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1.
Environ Geochem Health ; 46(7): 242, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849707

RESUMO

Emerging from the shadow of the COVID-19 pandemic, it is time to ground ourselves and retrospectively assess the recent achievements of SEGH over the past years. This editorial serves as a comprehensive report on the progress made in comparison to the aspirations and goals set by the society's board in 2019 (Watts et al., Environ Geochem Health 42:343-347, 2019) (Fig. 1) and reflects on the state of the SEGH community as it reached its 50th anniversary at the close of 2021 (Watts et al. Environ Geochem Health 45:1165-1171, 2023). The focus lies on how the SEGH community navigated through the extraordinary challenges posed by the COVID-19 pandemic since early 2020, and to what extent the 2023 targets have been met.


Assuntos
COVID-19 , COVID-19/epidemiologia , Humanos , Saúde Ambiental , Sociedades Científicas , Estudos Retrospectivos , SARS-CoV-2
2.
Eur J Sport Sci ; 23(11): 2232-2239, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37331347

RESUMO

OBJECTIVES: Elite rugby union players face numerous physiological and psychological stressors which can increase upper respiratory and gastrointestinal illness risk, and in turn can compromise training and competitive performance. This study aimed to investigate the effect of daily prebiotic supplementation on upper respiratory symptoms, gastrointestinal symptoms, and markers of immune function in elite rugby union players. METHODS: Thirty-three elite rugby union players were randomly assigned to consume a prebiotic (2.8 g/day galactooligosaccharide) or placebo (2.8 g/day maltodextrin), daily for 168 days under double-blind conditions. Participants completed daily and weekly questionnaires for self-reported upper respiratory and gastrointestinal symptoms respectively. Blood and saliva samples were collected at 0, 84, and 168 days for assessment of plasma TNF-α and CRP, and saliva IgA respectively. RESULTS: The prebiotic group experienced a 2-day reduction in upper respiratory symptom duration (P = 0.045). Gastrointestinal symptom severity and incidence were lower in the prebiotic group compared to the placebo group (P < 0.001, P = 0.041) respectively. Salivary immunoglobulin A secretion rate was 42% greater in the prebiotic group compared to the placebo group at day 168 (P = 0.004), no differences in CRP and TNF-α were found (P > 0.05). CONCLUSION: A 168-day dietary prebiotic intervention reduced the duration of upper respiratory symptoms and reduced the incidence and severity of gastrointestinal symptoms in elite rugby union players. These findings suggest that seasonal prebiotic interventions may be beneficial for reducing illness in elite rugby union players, improving their availability to train and compete.Key pointsElite athletes are susceptible to upper respiratory symptoms and gastrointestinal symptoms which may impact upon training availability and competition performance.For the first time, this study shows that a dietary prebiotic intervention can reduce the duration of upper respiratory symptoms by 2 days in elite rugby union players.Dietary prebiotic supplementation can improve the incidence and severity of gastrointestinal symptoms experienced by elite rugby union players.Prebiotic supplementation was able to increase salivary IgA secretion after 168 days.These findings can inform practice suggesting that seasonal prebiotic use has the potential to modulate immune function and reduce illness in elite rugby union, which may improve a player's availability to train and compete.The mechanisms by which prebiotics reduce URS and GIS require further research exploration.


Assuntos
Futebol Americano , Gastroenteropatias , Humanos , Prebióticos , Autorrelato , Rugby , Fator de Necrose Tumoral alfa , Futebol Americano/fisiologia , Gastroenteropatias/prevenção & controle , Imunoglobulina A
3.
Sci Rep ; 13(1): 7575, 2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37165006

