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1.
Nature ; 583(7815): 211-214, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32641814

RESUMO

The discovery of a radioactively powered kilonova associated with the binary neutron-star merger GW170817 remains the only confirmed electromagnetic counterpart to a gravitational-wave event1,2. Observations of the late-time electromagnetic emission, however, do not agree with the expectations from standard neutron-star merger models. Although the large measured ejecta mass3,4 could be explained by a progenitor system that is asymmetric in terms of the stellar component masses (that is, with a mass ratio q of 0.7 to 0.8)5, the known Galactic population of merging double neutron-star systems (that is, those that will coalesce within billions of years or less) has until now consisted only of nearly equal-mass (q > 0.9) binaries6. The pulsar PSR J1913+1102 is a double system in a five-hour, low-eccentricity (0.09) orbit, with an orbital separation of 1.8 solar radii7, and the two neutron stars are predicted to coalesce in [Formula: see text] million years owing to gravitational-wave emission. Here we report that the masses of the pulsar and the companion neutron star, as measured by a dedicated pulsar timing campaign, are 1.62 ± 0.03 and 1.27 ± 0.03 solar masses, respectively. With a measured mass ratio of q = 0.78 ± 0.03, this is the most asymmetric merging system reported so far. On the basis of this detection, our population synthesis analysis implies that such asymmetric binaries represent between 2 and 30 per cent (90 per cent confidence) of the total population of merging binaries. The coalescence of a member of this population offers a possible explanation for the anomalous properties of GW170817, including the observed kilonova emission from that event.

2.
J Asthma ; 61(8): 876-882, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38265280

RESUMO

OBJECTIVE: Education and self-management plans enhance parents' self-efficacy in managing their child's asthma symptoms. By understanding how parents recognize and interpret acute asthma symptoms, we can compile patient information using terms that are familiar to parents. METHOD: Semi-structured interviews were carried out with 27 parents of children with asthma aged 2-12 years. The interviewees were selected from three groups: parents of children admitted for acute asthma, parents of children receiving outpatient asthma care, and parents who had access to a self-management plan. Parents were invited to report symptoms they would associate with acute asthma. Subsequently, parents were queried about their recognition of symptoms from a predefined list and asked to explain how they would assess these symptoms in case their child would experience an attack of acute asthma. RESULTS: The most frequently reported symptoms for acute asthma were shortness of breath (77.8%) and coughing (63%). Other signs such as retractions, nasal flaring, and wheezing were reported by less than 25% of the parents. All parents recognized shortness of breath, wheezing and gasping for breath from a predefined list of medical terms. Retractions and nasal flaring were recognized by 81.5% and 66.7% of the parents, respectively. Recognizing the medical terms did not necessarily translate into parents being able to explain how to assess these symptoms. CONCLUSION: Parents and healthcare professionals do not always speak the same language concerning symptoms of acute asthma. This may hamper timely recognition and adequate self-management, highlighting the necessity to adjust current medical information about acute asthma.


Education and self-management plans enhance parents' self-efficacy in managing their child's asthma symptoms.Parents may identify symptoms of acute asthma differently than healthcare providersInformation material about acute asthma should be adjusted to empower parents to decide when to commence treatment and when to seek medical attention.


Assuntos
Asma , Pais , Humanos , Asma/diagnóstico , Pais/psicologia , Pré-Escolar , Criança , Masculino , Feminino , Doença Aguda , Pessoal de Saúde , Idioma , Dispneia/diagnóstico , Entrevistas como Assunto , Sons Respiratórios , Adulto
3.
J Fish Biol ; 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38402692

RESUMO

Coercive mating is a sexual selection strategy that is likely to influence female cognition. Female harassment levels have been linked to altered brain gene expression patterns and brain size evolution, suggesting females may respond to coercive mating by investing energy into "outsmarting" males. However, females exposed to coercive males have decreased foraging efficiency and likely increased stress levels, suggesting their brain function might instead be impaired. While it is therefore likely that coercive mating impacts female cognitive abilities, a direct test of this idea is currently lacking. In this study, we investigate the impact of coercive mating on female spatial memory and cognitive flexibility in a species with prevalent coercive mating. We compared the performance of female porthole livebearers (Poeciliopsis gracilis), which had been previously housed alone or with a coercive male, in both a spatial food localization task and a reversal learning task. While we found that both single and paired fish exhibited high proficiency in learning both tasks, we found no differences in learning ability between females that had or had not experienced coercive mating. In addition, our study found that the presence of a coercive male had no impact on female fecundity, but did influence female mass and standard length. Several studies have assumed that the presence of males, particularly coercive males, may affect the cognitive performance of female fish. However, our study shows that for some species females adapted to coercive mating regimes may be unaffected by male presence with regards to some cognitive tasks.

