Changes in the acetylcholinesterase and choline acetyltransferase activities in the early development of the chick embryo

Summary Acetylcholinesterase (AChE, EC 3.1.1.7) and choline acetyltransferase (CAT, EC 2.3.1.6) activities where studied in the early development of the chick embryo. A sharp increase in AChE activity occurred in the gastrulating embryo. The highest AChE activity was associated with hypoblast cells. By sucrose density gradient centrifugation three molecular forms of AChE with sedimentation coefficients 4.7 S, 6.8 S and 10.9 S were determined. During the gastrulation there was no remarkable change in the activity of CAT. A two-fold decrease in the CAT activity occurred at the end of gastrulation.     

Size‐related life‐history traits in geometrid moths: a comparison of a temperate and a tropical community

1. Comparative studies on insect life histories are facilitated by the increasing availability of reliable phylogenies but are hampered by the scarcity of comparable data. Fortunately, morphological proxies of some life‐history traits can be measured on preserved specimens. 2. This study compared values of size‐related life‐history traits among a tropical (Ugandan) and a temperate (Estonian) assemblage of geometrid moths. 3. A comparative analysis based on an originally derived phylogeny revealed that tropical moths were, on average, larger than temperate ones. Tropical moths also had somewhat lower relative abdomen masses than temperate ones. This indicates that the tropical rather than the temperate moths tend to use an income (rather than capital) breeding strategy. Nevertheless, no difference was found in a related index of pro‐ovigeny. When body size was accounted for, tropical moths were found to lay smaller eggs than temperate ones. 4. The differences between the two compared areas are consistent with selection on higher mobility of the moths imposed by the more diverse tropical vegetation. Relatively larger eggs of temperate moths may constitute an adaptation to overcome the presumably stronger quantitative defences of their host plants. 5. Overall, however, we conclude that the differences in ecologically relevant size‐related traits are relatively low among moth assemblages of a tropical and a temperate forest region, indicating that these environments may not impose radically different selective pressures on insect life histories.     

Utilization of 15N-labelled yeast hydrolysate in Lactococcus lactis IL1403 culture indicates co-consumption of peptide-bound and free amino acids with simultaneous efflux of free amino acids

Lactococcus lactis subsp. lactis IL1403 was grown in medium containing unlabelled free amino acids and ¹⁵N-labelled yeast hydrolysate to gain insight into the role of peptides as a source of amino acids under conditions where free amino acids are abundant. A mathematical model was composed to estimate the fluxes of free and peptide-derived amino acids into and out of the intracellular amino acid pool. We observed co-consumption of peptides and free amino acids and a considerable efflux of most free amino acids during growth. We did not observe significant differences between the peptide consumption patterns of essential and non-essential amino acids, which suggests that the incorporation of a particular amino acid is more dependent on its availability in a readily assimilated form than the organism’s auxotrophy for it. For most amino acids the contribution of peptide-bound forms to the formation of biomass was initially between 30 and 60 % with the remainder originating from free amino acids. During the later stages of fermentation we observed a decrease in the utilization of peptide-bound amino acids, thus indicating that the more readily assimilated peptides are gradually exhausted from the medium during growth.     

Celebrating Multi-Religious Co-Existence in Central Kurdistan: the Bio-Culturally Diverse Traditional Gathering of Wild Vegetables among Yazidis,Assyrians, and Muslim Kurds

An ethnobotanical field study focusing on traditional wild vegetables was conducted in 22 villages of Central Kurdistan among three ethno-religious groups: Yazidis, Christian Assyrians, and (Sunni) Muslim Kurds. Through 91 interviews with elderly informants, we recorded the folk uses of 54 identified botanical taxa. We also observed important differences among these three groups in the use of wild vegetables that reflect the historical prevalence of pastoralism versus horticulture among Kurds and Assyrians, respectively. The preservation of the peaceful co-existence of different cultural and religious groups in the study area is crucial for the maintenance of the rich wild plant food local heritage.     

Objectively Measured Physical Activity and Sedentary Time during Childhood,Adolescence and Young Adulthood: A Cohort Study

Background

To know how moderate-to-vigorous physical activity (MVPA) and sedentary time change across lifespan periods is needed for designing successful lifestyle interventions. We aimed to study changes in objectively measured (accelerometry) MVPA and sedentary time from childhood to adolescence and from adolescence to young adulthood.

Methods

Estonian and Swedish participants from the European Youth Heart Study aged 9 and 15 years at baseline (N = 2312) were asked to participate in a second examination 6 (Sweden) to 9/10 (Estonia) years later. 1800 participants with valid accelerometer data were analyzed.

Results

MVPA decreased from childhood to adolescence (−1 to −2.5 min/d per year of follow-up, P = 0.01 and <0.001, for girls and boys respectively) and also from adolescence to young adulthood (−0.8 to −2.2 min/d per year, P = 0.02 and <0.001 for girls and boys, respectively). Sedentary time increased from childhood to adolescence (+15 and +20 min/d per year, for girls and boys respectively, P<0.001), with no substantial change from adolescence to young adulthood. Changes in both MVPA and sedentary time were greater in Swedish than in Estonian participants and in boys than in girls. The magnitude of the change observed in sedentary time was 3–6 time larger than the change observed in MVPA.

Conclusions

The decline in MVPA (overall change = 30 min/d) and increase sedentary time (overall change = 2∶45 h/d) observed from childhood to adolescence are of concern and might increase the risk of developing obesity and other chronic diseases later in life. These findings substantially contribute to understand how key health-related behaviors (physical activity and sedentary) change across important periods of life.