Behavioral and Endocrine Consequences of Simultaneous Exposure to Two Different Stressors in Rats: Interaction or Independence?

Although behavioral and endocrine consequences of acute exposure to stressors have been extensively studied, little is known about how simultaneous exposure to two different stressors interacts to induce short- and long-term effects. In the present experiment we studied this interaction in adult male rats exposed to cat fur odor (impregnated cloth) or immobilization on boards either separately or simultaneously. We reasoned that exposure to the odor of a potential predator while immobilized, may potentiate its negative consequences as compared to exposure to only one of the stressors. Exposure to cat odor elicited the expected reduction of activity and avoidance of the area where the impregnated cloth was located. The endocrine response (plasma levels of ACTH and corticosterone, as a measure of the hypothalamic-pituitary-adrenal axis, HPA) was markedly greater after immobilization than after cat fur odor and no additive effects were found by simultaneous exposure to both stressors. Cat odor, but not immobilization, increased anxiety-like behavior as evaluated in the elevated plus-maze 7 days after the stressors, with no evidence of enhanced HPA activation. In addition, cat odor exposure resulted in long-lasting (8 days later) fear conditioning to the box containing a clean cloth, which was reflected by hypoactivity, avoidance of the cloth area and enhanced HPA activation. All these effects were similarly observed in rats exposed simultaneously to cat odor and immobilization. In rats only exposed to immobilization, only some weak behavioral signs of fear conditioning were found, but HPA activation in response to the context paired to immobilization was enhanced to the same extent as in cat odor-exposed animals, supporting a certain degree of endocrine conditioning. The present results did not reveal important behavioral interactions between the two stressors when animals experienced both simultaneously, whereas some interactions were found regarding HPA activation. Theoretical implications are discussed

Temporal origins and diversification of Artemisia and allies (Anthemideae, Asteraceae)

Temporal origins and diversification of Artemisia and allies (Anthemideae, Asteraceae).- To assess temporal origins and diversification of lineages within subtribe Artemisiinae and Artemisia group a penalized likelihood analysis was applied on nrDNA ITS and ETS of 63 representatives. The tree was calibrated at the stem node of the Kaschgaria/Artemisia lineage with the most reliable early Artemisia fossil pollen record from Late Oligocene (23 Ma). The results from this study suggest that the origin of the subtribe goes back to the Late Oligocene (24.6 ± 2.6 Ma) whilst the onset of differentiation of the genus Artemisia and most closely related genera is dated to the Early Miocene (19.8 ± 2.3 Ma). Divergence ages for lineages within the Artemisia group are often between the Early and Middle Miocene, whereas their radiations mostly occurred in the Late Miocene and Pliocene. The temporal context was also used to examine biogeographic and morphological (capitula and pollen type) evolution. Within the Artemisia group all lineages except the North American endemic have colonized the Mediterranean Basin at different epochs from Asian ancestors. Our analyses suggest the divergence of the North American endemic group from Asian ancestors (10.8 ± 1.5 Ma) in the Late Miocene. Homogamous-discoid capitula, characteristic of subgenera Seriphidium and Tridentatae, evolved not only in different geographic regions, but also at different times (2.0 ± 0.8 Ma and 7.9 ± 0.9 Ma respectively) within the Artemisia group. The loss of fertility of central flowers of disciform capitula should be considered as an ancient event in the genus since subgenus Dracunculus is one of the first groups that diverged (17.6 ± 2.1 Ma)

Adecuación del tratamiento de la osteoporosis en prevención primaria. Estudio cuantitativo y cualitativo

Estudio cuantitativo: conocer la prevalencia de inadecuación del tratamiento para la osteoporosis en prevención primaria (OPP) en mujeres de 60-74 años. Estudio cualitativo: conocer los criterios diagnósticos y de tratamiento de la OPP y su variabilidad en médicos de atención primaria (AP) y especialistas. Estudio cuantitativo: estudio observacional, transversal y retrospectivo. Población: mujeres de 60-74 años con tratamiento activo para la OPP (n = 424) en mayo del 2012. Se consideró inadecuación si presentaban ≤ 2 factores de riesgo con DXA realizada o con DXA T-score ≥ −2,4. Estudio cualitativo: técnica Delphi (15 ítems) y dos rondas de consulta. Periodo: marzo-abril del 2014. Población: médicos AP, reumatólogos y traumatólogos (n = 251). Muestreo aleatorio. Estudio cuantitativo: grado de inadecuación del 63,4%. En el 43,2% no constaba diagnóstico de osteoporosis. En el 82,3% no constaban factores de riesgo. Tratamiento: 40,3% con bisfosfonatos y 47,9% con calcio + vitamina D. Estudio cualitativo: el 23% respondieron a la primera ronda y, de estos, el 67% a la segunda ronda. Los ítems con mayor acuerdo fueron valoración de factores de riesgo para el diagnóstico y bisfosfonatos como tratamiento. Los ítems con menor consenso fueron utilización del FRAX y densitometría y tratamiento solo con calcio + vitamina D. El porcentaje de inadecuación es alto. El grado de registro en historia clínica es bajo. La metodología Delphi es útil para detectar discrepancias entre recomendaciones de guías de práctica clínica y resultados

