Circadian clock genes, ovarian development and diapause

Insects, like most organisms, have an internal circadian clock that oscillates with a daily rhythmicity, and a timing mechanism that mediates seasonal events, including diapause. In research published in BMC Biology, Ikeno et al. show that downregulation of the circadian clock genes period and cycle affects expression of ovarian diapause in the insect Riptortus pedestris. They interpret these important results as support for Erwin Bünning's (1936) hypothesis that the circadian clock constitutes the basis of photoperiodism. However, their observations could also be the result of pleiotropic effects of the individual clock genes

Generation of induced pluripotent stem cells from three individuals with Huntington's disease

Huntington's disease (HD) is a neurodegenerative disorder caused by abnormal glutamine (Q) expansion in the huntingtin protein due to elongated CAG repeats in the gene HTT. We used non-integrative episomal plasmids to generate induced pluripotent stem cells (iPSCs) from three individuals affected by HD: CH1 (58Q), and two twin brothers CH3 (44Q) and CH4 (44Q). The iPSC lines exhibited one healthy HTT allele and one with elongated CAG repeats, as confirmed by PCR and sequencing. All iPSC lines expressed pluripotency markers, exhibited a normal karyotype, and generated cells of the three germ layers in vitro

Generation of four iPSC lines from four patients with Leigh syndrome carrying homoplasmic mutations m.8993T > G or m.8993T > C in the mitochondrial gene MT-ATP6.

We report the generation of four human iPSC lines (8993-A12, 8993-B12, 8993-C11, and 8993-D7) from fibroblasts of four patients affected by maternally inherited Leigh syndrome (MILS) carrying homoplasmic mutations m.8993T > G or m.8993T > C in the mitochondrial gene MT-ATP6. We used Sendai viruses to deliver reprogramming factors OCT4, SOX2, KLF4, and c-MYC. The established iPSC lines expressed pluripotency markers, exhibited a normal karyotype, were capable to form cells of the three germ layers in vitro, and retained the MT-ATP6 mutations at the same homoplasmic level of the parental fibroblasts

Infrared method for determining circadian patterns of carbon dioxide release

Using an infrared technique based on the continuous monitoring of a characteristic infrared absorption band, temporal variations in the circadian patterns of carbon dioxide release were examined in two species of noctuid moths, the corn earworm Heliothis zea ( Boddie ) and the fall armyworm Spodoptera frugiperda ( J. E. Smith ). The detailed emission patterns were shown to be different in the two moth species (Figs. 3, 4). Emission patterns similar to those obtained in adults were also observed to be present in the pupal stage of development.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47098/1/359_2004_Article_BF00302280.pd

Linking formal child care characteristics to children's socioemotional well-being: A comparative perspective

Most research on formal child care and children’s outcomes has focused on single countries. We, however, contend that policy context may moderate the association between formal child care characteristics and children’s socioemotional well-being. We examined this by comparing the Netherlands, Finland and the UK; three countries that differ regarding family policies. Of these three countries, Finland was recently ranked highest (ranked 1st) with regards to quality of child care in a recent analysis by the Economist ,followed by the UK (ranked 3rd) and then the Netherlands (ranked 7th) .We hypothesized that children who attend child - care settings in countries with higher- uality formal child- are provision would generally show better socioemotional outcomes. Data from the comparative ‘F amilies 24/7’ survey were used, including 990 parents with children aged 0–12. We distinguished between two age groups in our analysis. Results indicated that, compared to the UK, longer hours in formal care were less beneficial in the Netherlands. Furthermore, spen ding time in formal care during nonstandard hours was more harmful for children in Finland compared to the UK. Lastly, receiving care from multiple caregivers was more disruptive for British children than for Dutch children. No differences were found between Finland and the Netherlands

Aldehydes phase shift the Gonyaulax clock

Aliphatic aldehydes ranging in chain length from one to four carbon atoms have a significant phase shifting effect upon the circadian rhythm of bioluminescence (glow) in the dinoflagellate ( Gonyaulax polyedra . Cells exposed for two hours to 18 mM acetaldehyde starting at about circadian time 12 experience a permanent phase delay of up to about 12 h. The phase response curve relationship with acetaldehyde is presented, as well as the relationship between concentration and phase delay for the four aldehydes studied. Reactions of aldehydes which may be implicated are discussed. The possibility that sulfhydryl reagents generally may perturb circadian systems is suggested.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47121/1/360_2004_Article_BF00689855.pd

Social and health epidemiology of immigrants in Germany: past, present and future

