Éditeur(s) : HAL CCSD IOS Press
Résumé : International audience
Little is known about the impact of blood rheology on the occurrence of retinopathy in sickle cell disease (SCD). Fifty-nine adult SCD patients in steady-state condition participated to the study: 32 with homozygous SCD (sickle cell anemia; SCA) and 27 with sickle cell hemoglobin-C disease (SCC). The patients underwent retinal examination and were categorized according to the classification of Goldberg: 1) no retinopathy (group 1), 2) non-proliferative or proliferative stage I-II retinopathy (group 2) and 3) proliferative stage III-IV-V retinopathy (group 3). Hematological and hemorheological (whole blood viscosity, RBC deformability and aggregation properties) measurements were performed for each patient. In the whole SCD group (SCA + SCC patients) and in SCC patients, the group 3 had higher platelets count than group 2 but the difference between group 3 and group 1 did not reach statistical significance. No difference was observed for the other parameters between the three groups. SCC patients from the group 3 exhibited higher whole blood viscosity than SCC patients from the group 1. No significant difference was observed between the three groups in SCA patients. This study revealed that severe sickle proliferative retinopathy is associated with blood hyperviscosity in SCC patients but not in SCA patients.
ISSN: 1386-0291

inserm-00849032
http://www.hal.inserm.fr/inserm-00849032
http://www.hal.inserm.fr/inserm-00849032/document
http://www.hal.inserm.fr/inserm-00849032/file/inserm-00849032.pdf
DOI : 10.3233/CH-2012-1622

Éditeur(s) : HAL CCSD Ferrata Storti Foundation
Résumé : International audience
The aim of the study was to determine the factors associated with resting and exercise-induced hemoglobin oxygen desaturation. The well-established six-minute walk test was conducted in 107 sickle cell children (50 with sickle hemoglobin C disease and 57 with sickle cell anemia) at steady state. Hemoglobin oxygen saturation was measured before and immediately after the six-minute walk test. Blood samples were obtained on the same day to measure hematologic and hemorheological parameters. Exercise-induced hemoglobin oxygen desaturation was defined as a drop in hemoglobin oxygen saturation of 3% or more at the end of the six-minute walk test compared to resting levels. No children with sickle hemoglobin C disease, but approximately 50% of children with sickle cell anemia showed mild or moderate oxygen desaturation at rest, which was independently associated with the percentage of reticulocytes. Exercise-induced hemoglobin oxygen desaturation was observed in 18% of children with sickle hemoglobin C disease and 34% of children with sickle cell anemia, and was independently associated with the six-minute walk test, acute chest syndrome rate and the strength of red blood cell aggregates in children with sickle cell anemia. No association was found in children with sickle hemoglobin C disease between exercise-induced hemoglobin oxygen desaturation and the measured parameters. Hemoglobin oxygen desaturation at rest was common in children with sickle cell anemia but not in children with sickle hemoglobin C disease, and was mainly associated with greater hemolysis. Physiological strain during exercise and red blood cell aggregation properties may predict the occurrence of exercise-induced hemoglobin oxygen desaturation in children with sickle cell anemia.
ISSN: 0390-6078

inserm-00838989
http://www.hal.inserm.fr/inserm-00838989
http://www.hal.inserm.fr/inserm-00838989/document
http://www.hal.inserm.fr/inserm-00838989/file/Waltz_et_al._Ferrata_Storti_Foundation.pdf
DOI : 10.3324/haematol.2013.083576

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
MR and MDHD contributed equally to this work. Summary Painful vaso-occlusive crisis, a hallmark of sickle cell anaemia, results from complex, incompletely understood mechanisms. Red blood cell (RBC) damage caused by continuous endogenous and exogenous oxidative stress may precipitate the occurrence of vaso-occlusive crises. In order to gain insight into the relevance of oxidative stress in vaso-occlusive crisis occurrence , we prospectively compared the expression levels of various oxidative markers in 32 adults with sickle cell anaemia during vaso-occlusive crisis and steady-state conditions. Compared to steady-state condition, plasma levels of free haem, advanced oxidation protein products and myeloperoxi-dase, RBC caspase-3 activity, as well as the concentrations of total, neutrophil-and RBC-derived microparticles were increased during vaso-occlusive crises, whereas the reduced glutathione content was decreased in RBCs. In addition, natural anti-band 3 autoantibodies levels decreased during crisis and were negatively correlated with the rise in plasma advanced oxidation protein products and RBC caspase-3 activity. These data showed an exacerbation of the oxidative stress during vaso-occlusive crises in sickle cell anaemia patients and strongly suggest that the higher concentration of harmful circulating RBC-derived microparticles and the reduced anti-band 3 autoantibodies levels may be both related to the recruitment of oxidized band 3 into membrane aggregates.
ISSN: 0007-1048