RESUMO

Nonalcoholic fatty liver disease (NAFLD) encompasses a spectrum of pathologies that includes steatosis, steatohepatitis (NASH) and fibrosis and is strongly associated with insulin resistance and type 2 diabetes. Changes in mitochondrial function are implicated in the pathogenesis of NAFLD, particularly in the transition from steatosis to NASH. Mitophagy is a mitochondrial quality control mechanism that allows for the selective removal of damaged mitochondria from the cell via the autophagy pathway. While past work demonstrated a negative association between liver fat content and rates of mitophagy, when changes in mitophagy occur during the pathogenesis of NAFLD and whether such changes contribute to the primary endpoints associated with the disease are currently poorly defined. We therefore undertook the studies described here to establish when alterations in mitophagy occur during the pathogenesis of NAFLD, as well as to determine the effects of genetic inhibition of mitophagy via conditional deletion of a key mitophagy regulator, PARKIN, on the development of steatosis, insulin resistance, inflammation and fibrosis. We find that loss of mitophagy occurs early in the pathogenesis of NAFLD and that loss of PARKIN accelerates the onset of key NAFLD disease features. These observations suggest that loss of mitochondrial quality control in response to nutritional stress may contribute to mitochondrial dysfunction and the pathogenesis of NAFLD.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Hepatopatia Gordurosa não Alcoólica , Diabetes Mellitus Tipo 2/complicações , Fibrose , Inflamação/metabolismo , Resistência à Insulina/genética , Fígado/metabolismo , Mitofagia/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Camundongos , Animais
4.
Proc Natl Acad Sci U S A ; 120(10): e2216678120, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36857346

RESUMO

Low-light imaging is challenging in regimes where low-noise detectors are not yet available. One such regime is the shortwave infrared where even the best multipixel detector arrays typically have a noise floor in excess of 100 photons per pixel per frame. We present a homodyne imaging system capable of recovering both intensity and phase images of an object from a single frame despite an illumination intensity of ≈​1 photon per pixel. We interfere this weak signal which is below the noise floor of the detector with a reference beam that is ∼​300, 000 times brighter, record the resulting interference pattern in the spatial domain on a detector array, and use Fourier techniques to extract the intensity and phase images. We believe our approach could vastly extend the range of applications for low-light imaging by accessing domains where low-noise cameras are not currently available and for which low-intensity illumination is required.

5.
Eval Program Plann ; 97: 102250, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36739745

RESUMO

Youth mental health is a major concern both in Australia and internationally. Identifying at-risk young people is a core service priority. This report describes a "Youth Social Inclusion Program" developed in Australia to assist young people identified as having social difficulties that prevent them linking into formal mental health services. This report describes the Australian service context and uses the "program explication" methodology to document: the program activities, therapeutic processes, and underpinning evidence for the benefits of this service. Program explication is a consulting method designed to assist services to identify and review implicit program logic assumptions against evaluation literature. We demonstrate the application of this method in exploring the assumptions and evidence for the Youth Social Inclusion Program, targeting outreach to socially anxious young people in Australia. The Youth Social Inclusion Program involved seven logically consistent activities. Our literature search revealed moderate evidence for the expected benefits of the activities. This practice-based design drew on several theoretical perspectives. Given that the program logic has been established, we outline a proposal for further evaluation.


Assuntos
Serviços de Saúde Mental , Saúde Mental , Humanos , Adolescente , Austrália , Avaliação de Programas e Projetos de Saúde , Lógica
6.
Environ Geochem Health ; 45(4): 1165-1171, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35044549

RESUMO

When the SEGH international board released a short editorial paper back in 2019, we described an aim to increase the membership offering, whilst improving the diversity of input regionally, by scientific discipline and to ensure greater and more regular contact across the regions from 2020 onwards. Wider aspirations described in 2019 (Watts et al. 2019) are discussed within this short communication at the end of 2021 to evaluate progress made. In particular, how the SEGH community adapted to the unprecedented circumstances that have challenged each and every one of us throughout the COVID-19 pandemic since early 2020 and are likely to influence our activities for the foreseeable future.


Assuntos
Saúde Ambiental , Ciência Ambiental , Sociedades , Humanos , COVID-19/epidemiologia , Pandemias
7.
J Dent Res ; 101(8): 898-904, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35264049

