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Solar batteries capable of harvesting sunlight and storing solar energy present an attractive vista to transition our energy infrastructure into a sustainable future. Here we present an integrated, fully earth-abundant solar battery based on a bifunctional (light absorbing and charge storing) carbon nitride (K-PHI) photoanode, combined with organic hole transfer and storage materials. An internal ladder-type hole transfer cascade via a transport layer is used to selectively shuttle the photogenerated holes to the PEDOT:PSS cathode. This concept differs from previous designs such as light-assisted battery schemes or photocapacitors and allows charging with light during both electrical charge and discharge, thus substantially increasing the energy output of the cell. Compared to battery operation in the dark, light-assisted (dis)charging increases charge output by 243%, thereby increasing the electric coulombic efficiency from 68.3% in the dark to 231%, leading to energy improvements of 94.1% under illumination. This concept opens new vistas towards compact, highly integrated devices based on multifunctional, carbon-based electrodes and separators, and paves the way to a new generation of earth-abundant solar batteries.
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The use of electrokinetic Fenton (EK Fenton) process, as promising soil remediation approach, was investigated by using an iron electrode with different supporting electrolytes (tap water, H2O2, and citric acid) to depollute soil spiked with petroleum where kaolin was selected as low hydraulic conductivity. The results clearly confirm that, the combination of electrokinetic remediation (EK) and Fenton technologies, is an efficient oxidizing approach for removing hydrocarbons from this kind of soil. In fact, the electrokinetic Fenton reactions and the control of the soil pH conditions by adding citric acid enhanced the oxidation process because the addition of the H2O2 with iron electrode resulted in higher removal efficiencies (89%) for total petroleum hydrocarbons (TPHs). These figures allowed to confirm that EK Fenton process with pH control contributed for the transport of H2O2 and Fe2+ ions in the soil by electromigration and eletro-osmotic phenomena. Conversely, no control of pH conditions when only EK was applied, achieved lower hydrocarbons removal (27%) after 15 d of treatment due to the precipitation of iron ions. Finally, the efficiency of the EK Fenton remediation prevented the generation of secondary effluent with higher organic content, avoiding its treatment by other advanced oxidation process.
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Recuperação e Remediação Ambiental/métodos , Poluição por Petróleo , Poluentes do Solo/química , Ácido Cítrico/química , Técnicas Eletroquímicas/instrumentação , Eletrodos , Recuperação e Remediação Ambiental/instrumentação , Hidrocarbonetos/química , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Ferro/química , Caulim/química , Osmose , Oxirredução , Solo/químicaRESUMO
The Human Variome Project (HVP) is an international effort aiming systematically to collect and share information on all human genetic variants. It has been working for years in collaboration with local scientific societies by establishing systems to collect every genetic variant reported in a country and to store these variants within a database repository: LOVD (Argentinian chapter: ar.lovd.org). Formally established in 2017 in the Argentinian Node, up to June 2019 we collected more than 25,000 genetic variants deposited by 17 different laboratories. Nowadays the HVP country nodes represent more than 30 countries. In Latin America there are four country nodes: Argentina, Brazil, Mexico and Venezuela; the first two interacted recently launching the LatinGen database. In the present work we want to share our experience in applying the HVP project focusing on its organization, rules and nomenclature to reach the goal of sharing genetic variants and depositing them in the Leiden Open Variation Database. Contributing laboratories are seeking to share variant data to gain access all over the country. It is one of our goals to stimulate the highest quality by organizing courses, applying current nomenclature rules, sponsoring lectures in national congresses, distributing newsletter to serve the Argentinian genomics community and to stimulate the interaction among Latin America countries.