4.
Nature ; 531(7593): 202-5, 2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26934226

RESUMO

Fast radio bursts are millisecond-duration astronomical radio pulses of unknown physical origin that appear to come from extragalactic distances. Previous follow-up observations have failed to find additional bursts at the same dispersion measure (that is, the integrated column density of free electrons between source and telescope) and sky position as the original detections. The apparent non-repeating nature of these bursts has led to the suggestion that they originate in cataclysmic events. Here we report observations of ten additional bursts from the direction of the fast radio burst FRB 121102. These bursts have dispersion measures and sky positions consistent with the original burst. This unambiguously identifies FRB 121102 as repeating and demonstrates that its source survives the energetic events that cause the bursts. Additionally, the bursts from FRB 121102 show a wide range of spectral shapes that appear to be predominantly intrinsic to the source and which vary on timescales of minutes or less. Although there may be multiple physical origins for the population of fast radio bursts, these repeat bursts with high dispersion measure and variable spectra specifically seen from the direction of FRB 121102 support an origin in a young, highly magnetized, extragalactic neutron star.

5.
Nature ; 505(7484): 520-4, 2014 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-24390352

RESUMO

Gravitationally bound three-body systems have been studied for hundreds of years and are common in our Galaxy. They show complex orbital interactions, which can constrain the compositions, masses and interior structures of the bodies and test theories of gravity, if sufficiently precise measurements are available. A triple system containing a radio pulsar could provide such measurements, but the only previously known such system, PSR B1620-26 (refs 7, 8; with a millisecond pulsar, a white dwarf, and a planetary-mass object in an orbit of several decades), shows only weak interactions. Here we report precision timing and multiwavelength observations of PSR J0337+1715, a millisecond pulsar in a hierarchical triple system with two other stars. Strong gravitational interactions are apparent and provide the masses of the pulsar M[Symbol: see text](1.4378(13), where M[Symbol: see text]is the solar mass and the parentheses contain the uncertainty in the final decimal places) and the two white dwarf companions (0.19751(15)M[Symbol: see text] and 0.4101(3))M[Symbol: see text], as well as the inclinations of the orbits (both about 39.2°). The unexpectedly coplanar and nearly circular orbits indicate a complex and exotic evolutionary past that differs from those of known stellar systems. The gravitational field of the outer white dwarf strongly accelerates the inner binary containing the neutron star, and the system will thus provide an ideal laboratory in which to test the strong equivalence principle of general relativity.

6.
Neuroimage ; 184: 547-554, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30243958

RESUMO

Acute stress is known to affect the way we process rewards. For example, during, or directly after stress, activity within key brain areas of the reward circuitry is reduced when a reward is presented. Generally, the effects of stress on the brain are time-dependent, changing neural and cognitive processing in the aftermath of stress to aid recovery. Such a dynamic response to stress is important for resilience on the longer term. However, relatively little is known about reward processing during the recovery phase of stress and whether this is changed in individuals at increased risk for stress-related psychopathology. Healthy male individuals (N = 40) and unaffected siblings of schizophrenia patients (N = 40) were randomized to either an acute stress task (Trier Social Stress Test) or a no-stress task. Neural responses during reward anticipation and reward feedback (monetary gain or no gain) were examined 50 min later using an fMRI monetary incentive delay task. The ventral striatum and orbitofrontal cortex (OFC) were used as predefined hypothesis-driven regions of interest. Neural responses following stress differed between controls and siblings during reward feedback (group × stress interaction OFC p = 0.003, ventral striatum p = 0.031), showing increased ventral striatum and OFC responses following stress in healthy controls only. Exploratory analyses revealed that this effect was most pronounced during hit trials (compared to when a reward was omitted), and independent of monetary value. Stress did not affect subsequent reward processing in siblings of schizophrenia patients. We found no significant differences between controls and siblings in ventral striatum and OFC responses during reward anticipation following stress. This study shows that ventral striatum and OFC responses to positive task feedback are increased in the aftermath of stress in healthy male controls, regardless of monetary value. This indicates a dynamic shift from previously reported reduced responses in the striatum and OFC to reward feedback directly after stress to increased responses to both reward and non-reward feedback during the recovery phase of stress. These increased neural responses following stress were absent in siblings of schizophrenia patients. Together, these findings indicate that stress recovery is affected in this at-risk group, particularly in responses to positive feedback following stress.