inserm-01476067
http://www.hal.inserm.fr/inserm-01476067
http://www.hal.inserm.fr/inserm-01476067/document
http://www.hal.inserm.fr/inserm-01476067/file/2016%2C%20Hierso%20-%20Exacerbation%20of%20oxidative%20stress%20during%20sickle%20vaso-occlusive%20crisis.pdf
DOI : 10.1111/bjh.14476

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Hemorheological abnormalities have been well characterized in sickle cell disease (SCD) and seem to modulate the clinical severity [1]. For instance, increased blood viscosity raises the risk for frequent vaso-occlusive crisis (VOC) and increased red blood cell (RBC) aggregates robustness (i.e., RBC disaggregation threshold) enhances the risks for acute chest syndrome (ACS) [2]. Moreover, patients with the most rigid RBCs are characterized by high hemolytic rate, which increases the risks to develop leg ulcers or glomerulopathy [3]. However, except few studies supporting an effect of alpha-thalassemia and oxidative stress [1] on RBC rheological properties of SCD patients, very few experiments focused on the genetic and cellular factors modulating blood rheology in this disease.
ISSN: 1079-9796

hal-01263890
https://hal.archives-ouvertes.fr/hal-01263890
https://hal.archives-ouvertes.fr/hal-01263890/document
https://hal.archives-ouvertes.fr/hal-01263890/file/Ferdinand%20et%20al.%20eNOS%20and%20RBC%20rheology%20in%20SCD_BCMD.pdf
PUBMED : 26142331

Éditeur(s) : HAL CCSD IOS Press
Résumé : International audience
The hematocrit-to-viscosity ratio (HVR) has been widely used has an estimate of red blood cell (RBC) oxygen transport effectiveness into the microvasculature or as an oxygen delivery index. However, no study investigated the possibility of HVR to truly reflect RBC oxygen transport effectiveness or to be an oxygen delivery index. We measured blood viscosity at high shear rate (225 s-1), hematocrit, HVR, as well as the microvascular oxyhemoglobin saturation (TOI; tissue oxygen index) by spatial resolved near-infrared spectroscopy (NIRS) at cerebral and muscle levels in three population known to have various degrees of hemorheological abnormalities: healthy subjects (AA), patients with sickle cell SC disease (SC) characterized by moderate anemia and patients with sickle cell anemia (SS) marked by severe anemia. At both the cerebral and muscle level, HVR was positively correlated with TOI (r = 0.28; p = 0.03 and r = 0.38; p = 0.003, at the cerebral and muscle level, respectively). These findings suggest that HVR probably play a key role in blood flow and hemodynamic regulation in the microvasculature, hence modulating the amount of oxygen available for tissues. Nevertheless, the strengths of the associations are weak (R2 < 0.50), suggesting that other determinants modulate microvascular blood flow and oxygenation, such as vascular geometry and vasomotor reserve.
ISSN: 1386-0291

inserm-01081701
http://www.hal.inserm.fr/inserm-01081701
http://www.hal.inserm.fr/inserm-01081701/document
http://www.hal.inserm.fr/inserm-01081701/file/2013%2C%20Waltz%20-%20Is%20there%20a%20relationship%20between%20the%20hematocrit-to-viscosity%20ratio%20and%20microvascular%20oxygenation%20in%20brain%20and%20muscle.pdf
PUBMED : 23719422

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
Background: Squamous cell carcinoma (SCC) is considered the most frequent skin cancer in black people. Its incidence is not known in the Afro-Caribbean population.Objective: To assess the incidence of SCC in Guadeloupe, the largest island of the Lesser Antilles (405 000 inhabitants, mostly black people of African and European descent). The second objective was to characterize clinical and histological patterns of SCC occurring in the Afro-Caribbean community.Methods: This retrospective study was conducted over an 11-year period (2000-2010). Data regarding 723 histological confirmed cases of SCC identified using the three Guadeloupean pathology laboratories computerized databases were retrieved from the records of 551 patients. Private practice dermatologists and general practitioners were contacted to obtain any missing data. Results: The annual age-adjusted incidence of SCC was 15 per 100.000 residents in Guadeloupe. In the Afro-Caribbean community, SCC had a greater size (i.e.: 2.8±2.8 cm versus 1.5±1.0 cm, p<0.001), was more often located on the anogenital area (i.e. :48/79-60.8% versus 14/320-4.4%, p<0.001) in association with an underlying dermatosis due to HPV infection (15/71- 21.1% versus 3/366, 0.8%, p<0.001) and led more frequently to metastasis (13/84-15.5% versus 10/366-2.7%, p<0.001) and/or fatal evolution (11/83-13.3% versus 7/365-1.9%, p<0.001). Conclusions: The results of this original study, which first estimated the incidence of SCC in West Indies, suggest that anogenital examination should be routinely performed in skin cancer screening of Afro-Caribbean people in order to detect the presence of SCC at an early stage.
ISSN: 0926-9959

