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Social interactions have a significant impact on health in humans and animal models. Social isolation initiates a cascade of stress-related physiological disorders and stands as a significant risk factor for a wide spectrum of morbidity and mortality. Indeed, social isolation stress (SIS) is indicative of cognitive decline and risk to neurodegenerative conditions, including Alzheimer's disease (AD). This study aimed to evaluate the impact of chronic, long-term SIS on the propensity to develop hallmarks of AD in young degus (Octodon degus), a long-lived animal model that mimics sporadic AD naturally. We examined inflammatory factors, bioenergetic status, reactive oxygen species (ROS), oxidative stress, antioxidants, abnormal proteins, tau protein, and amyloid-ß (Aß) levels in the hippocampus of female and male degus that were socially isolated from post-natal and post-weaning until adulthood. Additionally, we explored the effect of re-socialization following chronic isolation on these protein profiles. Our results showed that SIS promotes a pro-inflammatory scenario more severe in males, a response that was partially mitigated by a period of re-socialization. In addition, ATP levels, ROS, and markers of oxidative stress are severely affected in female degus, where a period of re-socialization fails to restore them as it does in males. In females, these effects might be linked to antioxidant enzymes like catalase, which experience a decline across all SIS treatments without recovery during re-socialization. Although in males, a previous enzyme in antioxidant pathway diminishes in all treatments, catalase rebounds during re-socialization. Notably, males have less mature neurons after chronic isolation, whereas phosphorylated tau and all detectable forms of Aß increased in both sexes, persisting even post re-socialization. Collectively, these findings suggest that long-term SIS may render males more susceptible to inflammatory states, while females are predisposed to oxidative states. In both scenarios, the accumulation of tau and Aß proteins increase the individual susceptibility to early-onset neurodegenerative conditions such as AD.
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BACKGROUND: During the European Society for Medical Oncology (ESMO) Congress 2022, outcome data of a great number of clinical trials were presented. For the attending medical oncologist, it is important to structure these data in a way that facilitates a trade-off between treatment burden and benefit. MATERIALS AND METHODS: To illustrate this, we carried out a narrative non-systematic review of 12 selected oral presentations with potential impact on future daily practice, focusing on trial methodology, possible study flaws, reported clinical benefit and implementability. RESULTS: The selected presentations encompassed 10 phase III trials, 1 randomized phase II trial and 1 phase II trial. In 7 out of 12 trials, quality of life and/or patient-reported outcomes had been evaluated. None of the trials, which reported progression-free survival (PFS) data, provided information, which could exclude informative censoring bias. In none of the trials reporting overall survival (OS) data, potential flaws due to undesirable crossover and imbalance between study groups regarding post-progression treatments were addressed. For the 11 reviewed randomized trials, the ESMO-Magnitude of Clinical Benefit Scale (MCBS) grade achieved with the new intervention was calculated based on the presented data. The MCBS grade varied from 1 to 5. CONCLUSIONS: Our review confirms the high-quality standard of current cancer research and the clinical relevance of the research questions answered. However, during presentation of PFS and/or OS data, factors known to affect PFS and OS analysis should be structurally addressed. In order to keep cancer care affordable and sustainable, it could be considered to include an ESMO-MCBS threshold in the drug appraisal process of regulatory authorities.
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Oncologia , Neoplasias , Humanos , Ensaios Clínicos Fase II como Assunto , Oncologia/métodos , Intervalo Livre de Progressão , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Sobrevida , Neoplasias/mortalidade , Neoplasias/terapiaRESUMO
Glycine Receptors (GlyRs) are cell-surface transmembrane proteins that belong to the Cysloop ligand-gated ion channels superfamily (Cys-loop LGICs). Functional glycine receptors are conformed only by α-subunits (homomeric channels) or by α- and ß-subunits (heteromeric channels). The role of glycine as a cytoprotective is widely studied. New information about glycine modulation of vascular endothelial cells (ECs) function emerged last year. Glycine and its receptors are recognized to play a role as neurovascular protectors by a mechanism that involves α2GlyRs. Interestingly, the expression of α2GlyRs reduces after stroke injury. However, glycine reverses the inhibition of α2GlyRs by a mechanism involving the VEGF/pSTAT3 signaling. On the other hand, consistent evidence has demonstrated that ECs participate actively in the innate and adaptive immunological response. We recently reported that GlyRs are modulated by interleukin-1ß, suggesting new perspectives to explain the immune modulation of vascular function in pathological conditions such as cerebrovascular stroke. In this work, we distinguish the role of glycine and the allosteric modulation of glycine receptors as a new therapeutic target to confront post-ischemic injury.