RESUMO

This retrospective analysis of longitudinal data was developed to determine which types, combinations, and intensities of topical fluorides more effectively prevent new caries-related restorations and extractions in high caries risk adults. We included data from October 1, 2008, through June 30, 2018, from electronic dental and medical records and pharmacy database from the US Department of Veterans Affairs. Veterans who were eligible for continuing and comprehensive care, met the criteria of high caries risk (received 2 or more caries-related restorations within a 365-d period), and had 3 y of follow-up were included. Multivariable logistic regression models estimated the odds of caries-related treatment during the 1-y observation period, controlling for age, gender, race and ethnicity, illness burden (Selim comorbidity index), use of prescription medications, attendance at dental prophylaxis appointments, number of caries-related restorations during the index year, and time between first and last caries-related restoration during the index year. The study sample included 68,757 veterans, who were primarily male (91.5%), were White (73.6%), had a mean age of 59.2 ± 13.5 y, and had significant medical comorbidity as measured by the Selim index (3.7 ± 2.4 physical and 1.3 ± 1.2 mental diagnoses). They had 10.8 ± 6.3 prescription VA drug classes, took 0.6 ± 0.8 strong anticholinergic medications, and had 3.9 ± 2.6 teeth restored due to caries during the index year. Adjusted multivariable logistic regression models showed veterans who received a varnish or gel/rinse fluoride intervention versus no fluoride had an approximately 29% decreased odds of receiving caries-related treatment during the observation period (gel/rinse adjusted odds ratio [AOR] = 0.72; 95% confidence interval [CI], 0.67-0.76; varnish AOR = 0.71; 95% CI, 0.67-0.75). The receipt of a varnish and gel/rinse did not demonstrate statistically better odds than each intervention alone (AOR = 0.69; 95% CI, 0.64-0.75). A dose-response effect was observed. Two-plus applications of varnish versus none (AOR = 0.73; 95% CI, 0.69-0.77) and 2-plus applications of gel/rinse versus none (AOR = 0.71; 95% CI, 0.67-0.75) were more effective than 1 application of either modality versus none.


Assuntos
Cárie Dentária , Fluoretos Tópicos , Adulto , Idoso , Cariostáticos/uso terapêutico , Cárie Dentária/epidemiologia , Cárie Dentária/prevenção & controle , Suscetibilidade à Cárie Dentária , Fluoretos/uso terapêutico , Fluoretos Tópicos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
8.
Med Vet Entomol ; 35(4): 646-651, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34013620

RESUMO

Mosquito Magnet® traps, deployed in widespread parts of England as part of nationwide mosquito surveillance projects, also caught blackflies. As many as 1242 blackflies were caught in a trapping session lasting 4 days. Principal among the species caught were Simulium equinum, Simulium lineatum and Simulium ornatum s.l. As S. ornatum s.l. is a vector that transmits Onchocerca linealis to cattle and S. equinum is responsible for dermatitis ('sweet itch') in cattle and horses, it is suggested that Mosquito Magnet® traps could be used to monitor and partially control these pests, as well as nuisance anthropophilic blackflies such as Simulium posticatum that can cause simuliidosis in southern England.


Assuntos
Doenças dos Bovinos , Culicidae , Doenças dos Cavalos , Oncocercose , Simuliidae , Animais , Bovinos , Vetores de Doenças , Cavalos , Mosquitos Vetores , Onchocerca , Oncocercose/veterinária
9.
J Agric Food Chem ; 68(37): 10167-10173, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32786844

RESUMO

For pesticide registration a post application assessment is made on the safety of any residue remaining in the edible portion of the treated crop. This assessment does not typically consider the bioaccessibility of pesticide residues. The effects of this on potential exposure to incurred difenoconazole residues passing through the human gastrointestinal tract were studied, including the impact of commodity processing. It has previously been demonstrated that solvent extraction methods have the potential to overestimate the bioaccessible fraction, so in vitro simulated gut systems may offer a better approach to determine residue bioaccessibility to refine the risk assessment process. The bioaccessibility of difenoconazole residues associated with processed rice samples was assessed using in vitro intestinal extraction and colonic fermentation methods. The mean bioaccessibility following intestinal digestion was 33.3% with a range from 13% to 70.6%. Quantification of the colonic bioaccessible fraction was not possible due to compound metabolism. Mechanical processing methods generally increased the residue bioaccessibility, while chemical methods resulted in a decrease. Both mechanical and chemical processing methods reduced the total difenoconazole residue level by ca. 50%.


