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Stable oxygen isotopes records (δ18O) in tree-rings are commonly used to assess the response of trees to environmental variability being a valuable tool for studying past climate at different temporal and spatial scales. This is particularly relevant in semi-arid regions like the southern Tropical Andes, where ongoing environmental changes coincide with a rapidly increasing demand for hydrological resources, presenting a challenge for ecosystem dynamics and water resource management. In this study, we aim to determine the main spatio-temporal variability of a new network of δ18O Polylepis tarapacana chronologies during the last century, and their relationships with hydroclimate and tropical circulation at local to subcontinental scales throughout the Tropical Andes. For this purpose, we develop six δ18O P. tarapacana tree-ring chronologies across a 450 km latitudinal moisture gradient in the southern Tropical Andes adjacent to the Atacama Desert, covering the period 1900–2007. Results show a clear latitudinal gradient in the δ18O values across the network and significant relationships are observed with other δ18O tree-ring chronologies in Tropical South America, demonstrating clear regional climate influences at a subcontinental scale. A principal component analysis of the δ18O tree-ring chronologies demonstrate a strong regional environmental signal contained in the network, exhibiting a main temporal pattern (PC1 δ18O) that explains 63% of the total variance during the period 1900–2007. Comparisons between PC1 δ18O and environmental variables showed significant negative relationships with precipitation and soil moisture, and positive relationships with temperature and vapor pressure deficit (VPD) during summer when the South American monsoon occurs. The main δ18O tree-ring network signal clearly records tropical atmospheric and circulation patterns across South America. The easterly wind flux conditions from the Amazon basin favor lower δ18O values, and the PC1 δ18O exhibit significant positive correlations with VPD across the entire Tropical Andes and the northern portion of the Amazon basin, and as well as outgoing longwave radiation across the southern Tropical Andes and part of the Amazon basin. The close relationships between the regional signals from our δ18O tree-ring network with the previously mentioned parameters, highlight the potential to develop future hydroclimatic-related reconstructions with these δ18O records to assess climate variability and change across the Tropical Andes. • A δ18O Polylepis tarapacana tree-ring network is developed in the Southern Tropical Andes. • The δ18O chronologies highlight a strong common signal. • Hydroclimate variability controls δ18O P. tarapacana content across our network. • Tropical atmospheric and circulation patterns show a close relation with δ18O tree-rings. [ABSTRACT FROM AUTHOR]

Simple Summary: Antimicrobial peptides are part of the fish defense system, which can directly eliminate pathogenic microorganisms and, at the same time, regulate the immune response against them. This study evaluated the immunomodulatory effects of the antimicrobial peptide hepcidin in both juvenile fish and fish leukocyte cells. The results showed that hepcidin increased the expression of TNF-α, IL-1β, and IL-10 cytokines in leukocyte cells from trout. Moreover, the mRNA expressions of the same cytokines were up-regulated in different immune tissue of sea bass, confirming in vitro results. This study provides new insights into immunomodulatory function complementary to hepcidin's previously established antimicrobial activity modulating the pro- and anti-inflammatory responses in teleost fish. Antimicrobial peptides (AMP) play an essential role in the innate immune system, modulating the defense response. In a previous study, we demonstrated the antimicrobial activity of synthetic hepcidin (hep20) from rainbow trout (Oncorhynchus mykiss), and its protective effect in European sea bass (Dicentrarchus labrax) challenged with Vibrio anguillarum. Additionally, we described the uptake and distribution of hep20 in different tissues and leukocyte cells. Interestingly, various AMPs characterized in high vertebrates, called host defense peptides (HDPs), also possess immunomodulation activity. For that reason, the present study explores the immunomodulatory abilities of hep20 through in vitro and in vivo studies. First, a monocyte/macrophage RTS-11 cell line from rainbow trout was used to evaluate hep20 effects on pro- and anti-inflammatory cytokines in fish leukocyte cells. Next, the European sea bass juveniles were used to determine if hep20 can regulate the expression of cytokines in fish immune tissues. The results show that hep20 was uptake inner to RTS-11 cells and was able to induce the expression of IL-10, IL-1β, and TNFα at transcriptional and protein levels. Then, the European sea bass juveniles were given intraperitoneal injections of the peptide. At 1, 3, 7, 14, and 21 days post-injection (dpi), IL-10, IL -1β, and TNFα mRNA were quantified in the anterior gut, spleen, and head kidney. The hep20 was able to up-regulate cytokine gene expression in these tissues, mainly in the head kidney. Furthermore, the evaluated cytokines showed a cyclical tendency of higher to lesser expression. Finally, a bioinformatics analysis showed that the structure adopted by hep20 is similar to the γ-core domain described for cysteine-stabilized AMP, defined as immunomodulatory and antimicrobial, which could explain the ability of hep20 to regulate the cytokine expression. This study provides new insights into immunomodulatory function complementary to the previously established antimicrobial activity of hep20, suggesting a role as an HDP in teleost fish. These facts are likely to be associated with molecular functions underpinning the protective effect of fish hepcidin against pathogens. [ABSTRACT FROM AUTHOR]

Simple Summary: Various long-term stress conditions may exist in fish cultivation, damaging the physiological responses that regulate the fish growth and feed. Different signalers connect the brain with the gastrointestinal tract, including the perception of stress factors for the regulation of physiological responses. Here, we evaluated the effect of varying culture densities of Salmo salar post-smolt on the gene expression of some brain and gastrointestinal hormone signalers. We found that high stock densities could promote the levels of molecules associated with feed inhibition, which could be related to the stress pathway regulated by corticoids. Thus, the expression of these peptide hormones could be used as biological markers to improve production practices in fish aquaculture. A variety of long-term stress conditions may exist in fish cultivation, some of which are so severe that fish can no longer reestablish homeostasis. In teleost fish, the brain and gastrointestinal tract integrate signals that include the perception of stress factors regulating physiological responses, such as social stress by fish population density, where peripheral and central signals, such as peptide hormones, are the main regulators. Therefore, we proposed in this study to analyze the effect of different stock densities (SD) in the gene expression of brain neuropeptide Y (NPY) and calcitonin gene-related peptide (CGRP), together with the gastrointestinal peptide hormones leptin (Lep), vasointestinal peptide (VIP), and protachykinin-1 (Prk-1) in Salmo salar post-smolt. The coding sequence of S. salar VIP and Prk-1 precursors were firstly cloned and characterized. Then, the mRNA expression of these genes, together with the NPY, Lep, and CGRP genes, were evaluated in post-smolts kept at 11 Kg/m3, 20 Kg/m3, and 40 Kg/m3. At 14 days of culture, the brain CGRP and liver leptin mRNA levels increased three and tenfold in the post-smolt salmons kept at the highest SD, respectively. The high levels of leptin were kept during all the fish culture experiments. In addition, the highest expression of intestine VIP mRNA was obtained on Day 21 in the group of 40 Kg/m3 returning to baseline on Day 40. In terms of stress biochemical parameters, cortisol levels were increased in the 20 Kg/m3 and 40 Kg/m3 groups on Day 40 and were the highest in the 20 Kg/m3 group on Day 14. This study provides new insight into the gastrointestinal signals that could be affected by chronic stress induced by high stock density in fish farming. Thus, the expression of these peptide hormones could be used as molecular markers to improve production practices in fish aquaculture. [ABSTRACT FROM AUTHOR]