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Canais Iônicos de Abertura Ativada por Ligante , Receptores de Glicina , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Glicina/metabolismo , Glicina/farmacologia , Glicina/uso terapêutico , Humanos , Interleucina-1beta/metabolismo , Canais Iônicos de Abertura Ativada por Ligante/metabolismo , Receptores de Glicina/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
This paper extends frequency domain quantitative electroencephalography (qEEG) methods pursuing higher sensitivity to detect Brain Developmental Disorders. Prior qEEG work lacked integration of cross-spectral information omitting important functional connectivity descriptors. Lack of geographical diversity precluded accounting for site-specific variance, increasing qEEG nuisance variance. We ameliorate these weaknesses. (i) Create lifespan Riemannian multinational qEEG norms for cross-spectral tensors. These norms result from the HarMNqEEG project fostered by the Global Brain Consortium. We calculate the norms with data from 9 countries, 12 devices, and 14 studies, including 1564 subjects. Instead of raw data, only anonymized metadata and EEG cross-spectral tensors were shared. After visual and automatic quality control, developmental equations for the mean and standard deviation of qEEG traditional and Riemannian DPs were calculated using additive mixed-effects models. We demonstrate qEEG "batch effects" and provide methods to calculate harmonized z-scores. (ii) We also show that harmonized Riemannian norms produce z-scores with increased diagnostic accuracy predicting brain dysfunction produced by malnutrition in the first year of life and detecting COVID induced brain dysfunction. (iii) We offer open code and data to calculate different individual z-scores from the HarMNqEEG dataset. These results contribute to developing bias-free, low-cost neuroimaging technologies applicable in various health settings.
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Encefalopatias , COVID-19 , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Eletroencefalografia/métodos , HumanosRESUMO
Octodon degus are a diurnal long-lived social animal widely used to perform longitudinal studies and complex cognitive tasks to test for physiological conditions with similitude in human behavior. They show a complex social organization feasible to be studied under different conditions and ages. Several aspects in degus physiology demonstrated that these animals are susceptible to environmental conditions, such as stress, fear, feeding quality, and isolation. However, the relevance of these factors in life of this animal depends on sex and age. Despite its significance, there are few studies with the intent to characterize neurological parameters that include these two parameters. To determine the basal neurophysiological status, we analyzed basic electrophysiological parameters generated during basal activity or synaptic plasticity in the brain slices of young and aged female and male degus. We studied the hippocampal circuit of animals kept in social ambient in captivity under controlled conditions. The study of basal synaptic activity in young animals (12-24 months old) was similar between sexes, but female degus showed more efficient synaptic transmission than male degus. We found the opposite in aged animals (60-84 months old), where male degus had a more efficient basal transmission and facilitation index than female degus. Furthermore, female and male degus develop significant but not different long-term synaptic plasticity (LTP). However, aged female degus need to recruit twice as many axons to evoke the same postsynaptic activity as male degus and four times more when compared to young female degus. These data suggest that, unlike male degus, the neural status of aged female degus change, showing less number or functional axons available at advanced ages. Our data represent the first approach to incorporate the effect of sex along with age progression in basal neural status.