El Proyecto Varioma Humano (HVP) es un esfuerzo internacional que tiene como objetivo recopilar y compartir sistemáticamente información sobre todas las variantes genéticas humanas. Hemos estado trabajando durante tres años en colaboración con sociedades científicas locales, mediante el establecimiento de sistemas para recolectar todas las variantes genéticas reportadas en el país y almacenarlas dentro de la base de datos LOVD (capítulo argentino: ar.lovd.org). En el año 2017 fue establecido formalmente el Nodo Argentino del HVP, habiéndose recolectado más de 25.000 variantes genéticas depositadas por 17 laboratorios diferentes hasta junio de 2019. Hoy en día existen al menos 30 nodos del HVP, correspondientes a diferentes países. En América Latina hay cuatro nodos: Argentina, Brasil, México y Venezuela; Los dos primeros interactuaron recientemente lanzando la base de datos LatinGen. En el presente trabajo queremos compartir nuestra experiencia en la aplicación del proyecto HVP centrándonos en su organización, reglas y nomenclatura para alcanzar el objetivo de compartir variantes genéticas y depositarlas en la base de datos de variaciones abiertas de Leiden (LOVD). Es uno de nuestros objetivos estimular la más alta calidad mediante la organización de cursos, aplicación de las reglas de nomenclatura actuales, patrocinio de conferencias en congresos nacionales, distribución de boletines informativos para la comunidad de genómica argentina, y estimulación de la interacción entre los países de América Latina.
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Objectives: Studies showed that the recovery of patients with Unresponsive Wakefulness Syndrome (UWS) is also correlated to the recovery of circadian rhythms. In this study, we observed the correlations between patients with UWS biometrical and ambient parameters. Methods: A dedicated monitoring system was realized to record and correlate the level of noise and luminosity with biometric Heart Rate (HR), Heart Rate Variability (HRV) and Breath Rate (BR) parameters. Eleven patients with UWS were recruited and monitored for 13 ± 7 days. Correlation of ambient and biometric parameters was analyzed by Spearman's test. Wilcoxon's test was used to compare the biometric parameters in two different moments of daily activity in the rehabilitation unit (night and day). Patients showed a moderate negative or positive correlation between biometric and ambient parameters. Results: Significant differences between night and morning (0.0001 < p ≤ 0.001) were found for HR, HRV and BR in seven, five and four patients, respectively, at Wilcoxon's test. HR and BR were higher during the night while HRV was lower. Conclusion: In patients with UWS, lower HRV and higher HR and BR during the night might be indicative of interference in sleep/wake cycles. The modifications of the environment surrounding the patient due to the unit procedures of the staff and/or some interaction modalities of the relatives may have an effect on residual endogenous mechanisms of self-regulation. However, differences between night and day in the biometrical parameters are not necessarily linked to the changes in the environment care unit.
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Sistema Nervoso Autônomo/fisiopatologia , Transtornos da Consciência/fisiopatologia , Meio Ambiente , Hospitalização , Adulto , Idoso , Idoso de 80 Anos ou mais , Eletrocardiografia , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Taxa Respiratória , Síndrome , Vigília , Adulto JovemRESUMO
BACKGROUND: Occupational self-analysis programmes have been developed to promote health, mainly in older adults. However, we have found no published studies dealing with this in people with intellectual disability (ID). The aim of this study was to examine the effectiveness of an occupational self-analysis programme in people with ID, focusing on the areas of subjective health perception and participation. METHODS: This study explored the benefits of the 'Occupational Self-Analysis Programme' in people with ID. The intervention group comprised 12 participants and the control group comprised 13 participants. Outcomes were measured using the SF-36 Health Survey and the Role Checklist. The contents of participants' journals and a focus group discussion were also analysed. RESULTS: Compared with the control group, the intervention group showed statistically significant improvements in role limitations because of physical health and role limitations because of emotional problems, social functioning and the cumulative scores of the mental component in the SF-36 Health Survey. The qualitative analysis revealed that participants in the intervention group increased their participation in activities related with daily living, leisure, employment seeking and acquisition, and social participation. These participants also became more aware of issues that lead to a greater engagement in meaningful occupations. CONCLUSION: This programme allowed participants to engage in meaningful activities with other people and to increase their perceived health status by raising awareness of the strengths and difficulties of participation.
