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1.
Nature ; 572(7770): 461-466, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31340216

RESUMO

Effective ocean management and the conservation of highly migratory species depend on resolving the overlap between animal movements and distributions, and fishing effort. However, this information is lacking at a global scale. Here we show, using a big-data approach that combines satellite-tracked movements of pelagic sharks and global fishing fleets, that 24% of the mean monthly space used by sharks falls under the footprint of pelagic longline fisheries. Space-use hotspots of commercially valuable sharks and of internationally protected species had the highest overlap with longlines (up to 76% and 64%, respectively), and were also associated with significant increases in fishing effort. We conclude that pelagic sharks have limited spatial refuge from current levels of fishing effort in marine areas beyond national jurisdictions (the high seas). Our results demonstrate an urgent need for conservation and management measures at high-seas hotspots of shark space use, and highlight the potential of simultaneous satellite surveillance of megafauna and fishers as a tool for near-real-time, dynamic management.


Assuntos
Migração Animal , Pesqueiros/estatística & dados numéricos , Mapeamento Geográfico , Oceanos e Mares , Tubarões/fisiologia , Análise Espaço-Temporal , Animais , Densidade Demográfica , Medição de Risco , Tubarões/classificação , Navios , Fatores de Tempo
2.
Proc Biol Sci ; 290(1996): 20230262, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-37040803

RESUMO

Understanding the factors shaping patterns of ecological resilience is critical for mitigating the loss of global biodiversity. Throughout aquatic environments, highly mobile predators are thought to serve as important vectors of energy between ecosystems thereby promoting stability and resilience. However, the role these predators play in connecting food webs and promoting energy flow remains poorly understood in most contexts. Using carbon and nitrogen isotopes, we quantified the use of several prey resource pools (small oceanic forage, large oceanics, coral reef, and seagrass) by 17 species of elasmobranch fishes (n = 351 individuals) in The Bahamas to determine their functional diversity and roles as ecosystem links. We observed remarkable functional diversity across species and identified four major groups responsible for connecting discrete regions of the seascape. Elasmobranchs were responsible for promoting energetic connectivity between neritic, oceanic and deep-sea ecosystems. Our findings illustrate how mobile predators promote ecosystem connectivity, underscoring their functional significance and role in supporting ecological resilience. More broadly, strong predator conservation efforts in developing island nations, such as The Bahamas, are likely to yield ecological benefits that enhance the resilience of marine ecosystems to combat imminent threats such as habitat degradation and climate change.


Assuntos
Ecossistema , Elasmobrânquios , Animais , Recifes de Corais , Biodiversidade , Peixes
5.
J Occup Environ Hyg ; 19(1): 1-11, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34731075

RESUMO

Cleaners have an elevated risk for the development or exacerbation of asthma and other respiratory conditions, possibly due to exposure to cleaning products containing volatile organic compounds (VOCs) leading to inflammation and oxidative stress. This pilot study aimed to quantify total personal exposure to VOCs and to assess biomarkers of inflammation and pulmonary oxidative stress in 15 predominantly Hispanic women working as domestic cleaners in San Antonio, Texas, between November 2019 and July 2020. In partnership with a community organization, Domésticas Unidas, recruited women were invited to attend a training session where they were provided 3M 3500 passive organic vapor monitors (badges) and began a 72-hr sampling period during which they were instructed to wear one badge during the entire period ("AT," for All the Time), a second badge only while they were inside their home ("INS," for INSide), and a third badge only when they were outside their home ("OUT," for OUTside). At the end of the sampling period, women returned the badges and provided blood and exhaled breath condensate (EBC) samples. From the badges, 30 individual VOCs were measured and summed to inform total VOC (TVOC) concentrations, as well as concentrations of the following VOC groups: aromatic hydrocarbons, alkanes, halogenated hydrocarbons, and terpenes. From the blood and EBC samples, concentrations of serum C-reactive protein (CRP) and EBC 8-isoprostane (8-ISP) and pH were quantified. Data analyses included descriptive statistics. The 72-hr average of personal exposure to TVOC was 34.4 ppb and ranged from 9.2 to 219.5 ppb. The most prevalent class of VOC exposures for most women (66.7%) was terpenes, specifically d-limonene. Overall, most women also experienced higher TVOC concentrations while outside their home (86.7%) as compared to inside their home. Serum CRP concentrations ranged from 0.3 to 20.3 mg/dL; 8-ISP concentrations ranged from 9.5 to 44.1 pg/mL; and EBC pH ranged from 7.1 to 8.6. Overall, this pilot study demonstrated personal VOC exposure among Hispanic domestic cleaners, particularly to d-limonene, which may result from the use of scented cleaning products.