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COVID-19 is a worldwide health emergency, therapy for this disease is based on antiviral drugs and immunomodulators, however, there is no treatment to effectively reduce the COVID-19 mortality rate. Fucoidan is a polysaccharide obtained from marine brown algae, with anti-inflammatory, antiviral, and immune-enhancing properties, thus, fucoidan may be used as an alternative treatment (complementary to prescribed medical therapy) for the recovery of COVID-19. This work aimed to determine the effects of ex-vivo treatment with fucoidan on cytotoxicity, apoptosis, necrosis, and senescence, besides functional parameters of calcium flux and mitochondrial membrane potential (ΔΨm) on human peripheral blood mononuclear cells isolated from SARS-CoV-2 infected, recovered and healthy subjects. Data suggest that fucoidan does not exert cytotoxicity or senescence, however, it induces the increment of intracellular calcium flux. Additionally, fucoidan promotes recovery of ΔΨm in PBMCs from COVID-19 recovered females. Data suggest that fucoidan could ameliorate the immune response in COVID-19 patients.
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Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Feminino , Humanos , Leucócitos Mononucleares , Cálcio , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêuticoRESUMO
Interleukin-1ß (IL-1ß) is an important cytokine that modulates peripheral and central pain sensitization at the spinal level. Among its effects, it increases spinal cord excitability by reducing inhibitory Glycinergic and GABAergic neurotransmission. In the brain, IL-1ß is released by glial cells in regions associated with pain processing during neuropathic pain. It also has important roles in neuroinflammation and in regulating NMDA receptor activity required for learning and memory. The modulation of glycine-mediated inhibitory activity via IL-1ß may play a critical role in the perception of different levels of pain. The central nucleus of the amygdala (CeA) participates in receiving and processing pain information. Interestingly, this nucleus is enriched in the regulatory auxiliary glycine receptor (GlyR) ß subunit (ßGlyR); however, no studies have evaluated the effect of IL-1ß on glycinergic neurotransmission in the brain. Hence, we hypothesized that IL-1ß may modulate GlyR-mediated inhibitory activity via interactions with the ßGlyR subunit. Our results show that the application of IL-1ß (10 ng/ml) to CeA brain slices has a biphasic effect; transiently increases and then reduces sIPSC amplitude of CeA glycinergic currents. Additionally, we performed molecular docking, site-directed mutagenesis, and whole-cell voltage-clamp electrophysiological experiments in HEK cells transfected with GlyRs containing different GlyR subunits. These data indicate that IL-1ß modulates GlyR activity by establishing hydrogen bonds with at least one key amino acid residue located in the back of the loop C at the ECD domain of the ßGlyR subunit. The present results suggest that IL-1ß in the CeA controls glycinergic neurotransmission, possibly via interactions with the ßGlyR subunit. This effect could be relevant for understanding how IL-1ß released by glia modulates central processing of pain, learning and memory, and is involved in neuroinflammation.
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Stuck and sluggish fermentations are among the main problems in winemaking industry leading to important economic losses. Several factors have been described as causes of stuck and sluggish fermentations, being exposure to extreme temperatures barely studied. The objective of this study was to identify thermal conditions leading to stuck and sluggish fermentations, focusing on the impact of an abrupt and transient decrease/increase of temperature on fermentation performance and yeast viability/vitality. Different strains of Saccharomyces cerevisiae, SBB11, T73, and PDM were evaluated in synthetic grape must fermentations. Cold shocks (9⯰C and 1.5⯰C for 16â¯h) carried out on different days during the fermentation process were unable to alter fermentation performance. Conversely, shock temperatures higher than 32⯰C, applied in early stages of the process, lead to sluggish fermentation showing a delay directly related to the temperature increase. Fermentation delay was associated with a decrease in cell vitality. The impact of the heat shock on fermentation performance was different depending on the strain evaluated and nitrogen supplementation (with or without diammonium phosphate addition). None of the conditions evaluated produced a stuck fermentation and importantly, in all cases must nutrition improved fermentation performance after a heat shock.
