The impact of food additives, artificial sweeteners and domestic hygiene products on the human gut microbiome and its fibre fermentation capacity

Purpose This study investigated the effect of food additives, artificial sweeteners and domestic hygiene products on the gut microbiome and fibre fermentation capacity. Methods Faecal samples from 13 healthy volunteers were fermented in batch cultures with food additives (maltodextrin, carboxymethyl cellulose, polysorbate-80, carrageenan-kappa, cinnamaldehyde, sodium benzoate, sodium sulphite, titanium dioxide), sweeteners (aspartame-based sweetener, sucralose, stevia) and domestic hygiene products (toothpaste and dishwashing detergent). Short-chain fatty acid production was measured with gas chromatography. Microbiome composition was characterised with 16S rRNA sequencing and quantitative polymerase chain reaction (qPCR). Results Acetic acid increased in the presence of maltodextrin and the aspartame-based sweetener and decreased with dishwashing detergent or sodium sulphite. Propionic acid increased with maltodextrin, aspartame-based sweetener, sodium sulphite and polysorbate-80 and butyrate decreased dramatically with cinnamaldehyde and dishwashing detergent. Branched-chain fatty acids decreased with maltodextrin, aspartame-based sweetener, cinnamaldehyde, sodium benzoate and dishwashing detergent. Microbiome Shannon α-diversity increased with stevia and decreased with dishwashing detergent and cinnamaldehyde. Sucralose, cinnamaldehyde, titanium dioxide, polysorbate-80 and dishwashing detergent shifted microbiome community structure; the effects were most profound with dishwashing detergent (R2 = 43.9%, p = 0.008) followed by cinnamaldehyde (R2 = 12.8%, p = 0.016). Addition of dishwashing detergent and cinnamaldehyde increased the abundance of operational taxonomic unit (OTUs) belonging to Escherichia/Shigella and Klebsiella and decreased members of Firmicutes, including OTUs of Faecalibacterium and Subdoligranulum. Addition of sucralose and carrageenan-kappa also increased the abundance of Escherichia/Shigella and sucralose, sodium sulphite and polysorbate-80 did likewise to Bilophila. Polysorbate-80 decreased the abundance of OTUs of Faecalibacterium and Subdoligranulum. Similar effects were observed with the concentration of major bacterial groups using qPCR. In addition, maltodextrin, aspartame-based sweetener and sodium benzoate promoted the growth of Bifidobacterium whereas sodium sulphite, carrageenan-kappa, polysorbate-80 and dishwashing detergent had an inhibitory effect. Conclusions This study improves understanding of how additives might affect the gut microbiota composition and its fibre metabolic activity with many possible implications for human health

Learner Treatment Kit (school-based malaria diagnosis and treatment in southern Malawi): Study data and support materials

A set of data collection tools, STATA .do processing scripts, and resultant datasets produced as part of the Learner Treatment Kit (LTK) Project, a study funded to evaluate the impact of a school-based programme of malaria diagnosis and treatment (malaria case management) as part of a wider school first-aid kit exploring school attendance, health and education outcomes. The study conducted a cluster randomized controlled trial in 58 primary schools in TA Chikowi, Zomba district of southern Malawi. The intervention, implemented between 2013-2015 in 29 randomly selected schools from the total of 58 schools, comprised providing free-of-charge malaria rapid diagnostic tests (RDTs) and artemisinin-based combination therapy (ACT) to primary schools to be used by trained teachers to diagnose and treat uncomplicated malaria, as part of basic first aid kits known as "Learner Treatment Kits" (LTKs). The primary outcome was school attendance, assessed through teacher-recorded school attendance registers and periodic spot checks. Secondary outcomes included prevalence of Plasmodium spp. infection, anaemia, educational performance, self-reported child wellbeing, and health seeking behaviour. The trial is registered with ClinicalTrials.gov, NCT02213211

Learner Treatment Kit (school-based malaria diagnosis and treatment in southern Malawi): Study data and support materials

A set of data collection tools, STATA .do processing scripts, and resultant datasets produced as part of the Learner Treatment Kit (LTK) Project, a study funded to evaluate the impact of a school-based programme of malaria diagnosis and treatment (malaria case management) as part of a wider school first-aid kit exploring school attendance, health and education outcomes. The study conducted a cluster randomized controlled trial in 58 primary schools in TA Chikowi, Zomba district of southern Malawi. The intervention, implemented between 2013-2015 in 29 randomly selected schools from the total of 58 schools, comprised providing free-of-charge malaria rapid diagnostic tests (RDTs) and artemisinin-based combination therapy (ACT) to primary schools to be used by trained teachers to diagnose and treat uncomplicated malaria, as part of basic first aid kits known as "Learner Treatment Kits" (LTKs). The primary outcome was school attendance, assessed through teacher-recorded school attendance registers and periodic spot checks. Secondary outcomes included prevalence of Plasmodium spp. infection, anaemia, educational performance, self-reported child wellbeing, and health seeking behaviour. The trial is registered with ClinicalTrials.gov, NCT02213211

Ontogeny of central serotonergic neurons in the directly developing frog, Eleutherodactylus coqui

Embryonic development of the central serotonergic neurons in the directly developing frog, Eleutherodactylus coqui , was determined by using immunocytochemistry. The majority of anuran amphibians (frogs) possess a larval stage (tadpole) that undergoes metamorphosis, a dramatic post-embryonic event, whereby the tadpole transforms into the adult phenotype. Directly developing frogs have evolved a derived life-history mode where the tadpole stage has been deleted and embryos develop directly into the adult bauplan. Embryonic development in E. coqui is classified into 15 stages (TS 1–15; 1 = oviposition / 15 = hatching). Serotonergic immunoreactivity was initially detected at TS 6 in the raphe nuclei in the developing rhombencephalon. At TS 7, immunopositive perikarya were observed in the paraventricular organ in the hypothalamus and reticular nuclei in the hindbrain. Development of the serotonergic system was steady and gradual during mid-embryogenesis. However, starting at TS 13 there was a substantial increase in the number of serotonergic neurons in the paraventricular, raphe, and reticular nuclei, a large increase in the number of varicose fibers, and a differentiation of the reticular nuclei in the hindbrain. Consequentially, E. coqui displayed a well-developed central serotonergic system prior to hatching (TS 15). In comparison, the serotonergic system in metamorphic frogs typically starts to develop earlier but the surge of development that transpires in this system occurs post-embryonically, during metamorphosis, and not in the latter stages of embryogenesis, as it does in E. coqui . Overall, the serotonergic development in E. coqui is similar to the other vertebrates.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47526/1/429_2005_Article_22.pd