André Yui Aihara

Strength Training with Blood Flow Restriction Diminishes Myostatin Gene Expression

PURPOSE The aim of the study was to determine whether the similar muscle strength and hypertrophy responses observed after either low-intensity resistance exercise associated with moderate blood flow restriction or high-intensity resistance exercise are associated with similar changes in messenger RNA (mRNA) expression of selected genes involved in myostatin (MSTN) signaling. METHODS Twenty-nine physically active male subjects were divided into three groups: low-intensity (20% one-repetition maximum (1RM)) resistance training (LI) (n = 10), low-intensity resistance exercise associated with moderate blood flow restriction (LIR) (n = 10), and high-intensity (80% 1RM) resistance exercise (HI) (n = 9). All of the groups underwent an 8-wk training program. Maximal dynamic knee extension strength (1RM), quadriceps cross-sectional area (CSA), MSTN, follistatin-like related genes (follistatin (FLST), follistatin-like 3 (FLST-3)), activin IIb, growth and differentiation factor-associated serum protein 1 (GASP-1), and MAD-related protein (SMAD-7) mRNA gene expression were assessed before and after training. RESULTS Knee extension 1RM significantly increased in all groups (LI = 20.7%, LIR = 40.1%, and HI = 36.2%). CSA increased in both the LIR and HI groups (6.3% and 6.1%, respectively). MSTN mRNA expression decreased in the LIR and HI groups (45% and 41%, respectively). There were no significant changes in activin IIb (P > 0.05). FLST and FLST-3 mRNA expression increased in all groups from pre- to posttest (P < 0.001). FLST-3 expression was significantly greater in the HI when compared with the LIR and LI groups at posttest (P = 0.024 and P = 0.018, respectively). GASP-1 and SMAD-7 gene expression significantly increased in both the LIR and HI groups. CONCLUSIONS We concluded that LIR was able to induce gains in 1RM and quadriceps CSA similar to those observed after traditional HI. These responses may be related to the concomitant decrease in MSTN and increase in FLST isoforms, GASP-1, and SMAD-7 mRNA gene expression.

Changes in Exercises Are More Effective Than in Loading Schemes to Improve Muscle Strength

Abstract Fonseca, RM, Roschel, H, Tricoli, V, de Souza, EO, Wilson, JM, Laurentino, GC, Aihara, AY, de Souza Leão, AR, and Ugrinowitsch, C. Changes in exercises are more effective than in loading schemes to improve muscle strength. J Strength Cond Res 28(11): 3085–3092, 2014—This study investigated the effects of varying strength exercises and loading scheme on muscle cross-sectional area (CSA) and maximum strength after 4 strength training loading schemes: constant intensity and constant exercise (CICE), constant intensity and varied exercise (CIVE), varied intensity and constant exercise (VICE), varied intensity and varied exercise (VIVE). Forty-nine individuals were allocated into 5 groups: CICE, CIVE, VICE, VIVE, and control group (C). Experimental groups underwent twice a week training for 12 weeks. Squat 1 repetition maximum was assessed at baseline and after the training period. Whole quadriceps muscle and its heads CSA were also obtained pretraining and posttraining. The whole quadriceps CSA increased significantly (p ⩽ 0.05) in all of the experimental groups from pretest to posttest in both the right and left legs: CICE: 11.6 and 12.0%; CIVE: 11.6 and 12.2%; VICE: 9.5 e 9.3%; and VIVE: 9.9 and 11.6%, respectively. The CIVE and VIVE groups presented hypertrophy in all of the quadriceps muscle heads (p ⩽ 0.05), whereas the CICE and VICE groups did not present hypertrophy in the vastus medialis and rectus femoris (RF), and in the RF muscles, respectively (p > 0.05). The CIVE group had greater strength increments than the other training groups (effect size confidence limit of the difference [ESCLdiff] CICE: 1.41−1.56; VICE: 2.13–2.28; VIVE: 0.59–0.75). Our findings suggest: (a) CIVE is more efficient to produce strength gains for physically active individuals; (b) as long as the training intensity reaches an alleged threshold, muscle hypertrophy is similar regardless of the training intensity and exercise variation.