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Temperatura Baixa , Fermentação/fisiologia , Temperatura Alta , Saccharomyces cerevisiae/metabolismo , Resposta ao Choque Frio/fisiologia , Resposta ao Choque Térmico/fisiologia , Fosfatos/farmacologia , Vitis/metabolismo , Vinho/análiseRESUMO
INTRODUCTION: Increasing evidence suggests that changes in the balance of excitatory/inhibitory neurotransmission are involved in the development of the majority of chronic pain forms. In this context, impairment in glycine mediated inhibitory neurotransmission is thought to play a critical role in the disinhibition that accounts for the development and maintenance of central pain hypersensitivity. AIMS: The goal of this study was to evaluate the Glycine Receptor α3 subunit (α3GlyR) expression in neuropathic (Chronic Constriction Injury, CCI) and inflammatory (Zymosan A injected) animal models of chronic pain. RESULTS AND CONCLUSION: RT-qPCR analysis of spinal cord samples showed that glra3 gene expression does not change after 3 days of CCI and 4 hours of Zymosan A injection. However, we found that protein levels evaluated by Western blot increased after inflammatory pain. These data suggest that central sensitization is differentially regulated depending on the type of pain. α3GlyR protein expression plays an important role in the first step of inflammatory pain establishment.
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Animais , Receptores de Glicina/metabolismo , Receptores de Glicina/agonistas , Sensibilização do Sistema Nervoso Central/fisiologia , Dor/diagnóstico , Dor/fisiopatologia , Zimosan/administração & dosagem , Medição da Dor/métodos , Análise de Variância , Receptores de Glicina/química , Reação em Cadeia da Polimerase em Tempo Real/métodosRESUMO
RAS signalling is involved in the control of several metabolic pathways including glycolysis, mitochondrial respiration and glutamine metabolism. Importantly, we have found here that loss of PDHK4, a key regulator of the pyruvate dehydrogenase complex, caused a profound cell growth inhibition in tumour cells harbouring KRAS mutations. Using isogenic cells and a panel of colorectal and lung cell lines we demonstrated that KRAS mutant cells showed a dependency on PDHK4 whereas KRAS wild-type cells were significantly resistant to PDHK4 knockdown. We have found that PDHK4 plays a role in the post-translational regulation of mutant KRAS activity. Depletion of PDHK4 causes disruption of KRAS cellular localization, a reduction in KRAS activity which, in turn, results in reduced MAPK signalling. Interestingly, PDHK4 and KRAS depletion resulted in a similar metabolic phenotype consisting of a reduction of glucose and fatty acid oxidation. Moreover, stable expression of PDHK4 increased localization of activated KRAS at the plasma membrane and induced tumour cell growth in vitro and in vivo. Taken together these data support a model where PDHK4 regulates KRAS signalling and its tumorigenic properties and suggest that inhibition of PDHK4 could represent a novel therapeutic strategy to target KRAS mutant colorectal and lung cancers.
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Neoplasias Colorretais/genética , Neoplasias Pulmonares/genética , Proteínas Quinases/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pulmonares/patologia , Mutação , Transdução de Sinais/genéticaRESUMO
BACKGROUND AND PURPOSE: Gelsemine is one of the principal alkaloids produced by the Gelsemium genus of plants belonging to the Loganiaceae family. The extracts of these plants have been used for many years, for a variety of medicinal purposes. Coincidentally, recent studies have shown that gelsemine exerts anxiolytic and analgesic effects on behavioural models. Several lines of evidence have suggested that these beneficial actions were dependent on glycine receptors, which are inhibitory neurotransmitter-gated ion channels of the CNS. However, it is currently unknown whether gelsemine can directly modulate the function of glycine receptors. EXPERIMENTAL APPROACH: We examined the functional effects of gelsemine on glycine receptors expressed in transfected HEK293 cells and in cultured spinal neurons by electrophysiological techniques. KEY RESULTS: Gelsemine directly modulated recombinant and native glycine receptors and exerted conformation-specific and subunit-selective effects. Gelsemine modulation was voltage-independent and was associated with differential changes in the apparent affinity for glycine and in the open probability of the ion channel. In addition, the alkaloid preferentially targeted glycine receptors in spinal neurons and showed only minor effects on GABAA and AMPA receptors. Furthermore, gelsemine significantly diminished the frequency of glycinergic and glutamatergic synaptic events without altering the amplitude. CONCLUSIONS AND IMPLICATIONS: Our results provide a pharmacological basis to explain, at least in part, the glycine receptor-dependent, beneficial and toxic effects of gelsemine in animals and humans. In addition, the pharmacological profile of gelsemine may open new approaches to the development of subunit-selective modulators of glycine receptors.