Razum O, Wenner J. Social and health epidemiology of immigrants in Germany: past, present and future. Public Health Reviews. 2016;37(1): 4.Germany has experienced different forms of immigration for many decades. At the end of and after the Second World War, refugees, displaced persons and German resettlers constituted the largest immigrant group. In the 1950s, labor migration started, followed by family reunification. There has been a constant migration of refugees and asylum seekers reaching peaks in the early 1990s as well as today. Epidemiological research has increasingly considered the health, and the access to health care, of immigrants and people with migration background. In this narrative review we discuss the current knowledge on health of immigrants in Germany. The paper is based on a selective literature research with a focus on studies using representative data from the health reporting system. Our review shows that immigrants in Germany do not suffer from different diseases than non-immigrants, but they differ in their risk for certain diseases, in the resources to cope with theses risk and regarding access to treatment. We also identified the need for differentiation within the immigrant population, considering among others social and legal status, country of origin and duration of stay. Though most of the studies acknowledge the need for differentiation, the lack of data currently rules out analyses accounting for the existing diversity and thus a full understanding of health inequalities related to migration to Germany

Die Vereinbarkeitsfrage für Männer: Welche Auswirkungen haben Elternzeiten und Teilzeitarbeit auf die Stundenlöhne von Vätern?

Studien zeigen, dass sich viele Väter in Deutschland wünschen, mehr Zeit mit ihren Kindern zu verbringen, dies aufgrund von langen Arbeitszeiten jedoch oft nicht umsetzen können. Elternzeit und Teilzeitarbeit könnten Optionen sein, die Vätern eine bessere Vereinbarkeit von Familie und Beruf ermöglichen. Arbeitsmarkttheorien legen jedoch nahe, dass die Inanspruchnahme solcher Maßnahmen mit Lohneinbußen verbunden ist. Dementsprechend entscheiden sich derzeit viele Väter gegen diese Möglichkeiten zur Vereinbarkeit von Familie und Beruf, da sie finanzielle Einbußen und Karrierenachteile befürchten. Um zu überprüfen, inwieweit diese Erwartungen empirisch fundiert sind, untersucht diese Arbeit daher den Einfluss von Elternzeit und Teilzeitarbeit auf die Stundenlöhne von Vätern. Fixed Effects-Analysen auf Basis des Sozio-oekonomischen Panels (SOEP) 1991-2013 und Familien in Deutschland (FiD) 2010-2013 zeigen, dass Teilzeitarbeit mit Lohneinbußen verbunden ist. Eine Elternzeit wirkt sich hingegen nicht auf die Löhne von Vätern aus - unabhängig davon, ob Väter nur die beiden für sie reservierten Partnermonate oder eine längere Elternzeit in Anspruch nehmen. Die Ergebnisse deuten somit darauf hin, dass die gesetzliche Elternzeit Vätern einen Rahmen bietet, in dem sie sich stärker in ihren Familien engagieren können, ohne berufliche Nachteile zu erfahren.As previous research shows, many German fathers would like to spend more time with their children, but long working hours often restrict their opportunities to do so. Parental leave and part-time work could help fathers to reconcile work and family. Yet, labor market theories predict that using such family-friendly policies may lead to wage penalties. Hence, many fathers decide against using such policies because they fear that parental leave or part-time work will lead to financial penalties and career disadvantages. This article evaluates this concern by empirically examining the effect of parental leave and part-time work on fathers’ hourly wages. Using data from the German Socio-Economic Panel (SOEP) 1991-2013 and Families in Germany (FiD) 2010-2013, results from fixed-effects regression analyses show that part-time work is associated with wage penalties, but parental leave is not - irrespective of whether fathers only took the two months fathers’ quota or longer parental leaves. The results hence indicate that the German parental leave legislation enables fathers to spend more time with their children while protecting them from wage penalties at work

Circadian clock mechanism driving mammalian photoperiodism.

The annual photoperiod cycle provides the critical environmental cue synchronizing rhythms of life in seasonal habitats. In 1936, Bünning proposed a circadian-basis for photoperiodic synchronization. Here, light-dark cycles entrain a circadian rhythm of photosensitivity, and the expression of summer or winter biology depends on whether light coincides with the phase of high photosensitivity. Formal studies support the universality of this so-called coincidence timer, but we lack understanding of the mechanisms involved. Here we show in mammals that coincidence timing takes place in the pars tuberalis of the pituitary, through a melatonin-dependent flip-flop switch between circadian transcriptional activation and repression. Long photoperiods produce short night-time melatonin signals, leading to induction of the circadian transcription factor BMAL2, in turn triggering summer biology through the eyes absent / thyrotrophin (EYA3 / TSH) pathway. Conversely, short photoperiods produce long melatonin signals, inducing circadian repressors including DEC1, in turn suppressing BMAL2 and the EYA3/TSH pathway, triggering winter biology. These actions are associated with progressive genome-wide changes in chromatin state, elaborating the effect of the circadian coincidence timer. Hence, circadian clock interactions with pituitary epigenetic pathways form the basis of the mammalian coincidence timer mechanism. Our results constitute a blueprint for circadian-based seasonal timekeeping in vertebrates