Assuntos
Compostos Orgânicos Voláteis , Feminino , Hispânico ou Latino , Humanos , Inflamação , Limoneno , Projetos Piloto
6.
J Immunol ; 203(9): 2520-2531, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31562213

RESUMO

The innate immune sensing of allergens or allergen-associated components regulate the development of type 2 inflammatory responses. However, the underlying molecular basis by which allergens or allergen-associated components are detected by innate immune receptors remains elusive. In this study, we report that the most common aeroallergen, house dust mite (HDM), harbors a dsRNA species (HDM-dsRNA) that can activate TLR3-mediated IFN responses and counteract the development of an uncontrolled type 2 immune response. We demonstrate that the mouse strains defective in the dsRNA-sensing pathways show aggravated type 2 inflammation defined by severe eosinophilia, elevated level of type 2 cytokines, and mucus overproduction in a model of allergic lung inflammation. The inability to sense HDM-dsRNA resulted in significant increases in airway hyperreactivity. We further show that the administration of the purified HDM-dsRNA at a low dose is sufficient to induce an immune response to prevent the onset of a severe type 2 lung inflammation. Collectively, these results unveil a new role for the HDM-dsRNA/TLR3-signaling axis in the modulation of a type 2 lung inflammation in mice.


Assuntos
Alérgenos/imunologia , Interferons/biossíntese , Pneumonia/etiologia , Pyroglyphidae/imunologia , RNA de Cadeia Dupla/imunologia , Animais , Humanos , Imunidade Inata , Camundongos , Camundongos Endogâmicos C57BL , Hipersensibilidade Respiratória/etiologia , Transdução de Sinais/fisiologia , Receptor 3 Toll-Like/fisiologia
7.
J Allergy Clin Immunol ; 146(6): 1217-1270, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33280709

RESUMO

The 2020 Focused Updates to the Asthma Management Guidelines: A Report from the National Asthma Education and Prevention Program Coordinating Committee Expert Panel Working Group was coordinated and supported by the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health. It is designed to improve patient care and support informed decision making about asthma management in the clinical setting. This update addresses six priority topic areas as determined by the state of the science at the time of a needs assessment, and input from multiple stakeholders:A rigorous process was undertaken to develop these evidence-based guidelines. The Agency for Healthcare Research and Quality's (AHRQ) Evidence-Based Practice Centers conducted systematic reviews on these topics, which were used by the Expert Panel Working Group as a basis for developing recommendations and guidance. The Expert Panel used GRADE (Grading of Recommendations, Assessment, Development and Evaluation), an internationally accepted framework, in consultation with an experienced methodology team for determining the certainty of evidence and the direction and strength of recommendations based on the evidence. Practical implementation guidance for each recommendation incorporates findings from NHLBI-led patient, caregiver, and clinician focus groups. To assist clincians in implementing these recommendations into patient care, the new recommendations have been integrated into the existing Expert Panel Report-3 (EPR-3) asthma management step diagram format.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Humanos , Guias de Prática Clínica como Assunto
8.
Mol Biol Evol ; 36(1): 84-96, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30364966

