A summary

Coinciding with the Open Access Week 2010 we publish a study on the perceptions and usage trends amongst CSIC scientific community as regards Open Access in general and CSIC institutional repository in particular.Peer reviewe

Mind the gap: Lücke in der Masern-IgG-Antikörper-Prävalenz bei Kindern unter zwei Jahren in Niedersachsen und Bremen

Säuglinge und Kinder bis zum zweiten Lebensjahr sind eine besonders vulnerable Gruppe für Maserninfektionen. Für sie werden in Deutschland gegenüber anderen Altersgruppen zwei- bis 40-fach höhere Erkrankungsinzidenzen beobachtet und sie sind häufiger von schweren, komplikationsbehafteten Verläufen betroffen. Gegenüber Säuglingen, deren Mütter eine Masernimmunität aufgrund einer Masernwildvirusinfektion erworben haben, ist der Nestschutz bei Säuglingen von ausschließlich durch die Impfung immunisierten Müttern verkürzt. Detaillierte Seroprävalenzdaten für unter Zweijährige lagen in Deutschland jedoch bisher nicht vor. In der vorliegenden Studie wurden Masern-IgG-Antikörperbestimmungen aus den Jahren 2006 bis 2019 von 1.523 Kindern unter zwei Jahren nach Altersgruppen stratifiziert ausgewertet. Es zeigte sich, dass spätestens nach dem 9. Lebensmonat keine maternalen Masern-IgG-Antikörper mehr nachweisbar sind. Die Ergebnisse stützen somit die derzeitige Empfehlung, bei erhöhtem Exposi-tionsrisiko den Zeitpunkt der ersten MMR-Impfung auf neun Monate vorzuverlegen und unterstreichen die Notwendigkeit, Impfquoten insbesondere bei Kleinkindern, aber auch bei jungen Erwachsenen zu steigern.Peer Reviewe

Elevated Plasma Corticosterone Decreases Yolk Testosterone and Progesterone in Chickens: Linking Maternal Stress and Hormone-Mediated Maternal Effects

Despite considerable research on hormone-mediated maternal effects in birds, the underlying physiology remains poorly understood. This study investigated a potential regulation mechanism for differential accumulation of gonadal hormones in bird eggs. Across vertebrates, glucocorticoids can suppress reproduction by downregulating gonadal hormones. Using the chicken as a model species, we therefore tested whether elevated levels of plasma corticosterone in female birds influence the production of gonadal steroids by the ovarian follicles and thus the amount of reproductive hormones in the egg yolk. Adult laying hens of two different strains (ISA brown and white Leghorn) were implanted subcutaneously with corticosterone pellets that elevated plasma corticosterone concentrations over a period of nine days. Steroid hormones were subsequently quantified in plasma and yolk. Corticosterone-implanted hens of both strains had lower plasma progesterone and testosterone levels and their yolks contained less progesterone and testosterone. The treatment also reduced egg and yolk mass. Plasma estrogen concentrations decreased in white Leghorns only whereas in both strains yolk estrogens were unaffected. Our results demonstrate for the first time that maternal plasma corticosterone levels influence reproductive hormone concentrations in the yolk. Maternal corticosterone could therefore mediate environmentally induced changes in yolk gonadal hormone concentrations. In addition, stressful situations experienced by the bird mother might affect the offspring via reduced amounts of reproductive hormones present in the egg as well as available nutrients for the embryo

Corticosterone metabolism by chicken follicle cells does not affect ovarian reproductive hormone synthesis in vitro

<p>Glucocorticoids affect reproductive hormone production in many species. In chickens, elevated plasma corticosterone down-regulates testosterone and progesterone concentrations in plasma, but also in egg yolk. This suppression could be mediated via the hypothalamic-pituitary system but also via local inhibition of gonadal activity by glucocorticoids. As the latter has not been tested in birds yet, we tested if corticosterone directly inhibits ovarian steroid synthesis under in vitro conditions. We hypothesized that degradation of corticosterone by follicular cells impairs their ability to synthesize reproductive hormones due to either inhibition Of enzymes or competition for common co-factors. Therefore, we first established whether follicles degrade corticosterone. Follicular tissue was harvested from freshly euthanized laying hens and incubated with radiolabelled corticosterone. Radioactive metabolites were visualized and quantified by autoradiography. Follicles converted corticosterone in a time-dependent manner into metabolites with a higher polarity than corticosterone. The predominant metabolite co-eluted with 20 beta-dihydrocorticosterone. Other chicken tissues mostly formed the same metabolite when incubated with corticosterone. In a second experiment, follicles were incubated with either progesterone or dehydroepiandrosterone. Corticosterone was added in increasing dosages up to 1000 ng per ml medium. Corticosterone did not inhibit the conversion of progesterone and dehydroepiandrosterone into a number of different metabolites, including 17 alpha-hydroxyprogesterone, androstenedione and testosterone. In conclusion, avian tissues degrade corticosterone mostly to 20 beta-dihydrocorticosterone and even high corticosterone dosages do not affect follicular hormone production under in vitro conditions. (C) 2013 Elsevier Inc. All rights reserved.</p>

