Estudo comparativo dos níveis de aptidão física dos alunos dos 11 aos 14 anos com e sem prática de atividades físicas extracurriculares ao longo do ano letivo 2010/2011 : estudo caso

O estudo apresentado tem como objetivo avaliar os níveis de Aptidão Física de crianças e jovens dos 11 aos 14 anos da Freguesia de Bobadela, estabelecendo uma comparação entre aqueles que praticam Atividade Física somente através da Disciplina de Educação Física e os que para além desta realizam Atividades Físicas Extracurriculares. A amostra é constituída por 321 alunos de ambos os géneros, da Escola Básica Integrada de Bobadela, distrito de Lisboa, com idades compreendidas entre os 11 e os 14 anos. Tendo em conta os objetivos do estudo, a amostra foi dividida em dois grupos distintos, sendo que 148 alunos praticam Atividade Física Extracurricular, 81 do género masculino e 67 do género feminino, com uma média de 12,43 anos de idade, e 173 alunos que só praticam Atividade Física durante as aulas de Educação Física, 90 do género masculino e 83 do género feminino, com uma média de idades de 12,31 anos. Para a realização do estudo foi aplicada a bateria de testes do Fitnessgram de modo a avaliar a Aptidão Física das Crianças na dimensão motora (Flexibilidade – senta e alcança; Força Média – abdominal; Resistência – Vaivém e um questionário de prática desportiva fora do contexto escolar). A recolha de dados teve lugar entre 22 de Setembro e 26 de Maio de 2011. A apresentação dos resultados foi efetuada através do uso da estatística descritiva: media, desvio padrão, amplitude; e o teste T-Student. Concluímos que: 1 - No início do ano letivo não existem diferenças estatisticamente significativas entre géneros, em todas as capacidades motoras consideradas; 2- Em termos de evolução da NZSAF para a ZSAF, verifica-se uma melhoria das capacidades motoras em todas as faixas etárias de ambos os grupos, à exceção das raparigas não praticantes no teste da Força Média. A Flexibilidade dos Membros Inferiores foi mais acentuada nas raparigas de 11 anos, não praticantes (3.6%) e praticantes (4.5%). 3 – A percentagem mais elevada de evolução ocorre ao nível da Capacidade Aeróbia (nos rapazes (3.7%) e raparigas (3%) de 12 anos). 4 - Comparando o grupo de Praticantes e de Não Praticantes (rapazes e raparigas) com os valores de referência do Fitnessgram verificou-se que em relação à Aptidão Física, os Praticantes apresentaram maiores percentagens dentro do intervalo da Zona Saudável para todos os testes realizados.

Estudo de vinte casos de hiperadrenocorticismo no cão

O hiperadrenocorticismo canino consiste no conjunto de alterações físicas e bioquímicas resultantes da exposição prolongada e inapropriada, do organismo, a elevadas concentrações de cortisol. Esta dissertação teve como principal objectivo o estudo de vinte casos de hiperadrenocorticismo no cão, com base na recolha e interpretação de dados clínicos, laboratoriais e de imagem, efectuados durante o período de dois anos, entre Março de 2010 e Março de 2012, no Hospital Veterinário da FMVZ/UNESP em Botucatu. Constatou-se que a maioria das características individuais (idade, peso, raça e sexo), sinais clínicos e alterações laboratoriais (hemograma, bioquímicas sanguíneas e urianálise) comuns desta doença estavam presentes. Os cães do nosso estudo eram na sua maioria geriátricos, de raça miniatura como o caniche, com peso inferior a 20 Kg e do sexo feminino; estes apresentavam habituais sinais clínicos como poliúria, polidipsia, distensão abdominal, polifagia, fraqueza muscular, alterações respiratórias, cutâneas e neurológicas, e habituais alterações laboratoriais como trombocitose, linfopenia, eosinopenia, neutrofilia, aumento da fosfatase alcalina sérica, alanina aminotransferase, colesterol e triglicéridos. Alguns destes cães apresentaram ainda três das complicações mais comuns do hiperadrenocorticismo como hipertensão arterial, infecção do tracto urinário inferior e diabetes mellitus. Para chegar ao diagnóstico final realizou-se o teste de supressão de dexametasona a baixas doses em associação com a avaliação das glândulas adrenais através de ecografia, o qual nos permitiu obter a nossa amostra final, os vinte cães com hiperadrenocorticismo. Este estudo contribuiu para aprofundar o conhecimento relativamente às alterações clínicas, laboratoriais e de imagem presentes nos cães com hiperadrenocorticismo e demonstrou que a informação daí retirada é fundamental para chegar ao seu diagnóstico.

