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ABSTRACT Background Aims Methods Results Conclusion Marionette lines are a feature of the aging face, descending from the oral commissures towards the jaw. VYC‐17.5 L is a dermal filler that contains 17.5 mg/mL of hyaluronic acid (HA) and lidocaine (3 mg/mL); it is intended for the treatment of skin depressions. VYC‐17.5 L has been shown to be safe and effective in different conditions, but there is a lack of published literature on its effectiveness in marionette lines.This 12‐month prospective, open‐label, post‐marketing study evaluated the effectiveness and safety of the injectable HA filler VYC‐17.5 L for the improvement of marionette lines.Adults (≥ 18 years) with mild‐to‐severe marionette lines on the validated Allergan Marionette Line Scale (AMLS) received VYC‐17.5 L on Day 1 with optional touch‐up on Day 14. The primary endpoint was proportion of participants with ≥ 1‐point change in AMLS from baseline at Month 1 (M1). Secondary endpoints were investigator‐ and participant‐rated Global Aesthetic Improvement Scale (GAIS), FACE‐Q satisfaction with facial appearance, and appraisal of lines: marionette. Safety was assessed throughout.A total of 83 participants completed the study; 69.9% of participants had ≥ 1‐point change in AMLS at M1. Investigator and participant GAIS showed improvement. Both FACE‐Q scores significantly improved from baseline (p < 0.0001). A significant volume improvement was seen and maximized at M1. Most participant‐reported injection site reactions were mild or moderate and resolved within 8 days; 14 subjects reported adverse device effects, with the most common being pain, which resolved within 8 days.This prospective, open‐label study showed that VYC‐17.5 L effectively improved marionette lines and was well tolerated. [ABSTRACT FROM AUTHOR]

Background: Macracantorhincosis is a zoonotic disease resulting from inadequate sanitary conditions, which occurs in pigs infected by acanthocephalic helminths called Macracanthorhynchus hirudinaceus. The eggs of these parasites are resistant to cold, high temperatures and can survive up to 3 years in the soil. They are consumed by dung beetles of the Scarabeidae family causing the parasite to evolve into its infective form, the cystacanth. The pig becomes infected after ingestion of either larvae or adult forms of these coleoptera. This work describes a case report of macracantorhincosis found in a pig from the canton of Zaruma located in the province of El Oro, Ecuador. Case: One sow, approximately 24-month-old, weighing 30 kg, presented cachexia, muscle weakness, pale oral and ocular mucosa and a body temperature above 39.4°C. The animal had a bulge on the ventral side of the neck, which evolved causing progressive discomfort to the point that the animal stopped eating. The sow was dewormed for 3 consecutive days. Fifteen days later, the animal had convulsions and muscle tremors, and died some hours after the symptoms started. During necropsy procedure, pale digestive tract membranes and nodules with fibrin were observed in the small intestine (jejunum), which was incised and the presence of parasites adhered to the granulomas detected. Two granulomas for morphological and histological studies and stool samples for coproparasitic test were collected. The collected parasites were fixed in a 10% buffered formalin solution, cross-sections were made and routinely processed for histological studies. The 5 μm thick sections were stained using the hematoxylin and eosin (HE) technique. The parasite’s action involves perforation of the intestinal wall though its proboscis causing peritonitis and enteritis. Other conditions in intestinal dissection such as necrotic areas, inflammation of the submucosa and adult parasites adhered to the intestinal mucosa were also observed. The coproparasitic examination was performed using the flotation and sedimentation techniques. The coproparasitic test detected dark colored feces, semi-solid consistency and the presence of Macracanthorhynchus hirudinaceu eggs. In the histological evaluation of the cross section of the parasite, the presence of circular and longitudinal muscle fibers and lemniscus with their constrictor muscles was observed. Cuticle, hypodermis with tapered fibers and a large number of developing mature eggs were also reported. Discussion: There is no pathognomonic symptomatology about this parasitosis and peritonitis can be generated by intestinal perforations. The findings at necropsy were ulcerations, inflammation in the small intestine and the presence of numerous nodules in the serous layer, where there was penetration of the parasite’s proboscis. When fixed to the mucosa, these parasites cause ulcerations, inflammation and necrosis in the wall of the small intestine. The hypodermic layer is thicker than the muscular layer and the presence of leminis with their constricting muscles are typical features of acanthocephalus. It is considered appropriate to carry out epidemiological studies on the prevalence of the parasite Macracanthorhynchus hirudinaceus at pig farming system in the region, in order to determine the main risk factors. In Ecuador, cases of this disease in humans have not yet been reported, but have already been described in other countries, so the presence of this parasite in family swine farming may be considered a zoonotic-type risk factor. [ABSTRACT FROM AUTHOR]

The killifish Fundulus heteroclitus is an estuarine species with broad physiological plasticity, enabling acclimation to diverse stressors. Previous work suggests that freshwater populations expanded their physiology to accommodate low salinity environments; however, it is unknown whether this compromises their tolerance to high salinity. We used a comparative approach to investigate the mechanisms of a derived freshwater phenotype and the fate of an ancestral euryhaline phenotype after invasion of a freshwater environment. We compared physiological and transcriptomic responses to high- and low-salinity stress in fresh and brackish water populations and found an enhanced plasticity to low salinity in the freshwater population coupled with a reduced ability to acclimate to high salinity. Transcriptomic data identified genes with a conserved common response, a conserved salinity-dependent response and responses associated with population divergence. Conserved common acclimation responses revealed stress responses and alterations in cell-cycle regulation as important mechanisms in the general osmotic response. Salinityspecific responses included the regulation of genes involved in ion transport, intracellular calcium, energetic processes and cellular remodeling. Genes diverged between populations were primarily those showing salinity-specific expression and included those regulating polyamine homeostasis and the cell cycle. Additionally, when populations were matched with their native salinity, expression patterns were consistent with the concept of 'transcriptomic resilience', suggesting local adaptation. These findings provide insight into the fate of a plastic phenotype after a shift in environmental salinity and help to reveal mechanisms allowing for euryhalinity. [ABSTRACT FROM AUTHOR]

Evolutionary solutions to the physiological challenges of life in highly variable habitats can span the continuum from evolution of a cosmopolitan plastic phenotype to the evolution of locally adapted phenotypes. Killifish (Fundulus sp.) have evolved both highly plastic and locally adapted phenotypes within different selective contexts, providing a comparative system in which to explore the genomic underpinnings of physiological plasticity and adaptive variation. Importantly, extensive variation exists among populations and species for tolerance to a variety of stressors, and we exploit this variation in comparative studies to yield insights into the genomic basis of evolved phenotypic variation. Notably, species of Fundulus occupy the continuum of osmotic habitats from freshwater to marine and populations within Fundulus heteroclitus span far greater variation in pollution tolerance than across all species of fish. Here, we explore how transcriptome regulation underpins extreme physiological plasticity on osmotic shock and how genomic and transcriptomic variation is associated with locally evolved pollution tolerance. We show that F. heteroclitus quickly acclimate to extreme osmotic shock by mounting a dramatic rapid transcriptomic response including an early crisis control phase followed by a tissue remodeling phase involving many regulatory pathways. We also show that convergent evolution of locally adapted pollution tolerance involves complex patterns of gene expression and genome sequence variation, which is confounded with body-weight dependence for some genes. Similarly, exploiting the natural phenotypic variation associated with other established and emerging model organisms is likely to greatly accelerate the pace of discovery of the genomic basis of phenotypic variation. [ABSTRACT FROM PUBLISHER]

