Indicator Of Physiological State Research Articles

Epidemiological Study of Parasites of the Edible Scallop Aequipecten tehuelchus in Patagonia, Southwest Atlantic Ocean.

This study assesses the health status of the edible Tehuelche scallop, Aequipecten tehuelchus, reporting the epidemiological results of the parasites and their infection levels by histopathological analysis and transmission electron microscopy. Environmental factors (site: West and East domains of the San José gulf, seawater temperature) and host traits (size, physiological condition index, gonad development stages) associated with parasite load (prevalence, mean intensity, parasite abundance and total parasite abundance) were tested with generalised linear models (GLMs). Histopathological results revealed Rickettsia-like organisms (RLOs), several protozoans (Trichodina sp., Nematopsis sp. and APXSc apicomplexans) and metazoans (turbellarians and Tumidotheres maculatus pea crabs) as well as inflammatory lesions in form of granulomas and hemocytic infiltration. The prevalence of the parasitofauna did not vary significantly between gulf domains, except the apicomplexan APXSc that was significantly most prevalent in scallops from the East Domain. However, the mean intensity of infection seemed to be determined by the gulf domains, which present distinct hydrographic regimes, where RLO's, Trichodina sp. and T. maculatus were significantly more intense in scallops from the West, opposite with Nematopsis sp. infection. Total parasite abundance was influenced by seasonal variations, it was negatively correlated with warmer temperatures. The physiological condition index of A. tehuelchus seemed not to be affected by the presence or abundance of any of the parasites. Nevertheless, the apicomplexan APXSc would represent a significant risk to the health of A. tehuelchus due to the pathological conditions, and surveillance of this parasite is needed for a sustainable A. tehuelchus fishery.

A Golgi-targeted fluorescent probe for monitoring polarity dynamic during programmed cell death

Programmed cell death (PCD) is a controlled form of cell death and it plays an essential role in maintaining homeostasis. Golgi apparatus works as the hotspot during the early event of PCD and Golgi polarity, a vital microenvironment factor, can be regarded as an indicator of physiological status. Combined Golgi-targeted group phenylsulfonamide as electron acceptor group and triphenylamine as electron donor group, a novel Golgi-targeted fluorescent probe GTO had been developed. GTO showed good sensitivity and selectivity to polarity and its remarkable photostability makes it potentially useful for long-term cellular monitoring. In practice, GTO demonstrated good cell permeability and Golgi targeting capabilities. According to our results, GTO was applied to reveal the polarity increase during the early event of PCD and the encouraging results illustrated that GTO was an imaging tool for monitoring polarity in Golgi apparatus and the exploration in early diagnosis and drug discovery.

Characteristics of courtship calls that could provide clues to physiological state or genetics of the emperor penguin, Aptenodytes forsteri: A case study of analysis using the Teager-Kaiser energy operator

Vocal behavior can be an indicator of physiological state or genetic make-up, but has not been developed as a diagnostic tool in seabirds. Aptenodytes penguins lack external sexual dimorphism, but the sexes have dimorphic courtship calls. We present a case study in which unique call structure of an emperor penguin (Aptenodytes forsteri) was associated with a same-sex bonded pair. Typical males produce lower frequency calls with proportionally more long bursts, while typical females produce slightly higher frequency calls with proportionally more short bursts. We recorded two male emperor penguins (E-79 and E-81) at SeaWorld San Diego that behaved as a bonded pair. E-79 produced a call that was qualitatively different from the male type to human listeners. Using the Teager-Kaiser Energy Operator to visualize bursts, we calculated and compared burst rates of E-79 and E-81 to other emperor penguins in the SeaWorld colony and a colony at Cape Crozier, Antarctica. Analysis showed E-79’s calls had a unique burst rate structure that was intermediate between typical male and female patterns. Our results suggest that while emperor courtship calls are usually strongly sexually dimorphic, it is not always the case. The exceptions could provide interesting insights into call development, physiology, and/or genetics.

The effects of diet-shifting from invertebrates towards fruit on the condition of autumn-migrant Catharus thrushes.

