Urinary metabolomics reveals unique metabolic signatures in infants with cystic fibrosis

BACKGROUND

Biologic pathways and metabolic mechanisms underpinning early systemic disease in cystic fibrosis (CF) are poorly understood. The Baby Observational and Nutrition Study (BONUS) was a prospective multi-center study of infants with CF with a primary aim to examine the current state of nutrition in the first year of life. Its secondary aim was to prospectively explore concurrent nutritional, metabolic, respiratory, infectious, and inflammatory characteristics associated with early CF anthropometric measurements. We report here metabolomics differences within the urine of these infants as compared to infants without CF.

METHODS

Urine metabolomics was performed for 85 infants with predefined clinical phenotypes at approximately one year of age enrolled in BONUS via Ultrahigh Performance Liquid Chromatography-Tandem Mass Spectroscopy (UPLC-MS/MS). Samples were stratified by disease status (non-CF controls (n = 22); CF (n = 63, All-CF)) and CF clinical phenotype: respiratory hospitalization (CF Resp, n = 22), low length (CF LL, n = 23), and low weight (CF LW, n = 15).

RESULTS

Global urine metabolomics profiles in CF were heterogeneous, however there were distinct metabolic differences between the CF and non-CF groups. Top pathways altered in CF included tRNA charging and methionine degradation. ADCYAP1 and huntingtin were identified as predicted unique regulators of altered metabolic pathways in CF compared to non-CF. Infants with CF displayed alterations in metabolites associated with bile acid homeostasis, pentose sugars, and vitamins.

CONCLUSIONS

Predicted metabolic pathways and regulators were identified in CF infants compared to non-CF, but metabolic profiles were unable to discriminate between CF phenotypes. Targeted metabolomics provides an opportunity for further understanding of early CF disease.

TRIAL REGISTRATION

United States ClinicalTrials.Gov registry NCT01424696 (clinicaltrials.gov).

A notational analysis of elite tennis strategy

A notational analysis of singles events at all four Grand Slam tournaments between 1997 and 1999 was conducted to determine the influence of the sex of the player and court surface on elite tennis strategy. Rallies of 7.1 +/- 2.0 s in women's singles were significantly longer than those in men's singles (5.2 +/- 1.8 s; P < 0.001). Rallies of 6.3 +/- 1.8 s at the Australian Open, 7.7 +/- 1.7 s at the French Open, 4.3 +/- 1.6 s at Wimbledon and 5.8 +/- 1.9 s at the US Open were recorded. Rallies were significantly longer at the French Open than at any other tournament (P< 0.05) and significantly shorter at Wimbledon than at any other tournament (P< 0.05). In women's singles, 52.8 +/- 12.4% of points were baseline rallies, significantly more than in men's singles (28.6 +/- 19%; P < 0.001). The proportion of baseline rallies played at the French Open (51.9 +/- 14.2% of points) was significantly greater than at the Australian Open (46.6 +/- 12.5%), Wimbledon (19.7 +/- 19.4%) and the US Open (35.4 +/- 19.5%; P < 0.05). The results show that both the sex of the player and surface of the court have a significant influence on the nature of singles tennis at Grand Slam tournaments.

Measuring services: a district nursing dependency tool

The government has highlighted the importance of reducing inequalities in health and providing an equal and high quality service to all patients. The district nursing service in Wolverhampton monitors the provision of services across the town to ensure high quality care for all patients.

Innovations in quality

To strengthen their operations many hospitals have embraced total quality management (TQM) strategies used by companies throughout the world. California Hospitals examines how some of these hospitals have used TQM to improve clinical outcomes, cut costs, boost staff morale and increase patient satisfaction.

19-Nor deoxycorticosterone (19-nor DOC): mineralocorticoid receptor affinity higher than aldosterone, electrolyte activity lower

By screening urine extracts from rats with adrenal regeneration hypertension, Gomez-Sanchez et al. found a steroid, subsequently identified as 19-nor DOC, with high affinity for tritiated aldosterone (3HA) binding sites in rat kidney cytosol. We here report studies on the affinity of authentic 19-nor DOC for mineralocorticoid receptors, its binding in plasma and its activity in the rat urinary mineralocorticoid assay. When kidney slices from adrenalectomized rats were incubated in protein-free buffer with 3HA, 19-nor DOC consistently competed better (approximately 140%) for 3HA binding sites than did equivalent concentrations of non-radioactive aldosterone. Under identical conditions, save for the inclusion of 20% adrenalectomized rat plasma in the incubation medium, 19-nor DOC shows only approximately 40% the potency of aldosterone in displacing 3HA. Determination of renal binding of 3HA after injection of 3HA +/- aldosterone +/- 19-nor DOC in vivo similarly shows 19-nor DOC to be approximately one third as potent a competitor for 3HA binding sites as aldosterone. In the rat urinary bioassay, 19-nor DOC shows no antagonist activity when injected with aldosterone; in the absence of aldosterone, 19-nor DOC acts as a mineralocorticoid agonist, with an apparent potency 10-30% that of aldosterone. Conclusions of the study are therefore (i) at a molecular level, 19-nor DOC has a higher affinity than aldosterone for mineralocorticoid receptors, (ii) in vivo, its potency in terms of receptor occupancy is markedly lower than that of aldosterone, due to higher levels of plasma binding, (iii) in effector terms, 19-nor DOC is a full agonist without antagonist activity.