Assuntos
Antecipação Psicológica/fisiologia , Encéfalo/fisiologia , Recompensa , Esquizofrenia/fisiopatologia , Estresse Psicológico/fisiopatologia , Mapeamento Encefálico , Retroalimentação , Humanos , Imageamento por Ressonância Magnética , Masculino , Motivação , Irmãos
7.
Ultrasound Obstet Gynecol ; 54(1): 119-123, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30461093

RESUMO

OBJECTIVES: To confirm our previous observation that levator hiatal dimensions and mean echogenicity of the puborectalis muscle (MEP) are significantly different at 12 weeks' gestation in women who delivered by Cesarean section due to failure to progress compared with those who delivered vaginally. The secondary objective was to assess the association between the echogenicity of the cervix and vastus lateralis muscle and mode of delivery. METHODS: In this prospective multicenter study, 306 nulliparous women with a singleton pregnancy underwent ultrasound assessments of the pelvic floor at rest, on maximum pelvic floor muscle contraction and on maximum Valsalva maneuver, of the cervix and of the vastus lateralis muscle at 12 weeks' gestation. Dimensions of the levator hiatus, MEP and mean echogenicity of the cervix and vastus lateralis muscle were measured and compared according to mode of delivery. RESULTS: Two hundred and forty-nine women were included in the analyses. We were unable to confirm our previous finding that MEP and levator hiatal transverse diameter and area at 12 weeks' gestation are associated significantly with mode of delivery. In addition, we could not demonstrate a significant association between echogenicity of the cervix or vastus lateralis muscle and mode of delivery. Overall, MEP was a mean of 20 points lower in women in the new database as compared with the previous study, despite the use of the same ultrasound equipment. CONCLUSION: In a second, independent multicenter dataset, we were unable to confirm our previous finding that levator hiatal dimensions and MEP on pelvic floor muscle contraction are associated significantly with mode of delivery. We also found no association between echogenicity of the cervix or vastus lateralis and mode of delivery. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Colo do Útero/diagnóstico por imagem , Parto Obstétrico/tendências , Diafragma da Pelve/diagnóstico por imagem , Músculo Quadríceps/diagnóstico por imagem , Ultrassonografia/métodos , Adulto , Colo do Útero/anatomia & histologia , Colo do Útero/fisiologia , Cesárea/métodos , Feminino , Idade Gestacional , Humanos , Imageamento Tridimensional/instrumentação , Contração Muscular/fisiologia , Países Baixos/epidemiologia , Diafragma da Pelve/anatomia & histologia , Diafragma da Pelve/fisiologia , Gravidez , Estudos Prospectivos , Músculo Quadríceps/fisiologia , Manobra de Valsalva/fisiologia
8.
Water Sci Technol ; 79(4): 779-788, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30975944

RESUMO

The potential growth of buffalo grass (Stenotaphrum secundatum) and couch grass (Cynodon dactylon) on artificial floating islands (AFIs) and their ability to remove total nitrogen (TN) and total phosphorus (TP) from a simulated paper mill wastewater was studied. This was done to assess the potential of AFIs for removal of nutrients from aerated stabilization basins (ASBs) that had occasional growth of blue-green algae (BGA) to bloom levels. Small scale AFIs were prepared using polyethylene foam and planted with the grasses in 30 L of tested water. Trials were conducted in a plastic covered greenhouse over a three-month period where temperatures ranged from 15 to 44 °C. The results showed that both buffalo and couch grasses can adapt to planting in AFIs showing increases of 125% and 148% in wet weight, respectively. Nutrient uptake by buffalo grass and couch grass were found to be similar. Percentage uptakes of TP and TN from the synthetic water by the buffalo grass were 82% and 47%, whereas by couch grass, uptakes were 83% and 45%, respectively.