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Atividades Cotidianas , Emprego , Promoção da Saúde , Deficiência Intelectual/reabilitação , Atividades de Lazer , Terapia Ocupacional/métodos , Avaliação de Processos e Resultados em Cuidados de Saúde , Participação Social , Adolescente , Adulto , Feminino , Humanos , Masculino , Terapia Ocupacional/instrumentação , Projetos Piloto , Avaliação de Programas e Projetos de Saúde , Pesquisa Qualitativa , Adulto JovemRESUMO
RESUMEN: El correcto sellado apical es un paso importante durante el tratamiento de conductos, para esto, se utilizan puntas de gutapercha y cemento sellador, de este último existen diversas formulaciones químicas en el mercado, por lo cual es importante tomar en cuenta los efectos que estas pueden tener en el proceso de cicatrización periapical. El propósito de este estudio fue evaluar la biocompatibilidad de cuatro cementos selladores con diferente composición química con osteoblastos humanos. Se prepararon extractos de cementos selladores a con dos concentraciones (10 mg/mL y 40 mg/mL) y dos tiempos de exposición (10 min y 8 h), estos fueron colocados en contacto con osteoblastos humanos para evaluar la proliferación y citotoxicidad a 24, 72 y 96 h con sus respectivos controles y blancos. Se realizó un análisis estadístico con ANOVA de un factor y la prueba de comparaciones múltiple de Bonferroni. Los resultados obtenidos, tanto en el ensayo de citotoxicidad como en el de proliferación, indicaron que el cemento a base de resina no es biocompatible con osteoblastos. El cemento a base de poli-dimetilxilosano fue el único que no mostró citotoxicidad a ningún de tiempo de exposición y concentración examinadas en este estudio.
ABSTRACT: Correct apical sealing is an important step during root canal treatment, hence, gutta-percha points and sealant are used. There are several chemical compositions on the market, so it is important to evaluate the effects of these in the periapical healing process. The aim of this study was to evaluate the biocompatibility of four sealer cements with different chemical composition placed in contact with human osteoblast. Different extracts were prepared at two concentrations (10 mg/mL and 40 mg/mL) and two exposure times (10 min and 8 h) these were placed in contact with human osteoblast to evaluate cytotoxicity and proliferation at 24, 48 and 72 h with their respective controls and blanks. A statistical analysis was performed with ANOVA of one factor and Bonferroni post hoc. Results obtained in cytotoxicity and proliferation assays, indicated that the resinbased cement is not biocompatible with osteoblast. The poly-dimethylxilosanbased cement was the only that did not show cytotoxicity at any time of exposure and concentration examined in this study.
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Humanos , Osteoblastos , Teste de Materiais/métodos , Cimentos Dentários/química , Técnicas In Vitro , Análise de VariânciaRESUMO
A Regional Metrology Organization (RMO) Key Comparison of dew/frost point temperatures over the range -30 °C TO +20 °C was carried out by the National Institute of Standards and Technology (NIST, USA) and the Laboratorio Costarricense de Metrología (LACOMET, Costa Rica), between February 2015 and August 2015. The results of this comparison are reported here, along with descriptions of the humidity laboratory standards for NIST and LACOMET and the uncertainty budget for these standards. This report also describes the protocol for the comparison and presents the data acquired. The results are analyzed, determining the degree of equivalence between the dew/frost-point standards of NIST and LACOMET.
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In this Perspective we discuss the implications of employing metal particles of different shape, size, and composition as absorption enhancers in methylammonium lead iodide perovskite solar cells, with the aim of establishing some guidelines for the future development of plasmonic resonance-based photovoltaic devices. Hybrid perovskites present an extraordinarily high absorption coefficient which, as we show here, makes it difficult to extrapolate concepts and designs that are applied to other solution-processed photovoltaic materials. In addition, the variability of the optical constants attained from perovskite films of seemingly similar composition further complicates the analysis. We demonstrate that, by means of rigorous design, it is possible to provide a realistic prediction of the magnitude of the absorption enhancement that can be reached for perovskite films embedding metal particles. On the basis of this, we foresee that localized surface plasmon effects will provide a means to attain highly efficient perovskite solar cells using films that are thinner than those usually employed, hence facilitating collection of photocarriers and significantly reducing the amount of potentially toxic lead present in the device.
