On the enigmatic scent glands of dyspnoan harvestmen (Arachnida, Opiliones): first evidence for the production of volatile secretions

La utilización en encuestas de preguntas con tarjetas de respuesta está totalmente aceptada por la comunidad investigadora. Esto supone una carga de trabajo “extra” en la tarea del entrevistador, lo que explica que en ocasiones no se utilicen correctamente. Pese a esta situación, hay muy poca literatura sobre la influencia de las tarjetas en las respuestas del entrevistado. El objetivo de este trabajo es profundizar en los efectos que la utilización de tarjetas tiene en la calidad de las respuestas del cuestionario, partiendo de la hipótesis que considera que las tarjetas —pese a complicar la tarea del encuestador— suponen importantes mejoras en la administración del cuestionario. Utilizaremos para ello un estudio del Centro de Investigaciones Sociológicas con 23 preguntas de tarjeta, comparando las respuestas de los entrevistados que utilizaron las tarjetas con aquellos que no las emplearon.Using “response cards” in question surveys is unanimously approved by the research community. The fact that this represents an extra workload for the interviewer’s task explains why they sometimes are not used correctly. Despite this situation there is a paucity of literature on the influence of the response card on the respondent’s answers. The aim of this study is to deepen the analysis of how using these cards affect the quality of the survey’s responses. To do so, we start from the assumption that the cards —while complicating the interviewer’s task, result in significant improvements in the survey’s administration. For this purpose we will use a study with 23 card questions (question cards) by the Centro de Investigaciones Sociológicas, (the Spanish Centre for Sociological Research), and we will compare the answers of respondents that used cards with those who did not

A Novel Class of Defensive Compounds in Harvestmen: Hydroxy-γ-Lactones from the Phalangiid Egaenus convexus

When threatened, the harvestman Egaenus convexus (Opiliones: Phalangiidae) ejects a secretion against offenders. The secretion originates from large prosomal scent glands and is mainly composed of two isomers of 4-hydroxy-5-octyl-4,5-dihydro-3H-furan-2-one (1), a β-hydroxy-γ-lactone. The compounds were characterized by GC-MS of their microreaction derivatives, HRMS, and NMR. After the synthesis of all four possible stereoisomers of 1, followed by their separation by chiral-phase GC, the absolute configurations of the lactones in the Egaenus secretion was found to be (4S,5R)-1 (90%) and (4S,5S)-1 (10%). Hydroxy-γ-lactones represent a new class of exocrine defense compounds in harvestmen

Chrysomelidial in the Opisthonotal Glands of the Oribatid Mite, Oribotritia berlesei

Gas chromatographic–mass spectrometric analyses of whole body extracts of Oribotritia berlesei, a large-sized soil-dwelling oribatid mite, revealed a consistent chemical pattern of ten components, probably originating from the well-developed opisthonotal glands. The three major components of the extract were the iridoid monoterpene, (3S,8S)-chrysomelidial (about 45% of the extract), the unsaturated hydrocarbon 6,9-heptadecadiene, and the diterpene β-springene (the latter two, each about 20–25% of the extract). The remaining minor components (together about 10% of the extract) included a series of hydrocarbons (tridecene, tridecane, pentadecene, pentadecane, 8-heptadecene, and heptadecane) and the tentatively identified 9,17-octadecadienal. In contrast, analysis of juveniles showed only two compounds, namely a 2:1 mixture of (3S,8S)-chrysomelidial and its epimer, epi-chrysomelidial (3S,8R-chrysomelidial). Unexpectedly, neither adult nor juvenile secretions contained the so-called astigmatid compounds, which are considered characteristic of secretions of oribatids above moderately derived Mixonomata. The chrysomelidials, as well as β-springene and octadecadienal, are newly identified compounds in the opisthonotal glands of oribatid mites and have chemotaxonomic potential for this group. This is the first instance of finding chrysomelidials outside the Coleoptera

Ionomycin induces prostaglandin E2 formation in murine osteoblastic MC3T3-E1 cells via mechanisms independent of its ionophoric nature

Ionomycin and A23187 are divalent cation ionophores with a marked preference for calcium. Studies using these ionophores have been almost exclusevly interpreted their results in the light of calcium elevation. It was the aim of this study to investigate effects of ionomycin in osteoblatic MC3T3-E1 cells that are not attributable to its ionophoric properties. Thus, we have found that, in contrast to A23187, ionomycin shows similar effects on prostaglandin E2 formation as bradykinin and endothelin-1, being potentiated by extracellular nickel and inhibited by cholera toxin and pertussis toxin. Our data strongly suggest that inomycin, at least in part, exerts its effects via specific binding to a G-protein coupled receptor, thereby evoking downstreams cellular events like arachidonate release with subsequent prostaglandin formation.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author