3+4+Supplementum/2012 - Společnost pro pojivové tkáně

Fig. 3A Fig. 3B Fig. 4A
Fig. 4B
element) is that the weight unit of this tissue
(e.g. 1 g or 1 mg) occupies less volume
than at the beginning of the thickening
process. This means that the bone tissue
has grown, i.e. its density has increased,
and thus the resultant volume change
of the bone tissue is less than zero. The
speeds of biochemical reactions are
influenced not only by chemical and
genetic effects, but also by mechanical
(biomechanical) effects. Generally, speed/
rate speed k j (of the j th biochemical reaction,
j = 1, 3, 4, 5) is the function both of
volume changes η j of the examined reactant
components of the tissue molecular
mixtures and of stress changes ∆p = p – p e,
where p e is the stress in the bone tissue
element in the steady state. for the
speed of the j th biochemical reaction
(j = 1, 3, 4, 5) of the remodelled bone tissue,
the exponential equation applies:
ambul_centrum@volny.cz
kj = Aje -η j∆p , where
∆p are stress changes in the bone tissue
element which take place under
the influence of primary mechanical
effects (changes of stress/strain tensors,
e.g. while walking);
ηj are volume changes of the examined
reactant components in the bone
tissue element that arose as a consequence
of:
a) the effect of chemical substances
(that are primarily initiated by
mechanical effects), and that cause
volume changes ηjm of the examined
reactant components (e.g. by the shear
flow of the extracellular liquid in the
lacunae of osteocytes);
b) the effect of chemical substances
transformed in cells at a „switchedoff“
genome mechanism which pri-
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