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OBJECTIVES: To monitor repair of bone erosions using magnetic resonance imaging (MRI) in patients with rheumatoid arthritis (RA) during etanercept combination therapy. METHOD: The study population comprised 29 RA patients [biologic-naïve, 28-joint Disease Activity Score (DAS28) ≥ 3.2] starting etanercept combination therapy with disease-modifying anti-rheumatic drugs (DMARDs) and completing the 1-year study period with the same treatment. Clinical and laboratory assessments and MRI of the hand were performed at baseline and at 1 year. MRI findings were scored by two readers using the Rheumatoid Arthritis MRI Scoring System (RAMRIS). Both readers were blind to the chronological order of the MRI scans, the identity of the patients, and clinical and other imaging data. Tenosynovitis was also scored. The intra- and inter-reader intraclass correlation coefficients (ICCs) were calculated, along with the sensitivity to change with the smallest detectable difference (SDD). Repair of erosions was defined as a RAMRIS score of at least 1 point lower than baseline. RESULTS: The mean RAMRIS score for erosions did not change but all other inflammatory MRI parameters decreased significantly. In 19 patients, the RAMRIS score for erosions remained unchanged after 1 year. In five patients the score decreased after 1 year, although the decrease exceeded the SDD in only one patient (3.4%). CONCLUSIONS: Etanercept combined with DMARDs stopped the progression of erosions, as measured by the RAMRIS, in 82.8% of our RA patients and occasional repair of bone erosions occurred after 1 year of treatment.
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Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/patologia , Osso e Ossos/patologia , Imunoglobulina G/uso terapêutico , Receptores do Fator de Necrose Tumoral/uso terapêutico , Adulto , Progressão da Doença , Quimioterapia Combinada , Etanercepte , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Tenossinovite/patologia , Resultado do TratamentoAssuntos
Cinamatos/efeitos adversos , Dermatite Fotoalérgica/etiologia , Protetores Solares/efeitos adversos , Adulto , Cinamatos/administração & dosagem , Dermatite Fotoalérgica/tratamento farmacológico , Dermatite Fotoalérgica/imunologia , Feminino , Humanos , Hidrocortisona/administração & dosagem , Prednisona/administração & dosagem , Protetores Solares/administração & dosagemRESUMO
REASONS FOR PERFORMING STUDY: Standing surgical procedures are performed commonly in horses under sedation. This approach minimises the morbidity/mortality risks associated with general anaesthesia. The use of a medetomidine and morphine combination has not been investigated in horses despite the usefulness of each drug individually. OBJECTIVE: To determine the efficacy of a medetomidine and morphine combination to produce standing sedation with minimal cardiorespiratory changes and adequate analgesia for exploratory laparascopy in mature horses. HYPOTHESIS: The combination of medetomidine and morphine will induce reliable sedation with minimal cardiorespiratory changes. METHODS: Medetomidine (5 microg/kg bwt i.v.) followed in 10 min by morphine (50 microg/kg bwt i.v.) and 10 min later by a constant rate infusion (CRI) of medetomidine and morphine (5 and 30 microg/kg bwt/h, respectively) was administered in 7 horses undergoing standing exploratory laparoscopy. Quality of sedation and cardiorespiratory function were assessed. RESULTS: Sedation was satisfactory after the medetomidine and morphine bolus. The CRI of both drugs enhanced sedation and ataxia. Mean visual analogue scores on a scale of 10 varied between 7.8 and 8.8 and were similar between anaesthesiologists and surgeons. Heart rate, respiratory rate and packed cell volume (PCV) decreased significantly after medetomidine and, at some periods, during the CRI. Blood pressure only increased significantly at 5 min and arterial O2 decreased significantly at 10 min post medetomidine. PCV remained significantly lower and total protein decreased post morphine and CRI administration. Arterial CO2 increased towards the end of the CRI. Cardiac output did not change significantly over time. CONCLUSION AND CLINICAL RELEVANCE: The combination of medetomidine and morphine results in reliable sedation and stable cardiorespiratory function in horses undergoing exploratory laparascopy.
