Search

An environmental enrichment protocol is essential for testing experimental models because it upholds animal welfare, aligns with ethical principles in animal experimentation, and reduces the number of animals needed. Calomys callosus , a South American rodent from the Cricetidae family, is bred in rodent animal facilities for its ease of handling, longevity, prolificacy, and effectively mimicking diseases like Toxoplasmosis, Leishmaniasis, Chagas, and Schistosomiasis. There are no reports on environmental enrichments for this species or their impact on reproductive parameters. This study aimed to analyze the influence of the Environmental Enrichment Program (EEP) on the reproductive and zootechnical performance of C. callosus kept in the Rodents Animal Facilities Complex of Universidade Federal de Uberlândia (UFU). Two experimental groups were established: with environmental enrichment EE+ and without environmental enrichment EE-. The materials used in the experimental design were changed weekly and alternated between dietary, occupational, physical/cognitive, and non-enrichment items. After the inclusion of the EEP, an improvement in the reproductive indices of C. callosus was identified in the EE+ group. These improvements included increased female precocity, a decreased interbirth interval, and a higher number of pairs producing more offspring. The postpartum zootechnical indices were also better, such as the number of animals born alive, improved weaning rates, and a reduced average number of deaths from birth to weaning. After the inclusion of the EEP, the general health status of C. callosus improved, reducing cases of non-infectious lumbar alopecia. Therefore, EEP allows C. callosus to express natural reproductive behaviors and improves parental care., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Klein, Soares de Assis, Pereira, Coutinho, Guerra, Neves, Ferreira, Lemos de Lima, Polveiro, Ferro and Vieira da Silva.)

The irreproducibility in scientific research has become a critical issue. Despite the essential role of rigorous methodology in constructing a scientific article, more than half of publications, on average, are considered non-reproducible. The implications of this irreproducibility extend to reliability problems, hindering progress in technological production and resulting in substantial financial losses. In the context of laboratory animal research, this work emphasizes the importance of choosing an appropriate experimental model within the 3R's principle (Refine, Reduce, Replace). This study specifically addresses a deficiency in data specification in scientific articles, revealing inadequacies in the description of crucial details, such as environmental conditions, diet, and experimental procedures. For this purpose, 124 articles from journals with relevant impact factors were analyzed, conducting a survey of data considered important for the reproducibility of studies. Important flaws in the presentation of data were identified in most of the articles evaluated. The results of this study highlight the need to improve the description of essential information, standardizing studies, and ensuring the reproducibility of experiments in areas such as metabolism, immunity, hormones, stress, among others, to enhance the reliability and reproduction of experimental results, aligning with international guidelines such as ARRIVE and PREPARE., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Neves, Klein, Silva, Bernardes, Malta, Vieira, Rosa, Lima, Ferreira and Silva.)

The murine model of experimental cerebral malaria (ECM) induced by Plasmodium berghei ANKA was used to investigate the relationship among pro-inflammatory cytokines, alterations in renal function biomarkers, and the induction of the TRAIL apoptosis pathway during malaria-associated acute kidney injury (AKI). Renal function was evaluated through the measurement of plasma creatinine and blood urea nitrogen (BUN). The mRNA expression of several cytokines and NaPi-IIa was quantified. Kidney sections were examined and cytokine levels were assessed using cytometric bead array (CBA) assays. The presence of glomerular IgG deposits and apoptosis-related proteins were investigated using in situ immunofluorescence assays and quantitative real-time PCR, respectively. NaPi-IIa downregulation in the kidneys provided novel insights into the pathogenesis of hypophosphatemia during CM. Histopathological analysis revealed characteristic features of severe malaria-associated nephritis, including glomerular collapse and tubular alterations. Pro-inflammatory cytokines, such as TNF-α, IL-1β, and IL-6, were upregulated. The TRAIL apoptosis pathway was significantly activated, implicating its role in renal apoptosis. The observed alterations in renal biomarkers and the downregulation of NaPi-IIa shed light on potential mechanisms contributing to renal dysfunction in ECM. The intricate balance between pro- and anti-inflammatory cytokines, along with the activation of the TRAIL apoptosis pathway, highlights the complexity of malaria-associated AKI and provides new therapeutic targets.

