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OBJECTIVE: In daily life, failure to perceive emotional expressions can result in maladjusted behaviour. For cochlear implant users, perceiving emotional cues in sounds remains challenging, and the factors explaining the variability in patients' sensitivity to emotions are currently poorly understood. Understanding how these factors relate to auditory proficiency is a major challenge of cochlear implant research and is critical in addressing patients' limitations. DESIGN: To fill this gap, we evaluated different auditory perception aspects in implant users (pitch discrimination, music processing and speech intelligibility) and correlated them to their performance in an emotion recognition task. STUDY SAMPLE: Eighty-four adults (18-76 years old) participated in our investigation; 42 cochlear implant users and 42 controls. Cochlear implant users performed worse than their controls on all tasks, and emotion perception abilities were correlated to their age and their clinical outcome as measured in the speech intelligibility task. RESULTS: As previously observed, emotion perception abilities declined with age (here by about 2-3% in a decade). Interestingly, even when emotional stimuli were musical, CI users' skills relied more on processes underlying speech intelligibility. CONCLUSIONS: These results suggest that speech processing remains a clinical priority even when one is interested in affective skills.
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Implantación Coclear , Implantes Cocleares , Sordera , Música , Percepción del Habla , Adulto , Humanos , Adolescente , Adulto Joven , Persona de Mediana Edad , Anciano , Sordera/rehabilitación , Percepción Auditiva , Emociones , Inteligibilidad del Habla , Percepción de la Altura TonalRESUMEN
Coagulation management in the patient with cirrhosis has undergone a significant transformation since the beginning of this century, with the concept of a rebalancing between procoagulant and anticoagulant factors. The paradigm that patients with cirrhosis have a greater bleeding tendency has changed, as a result of this rebalancing. In addition, it has brought to light the presence of complications related to thrombotic events in this group of patients. These guidelines detail aspects related to pathophysiologic mechanisms that intervene in the maintenance of hemostasis in the patient with cirrhosis, the relevance of portal hypertension, mechanical factors for the development of bleeding, modifications in the hepatic synthesis of coagulation factors, and the changes in the reticuloendothelial system in acute hepatic decompensation and acute-on-chronic liver failure. They address new aspects related to the hemorrhagic complications in patients with cirrhosis, considering the risk for bleeding during diagnostic or therapeutic procedures, as well as the usefulness of different tools for diagnosing coagulation and recommendations on the pharmacologic treatment and blood-product transfusion in the context of hemorrhage. These guidelines also update the knowledge regarding hypercoagulability in the patient with cirrhosis, as well as the efficacy and safety of treatment with the different anticoagulation regimens. Lastly, they provide recommendations on coagulation management in the context of acute-on-chronic liver failure, acute liver decompensation, and specific aspects related to the patient undergoing liver transplantation.
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Insuficiencia Hepática Crónica Agudizada , Trastornos de la Coagulación Sanguínea , Humanos , Insuficiencia Hepática Crónica Agudizada/complicaciones , Trastornos de la Coagulación Sanguínea/complicaciones , Trastornos de la Coagulación Sanguínea/terapia , Cirrosis Hepática/complicaciones , Cirrosis Hepática/terapia , Coagulación Sanguínea , HemostasisRESUMEN
Introduction: Spider venoms are a unique source of bioactive peptides, many of which display remarkable biological stability and neuroactivity. Phoneutria nigriventer, often referred to as the Brazilian wandering spider, banana spider or "armed" spider, is endemic to South America and amongst the most dangerous venomous spiders in the world. There are 4,000 envenomation accidents with P. nigriventer each year in Brazil, which can lead to symptoms including priapism, hypertension, blurred vision, sweating, and vomiting. In addition to its clinical relevance, P. nigriventer venom contains peptides that provide therapeutic effects in a range of disease models. Methods: In this study, we explored the neuroactivity and molecular diversity of P. nigriventer venom using fractionation-guided high-throughput cellular assays coupled to proteomics and multi-pharmacology activity to broaden the knowledge about this venom and its therapeutic potential and provide a proof-of-concept for an investigative pipeline to study spider-venom derived neuroactive peptides. We coupled proteomics with ion channel assays using a neuroblastoma cell line to identify venom compounds that modulate the activity of voltage-gated sodium and calcium channels, as well as the nicotinic acetylcholine receptor. Results: Our data revealed that P. nigriventer venom is highly complex compared to other neurotoxin-rich venoms and contains potent modulators of voltage-gated ion channels which were classified into four families of neuroactive peptides based on their activity and structures. In addition to the reported P. nigriventer neuroactive peptides, we identified at least 27 novel cysteine-rich venom peptides for which their activity and molecular target remains to be determined. Discussion: Our findings provide a platform for studying the bioactivity of known and novel neuroactive components in the venom of P. nigriventer and other spiders and suggest that our discovery pipeline can be used to identify ion channel-targeting venom peptides with potential as pharmacological tools and to drug leads.