RESUMO

Birds, mammals, and certain fishes, including tunas, opahs and lamnid sharks, are endothermic, conserving internally generated, metabolic heat to maintain body or tissue temperatures above that of the environment. Bluefin tunas are commercially important fishes worldwide, and some populations are threatened. They are renowned for their endothermy, maintaining elevated temperatures of the oxidative locomotor muscle, viscera, brain and eyes, and occupying cold, productive high-latitude waters. Less cold-tolerant tunas, such as yellowfin tuna, by contrast, remain in warm-temperate to tropical waters year-round, reproducing more rapidly than most temperate bluefin tuna populations, providing resiliency in the face of large-scale industrial fisheries. Despite the importance of these traits to not only fisheries but also habitat utilization and responses to climate change, little is known of the genetic processes underlying the diversification of tunas. In collecting and analyzing sequence data across 29,556 genes, we found that parallel selection on standing genetic variation is associated with the evolution of endothermy in bluefin tunas. This includes two shared substitutions in genes encoding glycerol-3 phosphate dehydrogenase, an enzyme that contributes to thermogenesis in bumblebees and mammals, as well as four genes involved in the Krebs cycle, oxidative phosphorylation, ß-oxidation, and superoxide removal. Using phylogenetic techniques, we further illustrate that the eight Thunnus species are genetically distinct, but found evidence of mitochondrial genome introgression across two species. Phylogeny-based metrics highlight conservation needs for some of these species.


Assuntos
Evolução Biológica , Termogênese/genética , Atum/genética , Animais , Espécies em Perigo de Extinção , Genoma Mitocondrial , Hibridização Genética , Mutação , Seleção Genética , Atum/metabolismo
9.
J Clin Microbiol ; 58(6)2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32269102

RESUMO

We evaluated six commercial molecular tests targeting Mycoplasma pneumoniae, namely, the BioFire FilmArray respiratory panel (RP), the Meridian Alethia Mycoplasma Direct, the GenMark ePlex respiratory pathogen panel (RPP), the Luminex NxTAG RPP, the ELITech ELITe InGenius Mycoplasma MGB research use only (RUO) PCR, and the SpeeDx Resistance Plus MP assays. Laboratory-developed PCR assays at the University of Alabama at Birmingham and the Centers for Disease Control and Prevention were used as reference standards. Among 428 specimens, 212 were designated confirmed positives for M. pneumoniae The highest clinical sensitivities were found with the InGenius PCR (99.5%) and the FilmArray RP (98.1%). The Resistance Plus MP identified 93.3% of the confirmed-positive specimens, whereas 83.6, 64.6, and 55.7% were identified by the ePlex RPP, NxTAG RPP, and Mycoplasma Direct assays, respectively. There was no significant difference between the sensitivity of the reference methods and that of the FilmArray RP and InGenius assays, but the remaining four assays detected significantly fewer positive specimens (P < 0.05). Specificities of all assays were 99.5 to 100%. The Resistance Plus MP assay detected macrolide resistance in 27/33 specimens, resulting in a sensitivity of 81.8%. This study provides the first large-scale comparison of commercial molecular assays for detection of M. pneumoniae in the United States and identified clear differences among their performance. Additional studies are necessary to explore the impact of various test performances on patient outcome.


Assuntos
Mycoplasma pneumoniae , Pneumonia por Mycoplasma , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Humanos , Macrolídeos/farmacologia , Mycoplasma pneumoniae/genética , Patologia Molecular , Pneumonia por Mycoplasma/diagnóstico
10.
J Sports Sci ; 38(13): 1488-1495, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32268834

RESUMO

Physical movement demands in elite netball match-play have been limited to notational analysis or accelerometer-derived measures, due in part to the indoor environment in which they are played. Commercially available local positioning systems (LPS) using ultra-wideband communication have been designed to bring similar capabilities as global positioning systems (GPS) to indoor environments. This study aims to quantify both spatiotemporal and traditional accelerometer-derived measures, to assess the movement demands of all playing positions, during Australian national netball league matches. Total distance, metreage per minute, acceleration density, acceleration density index, acceleration load, jumps, velocity bands, acceleration bands and PlayerLoad variables have been presented for each position. Mean total distance-covered in match-play differed substantially between positions. Centre position accumulated the highest mean distance (5462.1 ± 169.4 m), whilst the Goal Shooter consistently covered the lowest mean distance (2134 ± 102.6 m). Change of direction relative to movement area was highest for the two most restricted positions based on average acceleration per 10 m covered during match-play (Goal Shooter; 7.21 ± 0.88 m · s - 2 and Goal Keeper; 6.75 ± 0.37 m · s - 2, remaining positions; 5.71 ± 0.14 m · s - 2). The positional profiles outlined in this study can assist skill and conditioning coaches to prescribe training sessions that will optimise the athlete's physical preparation for the demands of competition.