Adecuación del tratamiento de la osteoporosis en prevención primaria. Estudio cuantitativo y cualitativo

Estudio cuantitativo: conocer la prevalencia de inadecuación del tratamiento para la osteoporosis en prevención primaria (OPP) en mujeres de 60-74 años. Estudio cualitativo: conocer los criterios diagnósticos y de tratamiento de la OPP y su variabilidad en médicos de atención primaria (AP) y especialistas. Estudio cuantitativo: estudio observacional, transversal y retrospectivo. Población: mujeres de 60-74 años con tratamiento activo para la OPP (n = 424) en mayo del 2012. Se consideró inadecuación si presentaban ≤ 2 factores de riesgo con DXA realizada o con DXA T-score ≥ −2,4. Estudio cualitativo: técnica Delphi (15 ítems) y dos rondas de consulta. Periodo: marzo-abril del 2014. Población: médicos AP, reumatólogos y traumatólogos (n = 251). Muestreo aleatorio. Estudio cuantitativo: grado de inadecuación del 63,4%. En el 43,2% no constaba diagnóstico de osteoporosis. En el 82,3% no constaban factores de riesgo. Tratamiento: 40,3% con bisfosfonatos y 47,9% con calcio + vitamina D. Estudio cualitativo: el 23% respondieron a la primera ronda y, de estos, el 67% a la segunda ronda. Los ítems con mayor acuerdo fueron valoración de factores de riesgo para el diagnóstico y bisfosfonatos como tratamiento. Los ítems con menor consenso fueron utilización del FRAX y densitometría y tratamiento solo con calcio + vitamina D. El porcentaje de inadecuación es alto. El grado de registro en historia clínica es bajo. La metodología Delphi es útil para detectar discrepancias entre recomendaciones de guías de práctica clínica y resultados

Reproductive development, GnRHa-induced spawning and egg quality of wild meagre (Argyrosomus regius) acclimatised to captivity

The objective of the study was to acclimatise wild-caught meagre (Argyrosomus regius) to captivity to produce viable eggs for aquaculture production. Twelve meagre (3 males and 9 females, mean weight = 20 ± 7 kg) were caught and transported to a land-based facility on 26 October 2006. During, March to June 2007, all three males were spermiating and five of the nine females were in vitellogenesis with mean maximum oocyte diameter ≥550 μm. No spontaneous spawning was observed. Two hormone treatments, either a single injection of gonadotropin-releasing hormone agonist (GnRHa, 20 μg kg−1 for females and 10 μg kg−1 for males) or a slow-release implant loaded with the same GnRHa (50 μg kg−1 for females and 25 μg kg−1 for males), were used to induce spawning on three different dates on 26 March 2007, 4 May 2007 and 18 April 2008. From each spawning event, the following parameters were determined: fecundity, number of floating eggs, egg size, fertilisation and hatching success, unfed larval survival, and proximal composition and fatty acid profile of the eggs. In 2007, two females that were injected on 26 March and 4 May spawned a total of 5 times producing 9,019,300 floating eggs and a relative fecundity of 198,200 eggs kg−1 and two different females that were implanted on the same dates spawned 14 times producing 12,430,000 floating eggs and a relative fecundity of 276,200 eggs kg−1. In 2008, a pair that was implanted spawned five times producing a total of 10,211,900 floating eggs and a relative fecundity of 527,380 eggs kg−1. The latency period was 48–72 h. Parameters were compared between hormone treatments, date of hormone induction and parents determined by microsatellites. Percentage hatch and egg size were 70 ± 0.3% and 0.99 ± 0.02 mm, respectively, for GnRHa-implanted fish and were significantly higher (P < 0.05) compared to 30 ± 0.3% and 0.95 ± 0.03 mm, respectively, for injected fish. Few differences were observed in proximal composition and fatty acid profile and for all spawns mean (% dry weight) lipid content was 17.3 ± 3.0%, carbohydrate was 4.4 ± 1.9% and protein was 31.5 ± 6.4% and the essential fatty acids: Arachidonic acid (ARA, 20:4n-6) ranged between 0.9 and 1% (of total fatty acids), eicosapentaenoic acid (EPA 20:5n-3) 7.7–10.4% and docosahexaenoic acid (DHA 22:6n-3), 28.6–35.4%. All good quality spawns were obtained in the second and/or third spawn after GnRHa treatment, whereas all bad quality spawns were obtained either on the first spawn or after the fifth spawn. Both spawning protocols gave commercially viable (1,000,000+) numbers of good quality eggs that could form the basis of a hatchery production