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INTRODUCTION: The sofosbuvir-velpatasvir (SOF/VEL) combination is a direct-acting antiviral therapy that is authorized and available in Mexico, making the performance of a real-world multicenter study that evaluates the sustained virologic response at 12 weeks post-treatment a relevant undertaking. METHODS: A retrospective review of the case records of 241 patients seen at 20 hospitals in Mexico was conducted to assess hepatitis C treatment with the SOF/VEL combination (nâ¯=â¯231) and the sofosbuvir/velpatasvir/ribavirin (SOF/VEL/RBV) combination (nâ¯=â¯10). The primary efficacy endpoint was the percentage of patients that achieved SVR at 12 weeks after the end of treatment. RESULTS: Overall SVR was 98.8% (95% CI 97.35-100%). Only three patients did not achieve SVR, two of whom had cirrhosis and a history of previous treatment with peg-IFN. Of the subgroups analyzed, all the patients with HIV coinfection, three patients with genotype 3, and the patients treated with the SOF/VEL/RBV combination achieved SVR. The subgroups with the lower success rates were patients that were treatment-experienced (96.8%) and patients with F1 fibrosis (95.5%). The most frequent adverse events were fatigue, headache, and insomnia. No serious adverse events were reported. CONCLUSION: Treatments with SOF/VEL and SOF/VEL/RBV were highly safe and effective, results coinciding with those of other international real-world studies.
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Hepatitis C Crónica , Hepatitis C , Antivirales/efectos adversos , Carbamatos , Genotipo , Hepatitis C/tratamiento farmacológico , Hepatitis C Crónica/tratamiento farmacológico , Compuestos Heterocíclicos de 4 o más Anillos , Humanos , México , Estudios Retrospectivos , Sofosbuvir/efectos adversosRESUMEN
The term cholestasis refers to bile acid retention, whether within the hepatocyte or in the bile ducts of any caliber. Biochemically, it is defined by a level of alkaline phosphatase that is 1.67-times higher than the upper limit of normal. Cholestatic diseases can be associated with an inflammatory process of the liver that destroys hepatocytes (hepatitis), withjaundice (yellowing of the skin and mucus membranes, associated with elevated serum bilirubin levels), or with both, albeit the three concepts should not be considered synonymous. Cholestatic diseases can be classified as intrahepatic or extrahepatic, depending on their etiology. Knowing the cause of the condition is important for choosing the adequate diagnostic studies and appropriate treatment in each case. A complete medical history, together with a thorough physical examination and basic initial studies, such as liver ultrasound and liver function tests, aid the clinician in deciding which path to follow, when managing the patient with cholestasis. In a joint effort, the Asociación Mexicana de Hepatología (AMH), the Asociación Mexicana de Gastroenterología (AMG) and the Asociación Mexicana de Endoscopia Gastrointestinal (AMEG) developed the first Mexican scientific position statement on said theme.
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Colestasis , Ictericia , Conductos Biliares , Colestasis/diagnóstico , Humanos , Ictericia/diagnóstico , Hígado , Pruebas de Función HepáticaRESUMEN
INTRODUCTION: The sofosbuvir-velpatasvir (SOF/VEL) combination is a direct-acting antiviral therapy that is authorized and available in Mexico, making the performance of a real-world multicenter study that evaluates the sustained virologic response at 12 weeks post-treatment a relevant undertaking. METHODS: A retrospective review of the case records of 241 patients seen at 20 hospitals in Mexico was conducted to assess hepatitis C treatment with the SOF/VEL combination (n = 231) and the sofosbuvir/velpatasvir/ribavirin (SOF/VEL/RBV) combination (n = 10). The primary efficacy endpoint was the percentage of patients that achieved SVR at 12 weeks after the end of treatment. RESULTS: Overall SVR was 98.8% (95% CI 97.35-100%). Only three patients did not achieve SVR, two of whom had cirrhosis and a history of previous treatment with peg-IFN. Of the subgroups analyzed, all the patients with HIV coinfection, three patients with genotype 3, and the patients treated with the SOF/VEL/RBV combination achieved SVR. The subgroups with the lower success rates were patients that were treatment-experienced (96.8%) and patients with F1 fibrosis (95.5%). The most frequent adverse events were fatigue, headache, and insomnia. No serious adverse events were reported. CONCLUSION: Treatments with SOF/VEL and SOF/VEL/RBV were highly safe and effective, results coinciding with those of other international real-world studies.
