using oil-red-O staining. MSCs were intravenously injected in deafened mice and cochleae, liver, spleen and kidney were sampled 7 and 30 days after transplantation. The dissected organs were analyzed using lectin histochemistry, immunohistochemistry, polymerase chain reaction (PCR) and dual color fluorescence in situ hybridization (DC-FISH). RESULTS: MSCs showed similar in vitro characteristics, but ADSCs appeared to be more efficient after prolonged expansion. Both cell types engrafted in the cochlea of damaged mice, inducing regeneration of the damaged sensory structures. Several hybrid cells were detected in engrafted tissues. DISCUSSION: BM-MSCs and ADSCs showed in vitro characteristics suitable for tissue regeneration and fused with resident cells in engrafted tissues. The data suggest that paracrine effect is the prevalent mechanism inducing tissue recovery. Overall, BM-MSCs and ADSCs appear to be valuable tools in regenerative medicine for hearing loss recovery.