Assuntos
Dioxolanos/química , Manipulação de Alimentos/métodos , Oryza/química , Resíduos de Praguicidas/química , Triazóis/química , Disponibilidade Biológica , Digestão , Dioxolanos/metabolismo , Trato Gastrointestinal/metabolismo , Humanos , Oryza/metabolismo , Resíduos de Praguicidas/metabolismo , Medição de Risco , Sementes/química , Sementes/metabolismo , Triazóis/metabolismo
11.
J Appl Microbiol ; 128(4): 934-949, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31446668

RESUMO

AIMS: The concept of using specific dietary components to selectively modulate the gut microbiota to confer a health benefit, defined as prebiotics, originated in 1995. In 2018, a group of scientists met at the International Scientific Association for Probiotics and Prebiotics annual meeting in Singapore to discuss advances in the prebiotic field, focussing on issues affecting functionality, research methodology and geographical differences. METHODS AND RESULTS: The discussion ranged from examining scientific literature supporting the efficacy of established prebiotics, to the prospects for establishing health benefits associated with novel compounds, isolated from different sources. CONCLUSIONS: While many promising candidate prebiotics from across the globe have been highlighted in preliminary research, there are a limited number with both demonstrated mechanism of action and defined health benefits as required to meet the prebiotic definition. Prebiotics are part of a food industry with increasing market sales, yet there are great disparities in regulations in different countries. Identification and commercialization of new prebiotics with unique health benefits means that regulation must improve and remain up-to-date so as not to risk stifling research with potential health benefits for humans and other animals. SIGNIFICANCE AND IMPACT OF STUDY: This summary of the workshop discussions indicates potential avenues for expanding the range of prebiotic substrates, delivery methods to enhance health benefits for the end consumer and guidance to better elucidate their activities in human studies.


Assuntos
Pesquisa Biomédica/normas , Congressos como Assunto , Indústria Alimentícia/normas , Prebióticos/normas , Animais , Dieta , Indústria Alimentícia/legislação & jurisprudência , Microbioma Gastrointestinal , Humanos , Prebióticos/administração & dosagem , Prebióticos/análise , Singapura , Sociedades Científicas
12.
Rev. bras. farmacogn ; 29(4): 464-469, July-Aug. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1042272

RESUMO

Abstract Biflorin (6,9-dimethyl-3-(4-methylpent-3-en-1-yl) benzo[de]chromene-7,8-dione) is a promising substance that has been increasingly studied in the past decades due to its diverse pharmacological properties (i.e. antitumor, antioxidant, antiinflamatory, antimicrobial activity etc.). Aiming the comprehension of its antitumoral activity we investigated the cell proliferation and cytotoxicity habilities of biflorin against mice splenocytes Balb/c. Biflorin was able to stimulate mice splenocytes Balb/c in 48 h of incubation at a concentration of 20.2 µM. Its immunostimulation promoted the production of cytokines such as: TNF-α, IFN-γ, IL-2, IL-6 and IL-17, inducing the immune profile toward a Th1 response. Moreover, an original method which led to an excellent yield with less processing time compared to the methods described in the literature was developed to obtain biflorin, from sawdust of Capraria biflora L., Scrophulariaceae. This method shows a great potential of increasing the production of this pharmacological active compound.

13.
Psychopharmacology (Berl) ; 236(5): 1459-1470, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30955108

RESUMO

RATIONALE: The gut-brain axis includes bidirectional communication between intestinal microbiota and the central nervous system. Bifidobacterium and Lactobacillus spp. have been implicated in psychological health, such as depression, through various pathways (e.g. inflammation). Research needs a better understanding of direct and indirect effects through examination of psychological factors that make people susceptible to, or offer protection against, depression. OBJECTIVE: This study investigated the relationships between gut microbiota, inflammation and psychological risk and resilience factors for depression. METHODS: Forty participants (13 m/27 f) recruited from the general population completed self-report questionnaires for depression, self-judgement, over-identification and affective and cognitive empathy. Faecal and blood samples were taken to assay microbiota (Bifidobacterium; Lactobacillus spp.) and pro-inflammatory molecules (C-reactive protein, CRP and interleukin-6, IL-6), respectively. RESULTS: Hierarchical regression analyses (controlling for sex, age and the shared variance of risk and resilience factors) showed that (i) cognitive depression was significantly predicted by negative self-judgement and reduced cognitive empathy; (ii) abundance of Lactobacillus spp. was directly related to positive self-judgement but only indirectly to cognitive depression and lower affective empathy (both through self-judgement); and (iii) CRP was the strongest predictor of reduced cognitive empathy, with suppression effects seen for age (negative) and IL-6 (positive) after controlling for CRP. CONCLUSIONS: Findings suggest that lactobacilli and inflammation may be differentially associated with mood disorder via brain mechanisms underpinning self-judgement and cognitive empathy, respectively. Further trials investigating interventions to increase Lactobacillus spp. in depression would benefit from direct measures of self-judgement and affective empathic distress, whilst those that aim to reduce inflammation should investigate cognitive empathy.


