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They also represent an important component of the ocean's biota and contribute significantly to global carbon fluxes. Coccolithophores produce intricate calcite scales (coccoliths) internally that they secrete onto their external surface. This review presents some recent key findings on the mechanisms underlying the production of coccoliths. It also considers the factors that regulate the rate of production as well as the variety of shapes of individual coccoliths and their arrangements at the cell surface. Understanding these processes is needed to allow better predictions of how coccolithophores may respond to changing ocean chemistry associated with climate change.The osmorespiratory compromise hypothesis posits that respiratory epithelial characteristics and physiological regulatory mechanisms which promote gas permeability also increase permeability to ions and water. The hypothesis therefore predicts that physiological responses which increase effective gas permeability will result in increased effective ion and water permeabilities. Though analyses of water and gas effective permeabilities using high temperature have generally supported the hypothesis, water permeability responses to hypoxia remain equivocal and the combination of high temperature and hypoxia untested. We measured diffusive water flux (DWF) and oxygen uptake rate (Ṁo2) in response to acute temperature change, hypoxia, and the combination of high temperature and hypoxia in a hypoxia-tolerant intertidal fish, the tidepool sculpin (Oligocottus maculosus). In support of the osmorespiratory compromise hypothesis, Ṁo2 and DWF increased with temperature. In contrast, DWF decreased with hypoxia at a constant temperature, a result consistent with previously observed decoupling of water and gas effective permeabilities during hypoxia exposure in some hypoxia tolerant fishes. However, DWF levels during simultaneous high temperature and hypoxia exposure were not different from fish exposed to high temperature in normoxia, possibly suggesting a failure of the mechanism responsible for down-regulating DWF in hypoxia. These results, together with time-course analysis of hypoxia exposure and normoxic recovery, suggest that tidepool sculpins actively downregulate effective water permeability in hypoxia but the mechanism fails with multi-stressor exposure. Future investigations of the mechanistic basis of the regulation of gill permeability will be key to understanding the role of this regulatory ability in the persistence of this species in the dynamic intertidal environment.Respiratory acidosis and subsequent metabolic compensation are well-studied processes in fish exposed to elevated CO2 (hypercapnia). Yet, such exposures in the marine environment are invariably accompanied by a return of environmental CO2 to atmospheric baselines. This understudied phenomenon has the potential to cause a respiratory alkalosis that would necessitate base excretion. Here we sought to explore this question and the associated physiological mechanisms that may accompany base excretions using the red drum (Sciaenops ocellatus). As expected, when high pCO2 (15,000 μatm CO2) acclimated red drum were transferred to normal pCO2, their net H+ excretion shifted from positive (0.157 ± 0.044 μmol g-1 h-1) to negative (-0.606 ± 0.116 μmol g-1 h-1) in the 2 h post-transfer period. Net H+ excretion returned to control rates during the 3 to 24 h flux period. Gene expression and enzyme activity assays demonstrated that while the acidosis resulted in significant changes in several relevant transporters, no significant changes accompanied the alkalosis phase. Confocal microscopy was used to assess alkalosis-stimulated translocation of V-type H+ ATPase to the basolateral membrane previously seen in other marine species; however, no apparent translocation was observed. Overall, these data demonstrate that fluctuations in environmental CO2 result in both acidic and alkalotic respiratory disturbances; however, red drum maintain sufficient regulatory capacity to accommodate base excretion. Furthermore, this work does not support a role for basolateral VHA translocation in metabolic compensation from a systemic alkalosis in teleosts.In this work, we present a gas-chromatography tandem mass spectrometry (GC-MS/MS) method for the identification of the sulfo-conjugate metabolites of pseudo-endogenous steroids (endogenous steroids when administered exogenously). We have preliminarily evaluated the performances of different preparations of sulfatases from Pseudomonas aeruginosa and Helix pomatia, characterized by various origins and catalytic activities, and compared the efficacy of the enzymatic hydrolysis with chemical hydrolysis, performed with a mixture of ethyl acetate, methanol, and sulphuric acid. Nanchangmycin A procedure for the selective isolation of steroid conjugates from the urine matrix has been designed and optimized, based on the "sequential" extraction of the glucuro-conjugated and of the sulfo-conjugated fractions, performed by two different direct methods, i.e. by ion paired extraction or solid-phase extraction. More specifically, the former method is based on the use of N,N-dimethylephedrinium bromide as the ion paired extraction reagent, while the latter on the use of WAX® (weak anion exchange) cartridges. The performance of the newly developed procedure has been assessed by the analysis of real urine excretion samples collected after the oral intake of a single dose of dehydroepiandrosterone (DHEA) or androstenedione (AED), measuring the concentration of epiandrosterone (EpiA) sulfate. Our results have shown the following (i) although the yields of chemical hydrolysis and enzymatic hydrolysis