Migration is an energetically challenging and risky life history stage for many animals, but could be supported by dietary choices en route, which may create opportunities to improve body and physiological condition. However, proposed benefits of diet shifts, such as between seasonally available invertebrates and fruits, have received limited investigation in free-living animals. We quantified diet composition and magnitude of autumn diet shifts over two time periods in two closely-related species of migratory songbirds on stopover in the northeastern U.S. (Swainson's thrush [Catharus ustulatus], long-distance migrant, N = 83; hermit thrush [C. guttatus], short-distance migrant, N = 79) and used piecewise structural equation models to evaluate the relationships among (1) migration timing, (2) dietary behavior, and (3) morphometric and physiological condition indices. Tissue isotope composition indicated that both species shifted towards greater fruit consumption. Larger shifts in recent weeks corresponded to higher body condition in Swainson's, but not hermit thrushes, and condition was more heavily influenced by capture date in Swainson's thrushes. Presence of "high-antioxidant" fruits in fecal samples was unrelated to condition in Swainson's thrushes and negatively related to multiple condition indices in hermit thrushes, possibly indicating the value of fruits during migration is related more to their energy and/or macronutrient content than antioxidant content. Our results suggest that increased frugivory during autumn migration can support condition, but those benefits might depend on migration strategy: a longer-distance, more capital-dependent migration strategy could require stricter regulation of body condition aided by increased fruit consumption.

Meta-Analysis of the Effects of Overexpressed bZIP Transcription Factors in Plants under Drought Stress

The bZIP (basic leucine zipper) transcription factors have been identified as key regulators of plant responses to drought stress, which limits plant growth and yield. Overexpression of bZIP genes has shown potential in enhancing drought tolerance in various plant species. However, the constrained types of individual studies and inconsistencies among experimental approaches has resulted in a lack of statistical significance and limited the extrapolation of bZIP transcription factor overexpression for plant improvement. We conducted a meta-analysis to evaluate ten measured parameters of drought tolerance in bZIP transcription factor-expressing plants as well as moderators affecting the performance of transgenic plants. The results showed that seven parameters, including survival rate as well as the content of regulatory substances (proline accumulation, H2O2 concentration, CAT activity, POD activity, SOD activity and MDA accumulation), were most affected while the impact on physiological status indicators is not significant. In addition, donor/recipient species, treatment medium, duration and methods of simulating drought stress all significantly impacted the degree of drought stress tolerance in plants to some extent among the considered moderators. The findings underscore the potential of bZIP transcription factors as key targets for genetic engineering approaches aimed at improving plant resilience to water scarcity.

The habitat quality paradox: loss of riparian forest cover leads to decreased risk of parasitism and improved body condition in an imperiled amphibian.

Amphibian declines are a global phenomenon but responses of populations to specific threats are often context dependent and mediated by individual physiological condition. Habitat degradation due to reduced riparian forest cover and parasitism are two threats facing the hellbender salamander (Cryptobranchus alleganiensis), but their potential to interact in nature remains largely unexplored. We investigated associations between forest cover, parasitic infection and physiology of hellbenders to test the hypotheses that physiological condition responds to infection and/or habitat degradation. We sampled 17 stream reaches in southwest Virginia, USA, on a year-round basis from 2013 to 2016 and recorded 841 captures of 405 unique hellbenders. At each capture we documented prevalence of two blood-associated parasites (a leech and trypanosome) and quantified up to three physiological condition indices (body condition, hematocrit, white blood cell [WBC] differentials). We used generalized linear mixed models to describe spatiotemporal variation in parasitic infection and each condition index. In general, living in the most heavily forested stream reaches, where hellbender density was highest, was associated with the greatest risk of parasitism, elevated neutrophil-to-lymphocyte (N:L) ratios and eosinophils, slightly lower hematocrit and lower mean body condition in hellbenders. All condition indices fluctuated temporally in a manner consistent with seasonal variation in hellbender metabolic demands and breeding phenology and were associated with land use during at least part of the year. Paradoxically, relatively low levels of forest cover appeared to confer a potential advantage to individuals in the form of release from parasites and improved body condition. Despite improved body condition, individuals from less forested areas failed to exhibit fluctuating body condition in response to spawning, which was typical in hellbenders from more forested habitats. We postulate this lack of fluctuation could be due to reduced conspecific competition or reproductive investment and/or high rates of filial cannibalism in response to declining forest cover.