Avaliação por imagem das lesões da placa de crescimento

The structures responsible for the growth of bones include the physis (also called growth plate) and the epiphysis. Affections involving patients with immature skeletons, i.e., with a still open growth plate, may affect the bone growth, resulting in complications such as growth arrest, limb shortening and angular deformities. Traumatic conditions, many times resulting in epiphyseal fractures, are the most frequent cause of growth plate injuries. A careful evaluation of these patients by means of currently available imaging methods, especially radiography, computed tomography and magnetic resonance imaging, allows an early diagnosis of the involvement of structures related to the bone growth, besides an appropriate management, reducing the probability of secondary complications.

Osteocondrite (osteocondrose) dissecante (OCD)

Osteocondrite dissecante (OCD) e uma condicao adquirida de etiologia desconhecida, caracterizada pela necrose focal do osso subcondral de articulacoes(1). A importância do diagnostico precoce desta entidade deve-se ao potencial de cura espontânea num momento inicial. Ocorre geralmente em adolescentes e adultos jovens do sexo masculino, sendo o joelho o local mais acometido, seguido pelo talus. O termo mais adequado para esta alteracao e osteocondrose dissecante, pois se sabe que nao ha processo inflamatorio local. Existem duas teorias quanto a etiopatogenia, sao elas: a teoria traumatica/mecânica, relacionada com o aumento da atividade e microtraumas repetitivos, e a predisposicao familiar/hereditaria(2). Entretanto, a correlacao anatomopatologica e o curso in vivo da OCD ainda sao baseados em observacoes cirurgicas e histologicas, e em estudos experimentais(2). Inicialmente ha demarcacao do osso subcondral com necrose, sem comprometimento macroscopico da cartilagem sobrejacente. Posteriormente, adjacente ao osso necrotico, forma-se uma zona de transicao, que e preenchida por tecido de granulacao, composta por tecido fibrocartilaginoso e capilares vasculares. Nesta etapa, a lesao pode ter cura espontânea, ou evoluir com separacao do fragmento osseo com ou sem alteracao cartilaginosa. Por fim, ha extrusao do fragmento, com formacao de corpo livre intra articular e cratera na superficie ossea(2,3). Ha autores que separam a OCD em duas entidades, a OCD juvenil e a OCD do adulto, diferenciadas pelo inicio dos sintomas com relacao ao fechamento da placa epifisaria. O motivo dessa distincao deve-se ao melhor prognostico das lesoes na forma juvenil(3). Como tambem, a longo prazo, a OCD do adulto predispoe a alteracoes degenerativas secundarias, com antecipacao dos sintomas em cerca de 10 anos quando comparado a individuos saos(2). Nao devemos confundir a OCD com osteonecrose pos corticoterapia, hemoglobinopatias, doenca de Gaucher, doenca de Caisson’s(2) ou com a “osteonecrose espontânea”(2,4).

Artro-ressonância do ombro na instabilidade anterior

O ombro e a articulacao com a maior capacidade e amplitude de movimento, tendo mais de 180 graus de amplitude em todos os planos. Devido a esta grande mobilidade, a articulacao glenoumeral e uma das mais instaveis e frequentemente luxadas do corpo, correspondendo a cerca de 50% de todas as luxacoes(1, 2). Os estabilizadores estaticos do ombro sao: glenoide ossea, labio glenoidal, capsula articular, ligamentos glenoumerais e intervalo dos rotadores (espaco entre a margem anterior do musculo supraespinhal e a margem superior do musculo subescapular, contendo no seu interior o tendao da cabeca longa do biceps, ligamento coracoumeral e o ligamento glenoumeral superior). Os estabilizadores dinâmicos sao: musculos do manguito rotador e escapuloumerais. O balanco entre eles e responsavel pela estabilidade da articulacao do ombro(3, 4, 5). Para estudo dessas estruturas, a artrografia e o melhor metodo. A distensao da capsula articular permite avaliar melhor sua morfologia, bem como do labio glenoidal, dos ligamentos glenoumerais, do intervalo dos rotadores, da face articular do manguito rotador, de acompanhamento pos-operatorio da articulacao glenoumeral e do manguito rotador(6). A artro-ressonância magnetica constitui-se no metodo de imagem de escolha, pois permite a analise mais precisa das estruturas mencionadas, assim como dos demais componentes da articulacao e tambem das estruturas relacionadas a essa articulacao, como os ventres musculares dos componentes do manguito rotador e do tendao da cabeca longa do biceps. INSTABIlIDADE glENOuMERAl

Metatarsalgias: diagnóstico diferencial por meio da ressonância magnética

Several lesions may cause metatarsalgia whose clinical manifestations may be non-specific. Magnetic resonance imaging associated with other imaging methods and clinical data frequently can contribute to detection of these lesions, allowing a reasonably precise diagnosis to be considered. Our purpose is to describe and illustrate, by means of magnetic resonance imaging, main diseases causing metatarsalgia.

