Using digital 3D skull models, researchers compared the jaw muscles of humans to our close relatives, including living species such as chimpanzees, gorillas, orangutans, and extinct ones like Paranthropus boisei (sometimes called "Nutcracker Man").
Atrophic and morphological changes were observed in cardiac muscles of humans and animals after their exposure to conditions of both simulated [ 19] and real [ 20, 21] microgravity.
Although the occurrence of muscle spindles (MS) is quite high in most skeletal muscles of humans, few MS, or even absence, have been reported in digastric and mylohyoideus muscles.
It is likely that oral MSG consumption increases glutamate concentration in the masseter muscle of human subjects and that this underlies the mechanical sensitization of the masseter muscle seen in the present study.
Previously, it has been observed that there may be increased transcriptional activation of FRG1, FRG2 and ANT1, the three genes upstream of the D4Z4 tandem repeat elements, in muscle of human FSHD patients [28]; however, these results were not observed in another patient study [32].
Previous studies also implicated decreased oxidative capacities of skeletal muscle of human diabetics as contributory to insulin resistance [ 16].
