Gut microbial activity as influenced by fiber digestion: dynamic metabolomics in an in vitro colon simulator

Understanding the interaction between the gut microbial activity and the host is essential, and in vitro models are being used to test and develop hypotheses regarding the impact of food components/drugs on the human gut ecosystem. However, while in vitro models provide excellent possibilities for dynamic investigations, studies have commonly been restricted to analyses of few, targeted metabolites. In the present study, we employed NMR-based metabolomics combined with multilevel data analysis as a tool to characterize the impact of polydextrose (PDX) fiber on the in vitro derived fecal metabolome. This approach enabled us to identify and quantify the fiber-induced response on several fecal metabolites; we observed higher levels of butyrate, acetate, propionate, succinate, N-acetyl compound and a lower level of amino acids (leucine, valine, isoleucine, phenylalanine, and lysine), valerate, formate, isovalerate and trimethylamine among the PDX-treated sample compared to the control samples. In addition, by the application of multilevel data analysis we were able to examine the specific inter-individual variations, and caprylic acid was identified to be the main marker of distinct microbial compositions among the subjects. Our work is expected to provide a useful approach to understand the metabolic impact of potential prebiotic compounds and get deeper insight into the molecular regulation of gut-microbe activities in the complex gut system

Tylosis with oesophageal cancer: Diagnosis, management and molecular mechanisms

Research on iRHOM2 in the Kelsell group is funded by an MRC project grant, a MRC Clinical Fellowship (to TM) and a Cancer Research UK program grant

The multi-peak adaptive landscape of crocodylomorph body size evolution

Background: Little is known about the long-term patterns of body size evolution in Crocodylomorpha, the > 200-million-year-old group that includes living crocodylians and their extinct relatives. Extant crocodylians are mostly large-bodied (3–7 m) predators. However, extinct crocodylomorphs exhibit a wider range of phenotypes, and many of the earliest taxa were much smaller ( Results: Crocodylomorphs reached an early peak in body size disparity during the Late Jurassic, and underwent an essentially continual decline since then. A multi-peak Ornstein-Uhlenbeck model outperforms all other evolutionary models fitted to our data (including both uniform and non-uniform), indicating that the macroevolutionary dynamics of crocodylomorph body size are better described within the concept of an adaptive landscape, with most body size variation emerging after shifts to new macroevolutionary regimes (analogous to adaptive zones). We did not find support for a consistent evolutionary trend towards larger sizes among lineages (i.e., Cope’s rule), or strong correlations of body size with climate. Instead, the intermediate to large body sizes of some crocodylomorphs are better explained by group-specific adaptations. In particular, the evolution of a more aquatic lifestyle (especially marine) correlates with increases in average body size, though not without exceptions. Conclusions: Shifts between macroevolutionary regimes provide a better explanation of crocodylomorph body size evolution on large phylogenetic and temporal scales, suggesting a central role for lineage-specific adaptations rather than climatic forcing. Shifts leading to larger body sizes occurred in most aquatic and semi-aquatic groups. This, combined with extinctions of groups occupying smaller body size regimes (particularly during the Late Cretaceous and Cenozoic), gave rise to the upward-shifted body size distribution of extant crocodylomorphs compared to their smaller-bodied terrestrial ancestors.</p

New loci associated with birth weight identify genetic links between intrauterine growth and adult height and metabolism.

Birth weight within the normal range is associated with a variety of adult-onset diseases, but the mechanisms behind these associations are poorly understood. Previous genome-wide association studies of birth weight identified a variant in the ADCY5 gene associated both with birth weight and type 2 diabetes and a second variant, near CCNL1, with no obvious link to adult traits. In an expanded genome-wide association meta-analysis and follow-up study of birth weight (of up to 69,308 individuals of European descent from 43 studies), we have now extended the number of loci associated at genome-wide significance to 7, accounting for a similar proportion of variance as maternal smoking. Five of the loci are known to be associated with other phenotypes: ADCY5 and CDKAL1 with type 2 diabetes, ADRB1 with adult blood pressure and HMGA2 and LCORL with adult height. Our findings highlight genetic links between fetal growth and postnatal growth and metabolism

Climate Variability and Rural Livelihood Security : Impacts and Implications

In a typical Nigerian village, the majority of the population comprises old people who are mostly economically unproductive due to reduced or loss of physical strength brought about by ageing and ill health. Many of these rural old people still work, and do so outside the formal sector, and are particularly susceptible to the effects of climate variability and change. Few studies have reported on climate change and the rural aged and there is a research gap as regards rural elderly peoples’ perception of climate variability impact on them. Since little is known about their perception of climate variability impacts and implications on the rural aged especially in relation to their livelihood activities in Sub-Saharan Africa, this chapter therefore examined the impact of climate variability on the livelihood security of the rural aged in different ecological zones of Nigeria. Both qualitative and quantitative methods were used for data collection. Qualitative data were obtained through interviews with four aged and four aged women selected purposively in each rural community and analyzed using Content Analysis Method. Quantitative data were obtained through structured questionnaire administered to an aged male and an aged female population available in selected houses (the aged are people 60 years and over in age) in selected rural communities in selected ecological zones of Nigeria. Where there was no combination of the two (aged men and aged women), either of the two was also sufficient. It was discovered that the ageds’ experiences of climate variability impact relate to the prevailing climate variability characteristic of each ecological zones. The impact on their livelihood in these zones is seen in terms of livestock death, lack of pastures for herds, scarcity of water, pest invasion, delayed planting crop failure, need for irrigation, water logging, drowning of small animals, human and animal illness. This means that planning decisions related to climate change issues should take cognizance of the views of the aged populations especially of those residing in rural areas as they are the most affected by the impact