Climate change impact syntheses, such as those by the Intergovernmental Panel on Climate Change, consistently assert that limiting global warming to 1.5 °C is unlikely to safeguard most of the world's coral reefs. This prognosis is primarily based on a small subset of available models that apply similar 'excess heat' threshold methodologies. Our systematic review of 79 articles projecting coral reef responses to climate change revealed five main methods. 'Excess heat' models constituted one third (32%) of all studies but attracted a disproportionate share (68%) of citations in the field. Most methods relied on deterministic cause-and-effect rules rather than probabilistic relationships, impeding the field's ability to estimate uncertainty. To synthesize the available projections, we aimed to identify models with comparable outputs. However, divergent choices in model outputs and scenarios limited the analysis to a fraction of available studies. We found substantial discrepancies in the projected impacts, indicating that the subset of articles serving as a basis for climate change syntheses may project more severe consequences than other studies and methodologies. Drawing on insights from other fields, we propose methods to incorporate uncertainty into deterministic modeling approaches and propose a multi-model ensemble approach to generating probabilistic projections for coral reef futures., (© 2024. The Author(s).)

Annona muricata Linn. is a common plant found in the warmest regions of South and Central America and its use in traditional medicine has been reported for the treatment of various illnesses. In the current study, we investigate the antioxidant and anti-inflammatory activities of crude extract and fractions from A. muricata L. leaves in isolated murine phagocytic immune cells as well as experimental LPS-induced acute lung injury (ALI). In a luminol-dependent chemiluminescence assay, we showed that ethyl acetate (EtOAc.f) and n-butanol (BuOH.f) fractions-both rich in polyphenols-reduced the generation of reactive oxygen species (ROS) by neutrophils stimulated with opsonized zymosan; similar results were found in culture of bone marrow-derived macrophages (BMDMs). By evaluating anti-inflammatory activity in BMDMs, EtOAc.f and BuOH.f reduced secretion of IL-6 and expression of the co-stimulatory molecule CD40. Furthermore, in LPS-induced ALI, oral administration of EtOAc.f reduced myeloperoxidase (MPO) activity in lung tissue. In addition, on a mechanism dependent on glutathione levels, the oxidative damage was also attenuated. These findings revealed direct antioxidant and anti-inflammatory activities of polyphenols-rich fractions of A. muricata L. leaves on neutrophils and macrophages. Moreover, the reduced oxidative damage and levels of inflammatory markers in experimental ALI suggest that these fractions might be explored for the development of new therapies for inflammatory conditions.

Over this century, coral reefs will run the gauntlet of climate change, as marine heatwaves (MHWs) become more intense and frequent, and ocean acidification (OA) progresses. However, we still lack a quantitative assessment of how, and to what degree, OA will moderate the responses of corals to MHWs as they intensify throughout this century. Here, we first projected future MHW intensities for tropical regions under three future greenhouse gas emissions scenario (representative concentration pathways, RCP2.6, RCP4.5 and RCP8.5) for the near-term (2021-2040), mid-century (2041-2060) and late-century (2081-2100). We then combined these MHW intensity projections with a global data set of 1,788 experiments to assess coral attribute performance and survival under the three emissions scenarios for the near-term, mid-century and late-century in the presence and absence of OA. Although warming and OA had predominately additive impacts on the coral responses, the contribution of OA in affecting most coral attributes was minor relative to the dominant role of intensifying MHWs. However, the addition of OA led to greater decreases in photosynthesis and survival under intermediate and unrestricted emissions scenario for the mid- and late-century than if intensifying MHWs were considered as the only driver. These results show that role of OA in modulating coral responses to intensifying MHWs depended on the focal coral attribute and extremity of the scenario examined. Specifically, intensifying MHWs and OA will cause increasing instances of coral bleaching and substantial declines in coral productivity, calcification and survival within the next two decades under the low and intermediate emissions scenario. These projections suggest that corals must rapidly adapt or acclimatize to projected ocean conditions to persist, which is far more likely under a low emissions scenario and with increasing efforts to manage reefs to enhance resilience., (© 2021 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

The characterization, control, and reporting of environmental conditions in mammalian cell cultures is fundamental to ensure physiological relevance and reproducibility in basic and preclinical biomedical research. The potential issue of environment instability in routine cell cultures in affecting biomedical experiments was identified many decades ago. Despite existing evidence showing variable environmental conditions can affect a suite of cellular responses and key experimental readouts, the underreporting of critical parameters affecting cell culture environments in published experiments remains a serious problem. Here, we outline the main sources of potential problems, improved guidelines for reporting, and deliver recommendations to facilitate improved culture-system based research. Addressing the lack of attention paid to culture environments is critical to improve the reproducibility and translation of preclinical research, but constitutes only an initial step towards enhancing the relevance of in vitro cell cultures towards in vivo physiology., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Klein, Steckbauer, Alsolami, Arossa, Parry, Li and Duarte.)