Prumnopitys andina is a South American podocarp with a restricted distribution in southern Andean temperate forests, and is severely threatened due to habitat loss. Despite much dendrochronological work on other temperate South American conifers, little is known about the dendrochronological potential of P. andina. Here, we examine the main features of P. andina tree rings and evaluate the potential of this species for yielding tree-ring chronologies sensitive to climatic variability. In a population at the southern range limit of the species, we collected tree cores and cross-section samples of P. andina for analyses following standard dendrochronological techniques. 76 tree-ring series from 45 trees were examined, 32 (42%) of which were successfully cross-dated and included in a chronology. We found that the species forms well-defined tree rings with distinct boundaries delimiting annual growth. The chronology began in 1778, with notable periods of suppression and release occurring in the late nineteenth and early twentieth centuries, respectively. The chronology showed a high inter-series correlation value of 0.51, suggesting a strong common signal among trees. December to January precipitation showed a positive relationship with radial growth. Conversely, maximum and mean temperature showed negative relationships with radial growth during the austral summer and autumn. These significant relationships of climate variables with radial growth of P. andina indicate that tree-ring series of this species are suitable for dendroclimatological studies. [ABSTRACT FROM AUTHOR]

Nucleotide-binding oligomerization domain (NOD)-like receptors (NLRs) are efficient soluble intracellular sensors that activate defense mechanisms against pathogens. In teleost fish, the involvement of NLRs in the immune response is not well understood. However, recent work has evidenced the expression of different NLRs in response to some pathogen associated molecular patterns (PAMPs). In the present work, the cDNA sequence encoding three new NOD-like receptors were identified in Oncorhynchus mykiss , namely OmNLRC3, OmNLRC5 and OmNLRX1. Results showed that their sequences coded for proteins of 1135, 836 and 1010 amino acids, respectively. The deduced protein sequences of all receptors showed characteristic domains of this receptor family, such as leucine rich repeats and NACHT domain. Phylogenetic analysis revealed a high degree of identity with other NOD-like receptors and they are clustered into different families. Transcript expression analysis indicated that OmNLRs are constitutively expressed in liver, spleen, intestine, gill, skin and brain. OmNLR expression was upregulated in kidney and gills from rainbow trout in response to LPS. In order to give new insights into the function of these new NLR members, an in vitro model of immune stimulation was established using the rainbow trout cell line RTgill-W1. Expression analysis revealed that RTgill-W1 overexpressed proinflammatory cytokines in response to LPS and poly I:C alongside with a differential overexpression of OmNLRC3, OmNLRC5 and OmNLRX1. The expression of OmNLRC5 was further verified at the protein level by immunofluorescence. Finally, the effect of the overexpressed cytokines on the OmNLR expression by RTgill-W1 cells was assessed, suggesting a regulatory mechanism on OmNLRC3 expression. Overall, results suggest that O. mykiss NOD-like receptors could play a key role in the defense mechanisms of teleost through PAMP recognition. Future studies will focus on gills which could be related with a key sensor mucosal system in one of the most environmentally fish exposed tissues. [ABSTRACT FROM AUTHOR]

The croaker Cilus gilberti commonly known as Corvina drum is considered a target marine species for the diversification of Chilean aquaculture. To optimize culture conditions, molecular markers for appetite regulation must be examined. Ghrelin, a gastrointestinal peptide, plays a stimulatory role in the food intake of mammals and teleost fish. Nevertheless, even though the appetite-controlling system is considered relatively well conserved among vertebrates, the bioactivity of these molecules should be analyzed in each fish species. Therefore, this study aimed to investigate the expression and orexigenic ability of C. gilberti ghrelin. After the pre and postprandial period, the stomach expression of ghrelin mRNA in juvenile C. gilberti was analyzed. The coding sequence of C. gilberti ghrelin was used to identify the mature peptide and then chemically synthesized. The orexigenic ability of acylated ghrelin (cgGhre) and non-acylated (D-cgGhre) ghrelin was tested in C. gilberti juveniles. Moreover, the blood and the gastrointestinal location of synthetic ghrelin after intraperitoneal injection were measured. The results showed that the stomach has the highest expression of ghrelin mRNA, and that ghrelin levels increased in the preprandial period and diminished after it. There were no differences in the secondary structure of D-cgGhre compared to cgGhre but the peptide with the serine acylation stabilized its unordered conformation. However, the highest cumulative feed intake occurred in fish intraperitoneally injected with cgGhre. In addition, synthetic ghrelin was maintained in the C. gilberti blood until 8 h post-injection (hpi). Finally, biotinylated ghrelin allowed localizing the synthetic peptide in digestive tissue, mainly in the stomach and pyloric caeca. The mRNA expression of the growth hormone secretagogue receptor (GHS-R), also known as the ghrelin receptor, in gastrointestinal organs supports the idea of peripheral orexigenic regulation in these tissues. In conclusion, results suggest that C. gilberti ghrelin conserves the orexigenic ability reported in other teleost fish with a regulatory role in the gastrointestinal tract (GIT) of the Corvina drum. This is the first report demonstrating the uptake and distribution of a small orexigenic peptide in the digestive tissues of a South American sciaenid. Although ghrelin is a promising molecular marker for feed intake analysis in C. gilberti culture, further research is needed to continue evaluating the effects of aquaculture practices on peripheral appetite signalizer. • The orexigenic ability of ghrelin was demonstrated in juveniles of C. gilberti. • Ghrelin levels in the stomach increased in the preprandial period. • Synthetic ghrelin was localized mainly in the stomach and pyloric caeca. • Ghrelin is a orexigenic regulator of gastrointestinal tract of C. gilberti. [ABSTRACT FROM AUTHOR]

Piscirickettsia salmonis is a facultative intracellular bacterium that causes the disease called “salmon rickettsial syndrome”. Attempts to control this disease have been unsuccessful, because existing vaccines have not achieved the expected effectiveness and the antibiotics used fail to completely eradicate the pathogen. This is in part the product of lack of scientific information that still lacks on the mechanisms used by this bacterium to overcome infected–cell responses and survive to induce a productive infection in macrophages. For that, this work was focused in determining if P. salmonis is able to modify the expression and the imbalance of IL-12 and IL-10 using an in vitro model. Additionally, we also evaluated the role the antimicrobial peptide hepcidin had in the control of this pathogen in infected cells. Therefore, the expression of IL-10 and IL-12 was evaluated at earlier stages of infection in the RTS11 cell line derived from Oncorhynchus mykiss macrophages. Simultaneously, the hepcidin expression and location was analyzed in the macrophages infected with the pathogen. Our results suggest that IL-10 is clearly induced at early stages of infection with values peaking at 36 hours post infection. Furthermore, infective P. salmonis downregulates the expression of antimicrobial peptide hepcidin and vesicles containing this peptide were unable to merge with the infective bacteria. Our results suggest that P. salmonis is able to manipulate the behavior of host cytokines and likely might constitute a virulence mechanism that promotes intracellular bacterial replication in leukocytes cells lines of trout and salmon. This mechanism involves the generation of an optimum environment for the microorganism and the downregulation of antimicrobial effectors like hepcidin. [ABSTRACT FROM AUTHOR]