Assuntos
Acelerometria/métodos , Desempenho Atlético/fisiologia , Comportamento Competitivo/fisiologia , Sistemas de Informação Geográfica , Movimento/fisiologia , Esportes/fisiologia , Adulto , Austrália , Feminino , Humanos , Estudos de Tempo e Movimento , Adulto Jovem
11.
J Fish Biol ; 96(6): 1508-1511, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32166741

RESUMO

The purpose of this study was to test the effects of high CO2 exposure on wound healing rates in an elasmobranch fish (Urobatis jamaicensis). Small dermal injuries (8 mm biopsy) closed by 22 days post wounding with a decrease in haematocrit. High CO2 exposure (ΔpH = 1.4) did not influence healing rate or haematocrit. Combined, these data provide evidence that minimally invasive scientific procedures have short-term impacts on elasmobranch fishes even during exposure to a chronic stressor. Therefore, wound healing rates may not be strongly impacted by ocean acidification (ΔpH = 0.4).


Assuntos
Dióxido de Carbono/toxicidade , Água do Mar/química , Rajidae/fisiologia , Cicatrização/efeitos dos fármacos , Animais , Concentração de Íons de Hidrogênio
12.
J Fish Biol ; 94(4): 556-577, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30838660

RESUMO

Fishes are used in a wide range of scientific studies, from conservation research with potential benefits to the species used to biomedical research with potential human benefits. Fish research can take place in both laboratories and field environments and methods used represent a continuum from non-invasive observations, handling, through to experimental manipulation. While some countries have legislation or guidance regarding the use of fish in research, many do not and there exists a diversity of scientific opinions on the sentience of fish and how we determine welfare. Nevertheless, there is a growing pressure on the scientific community to take more responsibility for the animals they work with through maximising the benefits of their research to humans or animals while minimising welfare or survival costs to their study animals. In this review, we focus primarily on the refinement of common methods used in fish research based on emerging knowledge with the aim of improving the welfare of fish used in scientific studies. We consider the use of anaesthetics and analgesics and how we mark individuals for identification purposes. We highlight the main ethical concerns facing researchers in both laboratory and field environments and identify areas that need urgent future research. We hope that this review will help inform those who wish to refine their ethical practices and stimulate thought among fish researchers for further avenues of refinement. Improved ethics and welfare of fishes will inevitably lead to increased scientific rigour and is in the best interests of both fishes and scientists.


Assuntos
Bem-Estar do Animal , Ética em Pesquisa , Peixes , Projetos de Pesquisa , Anestésicos , Animais
13.
Am J Respir Cell Mol Biol ; 58(2): 253-260, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28915064

RESUMO

Mycoplasma pneumoniae infection has been linked to poor asthma outcomes. M. pneumoniae produces an ADP-ribosylating and vacuolating toxin called community-acquired respiratory distress syndrome (CARDS) toxin that has a major role in inflammation and airway dysfunction. The objective was to evaluate the immunopathological effects in primates exposed to M. pneumoniae or CARDS toxin. A total of 13 baboons were exposed to M. pneumoniae or CARDS toxin. At Days 7 and 14, BAL fluid was collected and analyzed for cell count, percent of each type of cell, CARDS toxin by PCR, CARDS toxin by antigen capture, eosinophilic cationic protein, and cytokine profiles. Serum IgM, IgG, and IgE responses to CARDS toxin were measured. All animals had a necropsy for analysis of the histopathological changes on lungs. No animal developed signs of infection. The serological responses to CARDS toxin were variable. At Day 14, four of seven animals exposed to M. pneumoniae and all four animals exposed to CARDS toxin developed histological "asthma-like" changes. T cell intracellular cytokine analysis revealed an increasing ratio of IL-4/IFN-γ over time. Both M. pneumoniae and CARDS toxin exposure resulted in similar histopathological pulmonary changes, suggesting that CARDS toxin plays a major role in the inflammatory response.