Imaging evaluation of bone tumors

The radiographic approach to bone tumors consists in analyz-ing a certain lesion in an organized manner, paying attention tospecific radiographic features such as location, margins and tran-sition zones, periosteal reaction patterns, mineralization, lesionsize, and whether or not soft tissue components are present

Raízes meniscais: anatomia e avaliação por meio da ressonância magnética

As raizes anteriores e posteriores sao os componentes meniscais que fixam os meniscos nos platos tibiais proximo a insercao dos ligamentos cruzados (Figura 1). As raizes, tambem chamadas de enteses, sao estruturas criticas para a funcao biomecânica dos meniscos, porque lesoes dessa regiao, assim como lesoes radiais extensas e lesoes complexas, interrompem as fibras de colageno circunferenciais e determinam uma expansao radial do menisco, com subluxacao e extrusao deste. Assim, forcas axiais compressivas sao transmitidas diretamente para a cartilagem articular, o que leva a degeneracao precoce da cartilagem e a osteoartrose(1,2). O reconhecimento de lesoes meniscais comprometendo essas estruturas tem, portanto, relevância clinica, pois seu diagnostico propicia formas mais adequadas de tratamento, evitando progressao das lesoes meniscais e das alteracoes degenerativas articulares.

Image diagnosis for metatarsophalangeal joint instability

A instabilidade metatarsofalângica (MTF) e definida como um processo inflamatorio agudo, subagudo, e menos comumente cronico das estruturas periarticulares que estabilizam uma ou mais articulacoes MTFs. O diagnostico desta condicao frequentemente nao e feito nem considerado; caso nao tratado pode evoluir com enfraquecimento e/ou lesao da capsula ou da placa plantar alem de instabilidade articular, com subsequente deformidade do dedo(1). A segunda articulacao MTF e a mais acometida(2), sendo o desvio geralmente medial, menos comumente lateral, podendo estar acompanhado de migracao dorsal da falange proximal(1). O progresso de subluxacao ou deslocamento do dedo pode ser rapido ou lento. Existem fatores desencadeadores intrinsecos e extrinsecos do processo inflamatorio inicial(3). Os fatores intrinsecos incluem doenca inflamatoria articular como artrite reumatoide, doenca do tecido conjuntivo e outras sinovites articulares que provocam a deterioracao dos ligamentos colaterais e da capsula articular, com subsequente lesao ou ruptura da placa plantar. As causas extrinsecas compreendem o halux valgo, o segundo osso metatarsico longo (ou o primeiro curto) e a hipermobilidade do primeiro raio que podem predispor para a sinovite aguda, gerando distensao capsular e lesao da placa plantar. O desvio lateral do halux tambem pode estar associado as forcas que determinam hiper extensao da segunda articulacao MTF, resultando na perda da estabilizacao da musculatura intrinseca. Essas condicoes combinadas predispoem a subluxacao do segundo dedo, lesao ou ruptura da placa plantar com possivel deslocamento da falange. ANATOMIA E BIOMECÂNICA

Cognitive map to support the diagnosis of solitary bone tumors in pediatric patients

Abstract Objective To present a cognitive map to support the radiological diagnosis of solitary bone tumors, as well as to facilitate the determination of the nature of the tumor (benign or malignant), in pediatric patients. Materials and Methods We selected 28 primary lesions in pediatric patients, and we identified the findings typically associated with each of the diagnoses. The method used for the construction of the final cognitive map was the Bayesian belief network model with backward chaining. Results We developed a logical, sequential structure, in the form of a cognitive map, based on the Bayesian belief network model, with the intention of simulating the sequence of human thinking, in order to minimize the number of unnecessary interventions and iatrogenic complications arising from the incorrect evaluation of bone lesions. Conclusion With this map, it will be possible to develop an application that will provide support to physicians and residents, as well as contributing to training in this area and consequently to a reduction in diagnostic errors in patients with bone lesions.