Myocardial Layer-Specific Strain Analysis in Children with Mitochondrial Disease

PURPOSE: Children with mitochondrial disease (MD) have clinical phenotypes that are more severe than those found in adults. In this study, we assessed cardiac function in children with MD using conventional and advanced echocardiographic measurements, explored any unique patterns present, and investigated the development of early cardiomyopathy (CMP). MATERIALS AND METHODS: We retrospectively reviewed the medical records of 33 children with MD. All patients underwent transthoracic echocardiography with conventional and advanced myocardial analysis. We compared all data between patients and an age-matched healthy control group. RESULTS: Conventional echocardiographic diastolic measurements of mitral E, E/A, and tissue Doppler E′ were significantly lower and E/E′ was significantly higher in children with MD, compared with the measurements from the control group. There was no significant difference in longitudinal and radial strain between the groups. Circumferential strain in the endocardium (p=0.161), middle myocardium (p=0.008), and epicardium (p=0.042) were lower in patients, compared to the values in controls. Circumferential strain was correlated with E′ (p 0.60). CONCLUSION: In children with MD, myocardial circumferential strain may develop early in all three layers, even with normally preserved longitudinal and radial strain. This may be an early diagnostic indicator with which to predict CMP in this patient population.

The Newcastle Pediatric Mitochondrial Disease Scale: translation and cultural adaptation for use in Brazil / Escala Pediátrica de Doença Mitocondrial de Newcastle: tradução e adaptação cultural para uso no Brasil

ABSTRACT Objective The aim of this study was to translate and adapt the Newcastle Paediatric Mitochondrial Disease Scale (NPMDS) to Portuguese for use in Brazil. Methods The scale was applied in 20 pediatric patients with mitochondrial disease, in three groups: myopathy (n = 4); Leigh syndrome (n = 8); and encephalomyopathy (n = 8). Scores were obtained for the various dimensions of the NPMDS, and comparisons were drawn between the groups. Results There was a statistically significant difference between the myopathy group and the Leigh syndrome group (p = 0.0085), as well as between the myopathy and encephalomyopathy groups (p = 0.01). Conclusions The translation of the NPMDS, and its adaptation to the socioeconomic and cultural conditions in Brazil, make the NPMDS score useful as an additional parameter in the evaluation and monitoring of pediatric patients with MD in Brazil.

RESUMO Objetivo O objetivo do presente estudo foi realizar a tradução e adaptação da escala NPMDS para a população brasileira. Métodos A escala foi aplicada em 20 crianças e adolescentes com doença mitocondrial (DM) divididos em três grupos: miopatia (n=4), síndrome de Leigh (n=8) e encefalomiopatia (n=8). Obteve-se os escores separados das dimensões da escala NPMDS, foram realizadas comparações entre os escores da NPMDS nos diferentes grupos. Conclusão A tradução da escala NPMDS e sua adequação as condições socioeconômicas e culturais de nossa população tornam este instrumento um parâmetro adicional na avaliação e acompanhamento de pacientes pediátricos com DM.

Mitochondria and the central nervous system: searching for a pathophysiological basis of psychiatric disorders

Introduction: Mitochondrial dysfunction has been postulated to participate in the development of many neuropsychiatric disorders, but there is no consensus as to its role. The aim of this paper is to review recent studies and to outline the current understanding of the association between mitochondrial dysfunction and psychiatric disorders. Methodology: We reviewed articles that evaluated mitochondrial dysfunction and psychiatric disorders, with a particular focus on depression, bipolar disorder, anxiety disorders, obsessive-compulsive disorder, and autism spectrum disorder, and the association between mitochondrial dysfunction and development of these disorders. Results: Evidence suggests that alterations in mitochondrial morphology, brain energy metabolism, and mitochondrial enzyme activity may be involved in the pathophysiology of different neuropsychiatric disorders, given their key role in energy metabolism in the cell. Conclusions: Understanding the interactions between mitochondrial dysfunction and development of psychiatric disorders may help establish more effective therapeutic strategies for these disorders and thus lead to better outcomes for affected subjects. .

Ataxia crónica en pediatría / [Chronic ataxia in childhood].

Chronic ataxias are an heterogeneous group of disorders that affect the child at different ages. Thus, the congenital forms, generally non progressive are observed from first months of life and are expressed by hypotonia and motor delay long before the ataxia became evident. The cerebral magnetic resonance images (MRI) may be diagnostic in some pictures like Joubert syndrome. The group of progressive hereditary ataxias, usually begin after the infant period. The clinical signs are gait instability and ocular apraxia that can be associated with oculocutaneous telangiectasias (ataxia-telangiesctasia) or with sensory neuropathy (Friedreich ataxia). In this review are briefly described congenital ataxias and in more detailed form the progressive hereditary ataxias autosomal recessive, autosomal dominants and mitochondrials. The importance of genetic study is emphasized, because it is the key to obtain the diagnosis in the majority of these diseases. Although now there are no treatments for the majority of progressive hereditary ataxias, some they have like Refsum disease, vitamine E deficiency, Coenzyme Q10 deficiency and others, thus the diagnosis in these cases is even more important. At present the diagnosis of childhood hereditary ataxia not yet treatable is fundamental to obtain suitable handling, determine a precise outcome and to give to the family an opportune genetic counseling.

Papel crucial de la mitocondria en la muerte celular programada / Crucial role of mitochondria in the programmed death of cells

La apoptosis se ha relacionado con importantes procesos, como el desarrollo embrionario y la órgano-génesis, el mantenimiento del número adecuado de células y la eliminación de aquellas dañadas, envejecidas o potencialmente peligrosas. Se realizó una revisión bibliográfica sobre el papel central que juega la mitocondria en la ejecución, amplificación y regulación de la apoptosis, las principales moléculas implicadas, las alteraciones morfológicas y bioquímicas que sufre esta organela durante este evento, entre ellas la liberación de proteínas desde el espacio ínter membranoso, cada una con funciones pro apoptóticas claves y destinos diferentes, la apertura del poro de transición de permeabilidad, las alteraciones en la homeostasis del Ca2+ y la formación del apoptosoma en el citosol. El conocimiento de todos los actores del proceso apoptótico y la profundización del papel exacto que ellos juegan, nos acerca al entendimiento de procesos fisiológicos y patológicos que cursan con incremento o inhibición de la apoptosis

The apoptosis has been related to significant processes including the embryo development and the organogenesis, the maintenance of the appropriate number of cells and the elimination of those damaged, aged or potentially dangers. A bibliographic review was made on the key role playing the mitochondria in the carrying out, amplification and regulation of apoptosis, the main implicated molecules, the morphological and biochemical alterations suffered by this organelle during this event, among them the release or proteins from the inter-membranous space, each with pro-apoptosis key functions and different fates, the opening of the permeability transition pore, the alterations of homeostasis of Ca2+, and the formation of apoptosome in cytosol. The knowledge of all participants of apoptosis process approach us to understanding of physiological and pathological processes accounting for apoptosis increase of inhibition