Synchronization by low-amplitude light-dark cycles of 24-hour pineal and plasma melatonin rhythms of hatchling European starlings (Sturnus vulgaris)

In young European starlings, as in other avian species, high-amplitude 24-hr rhythms in plasma and pineal melatonin are already present around the time of hatching. In chickens this rhythmicity results at least partly from the light sensitivity of the melatonin-producing and -secreting system. In contrast to the chicken, the starling is a hole-nesting bird, and it seemed questionable whether the low light intensities in the nest are sufficient to synchronize perinatal melatonin rhythms. We therefore exposed starling eggs to light cycles roughly simulating those measured in nest-boxes, i.e., an 11-hr phase of complete darkness and a 13-hr phase consisting of 15 min of dim light (10 lux) alternating with 30 min of darkness. For one group the photophase lasted from 0600 to 1900 hr; for the other group the photophase lasted from 1800 to 0700 hr. In approximately 10-hr-old hatchlings of both groups, plasma and pineal melatonin concentrations were high during the dark phase and low during the light phase. We conclude that perinatal low-amplitude light intensity changes of the kind experienced by hatching starlings in the field are sufficient for synchronizing the melatonin-producing and -secreting system in the pineal and possibly other organs.

Intensifying insulin regimen after basal insulin optimization in adults with type 2 diabetes: a 24-week, randomized, open-label trial comparing insulin glargine plus insulin glulisine with biphasic insulin aspart (LanScape)

AIM: To test the hypothesis that a 'basal plus' regimenadding once-daily main-meal fast-acting insulin to basal insulin once dailywould be non-inferior to biphasic insulin twice daily as assessed by glycated haemoglobin (HbA1c) concentration (predefined as ≤0.4%), but would provide superior treatment satisfaction. METHODS: This open-label trial enrolled adults to an 8- or 12-week run-in period, during which oral therapies except metformin were stopped and insulin glargine dose was titrated. Those with fasting glucose <7 mmol/l but HbA1c >7% (53 mmol/mol) were randomized to insulin glargine/glulisine once daily (n = 170) or insulin aspart/aspart protamine 30/70 twice daily (n = 165) for 24 weeks, with dose titration to glucose targets using standardized algorithms. RESULTS: For HbA1c, the basal plus regimen was non-inferior to biphasic insulin (least squares mean difference, 0.21%, upper 97.5% confidence limit 0.38%) meeting the predefined non-inferiority margin of 0.4%. Treatment satisfaction (Diabetes Treatment Satisfaction Questionnaire change version and Insulin Treatment Satisfaction Questionnaire total scores) significantly favoured basal plus. No difference was observed between the basal plus and the biphasic insulin groups in responders (HbA1c <7%, 20.6 vs 27.9%; p = 0.12), weight gain (2.06 vs 2.50 kg; p = 0.2), diabetes-specific quality of life (Audit of Diabetes-Dependent Quality of Life average weighted impact (AWI) score) and generic health status (five-dimension European Quality of Life questionnaire). Overall hypoglycaemia rates were similar between groups (15.3 vs 18.2 events/patient-year; p = 0.22); nocturnal hypoglycaemia was higher with the basal plus regimen (5.7 vs 3.6 events/patient-year; p = 0.02). CONCLUSION: In long-standing type 2 diabetes with suboptimal glycaemia despite oral therapies and basal insulin, the basal plus regimen was non-inferior to biphasic insulin for biomedical outcomes, with a similar overall hypoglycaemia rate but more nocturnal events.

24-h urinary sodium excretion is associated with obesity in a cross-sectional sample of Australian schoolchildren

Emerging evidence indicates that dietary Na may be linked to obesity; however it is unclear whether this relationship is independent of energy intake (EI). The aim of this study was to assess the association between Na intake and measures of adiposity, including BMI z score, weight category and waist:height ratio (WHtR), in a sample of Australian schoolchildren. This was a cross-sectional study of schoolchildren aged 4-12 years. Na intake was assessed via one 24-h urine collection. BMI was converted to age- and sex-specific z scores, and WHtR was used to define abdominal obesity. In children aged ≥8 years, EI was determined via one 24-h dietary recall. Of the 666 children with valid urine samples 55 % were male (average age 9·3 (sd 1·8) years). In adjusted models an additional 17 mmol/d of Na was associated with a 0·10 higher BMI z score (95 % CI 0·07, 0·13), a 23 % (OR 1·23; 95 % CI 1·16, 1·31) greater risk of being overweight/obese and a 15 % (OR 1·15; 95 % CI 1·09, 1·23) greater risk of being centrally obese. In the subsample of 8-12-year-old children (n 458), adjustment for EI did not markedly alter the associations between Na and adiposity outcomes. Using a robust measure of daily Na intake we found a positive association between Na intake and obesity risk in Australian schoolchildren, which could not be explained by total energy consumption. To determine whether this is a causal relationship, longitudinal studies, with high-quality measures of Na and EI, are required.