The generation of a variety of new therapeutic agents to control and reduce the effects of pathogen in aquaculture is urgently needed. The antimicrobial peptides (AMPs) are one of the major components of the innate defenses and typically have broad-spectrum antimicrobial activity. However, absorption and distributions of exogenous AMPs for therapeutics application on farmed fish species need to be studied. Previous studies in our laboratory have shown the properties of hepcidin as an effective antimicrobial peptide produced in fish in response to LPS and iron. Therefore, we decided to investigate the antimicrobial activity of four synthetic variants of hepcidin against Vibrio anguillarum in vitro , and using the more effective peptide we demonstrated the pathogen’s ability to protect against the infection in European Sea bass. Additionally the uptake of this peptide after ip injection was demonstrated, reaching its distribution organs such as intestine, head kidney, spleen and liver. The synthetic peptide did not show cytotoxic effects and significantly reduced the accumulated mortalities percentage (23.5%) compared to the European Sea bass control (72.5%) at day 21. In conclusion, synthetic hepcidin shows antimicrobial activity against V. anguillarum and the in vivo experiments suggest that synthetic hepcidin was distributed trough the different organs in the fish. Thus, synthetic hepcidin antimicrobial peptide could have high potential for therapeutic application in farmed fish species. [ABSTRACT FROM AUTHOR]

Hepcidin is an antimicrobial peptide and a hormone produced mostly the liver. It is a cysteine-rich peptide with a highly conserved β-sheet structure. Recently, we described the hepcidin expression in liver of rainbow trout and its inducibility by iron overloading and lipopolysaccharide (LPS). Thus, in this work, we focused in analyzing the importance of the peptide conformation associated to its oxidative state in the antimicrobial activity. This peptide showed a α-helix conformation in reduced state and the characteristic β-sheet conformation in the oxidized state. Antimicrobial activity assays showed that the oxidized peptide is more effective than the reduced peptide against Escherichia coli and the important salmon fish pathogen Piscirickettsia salmonis. In addition, confocal analysis of P. salmonis culture exposed to trout hepcidin coupled with rhodamine revealed the intracellular location of this peptide and Sytox permeation assay showed that membrane disruption is not the mechanism of its antimicrobial action. Moreover, a conserved ATCUN motif was detected in the N-terminus of this peptide. This sequence has been described as a small metal-binding site that has been implicated in DNA cleavage. In this work we proved that this peptide is able to induce DNA hydrolysis in the presence of ascorbate and CuCl 2 . When the same experiments were carried out using a variant with truncated N-terminus no DNA hydrolysis was observed. Our results suggest that correct folding of hepcidin is required for its antimicrobial activity and most likely the metal-binding site (ATCUN motif) present in its N-terminus is involved in the oxidative damage to macromolecules. [ABSTRACT FROM AUTHOR]

Abstract: One of the most widespread antimicrobial peptides (AMPs) in fish is the hepcidins, which have potent, broad-spectrum activity against viruses, bacteria, fungi, and parasites. Moreover, they play the role of central regulation of iron metabolism and their expression is over-regulated by bacterial and viral infections, inflammation and vaccination. Quantification of their expression is an important factor in understanding their function. We therefore generated two polyclonal antibodies using synthetic peptides in order to measure hepcidin expression via sandwich ELISA. The specificity of both antibodies was confirmed by identifying an absence of cross-reactivity with other peptides that have similar pI and with the detection by Western blot of only one 9.6 kDa immunoreactive band corresponding to the hepcidin prepropeptide. The sensitivity of the sandwich ELISA was in the order of 0.005 ng/μL of hepcidin, which allowed analysis of the presence of the peptide and its variation in different tissues of Oncorhynchus mykiss. With the sandwich ELISA it could be seen that hepcidin expression in rainbow trout challenged with Aeromonas salmonicida was increased twofold over the untreated fish in head kidney samples, in correlation with the increase in the observed transcriptional level in the head kidney cells. These results provide the first evidence for quantifying the presence of active hepcidin and may be a useful indicator of disease susceptibility, providing a new, sensitive tool for rapid screening of population health. [Copyright &y& Elsevier]

Highlights: [•] We report an antibody against hepcidin mature peptide from rainbow trout. [•] The antibody detect the prepropeptide in rainbow trout liver. [•] The hepcidin prepropeptide was induced by iron overloading and LPS. [•] The mature peptide was identifying by mass spectrometry analyses. [•] Hepcidin could be a molecular marker with application in aquaculture and fish health. [Copyright &y& Elsevier]

α-Enolase is an enzyme of the glycolytic pathway that has also been involved in vertebrate inflammatory processes through its interaction with plasminogen. However, its participation in the immune response of lower vertebrates during early life development is unknown. Opportunistic pathogens in salmon farming are the principal cause of mortality in the fry stage. For that reason, molecular indicators of their immunological status are required to ensure the success of the large-scale cultivation. Thus, the objective of this work was to analyze if ENO-1 is involved in the immune response of rainbow trout fry. For this purpose, the coding sequence of trout ENO-1 was characterized, identifying the plasminogen-binding domain that has been described for homologs of this enzyme in higher vertebrates. A peptide-epitope of α-enolase was used for producing mice antiserum. The specificity of polyclonal antibodies was confirmed by dot blot, ELISA and Western blot. Then, the antiserum was used to evaluate α-enolase expression in fry between 152 and 264 degree-days post-hatching after 2, 8, and 12 h of challenge with lipopolysaccharide from Pseudomona auroginosa. The expression of α-enolase at both transcriptional (RT-qPCR) and protein (ELISA) levels was significantly increased after 8 h post-challenge with lipopolysaccharide. These results were confirmed by proteomic analysis by 2D-difference gel electrophoresis (DIGE). This work provides the first evidence of the involvement of α-enolase in the early immune response of salmonids. Future research will be required to understand the possible interaction of α-enolase with plasminogen in cells and tissues of the salmonid immune system. • The putative plasminogen-binding motif was identified in trout ENO-1. • Specific mouse antisera against ENO-1 of trout was characterized. • Trout ENO-1 was up-regulated at 8 h in response to LPS. • 2D-DIGE analysis confirmed the ENO-1 increasing in trout fry stimulated with LPS. [ABSTRACT FROM AUTHOR]

