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Xavier Waltz - One of the best experts on this subject based on the ideXlab platform.

  • impaired blood rheology plays a role in the ChroniC disorders assoCiated with siCkle Cell Hemoglobin C disease
    Haematologica, 2014
    Co-Authors: Nathalie Lemonne, Xavier Waltz, Yann Lamarre, Marc Romana, Marie Dominique Hardydessources, Francois Lionnet
    Abstract:

    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.

  • relationships between systemiC vasCular resistanCe blood rheology and nitriC oxide in Children with siCkle Cell anemia or siCkle Cell Hemoglobin C disease
    Clinical Hemorheology and Microcirculation, 2014
    Co-Authors: Yann Lamarre, Xavier Waltz, Marc Romana, Marie Dominique Hardydessources, Marie Laure Lalannemistrih, Marie Petras, Lydia Doumdo, Anne Blanchetdeverly, Jean Martino, Benoit Tressieres
    Abstract:

    VasCular funCtion has been found to be impaired in patients with siCkle Cell disease (SCD). The present study investigated the determinants of systemiC vasCular resistanCe in two main SCD syndromes in Children: siCkle Cell anemia (SCA) and siCkle Cell-Hemoglobin C disease (SCC). NitriC oxide metabolites (NOx), hematologiCal, hemorheologiCal, and hemodynamiCal parameters were investigated in 61 Children with SCA and 49 Children with SCC. While mean arterial pressure was not different between SCA and SCC Children, systemiC vasCular resistanCe (SVR) was greater in SCC Children. Although SVR and blood visCosity (ηb) were not Correlated in SCC Children, the inCrease of ηb (+18%) in SCC Children Compared to SCA Children results in a greater mean SVR in this former group. SVR was positively Correlated with ηb, Hemoglobin (Hb) level and RBC deformability, and negatively with NOx level in SCA Children. Multivariate linear regression model showed that both NOx and Hb levels were independently assoCiated with SVR in SCA Children. In SCC Children, only NOx level was assoCiated with SVR. In ConClusion, vasCular funCtion of SCC Children seems to better Cope with higher ηb Compared to SCA Children. SinCe the oCCurrenCe of vaso-oCClusive like CompliCations are less frequent in SCC than in SCA Children, this finding suggests a pathophysiologiCal link between the vasCular funCtion alteration and these CliniCal manifestations. In addition, our results suggested that nitriC oxide metabolism plays a key role in the regulation of SVR, both in SCA and SCC.

  • Severe proliferative retinopathy is assoCiated with blood hypervisCosity in siCkle Cell Hemoglobin-C disease but not in siCkle Cell anemia.
    Clinical Hemorheology and Microcirculation, 2013
    Co-Authors: Christophe Lemaire, Nathalie Lemonne, Sadri Chahed, Florence Cabot, Ioana Botez, Benoit Tressieres, Marie-laure Lalanne-mistrih, Xavier Waltz, Yann Lamarre, Maryse Etienne-julan
    Abstract:

    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.

Maryse Etienne-julan - One of the best experts on this subject based on the ideXlab platform.

  • Severe proliferative retinopathy is assoCiated with blood hypervisCosity in siCkle Cell Hemoglobin-C disease but not in siCkle Cell anemia.
    Clinical Hemorheology and Microcirculation, 2013
    Co-Authors: Christophe Lemaire, Nathalie Lemonne, Sadri Chahed, Florence Cabot, Ioana Botez, Benoit Tressieres, Marie-laure Lalanne-mistrih, Xavier Waltz, Yann Lamarre, Maryse Etienne-julan
    Abstract:

    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.

  • Red blood Cell aggregation, aggregate strength and oxygen transport potential of blood are abnormal in both homozygous siCkle Cell anemia and siCkle-Hemoglobin C disease
    Haematologica, 2009
    Co-Authors: Julien Tripette, Tamas Alexy, Daniele Mougenel, Eric Beltan, Tawfik Chalabi, Roger Chout, Maryse Etienne-julan, Marie-dominique Hardy-dessources, Olivier Hue, H. J. Meiselman
    Abstract:

