High blood viscosity is associated with high pulse wave velocity in African sickle cell trait carriers

Background: Sickle cell trait (SCT) is the benign condition of sickle cell disease. Often asymptomatic, the SCT carriers have hemorheological disturbances such as blood hyper-viscosity compared to healthy subjects. These disturbances could lead to structural and functional changes in large vessels. The aim of the study was to evaluate the association between blood viscosity (ηb) and pulse wave velocity (PWV) in SCT carriers.Methods: Thirteen SCT with high blood viscosity (SCT_hηb) aged 34±12 years (4 men) were compared to 13 SCT with low blood viscosity (SCT_lηb) aged 32±9 years (5 men) recruited from the National Blood Transfusion Center (CNTS) in Dakar (Senegal). Pulse wave velocity finger-toe (PWVft) was assessed using pOpmètre® (Axelife SAS-France). Cardiovascular risk (CVR) was assessed according to the Framingham Laurier score.Results: SCT_hηb had higher PWVft (m/s) than SCT_lηb respectively 8.98±1.98 and 7.11±1.18 (p = 0.004). CVR score (%) was higher in SCT_hηb than SCT_lηb, but this difference was not statistically significant (5.96±7.45 vs 2.09±2.15; p=0.31). Multivariate linear regression showed a positive correlation between PWVft and ηb and CVR score (r2=0.74, F=21.19, p˂0.001).Conclusions: Present results indicate that the SCT_hηb carriers have arteries stiffer than SCT_lηb and ηb and CVR could remain independent determinants of arterial stiffness in SCT carriers

Evaluation of the pulse wave velocity in African rheumatoid arthritis subjects

Background: Rheumatoid arthritis is a systemic disease with often fatal vascular events. In addition to traditional cardiovascular risk factors, disease-specific elements contribute to this cardiovascular mortality. The aim of this study was to assess arterial stiffness in rheumatoid arthritis and to determine the factors involved.Methods: We have recruited the black African patients followed in rheumatology and had rheumatoid arthritis diagnosis. Only patients between 18 and 60 years and meeting the American College of Rheumatology criteria were included. All controls were healthy. We evaluated the propagation velocity of the pulse wave finger-toe (PWVft) measured by the pOpmètre®.Results: Present study shows that the PWVft was significantly elevated in over half of patients (55.10%). Besides, the mean patients PWVft was significantly higher than that of the control (respectively 9.40±0.51 and 7.22±0.33 p=0.001). In the patients, no factor was significantly involved in the arterial stiffness, but cons in the control group, the PWVft was significantly correlated with age (p=0.023 and r=0.55).Conclusions: Rheumatoid arthritis patients had higher PWVft compared to controls. Due to the importance of its cardiovascular morbidity and mortality, arthritis requires a regular monitoring element as arterial stiffness, which is currently a major vascular parameter monitoring

Effects of lenten fasting on body composition and biochemical parameters

Background: The catholic lenten fasting is the period of 40 days of fasting that precedes Easter. It is one of religious fasting less documented in the scientific literature. Thus the aim of our study was to evaluate the evolution of anthropometric and body composition and biochemical profile during Catholic lenten fasting.Methods: We conducted a prospective study, which took place during the period between one week before at the end of lenten fasting. Eleven fasters (4 women and 7 men), aged between 18 and 59 years were included in present study. Anthropometric, body composition parameters and biochemical profile were evaluated one week before, at 15th day and at the end of Lenten fasting.Results: Weight, body mass index (BMI) and visceral fat decreased significantly at the end of Lenten fasting. Lipid profile changed significantly during this fasting period. Total cholesterol (TC), low density lipoprotein – cholesterol (LDL-C) and triglycerides decreased significantly with fasting. High density lipoprotein – cholesterol (HDL-C) was remained unchanged during this fasting period while TC/HDL ratio was significantly decreased at the end of Lent.Conclusions: Present study showed that the fasting of Lent seems to have beneficial effects on reducing cardiovascular risk factors. Further studies are required to better understand the physiological mechanisms involved for a therapeutic use

In-situ fluorescence spectroscopy indicates total bacterial abundance and dissolved organic carbon