Miopatia atípica: análise de casos clínicos

A Miopatia atípica é uma doença emergente em alguns países europeus, que afecta cavalos de pasto, caracterizada por fraquez súbita, decúbito prolongado e degeneração muscular aguda. Tem-se verificado recentemente um aumento do número de surtos, incluindo em países em que a doença nunca fora diagnosticada anteriormente, o que justifica o presente estudo, que tem como objectivo a contribuição para a descrição do perfil epidemológico da MA, com base na descrição de dados geográficos, demográficos e clínicos de casos confirmados e suspeitos de MA, observados num Hospital Equino de referência, na Bélgica, durante o Outono de 2010. Foram incluídos na análise retrospectiva da série de casos clínicos estudados tanto a identificação fenotípica de cada indivíduo, assim como as respectivas práticas de maneio, incluindo condições de pastoreio, história clínica e achados bioquímicos e, sempre que possível, histopatológicos. Os sinais clínicos ocorreram em condições climáticas desfavoráveis. Os sintomas mais frequentes incluíram fraqueza e recusa em mover-se. As concentrações de creatinina quinase, CK, variaram entre 20360 UI/L a 213350 UI/L nos casos confirmados, CC e casos de elevada probabilidade, CEP para miopatia atípica, MA. A associação de MA com as condições climáticas sugere que o maneio das pastagens é de extrema importância na prevenção da condição.

Potranskrypcyjna regulacja ekspresji genu CELF1 - wpływ na patomechanizm dystrofii miotonicznej

Wydział Biologii: Instytut Biologii Molekularnej i Biotechnologii

Molecular, cellular and physiological investigation of myostatin propeptide-mediated muscle growth in adult mice

Inhibition of myostatin signalling or its biological activity has recently emerged as a potential remedial approach against muscle wasting and degenerative diseases such as muscular dystrophies. In the present study we systemically administered a recombinant AAV8 vector expressing a mutated myostatin propeptide (AAV8ProMyo) to healthy mice in order to assess its impact on the histological, cellular and physiological properties of the skeletal muscle, exploiting the fact that myostatin is naturally inhibited by its own propeptide. We report that a single intravenous administration of AAV8ProMyo leads to increases in muscle mass of tibialis anterior, extensor digitorum longus and gastrocnemius muscles 8 weeks post-injection and tibialis anterior, gastrocnemius and rectus femoris muscles 17 weeks post-injection. Moreover, treatment resulted in muscle fibre hypertrophy but not hyperplasia, with IIB myofibres responding to the greatest extent following propeptide-induced myostatin inhibition. Additionally, myofibre nuclear: cytoplasmic ratio was decreased in the AAV8ProMyo treated animals. Importantly, the hypertrophic EDL muscle 8 weeks after AAV8ProMyo treatment did not show the dramatic decrease in specific force displayed by the germline myostatin null mice. (C) 2009 Elsevier B.V. All rights reserved.

Origin and evolution of a myxozoan worm

Buddenbrockia pluinatellae is an active, muscular, worm-shaped parasite of freshwater bryozoans. This rare and enigmatic animal has been assigned to the Myxozoa on the basis of 18S ribosomal DNA sequences and the presence of malacosporean spores. Here we report cloning of four homologous protein-coding genes from Buddenbrockia worms, the putatively conspecific sac-shaped parasite originally described as Tetracapsula bryozoides and the related sac-shaped parasite Tetracapsuloides bryosalmonae, the causative agent of proliferative kidney disease in salmonid fish. Analyses are consistent with the hypothesis that Buddenbrockia is indeed a malacosporean myxozoan, but do not provide support for conspecificity with either T. bryozoides or T. bryosalmonae. Implications for the evolution of worm-like body plans in the Myxozoa are discussed.

Buddenbrockia is a Cnidarian worm

A major evolutionary divide occurs in the animal kingdom between the so-called radially symmetric animals, which includes the cnidarians, and the bilaterally symmetric animals, which includes all worm phyla. Buddenbrockia plumatellae is an active, muscular, parasitic worm that belongs to the phylum Myxozoa, a group of morphologically simplified microscopic endoparasites that has proved difficult to place phylogenetically. Phylogenetic analyses of multiple protein-coding genes demonstrate that Buddenbrockia is a cnidarian. This active muscular worm increases the known diversity in cnidarian body plans and demonstrates that a muscular, wormlike form can evolve in the absence of overt bilateral symmetry.