The full-length cDNA sequence of a putative urea transporter (IfUT) of the facilitated diffusion UT-A type has been cloned from the African lungfish Protopterus annectens. The IfUT cDNA is 1990 bp in length and its open reading frame encodes a 409 amino acid long protein, with a calculated molecular mass of 44,723 Da. The sequence is closest to those of amphibians (∼65% amino acid homology), followed by mammals and elasmobranchs (∼60%), and then teleosts (∼50%). IfUT was clearly expressed in gill, kidney, liver, skeletal muscle and skin. Upon re-immersion in water after 33 days of air exposure ('terrestrialization'), lungfish exhibited a massive rise in urea-N excretion which peaked at 12-30 h with rates of 2000-5000 μmol-N kg-1 h-1 (versus normal aquatic rates of <130 μmol-N kg-1 h-1) and persisted until 70 h. This appears to occur mainly through the skin. Total 'excess' urea-N excretion amounted to ∼81,000-91,000μmol-N kg-1 over 3 days. By real-time PCR, there was no difference in IfUT expression in the ventral abdominal skin between aquatic ammoniotelic controls and terrestrialized lungfish immediately after return to water (0 h), and no elevation of urea-N excretion at this time. However, skin biopsies revealed a significant 2.55-fold elevation of IfUT expression at 14 h, coincident with peak urea-N excretion. At 48 h, there was no longer any significant difference in IfUT mRNA levels from those at 0 and 14 h, or from aquatic fed controls. In accordance with earlier studies, which identified elevated urea-N excretion via the skin of P. dolloi with pharmacology typical of UT-A carriers, these results argue that transcriptional activation of a facilitated diffusion type urea transporter (IfU1) occurs in the skin during re-immersion. This serves to clear the body burden of urea-N accumulated during terrestrialization. [ABSTRACT FROM AUTHOR]

Natural organic matter (NOM) is an important constituent of aquatic environments; however, its influence on aquatic biota remains poorly studied. In the current study, NOM was isolated from nine different sites in southern Ontario, Canada, by the on-site treatment of water by reverse osmosis, followed by cation exchange. NOM from each site was reconstituted to 10 mg of C/L and pH 7.0 and exposed to either adult rainbow trout implanted with indwelling catheters or to in vitro primary cultures of the gill epithelium grown on semipermeable membranes. In both the in vivo and in vitro preparations, NOM was found to hyperpolarize transepithelial potential (TEP), with the magnitude of this change correlating extremely well to the absorptivity of the NOM at 340 nm, which is an index of its aromaticity. Gill hyperpolarization appeared to be independent of Ca2+ complexation by the NOM in all but two samples tested. We argue that NOM has direct actions on the ionic transport and/or permeability properties of fish gills. While NOM effects on the bioavailability of contaminants are well-known, NOM actions on such fundamental physiological properties of the gills have previously been overlooked. These may be of comparable or greater magnitude than commonly reported for other water-quality variables (e.g., hardness, pH, salinity) and therefore of critical importance in ecological understanding and risk assessment. [ABSTRACT FROM AUTHOR]

Abstract: Recent studies have shown that dietary Ca2+ supplementation strongly inhibits uptake of Ca2+ and Cd at the fish gill. To better understand the influence of dietary Ca2+ on branchial Ca2+ transport, we examined the expression of two trout gill calcium transporters during waterborne and dietary Cd exposure, at two different levels of dietary Ca2+. Quantitative polymerase chain reaction (PCR) was used to monitor epithelial calcium channel (ECaC) and sodium–calcium exchange (NCX) mRNA levels following 7–28 days of exposure to these treatments. In brief, juvenile rainbow trout (Oncorhynchus mykiss) were exposed to control, 3μg/L waterborne Cd, 500mg/kg dietary Cd, or a combined 3μg/L waterborne plus 500mg/kg dietary Cd exposure, supplemented with either 20mg/g or 60mg/g dietary calcium (Ca2+). Two-way analysis of variance was used to discern the main effects of Cd exposure and dietary Ca2+ supplementation on ECaC and NCX mRNA levels. We found that dietary Ca2+ supplementation decreased significantly ECaC mRNA expression on days 14 and 21. In comparison, NCX mRNA levels were not influenced by dietary Ca2+ supplementation, but rather were significantly inhibited in the combined waterborne and dietary Cd exposure on day 7 alone. Statistical analysis found no interactive effects between Cd exposure and dietary Ca2+ exposure at any time point, except for day 28.This study provides evidence of the importance of nutritional status on the transcriptional regulation of ion transport at the fish gill. We discuss the importance of diet and nutritional status to the development of new regulatory approaches, such as the biotic ligand model, which currently do not account for the significance of diet on metal bioavailability in aquatic organisms. [Copyright &y& Elsevier]

Na+ and Ca2+ regulation were compared in two euryhaline species, killifish (normally estuarine-resident) and rainbow trout (normally freshwater-resident) during an incremental salinity increase. Whole-body unidirectional fluxes of Na+ and Ca2+, whole body Na+ and Ca2+, and plasma concentrations (trout only), were measured over 1-h periods throughout a total 6-h protocol of increasing salinity meant to simulate a natural tidal flow. Killifish exhibited significant increases in both Na+ influx and efflux rates, with efflux slightly lagging behind efflux up to 60% SW, but net Na+ balance was restored by the time killifish reached 100% SW. Whole body Na+ did not change, in agreement with the capacity of this species to tolerate daily salinity fluctuations in its natural habitat. In contrast, rainbow trout experienced a dramatic increase in Na+ influx (50-fold relative to FW values), but not Na+ efflux between 40 and 60% SW, resulting in a large net loading of Na+ at higher salinities (60–100% SW), and increases in plasma Na+ and whole body Na+ at 100% SW. Killifish were in negative Ca2+ balance at all salinities, whereas trout were in positive Ca2+ balance throughout. Ca2+ influx rate increased two- to threefold in killifish at 80 and 100% SW, but there were no concomitant changes in Ca2+ efflux. Ca2+ flux rates were affected to a larger degree in trout, with twofold increases in Ca2+ influx at 40% SW and sevenfold increases at 100% SW. Again, there was no change in Ca2+ efflux with salinity, so plasma Ca2+ concentration increased in 100% SW. As the killifish is regularly submitted to increased salinity in its natural environment, it is able to rapidly activate changes in unidirectional fluxes in order to ensure ionic homeostasis, in contrast to the trout. [ABSTRACT FROM AUTHOR]

