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G Liossis

Publications and source records attributed to G Liossis.

4 recordsLinked to original sources

Effect of fresh frozen plasma and gammaglobulin on humoral immunity in neonatal sepsis.

Fresh frozen plasma and intravenous immunoglobulin are used as prophylaxis against, and for the treatment of, neonatal infection. It is assumed that any beneficial effect is mediated through the humoral immune factors contained in each preparation. The effect of fresh frozen plasma and intravenous immunoglobulin on humoral immune markers (immunoglobulins and IgG subclasses, complement components and activation products, and C reactive protein) was investigated over a 24 hour period after their randomised administration to 67 infants with suspected infection. Thirty infants without suspicion of infection were studied as controls. Compared with control infants, infants with suspected infection had increased concentrations of C reactive protein, reduced concentrations of fibronectin, and increased concentrations of the complement activation marker C3d, but similar concentrations of IgG, IgG subclasses, IgA, and IgM. After intravenous immunoglobulin treatment (500 mg/kg) concentrations of total IgG and all IgG subclasses increased, as did IgA and complement component C4. Concentrations of C reactive protein decreased after intravenous immunoglobulin treatment and were significantly lower than baseline after 24 hours. In contrast, no change in IgG or IgG subclass concentrations occurred after fresh frozen plasma administration. At 24 hours after fresh frozen plasma administration, concentrations of IgA, IgM, and C4 were significantly higher than baseline and serum IgA was significantly higher than in infants tested 24 hours after intravenous immunoglobulin treatment. These results confirm the rational basis for intravenous immunoglobulin treatment but question the value of fresh frozen plasma, particularly in the light of its attendant problems as an untreated blood product.

Antibody Formation↗

Complement activation in neonatal infection.

To investigate the usefulness of indices of complement activation in the diagnosis of infections in the neonatal period, activation products C4d, Ba, and C3d were measured in 42 babies with a putative diagnosis of infection based on clinical/laboratory criteria, and compared with conventional clinical and haematological criteria of infection and with C reactive protein. The diagnosis of sepsis was confirmed by culture and identification of organisms in 17. Fourteen babies in whom infection was not suspected formed the control group. In babies with proved infection, concentrations of the fragments C4d, Ba, and C3d were higher than in babies with suspected infection in whom microbiological tests were negative, and concentrations of Ba and C3d were higher than in controls. C reactive protein and the platelet count were not significantly different in babies with proved infection and those with negative microbiological tests, but in the latter, C reactive protein concentrations were higher than in controls. Of the indices studied, high concentrations of Ba predicted microbiologically proved infection with the highest sensitivity (47.1%) and specificity (92.0%). Ba thus seems to be useful as an early indicator of infection in the neonatal period.

Analysis of Variance↗

Red cell phosphate metabolism in full-term neonates.

The effects of hypoxia and feeding on red cell inorganic phosphate (Pi) concentrations were studied in neonates. Although hypoxia caused a rise in extracellular Pi, the intracellular concentration of this ion did not change in comparison to control infants of the same age (first 24 h). As a result of these changes, the distribution of phosphate ions across the erythrocyte membrane was significantly lower in the hypoxic infants than in the controls. In the hypoxic infants, adenosine triphosphate (ATP) levels in the red cells were found significantly lower than in controls, while the 2,3-diphosphoglycerate (2,3-DPG) levels were raised. In breast-fed 2 or 3-day-old neonates, both plasma and red cell Pi were found to be increased but to different degrees, affecting therefore the molar Pi distribution, which was lower than in the controls of the first day. In these infants, ATP was lower and 2,3-DPG higher than in the controls of the first day of life. These findings suggest that intracellular phosphate metabolism in neonates does not follow extracellular phosphate changes. Further investigation is needed to elucidate the controlling factors.

2,3-Diphosphoglycerate↗