Simple Summary: In mammals, autophagy plays a fundamental role in the defense against intracellular pathogens; however, in fish, this noncanonical function has not been described. In this context, it was proposed to study whether autophagy was modulated/activated in muscle cells challenged with a bacterial pathogen. Muscle cell cultures were performed and challenged with Piscirickettsia salmonis, the main threat to the salmon industry. Genes associated with immune response and autophagy were evaluated. In addition, the protein content of the LC3-II-specific marker of the autophagic process was evaluated via Western blot. Additionally, genes associated with vesicular traffic and endocytosis were evaluated, finding that P. salmonis promotes these processes. The results show a concomitant modulation of the genes associated with the immune response, vesicular trafficking, and autophagy, suggesting an early intracellular response by the muscle cell against this bacterium. Due to the necessity of seeking and discovering new alternatives and strategies to fight intracellular pathogens in the salmon industry, a better understanding of how autophagy participates in immune system responses may lead to the development of new technologies that allow for the effective control of intracellular pathogens, improving animal welfare and contributing to the sustainability of the global fish industry. Autophagy is a fundamental cellular process implicated in the health of the cell, acting as a cytoplasmatic quality control machinery by self-eating unfunctional organelles and protein aggregates. In mammals, autophagy can participate in the clearance of intracellular pathogens from the cell, and the activity of the toll-like receptors mediates its activation. However, in fish, the modulation of autophagy by these receptors in the muscle is unknown. This study describes and characterizes autophagic modulation during the immune response of fish muscle cells after a challenge with intracellular pathogen Piscirickettsia salmonis. For this, primary cultures of muscle cells were challenged with P. salmonis, and the expressions of immune markers il-1β, tnfα, il-8, hepcidin, tlr3, tlr9, mhc-I and mhc-II were analyzed through RT-qPCR. The expressions of several genes involved in autophagy (becn1, atg9, atg5, atg12, lc3, gabarap and atg4) were also evaluated with RT-qPCR to understand the autophagic modulation during an immune response. In addition, LC3-II protein content was measured via Western blot. The challenge of trout muscle cells with P. salmonis triggered a concomitant immune response to the activation of the autophagic process, suggesting a close relationship between these two processes. [ABSTRACT FROM AUTHOR]

Simple Summary: The salmonid industry is susceptible to opportunistic pathogens particularly affecting fish in early developmental stages. Understanding the immunological capacity during these stages is crucial for effective disease control. The receptor for Interleukin 8 (CXCR1), plays a key role in various inflammatory conditions. This study analyzed the expression of IL-8R and IL8 in rainbow trout larvae in response to bacterial lipopolysaccharide (LPS). The larvae 19 day post-hatching (dph) exhibited strong immune responses after 8 h of LPS stimulation, with IL-8 and omCXCR1 protein expression increasing. The use of specific antisera allowed localization of both proteins in mucosal tissue cells. This study highlights the effectiveness of LPS immersion in activating the innate immune system of trout larvae using IL-8/CXCR1 as immunological markers. The salmonid industry faces challenges due to the susceptibility of fish to opportunistic pathogens, particularly in early developmental stages. Understanding the immunological capacity during these stages is crucial for developing effective disease control strategies. IL-8R, a member of the G-protein-coupled receptor family, acts as a receptor for Interleukin 8 (IL-8). The binding of IL-8 to IL-8R plays a major role in the pathophysiology of a wide spectrum of inflammatory conditions. This study focused on the immune response capacity of rainbow trout (Oncorhynchus mykiss) larvae by analyzing IL-8/CXCR1 response to lipopolysaccharide (LPS) from Pseudomonas aeruginosa. Previous research demonstrated that LPS from P. aeruginosa acts as a potent immunostimulant in teleost, enhancing pro-inflammatory cytokines. The methodology included in silico analysis and the synthesis and characterization of an omCXCR1-derived epitope peptide, which was used to produce omCXCR1-specific anti98 serum in mice. The research revealed that rainbow trout larvae 19 days post-hatching (dph) exhibited pronounced immune responses post-stimulation with 1 µg/mL of LPS. This was evidenced by the upregulated protein expression of IL-8 and omCXCR1 in trout larvae 2 and 8 h after LPS challenge, as analyzed by ELISA and immunohistochemistry. Furthermore, fluorescence microscopy successfully revealed the colocalization of IL-8 and its receptor in cells from mucosal tissues after LPS challenge in larvae 19 dph. These findings underscore the efficacy of LPS immersion as a method to activate the innate immune system in trout larvae. Furthermore, we propose IL-8 and its receptor as molecular markers for evaluating immunostimulation in the early developmental stages of salmonids. [ABSTRACT FROM AUTHOR]

The discovery and improvements of antimicrobial peptides (AMPs) have become an alternative to conventional antibiotics. They are usually small and heat-stable peptides, exhibiting inhibitory activity against Gram-negative and Gram-positive bacteria. In this way, studies on broad-spectrum AMPs found in amphibians with the remarkable capability to regenerate a wide array of tissues are of particular interest in the search for new strategies to treat multidrug-resistant bacterial strains. In this work, the use of bioinformatic approaches such as sequence alignment with Fasta36 and prediction of antimicrobial activity allowed the identification of the Ramosin peptide from the de novo assembled transcriptome of the plethodontid salamander Bolitoglossa ramosi obtained from post-amputation of the upper limb tissue, heart, and intestine samples. BLAST analysis revealed that the Ramosin peptide sequence is unique in Bolitoglossa ramosi. The peptide was chemically synthesized, and physicochemical properties were characterized. Furthermore, the in vitro antimicrobial activity against relevant Gram-positive and Gram-negative human pathogenic bacteria was demonstrated. Finally, no effect against eukaryotic cells or human red blood cells was evidenced. This is the first antibacterial peptide identified from a Colombian endemic salamander with interesting antimicrobial properties and no hemolytic activity. [ABSTRACT FROM AUTHOR]

The croaker Cilus gilberti is an important coastal food fish in Chile and Peru, and is being considered as a target marine species for diversification of Chilean aquaculture. In order to optimize culture, responses to density and potential environmental rearing conditions must be examined. Stocking density (SD) is an important factor for cultivation-related economic viability, because inappropriate SD is frequently associated with an increase of size heterogeneity, modification of social interactions and reduction of flesh quality. In addition, drastic decreases in dissolved oxygen are one of the major recurrent environmental stress factors in the area of choice for C. gilberti farming in the north of Chile, thus studies on responses to hypoxia and their associations with SD are required. Therefore, in this study, C. gilberti juveniles prior to stocking into grow-out pens were maintained for 120 days at three different stocking densities: 15 kg/m3 (LSD), 25 kg/m3 (MSD) and 35 kg/m3 (HSD), and then exposed to an acute hypoxia event. Biometric parameters, flesh quality, blood and liver biochemical parameters, and molecular markers of growth performance and stress responses were analyzed. Surprisingly, the highest body weight gain occurred in fish held at the highest density. In terms of growth-related genes, levels of growth hormone mRNA were not different between stocking densities, but liver insulin-like growth factor 1 (IGF-1) mRNA levels increased with SD and were the highest in the HSD group. There were no differences in flesh proximate composition. Similarly, glucose, lactate and HSP70 levels measured to assess chronic stress were not different among densities. There was a notable increase in lactate levels of fish in the HSD group in response to acute hypoxia, which suggests a greater reliance on anaerobic glycolysis by this group. In conclusion, results suggest that C. gilberti juveniles tolerate high stocking densities (at least 35 kg/m3) without generating chronic stress or decreasing their capacity to respond to acute hypoxia; and high SD would be preferable due to better growth. Although present results are promising, further research is needed to continue with the standardization of the SD that will allow the best productive yield of this new fish species for Chilean aquaculture. • C. gilberti growth and IGF-1 mRNA levels increased with stocking density. • Stocking density did not affect flesh proximate composition. • High stocking density did not induce physiological chronic stress response. • High stocking density did not affect the capacity to respond to acute hypoxia. • C. gilberti juveniles can be maintained at high stocking in extensive pond systems. [ABSTRACT FROM AUTHOR]