A novel cell isolation technique was used to characterize cadmium and calcium uptake in distinct populations of gill cells from the adult rainbow trout (Oncorhynchus mykiss). A specific population of mitochondria-rich (MR) cell, termed the PNA+ MR cell (PNA is peanut lectin agglutinin), was found to accumulate over threefold more 109Cd than did PNA- MR cells, pavement cells (PV cells), and mucous cells during a 1-h in vivo exposure at 2.4 μg/l 109Cd. In vitro 109Cd exposures, performed in standard PBS and Cl--free PBS, at concentrations from 1 to 16 μg/l 109Cd, were also carried out to further characterize Cd2+ uptake kinetics. As observed during in vivo experiments, PNA+ MR cells accumulated significantly more 109Cd than did other cell types when exposures were performed by an in vitro procedure in PBS. Under such conditions, Cd2+ accumulation kinetics in all cell types could be described with Michaelis-Menten relationships, with Km values of ∼3.0 μg/l Cd (27 nM) for both MR cell subtypes and 8.6 μg/l Cd (77 nM) for PV cells. In similar experiments performed in Cl--free conditions, a significant reduction in 109Cd accumulation in PNA+ MR cells was seen but not in PNA- MR or in PV cells. In vitro 45Ca fluxes were also performed to determine the cellular localization of Ca2+ transport in these functionally distinct populations of gill cells. 45Ca uptake was most pronounced in PNA+ MR cells, with levels over threefold higher than those found in either PNA- MR or in PV cells. Results from the present study suggest that the PNA+ MR cell type is a high-affinity and high-capacity site for apical entry of Cd2+ and Ca2+ in the gill epithelium of rainbow trout. [ABSTRACT FROM AUTHOR]

Mitochondria-rich cells (MR cells) of the gills of rainbow trout undergo changes in relative distribution and biochemical function during acclimation to partialstrength (10‰) and full-strength (30‰) seawater. In isolated total gill cells, Na+/K+-ATPase activity increased fivefoid and H+-ATPase activity decreased fourfold when trout were acclimated to either 10&permi;; or 30‰ seawater. When total MR gill cells were separated based on differential binding to peanut lectin agglutinin (PNA), the PNA subtypes underwent a change in relative distribution in seawater-acclimated fish. In freshwater, the ratio of PNA-:PNA+ was 65:35 while in seawater the distribution changed to 20:80 PNA-:PNA+. Additionally, differential changes in Na+/K+-ATPase and H+-ATPase activity in each of the independent cell types occurred during seawater acclimation; Na+/K+-ATPase activity in the PNA- cells increased by 197% while in PNA+ cells Na+/K+ATPase decreased by 57%. However, H+-ATPase activity was decreased in both PNA- (84%) and PNA+ (72%) subtypes during acclimation to seawater. [ABSTRACT FROM AUTHOR]

Toxicogenomics attempts to define how the regulation and expression of genes mediate the toxicological effects associated with exposure to a chemical. DNA microarrays are rapidly becoming one of the tools of choice for large-scale toxicogenomic studies. An approach in modern toxicogenomics has been to classify toxicity based on gene transcriptional patterns; comparing the transcriptional responses of a chemical with unknown toxicity to those for which the transcriptional profiles and toxicological endpoints have been well characterized. Recent evidence suggests that gene expression microarrays may be instrumental in defining mechanisms of action of toxicants. However, several assumptions are inherent to a toxicogenomic-based approach in toxicology, many of which remain to be validated. Gene expression profiling using DNA microarrays represents a snapshot of the gene transcriptional responses occurring at a particular time and within a particular tissue. Toxicity, on the other hand, represents a continuum of possible effects governed by both temporal and spatial factors that are inextricably contingent upon the exposure conditions. The perceived toxicological properties of any chemical are dependent on the route, dose, and duration of the exposure, and as such, gene expression patterns are also subject to these variables. Correct interpretation of DNA microarray data for the assessment of the toxicological properties of chemicals will require that temporal and spatial gene expression profiles be accounted for. These considerations are further compounded in ecotoxicological studies, during which altered gene expression patterns induced from exposure to an anthropogenic substance must be discernible over and above the complex effects that phenotypic, genotypic, and environmental variables have on gene expression. To this end, the greatest utility of DNA microarrays in the field of ecotoxicology may be in predicting the toxicological modes of action of anthropogenic substances on host physiology, particularly in non-model organisms. Predictable and accurate assessment of the impacts of a chemical substance in ecotoxicology will require that classical toxicological endpoints be used to validate any effects predicted based on gene expression profiling. Validated expression profiling may subsequently find utility in ecotoxicological-based computer simulation models, such as the Biotic Ligand Model (BLM), in which gene expression information may be integrated with geochemical, pharmacokinetic, and physiological data to accurately assess and predict toxicity of metals to aquatic organisms. [Copyright &y& Elsevier]

Potassium channel activity is important for modulating mammalian macrophage antimicrobial functions. The involvement of potassium channels in mediation of immune cell function in lower vertebrates, such as teleost, has not been explored. Since relatively little is known about the types of potassium channels present in fish macrophages, pharmacological blockers with broad ranges of activity were tested: 4-aminopyridine (4-AP), quinine, and tetraethylammonium chloride (TEA). The potassium channel blockers inhibited reactive nitrogen intermediates (RNI) and reactive oxygen intermediates (ROI) production by goldfish macrophages activated with bacterial lipopolysaccharide (LPS) and/or macrophage activating factor (MAF)-containing supernatants. Quinine was the most potent inhibitor with an IC50 of 50 μM, while the other blockers, 4-AP and TEA, had IC50 of 1.2 and 0.6 mM, respectively. A reversible depolarization of the goldfish macrophage plasma membrane potential (Vm) was observed following treatments with potassium channel blockers, and was related to transcriptional changes in the inducible nitric oxide synthase gene (iNOS). Down-regulation of antimicrobial activities and depolarization of the goldfish macrophage plasma membrane were not a consequence of reduced cell number or viability, suggesting that potassium channels are required for generation of appropriate goldfish macrophage antimicrobial functions. [Copyright &y& Elsevier]

Presents a study that developed a magnetic cell separation (MACS) technique for isolating and characterizing peanut lectin agglutin positive cells from rainbow trout gills. Experimental procedure; Gill digestion protocol; Isolation of mitochondria-rich (MR) chloride and MR pavement cells by MACS.

