Rapid haemoglobin A and S quantification using Tosoh HLC-723G8 in variant mode for patients with sickle cell disease.

The management of life-threatening complications in patients with sickle cell disease (SCD) requires an accurate and reproducible quantification of haemoglobin A (HbA) and S (HbS) with a short turnaround time and 24-7 availability. We propose a novel method for quantifying HbA and HbS using the glycated haemoglobin (HbA1c) assay on a Tosoh HLC-723G8 (G8) analyser in variant mode. HbA and HbS results obtained using our method highly correlated with results obtained using a reference method (r > 0.99 for 124 samples of patients with SCD or sickle cell trait). Our method met laboratory requirements for linearity (coefficient of variation [CV] and bias <5%), between-run and within-run reproducibility (CV <10%) and carryover (<0.5%) over the range of HbS and HbA values expected in a therapeutic context. Using the G8 analyser in variant mode is viable for monitoring HbA and HbS concentrations in dire situations. This method is easy to use, quick (1.6 min per sample), and automatable and produces highly reproducible results without significant bias. Finally, it does not require modifications to the analytical pipeline recommended by the supplier, enabling a 24-7 availability without disrupting routine monitoring of HbA1c in the laboratory.

The cytokine profile of follicular fluid changes during ovarian ageing.

OBJECTIVE: Ovarian ageing is one of the commonest causes of infertility in patients consulting for assisted reproductive technology. The composition of the follicular fluid (FF), which reflects the exchanges between the oocyte and its microenvironment, has been extensively investigated to determine the metabolic pathways involved in various ovarian disorders. Considering the importance of cytokines in folliculogenesis, we focused on the cytokine profile of the FF during ovarian ageing. MATERIAL AND METHODS: Our cross-sectional study assesses the levels of 27 cytokines and growth factors in the FF of two groups of women undergoing in vitro fertilization. One group included 28 patients with ovarian ageing clinically characterized by a diminished ovarian reserve (DOR), and the other group included 29 patients with a normal ovarian reserve (NOR), serving as controls. RESULTS: With univariate analysis, the cytokine profile was found to differ significantly between the two groups. After adjustment of the p-values, platelet-derived growth factor-BB (PDGF-BB) was the only cytokine with a significantly lower concentration in the DOR group (7.34 ± 16.11 pg/mL) than in the NOR group (24.39 ± 41.38 pg/mL) (p = 0.005), independently of chronological age. CONCLUSION: Thus, PDGF-BB would seem to be implicated in the physiopathology of DOR, potentially in relation to its role in folliculogenesis or in the protection against oxidative stress.

[Multiparametric biochemical analysis revealing an increase of homocysteinemia and NT-proBNP in hypertensive patients living in Bamako (Mali)]. / Analyse biochimique multi-paramétrique révélant une augmentation de l'homocystéinémie et du NT-ProBNP chez les patients hypertendus à Bamako (Mali).

INTRODUCTION: Arterial hypertension is a major public health problem in sub-Saharan Africa due to its high frequency and to the cardiovascular risk that it entails. The purpose of this study was to assess the prevalence of clinical and biological risk factors of hypertension in Bamako (Mali). METHODS: We conducted a case-control study, stratified in function of the sex, of 72 participants including 36 patients with hypertension and 36 controls. Twenty-two plasma biochemical parameters have been measured and analyzed using univariate and multivariate tests. RESULTS: Hyperhomocysteinemia was found in 55.6% of women (p = 0.03) and 100% of men (p = 0.007) with hypertension. High NT-proBNP was also found in 16.7% of women (VIP > 1 in multivariate model) and of men with hypertension (p = 0.00006). A good multivariate predictive model (OPLS-DA) was only obtained in women with high blood pressure, with Q2cum = 0.73, attesting severe sexual dimorphism associated with arterial hypertension. This model involved eight parameters whose plasma concentration was modified (homocysteine, NT-proBNP, potassium, urea, blood glucose, sodium, chlorine and total proteins). CONCLUSION: We registered a significant association between hyperhomocysteinemia and arterial hypertension. Therefore, the assay of homocysteine associated with good management would decrease the risk of cardiovascular diseases while improving the quality of life of hypertensive patients.

Retinal metabolic events in preconditioning light stress as revealed by wide-spectrum targeted metabolomics.

INTRODUCTION: Light is the primary stimulus for vision, but may also cause damage to the retina. Pre-exposing the retina to sub-lethal amount of light (or preconditioning) improves chances for retinal cells to survive acute damaging light stress. OBJECTIVES: This study aims at exploring the changes in retinal metabolome after mild light stress and identifying mechanisms that may be involved in preconditioning. METHODS: Retinas from 12 rats exposed to mild light stress (1000 lux × for 12 h) and 12 controls were collected one and seven days after light stress (LS). One retina was used for targeted metabolomics analysis using the Biocrates p180 kit while the fellow retina was used for histological and immunohistochemistry analysis. RESULTS: Immunohistochemistry confirmed that in this experiment, a mild LS with retinal immune response and minimal photoreceptor loss occurred. Compared to controls, LS induced an increased concentration in phosphatidylcholines. The concentration in some amino acids and biogenic amines, particularly those related to the nitric oxide pathway (like asymmetric dimethylarginine (ADMA), arginine and citrulline) also increased 1 day after LS. 7 days after LS, the concentration in two sphingomyelins and phenylethylamine was found to be higher. We further found that in controls, retina metabolome was different between males and females: male retinas had an increased concentration in tyrosine, acetyl-ornithine, phosphatidylcholines and (acyl)-carnitines. CONCLUSIONS: Besides retinal sexual metabolic dimorphism, this study shows that preconditioning is mostly associated with re-organisation of lipid metabolism and changes in amino acid composition, likely reflecting the involvement of arginine-dependent NO signalling.