We explore in-situ fluorescence spectroscopy as an instantaneous indicator of total bacterial abundance and faecal contamination in drinking water. Eighty-four samples were collected outside of the recharge season from groundwater-derived water sources in Dakar, Senegal. Samples were analysed for tryptophan-like (TLF) and humic-like (HLF) fluorescence in-situ, total bacterial cells by flow cytometry, and potential indicators of faecal contamination such as thermotolerant coliforms (TTCs), nitrate, and in a subset of 22 samples, dissolved organic carbon (DOC). Significant single-predictor linear regression models demonstrated that total bacterial cells were the most effective predictor of TLF, followed by on-site sanitation density; TTCs were not a significant predictor. An optimum multiple-predictor model of TLF incorporated total bacterial cells, nitrate, nitrite, on-site sanitation density, and sulphate (r2 0.68). HLF was similarly related to the same parameters as TLF, with total bacterial cells being the best correlated (ρs 0.64). In the subset of 22 sources, DOC clustered with TLF, HLF, and total bacterial cells, and a linear regression model demonstrated HLF was the best predictor of DOC (r2 0.84). The intergranular nature of the aquifer, timing of the study, and/or non-uniqueness of the signal to TTCs can explain the significant associations between TLF/HLF and indicators of faecal contamination such as on-site sanitation density and nutrients but not TTCs. The bacterial population that relates to TLF/HLF is likely to be a subsurface community that develops in-situ based on the availability of organic matter originating from faecal sources. In-situ fluorescence spectroscopy instantly indicates a drinking water source is impacted by faecal contamination but it remains unclear how that relates specifically to microbial risk in this setting

Chronological Sedentary Growth is Associated with Arterial Hypertension but not with High Glycaemia in Sub-Saharan African Rural Area

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Blood viscosity is lower in trained than in sedentary sickle cell trait carriers

International audienceThe aim of this study was to compare blood and plasma viscosities, as well as the hematocrit/blood viscosity ratio (HVR), between trained and sedentary SCT carriers. Thirty African male SCT carriers from the city of Dakar (Senegal) participated in the study: one group composed of 15 trained SCT carriers (TSCTc) and one group composed of 15 sedentary individuals (SSCTc). Blood was sampled in resting condition and blood and plasma viscosities were measured using a cone-plate viscometer. After the determination of hematocrit by microcentrifugation, HVR was determined for each subject. Blood and plasma viscosities, as well as hematocrit, were significantly reduced in TSCTc compared to SSCTc. As a consequence, HRV was greater in TSCTc. These findings provide evidence that SCT carriers should be encouraged to practice regular physical activity to limit the cardiovascular strain usually caused by their blood hyperviscosity

High blood viscosity is associated with high pulse wave velocity in African sickle cell trait carriers

Background: Sickle cell trait (SCT) is the benign condition of sickle cell disease. Often asymptomatic, the SCT carriers have hemorheological disturbances such as blood hyper-viscosity compared to healthy subjects. These disturbances could lead to structural and functional changes in large vessels. The aim of the study was to evaluate the association between blood viscosity (ηb) and pulse wave velocity (PWV) in SCT carriers.Methods: Thirteen SCT with high blood viscosity (SCT_hηb) aged 34±12 years (4 men) were compared to 13 SCT with low blood viscosity (SCT_lηb) aged 32±9 years (5 men) recruited from the National Blood Transfusion Center (CNTS) in Dakar (Senegal). Pulse wave velocity finger-toe (PWVft) was assessed using pOpmètre® (Axelife SAS-France). Cardiovascular risk (CVR) was assessed according to the Framingham Laurier score.Results: SCT_hηb had higher PWVft (m/s) than SCT_lηb respectively 8.98±1.98 and 7.11±1.18 (p = 0.004). CVR score (%) was higher in SCT_hηb than SCT_lηb, but this difference was not statistically significant (5.96±7.45 vs 2.09±2.15; p=0.31). Multivariate linear regression showed a positive correlation between PWVft and ηb and CVR score (r2=0.74, F=21.19, p˂0.001).Conclusions: Present results indicate that the SCT_hηb carriers have arteries stiffer than SCT_lηb and ηb and CVR could remain independent determinants of arterial stiffness in SCT carriers

Mechanisms and consequences of alterations in vascular function in combined type 2 diabetes and sickle cell trait

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Mechanisms and consequences of alterations in vascular function in combined type 2 diabetes and sickle cell trait

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Comparison between standing and adjusted heights in Senegalese women

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