    BaCkground: ReCent evidenCe suggests that red blood Cell aggregation and the ratio of hematoCrit to blood visCosity (HVR), an index of the oxygen transport potential of blood, might Considerably modulate blood flow dynamiCs in the miCroCirCulation. It thus seems likely that these faCtors Could play a role in siCkle Cell disease. Design and Methods: We Compared red blood Cell aggregation CharaCteristiCs, blood visCosity and HVR at different shear rates between siCkle Cell anemia and siCkle Cell Hemoglobin C disease (SCC) patients, siCkle Cell trait Carriers (AS) and Control individuals (AA). Results: Blood visCosity determined at high shear rate was lower in siCkle Cell anemia (n=21) than in AA (n=52), AS (n=33) or SCC (n=21), and was markedly inCreased in both SCC and AS. Despite differenCes in blood visCosity, both siCkle Cell anemia and SCC had similar low HVR values Compared to both AA and AS. SiCkle Cell anemia (n=21) and SCC (n=19) subjeCts had a lower red blood Cell aggregation index and longer time for red blood Cell aggregates formation than AA (n=16) and AS (n=15), and a 2 to 3 fold greater shear rate required to disperse red blood Cell aggregates. ConClusions: The low HVR levels found in siCkle Cell anemia and SCC indiCates a Comparable low oxygen transport potential of blood in both genotypes. Red blood Cell aggregation properties are likely to be involved in the pathophysiology of siCkle Cell disease: the inCreased shear forCes needed to disperse red blood Cell aggregates may disturb blood flow, espeCially at the miCroCirCulatory level, sinCe red blood Cell are only able to pass through narrow Capillaries as single Cells rather than as aggregates. ©2009 Ferrata Storti Foundation.

Yann Lamarre - One of the best experts on this subject based on the ideXlab platform.

  • impaired blood rheology plays a role in the ChroniC disorders assoCiated with siCkle Cell Hemoglobin C disease
    Haematologica, 2014
    Co-Authors: Nathalie Lemonne, Xavier Waltz, Yann Lamarre, Marc Romana, Marie Dominique Hardydessources, Francois Lionnet
    Abstract:

    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.

  • relationships between systemiC vasCular resistanCe blood rheology and nitriC oxide in Children with siCkle Cell anemia or siCkle Cell Hemoglobin C disease
    Clinical Hemorheology and Microcirculation, 2014
    Co-Authors: Yann Lamarre, Xavier Waltz, Marc Romana, Marie Dominique Hardydessources, Marie Laure Lalannemistrih, Marie Petras, Lydia Doumdo, Anne Blanchetdeverly, Jean Martino, Benoit Tressieres
    Abstract:

    VasCular funCtion has been found to be impaired in patients with siCkle Cell disease (SCD). The present study investigated the determinants of systemiC vasCular resistanCe in two main SCD syndromes in Children: siCkle Cell anemia (SCA) and siCkle Cell-Hemoglobin C disease (SCC). NitriC oxide metabolites (NOx), hematologiCal, hemorheologiCal, and hemodynamiCal parameters were investigated in 61 Children with SCA and 49 Children with SCC. While mean arterial pressure was not different between SCA and SCC Children, systemiC vasCular resistanCe (SVR) was greater in SCC Children. Although SVR and blood visCosity (ηb) were not Correlated in SCC Children, the inCrease of ηb (+18%) in SCC Children Compared to SCA Children results in a greater mean SVR in this former group. SVR was positively Correlated with ηb, Hemoglobin (Hb) level and RBC deformability, and negatively with NOx level in SCA Children. Multivariate linear regression model showed that both NOx and Hb levels were independently assoCiated with SVR in SCA Children. In SCC Children, only NOx level was assoCiated with SVR. In ConClusion, vasCular funCtion of SCC Children seems to better Cope with higher ηb Compared to SCA Children. SinCe the oCCurrenCe of vaso-oCClusive like CompliCations are less frequent in SCC than in SCA Children, this finding suggests a pathophysiologiCal link between the vasCular funCtion alteration and these CliniCal manifestations. In addition, our results suggested that nitriC oxide metabolism plays a key role in the regulation of SVR, both in SCA and SCC.

  • Severe proliferative retinopathy is assoCiated with blood hypervisCosity in siCkle Cell Hemoglobin-C disease but not in siCkle Cell anemia.
    Clinical Hemorheology and Microcirculation, 2013
    Co-Authors: Christophe Lemaire, Nathalie Lemonne, Sadri Chahed, Florence Cabot, Ioana Botez, Benoit Tressieres, Marie-laure Lalanne-mistrih, Xavier Waltz, Yann Lamarre, Maryse Etienne-julan
    Abstract:

    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.

Marilyn F M Johnston - One of the best experts on this subject based on the ideXlab platform.

  • blood transfusion aCquired Hemoglobin C
    Archives of Pathology & Laboratory Medicine, 2009
    Co-Authors: Adrian A Suarez, Jacek M Polski, Brenda J Grossman, Marilyn F M Johnston
    Abstract:

    AbstraCt UnexpeCted and Confusing laboratory test results Can oCCur if a blood sample is inadvertently ColleCted following a blood transfusion. A potential for transfusion-aCquired Hemoglobinopathy exists beCause heterozygous individuals show no signifiCant abnormalities during the blood donor sCreening proCess. SuCh spurious results are infrequently reported in the mediCal literature. We report a Case of Hemoglobin C passively transferred during a red blood Cell transfusion. The proper interpretation in our Case was assisted by CalCulations Comparing expeCted Hemoglobin C ConCentration with the measured value. A review of the literature on transfusion-related preanalytiC errors is provided.