Juvenile rainbow trout (Oncorhynchus mykiss) were subjected to a 2-day radioactive pulse of 110mAg at 11.9 μg/l (as AgNO3), followed by a 19-day post-tracer exposure to non-radioactive Ag(I) (3.8 μg/l). The distribution of 110mAg in the gills, liver, intestine, kidney, brain and remaining carcass was investigated over a 19-day post-tracer period. Initially, the intestine contained the highest proportion of the 110mAg burden (34%), however, by day 8, less than 5% of the total radioactivity remained in this tissue. The majority of the 110mAg eliminated from the intestine appeared to distribute to the liver. Eventually, the 110mAg content in the liver accounted for as much as 65% of the total radioactivity in the fish. Apart from the liver and intestine, only the gills and carcass contained any appreciable amount (>5%) of the total body 110mAg content. Liver and gill samples were fractionated using differential centrifugation techniques to discern the subcellular distribution of 110mAg in these tissues. In the liver, the 110mAg levels in the cytosolic fraction increased from 35% to 72% of the total cellular burden between days 8 and 19, respectively. The radioactive pulse in the gills was predominantly found in a membrane compartment termed the nuclear fraction (∼60% of the total). Little change was observed over time (day 8 to day 19) to the subcellular distribution of Ag in the gills. Using size-exclusion chromatography, most (∼70%) of the 110mAg content in the liver cytosol eluted at a molecular weight characteristic of metallothionein. The cytosolic distribution of 110mAg in gills was quite diffuse, occurring primarily in the heavy molecular weight fractions. [Copyright &y& Elsevier]

Despite the youthfulness of hybrid halide perovskite solar cells, their efficiencies are currently comparable to commercial silicon and have surpassed quantum‐dots solar cells. Yet, the scalability of these devices is a challenge due to their low reproducibility and stability under environmental conditions. However, the techniques reported to date to tackle such issues recurrently involve the use of solvent methods that would further complicate their transfer to industry. Herein a reliable alternative relaying in the implementation of an ultrathin plasma polymer as a passivation interface between the electron transport layer and the hybrid perovskite layer is presented. Such a nanoengineered interface provides solar devices with increased long‐term stability under ambient conditions. Thus, without involving any additional encapsulation step, the cells retain more than 80% of their efficiency after being exposed to the ambient atmosphere for more than 1000 h. Moreover, this plasma polymer passivation strategy significantly improves the coverage of the mesoporous scaffold by the perovskite layer, providing the solar cells with enhanced performance, with a champion efficiency of 19.2%, a remarkable value for Li‐free standard mesoporous n‐i‐p architectures, as well as significantly improved reproducibility. [ABSTRACT FROM AUTHOR]

Nanopatterned ferromagnetic (FM) thin films have specific characteristics that make them a workhorse for sensors based on magnonic, magnetoplasmonic, or anisotropic magneto-resistive effects. Undulated FM thin films have been studied because of their tunable uniaxial anisotropy. They have been traditionally understood by means of Schlömann's model taking account of shape-induced magnetic anisotropies in softly corrugated systems. Here, we show how it cannot describe accurately the magnetic behavior of highly corrugated FM systems within a thickness region of less than the ripple amplitude. We report on the magnetization reversal processes detected in Permalloy films deposited onto highly corrugated patterns (250 nm in periodicity, 180 nm in amplitude) in a wide thickness range (15–150 nm), finding both that the anisotropy of the system does not correspond to a uniaxial type for FM thicknesses larger than 40 nm and that the anisotropy of the system increases with the FM thickness. Based on the results, we hypothesize that whereas Schlömann's model is valid for softly corrugated thin films, it fails to explain magnetization reversal processes of highly corrugated thin films, especially when the ripple amplitude is much greater than the deposited FM layer thickness. By means of micromagnetic simulations, we find an increment of anisotropy with thickness, just as in the experimental, as well as determine the arise of magnetic domains at the ridges of high thickness corrugated FM thin films. This approach will help to get a better understanding of operating mechanisms in magnetic field sensors based on undulated ferromagnetic materials. [ABSTRACT FROM AUTHOR]

Following the Deepwater Horizon oil spill, approximately 7 million liters of the dispersant Corexit 9500A were released to promote oil biodegradation by breaking up surface oil slick formation. This process is accomplished via amphipathic anionic surfactants within dispersants that facilitate the mixing of aqueous and lipid phases. However, the amphipathicity of Corexit may also cause it to interact with biological membranes like the gill, impairing gill function and ultimately disrupting physiological processes mediated by it, such as osmoregulation. The goal of this study was to investigate the osmoregulatory effects and toxicity of Corexit in Gulf killifish. Killifish at the embryonic, larval, juvenile, and adult life stages were exposed to Corexit in water of different salinities to assess the interactive effects of ontogeny and salinity on Corexit toxicity. Corexit was not toxic to embryos except when exposed in hyperosmotic water where it had negligible effects; however, its toxicity to killifish increased dramatically following hatch, showing its greatest deleterious effects in adults. Corexit tended to increase sodium and chloride burdens in killifish when exposed in hyperosmotic waters and reduced whole-body and plasma ion concentrations in fish exposed to hypoosmotic waters. However, Corexit exposure at hyperosmotic salinities resulted in an increased differential accumulation of sodium over chloride as killifish matured. These findings suggest that Corexit may impair gill structure or alter specific components of osmoregulatory function, thus impacting osmoregulation in hypersosmotic and hypoosmotic waters, potentially impairing survival during osmotic challenges. Furthermore, the magnitude of these impacts continues to increase concomitant with gill ontogeny. • Sensitivity to Corexit increases as Gulf killifish mature from embryos to adults. • Corexit was more toxic to Gulf killifish in hyperosmotic waters relative to hypoosmotic waters at all life stages. • The effect of Corexit on osmoregulatory physiology of killifish appears to change with maturation. [ABSTRACT FROM AUTHOR]

Syntheses of research spanning diverse taxa, ecosystems, timescales, and hierarchies are crucial for understanding the cumulative impacts of the Macondo oil spill in the Gulf of Mexico. Four years after the spill, responses of estuarine fishes to oil pollution have been studied at organismal through population levels, and there is an emerging mismatch between consistent negative impacts detected among individual organisms and absence of measurable negative impacts among populations. To reconcile this apparent contradiction, we draw on lessons learned from this and previous spills to consider two classes of mechanisms: factors obscuring negative population impacts despite known organismal responses (e.g., high spatiotemporal variability, offsetting food-web cascades, fishery closures, temporal lags) and factors dampening population-level costs despite known organismal responses (e.g., behavioral avoidance, multiple compensatory pathways). Thus, we highlight critical knowledge gaps that should form the basis of current and future oil-spill research priorities to assess ecosystem responses to basin-scale disturbance. [ABSTRACT FROM PUBLISHER]

