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This paper describes a spectroscopic approach for hyperspectral imaging of plasmodium falciparum infected human red blood cells (RBCs). We have performed a broad-band hyperspectral microscope which has been used to acquire a number of images in 370 nm to 1100 nm range, from fresh human RBCs infected by plasmodium falciparum. These images have been analyzed using the fast computation of entropies and mutual information for color and multispectral images. This has allowed us to determine the matching set of wavelengths for spectroscopic and morphological studies. Extracted quantitative absorption spectra of parts of parasites are presented. This set of data has also been analysis using the Principal Component Analysis. The calculated data permit us to find out the correlation of all the RGB components of the data sets. The outcome has been interpreted as qualitative spectroscopic information on the trophozoite. These results open up the possibility to classify the biological structures contained by the parasite using hyperspectral imaging.

BackgroundIn Caucasians, regular consumption of cocoa induces a drop in arterial blood pressure via an increase in nitric oxide (NO) production. However, black individuals have a different NO biodisponibility compared to Caucasians. The aim of this study was to determine, in black Africans, the physiological variations in arterial blood pressure among cocoa consumers.MethodIn total, 49 male black African volunteers, aged between 18 and 30 years old, were randomized into two groups; those consuming 10 g of cocoa powder per day (1,680 mg of flavonoids per day) for 3 weeks (consumer group), and those not consuming cocoa (control group). Systolic (SBP) and diastolic blood pressures (DBP), and heart rate (HR) were measured in the morning on an empty stomach (fasting), on day (D) 1 (without cocoa), D8, D15, and D22. Data were collected by groups and by subgroups established according to the level of SBP, DBP, or HR on D1. The means and variations of the means (between D1 and the subsequent days) of the recorded parameters were calculated and compared between groups and between subgroups.ResultsOn D8, the variations in SBP in the consumer group were significantly different from the control group (−3.72 ± 6.01 versus 0.57 ± 6.66 mmHg; p = 0.02). Between the control and consumer subgroups according to SBP, no statistical difference in the means or variations in SBP was noted. On D8 and D22, the variations in the SBP of consumers with SBP ≥ 110 mmHg on D1 were significantly different from those of other consumers (D8: −6.55 ± 5.96 versus −1.1 ± 4.93 mmHg; p = 0.01; D22: −6.63 ± 7.77 versus 0.35 ± 5.58 mmHg; p = 0.01). In the subgroups with a DBP < 75 mmHg on D1, the mean DBP of the consumers was significantly lower than that of the controls on D8 (65 ± 5 versus 69 ± 6 mmHg; p = 0.03).ConclusionIn young black African men living in Côte d’Ivoire, regular consumption of cocoa resulted in a decrease in SBP and DBP. The decrease in SBP appeared to be greater the higher the baseline SBP was.

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