Healthily Nourished but Depleted? Is It Possible to Improve the Health of Shift Workers through Lifestyle Interventions?

The relationship between diet and health is well-researched, and there is also information regarding the effects of diet on mental health. This study aimed to investigate whether motivation to optimize lifestyles without regulations or restrictions could improve the health of rotating shift workers. In this pilot study, 18 male shift workers were randomly divided into two groups. All participants completed the Short Form Health Survey-36 questionnaire (SF-36) before the start and at the end of the study. Group I (n = 9, mean age 42 ± 6.6 y) received dietary and lifestyle information every other month for one year, and the other, Group II (n = 9 mean age 36 ± 7.3 y), one year later. All participants were motivated to follow the trained dietary recommendations and to engage in physical activity. Almost all scores had improved. Surprisingly, physical performance scores worsened, which was not expected. The impairment in mental health due to the change in ownership of the company could have been better explained. Nutritional advice over a longer period and the motivation to integrate more exercise into everyday life can potentially improve the health of rotating shift workers

Prolonged hypoxia increases survival even in Zebrafish (Danio rerio) showing cardiac arrhythmia.

Tolerance towards hypoxia is highly pronounced in zebrafish. In this study even beneficial effects of hypoxia, specifically enhanced survival of zebrafish larvae, could be demonstrated. This effect was actually more pronounced in breakdance mutants, which phenotypically show cardiac arrhythmia. Breakdance mutants (bre) are characterized by chronically reduced cardiac output. Despite an about 50% heart rate reduction, they become adults, but survival rate significantly drops to 40%. Normoxic bre animals demonstrate increased hypoxia inducible factor 1 a (Hif-1α) expression, which indicates an activated hypoxic signaling pathway. Consequently, cardiovascular acclimation, like cardiac hypertrophy and increased erythrocyte concentration, occurs. Thus, it was hypothesized, that under hypoxic conditions survival might be even more reduced. When bre mutants were exposed to hypoxic conditions, they surprisingly showed higher survival rates than under normoxic conditions and even reached wildtype values. In hypoxic wildtype zebrafish, survival yet exceeded normoxic control values. To specify physiological acclimation, cardiovascular and metabolic parameters were measured before hypoxia started (3 dpf), when the first differences in survival rate occurred (7 dpf) and when survival rate plateaued (15 dpf). Hypoxic animals expectedly demonstrated Hif-1α accumulation and consequently enhanced convective oxygen carrying capacity. Moreover, bre animals showed a significantly enhanced heart rate under hypoxic conditions, which reached normoxic wildtype values. This improvement in convective oxygen transport ensured a sufficient oxygen and nutrient supply and was also reflected in the significantly higher mitochondrial activity. The highly optimized energy metabolism observed in hypoxic zebrafish larvae might be decisive for periods of higher energy demand due to organ development, growth and increased activity. However, hypoxia increased survival only during a short period of development and starting hypoxia before or after this phase reduced survival, particularly in bre animals. Thus, the physiological plasticity, which enables zebrafish larvae to benefit from a hypoxia, occurs only within a narrow developmental window

Orientation-Dependent Reflection of Structurally Coloured Butterflies

The photonic structures of butterfly wing scales are widely known to cause angle-dependent colours by light interference with nanostructures present in the wing scales. Here, we quantify the relevance of the horizontal alignment of the butterfly wing scales on the wing. The orientation-dependent reflection was measured at four different azimuth angles, with a step size of 90°, for ten samples—two of different areas of the same species—of eight butterfly species of three subfamilies at constant angles of illumination and observation. For the observed species with varying optical structures, the wing typically exhibits higher orientation-dependent reflections than the individual scale. We find that the measured anisotropy is caused by the commonly observed grating structures that can be found on all butterfly wing scales, rather than the local photonic structures. Our results show that the technique employed here can be used to quickly evaluate the orientation-dependence of the reflection and hence provide important input for bio-inspired applications, e.g., to identify whether the respective structure is suitable as a template for nano-imprinting techniques

Microarray analysis.

<p>Comparison of mRNA expression of 3 and 7 dpf old normoxic control or <i>bre</i> larvae. Transcripts, which were up or down-regulated in control as well as <i>bre</i> animals, are listed.</p

mRNA expression levels.

<p><i>pdk2</i> (A) and <i>ucp1</i> (B) mRNA expression of control and <i>bre</i> larvae developing under normoxic or hypoxic conditions. Data are shown as mean ± SE. Significance versus normoxic control is marked with *.</p

Western blot analysis.

<p>AMPK protein expression of control and <i>bre</i> larvae developing under normoxic or hypoxic conditions presenting the percentage of pAMPK in the overall AMPK protein expression. Data are shown as mean ± SE. Significance versus normoxic control is marked with *. Significant differences between all other groups are listed in the table.</p

Activity profiles.

<p>Total daily activity of 3 to 7<i>bre</i> larvae developing under normoxic or hypoxic conditions (A). Body length of control and <i>bre</i> larvae developing under normoxic or hypoxic conditions (B). Data are shown as mean ± SE. Significance versus normoxic control is marked with *. Significant differences between all other groups are listed in the table.</p

Statistical analysis of NileRed staining.

<p>p-values of the chi square test analyzing lipid staining with NileRed. Significance versus normoxic control is marked with bold values. Numbers regarding heart, mandibular area and droplets indicate occurrence of red signaling, intestine and liver indicate preference of red or green signaling.</p