Mammalian cell cultures are a keystone resource in biomedical research, but the results of published experiments often suffer from reproducibility challenges. This has led to a focus on the influence of cell culture conditions on cellular responses and reproducibility of experimental findings. Here, we perform frequent in situ monitoring of dissolved O 2 and CO 2 with optical sensor spots and contemporaneous evaluation of cell proliferation and medium pH in standard batch cultures of three widely used human somatic and pluripotent stem cell lines. We collate data from the literature to demonstrate that standard cell cultures consistently exhibit environmental instability, indicating that this may be a pervasive issue affecting experimental findings. Our results show that in vitro cell cultures consistently undergo large departures of environmental parameters during standard batch culture. These findings should catalyze further efforts to increase the relevance of experimental results to the in vivo physiology and enhance reproducibility., (© 2022. The Author(s).)

Our understanding of the response of reef-building corals to changes in their physical environment is largely based on laboratory experiments, analysis of long-term field data, and model projections. Experimental data provide unique insights into how organisms respond to variation of environmental drivers. However, an assessment of how well experimental conditions cover the breadth of environmental conditions and variability where corals live successfully is missing. Here, we compiled and analyzed a globally distributed dataset of in-situ seasonal and diurnal variability of key environmental drivers (temperature, pCO 2 , and O 2 ) critical for the growth and livelihood of reef-building corals. Using a meta-analysis approach, we compared the variability of environmental conditions assayed in coral experimental studies to current and projected conditions in their natural habitats. We found that annual temperature profiles projected for the end of the 21st century were characterized by distributional shifts in temperatures with warmer winters and longer warm periods in the summer, not just peak temperatures. Furthermore, short-term hourly fluctuations of temperature and pCO 2 may regularly expose corals to conditions beyond the projected average increases for the end of the 21st century. Coral reef sites varied in the degree of coupling between temperature, pCO 2 , and dissolved O 2 , which warrants site-specific, differentiated experimental approaches depending on the local hydrography and influence of biological processes on the carbonate system and O 2 availability. Our analysis highlights that a large portion of the natural environmental variability at short and long timescales is underexplored in experimental designs, which may provide a path to extend our understanding on the response of corals to global climate change., (© 2021 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

Coral reef research has predominantly focused on the effect of temperature on the breakdown of coral-dinoflagellate symbioses. However, less is known about how increasing temperature affects the establishment of new coral-dinoflagellate associations. Inter-partner specificity and environment-dependent colonization are two constraints proposed to limit the acquisition of more heat tolerant symbionts. Here, we investigated the symbiotic dynamics of various photosymbionts in different host genotypes under "optimal" and elevated temperature conditions. To do this, we inoculated symbiont-free polyps of the sea anemone Exaiptasia pallida originating from Hawaii (H2), North Carolina (CC7), and the Red Sea (RS) with the same mixture of native symbiont strains (Breviolum minutum, Symbiodinium linucheae, S. microadriaticum, and a Breviolum type from the Red Sea) at 25 and 32 °C, and assessed their ITS2 composition, colonization rates, and PSII photochemical efficiency (Fv/Fm). Symbiont communities across thermal conditions differed significantly for all hosts, suggesting that temperature rather than partner specificity had a stronger effect on symbiosis establishment. Overall, we detected higher abundances of more heat resistant Symbiodiniaceae types in the 32 °C treatments. Our data further showed that PSII photophysiology under elevated temperature improved with thermal pre-exposure (i.e., higher Fv/Fm), yet, this effect depended on host genotype and was influenced by active feeding as photochemical efficiency dropped in response to food deprivation. These findings highlight the role of temperature and partner fidelity in the establishment and performance of symbiosis and demonstrate the importance of heterotrophy for symbiotic cnidarians to endure and recover from stress.