Investigation of the expression levels of miR-21, miR-132, miR-29a, miR-204, and miR-138 in patient's plasma with primary OSCCs

This is the eighth most malignant tumor in the world, causing the highest incidence and malignancy rate of all cancers in the mouth and maxillofacial region. In cells, miRNAs regulate development, differentiation, proliferation, and differentiation, and miRNA expression is a better indicator of physiological status than DNA expression. miR-21, miR-132, miR-29a, miR-204, and miR-138 levels were measured in plasma from patients with primary OSCC and healthy controls. A Real Time-PCR technique was used to measure miR-21, miR-132, miR-29a, miR-29a, and miR-204 expression levels in plasma from 38 healthy and 38 people with primary OSCC. A standard distribution test and a CT unit were used to confirm the quantitative data on miRNA expression. Gene expression levels were compared between two groups of patients and healthy groups using a Mann-Whitney test and an unpaired t-test. MiR-21's median CT value was 29.68 in the OSCC group and 32.89 in the healthy group, and miR-29a's median CT value was 37.54 and 36.46 in the OSCC group and healthy group, respectively. Additionally, miR-132's CT values were 37.71 and 36.40, miR-138's CT value was 35.37 and 31.21, and miR-204's CT value was 36.44 and 36.17. The results showed that miR-21 expression levels increased significantly, while miR-29a, miR-132, and miR-138 (P < 0.05), and miR-204 expression levels did not differ significantly (P > 0.05). As a result of this study, the expression levels of microRNAs may be considered to diagnose OSCC at an early stage. It is essential to diagnose this disease early to improve treatment and patient health outcomes.

Nitrogen and phosphorus as macronutrients of cocoa (Theobroma cacao) and their physiological functions in different planting patterns of cultivation in Central Java, Indonesia

Plant physiological status during the growing season (specific leaf area (SLA), resorption of N and P)leads to knowing the best plant nutrition management (amount and time) based on the plating pattern. Furthermore, proline and glucose content in root tissues may provide a better technique to represent plant stress conditions. This study aimed to evaluate the SLA, the level of reabsorption of N and P from the leaf, and root proline and glucose content of cocoa plants in different seasons and planting patterns. This study was performed in the fields of Plana village, Somagede, Banyumas, 14 Central Java, Indonesia, and was conducted in December 2015 (rainy season) and October 2016 (dry season) on 7 years-old cocoa plants (Theobroma cacao). Three different planting patterns were observed; (1) only cocoa plants, (2) cocoa and coconut pattern, and (3) cocoa with shading trees. The results showed that different seasons and planting patterns affected each observed parameter differently. Cocoas’ SLA was not significantly different in all areas for both 2015 and 2016. N resorption during the growing season did not change in 2015 and 2016 in all planting patterns, whereas P resorption had a significant change in 2016 in all planting patterns. The proline content was significantly different in June 2015, October 2015, and March 2016 in all planting patterns. The glucose content in roots showed insignificant differences in 2015 and 2016 in all planting patterns. These results also showed that SLA and glucose did respond to season and plating patterns. These parameters are suggested as poor indicators of physiological status. Furthermore, sowing cocoa plants with other types of plants can be used to help farmers and stakeholders in managing cocoa cultivation in efficient and sustainable ways.

STUDY OF SEASONAL VARIATIONS OF THE CONDITION INDICES IN THE MUSSEL Mytilus galloprovincialis: RELATIONSHIP WITH PHYSICO-CHEMICAL PARAMETERS, BIOMARKERS AND METALS IN THE REGION OF SIDI IFNI (SOUTH OF MOROCCO)

The aim of this work is studying the correlation between seasonal variations of physiological condition indices, as physiological state and growth indicator, and biomarkers of pollution (Acetylcholinesterase, Glutathione S-transferase, Catalase, Malondialdehyde and Metallothioneins) in Mytilus galloprovincialis in three sites representative of Sidi Ifni’s coastline (South Atlantic of Morocco): Mirleft site (S1), Cheikh Sidi Ali Ifni (S2) and Tazrout site (S3). The study showed a pronounced variability in the biological and physiological behavior of mussel populations from Sidi Ifni coasts. The comparison of the results of physiological condition indices in Mytilus galloprovincialis with environmental factors and biochemical markers shows that the species is contaminated in the Ifni site compared to Mirleft and Tazrout.