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Cavalos/fisiologia , Laparoscopia/veterinária , Medetomidina/administração & dosagem , Morfina/administração & dosagem , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/efeitos adversos , Animais , Gasometria/veterinária , Pressão Sanguínea/efeitos dos fármacos , Quimioterapia Combinada , Feminino , Frequência Cardíaca/efeitos dos fármacos , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/efeitos adversos , Infusões Intravenosas/veterinária , Laparoscopia/métodos , Masculino , Medetomidina/efeitos adversos , Morfina/efeitos adversos , Respiração/efeitos dos fármacosRESUMO
This paper discusses H(2)S, NH(3) and VOCs removal by sewage-sludge-derived materials with outstanding chemical and textural properties. These materials were obtained from different precursors using different chemical and thermal treatments. Results show that the H(2)S removal process entailed a catalytic conversion of H(2)S to S or SO(4) (2-) species. On the other hand, adsorption is the main mechanism governing the performance of sludge-based materials for NH(3) and VOCs. Retention capacities (x/M values) obtained for some of the sludge-based adsorbents/catalysts are similar to those obtained with commercial activated carbons selected as reference materials.
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Amônia/isolamento & purificação , Sulfeto de Hidrogênio/isolamento & purificação , Odorantes , Esgotos/química , Compostos Orgânicos Voláteis/isolamento & purificação , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Adsorção , CatáliseRESUMO
BACKGROUND: Neurogenic muscle weakness, ataxia and retinitis pigmentosa (NARP) syndrome have been associated to m.8993T>G/C mutations in the subunit 6 of the ATP synthase (p.MT-ATP6). METHODS: We have performed a mutational screening of the mitochondrial DNA gene encoding for this protein in 62 patients with the disease, that do not carry any of the common mutations described to date. RESULTS: We report clinical and molecular data in one patient who harbours a de novo insertion in the MT-ATP6 gene that results in a truncated subunit. The mutation was heteroplasmic (85%) in muscle DNA and the BN-PAGE analysis showed a clear decrease in the amount of ATP synthase. CONCLUSION: Molecular analysis of NARP patients cannot be limited to the search of the m.8993T>G/C and either the ATP6 or the whole mtDNA should be sequenced.
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Ataxia/genética , DNA Mitocondrial/genética , ATPases Mitocondriais Próton-Translocadoras/genética , Debilidade Muscular/genética , Retinose Pigmentar/genética , Adulto , Sequência de Aminoácidos , Sequência de Bases , Encéfalo/patologia , Humanos , Masculino , Dados de Sequência Molecular , Mutação Puntual , Análise de Sequência , SíndromeRESUMO
El ultrasonido es una técnica de imagen sencilla, no invasiva y accesible que permite la evaluación del sistema musculoesquelético en tiempo real, con la ventaja de examinar las articulaciones en forma dinámica; adicionalmente, con la ayuda del Doppler de poder y de color, se pueden evaluar los fenómenos inflamatorios locales, sin someter al paciente a radiación ionizante. Tiene como desventaja ser dependiente del operador, el cual debe tener un amplio conocimiento de los principios físicos del ultrasonido, estar familiarizado con la ecotextura de los tejidos y de la anatomía musculoesquelética. Además es importante que sepa reconocer los fenómenos sonográficos que pueden presentarse como confusores, denominados artefactos. Este cúmulo de conocimientos es deseable para el especialista en padecimientos musculoesqueléticos, para que pueda interpretar adecuadamente los estudios ecográficos, reconocer los artefactos y así evitar diagnósticos erróneos y procedimientos innecesarios. En una serie de tres artículos se analizan los principios físicos básicos de la ecografía, la sonoanatomía del sistema musculoesquelético y los artefactos más comunes encontrados en ecografía. En esta primera entrega analizaremos los principios físicos básicos involucrados en la producción de imágenes ecográficas.
