Energy gain and energy gap in normal-weight children: longitudinal data of the KOPS

Population-based prevention of overweight needs evidence-based goals consistent with our present knowledge about energy gap (i.e., daily imbalance between energy intake and energy expenditure resulting in overweight). Longitudinal data of normal-weight children (1,029 girls and 1,028 boys; Kiel Obesity Prevention Study, KOPS) were used to calculate energy gain (i.e., increase in fat mass (FM) and fat-free mass (FFM)) in normal-weight children staying normal weight (persistent children) or becoming overweight (incident children). Taking into account weight gain in proportion to height gain (normal development) energy gap was calculated from increases in FM and FFM exceeding normal development. Children were divided into two groups and were followed from age 6 to 10 (group A) and 10 to 14 years (group B). FM and FFM were measured. Medians of 4-year BMI- (kg/m(2))/weight changes (kg) were +1.8/+13.2 (A) and +3.0/+18.7 (B) in girls, and +1.6/+12.8 (A) and +2.6/21.7 (B) in boys. Corresponding data for FM/FFM (kg) were +3.1/+10.2 (A) and +5.1/12.7 (B) in girls, and +2.3/10.8 (A) and +3.0/18.6 (B) in boys. The 4-year-incidence of overweight (%) were 9.4 (A) and 5.4 (B) in girls, and 11.0 (A) and 3.8 (B) in boys, respectively. Mean energy gains (kcal/day) were 26.8 (A) and 46.4 (B) in girls, and 22.1 (A) and 32.5 (B) in boys. The 90th percentile of energy gap (kcal/day) in incident children were 58.1 (A) and 72.0 (B) in girls and 46.0 (A) and 53.2 (B) in boys. To prevent overweight in children energy gap should not exceed 46-72 kcal/day.     

Spontaneous neurotransmitter release and Ca2+--how spontaneous is spontaneous neurotransmitter release?

Neurotransmitter release from neurons takes place at specialized structures called synapses. Action potential-evoked exocytosis requires Ca(2+) influx through voltage-gated Ca(2+) channels. Spontaneous vesicle fusion occurs both in the absence of action potentials and without any apparent stimulus and is hence thought to be Ca(2+)-independent. However, increasing evidence shows that this form of neurotransmitter discharge can be modulated by changes in intracellular Ca(2+) concentration, suggesting that it is not truly spontaneous. This idea is supported by the fact that spontaneous release can be modulated by interfering with proteins involved in the exocytotic process. Interestingly, modulation of spontaneous discharge at the level of the release machinery is not always accompanied by corresponding modulation of action potential-evoked release, suggesting that two independent processes may underlie spontaneous and action potential-evoked exocytosis, at least at some synapses. This provides an attractive model whereby cells can modulate the two forms of neurotransmitter liberation, which often serve different physiological roles, independently of each other.     

In situ mapping of nitrifiers and anammox bacteria in microbial aggregates by means of confocal resonance Raman microscopy

In the present work the exploration of microbial communities by confocal resonance Raman microscopy (CRRM) is reported. Using the resonance Raman effect of cytochrome c (Cyt c) we were able to record the microbial distribution of nitrifiers and anammox bacteria directly in their natural environment without the need of sample preparation. For this new non-invasive investigation a reference database of bacteria assumed to be found in microbial aggregates obtained from biological wastewater treatment was created. Reference spectra of enriched cultures of the interesting bacteria were taken by means of optical tweezers. Significant spectra were achieved in less than 1 s (excitation wavelength 532 nm, laser power 9 mW) due to the resonance Raman effect. In addition, the impact of different parameters on the reference spectra, such as integration time and culture conditions, was analysed. We successfully demonstrate the grouping of bacteria down to strain level based on the heterogeneity of the resonance Raman spectra of the heme protein Cyt c.     

Pathways of bacterial contamination during egg incubation and larval rearing of turbot, Scophthalmus maximus

Overall microbial levels in the water system of a turbot farm were similar to those found in regular sea-water. At the end of an incubation period, however, the numbers of colony-forming units (CFU) in Artemiu cultures and turbot eg incubation jars were up to four orders of magnitude higher than sea-water level. Rinsing of the foot organisms (rotifers) prior to feeding them to turbot larvae, however, significantly reduced bacterial numbers, thus reducing the number of cross-contaminations. Several species of Aeromonas, Pseudomonas and Vibrio among others, were identified in the eggs and larvae, or in the water in which these were incubated. Scanning electron microscop shows that the surface of unfertilized turbot eggs is a breeding ground for bacteria; the removal of these eggs from incubation jars is therefore recommended. The epidermis of turbot larvae was virtually free ofmicroorganisms.     

Active Maintenance of T Cell Memory in Acute and Chronic Viral Infection Depends on Continuous Expression of FOXO1

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Chloroplast phosphoglycerate kinase from Euglena gracilis: endosymbiotic gene replacement going against the tide.

Two chloroplast phosphoglycerate kinase isoforms from the photosynthetic flagellate Euglena gracilis were purified to homogeneity, partially sequenced, and subsequently cDNAs encoding phosphoglycerate kinase isoenzymes from both the chloroplast and cytosol of E. gracilis were cloned and sequenced. Chloroplast phosphoglycerate kinase, a monomeric enzyme, was encoded as a polyprotein precursor of at least four mature subunits that were separated by conserved tetrapeptides. In a Neighbor-Net analysis of sequence similarity with homologues from numerous prokaryotes and eukaryotes, cytosolic phosphoglycerate kinase of E. gracilis showed the highest similarity to cytosolic and glycosomal homologues from the Kinetoplastida. The chloroplast isoenzyme of E. gracilis did not show a close relationship to sequences from other photosynthetic organisms but was most closely related to cytosolic homologues from animals and fungi.