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Alcaloides/farmacologia , Receptores de Glicina/metabolismo , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Receptores de Glicina/química , Relação Estrutura-AtividadeRESUMO
Objetivo: Determinar la asociación entre los factores sociales, fisiológicos y el riesgo de evento cardiovascular según el Framingham Risk Score, en taxistas de una empresa de transportes de la ciudad de Huancayo-Perú. Metodología: Se realizó un estudio analítico transversal observacional en taxistas de una empresa de transportes de Huancayo, mediante un muestreo no probabilístico. Se recolectó los datos para generar el Score de Framingham (versión de 1991), calculando el riesgo cardiovascular a 10 años, además de recolectar otras variables como la actividad física, alimentación, consumo de bebidas alcohólicas, antecedentes familiares y el nivel de triglicéridos. Se obtuvo los valores p. Resultados: El riesgo de padecer un evento cardiovascular a 10 años, según las tablas Framingham es bajo en el 88% de los casos. El valor de la glucosa en ayunas resultó estadísticamente diferente entre los que tenían una categoría elevada de riesgo cardiovascular (p=0,013), además, el tener diagnóstico de diabetes también fue estadísticamente diferente (p=0,027). Conclusión: Existe un nivel bajo de riesgo cardiovascular a 10 años en taxistas de la ciudad de Huancayo. Estos hallazgos pueden ayudar a la Salud Pública y Ocupacional, para cuidar a este tipo de poblaciones que tienen un riesgo y que podría repercutir tanto en la morbilidad como en la mortalidad a futuro (AU)
Aim: To determine the association between social, physiological factors and the risk of cardiovascular event according to the Framingham Risk Score, in taxi drivers of a transport company in the city of HuancayoPeru. Methodology: An observational cross-sectional study in a taxi transport company of Huancayo was performed, by a non-probability sampling. Data were collected to generate the Framingham Score (version 1991), calculating the cardiovascular risk within 10 years, in addition to collect other variables such as physical activity, diet, alcohol consumption, family history and triglycerides. P values were obtained. Results: The risk of suffering a cardiovascular event within 10 years, according to the Framingham tables is low in 88% of cases. The value of fasting glucose was statistically different between those with a high category of cardiovascular risk (p = 0.013) in addition, having diagnosed diabetes was also statistically different (p = 0.027). Conclusions: There is a low level of cardiovascular risk at 10 years in taxi drivers in the city of Huancayo. These findings may help Public and Occupational Health, to care for these populations that are at risk and that could have an impact on morbidity and mortality in the future (AU)
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Humanos , Masculino , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/prevenção & controle , Algoritmos , Saúde Ocupacional , Saúde Pública , Estudos Transversais/instrumentação , Estudos Transversais/métodos , Estudos Transversais , Estudo Observacional , PeruRESUMO
INTRODUCTION: Cisplatin is a commonly prescribed drug that produces ototoxicity as a side effect. Lutein is a carotenoid with antioxidant and anti-inflammatory properties previously tested for eye, heart and skin diseases but not evaluated to date in ear diseases. AIM: To evaluate the protective effects of lutein on HEI-OC1 auditory cell line and in a Wistar rat model of cisplatin ototoxicity. MATERIALS AND METHODS: In vitro study: Culture HEI-OC1 cells were exposed to lutein (2.5-100 µM) and to 25 µM cisplatin for 24h. In vivo study: Twenty eight female Wistar rats were randomized into three groups. Group A (n=8) received intratympanic lutein (0.03 mL) (1mg/mL) in the right ear and saline solution in the left one to determine the toxicity of lutein. Group B (n=8) received also intraperitoneal cisplatin (10mg/kg) to test the efficacy of lutein against cisplatin ototoxicity. Group C (n=12) received intratympanic lutein (0.03 mL) (1mg/mL) to quantify lutein in cochlear fluids (30 min, 1h and 5 days after treatment). Hearing function was evaluated by means of Auditory Steady-State Responses before the procedure and 5 days after (groups A and B). Morphological changes were studied by confocal laser scanning microscopy. RESULTS: In vitro study: Lutein significantly reduced the cisplatin-induced cytotoxicity in the HEI-OC1 cells when they were pre-treated with lutein concentrations of 60 and 80 µM. In vivo study: Intratympanic lutein (1mg/mL) application showed no ototoxic effects. However it did not achieve protective effect against cisplatin-induced ototoxicity in Wistar rats. CONCLUSIONS: Although lutein has shown beneficial effects in other pathologies, the present study only obtained protection against cisplatin ototoxicity in culture cells, but not in the in vivo model. The large molecule size, the low dose administered, and restriction to diffusion in the inner ear could account for this negative result.
