Neutrophil and monocyte activation in chronic kidney disease patients under hemodialysis and its relationship with resistance to recombinant human erythropoietin and to the hemodialysis procedure

The aim of the present work was to further clarify leukocyte activation due to hemodialysis (HD) procedures and to investigate its relationship with recombinant human erythropoietin resistance. Therefore, we studied the expression of CXCR1 and CD11b on neutrophils, as well as the monocyte expression of CD11b, HLA‐DR, and CD14. We studied 34 chronic kidney disease (CKD) patients under HD and recombinant human erythropoietin treatment (26 responders and 8 nonresponders to recombinant human erythropoietin therapy). All CKD patients' blood samples were collected before and immediately after the HD procedure. Eighteen healthy individuals (blood donors) were also studied as a control group. Hematological data, neutrophil (CD11b and CXCR1), and monocyte (CD11b, HLA‐DR, and CD14) cell surface markers were measured in all patients (before and after the HD procedure) and controls. When compared with the controls, CKD patients presented a significant decrease in CXCR1 neutrophil expression, and in CD14 monocyte expression, accompanied by a significant increase in HLA‐DR monocyte expression. When comparing the 2 groups of patients, we found that nonresponders showed an additional decrease in CXCR1 neutrophil expression. After the HD procedure, a statistically significant increase in CD14 and CD11b monocyte surface markers and a decrease in CXCR1 neutrophil expression and in HLA‐DR monocyte expression was found. These data further strengthen our previous studies, showing that neutrophils and monocytes are activated in CKD patients, particularly in nonresponder patients. Moreover, this activation is due, at least in part, to the HD procedure, although we should not exclude that it can also be due to the enhanced inflammatory process observed in nonresponder patients.     

STABILITY OF WHOLE, FILLETED, AND MINCED TROUT (SALMO IRIDEUS GIBB) DURING FROZEN STORAGE

In order to determine the behavior of trout (Salmo irideus Gibb) muscle in frozen storage, five lots (whole, fillets, and minces obtained by extrusion, “mincer” and “cutter”) were made and stored at -20⁰C for one year. During this period the mince, mainly the one made with “cutter”, was more denaturated than the whole trout and fillets. The highest rate of insolubilization was reached by 255 days of storage (45% of soluble protein in minces and 60% in fillets and whole fish). Also a similar difference was noticed in the cooking drip. The variations of protein solubility do not thoroughly explain the changes in objective texture observed up to 30–75 days of storage. So, other parameters may be connected with these changes. On the other hand, after 165 days, the rancidity increase measured by the TBA value is high, especially in the mince although rancid flavor was detected at 120 days of storage.