The elder (Sambucus spp.) tree has a number of uses in traditional medicine. Previous studies have demonstrated the antimicrobial properties of elderberry liquid extract against human pathogenic bacteria and also influenza viruses. These properties have been mainly attributed to phenolic compounds. However, other plant defense molecules, such as antimicrobial peptides (AMPs), may be present. Here, we studied peptide extracts from flowers of Sambucus nigra L. The mass spectrometry analyses determined peptides of 3 to 3.6 kDa, among them, cysteine-rich peptides were identified with antimicrobial activity against various Gram-negative bacteria, including recurrent pathogens of Chilean aquaculture. In addition, membrane blebbing on the bacterial surface after exposure to the cyclotide was visualized by SEM microscopy and SYTOX Green permeabilization assay showed the ability to disrupt the bacterial membrane. We postulate that these peptides exert their action by destroying the bacterial membrane. [ABSTRACT FROM AUTHOR]

Cyclotides are circular peptides found in various plant families. A cyclized backbone, together with multiple disulfide bonds, confers the peptides’ exceptional stability against protease digestion and thermal denaturation. In addition, the features of these antimicrobial molecules make them suitable for use in animal farming, such as aquaculture. Fmoc solid phase peptide synthesis on 2-chlorotrityl chlorine (CTC) resin using the “tea-bag” approach was conducted to generate the VarvA cyclotide identified previously from Viola arvensis. MALDI-TOF mass spectrometry determined the correct peptide amino acid sequence and the cyclization sites-critical in this multicyclic compound. The cyclotide showed antimicrobial activity against various Gram-negative bacteria, including recurrent pathogens present in Chilean aquaculture. The highest antimicrobial activity was found to be against Flavobacterium psychrophilum. In addition, membrane blebbing on the bacterial surface after exposure to the cyclotide was visualized by SEM microscopy and the Sytox Green permeabilization assay showed the ability to disrupt the bacterial membrane. We postulate that this compound can be proposed for the control of fish farming infections. [ABSTRACT FROM AUTHOR]

Currently, one of the primary challenges in salmon farming is caligidosis, caused by the copepod ectoparasites Caligus spp. The infection process is determined by the copepod's ability to adhere to the fish skin through the insertion of its chitin-composed filament. In this study, we examined several antimicrobial peptides previously identified in salmonid mucosal secretions, with a primary focus on their potential to bind to chitin as an initial step. The binding capacity to chitin was tested, with hepcidin and piscidin showing positive results. Further assessments involving cytotoxicity in salmonid cells RTgill-W1, SHK-1, RTS-11, and RT-gut indicated that the peptides did not adversely affect cell viability. However, hemolysis assays unveiled the hemolytic capacity of piscidin at lower concentrations, leading to the selection of hepcidin for antiparasitic assays. The results demonstrated that the nauplius II stage of C. rogercresseyi exhibited higher susceptibility to hepcidin treatments, achieving a 50% reduction in parasitic involvement at 50 µM. Utilizing fluorescence and scanning electron microscopy, we observed the localization of hepcidin on the surface of the parasite, inducing significant spherical protuberances along the exoskeleton of C. rogercresseyi. These findings suggest that cysteine-rich AMPs derived from fish mucosa possess the capability to alter the development of the chitin exoskeleton in copepod ectoparasites, making them therapeutic targets to combat recurrent parasitic diseases in salmon farming. [ABSTRACT FROM AUTHOR]

In this work, the potential antimicrobial role and mechanism of action of α-helix domain of trout and salmon IL-8 against Eschericia coli , Pseudomonas aeruginosa and Staphylococcus aureus was investigated. By an in silico analysis of the primary structure of IL-8 from Oncorhynchus mykiss and salmo salar , it was evidenced that γ-core motif was present, as in the vast majority of kinocidins. The α-helix domain of IL-8 (αIL-8) was synthesized by solid phase peptide synthesis and showed a tendency to form an α-helix conformation, as revealed by circular dichroism. Additionally, it was demonstrated that αIL-8 from both species showed antimicrobial activity against E. coli , P. aeruginosa and S. aureus . Membrane permeabilization and co-localization assay, as well as scanning electron microscopy, showed that these peptides were accumulated on the cell surface and in the cytoplasm, suggesting that they were capable of permeabilizing and disrupt the bacterial membranes and interact with cytoplasmic components. Our results represent the first analysis on the antimicrobial function of IL-8-derived peptide from salmonids. [ABSTRACT FROM AUTHOR]

Scallop aquaculture is threatened by Vibrio bacteria-induced larval mortality, needing the development of sustainable pathogen control strategies. This study investigates the potential of host-derived antimicrobial peptides (AMPs) as eco-friendly alternatives for pathogen control in aquaculture. Exploiting the scallop transcriptome, we identified sequences sharing common AMP features and designed a de novo peptide named helixidin, a 40-amino acid peptide with a net charge of +11 and a pI of 11.52. In addition, we designed an analog, N-ter Ap BD Q13R, based on the hydrophobic domain of the scallop big defensin Ap BD, with a glutamine-to-arginine substitution at position 13. N-ter Ap BD Q13R is a 35-residue peptide with a net charge of +4 and a pI of 11.55. The synthetic peptides helixidin and N-ter Ap BD Q13R adopted an alpha-helix secondary structure with an amphiphilic distribution of amino acid residues. Circular dichroism assays confirmed their structural stability across varying pH, osmolarity, and temperature conditions. Moreover, these peptides displayed potent broad-spectrum antibacterial activity, in the case of helixidin causing cell wall and membrane disruption of Gram-positive and Gram-negative bacteria, respectively. On the other hand, N-ter Ap BD Q13R showed a possible penetrating action on bacterial cells, with formation of nanonets-like structures against the scallop pathogen Vibrio bivalvicida VPAP30. Notably, both peptides exhibited selective activities against Vibrio strains isolated from healthy scallop larvae and specific bivalve pathogenic Vibrio , underscoring their potential for targeting host-associated vibrios. Biosafety tests showed that both peptides are harmless to A. purpuratus larvae. In conclusion, helixidin and N-ter Ap BD Q13R represent novel cationic AMPs with different mechanisms of action against host-associated vibrios, offering promising prospects for sustainable pathogen control in scallop aquaculture. • Two novel AMP derived from the scallop A. purpuratus transcriptome were designed. • Synthetic helixidin and N-ter Ap BD Q13R are alpha helical peptides with broad thermal stability. • Both synthetic peptides showed selected antibacterial activity against pathogenic Vibrio strains. • Helixidin destroys the wall and membrane of bacteria, while N-ter Ap BD Q13R possibly has penetrating action. • Both synthetic peptides are innocuous for larvae of A. purpuratus. [ABSTRACT FROM AUTHOR]