Deoxygenation in coastal and open-ocean ecosystems rarely exists in isolation but occurs concomitantly with acidification. Here, we first combine meta-data of experimental assessments from across the globe to investigate the potential interactive impacts of deoxygenation and acidification on a broad range of marine taxa. We then characterize the differing degrees of deoxygenation and acidification tested in our dataset using a ratio between the partial pressure of oxygen and carbon dioxide (pO 2 /pCO 2 ) to assess how biological processes change under an extensive, yet diverse range of pO 2 and pCO 2 conditions. The dataset comprised 375 experimental comparisons and revealed predominantly additive but variable effects (91.7%, additive; 6.0%, synergistic; and 2.3%, antagonistic) of the dual stressors, yielding negative impacts across almost all responses examined. Our data indicate that the pO 2 /pCO 2 -ratio offers a simplified metric to characterize the extremity of the concurrent stressors and shows that more severe impacts occurred when ratios represented more extreme deoxygenation and acidification conditions. Importantly, our analysis highlights the need to assess the concurrent impacts of deoxygenation and acidification on marine taxa and that assessments considering the impact of O 2 depletion alone will likely underestimate the impacts of deoxygenation events and their ecosystem-wide consequences., (© 2020 John Wiley & Sons Ltd.)

Enhancing the resilience of corals to rising temperatures is now a matter of urgency, leading to growing efforts to explore the use of heat tolerant symbiont species to improve their thermal resilience. The notion that adaptive traits can be retained by transferring the symbionts alone, however, challenges the holobiont concept, a fundamental paradigm in coral research. Holobiont traits are products of a specific community (holobiont) and all its co-evolutionary and local adaptations, which might limit the retention or transference of holobiont traits by exchanging only one partner. Here we evaluate how interchanging partners affect the short- and long-term performance of holobionts under heat stress using clonal lineages of the cnidarian model system Aiptasia (host and Symbiodiniaceae strains) originating from distinct thermal environments. Our results show that holobionts from more thermally variable environments have higher plasticity to heat stress, but this resilience could not be transferred to other host genotypes through the exchange of symbionts. Importantly, our findings highlight the role of the host in determining holobiont productivity in response to thermal stress and indicate that local adaptations of holobionts will likely limit the efficacy of interchanging unfamiliar compartments to enhance thermal tolerance., (© 2020 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

Research efforts have intensified to foresee the prospects for marine biomes under climate change and anthropogenic drivers over varying temporal and spatial scales. Parallel with these efforts is the utilization of terminology, such as 'ocean acidification' (OA) and 'ocean deoxygenation' (OD), that can foster rapid comprehension of complex processes driving carbon dioxide (CO 2 ) and oxygen (O 2 ) concentrations in the global ocean and thus, are now widely used in discussions within and beyond academia. However, common usage of the terms 'acidification' and 'deoxygenation' alone are subjective and, without adequate contextualization, have the potential to mislead inferences over drivers that may ultimately shape the future state of marine ecosystems. Here we clarify the usage of the terms OA and OD as global, climate change-driven processes and discuss the various attributes of elevated CO 2 and reduced O 2 syndromes common to coastal ecosystems. We support the use of the existing terms 'coastal acidification' and 'coastal deoxygenation' because they help differentiate the sometimes rapid and extreme nature of CO 2 and O 2 syndromes in coastal ecosystems from the global, climate change-driven processes of OA and OD. Given the complexity and breadth of the processes involved in altering CO 2 and O 2 concentrations across marine ecosystems, we provide a workflow to enable contextualization and clarification of the usage of existing terms and highlight the close link between these two gases across spatial and temporal scales in the ocean. These distinctions are crucial to guide effective communication of research within the scientific community and guide policymakers responsible for intervening on the drivers to secure desirable future ocean states., (© 2019 John Wiley & Sons Ltd.)

Understanding the consequences of rising CO 2 and warming on marine ecosystems is a pressing issue in ecology. Manipulative experiments that assess responses of biota to future ocean warming and acidification conditions form a necessary basis for expectations on how marine taxa may respond. Although designing experiments in the context of local variability is most appropriate, local temperature and CO 2 characteristics are often unknown as such measures necessitate significant resources, and even less is known about local future scenarios. To help address these issues, we summarize current uncertainties in CO 2 emission trajectories and climate sensitivity, examine region-specific changes in the ocean, and present a straightforward global framework to guide experimental designs. We advocate for the inclusion of multiple plausible future scenarios of predicted levels of ocean warming and acidification in forthcoming experimental research. Growing a robust experimental base is crucial to understanding the prospect form and function of marine ecosystems in the Anthropocene., Competing Interests: Authors have no competing interests., (© 2020 The Authors.)

