Diurnal variations of serum β2-microglobulin in multiple myeloma

Chronobiological circadian aspects of serum lactate dehydrogenase and serum thymidine kinase in monitoring multiple myeloma

“…This hypothesis seems to be confirmed by the observation that the relapsed patients present the same sLDH and sTK circadian rhythms. Moreover, it is worth noting that a similar circadian pattern has been observed in untreated and treated MM patients for many other variables [2,4,5] that estimate myeloma cell activity. In other words, the presence of significant circadian rhythms for sLDH and sTK values in untreated and relapsed MM patients seems to be due to a synchronization in neoplastic activity.…”

“…Thus, the relative loss of the two circadian rhythms in treated patients could be related to the cell neoplastic activity and to the effect of therapy that inhibits proliferation; this could modify in some way the biological time structure of the neoplastic plasma cells. Successively, during relapse, there is a progressive return to circadian patterns of sLDH and sTK similar to those preceding the remission, as well as it occurs regarding the enzyme phosphoexoseisomerase [5] and p2-microglobulin [2].…”

Fluoride metabolism in smokers and non-smokers following enflurane anaesthesia

“…21 Serum concentrations of b 2 -microglobulin are also in¯uenced by immunological and stress reactions, and infections, because of the predominant production in lymphocytes. In our study, a possible in¯uence of diurnal variation in serum b 2microglobulin concentrations, with peak values in the morning, 22 was minimized by sampling at the same time each morning. The urine markers were determined from spot samples and normalized to urinary creatinine.…”

Circadian rhythm of serum erythropoietin in multiple myeloma

“…Several variables have been investigated from a chronobiological circadian point of view in MM [7,8], and this study is a further contribution in this field.…”

“…Moreover, renal failure, and not MM, seems to be responsible for the loss in EPO circadian rhythm. The reduced amplitude, with constant daily serum levels, represents, from a chronobiological point of view, a compensatory mechanism: constant levels of any biological active substance have the same effectiveness at higher, but fluctuating, levels [7].…”