The goals of this study were to assess the behavior, dynamics and sustainability of populations of Dalea lutea (Cav.) Wild. in mixed forest and grassland under natural conditions and of recollection. The investigation was carried out in a pine-oak forest near Tenancingo, Mexico State (Mexico), from Autumn 2002 to Autumn 2004. Four plots were marked in each zone and the individuals counted were classified in three types: seedlings, young and adults; the data were subject to analysis of variance, test of means and sustainability formulae. The population Dalea lutea increased in summer-autumn and decreased in winter-spring. Samplings showed statistical differences for seedlings and young, but not for adults, but when these classes were evaluated within zones they did not differ statistically; the largest number of individuals was reported during summer, autumn and winter of 2003. Regarding sustainability, there was a reestablishment within the pasture at the end of the period of 59.5 and 41% for seedlings and adults, respectively, and a reduction of 79% in young individuals; in the mixed forest, seedlings and the young plants decreased by 4.4 and 16.2%, while adults recovered in 25.1%. The population of Dalea lutea increased or decreased according to the time of sampling, and the number of individuals was determined by precipitation. Under the current conditions of collection, D. lutea population remains stable in the mixed forest and it is recovering better in the grassland. [ABSTRACT FROM AUTHOR]

Background: In fish farming, the plant extracts containing antioxidant compounds have been added to the diet for enhancing pathogen resistance. In vitro studies evaluating the antioxidant effect of herbal extracts on fish cell models have focused on ROS production and the respiratory burst mechanism. However, the effects on enzymatic antioxidant defense on salmon leukocytes have not been evaluated. This study aims to evaluate the enzymatic antioxidant defense and ROS-induced cell damage in Salmon Head Kidney-1 (SHK-1) cell line exposed to polyphenol-enriched extract from Sambucus nigra flowers. Results: Firstly, the Total Reactive Antioxidant Power (TRAP) assay of elderflower polyphenol (EP) was evaluated, showing 459 and 489 times more active than gallic acid and butyl hydroxy toluene (BHT), respectively. The toxic effect of EP on salmon cells was not significant at concentrations below 120 mg/mL and no hemolysis activity was observed between 20 and 400 mg/mL. The treatment of SHK-1 cell line with EP decreased both the lipid peroxidation and protein oxidation induced by H2O2, which could be associated with decreasing oxidative stress in the SHK-1 cells since the GSH/GSSG ratio increased when only EP was added. Conclusions: These results suggest that plant extracts enriched with polyphenols could improve the enzymatic antioxidant defense of salmon leukocytes and protect the cells against ROS-induced cell damage. [ABSTRACT FROM AUTHOR]

Waste Tyres (WT) are a significant fraction of industrial waste and a source of environmental hazards with limited valorisation. To reduce this problem, currently there is a growing interest in valuing the WT through pyrolysis to obtain multifunctional liquids to improve the rheological and self-healing properties of aged binders. This research provides a comprehensive study on using WT mixtures as precursors for asphalt rejuvenators by means of pyrolysis and distillation processes. To this end, WT polymeric fractions from light (WT-L) and mining trucks (WT-M) were used as feedstock and characterised for compositional and thermal properties. Additionally, micropyrolysis coupled with gas chromatography/mass spectrometry (Py-GC-MS) was used to identify the major products in pyrolysis vapours, to elucidate the reaction maps describing thermal degradation of WTs and to predict the feasible reaction conditions. The pyrolysis liquids were produced after a screening of reaction conditions and subjected to distillation, following a response surface model to produce an optimised pyro-rejuvenator. The results showed that the pyrolytic rejuvenator obtained through pyrolysis at 465 °C and distillation cutting at 160–200 °C is mainly composed of hydrocarbons and aromatic substances (95.5%), with a significant proportion of limonene (33.71%). Furthermore, the pyrolytic rejuvenator exhibited highly desirable physical properties in the context of its application and excellent oxidative stability (85.7%). Otherwise, it was determined that bitumen mixtures with 3%–6% doses of pyro-rejuvenator improved the viscosity, softening point, and penetration of aged binders, restoring their physical properties to the virgin state. In conclusion, pyro-rejuvenators can be successfully used as a promising solution to produce more durable and sustainable pavements with improved rheological and healing properties. [Display omitted] • Waste tyres rubber composition was studied through a TGA-kinetic approach. • Py-GC/MS demonstrated a synergistic effect between natural rubber and additives. • Optimal rejuvenator's composition is controlled by coupling pyrolysis with distillation. • Pyro-rejuvenator dosages of 3%–6% are optimal for healing aged asphalts. • Pyro-rejuvenator restores the aged asphalt from PAV to its virgin state. [ABSTRACT FROM AUTHOR]

Several factors have influenced the increasing presence of peptides as an important class of Active Pharmaceutical Ingredients. One is the continued development of synthetic methodologies for peptide synthesis. Herein, we investigated the Fmoc removal step, using the tea-bag strategy. In this regard, three different secondary amines: piperidine, 4-methylpiperidine, and piperazine, were evaluated. As a result of this study, 4-methyl piperidine showed to be an excellent alternative to the usually used piperidine in terms of purity and compliance with green chemistry principles as well. [ABSTRACT FROM AUTHOR]

Inter-Organizational Information Systems (IOISs) for seaport logistics facilitate monitoring operations, the exchange of information with stakeholders, and meeting regulations of foreign trade. However, seaport contexts entail complexities in terms of stakeholder involvement and business processes that must be considered thoroughly toward the successful adoption of IOISs. This research seeks to identify factors influencing the successful adoption of IOISs in seaports. It follows a grounded theory approach relying on semi-structured interviews and expert opinions to identify facilitating conditions for the adoption of IOISs. Survey research was conducted in order to investigate the appraisal of different ports in Latin America and the Caribbean region regarding the diverse conditions. The results obtained were analyzed descriptively and through a Principal Components Analysis. The latter was conducted in order to discern relevant dimensions influencing the adoption of IOISs in seaports. The results of the study allow deriving managerial insights and practical recommendations to support technological plans at ports and guide the decision-making regarding the digitalization process. [ABSTRACT FROM AUTHOR]