Ultrasonography is a simple, non invasive and accessible imaging technique that allows the evaluation of a variety of musculoskeletal structures in real time. It has the advantage of dynamic assessment of joints, tendons and muscles; furthermore, the presence of an underlying inflammatory phenomenon can be evaluated with power or color Doppler techniques in the same session without radiation exposure. However, it is an operator dependant technique that needs a in-depth knowledge of basic principles of ultrasound, musculoskeletal anatomy and ecostructure. Additionally, it is important to identify and recognize the presence of ultrasound artifacts that can be image confusors. A basic knowledge of ultrasound physics, as well as, sonoanatomy and ultrasound artifacts recognition is essential to understand ultrasound images. This knowledge diminishes the possibilities of misdiagnoses and unnecessary procedures. In a series of three papers, we will analyze the basic principles of ultrasound, musculoskeletal sonoanatomy and finally ultrasonographic artifacts. In the present paper we review the basic physical and technical principles behind ultrasound images.
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Humanos , Músculo Esquelético , Física , Ultrassom , Ultrassonografia , Aumento da Imagem , Variações Dependentes do Observador , Transdutores , Ultrassonografia DopplerRESUMO
El ultrasonido musculoesquelético se ha convertido en una herramienta útil y eficaz en el diagnóstico de diferentes patologías que afectan el sistema musculoesquelético. Al ser un medio que permite visualizar estructuras tales como tendones, ligamentos, músculos, entre otras, el médico dedicado a este estudio debe tener un conocimiento profundo de la anatomía del sistema musculosquelético. La correcta visualización de estas estructuras y el diagnóstico acertado dependen también de que el operador conozca las imágenes sonográficas propias de cada estructura. En este artículo describimos las características sonográficas normales de las estructuras anatómicas que pueden ser evaluadas por ultrasonido.
Musculoskeletal ultrasound has become a useful and effective tool in the diagnosis of different pathologies that affect the musculoskeletal system. This method allows the visualization of soft tissue structures such as tendons, ligaments, muscles, among others. The healthcare professional dedicated to this area must have a deep knowledge of the anatomy of the musculoskeletal system. The correct visualization of these structures and the correct diagnosis also depend on the operators knowledge of the normal sonographic images of each structure. In this paper we describe the normal sonographic characteristics of the locomotor system that can be evaluated by ultrasound.
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Humanos , Músculo Esquelético , Ultrassonografia , Doenças MusculoesqueléticasRESUMO
El ultrasonido musculoesquelético es susceptible de presentar defectos en su técnica operativa. Estos defectos son llamados artefactos. En este artículo revisaremos los artefactos que comúnmente ocurren en la práctica de este método diagnóstico. El conocimiento de los artefactos y su detección oportuna ayudan al operador a optimizar la práctica diaria del ultrasonido.
The musculoskeletal ultrasound is susceptible to present defects in its operative technique. These defects are called artifacts. In this article we will review the artifacts more susceptible to be found in daily practice. The knowledge of artifacts and their timely detection will help the operator to perform this technique accurately.
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Humanos , Artefatos , Músculo Esquelético , UltrassonografiaRESUMO
BACKGROUND AND PURPOSE: Many in vitro and fewer in vivo studies have shown that tetracyclines present anti-inflammatory activity. We investigated if a novel non-antibacterial, non-chelating hydroxypyrazoline derivative of minocycline, 12S-hydroxy-1,12-pyrazolinominocycline (PMIN), also induced antinociceptive and anti-inflammatory effects. EXPERIMENTAL APPROACH: Antibacterial effects against a minocycline-sensitive Staphylococcus aureus strain were evaluated by applying a cylinder-plate agar diffusion technique. Antibacterial effects of diluted serum from mice pre-treated with minocycline or PMIN were also evaluated. Ca2+ binding activity was assessed by spectrophotometry. Formalin-induced nociceptive responses and carrageenan-induced paw oedema were evaluated in mice. The rota-rod apparatus was used to evaluate motor coordination. KEY RESULTS: Minocycline, but not PMIN, inhibited bacterial growth. Serum from mice treated with minocycline, but not with PMIN, also induced such an effect. The UV absorption spectrum of solutions of minocycline, but not those of PMIN, was markedly changed in the presence of Ca2+. Minocycline or PMIN inhibited both phases of formalin-induced nociception and carrageenan-induced paw oedema. It is unlikely that antinociception resulted from lack of motor coordination, as tetracycline did not impair the performance of mice on the rotating rod. CONCLUSIONS AND IMPLICATIONS: These results indicate that inhibition of nociception and oedema by tetracyclines is neither necessarily linked to antibacterial nor to Ca2+ chelating activities. This study supports the evaluation of the potential usefulness of PMIN in the treatment of painful and inflammatory diseases, as its lack of antibacterial and Ca2+ chelating activities might confer greater safety over conventional tetracyclines.
