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Background: Training is required to achieve proficiency in airway management. Simulators are of utmost importance not only for the purpose of training novices, but also for evaluating newer airway devices and techniques. Growing evidence supports inadequate anatomic airway reproduction in adult and pediatric manikins. Methods: We conducted an observational study comparing 17 radiological anatomic airway measurements obtained via the computed tomography of three commercially available manikins with the same measurements obtained from a population of newborns/infant (range: 0–3 months) undergoing magnetic resonance imaging for diagnostic purposes. According to the reference (mean and standard deviation (SD) of the pediatric population), each manikin measurement was defined as adequate, partially adequate or inadequate (difference between means: ≤±1, 1.0–1.96 or >1.96 SD, respectively). The primary outcome was the number of measurements with an adequate reproduction of airways. Results: We included 27 pediatric patients (21 ± 19 days, 48% males, 46.6 ± 3.5 cm, 2.7 ± 0.5 Kg and 12.6 ± 2.9 kg/m2). All manikins had n = 11/17 measurements with inadequate airway anatomic reproduction. The three measurements with more adequate reproduction were the height of the soft palate, retropalatal airspace volume and tongue volume (adequate in two manikins, and partially adequate in the remaining one). Conclusions: In three manikins commonly used for training in pediatric airways, static dimensions do not seem anatomically correct in relation to those of pediatric patients. Such inaccuracies may introduce biases in airway device development as well as in training.

Many studies report negative associations between exposure to large concentrations of contaminants and life-history traits of animals. As a consequence, they argue to derive linear models that can be applied to predict effects in sub-threshold or lowdose exposure scenarios. However, several recent studies found that exposure to low doses of a contaminant may induce a hormetic response, i.e. stimulatory or beneficial effects at low concentrations, but harmful effects at higher concentrations. Hormesis might be a novel fundamental pillar in the field of ecotoxicology, as it may promote the evolution of adaptive coping mechanisms in rapidly changing and challenging environments. However, because hormesis occurs in the lowdose zone of the dose-response, it has been often neglected. In this review, we have discussed how low-dose contaminant exposure may adaptively modify molecular and physiological mechanisms that may lead to organisms better capable of coping with challenging environments, how such responses may be transgenerational, and how thus this issue can no longer be ignored in ecotoxicological studies. In so doing, we have also identified some of the main limitations of ecotoxicological studies that, by masking potential hormetic responses of animals to chemicals, make the integration of hormesis complicated to achieve.

Tropical forest degradation affects host-parasite interactions, determining the probability of animals acquiring an infection. The activation of an immune response to fight off infections requires energy and other resources such as antioxidants which may be redirected from growth and reproduction. A key question is how selective logging—the most common form of tropical forest degradation—impacts the prevalence of avian haemosporidian infection and its correlated physiological responses (nutritional and oxidative status markers). We investigated the prevalence of Plasmodium, Haemoproteus, and Leucocytozoon parasites in 14 understorey bird species in lowland, logged and unlogged, old-growth forests of Borneo. Prevalences of infections were similar between selectively logged and unlogged forests. To explore nutritional and oxidative status effects of haemosporidian infections, we examined associations between infections and plasma proteins, plasma triglycerides, and multiple blood-based markers of oxidative status, testing for an impact of selective logging on those markers. Birds infected with Plasmodium showed higher levels of plasma proteins and non-enzymatic antioxidant capacity, and lower levels of plasma triglycerides and glutathione, compared with haemosporidian-free individuals. Conversely, birds infected with Haemoproteus showed no changes in nutritional or physiological markers compared with uninfected individuals. These results indicate higher metabolic and physiological costs of controlling Plasmodium infection, compared with Haemoproteus, possibly due to higher pathogenicity of Plasmodium. Selectively logged forests had no effect on the responses of birds to infection, suggesting that the environmental conditions of degraded forests do not appear to induce any appreciable physiological demands in parasitised birds.