are in some cases quite similar, the former is generally preferable since it results in the quantitative cleavage of sulfate moiety; (ii) ion paired extraction has been selected as the most reliable method for direct isolation of sulfate steroids from urine matrices; (iii) EpiA sulfate allows to prolong the detectability of DHEA and AED when compared to routinely used steroidal target compounds.Lipomax is a commercialized foldase-dependent Pseudomonas lipase that was previously expressed only in Pseudomonas strains. Here, using Pichia pastoris as the host, we report a new co-expression method that leads to the successful production of Lipomax. The active Lipomax is extracellularly co-expressed with its cognate foldase (LIM); and the purified enzyme mix has the optimum pH at pH 8.0 and an optimal temperature around 40 °C. N-glycosylation was observed for Pichia produced Lipomax, and its reduction was shown to increase the lipolytic activity. With different p-nitrophenyl esters as the substrates, the substrate profiling analyses further indicate that Lipomax prefers esters with middle-long chain fatty acids, showing the highest specific activity to p-nitrophenyl caprylate (C8). The extracellular co-expression of Lipomax and LIM in Pichia will not only increase our ability to investigate additional eukaryotic hosts for lipase expression, but also be of considerable value in analyzing other foldase-dependent lipases.Herein we describe our efforts to develop novel anti-inflammatory/analgesic agents devoid of known cardiovascular drawbacks. In doing so, two 1,5-diarylpyrazole series of urea linked (9a-f) and amide linked (11a-f) compounds were synthesized and evaluated in vitro as dual COX-2/sEH inhibitors using recombinant enzyme assays. The in vivo anti-inflammatory and analgesic activities were then examined using reported animal models. Compounds 9b and 9c showed the highest inhibitory activities against both COX-2 and sEH (IC50 of COX-2 = 1.85 and 1.24 μM; sEH = 0.55 and 0.40 nM, respectively), besides showing the best activity as anti-inflammatory agents. Interestingly, the cardiovascular profile of the two compounds 9b and 9c was evaluated through measuring some biochemical parameters such as prostacyclin (PGI2), lactate dehydrogenase (LDH), troponin-1 (Tn-1), tumor necrosis factor- α (TNF-α), creatine kinase-M (CK-M) and reduced glutathione (GSH) in addition to a histo-pathological study to investigate the changes in the heart muscle. The results confirmed that compounds 9b and 9c have a more favorable cardio-profile than celecoxib with much less cardiovascular risks associated with the common selective COX-2 inhibitors. Finally, the current work provided a promising approach that can be optimized to serve as a lead project to overcome the cardiovascular toxicity related to the traditional selective COX-2 inhibitors.Due to their unique characteristics, the zebrafish plays a key role in the comprehension of neurobiology of cognition and its pathologies, such as neurodegenerative diseases. More and more molecular tools for this aim are being developed, but our knowledge about the cognitive abilities of zebrafish remains extremely scarce compared to other teleost fish. We aimed to investigate the complex cognitive abilities of zebrafish using a tracking-based automated conditioning chamber that allowed precise experimental control, avoided potential cueing provided by the observer (Clever Hans phenomenon), and was shown to considerably improve learning in other teleosts. A computer presented two visual stimuli in two sectors of the chamber, and zebrafish had to enter the correct sector to obtain a food reward. Zebrafish quickly learned to use the conditioning device and easily performed up to 80 trials per day. In Experiment 1, zebrafish efficiently discriminated between two differently coloured sides, reaching a 75 % accur of zebrafish, which should be taken into account when developing cognitive tasks for this species.Foraging diurnal lizards are well known for their use of visual and chemical cues to detect prey. We already showed that the Balearic lizard is able to detect prey using visual and chemical cues, even from airborne odors. In this study we carried out a field experiment to test if lizards can detect prey using acoustic cues. Our results show that Podarcis lilfordi is able to detect flies trapped inside opaque cups, only using acoustic cues. To our knowledge, this is the first known case of phonotaxis of a diurnal lizard. Thus, P. lilfordi can detect, from far away, current pollinators trapped inside floral chambers of the dead horse arum, Helicodiceros muscivorus. This is another behavioral trait displayed by the Balearic lizard during its complex interaction with the dead horse arum.To solve the low oral bioavailability of curcumin (CUR) due to the limits imposed by gastrointestinal (GI) barrier, we constructed a nano delivery system to evaluate the effect of N-acetyl-L-cysteine (NAC) on intestinal absorption and oral bioavailability of CUR. CUR was first encapsulated in bovine serum albumin nanoparticles (CUR-BSA-NPs), and then was further modified by NAC (CUR-NBSA-NPs). In situ single-pass intestinal perfusion assay demonstrated that CUR-NBSA-NPs displayed excellent permeation and absorption rates in GI tract. Additionally, the distribution study in GI tract revealed that more NBSA-NPs were absorbed by intestinal segments compared to the BSA nanoparticles. Plasma concentration-time curves in rats showed that AUC0-t, Cmax and MRT0-t values of CUR after oral administration of CUR-NBSA-NPs were increased to 3.25-, 4.42-, and 1.43-fold compared with that of CUR suspension. In conclusion, NAC promotes oral absorption of CUR, thereby improving its oral bioavailability.