inserm-01513116
http://www.hal.inserm.fr/inserm-01513116
http://www.hal.inserm.fr/inserm-01513116/document
http://www.hal.inserm.fr/inserm-01513116/file/2017%2C%20Cordel%20-%20Squamous%20cell%20carcinoma%20in%20the%20Afro-Caribbean%20community.pdf
http://www.hal.inserm.fr/inserm-01513116/file/CordeletalJ%20Eur%20Acad%20Dermatol%20Venereol2017.pdf

Éditeur(s) : HAL CCSD Ferrata Storti Foundation
Résumé : International audience
Lionnet et al. recently reported a high prevalence of retinopathy (RET) and otologic disorders (OTD) in patients with sickle cell-hemoglobin C disease (SC), while a significant number of patients had renal diseases (mainly glomerulopathy; GLO) and osteonecrosis (OST). The pathophysiological processes of these complications in SC are not well defined, although blood hyperviscosity has been suspected, but never tested to the best of our knowledge, as responsible for several chronic complications in SC disease1,2. The aim of this study was to analyze the associations between hematological and hemorheological parameters and chronic complications in adult SC patients.
ISSN: 0390-6078

inserm-01081709
http://www.hal.inserm.fr/inserm-01081709
http://www.hal.inserm.fr/inserm-01081709/document
http://www.hal.inserm.fr/inserm-01081709/file/2014%2C%20Lemonne%20-%20Impaired%20blood%20rheology%20plays%20a%20role%20in%20the%20chronic%20disorders%20associated%20with%20sickle%20cell-hemoglobin%20C%20disease.pdf
PUBMED : 24633868

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
Leg ulcer is a disabling complication in patients with sickle cell anemia (SCA) but the exact pathophysiological mechanisms are unknown. The aim of this study was to identify the hematological and hemorheological alterations associated with recurrent leg ulcers. Sixty-two SCA patients who never experienced leg ulcers (ULC-) and 13 SCA patients with a positive history of recurrent leg ulcers (ULC+) - but with no leg ulcers at the time of the study - were recruited. All patients were in steady state condition. Blood was sampled to perform hematological, biochemical (hemolytic markers) and hemorheological analyses (blood viscosity, red blood cell deformability and aggregation properties). The hematocrit-to-viscosity ratio (HVR), which reflects the red blood cell oxygen transport efficiency, was calculated for each subject. Patients from the ULC+ group were older than patients from the ULC- group. Anemia (red blood cell count, hematocrit and hemoglobin levels) was more pronounced in the ULC+ group. Lactate dehydrogenase level was higher in the ULC+ group than in the ULC- group. Neither blood viscosity, nor RBC aggregation properties differed between the two groups. HVR was lower and RBC deformability tended to be reduced in the ULC+ group. Our study confirmed increased hemolytic rate and anemia in SCA patients with leg ulcers recurrence. Furthermore, our data suggest that although systemic blood viscosity is not a major factor involved in the pathophysiology of this complication, decreased red blood cell oxygen transport efficiency (i.e., low hematocrit/viscosity ratio) may play a role.
ISSN: 1932-6203

inserm-00922105
http://www.hal.inserm.fr/inserm-00922105
http://www.hal.inserm.fr/inserm-00922105/document
http://www.hal.inserm.fr/inserm-00922105/file/2013_Connes_-_Decreased_Hematocrit.pdf
DOI : 10.1371/journal.pone.0079680

