Erythrocyte Membrane Sialic Acid in New-Born Infants

Abstract

Erythrocyte surface sialic acid was measured in 94 full-term new-born infants and in 20 premature infants of different ages, varying from 1 to 16 post-natal days. After the first 3 days of life, the amount of sialic acid, both per cell and per gramme of haemoglobin, was rapidly reduced to 70–80% of the initial value; these lower levels were maintained on the following days. The decrease observed on the 4th day may represent an expression of the mechanism by which a large amount of fetal red blood cells is eliminated from the circulation during the same period. Therefore, the relationship between sialic acid decrement and red cell sequestration exists also in fetal erythrocytes, and this may contribute to clarify the exact role of sialic acid in red cell survival time.

Red Blood Cell Stiffness and Adhesion Are Species-Specific Properties Strongly Affected by Temperature and Medium Changes in Single Cell Force Spectroscopy

“…This can be attributed to a larger contact area since Ea decreased in parallel [43]. Concerning hydrophilicity as another cause for speciesspecificity, we found congruence between the measured detachment work at RT and the reported sialic acid concentration of the tested species [24,25,28,29,32]. Both parameters show the same ranking: horse/human fetus/camel > human adult > chicken (due to the different methods used in the reports, the sialic acid concentration from horse, human fetus, and camel RBC cannot be further discriminated).…”

“…Moreover, we attempted to assess the feasibility of SCFS under largely physiological conditions by suspending RBCs in autologous plasma. 28.5 ± 6.6 [19] 0.618 (0.612/0.623) [19] --none Human fetus 11% wider diameter than adult [20] 4.84 ± 0.89 [21] higher rigidity index [21], lower shear elastic modulus [22] comparable [23] increased [24,25] none, 21% bigger cell volume [20] Horse biconcave diameter 5.7 µm 55.9 ± 13.4 [19] 0.679 (0.590/0.878) [19] deficient in band 4.2 and band 6 [26,27] increased [28,29] none Camel elliptic dimension 7 × 4 µm [30] none [31] n.a.…”

Evaluation of some tumor markers, acute phase proteins, sialic acid and lipid bound sialic acid before and after chemotherapy in stomach cancer

“…Many researchers determined that total and lipid bounded sialic acid levels increased in different cancer types (27,28). It is known that the sialic acid is necessary for cell adhesion and carries out the electrostatic impulse in thrombocyte, cancer cells and erythrocytes via the negative charge (29).…”