Assuntos
Asma/imunologia , Asma/patologia , Proteínas de Bactérias/imunologia , Toxinas Bacterianas/imunologia , Pulmão/imunologia , Pulmão/patologia , Mycoplasma pneumoniae/patogenicidade , Animais , Linfócitos T CD4-Positivos/imunologia , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Interleucina-13/imunologia , Interleucina-4/imunologia , Pulmão/microbiologia , Camundongos , Mycoplasma pneumoniae/imunologia , Papio
14.
Artigo em Inglês | MEDLINE | ID: mdl-29038277

RESUMO

Ventilator-associated bacterial pneumonia (VABP) is a difficult therapeutic problem. Considerable controversy exists regarding the optimal chemotherapy for this entity. The recent guidelines of the Infectious Diseases Society of America and the American Thoracic Society recommend a 7-day therapeutic course for VABP based on the balance of no negative impact on all-cause mortality, less resistance emergence, and fewer antibiotic treatment days, counterbalanced with a higher relapse rate for patients whose pathogen is a nonfermenter. The bacterial burden causing an infection has a substantial impact on treatment outcome and resistance selection. We describe the baseline bronchoalveolar lavage (BAL) fluid burden of organisms in suspected VABP patients screened for inclusion in a clinical trial. We measured the urea concentrations in plasma and BAL fluid to provide an index of the dilution of the bacterial and drug concentrations in the lung epithelial lining fluid introduced by the BAL procedure. We were then able to calculate the true bacterial burden as the diluted colony count times the dilution factor. The median dilution factor was 28.7, with the interquartile range (IQR) being 11.9 to 53.2. Median dilution factor-corrected colony counts were 6.18 log10(CFU/ml) [IQR, 5.43 to 6.46 log10(CFU/ml)]. In a subset of patients, repeat BAL on day 5 showed a good stability of the dilution factor. We previously showed that large bacterial burdens reduce or stop bacterial killing by granulocytes. (This study has been registered at ClinicalTrials.gov under registration no. NCT01570192.).


Assuntos
Técnicas Bacteriológicas/métodos , Líquido da Lavagem Broncoalveolar/microbiologia , Pneumonia Bacteriana/microbiologia , Pneumonia Associada à Ventilação Mecânica/microbiologia , Ureia/análise , Carga Bacteriana , Humanos , Pneumonia Bacteriana/tratamento farmacológico , Pneumonia Associada à Ventilação Mecânica/tratamento farmacológico , Ureia/sangue
15.
J Sports Sci ; 36(24): 2771-2777, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29745299

RESUMO

Analysis of netball has received scant attention in the literature and there is little understanding of the dynamics of netball game-play. This study aimed to analyse team and seasonal performance indicator (dis)similarity in the ANZ Championship (netball). Total season values for nine performance indicators were analysed for the ten ANZ Championship teams from 2009 to 2016. The data were analysed using a multivariate, distance-based, approach. Specifically, non-metric multidimensional scaling was used to examine seasonal and team (dis)similarity. After declining from 2009, shooting percentage, goal assists, centre pass receives, penalties and turnovers began to rise from 2011. Both penalties and turnovers declined from 2015, in addition to attempts at goal. The two-dimensional multivariate ordination plot showed relative similarity between each team and season over the observational period, suggesting stagnant game-play dynamics. Further, despite idiosyncratic seasonal profiles, teams generally followed similar directional progression across the ordination surface. Despite being observed in other team invasion sports, league-wide synchronous evolutionary tendencies were not observed within the ANZ Championships between the 2006 to 2016 seasons. However, certain teams did display seasonal fluctuation in their observed multivariate profile, with these seasonal idiosyncrasies being discussed relative to coaching and playing roster changes specific to the analysed team.