Aminomethylphosphonic acid (AMPA) alters oxidative status during embryonic development in an amphibian species

Glyphosate's primary metabolite (aminomethylphosphonic acid, AMPA) is known to alter embryonic development at environmentally relevant concentrations in amphibians. However, we have limited understanding of the physiological mechanisms through which AMPA affects organisms. In this study, we tested whether alteration of the oxidative status is one mechanism through which AMPA affects organism performance. To this end, we analysed several oxidative status markers in hatchling tadpoles that were exposed to sublethal concentrations of AMPA during embryonic development (~16 days). We compared the influence of environmentally relevant concentrations of AMPA (from 0.07 to 3.57 μg l−1) on the relation between developmental traits (i.e, embryonic development duration, embryonic mortality and hatchling size) and oxidative status markers known to alter homeostasis when unbalanced (superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), thiols and ratios thereof). We included measures of telomere length as an indicator of physiological state. We found that AMPA concentrations induce non-monotonic effects on some oxidative status markers with hatchlings displaying elevated antioxidant responses (elevated thiols and unbalanced SOD/(GPx + CAT) ratio). The lack of effect of AMPA on the relation between developmental traits, oxidative status and telomere length suggests that selective mortality of embryos susceptible to oxidative stress may have occurred prior to hatching in individuals less resistant to AMPA which display lower hatching success. Future studies are required to disentangle whether oxidative unbalance is a cause or a consequence of AMPA exposition. This study highlights the need to investigate effects of the metabolites of contaminants at environmental concentrations to comprehensively assess impacts of anthropogenic contamination on wildlife.

The extent of white plumage patches in female Pied Flycatchers Ficedula hypoleuca is negatively associated with corticosterone concentration in partly unpigmented feathers

Sexually and socially selected signals are predicated to express the present and past condition of individuals and thereby their capacity to cope with environmental challenges. The concentration of corticosterone in feathers (CORTf) has been validated as a marker of activation of the hypothalamic-pituitary axis in birds during feather development. Measurements of CORTf can thus express the physiological stress of migratory birds during non-breeding periods of the annual cycle when feathers moulted in the wintering range are analysed. Thus, negative trends of ornament expression with CORTf may be predicted. Unpigmented plumage patches may constitute signals of phenotypic quality and are used in many species in social interactions by both sexes. Pied Flycatchers of both sexes Ficedula hypoleuca show white forehead and wing patches during the breeding season, of which the forehead and part of the wing patch (tertials) are moulted on the wintering grounds before spring migration. These patches are used as signals in social and sexual interactions and their expression has been previously related to several indicators of physiological status. We collected tertials of females during nestling provisioning in a Spanish population and determined their CORTf in the laboratory. CORTf was thus measured in some of the prenuptially moulted feathers used as signals of social dominance by breeding females. According to AICc model selection, CORTf turned up in all the best models explaining forehead patch size and in most best models for wing patch size when controlling for age and size. Both forehead and wing patch sizes were negatively related to CORTf, although the trend for wing patch size was not significant. This indicates that breeding females expressing large unpigmented patches experienced low levels of stress during the prenuptial moult in their winter quarters, or that strongly signalling individuals present a lower level of activation of the HPA axis.

Detecting Cynoglossus semilaevis infected with Vibrio harveyi using micro RNAs from mucous exosomes

Exosomes are important mediators of vesicle transportation and contain microRNAs (miRNAs) that mediate transcriptional gene knockout and silencing in biological processes. Moreover, exosomic miRNAs are promising biomarkers for disease diagnosis and physiological status indication in many species, including fish. The impact of the Vibrio harveyi pathogen on Cynoglossus semilaevis aquaculture is becoming more and more serious as the industry expands. To overcome this challenge, miRNAs in mucous exosomes were screened by small RNA sequencing and verified by quantitative real-time PCR to develop biomarkers. This is the first capture of exosomes from flatfish mucus coupled with miRNA profiling. The results revealed significant differences in expression levels of some miRNAs between infected and healthy fish. Three unique miRNAs were identified for V. harveyi infection diagnosis; expression levels of dre-miR-205-5p and dre-miR-205-5p in infected fish were significantly lower than controls, while dre-miR-100-5p expression was higher. These miRNAs in mucous exosomes could be used to differentiate diseased and healthy fish in an early screening method with practical value for breeding disease-resistant C. semilaevis.