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Antineoplásicos/toxicidade , Limiar Auditivo/efeitos dos fármacos , Cisplatino/toxicidade , Células Ciliadas Auditivas/efeitos dos fármacos , Luteína/farmacologia , Substâncias Protetoras/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Células Ciliadas Auditivas/patologia , Luteína/toxicidade , Camundongos , Substâncias Protetoras/toxicidade , Ratos WistarRESUMO
Temephos is an organophosphorus pesticide that is used in control campaigns against Aedes aegypti mosquitoes, which transmit dengue. In spite of the widespread use of temephos, few studies have examined its genotoxic potential. The aim of this study was to evaluate the cytotoxic, cytostatic and genotoxic effects of temephos in human lymphocytes and hepatoma cells (HepG2). The cytotoxicity was evaluated with simultaneous staining (FDA/EtBr). The cytostatic and genotoxic effects were evaluated using comet assays and the micronucleus technique. We found that temephos was not cytotoxic in either lymphocytes or HepG2 cells. Regarding the cytostatic effect in human lymphocytes, temephos (10 µM) caused a significant decrease in the percentage of binucleated cells and in the nuclear division index as well as an increase in the apoptotic cell frequency, which was not the case for HepG2 cells. The comet assay showed that temephos increased the DNA damage levels in human lymphocytes, but it did not increase the MN frequency. In contrast, in HepG2 cells, temephos increased the tail length, tail moment and MN frequency in HepG2 cells compared to control cells. In conclusion, temephos causes stable DNA damage in HepG2 cells but not in human lymphocytes. These findings suggest the importance of temephos biotransformation in its genotoxic effect.
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Linfócitos/efeitos dos fármacos , Mutagênicos/toxicidade , Temefós/toxicidade , Adolescente , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Ensaio Cometa , Citocinese/efeitos dos fármacos , Células Hep G2 , Humanos , Inseticidas/toxicidade , Masculino , Testes para Micronúcleos , Adulto JovemRESUMO
OBJECTIVE: To determine common reference equivalent threshold sound pressure levels (RETSPL) for the earphones used in the extended high-frequency (EHF) range, as different earphones are commercially available, but there are not RETSPLs for each model. DESIGN: Hearing threshold sound pressure levels were measured up to 20 kHz for the Sennheiser HDA 200 audiometric earphone, and were compared to the ISO 389-5 (2006) norm and other investigations using that earphone and different ones. STUDY SAMPLE: A total of 223 otologically-normal subjects (aged 5-25 years old) participated in the hearing determination. RESULTS: The results are in good agreement with previous studies of hearing thresholds using the same and other earphones. CONCLUSIONS: The results of the present investigation are relevant for the international standard for the calibration of audiometric equipment in the 8 to 16 kHz frequency range, ISO 389-5. The data may be used for a future update of the RETSPL for circumaural and insert audiometric earphones.