Respiratory sensitization as a consequence of exposure to chemical products has increased over the last decades, leading to an increase of morbidity. The increased use of synthetic compounds resulted in an exponential growth of substances to which we are potentially exposed on a daily basis. Some of them are known to induce respiratory sensitization, meaning that they can trigger the development of allergies. In the past, animal studies provided useful results for the understanding of mechanisms involved in the development of respiratory allergies. However, the mechanistic understanding of the involved cellular effects is still limited. Currently, no in vitro or in vivo models are validated to identify chemical respiratory sensitizers. Nonetheless, chemical respiratory sensitizers elicit a positive response in validated assays for skin sensitization. In this review, we will discuss how these assays could be used for respiratory sensitization and if necessary, what can be learnt from these assays to develop a model to assess the respiratory sensitizing potential of chemicals. In the last decades, much work has been done to study the respiratory toxicity of inhaled compounds especially in developing in vitro assays grown at the air-liquid interface. We will discuss how possibly the tests currently used to investigate general particle toxicity could be transformed to investigate respiratory sensitization. In the present review, we describe the most known mechanism involved in the sensitization process and the experimental in vivo and alternative in vitro models, which are currently available and how to adapt and improve existing models to study respiratory sensitization.

Anthropogenic nutrient inputs enhance microbial respiration within many coastal ecosystems, driving concurrent hypoxia and acidification. During photosynthesis, Symbiodinium spp., the microalgal endosymbionts of cnidarians and other marine phyla, produce O 2 and assimilate CO 2 and thus potentially mitigate the exposure of the host to these stresses. However, such a role for Symbiodinium remains untested for noncalcifying cnidarians. We therefore contrasted the fitness of symbiotic and aposymbiotic polyps of a model host jellyfish (Cassiopea sp.) under reduced O 2 (~2.09 mg/L) and pH (~ 7.63) scenarios in a full-factorial experiment. Host fitness was characterized as asexual reproduction and their ability to regulate internal pH and Symbiodinium performance characterized by maximum photochemical efficiency, chla content and cell density. Acidification alone resulted in 58% more asexual reproduction of symbiotic polyps than aposymbiotic polyps (and enhanced Symbiodinium cell density) suggesting Cassiopea sp. fitness was enhanced by CO 2 -stimulated Symbiodinium photosynthetic activity. Indeed, greater CO 2 drawdown (elevated pH) was observed within host tissues of symbiotic polyps under acidification regardless of O 2 conditions. Hypoxia alone produced 22% fewer polyps than ambient conditions regardless of acidification and symbiont status, suggesting Symbiodinium photosynthetic activity did not mitigate its effects. Combined hypoxia and acidification, however, produced similar numbers of symbiotic polyps compared with aposymbiotic kept under ambient conditions, demonstrating that the presence of Symbiodinium was key for mitigating the combined effects of hypoxia and acidification on asexual reproduction. We hypothesize that this mitigation occurred because of reduced photorespiration under elevated CO 2 conditions where increased net O 2 production ameliorates oxygen debt. We show that Symbiodinium play an important role in facilitating enhanced fitness of Cassiopea sp. polyps, and perhaps also other noncalcifying cnidarian hosts, to the ubiquitous effects of ocean acidification. Importantly we highlight that symbiotic, noncalcifying cnidarians may be particularly advantaged in productive coastal waters that are subject to simultaneous hypoxia and acidification., (© 2017 John Wiley & Sons Ltd.)

Background: During the last 250 years, the level of exposure to combustion-derived particles raised dramatically in western countries, leading to increased particle loads in the ambient air. Among the environmental particles, diesel exhaust particulate matter (DEPM) plays a special role because of its omnipresence and reported effects on human health. During recent years, a possible link between air pollution and the progression of atherosclerosis is recognized. A central effect of DEPM is their impact on the endothelium, especially of the alveolar barrier. In the present study, a complex 3D tetraculture model of the alveolar barrier was used in a dose-controlled exposure scenario with realistic doses of DEPM to study the response of endothelial cells., Results: Tetracultures were exposed to different doses of DEPM (SRM2975) at the air-liquid-interface. DEPM exposure did not lead to the mRNA expression of relevant markers for endothelial inflammation such as ICAM-1 or E-selectin. In addition, we observed neither a significant change in the expression levels of the genes relevant for antioxidant defense, such as HMOX1 or SOD1, nor the release of pro-inflammatory second messengers, such as IL-6 or IL-8. However, DEPM exposure led to strong nuclear translocation of the transcription factor Nrf2 and significantly altered expression of CYP1A1 mRNA in the endothelial cells of the tetraculture., Conclusion: In the present study, we demonstrated the use of a complex 3D tetraculture system together with a state-of-the-art aerosol exposure equipment to study the effects of in vivo relevant doses of DEPM on endothelial cells in vitro. To the best of our knowledge, this study is the first that focuses on indirect effects of DEPM on endothelial cells of the alveolar barrier in vitro. Exposure to DEPM led to significant activation and nuclear translocation of the transcription factor Nrf2 in endothelial cells. The considerably low doses of DEPM had a low but measurable effect, which is in line with recent data from in vivo studies.