Assuntos
Biodegradação Ambiental , Poaceae , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Animais , Búfalos , Nitrogênio/análise , Papel , Fósforo/análise
9.
J Anim Physiol Anim Nutr (Berl) ; 102(1): 308-316, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28452197

RESUMO

The effect of exposure to different UVb compact lamps on the vitamin D status of growing bearded dragons (Pogona vitticeps) was studied. Forty-two newly hatched bearded dragons (<24 h old) were allocated to six treatment groups (n = 7 per group). Five groups were exposed to different UVb compact lamps for two hours per day, with a control group not exposed to UVb radiation. At 120 days of age, blood samples were obtained and concentrations of 25(OH)D3 , Ca, P and uric acid were determined. In addition, plasma 25(OH)D3 concentration was determined in free-living adult bearded dragons to provide a reference level. Only one treatment resulted in elevated levels of 25(OH)D3 compared to the control group (41.0 ± 12.85 vs. 2.0 ± 0.0 nmol/L). All UVb-exposed groups had low 25(OH)D3 plasma levels compared to earlier studies on captive bearded dragons as well as in comparison with the free-living adult bearded dragons (409 ± 56 nmol/L). Spectral analysis indicated that all treatment lamps emitted UVb wavelengths effective for some cutaneous vitamin D synthesis. None of these lamps, under this regime, appeared to have provided a sufficient UVb dose to enable synthesis of plasma 25(OH)D3 levels similar to those of free-living bearded dragons in their native habitat.


Assuntos
Calcifediol/sangue , Lagartos/crescimento & desenvolvimento , Raios Ultravioleta , Animais , Calcifediol/biossíntese , Feminino , Lagartos/sangue , Masculino , Pele
10.
Proc Natl Acad Sci U S A ; 111(1): E149-58, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24367106

RESUMO

Ghrelin is a peptide mainly produced by the stomach and released into circulation, affecting energy balance and growth hormone release. These effects are guided largely by the expression of the ghrelin receptor growth hormone secretagogue type 1a (GHS-R1a) in the hypothalamus and pituitary. However, GHS-R1a is expressed in other brain regions, including the hippocampus, where its activation enhances memory retention. Herein we explore the molecular mechanism underlying the action of ghrelin on hippocampal-dependent memory. Our data show that GHS-R1a is localized in the vicinity of hippocampal excitatory synapses, and that its activation increases delivery of α-amino-3-hydroxy-5-methyl-4-isoxazole propionic-type receptors (AMPARs) to synapses, producing functional modifications at excitatory synapses. Moreover, GHS-R1a activation enhances two different paradigms of long-term potentiation in the hippocampus, activates the phosphatidylinositol 3-kinase, and increases GluA1 AMPAR subunit and stargazin phosphorylation. We propose that GHS-R1a activation in the hippocampus enhances excitatory synaptic transmission and synaptic plasticity by regulating AMPAR trafficking. Our study provides insights into mechanisms that may mediate the cognition-enhancing effect of ghrelin, and suggests a possible link between the regulation of energy metabolism and learning.


Assuntos
Regulação da Expressão Gênica , Grelina/fisiologia , Hipocampo/metabolismo , Receptores de AMPA/metabolismo , Sinapses/fisiologia , Animais , Eletrofisiologia , Metabolismo Energético , Grelina/metabolismo , Aprendizagem , Potenciação de Longa Duração/fisiologia , Memória , Peptídeos/química , Fosforilação , Ratos , Transdução de Sinais , Transmissão Sináptica
11.
BJOG ; 122(7): 1022-30, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25754458