Species persistence in the Anthropocene is dramatically threatened by global climate change. Large emissions of carbon dioxide (CO2) from human activities are driving increases in mean temperature, intensity of heatwaves, and acidification of oceans and freshwater bodies. Ectotherms are particularly sensitive to CO2-induced stressors, because the rate of their metabolic reactions, as well as their immunological performance, are affected by environmental temperatures and water pH. We reviewed and performed a meta-analysis of 56 studies, involving 1259 effect sizes, that compared oxidative status or immune function metrics between 42 species of ectothermic vertebrates exposed to long-term increased temperatures or water acidification (≥48 h), and those exposed to control parameters resembling natural conditions. We found that CO2-induced stressors enhance levels of molecular oxidative damages in ectotherms, while the activity of antioxidant enzymes was upregulated only at higher temperatures, possibly due to an increased rate of biochemical reactions dependent on the higher ambient temperature. Differently, both temperature and water acidification showed weak impacts on immune function, indicating different direction (increase or decrease) of responses among immune traits. Further, we found that the intensity of temperature treatments (Δ°C) and their duration, enhance the physiological response of ectotherms, pointing to stronger effects of prolonged extreme warming events (i.e., heatwaves) on the oxidative status. Finally, adult individuals showed weaker antioxidant enzymatic responses to an increase in water temperature compared to early life stages, suggesting lower acclimation capacity. Antarctic species showed weaker antioxidant response compared to temperate and tropical species, but level of uncertainty in the antioxidant enzymatic response of Antarctic species was high, thus pairwise comparisons were statistically non-significant. Overall, the results of this meta-analysis indicate that the regulation of oxidative status might be one key mechanism underlying thermal plasticity in aquatic ectothermic vertebrates.

Selective logging is a major driver of environmental changes in the tropics. Recently, there has been increasing interest in understanding which traits make bird species resilient or vulnerable to such changes. Physiological stress mediated by the steroid hormone corticosterone (CORT) might underlie changes in local abundance of species because it regulates a range of body functions and behaviours to maintain homeostasis in changing environments. We conducted a 3-year study to assess (a) the variation in CORT levels in feathers (where CORT is deposited during the moult) of 10 understorey bird species across both unlogged old-growth forest and selectively logged forest in Borneo, (b) how this variation is associated with within-year variation in population abundance between forest types and (c) whether the difference in feather CORT (fCORT) between co-specific populations living in unlogged and logged forests in 1 year is related with their difference in population abundance the following year. We used effect size estimates to measure standardized magnitude and direction of fCORT changes between unlogged and selectively logged forest. We found small to large effect sizes, indicating large among-species variation in physiological acclimatization to changes in forest conditions. In 2016 and 2018, species with relatively higher fCORT in unlogged forest were relatively more abundant in logged forest in the same year; in 2017, species with relatively higher fCORT in logged forest were relatively more abundant in logged forest. Importantly, we found that for a given species, the difference in fCORT at year (x) between unlogged and logged forests was negatively related with a difference in its local abundance between the two forest types in the following year (x + 1). Our results point to glucocorticoid hormones as potential mediators of carry-over effects on population abundance due to direct and indirect effects of silvicultural practices in tropical forests of Borneo, suggesting fCORT as a potential marker of population changes. A free Plain Language Summary can be found within the Supporting Information of this article.