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
The six-minute walk test is a well-established submaximal exercise reflecting the functional status and the clinical severity of sickle cell patients. The aim of the present cross-sectional study was to investigate the biological determinants of the six-minute walk test performance in children with sickle cell anemia. Hematological and hemorheological parameters, pulmonary function and the six-minute walk test performance were determined in 42 children with sickle cell anemia at steady state. The performance during the six-minute walk test was normalized for age, sex and height and expressed as percentage of the predicted six-minute walk distance. We showed that a high level of anemia, a low fetal hemoglobin expression and low red blood cell deformability were independent predictors of a low six-minute walk test performance. This study describes for the first time the impact of blood rheology in the six-minute walk test performance in children with sickle cell anemia.
ISSN: 1932-6203

inserm-00922110
http://www.hal.inserm.fr/inserm-00922110
http://www.hal.inserm.fr/inserm-00922110/document
http://www.hal.inserm.fr/inserm-00922110/file/2013_Waltz_-_Hematological_and_hemorheological_determinants_6_minutes.pdf
DOI : 10.1371/journal.pone.0077830

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
A retrospective cohort study was conducted on 1541 HIV-infected patients to determine variables associated with the incidence of herpes zoster. A single failure Cox model showed that herpes zoster incidence increased following the first 6 months of antiretroviral treatment adjusted hazard ratio (AHR)=5 (95%CI=2.6-9.2), P<0.001; in the >60 years age group AHR=2 (95%CI=1-4), P=0.04; in patients in the top CD8 quartile AHR=2.1 (95%CI=1.3-3.6), P<0.001; and in patients previously reported to use crack cocaine AHR=5.9, (95%CI=1.4-25), P=0.02. Herpes zoster incidence increased in patients with CD4 counts<500 per mm(3) and gradually declined since 1992-1996, with AHR=0.3 (95%CI=0.2-0.5), P<0.001 for the 1997-2002 period and AHR=0.24 (95%CI=0.14-0.4), P<0.001 for the 2002-2008 period. Contrary to what has been described elsewhere, there was no specific effect of protease inhibitors on herpes zoster incidence. The present study is the first to suggest that crack cocaine is associated with an increased incidence of herpes zoster. The neurological or immunological effects of crack are discussed.
ISSN: 1932-6203

inserm-00921158
http://www.hal.inserm.fr/inserm-00921158
http://www.hal.inserm.fr/inserm-00921158/document
http://www.hal.inserm.fr/inserm-00921158/file/2013_Nacher_-_Predictive_factorssur herpes_zoster.pdf
DOI : 10.1371/journal.pone.0080187

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
ISSN: 0007-1048

hal-01668324
https://hal.univ-antilles.fr/hal-01668324
DOI : 10.1111/bjh.14064

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
Patients with sickle cell anemia (SCA) have usually lower diastolic, systolic and mean blood pressure (BP) than the general population. However, BP values ≥120/70 mmHg considerably increase the risk for acute and chronic complications in SCA. The aim of this study was to identify biological factors associated with relative hypertension in adults with SCA. We compared the hematological, lipid and hemolytic profiles, as well as blood viscosity, between SCA patients with normal BP (<120/70 mmHg, n = 54) and those with relative hypertension (BP≥120/70 mmHg, n = 43). Our results demonstrated that male gender (OR: 3.49; 95%CI 1.20 to 10.16, p<0.05), triglycerides (OR: 9.19; 95% CI 2.29 to 36.95, p<0.01), blood viscosity (OR: 1.35; 95% CI 1.01 to 1.81, p<0.05) and body mass index (OR: 1.37; 95% CI 1.14 to 1.64, p<0.01) were independent risks factors for relative hypertension in SCA. No association was found between the BP status and the positive history of painful vaso-occlusive crisis or acute chest syndrome. An association between triglycerides level and the occurrence of these two major acute complications was detected. Our study suggests that male gender, increased triglycerides level, BMI and blood viscosity could increase the risk for developing relative hypertension in SCA. In addition, our results support a role of moderately elevated triglycerides in the pathophysiology of vaso-occlusive events.
ISSN: 1932-6203

inserm-00838991
http://www.hal.inserm.fr/inserm-00838991
http://www.hal.inserm.fr/inserm-00838991/document
http://www.hal.inserm.fr/inserm-00838991/file/Lamarre_et_al._2013_PloS_ONE_.pdf
DOI : 10.1371/journal.pone.0066004