Assuntos
Encéfalo/metabolismo , Depressão/metabolismo , Empatia/fisiologia , Microbioma Gastrointestinal/fisiologia , Mediadores da Inflamação/metabolismo , Julgamento/fisiologia , Adulto , Depressão/psicologia , Feminino , Humanos , Inflamação/metabolismo , Lactobacillus/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
Osteoarthritis Cartilage ; 27(2): 294-303, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30448533

RESUMO

OBJECTIVE: To characterize local disease progression of the medial meniscus transection (MMT) model of post-traumatic osteoarthritis (OA) at the molecular level, in order to establish a baseline for therapeutic testing at the preclinical stage. DESIGN: Weight-matched male Lewis rats underwent MMT or sham surgery on the left limb with the right leg as contralateral control. At 1 and 3 weeks post-surgery, tissues were harvested from different areas of the articular cartilage (medial and lateral tibial plateaus, and medial osteophyte region) and synovium (medial and lateral), and analyzed separately. RNA was extracted and used for microarray (RT-PCR) analysis. RESULTS: Gene expression changes due to surgery were isolated to the medial side of the joint. Gene changes in chondrocyte phenotype of the medial tibial plateau cartilage preceded changes in tissue composition genes. Differences in inflammatory markers were only observed at the osteophyte region at 3 weeks post-surgery. There was surgical noise in the synovium at week 1, which dissipated at week 3. At this later timepoint, meniscal instability resulted in elevated expression of matrix degradation proteins and osteogenic markers in the synovium and cartilage. CONCLUSION: These results suggest feedback interactions between joint tissues during disease progression. Regional tissue expression differences found in MMT joints indicated similar pathophysiology to human OA, and provided novel insights about this degeneration model. The examination of gene expression at a localized level in multiple tissues provides a well-characterized baseline to evaluate mechanistic effects of potential therapeutic agents on OA disease progression in the MMT model.


Assuntos
Artrite Experimental/genética , Osteoartrite/genética , Lesões do Menisco Tibial/genética , Animais , Artrite Experimental/etiologia , Artrite Experimental/metabolismo , Cartilagem Articular/metabolismo , Condrócitos/metabolismo , Análise por Conglomerados , Colágeno Tipo II/metabolismo , Progressão da Doença , Expressão Gênica , Masculino , Metaloproteinase 13 da Matriz/metabolismo , Osteoartrite/etiologia , Osteoartrite/metabolismo , Osteopontina/metabolismo , Ratos Endogâmicos Lew , Membrana Sinovial/metabolismo , Tíbia/metabolismo , Lesões do Menisco Tibial/complicações , Lesões do Menisco Tibial/metabolismo , Transcriptoma
15.
Rev. bras. farmacogn ; 28(4): 425-432, July-Aug. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-958882

RESUMO

Abstract Condensed tannins have been used for many years in folk medicine to treat gastric problems. The mechanism of action that explains why tannins improve gastritis symptoms is based on their ability to chelate metals, antioxidant activity, and their complexation power with other molecules. Even though these uses are well-known, the requirements to become an herbal medicine are much more complex. Herein, we analyzed Stryphnodendron rotundifolium Mart., Fabaceae, extract using MALDI for tannin characterization and carried out a fluorescence-imaging study to prove the gastroprotective effects of tannins as coating agents. Through these methods we show that condensed tannins form a gastroprotective layer. Moreover, we revise and discuss other possible mechanisms of action for phenolic-rich plant extracts and their potential in the development of herbal medicines to treat ulcers and gastritis.

