Warm temperature acclimation impacts metabolism of paralytic shellfish toxins from Alexandrium minutum in commercial oysters

© 2015 John Wiley & Sons Ltd. Species of Alexandrium produce potent neurotoxins termed paralytic shellfish toxins and are expanding their ranges worldwide, concurrent with increases in sea surface temperature. The metabolism of molluscs is temperature dependent, and increases in ocean temperature may influence both the abundance and distribution of Alexandrium and the dynamics of toxin uptake and depuration in shellfish. Here, we conducted a large-scale study of the effect of temperature on the uptake and depuration of paralytic shellfish toxins in three commercial oysters (Saccostrea glomerata and diploid and triploid Crassostrea gigas, n = 252 per species/ploidy level). Oysters were acclimated to two constant temperatures, reflecting current and predicted climate scenarios (22 and 27 °C), and fed a diet including the paralytic shellfish toxin-producing species Alexandrium minutum. While the oysters fed on A. minutum in similar quantities, concentrations of the toxin analogue GTX1,4 were significantly lower in warm-acclimated S. glomerata and diploid C. gigas after 12 days. Following exposure to A. minutum, toxicity of triploid C. gigas was not affected by temperature. Generally, detoxification rates were reduced in warm-acclimated oysters. The routine metabolism of the oysters was not affected by the toxins, but a significant effect was found at a cellular level in diploid C. gigas. The increasing incidences of Alexandrium blooms worldwide are a challenge for shellfish food safety regulation. Our findings indicate that rising ocean temperatures may reduce paralytic shellfish toxin accumulation in two of the three oyster types; however, they may persist for longer periods in oyster tissue

Transient Receptor Potential Ion Channels Control Thermoregulatory Behaviour in Reptiles

Biological functions are governed by thermodynamics, and animals regulate their body temperature to optimise cellular performance and to avoid harmful extremes. The capacity to sense environmental and internal temperatures is a prerequisite for the evolution of thermoregulation. However, the mechanisms that enable ectothermic vertebrates to sense heat remain unknown. The recently discovered thermal characteristics of transient receptor potential ion channels (TRP) render these proteins suitable to act as temperature sensors. Here we test the hypothesis that TRPs are present in reptiles and function to control thermoregulatory behaviour. We show that the hot-sensing TRPV1 is expressed in a crocodile (Crocodylus porosus), an agamid (Amphibolurus muricatus) and a scincid (Pseudemoia entrecasteauxii) lizard, as well as in the quail and zebrafinch (Coturnix chinensis and Poephila guttata). The TRPV1 genes from all reptiles form a unique clade that is delineated from the mammalian and the ancestral Xenopus sequences by an insertion of two amino acids. TRPV1 and the cool-sensing TRPM8 are expressed in liver, muscle (transversospinalis complex), and heart tissues of the crocodile, and have the potential to act as internal thermometer and as external temperatures sensors. Inhibition of TRPV1 and TRPM8 in C. porosus abolishes the typically reptilian shuttling behaviour between cooling and heating environments, and leads to significantly altered body temperature patterns. Our results provide the proximate mechanism of thermal selection in terrestrial ectotherms, which heralds a fundamental change in interpretation, because TRPs provide the mechanism for a tissue-specific input into the animals' thermoregulatory response

Gestaltung von Anpassungspfaden im Klimarisikomanagement. Leitfaden für Entscheidungsträgerinnen und Entscheidungsträger

Entscheidungen im lokalen Management von klimabedingten Risiken, wie z.B. im Hochwasserrisikomanagement, erfolgen regelmäßig sehr rasch nach einem Ereignis, u.a. auch aufgrund massiven Drucks der lokalen Bevölkerung. Dabei werden meist Maßnahmen umgesetzt, die allgemein bekannt sind und dem Stand der Technik entsprechen. Diese singulären und sich an der Vergangenheit orientierenden Entscheidungen führen aber dazu, dass sich das Schadenspotential in den Gemeinden und Regionen meist weiterentwickelt und den zukünftigen Herausforderungen im Risikomanagement aufgrund des Klimawandels nur unzureichend genügt. Deshalb ist es wichtig, aktuelle Pfadabhängigkeiten frühzeitig zu erkennen und eine Entkoppelung davon zu erzielen. Nur so kann ein antizipatives Klimarisikomanagement umgesetzt und verstetigt werden, welches auch über einzelne klimabedingte Risiken hinweg agiert. Der Leitfaden „Gestaltung von Anpassungspfaden im Klimarisikomanagement“ dient als mögliche Erweiterung des „Vorsorgechecks Naturgefahren im Klimawandel“, welcher den Status Quo aller in einer Gemeinde möglichen Naturgefahren abhandelt. Dieser Leitfaden richtet sich somit vorrangig an jene österreichischen Gemeinden, die entweder bereits einen solchen „Naturgefahrencheck“ absolviert haben oder dies in Zukunft noch vorhaben. Der Leitfaden schlägt fünf konkrete Schritte vor, um im Anschluss an die Methodik des Naturgefahrenchecks (1) das Bewusstsein für die Zusammenhänge zwischen einzelnen klimabedingten Risiken zu schärfen, (2) aus den bisher gemachten Erfahrungen im Naturgefahrenmanagement für die „neuen“ Risiken zu lernen und (3) gemeinsam konkrete Maßnahmen zu entwerfen und nächste Umsetzungsschritte zu definieren, wie diese Risiken in Zukunft zusammen gedacht und proaktiv angegangen werden können. Der Leitfaden ist so aufgebaut, dass bei Bedarf auch jeder Schritt als einzelnes gesondertes Erweiterungsmodul für den „Vorsorgechecks Naturgefahren im Klimawandel“ dienen kann