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Estimulação Acústica/instrumentação , Acústica/instrumentação , Audiometria de Tons Puros/instrumentação , Vias Auditivas/fisiologia , Limiar Auditivo , Percepção da Altura Sonora , Adolescente , Adulto , Fatores Etários , Calibragem , Criança , Pré-Escolar , Desenho de Equipamento , Feminino , Humanos , Masculino , Pressão , Valores de Referência , Som , Adulto JovemRESUMO
OBJECTIVE: The aim of the present study was to study patterns in the extended spectrum of the human hearing (0.125 to 20 kHz) in order to obtain reference thresholds. Then, we compare our values with existing results at extended high-frequencies (8 to 20 kHz) in an attempt to establish new standards for potential international adoption. DESIGN: A prospective study in a group of otologically healthy subjects. STUDY SAMPLE: A total of 645 subjects aged between 5 and 90 years were recruited. Pure-tone thresholds were determined for conventional and extended high-frequencies. RESULTS: There was an increase in the hearing thresholds as a function of frequency and age. For the 20 to 69 years old group, thresholds were lower in females than in males, especially at 12.5 and 16 kHz. Our threshold values are comparable to those presented in previous studies that used different instrumentation and populations. CONCLUSIONS: When comparing different studies the hearing thresholds were found to be similar. Therefore, it would be possible to establish international standard thresholds.
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Audiometria de Tons Puros/normas , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Adulto JovemRESUMO
Although dimethyl sulfoxide (DMSO) is one of the most common solvents employed in otoprotection studies, its effect on the inner ear remains unknown. Only a few in vitro studies have addressed the effect of DMSO in cochlear cells. Up to the date, no in vivo functional studies have been reported. To determine the effect of intratympanic DMSO application in the inner ear, and to evaluate its effect in combination with cisplatin in Wistar rats, twelve Wistar rats were randomly assigned into two groups. Group A received intratympanic 1 % DMSO in both ears. Group B received intraperitoneal cisplatin (10 mg/kg) and intratympanic 0.5 % DMSO in the right ear and saline solution in the left ear. Functional changes were evaluated with Auditory Steady-State Responses before and 5 days after the procedure. Morphological changes were studied by means of confocal laser scanning microscopy following the removal of the temporal bones and cochlear dissection. Hearing threshold levels in group A did not show any statistically significant changes after the treatment. In group B, significant differences between pre- and post-treatment were found, with no statistically significant variations between right (DMSO) and left ear (saline solution). We suggest that DMSO could be safely used to dissolve hydrophobic compounds in otoprotection studies without interfering with the cochlear damage produced by cisplatin.
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Cisplatino/toxicidade , Cóclea , Dimetil Sulfóxido/farmacologia , Animais , Antineoplásicos/farmacologia , Cóclea/efeitos dos fármacos , Cóclea/patologia , Citoproteção , Masculino , Substâncias Protetoras/farmacologia , Ratos , Ratos WistarRESUMO
Ethanol increased the frequency of miniature glycinergic currents [miniature inhibitory postsynaptic currents (mIPSCs)] in cultured spinal neurons. This effect was dependent on intracellular calcium augmentation, since preincubation with BAPTA (an intracellular calcium chelator) or thapsigargin [a sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA) pump inhibitor] significantly attenuated this effect. Similarly, U73122 (a phospholipase C inhibitor) or 2-aminoethoxydiphenyl borate [2-APB, an inositol 1,4,5-trisphosphate (IP3) receptor (IP3R) inhibitor] reduced this effect. Block of ethanol action was also achieved after preincubation with Rp-cAMPS, inhibitor of the adenylate cyclase (AC)/PKA signaling pathway. These data suggest that there is a convergence at the level of IP3R that accounts for presynaptic ethanol effects. At the postsynaptic level, ethanol increased the decay time constant of mIPSCs in a group of neurons (30 ± 10% above control, n = 13/26 cells). On the other hand, the currents activated by exogenously applied glycine were consistently potentiated (55 ± 10% above control, n = 11/12 cells), which suggests that ethanol modulates synaptic and nonsynaptic glycine receptors (GlyRs) in a different fashion. Supporting the role of G protein modulation on ethanol responses, we found that a nonhydrolyzable GTP analog [guanosine 5'-O-(3-thiotriphosphate) (GTPγS)] increased the decay time constant in â¼50% of the neurons (28 ± 12%, n = 11/19 cells) but potentiated the glycine-activated Cl(-) current in most of the neurons examined (83 ± 29%, n = 7/9 cells). In addition, confocal microscopy showed that α1-containing GlyRs colocalized with Gß and Piccolo (a presynaptic cytomatrix protein) in â¼40% of synaptic receptor clusters, suggesting that colocalization of Gßγ and GlyRs might account for the difference in ethanol sensitivity at the postsynaptic level.