In this report, a method is proposed for determining the fluctuations of physical and structural properties in metallic ferromagnetic samples by magnetic scanning. The method is based on the shielding of a circular loop electromagnetic field source using a ferromagnetic and metallic sheet. The shielding of the electromagnetic field depends on the field frequency and amplitude as well as the electrical conductivity and magnetic permeability of the sheet. The proposed method does not require winding around the sheet. The experimental AC shielding results are reported. [ABSTRACT FROM AUTHOR]

The larvae of unionid freshwater mussels (i.e., glochidia) undergo a parasitic stage requiring their attachment to the external epithelia of fish hosts, where they metamorphose into free-living juveniles. We describe the physiological effects in bluegill sunfish (Lepomis macrochirus) of infection with glochidia from the paper pondsbell (Utterbackia imbecillis). Glocbidia accumulation on bluegill increased dramatically at concentrations of 2000 glochidia liter-1 and above, reacbing a maximum attachment density of about 30 glochidia g-1 fish at 4000 glochidia liter-1. Plasma cortisol was the most sensitive indicator of biological effect to glochidial exposure, increasing significantly in hosts exposed to 2000 glochidia liter-1 or greater. Glochidia were 31% more likely to undergo successful juvenile metamorphosis when attached to bluegill with elevated plasma cortisol, largely due to the enhanced survivorship of these larvae during the first 48 h after infection. We tested the hypothesis that glochidial attachment and juvenile metamorphosis were stimulated directly by plasma cortisol in fish hosts. Bluegill were given an intraperitoneal injection of cortisol, then infected with 1000 glochidia liter-1 at 48 h after hormone supplementation. Cortisol-injected fish had a 42% increase in the number of attached glochidia g-1 fish and a 28% increase in larval metamorphosis compared to sham-injected and control fish. We provide evidence that cortisol enhances glochidial metamorphosis on hosts by improving the retention of attached glochidia. This study gives insights into the influence host physiology on glochidial attachment and juvenile mussel transformation. [ABSTRACT FROM AUTHOR]

Abstract: We have studied intracellular pH (pHi) recovery in isolated trout gill mitochondrion-rich (MR) cells following acidification by the NH4Cl pre-pulse technique. Within a mixed MR cell population, one cell type displayed Na+-independent pHi recovery while the other cell type lacked a Na+-independent pHi recovery. Cells displaying Na+ independent recovery exhibited a significantly higher buffering capacity compared to cells lacking Na+-independent pHi recovery. Cells displaying Na+ independent recovery were identified as PNA+ (peanut lectin agluttinin binding) MR cells while those unable to recover were identified as PNA− (non-peanut lectin agluttinin binding) MR cells. Therefore, recovery from acidification in the absence of Na+ provides a direct functional marker for PNA+ and PNA− MR cells. Re-addition of Na+ to acidified cells resulted in a transient pHi recovery in both cell types. This event was abolished by amiloride (500µM) but it was insensitive to phenamil (50µM). The phorbol ester PMA (1µM) potentiated the Na+ induced pHi recovery suggesting that activation by PKC is required for continuous Na+/H+ exchanger activity in trout gill MR cells. This study is the first functional description of pHi recovery in lectin-identified trout gill MR cells and provides insight into a putative cellular signaling mechanism that may control pHi regulation in the gill epithelium. [Copyright &y& Elsevier]

Abstract: The zebrafish model system is ideal for studying nervous system development. Ultimately, one would like to link the developmental biology to various aspects of behavior. We are studying the consequences of nicotine exposure on nervous system development in zebrafish and have previously shown that chronic nicotine exposure produces paralysis. We also have made observations that the embryos moved in the initial minutes of the exposure as the bend rates of the musculature increased. This nicotine induced behavior manifests as an increase in the rate of spinal musculature bends, which spontaneously begin at ∼18 h post fertilization. The behavioral observations prompted the systematic characterization of nicotine-induced modulation of zebrafish embryonic motor output; bends of the trunk musculature. We first characterized embryonic motor output in zebrafish embryos with and without their chorions. We then characterized the motor output in embryos raised at 28 °C and 25 °C. The act of dechorionation along with temperature influenced the embryonic bend rate. We show that nicotine exposure increases embryonic motor output. Nicotine exposure caused the musculature bends to alternate in a left–right–left fashion. Nicotine was able to produce this phenotype in embryos lacking supraspinal input. We then characterize the kinetics of nicotine influx and efflux and demonstrate that nicotine as low as 1 μM can disrupt embryonic physiology. Taken together, these results indicate the presence of nicotinic acetylcholine receptors (nAChRs) associated with embryonic spinal motor circuits early in embryogenesis. [Copyright &y& Elsevier]

Although urea production and metabolism in lungfish have been thoroughly studied, we have little knowledge of how internal osmotic and electrolyte balance are controlled during estivation or in water. We tested the hypothesis that, compared with the body surface of teleosts, the slender African lungfish (Protopterus dolloi) body surface was relatively impermeable to water, Na+, and Cl- due to its greatly reduced gills. Accordingly, we measured the tritiated water (3H-H2O) flux in P. dolloi in water and during air exposure. In water, 3H-H2O efflux was comparable with the lowest measurements reported in freshwater teleosts, with a rate constant (K) of 17.6% body water h-1. Unidirectional ion fluxes, measured using 22Na+ and 36Cl- indicated that Na+ and Cl- influx was more than 90% lower than values reported in most freshwater teleosts. During air exposure, a cocoon formed within 1 wk that completely covered the dorsolateral body surface. However, there were no disturbances to blood osmotic or ion (Na+, Cl-) balance, despite seven- to eightfold increases in plasma urea after 20 wk. Up to 13-fold increases in muscle urea (on a dry-weight basis) were the likely explanation for the 56% increase in muscle water content observed after 20 wk of air exposure. The possibility that muscle acted as a "water reservoir" during air exposure was supported by the 20% decline in body mass observed during subsequent reimmersion in water. This decline in body mass was equivalent to 28 mL water in a 100-g animal and was very close to the calculated net water gain (approximately 32 mL) observed during the 20-wk period of air exposure. Tritiated water and unidirectional ion fluxes on air-exposed lungfish revealed that the majority of water and ion exchange was via the ventral body surface at rates that were initially similar to aquatic rates. The 3H-H2O flux declined over time but increased upon reimmersion. We conclude that the slender lungfish body surface, including the gills, has relatively low permeability to water and ions but that the ventral surface is an important site of osmoregulation and ionoregulation.We further propose that an amphibian-like combination of ventral skin water and ion permeability, plus internal urea accumulation during air exposure, allows P. dolloi to extract water from its surroundings and to store water in the muscle when the water supply becomes limited. [ABSTRACT FROM AUTHOR]