Relationship of morphometrics, total carotenoids, and total lipids with activity and sexual and spatial features in Euphausia superba

Morphological differences associated with sex or stage, together with total lipids and carotenoids, were studied in Euphausia superba as possible indicators of physiological condition. E. superba displays sexual dimorphism during growth. A group of mature males, called Males II herein, has a greater abdominal length, suggesting that they are faster swimmers, a feature implying higher metabolic rates and a higher demand for protecting pigments like carotenoids. Mature Males II have proportionally lower lipids but higher total lipid-soluble carotenoids, a counterintuitive finding. Males II also have bigger eyes. Significant regressions with carotenoids were found for wet weight, abdominal length, and eye diameter. On a spatial analysis, population composition reflects reproductive activity. Males II would be in search of females for fecundation and, thus, are dominant in some areas. The PCA analysis of 10 allometric and biochemical variables show a distinct Males II group differing in morphology, carotenoids, and lipid contents. The carotenoid:lipid ratio was highest for Males II, supporting the hypothesis of the role of carotenoids in the activity of the species. Mature males may experience physiological stress during reproduction and probably die shortly afterwards. A relationship between activity, morphometrics, and carotenoid content seems evident, deserving further investigation.

Identification and application of piwi-interacting RNAs from seminal plasma exosomes in Cynoglossus semilaevis

BackgroundPiwi-interacting RNAs (piRNAs) have been linked to epigenetic and post-transcriptional gene silencing of retrotransposons in germ line cells, particularly in spermatogenesis. Exosomes are important mediators of vesicle transport, and the piRNAs in exosomes might play an important role in cell communication and signal pathway regulation. Moreover, exosomic piRNAs are promising biomarkers for disease diagnosis and physiological status indication. We used Cynoglossus semilaevis because of its commercial value and its sexual dimorphism, particularly the sex reversed “pseudomales” who have a female karyotype, produce sperm, and copulate with normal females to produce viable offspring.ResultsTo determine whether piRNAs from fish germ line cells have similar features, seminal plasma exosomes from half-smooth tongue sole, C. semilaevis, were identified, and their small RNAs were sequenced and analysed. We identified six signature piRNAs as biomarkers in exosomes of seminal plasma from males and pseudomale C. semilaevis. Bioinformatic analysis showed that all six signatures were sex-related, and four were DNA methylation-related and transposition-related piRNAs. Their expression profiles were verified using real-time quantitative PCR. The expression of the signature piRNAs was markedly higher in males than in pseudomales. The signature piRNAs could be exploited as male-specific biomarkers in this fish.ConclusionsThese signatures provide an effective tool to explore the regulatory mechanism of sex development in C. semilaevis and may provide guidance for future research on the function of piRNAs in the generative mechanism of sex reversed “pseudomales” in C. semilaevis.

ФИЗИОЛОГИЧЕСКИЙ СТАТУС СТУДЕНТОВ С РАЗЛИЧНЫМ УРОВНЕМ ДВИГАТЕЛЬНОЙ АКТИВНОСТИ

The study of the dynamics of physiological status indicators is the basic foundation of the structure of preventive health-improving measures aimed at restoring and strengthening the functional reserves of students. The aim of the study is to study the dynamics of physiological parameters in students with different levels of motor activity during the period of study at the university. Materials and methods. A prospective observation of the physical health of 615 students (255 boys and 360 girls) 17–22 years old was carried out during 2010–2019 using the Student Health Diary, according to the tasks of which anthropometric measurements were performed annually. The level of motor activity was determined by the results of the survey and was evaluated by the number of points scored: low, medium and high. Results. The study revealed that during the period of study at a university, most students undergo a change in their physiological status due to the level of physical activity: the higher it is, the more intense the growth of physiological parameters and the more stable the vegetative status. In senior courses, a quarter of students have a decrease in the level of physical activity, which is explained by the absence of physical education classes in the 4–5 courses in the educational process. As a result, students lose their accumulated functional reserves, a decrease in physiological parameters and the stability of the vegetative status are noted. It was revealed that girls lead a more active lifestyle, this is confirmed by a greater number of students with a high level of motor activity, a greater number of girls with growth in physiological status indicators and during the period of training, girls lose less physical activity than boys. The results of the study emphasize the importance of physical activity for students. Natural, i.e. physiological growth of indicators is carried out only with an average and high level of motor activity, and more intensively against the background of the latter. Also, during the study, students were identified who have a negative dynamics of physiological status. Conclusion The obtained results confirm that in order to maintain the physiological status at the optimal level, it is necessary to form the students’ physical culture throughout the entire period of study at the university, taking into account the level of health and physical fitness.