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Hepatitis B virus (HBV) infection continues to be a worldwide public health problem. In Mexico, at least three million adults are estimated to have acquired hepatitis B (total hepatitis B core antibody [anti-HBc]-positive), and of those, 300,000 active carriers (hepatitis B surface antigen [HBsAg]-positive) could require treatment. Because HBV is preventable through vaccination, its universal application should be emphasized. HBV infection is a major risk factor for developing hepatocellular carcinoma. Semi-annual liver ultrasound and serum alpha-fetoprotein testing favor early detection of that cancer and should be carried out in all patients with chronic HBV infection, regardless of the presence of advanced fibrosis or cirrhosis. Currently, nucleoside/nucleotide analogues that have a high barrier to resistance are the first-line therapies.
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Hepatitis B Crónica , Neoplasias Hepáticas , Adulto , Antivirales/uso terapéutico , Antígenos de Superficie de la Hepatitis B/uso terapéutico , Virus de la Hepatitis B , Hepatitis B Crónica/diagnóstico , Humanos , Neoplasias Hepáticas/diagnósticoRESUMEN
Hepatitis B virus (HBV) infection continues to be a worldwide public health problem. In Mexico, at least three million adults are estimated to have acquired hepatitis B (total hepatitis B core antibody [anti-HBc]-positive), and of those, 300,000 active carriers (hepatitis B surface antigen [HBsAg]-positive) could require treatment. Because HBV is preventable through vaccination, its universal application should be emphasized. HBV infection is a major risk factor for developing hepatocellular carcinoma. Semi-annual liver ultrasound and serum alpha-fetoprotein testing favor early detection of that cancer and should be carried out in all patients with chronic HBV infection, regardless of the presence of advanced fibrosis or cirrhosis. Currently, nucleoside/nucleotide analogues that have a high barrier to resistance are the first-line therapies.
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Studies revealed that the venom of the Brazilian "armed" spider Phoneutria nigriventer contains potent neurotoxins that caused excitatory symptoms such as salivation, lachrymation, priapism, convulsions, flaccid and spastic paralysis. It was also reported that the main mechanism of action of those neurotoxins are effects on ion channels such as inhibition of the inactivation of Na+ channels, blockage of K+ channels and blockage of calcium channels. The venom from Phoneutria keyserlingi, as might be expected, contains a series of polypeptides that are very similar, but not identical, to the proteins previously obtained from the venom of P. nigriventer in terms of their amino acid sequences and biological activities. We evaluated the effects of some of the toxins of P. nigriventer and P. keyserlingi on glutamate release and the decrease in [Ca2+]i by using synaptosomes of rat brain cortices and fluorimetric assays. Sequence comparisons between the Phoneutria toxins of both the species showed great similarity in the location of cysteine residues. However, thus far, no pharmacological assays were performed to evaluate the extension of those biochemical modifications. Our results showed that differences between the amino acid sequences of Phoneutria toxins of both the species lead to the significant changes in the pharmacological properties of these toxins.
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Calcio/metabolismo , Ácido Glutámico/metabolismo , Venenos de Araña/farmacología , Sinaptosomas/metabolismo , Secuencia de Aminoácidos , Animales , Canales de Calcio/metabolismo , Fluorometría , Canales Iónicos/antagonistas & inhibidores , Canales Iónicos/metabolismo , Datos de Secuencia Molecular , Canales de Potasio/metabolismo , Ratas , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Canales de Sodio/metabolismo , Arañas/metabolismoRESUMEN
Alcoholic hepatitis is a frequent condition in the Mexican population. It is characterized by acute-on-chronic liver failure, important systemic inflammatory response, and multiple organ failure. The severe variant of the disease implies elevated mortality. Therefore, the Asociación Mexicana de Gastroenterología and the Asociación Mexicana de Hepatología brought together a multidisciplinary team of health professionals to formulate the first Mexican consensus on alcoholic hepatitis, carried out utilizing the Delphi method and resulting in 37 recommendations. Alcohol-related liver disease covers a broad spectrum of pathologies that includes steatosis, steatohepatitis, different grades of fibrosis, and cirrhosis and its complications. Severe alcoholic hepatitis is defined by a modified Maddrey's discriminant function score ≥ 32 or by a Model for End-Stage Liver Disease (MELD) score equal to or above 21. There is currently no specific biomarker for its diagnosis. Leukocytosis with neutrophilia, hyperbilirubinemia (> 3 mg/dL), AST > 50 U/l (< 400 U/l), and an AST/ALT ratio > 1.5-2 can guide the diagnosis. Abstinence from alcohol, together with nutritional support, is the cornerstone of treatment. Steroids are indicated for severe disease and have been effective in reducing the 28-day mortality rate. At present, liver transplantation is the only life-saving option for patients that are nonresponders to steroids. Certain drugs, such as N-acetylcysteine, granulocyte-colony stimulating factor, and metadoxine, can be adjuvant therapies with a positive impact on patient survival.
