12 research outputs found
Differences in the faecal microbiome in Schistosoma haematobium infected children vs. uninfected children
BACKGROUND: Several infectious diseases and therapeutic interventions cause gut microbe dysbiosis and associated pathology. We characterised the gut microbiome of children exposed to the helminth Schistosoma haematobium pre- and post-treatment with the drug praziquantel (PZQ), with the aim to compare the gut microbiome structure (abundance and diversity) in schistosome infected vs. uninfected children. METHODS: Stool DNA from 139 children aged six months to 13 years old; with S. haematobium infection prevalence of 27.34% was extracted at baseline. 12 weeks following antihelminthic treatment with praziqunatel, stool DNA was collected from 62 of the 139 children. The 16S rRNA genes were sequenced from the baseline and post-treatment samples and the sequence data, clustered into operational taxonomic units (OTUs). The OTU data were analysed using multivariate analyses and paired T-test. RESULTS: Pre-treatment, the most abundant phyla were Bacteroidetes, followed by Firmicutes and Proteobacteria respectively. The relative abundance of taxa among bacterial classes showed limited variation by age group or sex and the bacterial communities had similar overall compositions. Although there were no overall differences in the microbiome structure across the whole age range, the abundance of 21 OTUs varied significantly with age (FDR<0.05). Some OTUs including Veillonella, Streptococcus, Bacteroides and Helicobacter were more abundant in children ≤ 1 year old compared to older children. Furthermore, the gut microbiome differed in schistosome infected vs. uninfected children with 27 OTU occurring in infected but not uninfected children, for 5 of these all Prevotella, the difference was statistically significant (p <0.05) with FDR <0.05. PZQ treatment did not alter the microbiome structure in infected or uninfected children from that observed at baseline. CONCLUSIONS: There are significant differences in the gut microbiome structure of infected vs. uninfected children and the differences were refractory to PZQ treatment
Pets as Sentinels of Human Exposure to Neurotoxic Metals
The idea that animals may be used as sentinels of environmental hazards
pending over humans and the associated public health implications is not a new one.
Nowadays pets are being used as bioindicators for the effects of environmental contaminants
in human populations. This is of paramount importance due to the large
increase in the worldwide distribution of synthetic chemicals, particularly in the
built environment. Companion animals share the habitat with humans being simultaneously
exposed to and suffering the same disease spectrum as their masters.
Moreover, their shorter latency periods (due to briefer lifespans) enable them to act
as early warning systems, allowing timely public health interventions. The rise on
ethical constraints on the use of animals and, consequently, on the sampling they
can be subjected to has led to the preferential use of noninvasive matrices, and in
this case we are looking into hair. This chapter focuses in three non-essential metals:
mercury, lead, and cadmium, due to their ubiquitous presence in the built environment
and their ability of affecting the mammal nervous system. There is a fairly
short amount of studies reporting the concentrations of these metals in pets’ hair,
particularly for cats. These studies are characterized, and the metal concentrations
corresponding to different parameters (e.g., age, sex, diet, rearing) are described in
order to provide the reader with a general vision on the use of this noninvasive
matrix on the studies conducted since the last two decades of the twentieth
century.publishe