Hormone concentrations in yolk after pellet implantation.

<p>Mean (±SE) concentrations of testosterone (a), progesterone (b) and estrogens (c) in yolks from hens implanted with with corticosterone (•) or placebo (○) pellets. Eggs from days 12, 13, 15, 16 and 18 were incubated to hatch chicks. Note that progesterone concentrations are a thousand-fold higher than the other two steroid hormones.</p

Corticosterone concentrations in plasma after pellet implantation.

<p>Mean (± SE) concentrations of corticosterone in plasma of each three hens implanted with 90-day corticosterone release pellets in four different pellet dosages (7.5 mg ○, 15 mg ▾, 20 mg ▪ and 30 mg •).</p

Hormone concentrations in plasma after pellet implantation.

<p>Mean (±SE) concentrations of corticosterone (a), testosterone (b), progesterone (c) in plasma of hens implanted with corticosterone (•) or placebo (○) pellets. Asterisks indicate significant differences between treatments on individual days (_*** p≤0.001; _** p≤0.01; _* p≤0.05; t-tests).</p

Gehäufte Tuberkuloseerkrankungen bei Schlachthofmitarbeitern in Niedersachsen, Ermittlungsergebnisse und Public-Health-Maßnahmen

Seit Anfang 2018 registrierten die Gesundheitsämter in zwei niedersächsischen Landkreisen gehäuft Tuberkulose-Erkrankungen unter Schlachthofmitarbeitern. Insgesamt handelte es sich um 14 Erkrankungen bei Mitarbeitern zweier Schlachthöfe, in denen Schweine geschlachtet und verarbeitet werden. Ein Erkrankter verstarb an den Folgen der Erkrankung. Es folgten z. T. umfassende Umgebungsuntersuchungen durch die Gesundheitsämter. Bei den betroffenen Personen handelte es sich überwiegend um aus Rumänien stammende Arbeitskräfte. Insbesondere die Typisierungsergebnisse der Fälle deuten darauf hin, dass die für die Erkrankungen ursächlichen Infektionen unabhängig voneinander und demzufolge höchstwahrscheinlich nicht im hiesigen Umfeld erworben wurden. Im Epidemiologischen Bulletin 26/2019 werden die aus Sicht des Infektionsschutzes sich ergebenden Ansatzpunkte für Public-Health-Maßnahmen diskutiert.Peer Reviewe

Maternal corticosterone elevation during egg formation in chickens (Gallus gallus domesticus) influences offspring traits, partly via prenatal undernutrition

<p>The relationship between maternal stress during pregnancy in humans and the subsequent physical and mental health disorders in their children has inspired a wide array of studies on animal models. Almost all of these studies have used mammalian species, but more recently oviparous species in which the embryo develops outside the mother's body have received more attention. These new models facilitate disentangling of the underlying mechanism due to the accessibility of the prenatal environment, the egg. Studies in birds have found that maternal stress during egg formation induces phenotypic alterations in the offspring that hatch from these eggs. However, different offspring traits have been measured in different studies and potential underlying mechanisms are barely addressed. In this study we experimentally manipulated maternal corticosterone levels in laying hens. We found that mothers with experimentally elevated plasma corticosterone levels produced offspring that are smaller at hatching, less competitive, less fearful, have lower immunocompetence and higher plasma testosterone levels, as well as an alteration of visually guided behavioural lateralization. Earlier we have showed that eggs produced by these corticosterone treated mothers were lighter and contained lower concentrations of testosterone and progesterone in the yolk. While yolk hormones showed no correlation with any offspring traits, egg mass correlated positively with offspring's body mass from hatching until 10 days of age and hatching mass correlated positively with the offspring's ability to compete for food, indicating that prenatal under nutrition might mediate some effects of maternal stress. (C) 2013 Elsevier Inc. All rights reserved.</p>