Os efeitos de um programa de exercícios domiciliares em pacientes com Paraparesia Espástica Tropical/Mielopatia Associada ao HTLV-1 (PET/MAH)

Introdução e Objetivos: Os efeitos da prática de exercícios sobre a funcionalidade de indivíduos com Paraparesia Espástica Tropical/Mielopatia Associada ao HTLV-1 (PET/MAH) são desconhecidos. O objetivo deste estudo é avaliar os efeitos de um Programa de Exercícios Domiciliares (PED) e a sua taxa de adesão em indivíduos com PET/MAH. Métodos: Vinte e três participantes com o diagnóstico de PET/MAH, marcha preservada e que não praticavam exercícios há pelo menos um mês foram submetidos ao PED de 20 semanas. Os desfechos primários incluíram os escores de força muscular, contração isométrica voluntária máxima (CIVM) e comprimento muscular dos membros inferiores, dor lombar e nos membros inferiores, EDSS, Escala de Incapacidade do IPEC, Índice de Barthel e SF-36. A taxa de adesão e os eventos adversos também foram mensurados e caracterizados. Resultados: No momento da análise os pacientes foram divididos em dois grupos de acordo com o teste Timed Up and Go (TUG) (<20s vs \226520s). O comprimento dos músculos isquiotibiais e plantiflexores, a CIVM dos membros inferiores e o componente \201CAspectos Sociais\201D da SF-36 apresentaram melhora significativa no grupo TUG <20s. Os indivíduos do grupo TUG \226520s melhoraram significativamente o componente \201CCapacidade Funcional\201D da SF-36. A taxa de adesão foi de 90% no total e os eventos adversos, como fadiga, dor muscular e caimbras foram de intensidade leve a moderada Discussão: Foi observada uma boa adesão ao PED, além de melhora significativa da incapacidade e da qualidade de vida dos indivíduos com PET/MAH. É possível que o grupo TUG \226520s apresente um maior componente neurodegenerativo e, portanto, uma menor probabilidade de incremento da funcionalidade. Conclusões: O PED foi eficaz em melhorar algumas incapacidades e a qualidade de vida dos indivíduos com PET/MAH. Tais resultados reforçam a necessidade de estratégias alternativas ao modelo ambulatorial, que ampliem a participação destas pessoas a programas de reabilitação

TRIM32 regulates skeletal muscle stem cell differentiation and is necessary for normal adult muscle regeneration

Limb girdle muscular dystrophy type 2H (LGMD2H) is an inherited autosomal recessive disease of skeletal muscle caused by a mutation in the TRIM32 gene. Currently its pathogenesis is entirely unclear. Typically the regeneration process of adult skeletal muscle during growth or following injury is controlled by a tissue specific stem cell population termed satellite cells. Given that TRIM32 regulates the fate of mammalian neural progenitor cells through controlling their differentiation, we asked whether TRIM32 could also be essential for the regulation of myogenic stem cells. Here we demonstrate for the first time that TRIM32 is expressed in the skeletal muscle stem cell lineage of adult mice, and that in the absence of TRIM32, myogenic differentiation is disrupted. Moreover, we show that the ubiquitin ligase TRIM32 controls this process through the regulation of c-Myc, a similar mechanism to that previously observed in neural progenitors. Importantly we show that loss of TRIM32 function induces a LGMD2H-like phenotype and strongly affects muscle regeneration in vivo. Our studies implicate that the loss of TRIM32 results in dysfunctional muscle stem cells which could contribute to the development of LGMD2H.