Complex changes to UV radiation at the Earth's surface are occurring concurrently with ocean warming. Despite few empirical tests, jellyfish are hypothesised to be increasing in some parts of the world because they are robust to environmental stressors. Here we examine the effects of UV-B and ocean warming projections on zooxanthellate jellyfish polyps. We exposed Cassiopea sp. polyps to three levels of UV-B (future-low (1.43 Wm(2)), current (1.60 Wm(2)), future-high (1.77 Wm(2))) and two levels of temperature (current-day (25 °C) and future (28 °C)) over 6 weeks. The intensity of UV-B was varied throughout the day to mimic diel variation in UV-B irradiance. Polyp survival, asexual reproduction and YII were measured. In the current and future-high UV-B treatments, more polyps were produced in 25 °C than 28 °C. This pattern, however, was reversed under future-low UV-B conditions, where more polyps were produced at 28 °C. YII was highest under current summer conditions and future conditions of low UV-B and increased temperature. YII, however, was reduced under high UV-B conditions but was further reduced with warming. Our results suggest that although Cassiopea polyps may survive elevated UV-B and warming conditions, they are unlikely to thrive. If, however, UV-B radiation decreases then ocean warming may facilitate increases in Cassiopea populations.

Accurately predicting how marine biota are likely to respond to changing ocean conditions requires accurate simulation of interacting stressors, exposure regimes and recovery periods. Jellyfish populations have increased in some parts of the world and, despite few direct empirical tests, are hypothesised to be increasing because they are robust to a range of environmental stressors. Here, we investigated the effects of contaminated runoff on a zooxanthellate jellyfish by exposing juvenile Cassiopea sp. medusae to a photosystem II (PSII) herbicide, atrazine and reduced salinity conditions that occur following rainfall. Four levels of atrazine (0ngL(-1), 10ngL(-1), 2μgL(-1), 20μgL(-1)) and three levels of salinity (35 ppt, 25 ppt, 17 ppt) were varied, mimicking the timeline of light, moderate and heavy rainfall events. Normal conditions were then slowly re-established over four days to mimic the recovery of the ecosystem post-rain and the experiment continued for a further 7 days to observe potential recovery of the medusae. Pulse-amplitude modulated (PAM) chlorophyll fluorescence, growth and bell contraction rates of medusae were measured. Medusae exposed to the combination of high atrazine and lowest salinity died. After 3 days of exposure, bell contraction rates were reduced by 88% and medusae were 16% smaller in the lowest salinity treatments. By Day 5 of the experiment, all medusae that survived the initial pulse event began to recover quickly. Although atrazine decreased YII under normal salinity conditions, YII was further reduced when medusae were exposed to both low salinity and atrazine simultaneously. Atrazine breakdown products were more concentrated in jellyfish tissues than atrazine at the end of the experiment, suggesting that although bioaccumulation occurred, atrazine was metabolised. Our results suggest that reduced salinity may increase the susceptibility of medusae to herbicide exposure during heavy rainfall events., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

We developed a coculture model of the lung–blood barrier using human bronchial epithelial cells(16HBE14o-), monocytes (THP-1) and human lung microvascular endothelial cells (HLMVEC) in which several parameters can be assessed simultaneously. The epithelial and endothelial cells were grown on opposite sides of a microporous membrane. Electron and confocal microscopic pictures show the presence of the cells in their appropriate compartment and both cell types do not show evidence of growing through the pores. Out of three endothelial cell types (EAhy.926, HUVEC and HLMVEC), the last was chosen as the most appropriate cell type, best resembling the pulmonary endothelium and allowing the expression of functional tight junctions in the 16HBE14o- monolayer with sufficiently high transepithelial electrical resistance (TEER) values. Finally, monocytes were added to the apical compartment. PMA-activated macrophages significantly affected barrier integrity (73% TEER reduction compared to control after 24 h) and disrupted the epithelial tight junctions as shown by redistribution of ZO-1 labeling. Alternatively, monocytes could be activated using lipopolysaccharide, at a sub-toxic level int he apical compartment and only induced a small, though significant, reduction in TEER.This coculture system is a representative model of the lung–blood barrier with barrier integrity as the main toxicity endpoint.