Background The coronavirus disease 2019 (COVID-19) pandemic has caused over 530 million infections to date (June 2022), with a high percentage of intensive care unit (ICU) admissions. In this context, relatives have been restricted from visiting their loved ones admitted to hospital. This situation has led to an inevitable separation between patients and their families. Video communication could reduce the negative effects of such phenomenon, but the impact of this strategy on levels of anxiety, depression, and PTSD disorder in caregivers is not well-known. Methods We conducted a prospective study (6 October 2020–18 February 2022) at the Policlinico University Hospital in Catania, including caregivers of both COVID-19 and non-COVID-19 ICU patients admitted during the second wave of the pandemic. Video-calls were implemented twice a week. Assessment of anxiety, depression, and PTSD was performed at 1-week distance (before the first, T1, and before the third, video-call, T2) using the following validated questionnaires: Impact of Event Scale (Revised IES-R), Center for Epidemiologic Studies Depression Scale (CES-D), and Hospital Anxiety and Depression Scale (HADS). Results Twenty caregivers of 17 patients completed the study (T1 + T2). Eleven patients survived (n = 9/11 in the COVID-19 and n = 2/6 in the “non-COVID” group). The average results of the questionnaires completed by caregivers between T1 and T2 showed no significant difference in terms of CES-D (T1 = 19.6 ± 10, T2 = 22 ± 9.6; p = 0.17), HADS depression (T1 = 9.5 ± 1.6, T2 = 9 ± 3.9; p = 0.59), HADS anxiety (T1 = 8.7 ± 2.4, T2 = 8.4 ± 3.8; p = 0.67), and IES-R (T1 = 20.9 ± 10.8, T2 = 23.1 ± 12; p = 0.19). Similar nonsignificant results were observed in the two subgroups of caregivers (COVID-19 and “non-COVID”). However, at T1 and T2, caregivers of “non-COVID” patients had higher scores of CES-D (p = 0.01 and p = 0.04, respectively) and IES-R (p = 0.049 and p = 0.02, respectively), while HADS depression was higher only at T2 (p = 0.02). At T1, caregivers of non-survivors had higher scores of CES-D (27.6 ± 10.6 vs 15.3 ± 6.7, p = 0.005) and IES-R (27.7 ± 10.0 vs 17.2 ± 9.6, p = 0.03). We also found a significant increase in CES-D at T2 in ICU-survivors (p = 0.04). Conclusions Our preliminary results showed that a video-call implementation strategy between caregivers and patients admitted to the ICU is feasible. However, this strategy did not show an improvement in terms of the risk of depression, anxiety, and PTSD among caregivers. Our pilot study remains exploratory and limited to a small sample.

Melatonin modulates the circadian rhythm and has been studied as a preventive measure against the development of delirium in hospitalized patients. Such an effect may be more evident in patients admitted to the ICU, but findings from the literature are conflicting. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs). We assessed whether melatonin or ramelteon (melatonin agonist) reduce delirium incidence as compared to a placebo in ICU patients. Secondary outcomes were ICU length of stay, duration of mechanical ventilation (MV) and mortality. Estimates are presented as risk ratio (RR) or mean differences (MD) with 95% confidence interval (CI). Nine RCTs were included, six of them reporting delirium incidence. Neither melatonin nor ramelteon reduced delirium incidence (RR 0.76 (0.54, 1.07), p = 0.12; I2 = 64%), although a sensitivity analysis conducted adding other four studies showed a reduction in the risk of delirium (RR = 0.67 (95%CI 0.48, 0.92), p = 0.01; I2 = 67). Among the secondary outcomes, we found a trend towards a reduction in the duration of MV (MD −2.80 (−6.06, 0.47), p = 0.09; I2 = 94%) but no differences in ICU-LOS (MD −0.26 (95%CI −0.89, 0.37), p = 0.42; I2 = 75%) and mortality (RR = 0.85 (95%CI 0.63, 1.15), p = 0.30; I2 = 0%). Melatonin and ramelteon do not seem to reduce delirium incidence in ICU patients but evidence is weak. More studies are needed to confirm this finding.