RESUMO

OBJECTIVE: To compare transvaginal prolapse repair combined with midurethral sling (MUS) versus prolapse repair only. DESIGN: Multi-centre randomised trial. SETTING: Fourteen teaching hospitals in the Netherlands. POPULATION: Women with symptomatic stage two or greater pelvic organ prolapse (POP), and subjective or objective stress urinary incontinence (SUI) without prolapse reduction. METHODS: Women were randomly assigned to undergo vaginal prolapse repair with or without MUS. Analysis was according to intention to treat. MAIN OUTCOME MEASURES: The primary outcome at 12 months' follow-up was the absence of urinary incontinence (UI) assessed with the Urogenital Distress Inventory and treatment for SUI or overactive bladder. Secondary outcomes included complications. RESULTS: One hundred and thirty-four women were analysed at 12 months' follow-up (63 in MUS and 71 in control group). More women in the MUS group reported the absence of UI and SUI; respectively 62% versus 30% UI (relative risk [RR] 2.09; 95% confidence interval [CI] 1.39-3.15) and 78% versus 39% SUI (RR 1.97; 95% CI 1.44-2.71). Fewer women underwent treatment for postoperative SUI in the MUS group (10% versus 37%; RR 0.26; 95% CI 0.11-0.59). In the control group, 12 women (17%) underwent MUS after prolapse surgery versus none in the MUS group. Severe complications were more common in the MUS group, but the difference was not statistically significant (16% versus 6%; RR 2.82; 95% CI 0.93-8.54). CONCLUSIONS: Women with prolapse and co-existing SUI are less likely to have SUI after transvaginal prolapse repair with MUS compared with prolapse repair only. However, only 17% of the women undergoing POP surgery needed additional MUS. A well-informed decision balancing risks and benefits of both strategies should be tailored to individual women.


Assuntos
Procedimentos Cirúrgicos em Ginecologia/métodos , Prolapso de Órgão Pélvico/cirurgia , Slings Suburetrais/estatística & dados numéricos , Incontinência Urinária por Estresse/cirurgia , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Países Baixos , Inquéritos e Questionários , Resultado do Tratamento , Bexiga Urinária Hiperativa/prevenção & controle
12.
Reprod Fertil Dev ; 27(2): 304-12, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24192203

RESUMO

This study investigated the endocrine background of follicle size changes during post-weaning altrenogest treatment. altrenogest-treated sows received a 20-mg dosage daily at 8.00 a.m. from Day -1 to Day 14 after weaning. On Day -1, only 3/13 altrenogest-treated sows showed LH pulses compared with 8/8 control sows (P=0.001). On Day 0, control sows showed a typical high frequency-low amplitude LH pattern, indicative for recruitment of oestrogenic follicles. In altrenogest-treated animals on Day 0, half of the sows showed high frequency-high amplitude pulses from 4-5h after weaning. In altrenogest-treated sows, average follicle size increased from 3.1±0.5 mm on Day 0 to 4.4±0.6mm on Day 5, then decreased to 3.7±0.5 mm on Day 7 and stabilised thereafter. FSH and oestradiol (E2) concentrations showed a distinct diurnal pattern; high at 7.00 a.m. and low at 3.00 p.m. E2 concentrations (7.00 a.m.) showed a 2.5-fold increase from Day -1 to Day 2, and subsequently a 2-fold decline to reach a plateau at Day 8. FSH concentrations reached maximum levels by Day 5 and slowly declined afterwards. In conclusion, once-daily administration of altrenogest starting one day before weaning delays the weaning-induced increase in LH pulses. Although FSH and follicle size increase until Day 5 after weaning, follicle E2 production already decreased from Day 2 after weaning. Post-weaning altrenogest treatment thus results in a follicular wave of follicles that lose oestrogenic competence at Day 2 after weaning, presumably related to the changed LH dynamics during altrenogest treatment.


Assuntos
Estradiol/metabolismo , Hormônio Foliculoestimulante/metabolismo , Hormônio Luteinizante/metabolismo , Tamanho do Órgão/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Sus scrofa/metabolismo , Acetato de Trembolona/análogos & derivados , Fatores Etários , Animais , Feminino , Modelos Lineares , Tamanho do Órgão/fisiologia , Folículo Ovariano/citologia , Acetato de Trembolona/administração & dosagem , Acetato de Trembolona/farmacologia
13.
Parasitol Res ; 114(4): 1631-43, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25681141