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Hepatitis Alcohólica/diagnóstico , Hepatitis Alcohólica/terapia , Humanos , MéxicoRESUMEN
It has been suggested that overexpression of neuronal Ca2+ sensor-1 (NCS-1) protein is implicated in the pathophysiology of neurodisorders such as schizophrenia, bipolar disturbance and X-linked mental retardation. The mechanism by which NCS-1 would be involved in the causes and/or consequences of these neurodisorders is still far from elucidation. Independent evidence has pointed NCS-1 as a key regulator of synaptic efficacy by altering the expression and activity of voltage-gated channels, inhibiting internalization of dopaminergic receptors, and altering phosphoinositide metabolism. In this study, we examined the possible participation of NCS-1 protein in signal transmission dependent on muscarinic receptor activation, using PC12 cells stably expressing NCS-1 (PC12-NCS-1). Carbachol (CCH; 300 microM) was able to evoke glutamate release more efficiently from PC12-NCS-1 (15.3+/-1.0nmol/mg of protein) than wild type cells (PC12-wt; 8.3+/-0.9nmol/mg of protein). This increase of glutamate release induced by CCH was independent on extracellular Ca2+ influx. Additionally, a larger increase of cytoplasmic levels of InsP3 (663.0+/-63.0 and 310.0+/-39.0% of fluorescence in A.U.) and [Ca2+]i (766.4+/-40.0 and 687.8+/-37.1nmol/L) was observed after CCH stimulus of PC12-NCS-1 compared with PC12-wt. Clearly distinction between intracellular Ca2+ dynamics was also observed in PC12-NCS-1 and PC12-wt. A larger increase followed by fast decay of [Ca2+]i was observed in PC12-NCS-1. A plateau with a delayed decay of [Ca2+]i was characteristic of PC12-wt [Ca2+]i response. Both enhancement of InsP3 production and glutamate release observed in PC12-NCS-1 were blocked by atropine (10 microM). Together, our data show that overexpression of NCS-1 in PC12 cells induces an enhancement of intracellular second messenger and transmitter release dependent on CCH response, suggesting that muscarinic signaling is "up-regulated" in this cell model.
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Ácido Glutámico/metabolismo , Proteínas Sensoras del Calcio Neuronal/fisiología , Neuropéptidos/fisiología , Receptores Muscarínicos/metabolismo , Transducción de Señal/fisiología , Animales , Calcio/metabolismo , Calcio/farmacología , Carbacol/farmacología , Quelantes/farmacología , Agonistas Colinérgicos/farmacología , Ácido Egtácico/análogos & derivados , Ácido Egtácico/farmacología , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Microscopía Fluorescente , Proteínas Sensoras del Calcio Neuronal/genética , Proteínas Sensoras del Calcio Neuronal/metabolismo , Neuropéptidos/genética , Neuropéptidos/metabolismo , Células PC12 , Transporte de Proteínas/efectos de los fármacos , Ratas , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , TransfecciónRESUMEN
BACKGROUND AND AIM: Ototoxicity is a potential adverse effect of chemotherapy with platin drugs, such as cisplatin and carboplatin, in children. Hearing loss (HL) affecting frequencies below 4 kHz can compromise speech perception. The aim of this study was to investigate whether genetic variants previously implicated in ototoxicity are associated with HL overall and HL below 4 kHz in pediatric oncology patients treated with cisplatin or carboplatin. MATERIALS AND METHODS: Patients given cisplatin or carboplatin for a pediatric cancer at least 5 years prior to the start of the study were enrolled. The patients underwent comprehensive audiological evaluations and genotyping to detect the presence of the GJB2 c.35delG, GSTP1 c.313A>G, and MT-RNR1 m.1555A>G polymorphisms. RESULTS: HL was identified in 31/61 patients (50.8%), including 28/42 treated with cisplatin (66.6%) and 3/19 treated with carboplatin (15.8%). HL was associated with higher mean doses of cisplatin (p = .002) and carboplatin (p = .010). The c.313A>G variant of GSTP1 (heterozygous or homozygous) was detected in 31/61 patients (50.8%). An association between this variant allele and HL involving frequencies ≤ 4 kHz was identified (p = .020; 10-fold vs. non-carriers). No associations with HL were observed for GJB2 or MT-RNR1 gene variants. CONCLUSION: The GSTP1 c.313A>G variant may increase the risk of low-frequency HL in pediatric oncology patients treated with cisplatin or carboplatin chemotherapy.