In the present study, we compare changes in host cell plasma membrane potential (Vm), K+ fluxes, and NO production during K+ channel blockade with those changes that occur during infection with Leishmania major. Infection of P388D.1 cells with L. major promastigotes or treatment with K+ channel blockers (either 1 mM 4-AP, 10 mM TEA, or 200 μM quinine) suppressed NO production. Inhibition of NO production correlated with depolarization of the P388D.1 cell Vm. Infection of P388D.1 cells with L. major increased the unidirectional influx of rubidium (86Rb), a tracer for K+ flux, that was comparable to that induced by K+ channel blockade by 1 mM 4-AP. The similar effects of K+ channel blockers and L. major on NO production, K+ influx, and Vm suggest that K+ channel activity and the maintenance of Vm is important for NO production in these cells. We suggest that intracellular parasites employ a strategy to inhibit NO production by disrupting Vm during the invasion/infection process by altering host cell K+ channel activity. [Copyright &y& Elsevier]

The Fundulus genus of killifish includes species that inhabit marshes along the U.S. Atlantic coast and the Gulf of Mexico, but differ in their ability to adjust rapidly to fluctuations in salinity. Previous work suggests that euryhaline killifish stimulate polyamine biosynthesis and accumulate putrescine in the gills during acute hypoosmotic challenge. Despite evidence that polyamines have an osmoregulatory role in euryhaline killifish species, their function in marine species is unknown. Furthermore, the consequences of hypoosmotic-induced changes in polyamine synthesis on downstream pathways, such as ƴ-aminobutyric acid (Gaba) production, have yet to be explored. Here, we examined the effects of acute hypoosmotic exposure on polyamine, glutamate, and Gaba levels in the gills of a marine (F. majalis) and two euryhaline killifish species (F. heteroclitus and F. grandis). Fish acclimated to 32 ppt or 12 ppt water were transferred to fresh water, and concentrations of glutamate (Glu), Gaba, and the polyamines putrescine (Put), spermidine (Spd), and spermine (Spm) were measured in the gills using high-performance liquid chromatography. F. heteroclitus and F. grandis exhibited an increase in gill Put concentration, but showed no change in Glu or Gaba levels following freshwater transfer. F. heteroclitus also accumulated Spd in the gills, whereas F. grandis showed transient increases in Spd and Spm levels. In contrast, gill Put, Spm, Glu, and Gaba levels decreased in F. majalis following freshwater transfer. Together, these findings suggest that increasing polyamine levels and maintaining Glu and Gaba levels in the gills may enable euryhaline teleosts to acclimate to shifts in environmental salinity. [Display omitted] • We measured gill polyamine and Gaba levels in killifish during freshwater exposure. • Euryhaline species (F. heteroclitus and F. grandis) had elevated levels of putrescine (Put) following freshwater transfer. • F. heteroclitus and F. grandis showed no change in glutamate (Glu) or Gaba levels. • Marine species (F. majalis) decreased Put, spermine, Glu, and Gaba levels. • Elevated gill polyamine synthesis may be indicative of osmotic plasticity in fishes. [ABSTRACT FROM AUTHOR]

The effect of the addition of different protein sources on the sensory properties of meat products was evaluated. Pork liver pâté, turkey patties, cooked turkey breast, fresh pork sausages, and marinated turkey breast were elaborated with soybean (control), and other protein sources, such as aspea, lentil, bean, Chlorella, Spirulina, and dairy protein. Physicochemical parameters (pH, color, and hardness), taste profile, acceptance, and preference were assessed. The incorporation of different protein sources in meat products modified the sensorial characteristics, which differentially influenced the acceptance of panelists, generating panelist groups with different preference profiles. Meat products elaborated with Chlorella and Spirulina protein presented a good acceptance in pork liver pâté. Our data showed greater acceptability for the meat products supplemented with bean and lentil protein. Therefore, bean and lentil protein could be considered as suitable alternatives for the replacement of soy protein in meat products. Practical applications: A new food product can be designed by improving or modifying meat products and they will have the characteristics that suit customer's needs. Enrichment of meat products with protein leads to further enhancement in nutritional profile and market opportunity but their sensory profile could modify their sensorial attributes. Therefore, the impact of these changes should be studied in order to predict the consumer acceptance of the new developed products. [ABSTRACT FROM AUTHOR]

Currently, many meat products are made with soy protein in order to improve their nutritional profile. This is an inconvenience for people allergic to soy, and therefore it is necessary to look for alternatives to this protein to improve their quality of life. In this study, changes in the physicochemical and nutritional properties of cooked turkey breast containing various sources of alternative proteins to soy proteins (pea, broad bean, lentil, Spirulina and Chlorella) were evaluated. Samples formulated with algae showed significant (p < 0.05) changes on physical parameters and chemical composition of cooked turkey breast. Color parameters were also affected by protein source, showing the highest L* values in samples prepared with Chlorella and Spirulina protein (56.13). On the other hand, a* values were lower in cooked turkey breasts containing algal proteins (−2.34 Chlorella and −1.08 Spirulina) compared to control (1.66). Regarding textural parameters, the cooked turkey breast samples prepared with Chlorella protein showed the lowest hardness values (16.89 N) compared to those elaborated with soy protein (36.95 N). The replacement of soy protein by the other algae and vegetable protein sources did not change the adhesiveness values, ranging between 0.56 and 0.75 N·s, for samples manufactured with Chlorella and soy protein, respectively. Amino acids profile was improved when complemented with Spirulina protein, presenting the highest levels of essential amino acids (6.20 g/100 g). In addition, the ratio between essential and non‐essential amino acids increased (from 0.96 to 1.03 for broad bean and Chlorella, respectively). Hence, this study demonstrates that the inclusion of algae proteins can be considered as an alternative to soy proteins for cooked turkey breast formulations and can be a novel source of proteins for people allergic to soy proteins. Practical applications: This study demonstrates that the inclusion of algae proteins can be considered as an alternative to soy proteins for cooked turkey breast formulations and can be a novel source of proteins for people allergic to soy proteins. [ABSTRACT FROM AUTHOR]

Genomic and physiological responses in Gulf killifish (Fundulus grandis) in the northern Gulf of Mexico have confirmed oil exposure of resident marsh fish following the Macondo blowout in 2010. Using these same fish, we evaluated otolith microchemistry as a method for assessing oil exposure history. Laser-ablation inductively-coupled-plasma mass spectrometry was used to analyze the chemical composition of sagittal otoliths to assess whether a trace metal signature could be detected in the otoliths of F. grandis collected from a Macondo-oil impacted site in 2010, post-spill relative to pre-spill, as well as versus fish from areas not impacted by the spill. We found no evidence of increased concentrations of two elements associated with oil contamination (nickel and vanadium) in F. grandis otoliths regardless of Macondo oil exposure history. One potential explanation for this is that Macondo oil is relatively depleted of those metals compared to other crude oils globally. During and after the spill, however, elevated levels of barium, lead, and to a lesser degree, copper were detected in killifish otoliths at the oil-impacted collection site in coastal Louisiana. This may reflect oil contact or other environmental perturbations that occurred concomitant with oiling. For example, increases in barium in otoliths from oil-exposed fish followed (temporally) freshwater diversions in Louisiana in 2010. This implicates (but does not conclusively demonstrate) freshwater diversions from the Mississippi River (with previously recorded higher concentrations of lead and copper), designed to halt the ingress of oil, as a mechanism for elevated elemental uptake in otoliths of Louisiana marsh fishes. These results highlight the potentially complex and indirect effects of the Macondo oil spill and human responses to it on Gulf of Mexico ecosystems, and emphasize the need to consider the multiple stressors acting simultaneously on inshore fish communities. [ABSTRACT FROM AUTHOR]