Selective logging is the main anthropogenic disturbance in tropical forests, driving shifts in species abundances. Body size and body condition are important metrics of fitness that may be affected by habitat degradation. We conducted a four-year study to investigate how selective logging impacted the body size and body condition index (BCI) of 55 Bornean bird species and whether changes in body metrics were associated with shifts in relative population abundance. Frugivorous and omnivorous birds had reduced body size in selectively logged versus unlogged forest, but we found no evidence for selective removal of individuals driven by sex differences or post-fledging body size, indicating different developmental conditions for frugivores and omnivores in logged forest. Change in body size between forest types showed no clear patterns for insectivorous birds, and did not differ between IUCN categories. BCI of birds was affected by study year, suggesting an effect of climatic conditions on food availability, but not by logging. At the community level, post-logging change in population abundance was not associated with reduced body size, although between species variation suggests that adverse environmental conditions and different coping strategies underlie body size reductions in logged forest. Our study suggests that body size is a valuable metric to assess how logging impacts forest birds, pointing towards potential functional consequences related to seed dispersal within logged forests and need for improved silvicultural practices.

Widespread selective logging in tropical forest causes structural damage and associated shifts in species composition, but we lack understanding of how selective logging impacts mechanistic processes that drive these biodiversity changes. Movement is a vital mechanistic process underpinning demographic, ecological, and evolutionary processes that likely determine species responses to logging. We assessed how tropical selective logging impacts local movements of 71 understory avian species in Sabah, Malaysian Borneo, and determined whether movement patterns relate to species' conservation status, functional traits, sensitivity to logging and trophic position. We used a capture-mark-recapture methodology and a hierarchical Bayesian framework to model maximum observed local movement distances, accounting for spatial sampling heterogeneity. Across the avian community, we found a higher probability of moving shorter distances (up to 200 m) in logged forests, and higher movement probability at longer distances (above 200 m) in unlogged forests. Altered movement patterns after logging may reflect increased understory density, changed resource distribution and/or predation risks, and suggest smaller home-range sizes. Species' conservation status, body mass, foraging guild, logging sensitivity and trophic position were unrelated to the magnitude of movement change. The continued persistence of understory species in our sample after selective logging may depend on flexibility in movement behaviour, conferring resilience to habitat degradation and the retention of high conservation values. This lends further support for the protection of these logged forests for biodiversity conservation.

Kyle et al. [...]

The human body is inhabited by around 1013 microbes composing a multicomplex system, termed microbiota, which is strongly involved in the regulation and maintenance of homeostasis. Perturbations in microbiota composition can lead to dysbiosis, which has been associated with several human pathologies. The gold-standard method to explore microbial composition is next-generation sequencing, which involves the analysis of 16S rRNA, an indicator of the presence of specific microorganisms and the principal tool used in bacterial taxonomic classification. Indeed, the development of 16S RNA sequencing allows us to explore microbial composition in several environments and human body districts and fluids, since it has been detected in “germ-free” environments such as blood, plasma, and urine of diseased and healthy subjects. Recently, prokaryotes showed to generate extracellular vesicles, which are known to be responsible for shuttling different intracellular components such as proteins and nucleic acids (including 16S molecules) by protecting their cargo from degradation. These vesicles can be found in several human biofluids and can be exploited as tools for bacterial detection and identification. In this review, we examine the complex link between circulating 16S RNA molecules and bacteria-derived vesicles.

Neurosteroids can modulate I³-aminobutyric acid type A receptor-mediated inhibitory currents. Recently, we discovered that the neurosteroids progesterone, 5α-dihydroprogesterone, allopregnanolone, and pregnanolone are reduced in the cerebrospinal fluid of patients with status epilepticus (SE). However, it is undetermined whether neurosteroids influence SE. For this reason, first we evaluated whether the inhibitor of adrenocortical steroid production trilostane (50 mg/kg) could modify the levels of neurosteroids in the hippocampus and neocortex, and we found a remarkable increase in pregnenolone, progesterone, 5α-dihydroprogesterone, and allopregnanolone levels using liquid chromatography tandem mass spectrometry. Second, we characterized the dynamics of SE in the presence of the varied neurosteroidal milieu by a single intraperitoneal kainic acid (KA; 15 mg/kg) injection in trilostane-treated rats and their controls. Convulsions started in advance in the trilostane group, already appearing 90 minutes after the KA injection. In contrast to controls, convulsions prevalently developed as generalized seizures with loss of posture in the trilostane group. However, this effect was transient, and convulsions waned 2 hours before the control group. Moreover, electrocorticographic traces of convulsions were shorter in trilostane-treated rats, especially at the 180-minute (P