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Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Gutatión-S-Transferasa pi/genética , Pérdida Auditiva/genética , Neoplasias/tratamiento farmacológico , Polimorfismo Genético , Carboplatino/administración & dosificación , Niño , Preescolar , Cisplatino/administración & dosificación , Femenino , Estudios de Seguimiento , Pérdida Auditiva/inducido químicamente , Pérdida Auditiva/patología , Humanos , Masculino , Neoplasias/patología , Pronóstico , Estudios ProspectivosRESUMEN
UNLABELLED: The aim of the study was to evaluate the sensitivity and specificity of TI-201 myocardial perfusion SPECT for the diagnosis of ischaemic cardiopathy in a group of patients with chronotropic insufficiency. MATERIALS AND METHODS: The examinations of 750 patients who had attended for the diagnosis of ischaemic cardiopathy during 2005-2006 were selected. 28 % (n = 209) did not reach submaximal frequency. Data on the diagnosis was collected in 112 by telephone interview. Ergometry and SPECT were carried out following the usual techniques. RESULTS: Patients who reached submaximal frequency and patients with chronotropic insufficiency did not show differences in age and exercise time. The proportion of patients on beta-blocker treatment, with clinically positive ergometries and pathological SPECT was higher in the patient group which had not reached 85 % of their maximum frequency. The data obtained in the patient group which did not reach submaximal frequency and followed-up by telephone interview showed a SPECT sensitivity of 84 % and specificity of 96 %. The sensitivity of the ergometry was 25 % and its specificity was 96 %. CONCLUSIONS: Ergometry with myocardial perfusion SPECT has adequate sensitivity and specificity for the diagnosis of ischaemic cardiopathy, even in patients with chronotropic incompetence. The proportion of pathological examinations is higher in those patients in whom tachycardia could not be sufficiently induced, which seems to indicate that the inability to reach submaximal frequency is related with a higher probability of having ischaemic cardiopathy.
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Tomografía Computarizada por Emisión de Fotón Único Sincronizada Cardíaca , Prueba de Esfuerzo , Isquemia Miocárdica/diagnóstico por imagen , Isquemia Miocárdica/fisiopatología , Imagen de Perfusión Miocárdica , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y Especificidad , Radioisótopos de Talio , Adulto JovenRESUMEN
INTRODUCTION: Exercise-induced left bundle branch block (EI-LBBB) is a rare circumstance of unknown significance. The purpose of this paper is to describe the scintigraphic features and the prognostic value of this finding. MATERIAL AND METHODS: We reviewed the features of 1,885 patients who had visited our department to undergo GATED-SPECT ergometry to diagnose ischaemic heart disease. Seven patients showed EI-LBBB throughout the exercise testing. Coronary angiography was performed in 4 of them. Patients were followed-up over an average period of time of 30±8 months. The onset of major cardiovascular events was recorded during the follow-up period. RESULTS: The prevalence of EI-LBBB was 0.37%. Six out of 7 patients were women. Myocardial function and perfusion were normal in 3 patients. Three patients had fixed perfusion defects and one patient had a reversible defect. Two out of the 4 patients showing perfusion defects presented a moderate-severe decrease of the left ventricular ejection fraction. None of the 4 patients with perfusion defects were found to have coronary disease on coronary angiography. CONCLUSIONS: The prevalence of EI-LBBB among the patients that came to undergo GATED-SPECT ergometry was very low. The finding was more frequent in women. In our series, 2 patients presented non-ischaemic structural heart disease, but no patient was diagnosed with coronary artery disease. In our patients the presence of EI-LBBB did not relate to a greater risk of experiencing a major cardiovascular event.