Changes in food characteristics reveal indirect effects of lake browning on zooplankton performance

AbstractBrowning caused by colored dissolved organic matter is predicted to have large effects on aquatic ecosystems. However, there is limited experimental evidence about direct and indirect effects of browning on zooplankton in complex field settings. We used a combination of an ecosystem‐scale enclosure experiment and laboratory incubations to test how prolonged browning affects physiological and life‐history traits of the water flea Daphnia longispina, a key species in lake food webs, and whether any such effects are reversible. Daphnids and water were collected from enclosures in a deep clear‐water lake, where the natural plankton community had been exposed for 10 weeks to browning or to control conditions in clear water. Daphnid abundance was much lower in the brown than in the clear enclosure. Surprisingly, however, daphnids continuously kept in brown enclosure water in the laboratory showed increased metabolic performance and survival, and also produced more offspring than daphnids kept in clear enclosure water. This outcome was related to more and higher‐quality seston in brown compared to clear water. Moreover, daphnids transferred from clear to brown water or vice versa adjusted their nucleic acid and protein contents, as indicators of physiological state, to similar levels as individuals previously exposed to the respective recipient environment, indicating immediate and reversible browning effects on metabolic performance. These results demonstrate the importance of conducting experiments in settings that capture both indirect effects (i.e., emerging from species interactions in communities) and direct effects on individuals for assessing impacts of browning and other environmental changes on lakes.

Blubber steroid hormone profiles as indicators of physiological state in free-ranging common bottlenose dolphins (Tursiops truncatus)

Blubber has been proposed as a possible alternative to blood in the assessment of endocrine physiology in marine mammals because it can be collected via remote biopsy, which removes some of the confounding variables and logistical constraints associated with blood collection. To date, few studies have directly assessed the relationships between circulating versus blubber steroid hormone profiles in marine mammals, and these studies have been limited to a small subset of steroid hormones, which collectively limit the current utility of blubber steroid hormone measurements. In this study, we used liquid-chromatography tandem-mass spectrometry (LC-MS/MS) to screen for 16 steroid hormones in matched blood and blubber samples from free-ranging common bottlenose dolphins (Tursiops truncatus). Seven steroid hormones were detected and quantified, including two progestogens, two androgens, and three corticosteroids. Using principal components analysis (PCA), we explored relationships between hormones in both matrices and three physiological states: sexual maturity, pregnancy, and acute stress response. Plasma and blubber testosterone and its precursors, 17-hydroxyprogesterone and androstenedione, loaded to the first principal component (PC1), and PC1 scores were higher in mature males. Plasma and blubber progesterone loaded to PC2, and pregnant/probable pregnant females had significantly higher PC2 scores. Pregnant females also had higher PC1 scores than other females, suggesting differences in androgen profiles between these groups. There was disagreement between plasma and blubber corticosteroid profiles, as indicated by their loading to different PCs; plasma corticosteroids loaded to PC3 and blubber corticosteroids to PC4. PC3 scores were significantly predicted by elapsed time to blood collection (i.e., time between initiating the capture process and blood collection), while elapsed time to blubber collection significantly predicted PC4 scores, indicating that corticosteroid profiles shift in both tissues during acute stress. Corticosteroid profiles were not related to demographic group, site-month, body mass index, water temperature, or time spent outside of the water on the processing boat. Overall, these results demonstrate that blubber steroid hormone profiles reflect changes in endocrine function that occur over broad temporal scales.

Effect of Culture Depth and Season on the Condition and Reproductive Indices of Blue Mussels (Mytilus edulis L.) Cultured in a Cold-Water Coastal Environment

Condition, growth, and reproductive indices of blue mussels (Mytilus edulis) grown in deep and shallow sites were studied from May to December 2016 in the South Arm region of Notre Dame Bay, Newfoundland. The region was shown to be characterized by a seasonal thermocline that formed in April and lasted to October annually, resulting in a cold-water deep layer (mean annual temperature: 4.36 ± 5.1°C) and a comparatively warmer surface layer (mean annual temperature: 5.81 ± 6.3°C). The deepwater culture sites extended into the cold-water layer and the shallow sites were typically in the warmer layer above. Mussels grown in shallow sites had longer and heavier shells than those from deepwater sites, likely linked to warmer surface waters. Both reproductive and physiological condition indices were high for mussels from both culture depths in May. Physiological condition declined for both deep and shallow cultured mussels from May through to August. Mussels from deep sites, however, had a higher overall mean dry tissue weight: wet tissue weight ratio for the study period. Reproductive indices, including measurements of reproductive output, declined for shallow mussels from May through to August, but remained high for deep mussels until August when a significant spawn occurred for mussels from both depths. In addition, mussels from deep sites were observed to maintain themselves in a prespawning ripe stage for a longer period than those from shallow sites. Variations in physiological and reproductive indices for mussels from each respective culture depth were thought to be linked to differences in the environmental characteristics of the deep and shallow water layers, including rate of temperature change and potential differences in phytoplankton quality and energetics. The additional data provided in the present study add to the current understanding of the effects of the deepwater environment on mussel reproduction patterns and its relationship to production meat yield. The data will help in highlighting the benefits of using deepwater sites leading to increased environmental sustainability for mussel culture in subarctic coastal environments such as those on the north coast of Newfoundland.