Dramatic changes in species composition have been found following selective logging and forest fragmentation. The different responses of bird species to these disturbances suggest that some species are more sensitive to environmental changes than others. Recent studies have suggested that the chances of species to adapt to new environments may be mediated by their stress physiology and immunity. We reviewed and performed a meta-analysis of studies that compared physiological and immunological endpoints of bird and mammal species between degraded (logged and fragmented) forests and undisturbed forests. We found that stress hormones and immunity markers show consistent changes in response to habitat degradation in birds and mammals. Higher physiological and immunological responses were found in those animals living in forests that were subjected to clear-cutting. Furthermore, we found that birds and species belonging to IUCN ‘Threatened’ categories exhibited significantly larger effect size estimates than mammals and ‘Least Concern’ species, respectively. Our meta-analysis revealed that changes in the production of stress hormones and in some immune traits are a significant consequence of forest disturbance. Physiology and immunity might be two important mediators of the adaptiveness of a given species to changing forests.

Selective logging is the dominant form of human disturbance in tropical forests, driving changes in the abundance of vertebrate and invertebrate populations relative to undisturbed old‐growth forests. A key unresolved question is understanding which physiological mechanisms underlie different responses of species and functional groups to selective logging. Regulation of oxidative status is thought to be one major physiological mechanism underlying the capability of species to cope with environmental changes. Using a correlational cross‐sectional approach, we compared a number of oxidative status markers among 15 understorey bird species in unlogged and selectively logged forest in Borneo in relation to their feeding guild. We then tested how variation of markers between forest types was associated with that in population abundance. Birds living in logged forests had a higher activity of the antioxidant enzyme superoxide dismutase and a different regulation of the glutathione cycle compared to conspecific birds in unlogged forest. However, neither oxidative damage nor oxidized glutathione differed between forest types. We also found that omnivores and insectivores differed significantly in all markers related to the key cellular antioxidant glutathione irrespective of the forest type. Species with higher levels of certain antioxidant markers in a given type of forest were less abundant in that forest type compared to the other. Our results suggest that there was little long‐term effect of logging (last logging rotation occurred ~15 years prior to the study) on the oxidative status of understorey bird species. However, it is unclear if this was owing to plasticity or evolutionary change. Our correlative results also point to a potential negative association between some antioxidants and population abundance irrespective of the forest type.

International audience; 1. Diet quality may have an important effect on the regulation of oxidative statusand the immune system during an infectious disease. However, the relationshipamong intake of specific dietary molecules, an individual’s oxidative status and theoccurrence and progress of a viral disease remains almost unexplored in free‐livingorganisms.2. Here, we study a wild, long‐lived animal, the Magnificent frigatebird Fregata magnificensto investigate: (a) the differences in a number of physiological traits (biomarkersof blood oxidative status, corticosterone (CORT), immunity andinflammation) between sick and healthy nestlings; and (b) whether experimentallyincreased intake of resveratrol (a polyphenol with antioxidant and antiviral properties)affects these physiological markers during the progress of a severe viraldisease.3. Birds with visible clinical signs showed higher oxidative damage, haemolysis andhaemagglutination scores and lower antioxidant defences in comparison withbirds without clinical signs. At the end of the experiment, supplemented birdsshowed the following: (a) increased plasma haptoglobin levels and circulating antioxidantdefences; (b) reduced generation of lipid oxidative damage; and (c) negligibleto no influence on immune markers, baseline CORT levels and activity ofantioxidant enzymes.4. Our work illustrates how the availability of specific organic molecules in the dietmay constrain the individuals’ capacity to cope with viral infections in free‐livinganimals