Polyamines are a family of low molecular weight organic cations produced in part by the coordinated actions of arginase II (Arg II) and ornithine decarboxylase (Odc). Although gill polyamine homeostasis is affected by acute transfer to fresh water, little is known of its function in fish osmoregulation. The current study investigated the role of polyamines in the compensatory response of hypoosmotic challenge in the euryhaline fish, Fundulus grandis . Adult F. grandis were acclimated to 5 ppt water, transferred abruptly to 5, 2, 1, 0.5 and 0.1 ppt water, and assessed for osmoregulatory function, gill morphology, and polyamine homeostasis. The plasma osmolality, Na + concentration, and Cl − concentration were only significantly reduced during exposure to salinities at or below 0.5 ppt, although these effects were transient except in the 0.1 ppt treatment. The phenotype of mitochondrion-rich cells (MRCs) shifted from a seawater-type to a freshwater-type only at salinities that also produced a plasma osmotic disturbance. Hypoosmotic exposure increased the concentrations of putrescine, spermidine, and spermine in the gill over the entire 7 day period. Exposure to 0.1 ppt water also transiently increased gill caspase-3 activity and gill mRNA levels of the immediate-early response genes, c-fos and c-myc , thus tightly associating polyamines with gill remodeling during freshwater acclimation. Furthermore, arginase II and ornithine decarboxylase mRNA levels were most highly expressed in MRCs, and these levels were further increased only in the 0.1 ppt treatment. Reduction of gill polyamine levels following administration of the Odc inhibitor, alpha- dl -difluoromethylornithine (DFMO), inhibited gill caspase-3 activity, but surprisingly reduced the magnitude of the plasma osmotic imbalance elicited by exposure to 0.1 ppt water. We used isolated opercular epithelia mounted on Ussing chambers to assess the influence of polyamines on the attenuating response of hypotonic shock on active Cl − secretion. Spermidine partially reduced the decrease of short-circuit current ( I sc ) and membrane conductance ( G t ) produced by hypotonic exposure. These data suggest polyamines blunt the hypotonic inhibition of NaCl secretion and may lead to early apoptosis of seawater ionocytes and their replacement by FW-type ionocytes. [ABSTRACT FROM AUTHOR]

• Swimming fitness and two-dimensional landmark-based geometric morphometrics with multivariate generalized linear modeling were used to identify the transgenerational effects of crude oil exposure in adult gulf killifish. • Statistical models demonstrate that paternal (F0) oiling rather than maternal (F0) oiling explains more of the variance in fish shape, including effects such as reduced body length and altered body depth and aberrant spinal curvature and altered angles of head projection relative to the body axis. • Anatomical effects persisted in progeny for at least two generations despite progeny being raised continuously in clean water. • The aerobic swimming performance of progeny derived from oiled fathers was also impaired for at least two generations. The current study involved exposing adult F0 Gulf killifish (Fundulus grandis) to Macondo-252 oil for 36 to 44 days and assessing the effects of this oiling on the swimming performance and morphology in two generations of progeny reared in clean water. Following exposure to oil, the F0 fish were used as broodstock to generate four lineages of F1 fish using a full-matrix mating design derived from the gametes of clean and oil-exposed parents. Later, the four lineages of F1 fish were used as broodstock to create an F2 generation of the same four lineages. We found few differences in embryonic outcome (% dead,% hatched, and% unhatched) in any of the four lineages of F1 and F2 fish. However, as adults, F1 and F2 fish derived from oil-exposed males from the F0 generation had significantly lower critical swimming speeds (U crit) than both the control and maternally oil-exposed lineages. Additionally, progeny of oil-exposed fish had altered body shape based on the statistical analysis of two-dimensional landmark-based geometric morphometrics. Fish from oil-exposed lineages showed increased body depth, altered spinal curvature, and changes in the upward angle of projection of the head. Both generations had a significant main effect of maternal and paternal oil exposure on shape; however, F0 paternal oil exposure explained more of the variance in shape across both generations relative to F0 maternal exposure. Our findings demonstrate that parental exposure to oil can impact the shape and aerobic swimming capacity of offspring for at least two generations after the original paternal oiling. [ABSTRACT FROM AUTHOR]

Germ cell tumors (GCTs) comprise 95% of malignant tumors arising in the testes. The present study reports a patient diagnosed with non-seminomatous testicular cancer, stage IB, with a good risk prediction according to the International Germ Cell Cancer Collaborative Group classification. The patient received chemotherapy with bleomycin, etoposide and cisplatin, and achieved complete remission. Eleven years later, while receiving treatment with interferon β-1a for multiple sclerosis, the patient developed a relapse of the original cancer in the lungs and lymph nodes. The majority of GCTs relapse within the first two years of treatment, while 2-4% of patients can present with late relapses. There is no clear established association between multiple sclerosis and testicular cancer; we present the hypothesis that the inmunosupressor treatment that was administered for the multiple sclerosis promoted the cancer relapse. [ABSTRACT FROM AUTHOR]

Environmental salinity presents a key barrier to dispersal for most aquatic organisms, and adaptation to alternate osmotic environments likely enables species diversification. Little is known of the functional basis for derived tolerance to environmental salinity. We integrate comparative physiology and functional genomics to explore the mechanistic underpinnings of evolved variation in osmotic plasticity within and among two species of killifish; Fundulus majalis harbours the ancestral mainly salt-tolerant phenotype, whereas Fundulus heteroclitus harbours a derived physiology that retains extreme salt tolerance but with expanded osmotic plasticity towards the freshwater end of the osmotic continuum. Common-garden comparative hypo-osmotic challenge experiments show that F. heteroclitus is capable of remodelling gill epithelia more quickly and at more extreme osmotic challenge than F. majalis. We detect an unusual pattern of baseline transcriptome divergence, where neutral evolutionary processes appear to govern expression divergence within species, but patterns of divergence for these genes between species do not follow neutral expectations. During acclimation, genome expression profiling identifies mechanisms of acclimation-associated response that are conserved within the genus including regulation of paracellular permeability. In contrast, several responses vary among species including those putatively associated with cell volume regulation, and these same mechanisms are targets for adaptive physiological divergence along osmotic gradients within F. heteroclitus. As such, the genomic and physiological mechanisms that are associated with adaptive fine-tuning within species also contribute to macro-evolutionary divergence as species diversify across osmotic niches. [ABSTRACT FROM AUTHOR]