Assuntos
Desempenho Atlético , Basquetebol/estatística & dados numéricos , Comportamento Competitivo , Austrália , Humanos , Nova Zelândia , Estações do Ano
16.
J Strength Cond Res ; 32(10): 2838-2845, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30113913

RESUMO

Brooks, ER, Benson, AC, and Bruce, LM. Novel technologies found to be valid and reliable for the measurement of vertical jump height with jump-and-reach testing. J Strength Cond Res 32(10): 2838-2845, 2018-Vertical jump testing is used by coaches and athletes across many sports and disciplines to assess lower-body power and neuromuscular fatigue. A range of devices are available to measure jump height, with recent innovations attempting to improve portability, usability, and accessibility. New devices should be evaluated for their effectiveness and dependability in specific tests before being adopted. The purpose of this study was to assess the validity and reliability of 2 novel measurement devices for jump height testing with a jump-and-reach protocol. Twenty-six healthy, active adults participated during 2 testing occasions. A wearable inertial measurement unit (VERT) and a smart device application (My Jump 2) were compared with established measures (force platform and jump-and-reach apparatus [Yardstick]). Correlations between the VERT and force platform were r = 0.95 (90% confidence interval [CI]: 0.93-0.97), and r = 0.93 (90% CI: 0.90-0.95) for the Yardstick. Correlations between the My Jump 2 app and force platform were r = 0.98 (90% CI: 0.97-0.99), and r = 0.94 (90% CI: 0.92-0.96) for the Yardstick. Reliability, measured as intraclass correlation coefficient (ICC), was 0.91 (90% CI: 0.87-0.94) for the VERT, and 0.97 (90% CI: 0.96-0.98) for the My Jump 2 app. Intrarater reliability for the My Jump 2 app was ICC = 0.99 (90% CI: 0.99-0.99). The VERT and the My Jump 2 app have both shown acceptable validity and reliability compared with both the force platform and Yardstick. However, practitioners should consider which measurement device/s to use based on the acceptable level of potential error for their population and testing objectives.


Assuntos
Desempenho Atlético , Teste de Esforço/instrumentação , Adulto , Atletas , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Adulto Jovem
17.
Ann Allergy Asthma Immunol ; 119(2): 146-152.e2, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28634021

RESUMO

BACKGROUND: Acute infections with Mycoplasma pneumoniae (Mp) have been associated with worsening asthma in children. Mp can be present in the respiratory tract for extended periods; it is unknown whether the long-term persistence of Mp in the respiratory tract affects long-term asthma control. OBJECTIVE: To determine the effect of Mp on asthma control. METHODS: We enrolled 31 pediatric subjects 3 to 10 years of age with persistent asthma who completed up to 8 visits over a 24-month period. We detected Mp by antigen capture and polymerase chain reaction. Primary outcome measurements included symptom scores, quality of life, medication scores, oral corticosteroid use, health care usage, school absences, and exhaled breath condensate pH. RESULTS: Low levels of Mp community-acquired respiratory distress syndrome toxin were detected in 20 subjects (64.5%) at enrollment. Subjects with Mp positivity at a given visit had a .579 probability of remaining Mp positive at the subsequent visit, whereas those with Mp negativity had a .348 probability of becoming Mp positive at the following visit. The incidence of Mp overall was higher in the spring and summer months. Overall, we found no significant relation between the detection of Mp and worse outcome measurements at the same visit or at subsequent visits. CONCLUSION: The long-term persistence of Mp in the respiratory tract is common in children with asthma. However, the detection of Mp was not associated significantly with worse asthma symptoms, quality of life, health care usage, school absences, or exhaled breath condensate pH in this pediatric asthma cohort.


Assuntos
Asma/imunologia , Asma/microbiologia , Nível de Saúde , Mycoplasma pneumoniae/isolamento & purificação , Qualidade de Vida , Sistema Respiratório/microbiologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Mycoplasma pneumoniae/imunologia , Pneumonia por Mycoplasma/imunologia , Pneumonia por Mycoplasma/microbiologia , Estudos Prospectivos , Estações do Ano
18.
Artigo em Inglês | MEDLINE | ID: mdl-28238832

