The aim of our study was to explore the age related changes of the fibre type composition of the human psoas major muscle. Moreover, we wanted to compare the fibre type composition of the left and right muscle. Muscle samples were collected from 15 young and 15 old males. Type I, IIA and IIX muscle fibres were typed using myosin heavy chain identification. The serial transverse sections were an...

BACKGROUND Impaired balance, loss of mobility and falls are major problems associated with changes in muscle in older adults. However, the extent to which muscle composition and related performance measures for different lower limb muscles are associated with falls in older individuals is unclear. This study evaluated lower limb muscle attenuation, intramuscular adipose tissue (IMAT) infiltrati...

Body composition is associated with risk of disease progression and treatment complications in a variety conditions. Therefore, quantification skeletal muscle mass adipose tissues on Computed Tomography (CT) and/or Magnetic Resonance Imaging (MRI) may inform surgery evaluation prognosis. This article describes two methods originally described by Mourtzakis et al. Avrutin al.: tissue segmentatio...

Skeletal muscle fibers are composed of three structural elements, each contributing a unique aspect of muscle function, yet each 'competing' in a sense for space inside the cell. The volume occupied by myofibrils determines the force of contraction, the volume of sarcoplasmic reticulum sets the rate of onset and relaxation of a fiber's contraction and hence contraction frequency, and the volume...

Detrimental changes in the composition and function of rotator cuff (RC) muscles are hallmarks of RC disease progression. Previous studies have demonstrated both atrophic and degenerative muscle loss in advanced RC disease. However, the relationship between gene expression and RC muscle pathology remains poorly defined, in large part due to a lack of studies correlating gene expression to tissu...

The changes in muscle composition which occur in disturbances of extracellular electrolyte composition were systematically described by Darrow, et al.8"' and confirmed by others.7"8 However, the mechanism responsible for these changes has not been satisfactorily elucidated. It is the purpose of this paper to describe briefly the composition of muscle in the major disturbances of acid-base balan...