Unexpected ring‑opening of 2,3‑dihydropyridines

The reaction of 2,3-dihydropyridines with sulfonyl halides surprisingly yielded open chain dienes with sulfonylimine structure. The products were specific out of several possible isomers and, therefore, a separation of isomers was not necessary. All new compounds were characterized using FT-IR spectroscopy, HRMS, and NMR spectroscopy. A bicyclic by-product from the reaction of a 2,3-dihydropyridine with mesyl chloride was isolated and its structure elucidated using a single X-ray crystal analysis. Some biological activities, like antimicrobial and cytotoxic properties were investigated

ICC-CLASS: isotopically-coded cleavable crosslinking analysis software suite

<p>Abstract</p> <p>Background</p> <p>Successful application of crosslinking combined with mass spectrometry for studying proteins and protein complexes requires specifically-designed crosslinking reagents, experimental techniques, and data analysis software. Using isotopically-coded ("heavy and light") versions of the crosslinker and cleavable crosslinking reagents is analytically advantageous for mass spectrometric applications and provides a "handle" that can be used to distinguish crosslinked peptides of different types, and to increase the confidence of the identification of the crosslinks.</p> <p>Results</p> <p>Here, we describe a program suite designed for the analysis of mass spectrometric data obtained with isotopically-coded <it>cleavable </it>crosslinkers. The suite contains three programs called: DX, DXDX, and DXMSMS. DX searches the mass spectra for the presence of ion signal doublets resulting from the light and heavy isotopic forms of the isotopically-coded crosslinking reagent used. DXDX searches for possible mass matches between cleaved and uncleaved isotopically-coded crosslinks based on the established chemistry of the cleavage reaction for a given crosslinking reagent. DXMSMS assigns the crosslinks to the known protein sequences, based on the isotopically-coded and un-coded MS/MS fragmentation data of uncleaved and cleaved peptide crosslinks.</p> <p>Conclusion</p> <p>The combination of these three programs, which are tailored to the analytical features of the specific isotopically-coded cleavable crosslinking reagents used, represents a powerful software tool for automated high-accuracy peptide crosslink identification. See: <url>http://www.creativemolecules.com/CM_Software.htm</url></p

The presence of postmenopausal bleeding as prognostic parameter in patients with endometrial cancer: a retrospective multi-center study

Abstract Background To date, there is no consensus on the utility of screening procedures for the early detection of endometrial cancer. The value of transvaginal ultrasound for screening of asymptomatic endometrial cancer has been discussed controversially. This study was conducted to evaluate whether asymptomatic patients with endometrial cancer have a better prognosis than symptomatic patients with endometrial cancer diagnosed after postmenopausal bleeding. Methods In the present multi-center study, the effect of the presence of postmenopausal bleeding on prognosis was evaluated retrospectively in 605 patients with endometrial cancer using patients' files. 543 patients (133 patients were asymptomatic, 410 patients were symptomatic) with endometrioid endometrial cancer were enrolled in all further analysis. Student's t-test, Cox regression analysis and Kaplan-Meier analysis were used were appropriate. Results Presence/absence of a postmenopausal bleeding was not associated with tumor stage (p = 0.2) and age at diagnosis (p = 0.5). Asymptomatic patients with endometrial cancer had a significantly higher rate of well and moderate-differentiated tumors compared to symptomatic patients (p = 0.008). In univariable and multivariable survival analysis, tumor stage, tumor grade, and patients' age at diagnosis, but not presence/absence of a postmenopausal bleeding, were associated with disease free and overall survival. Conclusion Asymptomatic patients with endometrial cancer have a higher rate of well differentiated tumors compared to patients with a postmenopausal bleeding prior to diagnosis. The prognosis of both groups of patients was similar.</p