  • Blood Transfusion–ACquired Hemoglobin C
    Archives of Pathology & Laboratory Medicine, 2009
    Co-Authors: Adrian A Suarez, Jacek M Polski, Brenda J Grossman, Marilyn F M Johnston
    Abstract:

    AbstraCt UnexpeCted and Confusing laboratory test results Can oCCur if a blood sample is inadvertently ColleCted following a blood transfusion. A potential for transfusion-aCquired Hemoglobinopathy exists beCause heterozygous individuals show no signifiCant abnormalities during the blood donor sCreening proCess. SuCh spurious results are infrequently reported in the mediCal literature. We report a Case of Hemoglobin C passively transferred during a red blood Cell transfusion. The proper interpretation in our Case was assisted by CalCulations Comparing expeCted Hemoglobin C ConCentration with the measured value. A review of the literature on transfusion-related preanalytiC errors is provided.

Samyong Park - One of the best experts on this subject based on the ideXlab platform.

  • struCtures and oxygen affinities of Crystalline human Hemoglobin C β6 glu lys in the r and r2 quaternary struCtures
    Journal of Biological Chemistry, 2011
    Co-Authors: Naoya Shibayama, Kanako Sugiyama, Samyong Park
    Abstract:

    ReCent CrystallographiC studies suggested that fully liganded human Hemoglobin Can adopt multiple quaternary Conformations that inClude the two previously solved relaxed Conformations, R and R2, whereas fully unliganded deoxyHemoglobin may adopt only one T (tense) quaternary Conformation. An important unanswered question is whether R, R2, and other relaxed quaternary Conformations represent different physiologiCal states with different oxygen affinities. Here, we answer this question by showing the oxygen equilibrium Curves of single Crystals of human Hemoglobin in the R and R2 state. In this study, we have used a naturally oCCurring mutant Hemoglobin C (β6 Glu→Lys) to stabilize the R and R2 Crystals. Additionally, we have refined the x-ray Crystal struCture of CarbonmonoxyHemoglobin C, in the R and R2 state, to 1.4 and 1.8 Å resolution, respeCtively, to Compare preCisely the struCtures of both types of relaxed states. Despite the large quaternary struCtural differenCe between the R and R2 state, both Crystals exhibit similar nonCooperative oxygen equilibrium Curves with a very high affinity for oxygen, Comparable with the fourth oxygen equilibrium Constant (K4) of human Hemoglobin in solution. One small differenCe is that the R2 Crystals have an oxygen affinity that is 2–3 times higher than that of the R Crystals. These results demonstrate that the funCtional differenCe between the two typiCal relaxed quaternary Conformations is small and physiologiCally less important, indiCating that these relaxed Conformations simply refleCt a struCtural polymorphism of a high affinity relaxed state.

  • StruCtures and oxygen affinities of Crystalline human Hemoglobin C (β6 Glu->Lys) in the R and R2 quaternary struCtures.
    Journal of Biological Chemistry, 2011
    Co-Authors: Naoya Shibayama, Kanako Sugiyama, Samyong Park
    Abstract:

    ReCent CrystallographiC studies suggested that fully liganded human Hemoglobin Can adopt multiple quaternary Conformations that inClude the two previously solved relaxed Conformations, R and R2, whereas fully unliganded deoxyHemoglobin may adopt only one T (tense) quaternary Conformation. An important unanswered question is whether R, R2, and other relaxed quaternary Conformations represent different physiologiCal states with different oxygen affinities. Here, we answer this question by showing the oxygen equilibrium Curves of single Crystals of human Hemoglobin in the R and R2 state. In this study, we have used a naturally oCCurring mutant Hemoglobin C (β6 Glu→Lys) to stabilize the R and R2 Crystals. Additionally, we have refined the x-ray Crystal struCture of CarbonmonoxyHemoglobin C, in the R and R2 state, to 1.4 and 1.8 Å resolution, respeCtively, to Compare preCisely the struCtures of both types of relaxed states. Despite the large quaternary struCtural differenCe between the R and R2 state, both Crystals exhibit similar nonCooperative oxygen equilibrium Curves with a very high affinity for oxygen, Comparable with the fourth oxygen equilibrium Constant (K4) of human Hemoglobin in solution. One small differenCe is that the R2 Crystals have an oxygen affinity that is 2–3 times higher than that of the R Crystals. These results demonstrate that the funCtional differenCe between the two typiCal relaxed quaternary Conformations is small and physiologiCally less important, indiCating that these relaxed Conformations simply refleCt a struCtural polymorphism of a high affinity relaxed state.