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Bloqueo de Rama/etiología , Prueba de Esfuerzo/efectos adversos , Anciano , Bloqueo de Rama/diagnóstico por imagen , Bloqueo de Rama/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Imagen de Perfusión Miocárdica , Prevalencia , PronósticoRESUMEN
Cochlear implants can successfully restore hearing in profoundly deaf individuals and enable speech comprehension. However, the acoustic signal provided is severely degraded and, as a result, many important acoustic cues for perceiving emotion in voices and music are unavailable. The deficit of cochlear implant users in auditory emotion processing has been clearly established. Yet, the extent to which this deficit and the specific cues that remain available to cochlear implant users are unknown due to several confounding factors. Here we assessed the recognition of the most basic forms of auditory emotion and aimed to identify which acoustic cues are most relevant to recognize emotions through cochlear implants. To do so, we used stimuli that allowed vocal and musical auditory emotions to be comparatively assessed while controlling for confounding factors. These stimuli were used to evaluate emotion perception in cochlear implant users (Experiment 1) and to investigate emotion perception in natural versus cochlear implant hearing in the same participants with a validated cochlear implant simulation approach (Experiment 2). Our results showed that vocal and musical fear was not accurately recognized by cochlear implant users. Interestingly, both experiments found that timbral acoustic cues (energy and roughness) correlate with participant ratings for both vocal and musical emotion bursts in the cochlear implant simulation condition. This suggests that specific attention should be given to these cues in the design of cochlear implant processors and rehabilitation protocols (especially energy, and roughness). For instance, music-based interventions focused on timbre could improve emotion perception and regulation, and thus improve social functioning, in children with cochlear implants during development.
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Percepción Auditiva , Implantación Coclear/instrumentación , Implantes Cocleares , Señales (Psicología) , Emociones , Música , Personas con Deficiencia Auditiva/rehabilitación , Calidad de la Voz , Estimulación Acústica , Adulto , Estimulación Eléctrica , Femenino , Humanos , Juicio , Masculino , Persona de Mediana Edad , Personas con Deficiencia Auditiva/psicología , Adulto JovenRESUMEN
Oligodendrocytes, the myelinating cells of CNS axons, are highly vulnerable to excitotoxic signals mediated by glutamate receptors of the AMPA and kainate classes. Receptors in these cells are commonly activated by glutamate that is released from axons and glial cells. In addition, oligodendrocytes contribute to the control of extracellular glutamate levels by means of their own transporters. However, acute and chronic alterations in glutamate homeostasis can result in overactivation of AMPA and kainate receptors and subsequent excitotoxic oligodendroglial death. Furthermore, demyelinating lesions caused by excitotoxins can be similar to those observed in multiple sclerosis. This, together with the effect of AMPA and kainate receptor antagonists in ameliorating the neurological score of animals with experimental autoimmune encephalomyelitis (an animal model of multiple sclerosis), indicates that oligodendrocyte excitotoxicity could be involved in the pathogenesis of demyelinating disorders.
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Autoinmunidad/fisiología , Enfermedades Desmielinizantes/metabolismo , Ácido Glutámico/metabolismo , Esclerosis Múltiple/metabolismo , Neurotoxinas/metabolismo , Oligodendroglía/metabolismo , Animales , Autoinmunidad/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Muerte Celular/fisiología , Enfermedades Desmielinizantes/tratamiento farmacológico , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Encefalomielitis Autoinmune Experimental/metabolismo , Encefalomielitis Autoinmune Experimental/patología , Humanos , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple/patología , Neurotoxinas/antagonistas & inhibidores , Oligodendroglía/efectos de los fármacos , Nervio Óptico/efectos de los fármacos , Nervio Óptico/patología , Receptores AMPA/antagonistas & inhibidores , Receptores AMPA/metabolismo , Receptores de Ácido Kaínico/antagonistas & inhibidores , Receptores de Ácido Kaínico/metabolismo , Receptor de Ácido Kaínico GluK2RESUMEN
OBJECTIVES: We sought to evaluate whether pravastatin treatment increases myocardial perfusion, as assessed by thallium-201 single-photon emission computed tomographic (SPECT) dipyridamole testing, in patients with coronary artery disease (CAD) and average cholesterol levels. BACKGROUND: Previous studies in hypercholesterolemic patients have demonstrated that cholesterol reduction restores peripheral and coronary endothelium-dependent vasodilation and increases myocardial perfusion. METHODS: This was a randomized, placebo-controlled study with a cross-over design. Twenty patients with CAD were randomly assigned to receive 20 mg of pravastatin or placebo for 16 weeks and then were crossed over to the opposite medication for a further 16 weeks. Lipid and lipoprotein analysis and dipyridamole thallium-201 SPECT were performed at the end of each period. The SPECT images were visually analyzed in eight myocardial segments using a 4-point scoring system by two independent observers. A summed stress score and a summed rest score were obtained for each patient. Quantitative evaluation was performed by the Cedars-Sinai method. The magnitude of the defect was expressed as a percentage of global myocardial perfusion. RESULTS: Total and low density lipoprotein cholesterol levels during placebo were 214 +/- 29 mg/dl and 148 +/- 25 mg/dl, respectively. These levels with pravastatin were 170 +/- 23 mg/dl and 103 +/- 23 mg/dl, respectively. The summed stress score and summed rest score were lower with pravastatin than with placebo (7.2 +/- 2.3 vs. 5.9 +/- 2.3, p = 0.012 and 3.2 +/- 1.6 vs. 2.4 +/- 2.2, p = 0.043, respectively). Quantitative analysis showed a smaller perfusion defect with pravastatin (29.2%) as compared with placebo (33.8%) (p = 0.021) during dipyridamole stress. No differences were found at rest. CONCLUSIONS: Reducing cholesterol levels with pravastatin in patients with CAD improves myocardial perfusion during dipyridamole stress thallium-201 SPECT.