Assuntos
Depressores do Sistema Nervoso Central/farmacologia , Etanol/farmacologia , Glicina/metabolismo , Neurônios/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Inibidores de Adenilil Ciclases , Adenilil Ciclases/metabolismo , Animais , Cálcio/metabolismo , Células Cultivadas , Canais de Cloreto/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Guanosina Trifosfato/análogos & derivados , Guanosina Trifosfato/metabolismo , Potenciais Pós-Sinápticos Inibidores/efeitos dos fármacos , Receptores de Inositol 1,4,5-Trifosfato/antagonistas & inibidores , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Camundongos Endogâmicos C57BL , Potenciais Pós-Sinápticos em Miniatura/efeitos dos fármacos , Neurônios/fisiologia , Terminações Pré-Sinápticas/efeitos dos fármacos , Terminações Pré-Sinápticas/fisiologia , Receptores de Glicina/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/antagonistas & inibidores , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Medula Espinal/fisiologia , Transmissão Sináptica/fisiologia , Fosfolipases Tipo C/antagonistas & inibidores , Fosfolipases Tipo C/metabolismoRESUMO
Tumour-derived mutant p53 proteins promote invasion, in part, by enhancing Rab coupling protein (RCP)-dependent receptor recycling. Here we identified MET as an RCP-binding protein and showed that mutant p53 promoted MET recycling. Mutant p53-expressing cells were more sensitive to hepatocyte growth factor, the ligand for MET, leading to enhanced MET signalling, invasion and cell scattering that was dependent on both MET and RCP. In cells expressing the p53 family member TAp63, inhibition of TAp63 also lead to cell scattering and MET-dependent invasion. However, in cells that express very low levels of TAp63, the ability of mutant p53 to promote MET-dependent cell scattering was independent of TAp63. Taken together, our data show that mutant p53 can enhance MET signalling to promote cell scattering and invasion through both TAp63-dependent and -independent mechanisms. MET has a predominant role in metastatic progression and the identification of mechanisms through which mutations in p53 can drive MET signalling may help to identify and direct therapy.
Assuntos
Mutação , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Movimento Celular , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Células HCT116 , Células HT29 , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Invasividade Neoplásica , Fosforilação , Transdução de Sinais , Fatores de Transcrição/metabolismo , Transfecção , Proteínas Supressoras de Tumor/metabolismoRESUMO
OBJECTIVE: To evaluate patients with systemic lupus erythematosus and normal hearing over 10 years, compared with healthy controls. METHODS: Thirty patients diagnosed with systemic lupus erythematosus were evaluated in a prospective, descriptive study. Eight patients fulfilled the inclusion criteria, i.e. normal otoscopy, normal hearing, normal imaging and disease duration of less than one year. Eleven healthy companions of ENT patients were recruited as controls. RESULTS: At study commencement, the mean patient age was 32.75 years (range, 15-49 years) and there were no statistically significant audiometric differences between patients and controls. No statistically significant audiometric changes were found either within or between the patient and control groups at 10-year follow up. CONCLUSION: These results supply no evidence for progressive hearing loss in systemic lupus erythematosus patients with no hearing involvement at study commencement. Therefore, we recommend audiometric tests only for systemic lupus erythematosus patients complaining of hearing loss, or for other clinical purposes. It is conceivable that asymptomatic hearing loss could be observed over a more extended follow-up period (i.e. more than 10 years).