16.
Thorax ; 73(8): 713-722, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29680821

RESUMO

BACKGROUND: Previous models of Hospital at Home (HAH) for COPD exacerbation (ECOPD) were limited by the lack of a reliable prognostic score to guide patient selection. Approximately 50% of hospitalised patients have a low mortality risk by DECAF, thus are potentially suitable. METHODS: In a non-inferiority randomised controlled trial, 118 patients admitted with a low-risk ECOPD (DECAF 0 or 1) were recruited to HAH or usual care (UC). The primary outcome was health and social costs at 90 days. RESULTS: Mean 90-day costs were £1016 lower in HAH, but the one-sided 95% CI crossed the non-inferiority limit of £150 (CI -2343 to 312). Savings were primarily due to reduced hospital bed days: HAH=1 (IQR 1-7), UC=5 (IQR 2-12) (P=0.001). Length of stay during the index admission in UC was only 3 days, which was 2 days shorter than expected. Based on quality-adjusted life years, the probability of HAH being cost-effective was 90%. There was one death within 90 days in each arm, readmission rates were similar and 90% of patients preferred HAH for subsequent ECOPD. CONCLUSION: HAH selected by low-risk DECAF score was safe, clinically effective, cost-effective, and preferred by most patients. Compared with earlier models, selection is simpler and approximately twice as many patients are eligible. The introduction of DECAF was associated with a fall in UC length of stay without adverse outcome, supporting use of DECAF to direct early discharge. TRIAL REGISTRATION NUMBER: Registered prospectively ISRCTN29082260.


Assuntos
Serviços de Assistência Domiciliar/economia , Doença Pulmonar Obstrutiva Crônica/terapia , Idoso , Análise Custo-Benefício , Feminino , Custos Hospitalares , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Satisfação do Paciente , Seleção de Pacientes , Prognóstico , Estudos Prospectivos , Fatores de Risco
17.
Proc Biol Sci ; 285(1871)2018 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-29367389

RESUMO

The mating behaviour of many mosquito species is mediated essentially by sound: males follow and mate with a female mid-flight by detecting and tracking the whine of her flight-tones. The stereotypical rapid frequency modulation (RFM) male behaviour, initiated in response to the detection of the female's flight-tones, has provided a means of investigating these auditory mechanisms while males are free-flying. Mosquitoes hear with their antennae, which vibrate to near-field acoustic excitation. The antennae generate nonlinear vibrations (distortion products, DPs) at frequencies that are equal to the difference between the two simultaneously presented tones, e.g. the male and female flight-tones, which are detected by mechanoreceptors in the auditory Johnston's organ (JO) at the base of the antenna. Recent studies indicated the male mosquito's JO is tuned not to the female flight-tone, but to the frequency difference between the male and female flight-tones. To test the hypothesis that mosquitoes detect this frequency difference, Culex quinquefasciatus males were presented simultaneously with a female flight-tone and a masking tone, which should suppress the male's RFM response to sound. The free-flight behavioural and in vivo electrophysiological experiments revealed that acoustic masking suppresses the RFM response to the female's flight-tones by attenuating the DPs generated in the nonlinear vibration of the antennae. These findings provide direct evidence in support of the hypothesis that male mosquitoes detect females when both are in flight through difference tones generated in the vibrations of their antennae owing to the interaction between their own flight-tones and those of a female.


Assuntos
Percepção Auditiva , Culex/fisiologia , Comportamento Sexual Animal , Estimulação Acústica , Animais , Feminino , Masculino , Mecanorreceptores/fisiologia , Vibração
19.
J Appl Ichthyol ; 33(3): 317-322, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28626278