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder among reproductive-aged women and the main cause of infertility due to anovulation. However, this syndrome spans the lives of women affecting them from in-utero life until death, leading to several health risks that can impair quality of life and increase morbidity and mortality rates. Fetal programming may represent the beginning of the condition characterized by hyperandrogenism and insulin resistance which leads to a series of medical consequences in adolescence, adulthood, and old age. Menstrual and fertility problems evolve into metabolic complications as age advances. An early and precise diagnosis is important for an adequate management of PCOS, especially at the extreme ends of the reproductive lifespan. However, many different phenotypes are included under the same condition, being important to look at these different phenotypes separately, as they may require different treatments and have different consequences. In this way, PCOS exhibits a great metabolic complexity and its diagnosis needs to be revised once again and adapted to recent data obtained by new technologies. According to the current medical literature, lifestyle therapy constitutes the first step in the management, especially when excess body weight is associated. Pharmacotherapy is frequently used to treat the most predominant manifestations in each age group, such as irregular menses and hirsutism in adolescence, fertility problems in adulthood, and metabolic problems and risk of cancer in old age. Close surveillance is mandatory in each stage of life to avoid health risks which may also affect the offspring, since fetal and post-natal complications seem to be increased in PCOS women. [ABSTRACT FROM AUTHOR]

Previous work demonstrated that Lys homopeptides with an odd number of residues (9, 11 and 13) were capable of inhibiting the growth of Gram-positive bacteria in a broader spectrum and more efficiently than those with an even number of Lys residues or Arg homopeptides of the same size. Indeed, all Gram-positive bacteria tested were totally inhibited by 11-residue Lys homopeptides. In the present work, a wide variety of Gram-negative bacteria were used to evaluate the inhibitory activity of chemically synthesized homopeptides of l-Lys and l-Arg ranging from 7 to 14 residues. Gram-negative bacteria were comparatively more resistant than Gram-positive bacteria to Lys homopeptides with an odd number of residues, but exhibited a similar inhibition pattern than on Gram-positive bacteria. CD spectra for the odd-numbered Lys homopeptides in anionic lipid dimyristoylphosphatidylglycerol, and Escherichia coli membrane extract increased polyproline II content, as compared to those measured in phosphate buffer solution. Lys and Arg homopeptides were covalently linked to rhodamine to visualize the peptide interactions with E. coli cells using confocal laser scanning microscopy. Analysis of Z-stack images showed that Arg homopeptides indeed appear to be localized intracellularly, while the Lys homopeptide is localized exclusively on the plasma membrane. Moreover, these Lys homopeptides induced membrane disruption since the Sytox fluorophore was able to bind to the DNA in E. coli cultures. [ABSTRACT FROM AUTHOR]

Abstract: Deep-sea ecosystems are highly diverse, and European countries seek to protect these environments by identifying conservation targets. One of these is the Avilés Canyon, southern Bay of Biscay, NE Atlantic, Spain. We present the first analysis of historical benthic communities (1987–1988) of this canyon ecosystem, which is a valuable source of biodiversity baseline information. We found 810 taxa divided in five main macrobenthic assemblages, showing a highly diverse benthic community. Bathymetry was the major structuring agent of benthic community, separating shallow (assemblages I and II, 31 to 307m depth) from deep stations (assemblages III, IV and V, 198 to 1400m depth). Especially diverse was assemblage IV, located at the easternmost part of the continental slope (378–1100m depth) where we found reef-forming corals Lophelia pertusa and Madrepora oculata. These and other communities (sea-pens [Order Pennatulacea, Phylum Cnidaria] and burrowing macrofauna) represent key habitats in NE Atlantic continental slopes, which are currently threatened. The present dataset has produced the most comprehensive assessment of diversity in this area to date, focusing on the taxonomic groups which may best reflect the health of the marine ecosystem and supporting previous studies which indicate that the continental slope of the southern Bay of Biscay hosts key benthic habitats. [Copyright &y& Elsevier]

Ovarian hyperstimulation syndrome (OHSS) is an iatrogenic complication of ovulation induction, which may seriously affect the patient's health, with 0.1-2.0% of the patients developing severe forms of the syndrome. OHSS signs and symptoms are direct consequences of fluid shift from capillaries to the third space due to increased vascular permeability. The mechanisms of OHSS pathophysiology remain unknown but evidence obtained in animal models prove that vascular endothelial growth factor (VEGF) is directly involved and the inhibition of the VEGF system could prevent OHSS from occurring. Dopamine agonists impede the phosphorylation of the VEGF receptor 2 and reduce the incidence and severity of OHSS with a safe clinical profile. As far as is known, this is the first pathophysiological approach for treatment and prevention of OHSS. [ABSTRACT FROM AUTHOR]

Understanding environmental constraints and associated physiological adaptations of culture organisms is key for the implementation of off-shore grow-out facilities. In the southeast Pacific Ocean along the coasts of Chile and Peru, seasonal upwelling events lead to hypoxic conditions, which are projected to increase in both frequency and intensity with climate change. Aquaculture operations must take into account the physiological adaptability of a species for environmental conditions. For Cojinoba (Seriolella violacea), a native target species for aquaculture diversification in northern Chile, little is known in regard to physiological capacity for hypoxia. Therefore, hypoxia tolerance studies were conducted followed by measurement of resting and active metabolism and associated energy facilitation in response to hypoxia in juvenile Cojinoba. Hypoxia tolerance studies found they were resilient to dissolved oxygen levels of 1.0 mg O 2 Lˉ1 for 8 h. Swimming metabolism studies exposed Cojinoba to normoxia (7.5 mg O 2 Lˉ1) or hypoxia (1.0 mg O 2 Lˉ1), and quantified minimum metabolic rate (MO 2 min), active metabolic rate (MO₂ max), critical swimming speed (U crit) and associated energetic metabolites and hematological variables. In hypoxia, there was a decrease in MO₂ max (34%) leading to a large (82%) decrease in aerobic metabolic scope. MO 2 min decreased as well by 12%, with lactate increasing presumably to temporarily maintain basic metabolic function. In addition, U crit decreased by 53% in hypoxia, although tail beat frequency was similar in normoxia and hypoxia up to a velocity of 40 cm s−1. Moreover, although erythrocyte concentration increased in hypoxia, hemolysis was observed in exercised fish in this condition. There was a notable increase (5-fold compared to normoxia) in lactate levels of exercised fish in the hypoxia group, which suggests a quick conversion to anaerobic metabolic pathways to maintain energy balance when swimming in hypoxic environments. Therefore, Cojinoba have adaptive responses that may facilitate survival during severe hypoxic events although overall physiological performance is diminished. • Effects of hypoxia on the physiological capacity were established for juvenile Cojinoba, Seriolella violacea. • Hypoxia (1.0 mg O 2 / L) significantly reduced MO₂ max and Ucrit • Metabolism during hypoxia is sustained by decreased MO 2 min and anaerobic glycolysis • Cojinoba have adaptive responses that may facilitate survival during severe hypoxic events [ABSTRACT FROM AUTHOR]