Chronic systemic therapy with low-dose morpholino oligomers ameliorates the pathology and normalizes locomotor behavior in mdx Mice

The administration of antisense oligonucleotides (AOs) to skip one or more exons in mutated forms of the DMD gene and so restore the reading frame of the transcript is one of the most promising approaches to treat Duchenne muscular dystrophy (DMD). At present, preclinical studies demonstrating the efficacy and safety of long-term AO administration have not been conducted. Furthermore, it is essential to determine the minimal effective dose and frequency of administration. In this study, two different low doses (LDs) of phosphorodiamidate morpholino oligomer (PMO) designed to skip the mutated exon 23 in the mdx dystrophic mouse were administered for up to 12 months. Mice treated for 50 weeks showed a substantial dose-related amelioration of the pathology, particularly in the diaphragm. Moreover, the generalized physical activity was profoundly enhanced compared to untreated mdx mice showing that widespread, albeit partial, dystrophin expression restores the normal activity in mdx mice. Our results show for the first time that a chronic long-term administration of LDs of unmodified PMO, equivalent to doses in use in DMD boys, is safe, significantly ameliorates the muscular dystrophic phenotype and improves the activity of dystrophin-deficient mice, thus encouraging the further clinical translation of this approach in humans.

Codon and mRNA sequence optimization of microdystrophin transgenes improves expression and physiological outcome in dystrophic mdx mice following AAV2/8 gene transfer

Duchenne muscular dystrophy is a fatal muscle-wasting disorder. Lack of dystrophin compromises the integrity of the sarcolemma and results in myofibers that are highly prone to contraction-induced injury. Recombinant adenoassociated virus (rAAV)-mediated dystrophin gene transfer strategies to muscle for the treatment of Duchenne muscular dystrophy (DMD) have been limited by the small cloning capacity of rAAV vectors and high titers necessary to achieve efficient systemic gene transfer. In this study, we assess the impact of codon optimization on microdystrophin (ΔAB/R3-R18/ΔCT) expression and function in the mdx mouse and compare the function of two different configurations of codon-optimized microdystrophin genes (ΔAB/R3-R18/ΔCT and ΔR4-R23/ΔCT) under the control of a muscle-restrictive promoter (Spc5-12). Codon optimization of microdystrophin significantly increases levels of microdystrophin mRNA and protein after intramuscular and systemic administration of plasmid DNA or rAAV2/8. Physiological assessment demonstrates that codon optimization of ΔAB/R3-R18/ΔCT results in significant improvement in specific force, but does not improve resistance to eccentric contractions compared with noncodon-optimized ΔAB/ R3-R18/ΔCT. However, codon-optimized microdystrophin ΔR4-R23/ΔCT completely restored specific force generation and provided substantial protection from contraction-induced injury. These results demonstrate that codon optimization of microdystrophin under the control of a muscle-specific promoter can significantly improve expression levels such that reduced titers of rAAV vectors will be required for efficient systemic administration.

Delivery of AAV2/9-microdystrophin genes incorporating helix 1 of the coiled-coil motif in the C-terminal domain of dystrophin improves muscle pathology and restores the level of α1-syntrophin and α-dystrobrevin in skeletal muscles of mdx mice. Level of α1-Syntrophin and α-Dystrobrevin in Skeletal Muscles of mdx Mice

Duchenne muscular dystrophy is a severe X-linked inherited muscle wasting disorder caused by mutations in the dystrophin gene. Adeno-associated virus (AAV) vectors have been extensively used to deliver genes efficiently for dystrophin expression in skeletal muscles. To overcome limited packaging capacity of AAV vectors (<5 kb), truncated recombinant microdystrophin genes with deletions of most of rod and carboxyl-terminal (CT) domains of dystrophin have been developed. We have previously shown the efficiency of mRNA sequence–optimized microdystrophin (ΔR4-23/ΔCT, called MD1) with deletion of spectrin-like repeat domain 4 to 23 and CT domain in ameliorating the pathology of dystrophic mdx mice. However, the CT domain of dystrophin is thought to recruit part of the dystrophin-associated protein complex, which acts as a mediator of signalling between extracellular matrix and cytoskeleton in muscle fibers. In this study, we extended the ΔR4-23/ΔCT microdystrophin by incorporating helix 1 of the coiled-coil motif in the CT domain of dystrophin (MD2), which contains the α1-syntrophin and α-dystrobrevin binding sites. Intramuscular injection of AAV2/9 expressing CT domain–extended microdystrophin showed efficient dystrophin expression in tibialis anterior muscles of mdx mice. The presence of the CT domain of dystrophin in MD2 increased the recruitment of α1-syntrophin and α-dystrobrevin at the sarcolemma and significantly improved the muscle resistance to lengthening contraction–induced muscle damage in the mdx mice compared with MD1. These results suggest that the incorporation of helix 1 of the coiled-coil motif in the CT domain of dystrophin to the microdystrophins will substantially improve their efficiency in restoring muscle function in patients with Duchenne muscular dystrophy.