In countries with emerging and developing economies the need to promote development and the lack of information on the status of the Near Threatened Eurasian otter Lutra lutra have given rise for concern about the conservation status of the species. In Albania information about the distribution of this otter dates from 1985. In 2013 we resurveyed 31 sites previously surveyed in 1985, and a further 42 sites throughout the country. At each site nine habitat variables of potential importance to otters were recorded and analysed. Overall the distribution pattern in 2013 did not differ from that recorded in 1985, although a reduction in marking intensity suggested a possible decline in otter numbers. Distribution of the otter has been influenced by land use and human density, suggesting man-induced habitat changes since the fall of communism may have affected the quality and fragmentation of otter habitats.

Summary 1.There is substantial interest of evolutionary ecologists in the proximate mechanisms that modulate vocal communication. In recent times, there has been growing interest in the role of oxidative stress as a mediator of avian song expression. 2.Here we tested whether the experimental inhibition of the synthesis of a key cellular antioxidant (glutathione) reduces song rate metrics of male European starlings (Sturnus vulgaris). We measured the effect of our treatment on total song rate and on its two components, undirected and nest-box oriented song, outside the breeding season. 3.Treated males that did not own a nest-box (subordinate males likely to be of lower quality) suffered increased oxidative stress relative to untreated males, while treated males that owned a nest-box (dominant males likely to be of higher quality) did not. Treated non-owners also reduced their undirected song rate, whereas treated nest-box owners did not suffer any reduction in song rate. 4.Our results revealed that inhibition of a key cellular antioxidant results in decreased vocal communication in a social vertebrate, and that this effect is dependent on its social status (nest-box owner versus non-owner). 5.This work provides support for the hypothesis that acoustic signals may honestly convey information about the individual oxidative status and capacity to regulate the oxidative balance. Our findings raise the possibility of hitherto unexplored impacts of oxidative stress on fitness traits in social species. This article is protected by copyright. All rights reserved.

Land-use changes are one main cause of biodiversity loss. Selective logging is the most common technique of timber extraction applied to tropical forests, driving species loss and population abundance changes. One main question to understand species’ responses to selective logging is which proximate mechanisms underlie species abundance changes. In this Ph.D. project I have used a cross-sectional approach to investigate the effects of selective logging on the stress physiology of understorey birds, and correlative analyses to investigate the effects of physiological changes on population abundance, across unlogged and selectively logged forest of Borneo. The first goal of the project was to determine which physiological endpoints of vertebrates are affected by forest disturbance. To this end, I reviewed all available literature and used meta-analytical techniques to quantify the size of the effects of different forest disturbances, including selective logging, on physiological and immunological parameters. ​ ​ I have then investigated the effect of selective logging on the activity of the hypothalamic-pituitary-adrenal (HPA) axis in 10 understorey bird species. I used as marker of HPA axis activity the concentrations of corticosterone, the avian glucocorticoid hormone, deposited in feathers. Another important physiological mechanism for maintaining homeostasis is the regulation of cellular oxidative status. Thus, I measured eight different markers of oxidative status in 15 understorey bird species living either in unlogged and selectively logged forests. I also investigated differences in the oxidative status between feeding guilds (i.e. insectivores and omnivores) and how they are affected by selective logging. ​ ​ Last, I tested for differences in body size and body condition of more than 50 bird species across unlogged and selectively logged forests. Changes in body size and body condition can be sub-lethal effects of habitat degradation that may act as early signals to predict future population responses. This hypothesis was tested correlating changes in body size and body condition with changes in population abundance between the two types of forest. Results point to feather corticosterone as a promising tool for monitoring the impacts of sylvicultural practises on understorey birds. There is little long-term effect of logging on the oxidative status of understorey bird species. Last, frugivores and omnivores have reduced body size in the logged forest compared to unlogged, pointing to potential functional consequences related to seed dispersal.