Metabonomics and Intensive Care

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency medicine 2016. Other selected articles can be found online at http://www.biomedcentral.com/collections/annualupdate2016. Further information about the Annual Update in Intensive Care and Emergency Medicine is available from http://www.springer.com/series/8901

Bryophyte colonisation and persistense in experimental microcosms-The role of nutrients, defoliation and vascular vegetation.

A three-year multi-factorial microcosms experiment simulating dry grassland was used to test five hypotheses concerning establishment and persistence of bryophytes in grassland vegetation. The experimental treatments included fertilisation, defoliation and species composition of vascular vegetation. ANOVA-modelling showed a significant response of bryophyte species richness to fertilisation (negative) and defoliation (positive). Species composition of vascular vegetation had no effect on bryophyte richness, but a significant negative relationship was found between vascular plant biomass and species richness of bryophytes. Vascular plant dry weight above 400 g m-2 appeared fatal to bryophytes. At high nutrient levels, bryophytes extinction seemed to be avoided by defoliation, but defoliation did not fully compensate for the negative effect of fertilisation on bryophyte richness. At the single species level, our experiment provided new autecological insight in the responses of Brachytecium rutabulum and Funaria hygrometrica. The relationship between bryophyte richness and bryophyte cover was shown to follow the theoretical species-area relationship, suggesting that bryophyte cover may be used as indicator of habitat quality for subordinate species such as bryophytes and lichens in grassland monitoring. The implications of the results for grassland conservation are discussed

Sarcopenia and myosteatosis are accompanied by distinct biological profiles in patients with pancreatic and periampullary adenocarcinomas

<div><p>Introduction</p><p>Pancreatic and periampullary adenocarcinomas are associated with abnormal body composition visible on CT scans, including low muscle mass (sarcopenia) and low muscle radiodensity due to fat infiltration in muscle (myosteatosis). The biological and clinical correlates to these features are poorly understood.</p><p>Methods</p><p>Clinical characteristics and outcomes were studied in 123 patients who underwent pancreaticoduodenectomy for pancreatic or non-pancreatic periampullary adenocarcinoma and who had available preoperative CT scans. In a subgroup of patients with pancreatic cancer (n = 29), <i>rectus abdominus</i> muscle mRNA expression was determined by cDNA microarray and in another subgroup (n = 29) ¹H-NMR spectroscopy and gas chromatography-mass spectrometry were used to characterize the serum metabolome.</p><p>Results</p><p>Muscle mass and radiodensity were not significantly correlated. Distinct groups were identified: sarcopenia (40.7%), myosteatosis (25.2%), both (11.4%). Fat distribution differed in these groups; sarcopenia associated with lower subcutaneous adipose tissue (P<0.0001) and myosteatosis associated with greater visceral adipose tissue (P<0.0001). Sarcopenia, myosteatosis and their combined presence associated with shorter survival, Log Rank P = 0.005, P = 0.06, and P = 0.002, respectively. In muscle, transcriptomic analysis suggested increased inflammation and decreased growth in sarcopenia and disrupted oxidative phosphorylation and lipid accumulation in myosteatosis. In the circulating metabolome, metabolites consistent with muscle catabolism associated with sarcopenia. Metabolites consistent with disordered carbohydrate metabolism were identified in both sarcopenia and myosteatosis.</p><p>Discussion</p><p>Muscle phenotypes differ clinically and biologically. Because these muscle phenotypes are linked to poor survival, it will be imperative to delineate their pathophysiologic mechanisms, including whether they are driven by variable tumor biology or host response.</p></div

Biological functions associated with differentially abundant genes for muscle radiodensity and sarcopenia.

<p>Biological functions associated with differentially abundant genes for muscle radiodensity and sarcopenia.</p

Kaplan-Meier plots.

<p>(A) Disease-free survival (DFS) as a function of sarcopenia. (B) Overall survival (OS) as a function of sarcopenia. (C) DFS as a function of myosteatosis. (D) OS as a function of myosteatosis. (E) DFS in individuals with both sarcopenia and myosteatosis. (F) OS in individuals with both sarcopenia and myosteatosis.</p

Metabolomic models that distinguish body composition phenotypes in pancreatic cancer patients.

<p>(A) OPLS-DA scores plots and metabolite lists for NMR and GC-MS metabolites: sarcopenia vs. no sarcopenia or myosteatosis. (B) OPLS-DA scores plots and metabolite lists for NMR and GC-MS metabolites: myosteatosis vs. no sarcopenia or myosteatosis. For the metabolite lists: metabolites in <b>bold</b> are shared in 1H-NMR spectroscopy and GC-MS datasets; metabolites in red have a VIP>1.</p