MiR-375 is essential for human spinal motor neuron development and may be involved in motor neuron degeneration

The transcription factor REST is a key suppressor of neuronal genes in non-neuronal tissues. REST has been shown to suppress pro-neuronal microRNAs in neural progenitors indicating that REST-mediated neurogenic suppression may act in part via microRNAs. We used neural differentiation of Rest-null mouse ESC to identify dozens of microRNAs regulated by REST during neural development. One of the identified microRNAs, miR-375, was upregulated during human spinal motor neuron development. We found that miR-375 facilitates spinal motor neurogenesis by targeting the cyclin kinase CCND2 and the transcription factor PAX6. Additionally, miR-375 inhibits the tumor suppressor p53 and protects neurons from apoptosis in response to DNA damage. Interestingly, motor neurons derived from a spinal muscular atrophy patient displayed depressed miR-375 expression and elevated p53 protein levels. Importantly, SMA motor neurons were significantly more susceptible to DNA damage induced apoptosis suggesting that miR-375 may play a protective role in motor neurons.

Neuromotor tolerability and behavioural characterisation of cannabidiolic acid, a phytocannabinoid with therapeutic potential for anticipatory nausea

Rationale: Anticipatory nausea (AN) is a poorly controlled side-effect experienced by chemotherapy patients. Currently, pharmacotherapy is restricted to benzodiazepine anxiolytics, which have limited efficacy, significant sedative effects, and induce dependency. The non-psychoactive phytocannabinoid, cannabidiolic acid (CBDA), has shown considerable efficacy in pre-clinical AN models, however determination of its neuromotor tolerability profile is crucial to justify clinical investigation. Provisional evidence for appetite-stimulating properties also requires detailed investigation. Objectives: To assess the tolerability of CBDA in locomotor activity, motor coordination and muscular strength tests, and additionally for ability to modulate feeding behaviours. Methods: Male Lister hooded rats administered CBDA (0.05-5 mg/kg; p.o.) were assessed in habituated open field (for locomotor activity), static beam and grip strength tests. A further study investigated whether these CBDA doses modulated normal feeding behaviour. Finally, evidence of anxiolytic-like effects in the habituated open field prompted testing of 5 mg/kg CBDA for anxiolytic-like activity in unhabituated open field, light/dark box and novelty-supressed feeding (NSF) tests. Results: CBDA had no adverse effects upon performance in any neuromotor tolerability test, however anxiolytic-like behaviour was observed in the habituated open field. Normal feeding behaviours were unaffected by any dose. CBDA (5 mg/kg) abolished the increased feeding latency in the NSF test induced by the 5-HT1AR antagonist, WAY-100,635, indicative of anxiolytic-like effects, but had no effect on anxiety-like behaviour in the novel open field or light/dark box. Conclusions: CBDA is very well tolerated and devoid of the sedative side-effect profile of benzodiazepines, justifying its clinical investigation as a novel AN treatment.

Blockade of ActRIIB signaling triggers muscle fatigability and metabolic myopathy

Myostatin regulates skeletal muscle size via the activin receptor IIB (ActRIIB). However, its effect on muscle energy metabolism and energy dependent muscle function remains largely unexplored. This question needs to be solved urgently since various therapies for neuromuscular diseases based on blockade of ActRIIB signaling are being developed. Here we show in mice that four months of pharmacological abrogation of ActRIIB signaling by treatment with soluble ActRIIB-Fc triggers extreme muscle fatigability. This is associated with elevated serum lactate levels and a severe metabolic myopathy in the mdx mouse, an animal model of Duchenne muscular dystrophy. Blockade of ActRIIB signaling down-regulates Porin, a crucial ADP/ATP shuttle between cytosol and mitochondrial matrix leading to a consecutive deficiency of oxidative phosphorylation as measured by in vivo Phophorus Magnetic Resonance Spectroscopy (31P-MRS). Further, ActRIIB blockade reduces muscle capillarization, which further compounds the metabolic stress. We show that ActRIIB regulates key determinants of muscle metabolism, such as Pparβ, Pgc1α, and Pdk4 thereby optimizing different components of muscle energy metabolism. In conclusion, ActRIIB signaling endows skeletal muscle with high oxidative capacity and low fatigability. The severe metabolic side effects following ActRIIB blockade caution against deploying this strategy, at least in isolation, for treatment of neuromuscular disorders.