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Anti-Inflamatórios não Esteroides/uso terapêutico , Edema/tratamento farmacológico , Minociclina/uso terapêutico , Dor/tratamento farmacológico , Pirazóis/uso terapêutico , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Cálcio/metabolismo , Cátions Bivalentes/metabolismo , Quelantes/química , Quelantes/farmacologia , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Minociclina/química , Minociclina/farmacologia , Estrutura Molecular , Atividade Motora/efeitos dos fármacos , Medição da Dor , Pirazóis/química , Pirazóis/farmacologia , Teste de Desempenho do Rota-Rod , Staphylococcus aureus/efeitos dos fármacosRESUMO
AIM: The diseases of the oxidative phosphorylation system consist of a group of disorders originated by a deficient synthesis of adenosine triphosphate (ATP). These diseases are increasingly being diagnosed among patients with multisystemic disorders. Mitochondrial deoxyribonucleic acid (mtDNA) mutations are usually maternally inherited, but they also can be sporadic or secondary to nuclear mutations, that are inherited in a Mendelian mode, or due to environmental hazards. In this review we will update, from a genetic point of view, the knowledge on human mitochondrial diseases, remarking the difficulties to study these pathologies. DEVELOPMENT: To mirror these difficulties, we will use selected examples of mutations in the mitochondrial genome, and review recent advances on mitochondrial pathology due to mutations in the nuclear genes codifying for mitochondrial proteins that participate in a good performance of the oxidative phosphorylation system. CONCLUSIONS: Sequencing of the complete human mtDNA should be part of the basic profile in the study of mitochondrial diseases. Due to the increasing number of nuclear genes involved in the oxidative phosphorylation system performance, their analysis should be based on solid biochemical clues.
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Doenças Mitocondriais/metabolismo , Fosforilação Oxidativa , DNA Mitocondrial/genética , Humanos , Doenças Mitocondriais/genética , MutaçãoRESUMO
INTRODUCTION: Kearns-Sayre syndrome (KSS) is a mitochondrial disorder characterized by progressive external ophthalmoplegia, pigmentary retinopathy, onset before 20 years, and ragged-red fibers on muscle biopsy. KSS has been associated to mitochondrial DNA (mtDNA) mutations. We report neurological manifestations and mtDNA deletions in KSS. METHODS: Six KSS patients underwent neurological examination, biochemical analysis (muscle enzymes, lactate, cerebrospinal fluid analysis), electromicrography, muscle biopsy (Gomori stain, electronic microscopy), electrocardiogram, echocardiography, MRI/CT scan. MtDNA deletions were studied in blood and muscle samples using Southern blotting and long polymerase chain reaction. RESULTS: Four males and two females (mean age: 27.7 years; range: 17-42; mean age at onset: 8.2 years) were studied. Initial symptoms were ptosis and gaze restriction, fatigue, exercise intolerance and proximal limb weakness. Syncope and neurosensory hypoacusia were initial symptoms in two patients. All of them presented a unique deletion in the mitochondrial genome, in heteroplasmy, and their size was in the range of 4,420 and 9,437 basis pairs. Three of these deletions are reported for the first time in this article. Most of the deletions are flanked by small direct repeats elements. CONCLUSIONS: Proximal muscle weakness and fatigue appear frequently in KSS patients during follow up. The syndrome in these patients has been caused by mtDNA deletions.