Éditeur(s) : HAL CCSD
Résumé : ABSTRACT Infectious complications are a leading cause of morbidity and mortality in patients with sickle cell disease. The exact reasons of the propensity of sickle cell patients to infection are not clear and are matter of debate. Besides, there is a striking variability of the clinical course of the disease between patients. This drew many scientists' attention. Genetic factors have been investigated as potential factor risks for infection in sickle cell patients, for example: HLA system; genes encoding Fc Human Immunoglobulin G receptor IIA, mannose-binding protein, and myeloperoxidase. Associations have been found, but all scientists agree that investigations have to be furthered. We investigated an association between HLA DRB1 and DQB1 polymorphism and infectious complications in sickle cell patients. Genotype frequencies were different between cases and controls for DRB1 locus. Indeed, HLA-DRB1*11 frequency was significantly higher in patients without infections than in patients with infections (χ² = 5.02; p = 0.025).
https://hal.archives-ouvertes.fr/hal-00387082

hal-00387082
https://hal.archives-ouvertes.fr/hal-00387082
https://hal.archives-ouvertes.fr/hal-00387082/document
https://hal.archives-ouvertes.fr/hal-00387082/file/MO_JOANNES_et_al_HLA_and_SCD.pdf

Éditeur(s) : HAL CCSD IOS Press
Résumé : International audience
Because of the metabolic changes induced by a physical activity, the hemorheological properties of patients with sickle cell anemia could be further impaired and increase the risks for vaso-occlusive complications. However, few studies suggest that moderate physical activity could be beneficial rather than harmful in patients with sickle cell anemia (SCA). However, the definition of what can be considered as a moderate physical activity in SCA patients is imprecise. The present study tested the effects of a short incremental cycling exercise test conducted until the first ventilatory threshold on different biomarkers. Hematological and hemorheological parameters were compared between 8 patients with SCA and 13 healthy subjects (CONT) before, immediately after the end of the exercise and at 12, 36 and 60 hours after the exercise. We observed no significant hematological or hemorheological alteration induced by the exercise in the two groups. However, the exercise resulted in a delayed improvement of the red blood cell disaggregation threshold at 36 and 60 hrs after exercise in the SCA group which was paralleled to the decrease in the platelet count in this group. The present study suggests that such an exercise might be beneficial for microcirculatory blood flow.
ISSN: 1386-0291

hal-01137567
https://hal.univ-antilles.fr/hal-01137567

Éditeur(s) : HAL CCSD
Résumé : ABSTRACT Infectious complications are a leading cause of morbidity and mortality in patients with sickle cell disease. Several mechanisms are supposed to contribute to this susceptibility. The exact reasons of the propensity of sickle cell patients to infection are not clear and are still matter of debate. Interferon gamma is a key cytokine involved namely in the defence against intracellular pathogens. We investigated a possible association of +874 T/A IFNγ polymorphism and infectious complications in sickle cell patients. Seventy-two sickle cell patients were typed for +874 T/A IFNγ polymorphism. Genotype frequencies were different between cases and controls. Indeed, T allele frequency was significantly higher in patients with infections than in patients without infections (χ² = 6.23 ; p = 0.013). Our results suggest that +874 T/A IFNγ polymorphism is associated with infectious complications in sickle cell patients. The T allele could be involved in infections in sickle cell patients.
https://hal.archives-ouvertes.fr/hal-00387081

hal-00387081
https://hal.archives-ouvertes.fr/hal-00387081
https://hal.archives-ouvertes.fr/hal-00387081/document
https://hal.archives-ouvertes.fr/hal-00387081/file/MO_Joannes_et_al._IFNG_polymorphism_and_sickle_cell_disease.pdf

Éditeur(s) : HAL CCSD IOS Press
Résumé : International audience
Purpose: The aim of this study was to clarify whether exercising in a tropical climate induces blood rheology alterations despite ad libitum hydration. Methods: Hematological, biochemical and hemorheological changes were investigated in young healthy adults (N = 9 men, 20.7 ± 0.8 yrs) after a 10-km race in hot and humid conditions. Subjects' maximal aerobic abilities were tested using a maximal ramp exercise. Blood was sampled at rest (T R), at the end of the race (T Ex), and after 24 hours of recovery (T 24). Ad libitum hydra-tion was allowed during the race. Blood viscosity (b), red blood cell deformability (EI), aggregation (AI) and disaggregation shear rate (␥) were measured. Results: Hematocrit, hemoglobin and plasma concentration of chlorine, sodium and potassium did not change in response to exercise. No functional consequence was observed on RBC deformability since EI remained unchanged. Percentages of echinocytes, schizocytes and stomatocytes remained in the subclinical range at all times. AI, µ and ßb did not present change. Conclusion: Running exercise in tropical climate with ad libitum hydration does not alter the main rheological properties of blood.
ISSN: 1386-0291

hal-01163975
https://hal.univ-antilles.fr/hal-01163975
DOI : 10.3233/CH-2011-1388