Addition of L-carnitine to additive solution-suspended red cells stored at 4 degrees C reduces in vitro hemolysis and improves in vivo viability

BACKGROUND: The role of L-carnitine (LC) as the requisite carrier of long-chain fatty acids into mitochondria is well established. Human red cells (RBCs), which lack mitochondria, possess a substantial amount of LC and its esters. In addition, carnitine palmitoyl transferase, an enzyme that catalyzes the reversible transfer of the acyl moiety from acyl-coenzyme A to LC is found in RBCs. It has recently been shown that LC and carnitine palmitoyl transferase play a major role in modulating the pathway for the turnover of membrane phospholipid fatty acids in intact human RBCs, and that LC improved the membrane stability of RBCs subjected to high shear stress. RBC membrane lesions occur during storage at 4 degrees C; this study investigated whether the addition of LC (5 mM) to a standard RBC preservative solution (AS-3) affected cellular integrity with 42 days' storage. STUDY DESIGN AND METHODS: A paired (n = 10) crossover design was used for RBCs stored in AS-3 with and without LC. Both in vitro RBC properties reflective of metabolic and membrane integrity and in vivo measures of cell viability (24-hour percentage of recovery and circulating lifespan) were measured at the end of the storage. In addition, the turnover of membrane phospholipid and long-chain acylcarnitine fatty acids and the carnitine content of control and LC-stored RBCs were measured. RESULTS: It was shown that LC was irreversibly taken up by RBCs during storage, with a fourfold increase at 42 days. Furthermore, as found by the use of radiolabeled palmitate, the stored RBCs were capable of generating long-chain acylcarnitine. The uptake of LC during storage was associated with less hemolysis and higher RBC ATP levels and by a significantly greater in vivo viability for LC-stored RBCs than for control-stored RBCs: a mean 24-hour percentage of recovery of 83.9 +/? 5.0 vs. 80.1 +/? 6.0 percent and a mean lifespan of 96 +/? 11 vs. 86 +/? 14 days, respectively (p < 0.05). CONCLUSION: A beneficial effect of the addition of LC to RBCs stored at 4 degrees C was evident. This effect may be related to both biophysical and metabolic actions on the cell membrane.     

Negative ANA-IIF in SLE patients: what is beyond?

Clinical Rheumatology - The antinuclear antibody (ANA) test has high sensitivity in diagnosing and classifying systemic lupus erythematosus (SLE). To describe the immunological pattern of SLE...     

Restriction of cell lysis by homologous complement: II. Protection of erythrocytes against lysis by newly activated complement

Our previous work revealed that homologous complement (C) was ineffective in lysing antibody-sensitized erythrocytes (EA) even at high concentrations. It was also shown that activation of complement on homologous EA resulted in the binding of C9 and the formation of EA bearing complement proteins C1 through C9 (EAC1-9), yet few hemolytic sites were formed. Instead, as shown here, the formation of homologous EAC1-9 caused the cells to become resistant to lysis even by heterologous complement during a second incubation. In contrast, when homologous EAC1-8 were produced by incubating EA with C9-depleted serum, such intermediates were not protected against lysis by heterologous complement during a second incubation. Furthermore, homologous C9 on EAC1-9 was able to reduce the hemolytic efficiency of heterologous complement without blocking C activation and the formation of new C5b-9 complexes. Protection was not modified when homologous EAC1-9 were produced in one step, by incubation of EA with serum, or sequentially by adding C9 to EAC1-8. The minimum number of 9-sites required to confer a protective effect on EAC1-9 was less than 200 per cell. Thus, in addition to its known effect in heterologous cell killing, homologous C9 is capable of protecting homologous cells against inadvertent complement lysis.     

Recombinant human interleukin-3 stimulation of hematopoiesis in humans: loss of responsiveness with differentiation in the neutrophilic myeloid series

Recombinant human (rh) interleukin-3 (IL-3) stimulated the proliferation and differentiation of erythroid, granulocyte, macrophage, eosinophil (Eo), and mixed colonies as well as megakaryocytes from human bone marrow cells. rh IL-3 was a weaker stimulus than rh granulocyte-macrophage colony-stimulating factor (GM- CSF) for day 14 myeloid cell colonies. At day 7 of incubation, rh IL-3 stimulated a few G, M, and Eo clusters but no colonies. This loss of responsiveness of myeloid cells to rh IL-3 was accentuated with further differentiation of the cells. rh IL-3 stimulated very few or no clones after five-day incubation with enriched promyelocytes and myelocytes, whereas rh GM-CSF was an efficient stimulus. Responsiveness to rh IL-3 was completely lost in postmitotic mature neutrophils. Incubation of these cells with rh IL-3 did not result in enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) of tumor cells or superoxide anion production after stimulation with formyl-methyl-leucyl-phenylalanine (FMLP), although they could be stimulated by rh GM-CSF. In addition, preincubation of neutrophils with different concentrations of rh IL-3 failed to increase or decrease their response to rh GM-CSF. In contrast to neutrophils, mature Eos could be stimulated by rh IL-3 to kill antibody-coated tumor cells. These results show that cells of the neutrophilic myeloid series lose their responsiveness to h IL-3 as they differentiate and suggest that although h IL-3 may be an important therapeutic agent to use for hematopoietic regeneration in vivo, the lack of stimulation of mature neutrophil function makes it an unlikely sole candidate as adjunct therapy for treatment of infectious diseases.     

Combination of ECMO and cytokine adsorption therapy for severe sepsis with cardiogenic shock and ARDS due to Panton–Valentine leukocidin—positive <Emphasis Type="Italic">Staphylococcus aureus</Emphasis> pneumonia and H1N1

Sepsis-induced cardiogenic shock in combination with severe acute respiratory failure represents a life-threatening combination that is often refractory to the conventional methods of treatment. We describe the case of a 33-year-old patient who developed acute cardiovascular collapse and ARDS secondary to superinfection of Panton–Valentine leukocidin—positive Staphylococcus aureus and H1N1 pneumonia who underwent successful combination therapy for severe sepsis-related cardiomyopathy and respiratory failure using extracorporeal membrane oxygenation and cytokine adsorption therapy.     

249 TP53 mutation has high prevalence and is correlated with larger and poorly differentiated HCC in Brazilian patients

Background  

Ser-249 TP53 mutation (249^Ser) is a molecular evidence for aflatoxin-related carcinogenesis in Hepatocellular Carcinoma (HCC) and it is frequent in some African and Asian regions, but it is unusual in Western countries. HBV has been claimed to add a synergic effect on genesis of this particular mutation with aflatoxin. The aim of this study was to investigate the frequency of 249^Ser mutation in HCC from patients in Brazil.     

Utilisation of psychotropic drugs in patients of the long stay ward

A survey of the prescribing of psychotropic drugs was carried out at the Psychiatric Hospital of Bahrain. This retrospective study on 60 inpatients of the Long Stay Ward revealed a man:woman ratio of 2.7. 91% of the men and 88% of the women were over 40 years old. 44 of the 60 patients had a diagnosis of schizophrenia, the rest had dementia, depression, schizoaffective disorders, drug-induced psychosis, general paralysis or Huntington's chorea. 95% of patients received antipsychotic drugs. Thioridazine was the most common drug followed by chlorpromazine. The mean number of drugs/patient was 1.7, with 41.7% of patients receiving only 1 drug. Tardive dyskinesia was observed in 11 patients and 9 experienced varying degrees of tremor. The findings confirm that psychiatric illness treated by psychiatrists need not lead to polypharmacy. As a consequence, its treatment may be less likely to result in adverse reactions than when patients are treated by general practitioners.