RESUMO

Commercial fisheries bycatch is a considerable threat to elasmobranch population recovery, and techniques to mitigate sub-lethal consequences can be improved with data on the energetic, physiological, and behavioral response of individuals to capture. This study sought to estimate the effects of simulated longline capture on the behavior, energy use, and physiological stress of juvenile lemon sharks (Negaprion brevirostris). Captive sharks equipped with acceleration biologgers were subjected to 1h of simulated longline capture. Swimming behaviors were identified from acceleration data using a machine-learning algorithm, energetic costs were estimated using accelerometer-calibrated relationships and respirometry, and physiological stress was quantified with point-of-care blood analyzers. During capture, sharks exhibited nine-fold increases in the frequency of burst swimming, 98% reductions in resting, and swam as often as unrestrained sharks. Aerobic metabolic rates during capture were 8% higher than for unrestrained sharks, and accounted for a 57.7% increase in activity costs when excess post-exercise oxygen consumption was included. Lastly, sharks exhibited significant increases in blood lactate and glucose, but no change in blood pH after 1h of capture. Therefore, these results provide preliminary insight into the behavioral and energetic responses of sharks to capture, and have implications for mitigating sub-lethal consequences of capture for sharks as commercial longline bycatch.


Assuntos
Restrição Física , Tubarões/fisiologia , Estresse Fisiológico , Animais , Pesqueiros , Consumo de Oxigênio
19.
BMC Evol Biol ; 16(1): 126, 2016 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-27296413

RESUMO

BACKGROUND: All vertebrates initially feed their offspring using yolk reserves. In some live-bearing species these yolk reserves may be supplemented with extra nutrition via a placenta. Sharks belonging to the Carcharhinidae family are all live-bearing, and with the exception of the tiger shark (Galeocerdo cuvier), develop placental connections after exhausting yolk reserves. Phylogenetic relationships suggest the lack of placenta in tiger sharks is due to secondary loss. This represents a dramatic shift in reproductive strategy, and is likely to have left a molecular footprint of positive selection within the genome. RESULTS: We sequenced the transcriptome of the tiger shark and eight other live-bearing shark species. From this data we constructed a time-calibrated phylogenetic tree estimating the tiger shark lineage diverged from the placental carcharhinids approximately 94 million years ago. Along the tiger shark lineage, we identified five genes exhibiting a signature of positive selection. Four of these genes have functions likely associated with brain development (YWHAE and ARL6IP5) and sexual reproduction (VAMP4 and TCTEX1D2). CONCLUSIONS: Our results indicate the loss of placenta in tiger sharks may be associated with subsequent adaptive changes in brain development and sperm production.


Assuntos
Placenta , Seleção Genética , Tubarões/fisiologia , Animais , Sequência de Bases , Feminino , Masculino , Filogenia , Gravidez , Reprodução , Tubarões/genética , Transcriptoma
20.
Environ Toxicol ; 29(8): 908-15, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23047665

RESUMO

Increases in asthma worldwide have been associated epidemiologically with expanding urban air pollution. The mechanistic relationship between airway hyper-responsiveness, inflammation, and ambient airborne triggers remains ambiguous. Acrolein, a ubiquitous aldehyde pollutant, is a product of incomplete combustion reactions. Acrolein is abundant in cigarette smoke, effluent from industrial smokestacks, diesel exhaust, and even hot oil cooking vapors. Acrolein is a potent airway irritant and can induce airway hyper-responsiveness and inflammation in the lungs of animal models. In the present study, we utilized the mast cell analog, RBL-2H3, to interrogate the responses of cells relevant to airway inflammation and allergic responses as a model for the induction of asthma-like conditions upon exposure to acrolein. We hypothesized that acrolein would induce oxidative stress and degranulation in airway mast cells. Our results indicate that acrolein at 1 ppm initiated degranulation and promoted the generation of reactive oxygen species (ROS). Introduction of antioxidants to the system significantly reduced both ROS generation and degranulation. At higher levels of exposure (above 100 ppm), RBL-2H3 cells displayed signs of severe toxicity. This experimental data indicates acrolein can induce an allergic inflammation in mast cell lines, and the initiation of degranulation was moderated by the application of antioxidants.


Assuntos
Acroleína/toxicidade , Poluentes Atmosféricos/toxicidade , Degranulação Celular/efeitos dos fármacos , Mastócitos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Citocinas/metabolismo , Mastócitos/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo
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