Across different species, cellular efflux pumps such as P-glycoprotein (P-gp; also termed multidrug resistance protein 1 [MDR1]) serve as a first line of defense by transporting toxic xenobiotics out of the cell. This mechanism is also active in aquatic organisms such as mussels, fish, and their larvae. Modulation of this resistance mechanism by chemical agents occurring in the environment could result in either higher or lower internal concentrations of toxic or endogenous compounds in cells. The aim of the present study was to explore and quantify the inhibition of the P-gp efflux pumps by several ubiquitous aquatic contaminants. The calcein-acetoxymethyl ester (calcein-AM) assay commonly used in pharmacological research was established with P-gp-overexpressing Madin-Darby canine kidney cells (MDCKII-MDR1) in a 96-well plate, avoiding extra washing, centrifugation, and lysis steps. This calcein-AM-based P-gp cellular efflux pump inhibition assay (CEPIA) was used to study the inhibition by commonly occurring environmental contaminants. Among others, the compounds pentachlorophenol, perfluorooctane sulfonate, and perfluorooctanoate strongly inhibited the P-gp-mediated efflux of calcein-AM while the chloninated alkanes did not seem to interact with the transporter. The fact that common pollutants can be potent modulators of the efflux transporters is a motive to further study whether this increases the toxicity of other contaminants present in the same matrices., (© 2013 SETAC.)

Increasing ocean temperatures and strengthening boundary currents have caused the poleward migration of many marine species. Cubozoan jellyfish known to cause Irukandji syndrome have historically been confined to tropical waters but may be expanding into subtropical regions. Here, we examine the interactive effects of warming and acidification on the population dynamics of polyps of an Irukandji jellyfish, Alatina nr mordens, and the formation of statoliths in newly metamorphosed medusae, to determine if this jellyfish could tolerate future conditions predicted for southeast Queensland (SEQ), Australia. Two experiments, examining the orthogonal factors of temperature and pH, were undertaken. Experiment 1 mimicked the current, ca. 2050 and ca. 2100 summer temperature and pH conditions predicted for SEQ using A1F1 scenarios (temperature: 25, 27, 29 °C; pH: 7.9, 7.8, 7.6) and Experiment 2 mimicked current and future winter conditions (18 and 22 °C, pH 7.9, 7.8, 7.6). All polyps in Experiment 1 survived and budded. Fewer polyps budded in the lower pH treatments; however, patterns varied slightly among temperature treatments. Statoliths at pH 7.6 were 24% narrower than those at pH 7.8 and 7.9. Most polyps survived the winter conditions mimicked by Experiment 2 but only polyps in the 22 °C, pH 7.9 treatment increased significantly. The current absence of A. nr mordens medusae in SEQ, despite the polyps' ability to tolerate the current temperature and pH conditions, suggests that ecological, rather than abiotic factors currently limit their distribution. Observations that budding was lower under low pH treatments suggest that rates of asexual reproduction will likely be much slower in the future. We consider that A. nr mordens polyps are likely to tolerate future conditions but are unlikely to thrive in the long term. However, if polyps can overcome potential ecological boundaries and acidification proceeds slowly A. nr mordens could expand polewards in the short term., (© 2013 John Wiley & Sons Ltd.)

Background: Exposure to fine and ultra-fine ambient particles is still a problem of concern in many industrialised parts of the world and the intensified use of nanotechnology may further increase exposure to small particles. Complex in vitro coculture systems may be valuable tools to study particle-induced processes and to extrapolate effects of particles on the lung. A system consisting of four different human cell lines which mimics the cell response of the alveolar surface in vitro was developed to study native aerosol exposure (Vitrocell™ chamber). The system is composed of an alveolar type-II cell line (A549), differentiated macrophage-like cells (THP-1), mast cells (HMC-1) and endothelial cells (EA.hy 926), seeded in a 3D-orientation on a microporous membrane., Results: The spatial distribution of the cells in the tetraculture was analysed by confocal laser scanning microscopy (CLSM), showing a confluent layer of endothelial and epithelial cells on both sides of the transwell. Macrophage-like cells and mast cells can be found on top of the epithelial cells. The cells formed colonies under submerged conditions, which disappeared at the ALI. To evaluate the response to oxidative stress, the dichlorodihydrofluorescein diacetate (DCFH-DA) assay was used together with 2,2'-azobis-2-methyl-propanimidamide-dihydrochloride (AAPH) as inducer of oxidative stress. The tetraculture showed less induction of reactive oxygen species (ROS) production after being treated with a positive control compared to the monocultures of EA.hy 926, THP-1 and HMC-1. Submerged cultures showed elevated ROS and IL-8 levels compared to ALI cultures. The Vitrocell™ aerosol exposure system was not significantly influencing the viability. Using this system, cells were exposed to an aerosol of 50 nm SiO2-Rhodamine NPs in PBS. The distribution of the NPs in the tetraculture after exposure was evaluated by CLSM. Fluorescence from internalized particles was detected in CD11b-positive THP-1 cells only., Conclusion: The system can be used in conjunction with a native aerosol exposure system and may finally lead to a more realistic judgement regarding the hazard of new compounds and/or new nano-scaled materials in the future. The results for the ROS production and IL-8 secretion suggest that submerged exposure may lead to an overestimation of observed effects.