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
BACKGROUND: In Guadeloupe and Martinique, two French Overseas Departments, colorectal cancer (CRC) has become an essential public health issue. However, little is known about CRC characteristics and the p53 status in these populations, particularly in Guadeloupe, whereas certification of a cancer registry has been recently validated. METHODS: This was a descriptive retrospective study of 201 patients who, between 1995 and 2000, underwent surgery for CRC in the Guadeloupe Teaching Hospital (GlpeTH; 83 patients) and in the Martinique Teaching Hospital (MqueTH; 118 patients). The clinicopathological features and the p53 expression, evaluated with immunohistochemistry, were compared at the time of diagnosis. A relationship between these parameters and the p53 expression was also studied. Data were analysed, using the SPSS computer software version 17.0. RESULTS: No statistical difference was found between the two groups of patients regarding age (p = 0.60), percentage of young patients (<=50 years; p = 0.94)), sex (p = 0.47), histological type (p = 0.073) and tumour sites (p = 0.65), although the GlpeTH patients were diagnosed with more distal colon cancers (54.2%) than the Mque TH patients (47.4%). By contrast, a significant difference was found regarding the tumour grade (p < 0.0001), the pTNM stage (p = 0.045) and the pT stage (p < 0.0001). Regarding p53 expression, solely for the MqueTH patients, nuclear expression was associated with pTNM, the percentage of p53 negative tumours increasing with the progression of the pTNM stages (p = 0.029). CONCLUSIONS: For the first time, this study reveals discrepancies in clinicopathological features and in the p53 status between the two groups of patients. The GlpeTH patients were diagnosed with more moderated CRCs but with few CRCs at pTNM IV stage. By contrast, the MqueTH patients were diagnosed with more differentiated tumours, but with many more CRCs at pTNM IV stage. This paradox may be due to differences in tumour location (distal vs proximal), multiplicity of the genetic profiles of patients, or patients getting treatment elsewhere. Although our study is limited due to its small size, it emphasizes the originality of our results.
ISSN: 1472-6890

inserm-00971313
http://www.hal.inserm.fr/inserm-00971313
http://www.hal.inserm.fr/inserm-00971313/document
http://www.hal.inserm.fr/inserm-00971313/file/1472-6890-14-12.pdf
DOI : 10.1186/1472-6890-14-12

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
It is unclear whether vascular function is affected similarly in children with sickle cell anaemia (SS) and children with sickle haemoglobin C (SC) disease. Therefore, we compared micro and macrovascular functions in healthy (AA) children, children with SS and SC disease, and assessed their association with physical activity. Participants (24 SS, 22 SC and 16 AA), were compared in terms of 1) thermal hyperaemic response (finger pad warming to 42 °C) measured by Laser Doppler techniques, 2) arterial stiffness determined by pulse wave velocity, 3) daily energy expenditure related to moderate and intense physical activities estimated by questionnaire and 4) fitness level, evaluated by the six-minute walk test. Response to heating differed between SS, SC and controls. Peripheral microvascular reactivity was lower and pulse wave velocity higher in SS compared to AA. SC had blunted microvascular reactivity in response to heating compared to AA but pulse wave velocity was not different within the two groups. Physical activity and fitness levels were markedly lower in sickle cell patients compared to healthy controls but no association was observed with vascular function. Microvasodilatory reserve is decreased in both SS and SC patients but only SS patients were also characterised by impaired macrovascular function.
ISSN: 1079-9796

hal-01496857
https://hal.archives-ouvertes.fr/hal-01496857
https://hal.archives-ouvertes.fr/hal-01496857/document
https://hal.archives-ouvertes.fr/hal-01496857/file/Mo%CC%88ckesch%20et%20al%20BCMD%20non%20apparent%20corrections%20final.pdf
DOI : 10.1016/j.bcmd.2017.02.001

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
ISSN: 1079-9796

hal-01679011
https://hal.univ-antilles.fr/hal-01679011
DOI : 10.1016/j.bcmd.2017.02.001