The Deepwater Horizon oil rig disaster resulted in crude oil contamination along the Gulf coast in sensitive estuaries. Toxicity from exposure to crude oil can affect populations of fish that live or breed in oiled habitats as seen following the Exxon Valdez oil spill. In an ongoing study of the effects of Deepwater Horizon crude oil on fish, Gulf killifish (Fundulus grandis) were collected from an oiled site (Grande Terre, LA) and two reference locations (coastal MS and AL) and monitored for measures of exposure to crude oil. Killifish collected from Grande Terre had divergent gene expression in the liver and gill tissue coincident with the arrival of contaminating oil and up-regulation of cytochrome P4501A (CYP1A) protein in gill, liver, intestine, and head kidney for over one year following peak landfall of oil (August 2011) compared to fish collected from reference sites. Furthermore, laboratory exposures of Gulf killifish embryos to field-collected sediments from Grande Terre and Barataria Bay, LA, also resulted in increased CYP1A and developmental abnormalities when exposed to sediments collected from oiled sites compared to exposure to sediments collected from a reference site. These data are predictive of population-level impacts in fish exposed to sediments from oiled locations along the Gulf of Mexico coast. [ABSTRACT FROM AUTHOR]

The biological consequences of the Deepwater Horizon oil spill are unknown, especially for resident organisms. Here, we report results from a field study tracking the effects of contaminating oil across space and time in resident killifish during the first 4 mo of the spill event. Remote sensing and analytical chemistry identified exposures, which were linked to effects in fish characterized by genome expression and associated gill immunohistochemistry, despite very low concentrations of hydrocarbons remaining in water and tissues. Divergence in genome expression coincides with contaminating oil and is consistent with genome responses that are predictive of exposure to hydrocarbon-like chemicals and indicative of physiological and reproductive impairment. Oil-contaminated waters are also associated with aberrant protein expression in gill tissues of larval and adult fish. These data suggest that heavily weathered crude oil from the spill imparts significant biological impacts in sensitive Louisiana marshes, some of which remain for over 2 mo following initial exposures. [ABSTRACT FROM AUTHOR]

The killifish Fundulus heteroclitus is abundant in osmotically dynamic estuaries and it can quickly adjust to extremes in environmental salinity. We performed a comparative osmotic challenge experiment to track the transcriptomic and physiological responses to two salinities throughout a time course of acclimation, and to explore the genome regulatory mechanisms that enable extreme osmotic acclimation. One southern and one northern coastal population, known to differ in their tolerance to hypo-osmotic exposure, were used as our comparative model. Both populations could maintain osmotic homeostasis when transferred from 32 to 0.4 p.p.t., but diverged in their compensatory abilities when challenged down to 0.1 p.p.t., in parallel with divergent transformation of gill morphology. Genes involved in cell volume regulation, nucleosome maintenance, ion transport, energetics, mitochondrion function, transcriptional regulation and apoptosis showed population- and salinity-dependent patterns of expression during acclimation. Network analysis confirmed the role of cytokine and kinase signaling pathways in coordinating the genome regulatory response to osmotic challenge, and also posited the importance of signaling coordinated through the transcription factor HNF-4α. These genome responses support hypotheses of which regulatory mechanisms are particularly relevant for enabling extreme physiological flexibility. [ABSTRACT FROM AUTHOR]

Abstract: The rate of acid-stimulated and phenamil-sensitive sodium (Na+) uptake was measured in three different cell lineages: pavement cells (PVC), total mitochondrion-rich (MR) cell populations, and peanut lectin agglutinin-negative mitochondrion-rich cells (PNA− MR) isolated from the rainbow trout gill epithelium. Despite the presence of basal levels of Na+ uptake in PVC, this transport was not enhanced by acidification, nor was it inhibited by independent treatment with bafilomycin (i.e., a V-type H+-ATPase inhibitor), phenamil (i.e., a specific inhibitor of ENaC), or Ag (a specific inhibitor of active Na+ transport in fish). In contrast, Na+ uptake in PNA− MR cells was increased by ~220% above basal levels following acidification of near 0.4 pH units in the presence of 1.0mM external Na+. Acid-stimulated Na+ transport was entirely inhibited by both phenamil and bafilomycin. Silver (Ag) and copper (Cu), which are known to interfere with active Na+ transport in fish, were also responsible for inhibiting acid stimulated Na+ uptake in PNA− MR cells, but by themselves had no effect on basal Na+ transport. Thus, we demonstrate that Ag specifically prevented acid-stimulated Na+ uptake in PNA− MR cells in a dose-dependent manner. We also demonstrate rapid (<1min) and significant inhibition of carbonic anhydrase (CA) by Ag in PNA− MR cells, but not in PVC. These data lend further support to the idea of a PNA− MR cell type as the primary site for Na+ uptake in the freshwater (FW) gill phenotype of rainbow trout. Moreover, these findings provide support for the importance of intracellular protons in regulating the movement of Na+ across the apical surface of the fish gill. [Copyright &y& Elsevier]

Adaptive variation tends to emerge clinally along environmental gradients or discretely among habitats with limited connectivity. However, in Atlantic killifish (Fundulus heteroclitus), a population genetic discontinuity appears in the absence of obvious barriers to gene flow along parallel salinity dines and coincides with a physiologically stressful salinity. We show that populations resident on either side of this discontinuity differ in their abilities to compensate for osmotic shock and illustrate the physiological and functional genomic basis of population variation in hypoosmotic tolerance. A population native to a freshwater habitat, upstream of the genetic discontinuity, exhibits tolerance to extreme hypoosmotic challenge, whereas populations native to brackish or marine habitats downstream of the discontinuity lose osmotic homeostasis mare severely and take longer to recover. Comparative transcriptomics reveals a core transcriptional response associated with acute and acclimatory responses to hypoosmotic shock and posits unique mechanisms that enable extreme osmotic tolerance. Of the genes that vary in expression among populations, those that are putatively involved in physiological acclimation are more likely to exhibit nonneutral patterns of divergence between freshwater and brackish populations. It is not the well-known effectors of osmotic acclimation, but rather the lesser-known immediate early responses, that appear important in contributing to population differences. [ABSTRACT FROM AUTHOR]

Studies a subtype of mitochondria-rich (MR) cells in gills of freshwater rainbow trout using fluorescently labeled peanut lectin agglutinin (PNA-FITC). Change in PNA-FITC binding on filament epithelium with cortisol pretreatment contamination; Evidence for presence of mixed population of chloride and pavement cells in MR cells.

A letter to the editor from the authors of the article "Multitissue Molecular, Genomic, and Developmental Effects of the Deepwater Horizon Oil Spill on Resident Gulf Killifish (Fundulus grandis)" in a 2013 issue is presented.