Exposure to particulate matter (PM) like nanoparticles (NPs) has increased in the last century due to increased combustion processes, road traffic, etc. In addition, the progress in chemical and cosmetic industry led to many new compounds, e.g. fragrances, which humans are exposed to every day. Many chemicals are known to act as contact and some as respiratory sensitizers, causing allergic reactions. Exposure to small particles of less than 100 nm in diameter is linked with an increased risk of respiratory diseases, such as asthma or rhinitis. To date already more than 1000 customer products contain eNPs without knowing much about the health effects. In comparison to chemicals, the mechanisms by which PM and eNPs can cause sensitization are still not fully understood. Validated and regulatory accepted in vitro models to assess this hazard in its full range are still missing. While a huge number of animal studies contributed to our knowledge about sensitization processes, knowledge on involved cellular mechanisms is still limited. In this review relevant in vitro models to study and elucidate these mechanisms in more detail are presented and their potential to serve as part of a tiered testing strategy is discussed., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Rationale and Objectives: Radiology residents must now participate in a learning activity that involves identification and analysis of system errors and implementation of potential solutions. Evidence of participation must be documented in the resident's learning portfolio., Materials and Methods: An activity based on adult learning principles was designed for residents to increase their knowledge of health care systems and problems; gain experience in writing a proposal, conducting an investigation, and reporting results; organize and present information in a supportive environment; and document participation in their portfolio. Postgraduate year 2 residents identify a systems problem. A written proposal is required and must include a "plan" that includes a hypothesis, a methods section that explains what they will "do" as an intervention, a "study" that involves collection and analysis of relevant data, and a systems change or "act." Proposals approved by the program director are presented to the radiology department. Residents complete projects, evaluate their effectiveness, and present their results by spring of postgraduate year 3., Results: Goals, objectives, and guidelines were written. Assessment tools were identified. From 2006 to 2008, nine projects were proposed and conducted by 12 residents. Local and national systems issues were selected, and interventions involved residents, faculty, and medical students. A timeline was imposed to promote sustained effort., Conclusion: Opportunities of daily work can be used to teach and learn systems-based practice concepts. Residents can use the scientific method to test effects of change on health care systems. Relevant and practical projects enable residents to learn while improving their clinical and learning environments.

Rationale and Objectives: The residency review committee (RRC) for diagnostic radiology of the Accreditation Council for Graduate Medical Education mandates core competencies including computer-aided applications in medicine. The purpose of this review was to evaluate the use of RadioGraphics' on-line CME to satisfy the RRC requirements., Materials and Methods: Twenty radiology residents at a university training program read the same four articles in the on-line version of RadioGraphics. Before reading each article, the residents took the associated CME pre-test and, after completing the article, the CME post-test. Each resident completed a survey to evaluate the quality of the resident experience using RadioGraphics' CME on-line program after completing the four articles and tests., Results: The combined mean scores of all four articles pre-test and post-test scores were 5.6 and 9.3. Significant improvement in the test scores was determined by a student t-test (P < .001). Fourteen residents agreed and one resident disagreed with the statement that the modules were time effective. Nineteen of 20 residents agreed with the statement that valuable information for future practice was gained and that they would continue to use RadioGraphics for CME in the future. All of the residents agreed with the statement that the experience satisfied the residency's requirement to teach computer skills appropriate for ongoing learning., Conclusion: RadioGraphics' on-line CME an effective method to teach residents skills required by the RRC.