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
BACKGROUND/AIM: Although it has been hypothesized that muscle metabolism and fatigability could be impaired in sickle cell patients, no study has addressed this issue. METHODS: We compared muscle metabolism and function (muscle microvascular oxygenation, microvascular blood flow, muscle oxygen consumption and muscle microvascular oxygenation variability, which reflects vasomotion activity, maximal muscle force and local muscle fatigability) and the hemorheological profile at rest between 16 healthy subjects (AA), 20 sickle cell-hemoglobin C disease (SC) patients and 16 sickle cell anemia (SS) patients. RESULTS: Muscle microvascular oxygenation was reduced in SS patients compared to the SC and AA groups and this reduction was not related to hemorhelogical abnormalities. No difference was observed between the three groups for oxygen consumption and vasomotion activity. Muscle microvascular blood flow was higher in SS patients compared to the AA group, and tended to be higher compared to the SC group. Multivariate analysis revealed that muscle oxygen consumption was independently associated with muscle microvascular blood flow in the two sickle cell groups (SC and SS). Finally, despite reduced muscle force in sickle cell patients, their local muscle fatigability was similar to that of the healthy subjects. CONCLUSIONS: Sickle cell patients have normal resting muscle oxygen consumption and fatigability despite hemorheological alterations and, for SS patients only, reduced muscle microvascular oxygenation and increased microvascular blood flow. Two alternative mechanisms can be proposed for SS patients: 1) the increased muscle microvascular blood flow is a way to compensate for the lower muscle microvascular oxygenation to maintain muscle oxygen consumption to normal values or 2) the reduced microvascular oxygenation coupled with a normal resting muscle oxygen consumption could indicate that there is slight hypoxia within the muscle which is not sufficient to limit mitochondrial respiration but increases muscle microvascular blood flow.
ISSN: 1932-6203

inserm-00849035
http://www.hal.inserm.fr/inserm-00849035
http://www.hal.inserm.fr/inserm-00849035/document
http://www.hal.inserm.fr/inserm-00849035/file/2013_Waltz_-_Normal_muscle_oxygen_consumption_and_fatigability_in_sickle_cell_patients.pdf
DOI : 10.1371/journal.pone.0052471

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
ISSN: 1079-9796

hal-01679023
https://hal.univ-antilles.fr/hal-01679023
DOI : 10.1016/j.bcmd.2017.02.001

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
A recent study suggested that adenosine signaling pathway could promote hemolysis in patients with sickle cell anemia (SCA). This signaling pathway involves several gene coding enzymes for which variants have been described. In this study, we analyzed the genotype-phenotype relationships between functional polymorphisms or polymorphisms associated with altered expression of adenosine pathway genes, namely adenosine deaminase (ada; rs73598374), adenosine A2b receptor (adora2b; rs7208480), adenylyl cyclase6 (adcy6; rs3730071, rs3730070, rs7300155), and hemolytic rate in SCA patients. One hundred and fifty SCA patients were genotyped for adcy6, ada, and adora2b variants as well as alpha-globin gene, a genetic factor known to modulate hemolytic rate. Hematological and biochemical data were obtained at steady-state. Lactate dehydrogenase, aspartate aminotransferase, reticulocytes and total bilirubin were used to calculate a hemolytic index. Genotype-phenotype relationships were investigated using parametric tests and multivariate analysis. SCA patients carrying at least one allele of adcy6 rs3730070-G exhibited lower hemolytic rate than non-carriers in univariate analysis (p=0.006). The presence of adcy6 rs3730070-G variant was associated with a decreased hemolytic rate in adjusted model for age and alpha-thalassemia (p=0.032). Our results support a protective effect of adcy6 rs3730070-G variant on hemolysis in SCA patients.
ISSN: 1079-9796

hal-01668332
https://hal.univ-antilles.fr/hal-01668332
DOI : 10.1016/j.bcmd.2016.02.006

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
The present study investigated cerebral and muscle hemoglobin oxygen saturation (tissue oxygen index, TOI) in children with sickle cell anemia (SS), sickle cell hemoglobin C disease (SC) and healthy children (AA). TOI was measured by near-infrared spectroscopy (NIRS) and spectral analysis of the TOI variability was used to assess flowmotion and vasomotion. Arterial oxyhemoglobin saturation (SpO2), hemorheological and hematological parameters were also measured in SS and SC children. Both TOI were lower in SS compared to both AA and SC children, with SC exhibiting lower values than AA children. Cerebral vasomotion expressed in absolute values was enhanced in SS compared to AA and SC children. Muscle vasomotion did not differ between the three groups. Hematocrit, SpO2 and red blood cell deformability were positively associated with cerebral TOI in SS children. We demonstrated that 1) cerebral and muscle TOI were markedly decreased in SS children while the decrease of TOI was milder in SC children, 2) cerebral TOI level was associated with several biological markers in SS children only and 3) cerebral vasomotion was enhanced in SS, possibly to counterbalance the effects of chronic cerebral hypoxia.
ISSN: 1079-9796

hal-01668321
https://hal.univ-antilles.fr/hal-01668321
DOI : 10.1016/j.bcmd.2017.03.015

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
ISSN: 0007-1048

hal-01679026
https://hal.univ-antilles.fr/hal-01679026
DOI : 10.1111/bjh.14693