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Resistance to insecticides in the mosquito Anopheles gambiae s.l can jeopardize malaria vector control strategies. Previous studies have shown that the agricultural chemicals, used particularly for cotton protection, selected the insecticide resistant malaria vectors. Our study aimed at assessing the impact of three cotton pest management strategies in different ecological settings (conventional, organic and transgenic cotton growing areas) on the i) susceptibility to insecticides belonging to pyrethroids, DDT, carbamate and organophosphate tested on the main malaria vectors and ii) frequencies of kdr L1014F, during rainy season of 2008, 2009, 2013 and 2014 in Burkina Faso. From 2008 to 2014, most of populations of An. gambiae s.l from the three cotton growing areas exhibited a reduction in susceptibility to almost all insecticide classes. The frequency of kdr L1014F mutations varied depending on both localities and species within the An. gambiae complex, but no relationship was found between the cotton pest control strategies and the frequency of kdr L1014F. These results confirm the worrying status of insecticide multi-resistance within the vector mosquito species from Burkina Faso. [ABSTRACT FROM AUTHOR]

Inflammation is the supreme biological response to illness. In the Hauts-Bassins region, in traditional medicine, all parts of Cassia sieberiana and Piliostigma thonningii are used to treat hepatitis and inflammation. The aim of this study was to evaluate the in vitro antioxidant and anti-inflammatory activities of their aqueous extracts. High performance liquid chromatography with photodiode array (HPLC-DAD) and ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-MS/MS) analyses highlighted the presence of polyphenols and flavonoids. Antioxidant and anti-inflammatory activities were measured by various methods such as DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), TAC (total antioxidant capacity), anti-protease, anti-lipoxygenase, and membrane stabilization. The best antioxidant activity was observed in the bark (DPPH: IC50 = 13.45 ± 0.10 µg/mL) and roots (TAC = 29.68 ± 1.48 mg AAE/g DW) of Piliostigma thonningii and in the roots (ABTS: IC50 = 1.83 ± 0.34 µg/mL) of Cassia sieberiana. The best anti-inflammatory activity was observed in the bark (anti-lipoxygenase: IC50 = 13.04 ± 1.99 µg/mL) and leaves (anti-proteases: IC50 = 75.74 ± 1.07 µg/mL, membrane stabilization: IC50 = 48.32 ± 6.39 µg/mL) of Cassia sieberiana. Total polyphenols (ABTS: r = −0.679, TAC: r = 0.960) and condensed tannins (ABTS: r = −0.702, TAC: r = 0.701) were strongly correlated with antioxidant activity. Total flavonoids (anti-proteases: r = −0.729), condensed tannins (anti-proteases: r = 0.698), and vitamin C (anti-proteases: r = −0.953) were strongly correlated with anti-inflammatory activity. Total polyphenols, flavonoids, condensed tannins, and vitamin C could contribute to the antioxidant and anti-inflammatory activities of the two studied plants. These results could validate the traditional use of these plants to treat various inflammatory diseases. [ABSTRACT FROM AUTHOR]

Introduction: extended-spectrum ß-lactamases (ESBL) determinants have been detected in clinical isolates and commensal bacteria from humans and animals. We investigated, the ESBL-producing Enterobacteriaceae in stool from intensive and extensive breeding animals (cattle, pigs, and poultry) in Burkina Faso. Methods: we identified our bacterial strains by MALDI-TOF. Antimicrobial susceptibility was tested with Kirby Bauer method and ESBL genes identified by conventional Polymerase Chain Reaction (PCR). Results: from March to June 2017 in the Bobo-Dioulasso area, we investigated stool samples collected from healthy animals (cattle = 251; pigs = 250 and poultry = 397) in one (1) slaughterhouse, five (5) livestock farms, and one (1) poultry market. The frequency of ESBL gene carriage was 41.03% among cattle, 69.60% among pigs, 0.8% among intensive farming, and 19.1% among extensive poultry farming. Only all the poultry were fed with antibiotics. The bacterial strains carrying the ESBL were E. coli (278/315) and K. pneumonia (36/315). The ESBL genes carried were CTX-M 15, TEM, and Oxa-1-like. These three ß-lactamase genes were associated in some bacterial strains. The E. coli strains belonged most commonly to the phylogroup A. Conclusion: this high level of resistance of Enterobacteriaceae to antibiotics in livestock in Burkina Faso by the production of ESBL, could suggest environmental contamination of the livestock with ESBL-producing bacteria. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus is a major cause of serious illness and death in children, indicating the need to monitor prevalent strains, particularly in the vulnerable pediatric population. Nasal carriage of S. aureus is important as carriers have an increased risk of serious illness due to systemic invasion by this pathogen and can transmit the infection. Recent studies have demonstrated the effectiveness of azithromycin in reducing the prevalence of nasopharyngeal carrying of pneumococci, which are often implicated in respiratory infections in children. However, very few studies of the impact of azithromycin on staphylococci have been undertaken. During a clinical trial under taken in 2016, nasal swabs were collected from 778 children aged 3 to 59 months including 385 children who were swabbed before administration of azithromycin or placebo and 393 after administration of azithromycin or placebo. Azithromycin was given in a dose of 100 mg for three days, together with the antimalarials sulfadoxine-pyrimethamine and amodiaquine, on four occasions at monthly intervals during the malaria transmission season. These samples were cultured for S. aureus as well as for the pneumococcus. The S. aureus isolates were tested for their susceptibility to azithromycin (15 g), penicillin (10 IU), and cefoxitine (30 g) (Oxoid Ltd). S. aureus was isolated from 13.77% (53/385) swabs before administration of azithromycin and from 20.10% (79/393) six months after administration (PR = 1.46 [1.06; 2.01], p = 0.020). Azithromycin resistance found in isolates of S. aureus did not differ significantly before and after intervention (26.42% [14/53] vs 16.46% [13/79], (PR = 0.62 [0.32; 1.23], p = 0.172). Penicillin resistance was very pronounced, 88.68% and 96.20% in pre-intervention and in post-intervention isolates respectively, but very little Methicillin Resistance (MRSA) was detected (2 cases before and 2 cases after intervention). Monitoring antibiotic resistance in S. aureus and other bacteria is especially important in Burkina Faso due to unregulated consumption of antibiotics putting children and others at risk. [ABSTRACT FROM AUTHOR]

The experiments reported in this research paper aimed to determine the technological properties of indigenous Lactococcus lactis strains isolated from Lait caillé, a spontaneous fermented milk, from the perspective of starter culture development. Fermentations were conducted to determine the acidification patterns. The ropy character, growth in 0.04 g/ml NaCl and citrate metabolism were additionally tested. Furthermore, the rheological properties of samples from selected strains and the impact of cold storage were evaluated. Based on the rate of acidification, the indigenous strains were divided into 2 groups depending on their fermentation time, i.e. 10–13 h (fast acidifier), and up to 72 h (slow acidifier), respectively. The physiological tests suggested that most of these strains produced exopolysaccharides but none could ferment citrate. The flow properties of the samples inoculated by the fast acidifier strains showed a time-dependent shear thinning behaviour, while their viscoelastic properties corresponded structurally to those of weak gels. Cold storage decreased the viscosity and CFU counts for most of the indigenous strains tested. This study is a step towards the definition of starter cultures for African spontaneous fermented milks such as Lait caillé. [ABSTRACT FROM AUTHOR]