The effect of thermal pre-incubation and exposure on sensitivity of zebrafish (Danio rerio) to copper and cadmium single and binary exposures

Zebrafish (Danio rerio) is a prominent model organism in a wide range of biological studies including toxicology. However, toxicological studies are often performed at species specific optimum temperature, and knowledge on the effect of different temperature regimes on the toxicity of metal ions is rather limited. To address this knowledge gap, present study investigates the effect of various thermal scenarios (simultaneous and sequential; acute and chronic) on the toxicity of Cu and Cd in zebrafish. For this purpose we assessed mortality and whole body metal burdens as indicators of toxicity and bioavailability, respectively, and whole body electrolyte concentrations and body condition as the indicators of physiological condition. Thermal pre-incubations (for 12 or 96 h or 28 days) and subsequent metal ion exposures (for 10 days) were conducted at 17, 22, 25, 28, 32 and 34 °C. The metal exposures were performed at Cu concentrations of 1.2 μM and Cd concentrations of 0.2 μM, both singly and in binary mixtures. Irrespective of thermal treatments, Cu exposures resulted in greater mortality than Cd exposures at the given concentrations. Moreover, the Cu and Cd mixture indicated a synergistic effect. While acute pre-incubation for 12 or 96 h at elevated temperatures increased mortality in the subsequent metal exposure at the optimum temperature (28 °C), pre-incubation at cold temperatures in this scenario appeared to increase tolerance towards the subsequent metal exposure. Chronic thermal pre-incubation of zebrafish to a range of temperatures for 28 days moderated the effect of temperature fluctuations on subsequent metal toxicity at the optimum temperature. Chronic thermal pre-incubation at a range of temperatures followed by metal exposure at the same temperature showed that environmental temperature variations (higher or lower than optimal temperature) coupled with metal exposure, led to increased mortality, furthermore, the highest whole body metal burdens were measured in this scenario. Nevertheless, neither the whole body burden of metals, nor the metal accumulation rate, were predictors of mortality, i.e. these two values were not higher in dead fish in comparison to those that survived the exposures. Finally, we observed a significant decrease in the whole body Na+ level of dead fish in comparison to fish which survived the exposure conditions, suggesting that survival depends on maintaining Na+ homeostasis under the applied multi-stress conditions. Overall, our results show that thermal pre-history and ambient temperature play an important role in determining the tolerance of zebrafish towards metal ion stress.

Differences between Men and Women in Mortality and the Health Dimensions of the Morbidity Process.

Do men have worse health than women? This question is addressed by examining sex differences in mortality and the health dimensions of the morbidity process that characterize health change with age. We also discuss health differences across historical time and between countries. Results from national-level surveys and data systems are used to identify male/female differences in mortality rates, prevalence of diseases, physical functioning, and indicators of physiological status. Male/female differences in health outcomes depend on epidemiological and social circumstances and behaviors, and many are not consistent across historical time and between countries. In all countries, male life expectancy is now lower than female life expectancy, but this was not true in the past. In most countries, women have more problems performing instrumental activities of daily living, and men do better in measured performance of functioning. Men tend to have more cardiovascular diseases; women, more inflammatory-related diseases. Sex differences in major cardiovascular risk factors vary between countries-men tend to have more hypertension; women, more raised lipids. Indicators of physiological dysregulation indicate greater inflammatory activity for women and generally higher cardiovascular risk for men, although women have higher or similar cardiovascular risk in some markers depending on the historical time and country. In some aspects of health, men do worse; in others, women do worse. The lack of consistency across historical times and between countries in sex differences in health points to the complexity and the substantial challenges in extrapolating future trends in sex differences.