We do not model quiescence explicitly because the substrate concentration in the central regions of our simulated tumors is nearly zero, so the cells there barely grow (see Mathematical Structure of the Tumor Model), effectively behaving like quiescent cells.
Quiescent neuroblasts, like quiescent neural stem cells of the mammalian SVZ and SGZ, exhibit a more complex morphology than proliferating cells (Ma et al., 2009).
It will be interesting to determine whether the latency-like quiescent state of infection is the result of IFNalpha directly promoting the establishment of latency/quiescence, or, alternatively, of an IFNalpha-mediated inhibition of lytic replication that indirectly promotes latency/quiescence.
Several recent studies have demonstrated that mitochondria are gradually rejuvenated to an ESC-like "quiescent state" during cellular reprogramming [ 27– 30].
And like the quiescent state, excited states of a medium are usually stationary states in some appropriate comoving frame, for example, along the x-direction with ξ = x − c t. Furthermore, the threshold is related to an unstable stationary state, the critical nucleation solution, usually in another comoving frame including c = 0.
In humans, like animals, quiescent immobility is an adaptive response that occurs in response to severe visceral, skeletal, muscle, or joint pain (see Vignette 16) or to a stressful event (see Vignette 17).
Such a shift into a quiescent-like state likely triggers adaptive cytoprotection.
Despite this commonality, the mechanisms underlying the transitions from regular bursts to the sigh-like burst and from the quiescent plateau to the sigh-like spike differ in the two models.
Culture of hepatic cells on Matrigel, a relatively soft basement membrane-like matrix, retains the quiescent nature of hepatic stellate cells [ 59].
Stellate cell activation is a key event in liver fibrosis, and it involves the process of transition of a quiescent, adipose-like vitamin-A storing cell to a highly fibrogenic cell [ 41].
To explain this finding mechanistically, it has been hypothesized that CD25+ AML blasts are enriched in chemoresistant leukemia stem cells (LSCs), as they bear an LSC-like molecular signature, are quiescent and can establish AML in xenograft models.