RESUMO

Natural mortality of Atlantic sturgeon (Acipenser oxyrinchus) has been determined to be low (M = 0.07). Reported herein is the mortality by beach stranding of 11 Atlantic sturgeon in Scot's Bay, part of the inner Bay of Fundy in Nova Scotia, Canada on 22 June 2014. Genetic analyses, histological analysis and age determination were performed to determine origin, maturity stage and age of the stranded Atlantic sturgeon. Microsatellite and mitochondrial DNA analyses indicated that four of the Atlantic sturgeon (2 males and 2 females) were from the Saint John River, NB population, which was designated as threatened by the Committee on the Status of Endangered Wildlife in Canada. Seven Atlantic sturgeon (1 male, 5 females, 1 unknown) were from the Kennebec River, Maine population, that was listed as threatened under the Endangered Species Act in the U. S. Ageing of A. oxyrinchus by pectoral fin spine analysis determined that the mean age of the individuals from the Saint John River ( [Formula: see text] years, sd = 5.0) and the Kennebec River ( [Formula: see text] years, sd = 3.5) were not significantly different. This is the first report of a stranding event of Atlantic sturgeon, and describes a source of natural mortality affecting populations of concern in both Canada and the U. S.

20.
JAMA ; 317(21): 2177-2186, 2017 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-28528348

RESUMO

Importance: Outcomes after exacerbations of chronic obstructive pulmonary disease (COPD) requiring acute noninvasive ventilation (NIV) are poor and there are few treatments to prevent hospital readmission and death. Objective: To investigate the effect of home NIV plus oxygen on time to readmission or death in patients with persistent hypercapnia after an acute COPD exacerbation. Design, Setting, and Participants: A randomized clinical trial of patients with persistent hypercapnia (Paco2 >53 mm Hg) 2 weeks to 4 weeks after resolution of respiratory acidemia, who were recruited from 13 UK centers between 2010 and 2015. Exclusion criteria included obesity (body mass index [BMI] >35), obstructive sleep apnea syndrome, or other causes of respiratory failure. Of 2021 patients screened, 124 were eligible. Interventions: There were 59 patients randomized to home oxygen alone (median oxygen flow rate, 1.0 L/min [interquartile range {IQR}, 0.5-2.0 L/min]) and 57 patients to home oxygen plus home NIV (median oxygen flow rate, 1.0 L/min [IQR, 0.5-1.5 L/min]). The median home ventilator settings were an inspiratory positive airway pressure of 24 (IQR, 22-26) cm H2O, an expiratory positive airway pressure of 4 (IQR, 4-5) cm H2O, and a backup rate of 14 (IQR, 14-16) breaths/minute. Main Outcomes and Measures: Time to readmission or death within 12 months adjusted for the number of previous COPD admissions, previous use of long-term oxygen, age, and BMI. Results: A total of 116 patients (mean [SD] age of 67 [10] years, 53% female, mean BMI of 21.6 [IQR, 18.2-26.1], mean [SD] forced expiratory volume in the first second of expiration of 0.6 L [0.2 L], and mean [SD] Paco2 while breathing room air of 59 [7] mm Hg) were randomized. Sixty-four patients (28 in home oxygen alone and 36 in home oxygen plus home NIV) completed the 12-month study period. The median time to readmission or death was 4.3 months (IQR, 1.3-13.8 months) in the home oxygen plus home NIV group vs 1.4 months (IQR, 0.5-3.9 months) in the home oxygen alone group, adjusted hazard ratio of 0.49 (95% CI, 0.31-0.77; P = .002). The 12-month risk of readmission or death was 63.4% in the home oxygen plus home NIV group vs 80.4% in the home oxygen alone group, absolute risk reduction of 17.0% (95% CI, 0.1%-34.0%). At 12 months, 16 patients had died in the home oxygen plus home NIV group vs 19 in the home oxygen alone group. Conclusions and Relevance: Among patients with persistent hypercapnia following an acute exacerbation of COPD, adding home noninvasive ventilation to home oxygen therapy prolonged the time to readmission or death within 12 months. Trial Registration: clinicaltrials.gov Identifier: NCT00990132.


Assuntos
Ventilação não Invasiva , Oxigenoterapia , Readmissão do Paciente/estatística & dados numéricos , Doença Pulmonar Obstrutiva Crônica/terapia , Idoso , Terapia Combinada , Feminino , Volume Expiratório Forçado , Serviços de Assistência Domiciliar , Humanos , Hipercapnia/etiologia , Hipercapnia/terapia , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/mortalidade , Qualidade de Vida , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/terapia , Risco , Fatores de Tempo
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