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Colesterol/sangre , Circulación Coronaria/efectos de los fármacos , Enfermedad Coronaria/tratamiento farmacológico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Pravastatina/administración & dosificación , Anciano , LDL-Colesterol/sangre , Circulación Coronaria/fisiología , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/fisiopatología , Estudios Cruzados , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/fisiopatología , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Pravastatina/efectos adversos , Tomografía Computarizada de Emisión de Fotón Único , Resultado del Tratamiento , Vasodilatación/efectos de los fármacos , Vasodilatación/fisiologíaRESUMEN
The reactivity of different heteroscorpionate ligands based on bis(pyrazol-1-yl)methane, with different iridium-(i) and -(iii) precursors is reported. The reaction of the heteroscorpionate lithium salts "Li(bdmpza)", [bdmpza = bis(3,5-dimethylpyrazol-1-yl)acetate], "Li(bdmpzdta)" [bdmpzdta = bis(3,5-dimethylpyrazol-1-yl)dithioacetate] and "Li(S)-mbpam" [(S)-mbpam = (S)-(-)-N-α-methylbenzyl-2,2-bis(3,5-dimethylpyrazol-1-yl)acetamidate] with 1 equivalent of [IrCl3(THF)3] in THF for 18 h affords high yields of neutral and anionic heteroscorpionate chloride iridium complexes [IrCl2(bdmpza)(THF)] (), [Li(THF)4][IrCl3(bdmpzdta)] () and [IrCl2{(S)-mbpam})(THF)] (). Solution of complex in acetonitrile at room temperature leads to complex [IrCl2{(S)-mbpam})(NCCH3)] (). Complexes and were isolated as enantiopure compounds. The reaction of the lithium salt "Li(bdmpza)" with [IrCl(η(4)-CH2[double bond, length as m-dash]C(Me)C(Me)[double bond, length as m-dash]CH2)]2 in THF for 18 h gave the Ir(i) complex [Ir(bdmpza)(η(4)-CH2[double bond, length as m-dash]C(Me)C(Me)[double bond, length as m-dash]CH2)] (). The reaction of complex with CO (2 atm) at room temperature leads to a new complex of Ir(iii), [Ir(bdmpza)(k(2)-CH2C(Me)[double bond, length as m-dash]C(Me)CH2)(CO)] (). Treatment of heteroscorpionate ligand precursors "Li(bdmpza)" and "Li(bdmpzdta)" with [IrCp*Cl2]2 in THF yielded the iridium(iii) complexes [Ir2Cp*2Cl2(bdmpzx)] (x = a , x = dta ). These complexes have helical chirality due to the demands of the fixed pyrazole rings. The stereoisomerism and the self-assembly processes of these helicates have been studied in some detail in solution by NMR spectroscopy and in the solid state by X-ray diffraction. Mixtures of M- and P-handed enantiomers were obtained. Complex undergoes a decarboxylation process initiated by the HCl generated in the previous step leading to the known ionic complex [IrClCp*(bdmpm)][IrCl3Cp*] [bdmpm = bis(3,5-dimethylpyrazol-1-yl)methane] (). The structures of the complexes were determined by spectroscopic methods and the X-ray crystal structures of , , and were also established.