RESUMO

This study compared results obtained with five different fecal egg count reduction (FECR) calculation methods for defining resistance to ivermectin, fenbendazole, and levamisole in gastrointestinal nematodes of sheep in a temperate continental climate: FECR1 and FECR2 used pre-and posttreatment fecal egg count (FEC) means from both treated and control animals, but FECR1 used arithmetic means, whereas FECR2 used geometric means; FECR3 used arithmetic means for pre- and posttreatment FECs from treated animals only; FECR4 was calculated using only arithmetic means for posttreatment FECs from treated and control animals; and FECR5 was calculated using mean FEC estimates from a general linear mixed model. The classification of farm anthelmintic resistance (AR) status varied, depending on which FECR calculation method was used and whether a bias correction term (BCT, i.e., half the minimum detection limit) was added to the zeroes or not. Overall, agreement between all methods was higher when a BCT was used, particularly when levels of resistance were low. FECR4 showed the highest agreement with all the other FECR methods. We therefore recommend that small ruminant clinicians use the FECR4 formula with a BCT for AR determination, as this would reduce the cost of the FECRT, while still minimizing bias and allowing for comparisons between different farms. For researchers, we recommend the use of FECR1 or FECR2, as the inclusion of both pre- and posttreatment FECs and use of randomly allocated animals in treatment and control groups makes these methods mathematically more likely to estimate the true anthelmintic efficacy.


Assuntos
Anti-Helmínticos/farmacologia , Resistência a Medicamentos , Nematoides/efeitos dos fármacos , Infecções por Nematoides/veterinária , Contagem de Ovos de Parasitas/métodos , Doenças dos Ovinos/parasitologia , Animais , Clima , Fezes/parasitologia , Fenbendazol/farmacologia , Ivermectina/farmacologia , Levamisol/farmacologia , Nematoides/crescimento & desenvolvimento , Nematoides/isolamento & purificação , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/parasitologia , Contagem de Ovos de Parasitas/veterinária , Ovinos , Doenças dos Ovinos/tratamento farmacológico
14.
Zoo Biol ; 34(3): 271-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25773132

RESUMO

The central bearded dragon (Pogona vitticeps) is one of the most popular pet lizards. However, little is known regarding their nutrient requirement, or their natural diet. Therefore, the stomach contents of 14 free-roaming P. vitticeps were determined by flushing. These stomach contents were described taxonomically, and analyzed for crude protein content as well as fatty acid content and composition. Most of the dry matter intake was in the form of animal material (61%) stemming from nine arthropod orders. The most abundant were alates of the termite Drepanotermes sp., accounting for 95% of the total number of prey items and more than half of the total dry matter (DM) intake. Plant material contributed 16% of the total DM intake. The diets were high in crude protein (41-50% DM) and the total fatty acid content was 14-27% of the DM intake. The main fatty acid was C18:1n9c (51-56% of total fatty acids), and polyunsaturated fatty acids (n3 and n6) comprised 6-8% of the total fat intake. Our data suggest that P. vitticeps is an opportunistic predator, which exploits the seasonal availability of prey. Based on our data and other studies, a diet consisting of several insect species, supplemented with leafy vegetables, rich in n3 FA's, would best resemble the expected natural diet of P. vitticeps.


Assuntos
Animais Selvagens/fisiologia , Dieta/veterinária , Conteúdo Gastrointestinal , Lagartos/fisiologia , Necessidades Nutricionais , Animais , Artrópodes/metabolismo , Austrália , Proteínas Alimentares/análise , Ácidos Graxos/análise , Ácidos Graxos/química , Verduras/metabolismo
15.
Qual Life Res ; 23(6): 1733-41, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24402179

RESUMO

BACKGROUND: The Patient-Reported Outcomes Measurement Information System (PROMIS(®)) is a new, state-of-the-art assessment system for measuring patient-reported health and well-being of adults and children that has the potential to be more valid, reliable and responsive than existing PROMs. The PROMIS items can be administered in short forms or, more efficiently, through computerized adaptive testing. This paper describes the translation of 563 items from 17 PROMIS item banks (domains) for adults from the English source into Dutch-Flemish. METHODS: The translation was performed by FACITtrans using standardized methodology and approved by the PROMIS Statistical Center. The translation included four forward translations, two back-translations, three to five independent reviews (at least two Dutch, one Flemish) and pre-testing in 70 adults (age range 20-77) from the Netherlands and Flanders. RESULTS: A small number of items required separate translations for Dutch and Flemish: physical function (five items), pain behaviour (two items), pain interference (one item), social isolation (one item) and global health (one item). Challenges faced in the translation process included: scarcity or overabundance of possible translations, unclear item descriptions, constructs broader/smaller in the target language, difficulties in rank ordering items, differences in unit of measurement, irrelevant items or differences in performance of activities. By addressing these challenges, acceptable translations were obtained for all items. CONCLUSION: The methodology used and experience gained in this study can be used as an example for researchers in other countries interested in translating PROMIS. The Dutch-Flemish PROMIS items are linguistically equivalent. Short forms will soon be available for use and entire item banks are ready for cross-cultural validation in the Netherlands and Flanders.