Understanding environmental constraints and associated physiological adaptations of culture organisms is key for the implementation of off-shore grow-out facilities. In the southeast Pacific Ocean along the coasts of Chile and Peru, seasonal upwelling events lead to hypoxic conditions, which are projected to increase in both frequency and intensity with climate change. Aquaculture operations must take into account the physiological adaptability of a species for environmental conditions. For Cojinoba (Seriolella violacea), a native target species for aquaculture diversification in northern Chile, little is known in regard to physiological capacity for hypoxia. Therefore, hypoxia tolerance studies were conducted followed by measurement of resting and active metabolism and associated energy facilitation in response to hypoxia in juvenile Cojinoba. Hypoxia tolerance studies found they were resilient to dissolved oxygen levels of 1.0 mg O 2 Lˉ1 for 8 h. Swimming metabolism studies exposed Cojinoba to normoxia (7.5 mg O 2 Lˉ1) or hypoxia (1.0 mg O 2 Lˉ1), and quantified minimum metabolic rate (MO 2 min), active metabolic rate (MO₂ max), critical swimming speed (U crit) and associated energetic metabolites and hematological variables. In hypoxia, there was a decrease in MO₂ max (34%) leading to a large (82%) decrease in aerobic metabolic scope. MO 2 min decreased as well by 12%, with lactate increasing presumably to temporarily maintain basic metabolic function. In addition, U crit decreased by 53% in hypoxia, although tail beat frequency was similar in normoxia and hypoxia up to a velocity of 40 cm s−1. Moreover, although erythrocyte concentration increased in hypoxia, hemolysis was observed in exercised fish in this condition. There was a notable increase (5-fold compared to normoxia) in lactate levels of exercised fish in the hypoxia group, which suggests a quick conversion to anaerobic metabolic pathways to maintain energy balance when swimming in hypoxic environments. Therefore, Cojinoba have adaptive responses that may facilitate survival during severe hypoxic events although overall physiological performance is diminished. • Effects of hypoxia on the physiological capacity were established for juvenile Cojinoba, Seriolella violacea. • Hypoxia (1.0 mg O 2 / L) significantly reduced MO₂ max and Ucrit • Metabolism during hypoxia is sustained by decreased MO 2 min and anaerobic glycolysis • Cojinoba have adaptive responses that may facilitate survival during severe hypoxic events [ABSTRACT FROM AUTHOR]

Objective: To investigate the singleton, term gestation, and live birth rate per cycle initiated in our IVF program during a 1-year period. Design: Retrospective study of all first IVF cycles performed in the year 2002, with or without intracytoplasmic sperm injection (ICSI), with day 2/3 embryo transfer and using native or donated oocytes. Setting: Instituto Valenciano de Infetilidad (IVI), Valencia, Spain. Patient(s): Of 3,158 IVF cycles initially considered, 165 were excluded because of embryo freezing, follow-up loss, or embryo reduction. Of the remaining cycles, only 1,836 were first cycles with day 2/3 embryo transfer; of these, native oocytes were employed in 1,095 and donated oocytes in 741. Intervention(s): No patient underwent any additional procedure or intervention. Main Outcome Measure(s): The singleton, term gestation, and live birth rate per cycle initiated was used as a primary outcome measure. Results were analyzed according to the origin of the oocytes (native vs. donated) and the woman''s age (<37 and ?37 years old). Result(s): The ectopic pregnancy rate was higher in the native oocyte group. The singleton, term gestation, and live birth rate per cycle initiated was similar in native and donated oocyte groups (15.3% vs. 13.4%). In the native oocyte group, patients <37 years old showed a significantly better outcome. The singleton, term gestation, and live birth rate per cycle initiated was 16.7% and 10.8% in younger and older women, respectively. Conclusion(s): The singleton, term gestation, and live birth rate per cycle initiated constitutes an essential parameter for determining the real possibility of a healthy baby for a specific assisted reproduction technology (ART). [Copyright &y& Elsevier]

Peptide synthesis is an area with a wide field of application, from biomedicine to nanotechnology, that offers the option of simultaneously synthesizing a large number of sequences for the purpose of preliminary screening, which is a powerful tool. Nevertheless, standard protocols generate large volumes of solvent waste. Here, we present a protocol for the multiple Fmoc solid-phase peptide synthesis in tea bags, where reagent recycling steps are included. Fifty-two peptides with wide amino acid composition and seven to twenty amino acid residues in length were synthesized in less than three weeks. A clustering analysis was performed, grouping the peptides by physicochemical features. Although a relationship between the overall yield and the physicochemical features of the sequences was not established, the process showed good performance despite sequence diversity. The recycling system allowed to reduce N, N-dimethylformamide usage by 25–30% and reduce the deprotection reagent usage by 50%. This protocol has been optimized for the simultaneous synthesis of a large number of peptide sequences. Additionally, a reagent recycling system was included in the procedure, which turns the process into a framework of circular economy, without affecting the quality of the products obtained. [ABSTRACT FROM AUTHOR]

Aquaculture diversification is important for providing sustainable sources of food fish amidst changing environments, pathogens, economies, and market demand. Particularly for newly cultured species where information may be limited, optimization of culture practices relies on an understanding of the physiology and ecology of a species. The cojinoba (Seriolella violacea ; Centrolophidae), a coastal pelagic marine fish, is a species of growing importance for aquaculture production in South America. Although methods for breeding and larval to juvenile rearing have been established, little is known about the physiology of this species. Therefore, measures of metabolism, swimming capacity and efficiency, red:white (R:W) muscle ratios, and associated aerobic and anaerobic biochemical parameters, such as plasma glucose and lactate, and muscle enzyme activities (i.e., pyruvate kinase, citrate synthase, electron transport system [ETS]), were measured. For cojinoba at 15 °C with mean body length (BL; total length) of 22 cm, critical swimming velocity (U crit) was approximately 80 cm/s or 3.8 BL/s, and optimal swimming velocity (U opt) was 50 cm/s or 2.3 BL/s. Aerobic scope for metabolism was approximately 300 mg O 2 /kg/h, with Mo 2 max 3.4 fold greater than standard metabolic rate. Swimming was facilitated by linear increases in tail beat frequency until burst and glide swimming initiated near U crit. At low velocities, large (~20% BL) pectoral fins were used for propulsion and maneuverability/maintaining equilibrium; beat frequency diminished rapidly with increasing velocity. Red:white muscle ratios at 50% BL and 75% BL (caudal peduncle) were comparable to other ectothermic species, with a greater proportion of red muscle in the caudal peduncle presumably corresponding to facilitation of sustained pelagic swimming. Plasma glucose and lactate were elevated at U crit by 20% and 45% respectively, indicating mobilization of anaerobic energy sources at fatigue. Aerobic enzyme activities were much higher in red muscle, the ratio of anaerobic:aerobic enzyme activity was higher in white muscle, and ETS activities decreased at fatigue in both red and white muscle. The cojinoba has a moderate metabolic rate compared to other pelagic species, displays shoaling behavior, is maneuverable at low velocities due to pectoral fin use, but has optimal swimming efficiencies at higher velocities. These factors are beneficial for designing culture systems to promote exercise benefits for growth and welfare. • Swimming performance of Seriolella violacea was: U crit 80 cm/s, 3.8 BL/s at 15 °C. • Aerobic scope for metabolism was within the range of moderately active fishes. • Swimming efficiency (U opt) was greatest at mid-range of swimming capacity. • Metabolic enzymes activity differed by muscle type and ETS decreased at fatigue. • Red:white muscle ratios were greater in the caudal peduncle than mid-body region. [ABSTRACT FROM AUTHOR]