RESUMEN
BACKGROUND AND PURPOSE: Spinal voltage-gated calcium channels (VGCCs) are pivotal regulators of painful and inflammatory alterations, representing attractive therapeutic targets. We examined the effects of epidural administration of the P/Q- and N-type VGCC blockers Tx3-3 and Phα1ß, respectively, isolated from the spider Phoneutria nigriventer, on symptomatic, inflammatory and functional changes allied to mouse cyclophosphamide (CPA)-induced haemorrhagic cystitis (HC). The effects of P. nigriventer-derived toxins were compared with those displayed by MVIIC and MVIIA, extracted from the cone snail Conus magus. EXPERIMENTAL APPROACH: HC was induced by a single i.p. injection of CPA (300 mg·kg(-1) ). Dose- and time-related effects of spinally administered P/Q and N-type VGCC blockers were assessed on nociceptive behaviour and macroscopic inflammation elicited by CPA. The effects of toxins were also evaluated on cell migration, cytokine production, oxidative stress, functional cystometry alterations and TRPV1, TRPA1 and NK1 receptor mRNA expression. KEY RESULTS: The spinal blockage of P/Q-type VGCC by Tx3-3 and MVIIC or N-type VGCC by Phα1ß attenuated nociceptive and inflammatory events associated with HC, including bladder oxidative stress and cytokine production. CPA produced a slight increase in bladder TRPV1 and TRPA1 mRNA expression, which was reversed by all the toxins tested. Noteworthy, Phα1ß strongly prevented bladder neutrophil migration, besides HC-related functional alterations, and its effects were potentiated by co-injecting the selective NK1 receptor antagonist CP-96345. CONCLUSIONS AND IMPLICATIONS: Our results shed new light on the role of spinal P/Q and N-type VGCC in bladder dysfunctions, pointing out Phα1ß as a promising alternative for treating complications associated with CPA-induced HC.
Asunto(s)
Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio Tipo N/metabolismo , Cistitis/tratamiento farmacológico , Hemorragia/tratamiento farmacológico , Neuropéptidos/farmacología , Venenos de Araña/farmacología , Animales , Bloqueadores de los Canales de Calcio/administración & dosificación , Bloqueadores de los Canales de Calcio/aislamiento & purificación , Ciclofosfamida/administración & dosificación , Cistitis/inducido químicamente , Masculino , Ratones , Neuropéptidos/administración & dosificación , Neuropéptidos/aislamiento & purificación , Venenos de Araña/administración & dosificación , Venenos de Araña/aislamiento & purificación , Médula Espinal/efectos de los fármacosRESUMEN
O objetivo deste estudo foi avaliar o efeito da ω-conotoxina MVIIC e das células-tronco mesenquimais (CTM) de forma isolada e sua associação nos ratos submetidos ao trauma medular agudo (TMA). Trinta Rattus novergicus, linhagem Wistar, três meses de idade, foram distribuídos igualmente em cinco grupos experimentais: controle negativo (CN), controle positivo (CP), ω-conotoxina MVIIC (MVIIC), células-tronco mesenquimais da medula óssea (CTM-MO) e associação (MVIIC + CTM-MO). O grupo CN foi submetido à laminectomia sem trauma medular, e os grupos CP, MVIIC, CTM-MO e MVIIC + CTM-MO foram submetidos ao trauma medular contusivo. O grupo CP recebeu, uma hora após o TMA, 10µL de PBS estéril, e os grupos MVIIC e MVIIC + CTM-MO receberam 10µL de PBS contendo 20pmol da ω-conotoxina MVIIC, todos por via intratecal. Os grupos CTM-MO e MVIIC + CTM-MO receberam, 24 horas após, 1x106 de CTM via intravenosa. Avaliou-se a recuperação da função locomotora até o sétimo dia pós-trauma. Os animais tratados com MVIIC + CTM-MO obtiveram recuperação motora após o trauma medular agudo (P<0,05). Conclui-se que essa associação apresentou efeito neuroprotetor com melhora na função locomotora em ratos Wistar.(AU)
The objective of this study was to evaluate the effect of isolated ω-conotoxin MVIIC and mesenchymal stem cells (MSCs) and its association in rats submitted to acute spinal cord injury (SCI). Thirty Rattus norvegicus, Wistar strain, three-month-old rats were randomly distributed in five experimental groups with six animals: negative control (CN), positive control (CP), ω-conotoxin MVIIC (MVIIC), bone marrow mesenchymal stem cells (CTM-MO) and the association (MVIIC + CTM-MO). The CN group underwent laminectomy without spinal cord trauma, and groups CP, MVIIC, CTM-MO and MVIIC + CTM-MO were submitted to contusive spinal cord trauma. The CP group received 10µl of PBS one hour after SCI, and groups MVIIC and MVIIC + CTM-MO received 10µl of PBS containing 20pmol of ω-conotoxin MVIIC, both intrathecally. Groups CTM-MO and MVIIC + CTM-MO received 1x106 of MSCs intravenously 24 hours later. The recovery of locomotor function was evaluated up to seven days post-injury. The animals treated with MVIIC + CTM-MO obtained motor recovery after SCI (P<0.05). It is concluded that this association showed neuroprotective effect with improvements in locomotor function in Wistar rats.(AU)