Assuntos
Nível de Saúde , Avaliação de Resultados da Assistência ao Paciente , Qualidade de Vida , Inquéritos e Questionários/normas , Tradução , Adulto , Idoso , Bélgica , Comparação Transcultural , Feminino , Humanos , Sistemas de Informação , Masculino , Pessoa de Meia-Idade , Países Baixos , Reprodutibilidade dos Testes , Semântica , Adulto Jovem
16.
Parasitol Res ; 113(6): 2311-22, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24728559

RESUMO

This study compared results obtained with five different fecal egg count reduction (FECR) calculation methods for defining resistance to ivermectin, fenbendazole, and levamisole in gastrointestinal nematodes of sheep in a temperate continental climate: FECR1 and FECR2 used pre- and posttreatment fecal egg count (FEC) means from both treated and control animals, but FECR1 used arithmetic means, whereas FECR2 used geometric means; FECR3 used arithmetic means for pre- and posttreatment FECs from treated animals only; FECR4 was calculated using only arithmetic means for posttreatment FECs from treated and control animals; and FECR5 was calculated using mean FEC estimates from a general linear mixed model. The classification of farm anthelmintic resistance (AR) status varied, depending on which FECR calculation method was used and whether a bias correction term (BCT, i.e., half the minimum detection limit) was added to the zeroes or not. Overall, agreement between all methods was higher when a BCT was used, particularly when levels of resistance were low. FECR4 showed the highest agreement with all the other FECR methods. We therefore recommend that small ruminant clinicians use the FECR4 formula with a BCT for AR determination, as this would reduce the cost of the FECRT, while still minimizing bias and allowing for comparisons between different farms. For researchers, we recommend the use of FECR1 or FECR2, as the inclusion of both pre- and posttreatment FECs and use of randomly allocated animals in treatment and control groups makes these methods mathematically more likely to estimate the true anthelmintic efficacy.


Assuntos
Anti-Helmínticos/farmacologia , Resistência a Medicamentos , Nematoides/efeitos dos fármacos , Infecções por Nematoides/veterinária , Doenças dos Ovinos/parasitologia , Animais , Clima , Fezes/parasitologia , Modelos Biológicos , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/parasitologia , Contagem de Ovos de Parasitas/veterinária , Ovinos , Doenças dos Ovinos/tratamento farmacológico
17.
J Cell Physiol ; 228(11): 2167-74, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23589129

RESUMO

In healthy bones, mineralization has to be tightly controlled to avoid pathological phenotypes. In this study, we investigated interactions between 1α,25(OH)2 D3 (1,25D3) and activin A in the regulation of osteoblast induced mineralization. In human osteoblast cultures, we demonstrated that besides stimulation of mineralization, 1,25D3 also induced activin A, a strong inhibitor of mineralization. Simultaneously, follistatin (FST), the natural antagonist of activin A, was down-regulated by1,25D3. This resulted in an increase in activin A activity during 1,25D3 treatment. We also showed that in 1,25D3-treated osteoblasts, mineralization can be further increased when activin A activity was abrogated by adding exogenous FST. This observation implies that, besides stimulation of mineralization, 1,25D3 also controls activin A-mediated inhibition of mineralization. Besides activin A, 1,25D3 also induces osteocalcin (BGLAP), another inhibitor of mineralization. Warfarin, which has been shown to inactivate osteocalcin, increased 1,25D3-induced mineralization. Interaction between these two systems became evident from the synergistic increase in BGLAP expression upon blocking activin activity in 1,25D3-treated cultures. In conclusion, we demonstrate that 1,25D3 stimulation of mineralization by human osteoblasts is suppressed by concomitant induction of inhibitors of mineralization. Mineralization induction by 1,25D3 may actually be controlled via interplay with activin A and osteocalcin. Finally, this complex regulation of mineralization substantiates the significance of tight control of mineralization to prevent excessive mineralization and consequently reduction in bone quality and strength.


Assuntos
Ativinas/biossíntese , Calcificação Fisiológica/efeitos dos fármacos , Osteoblastos/metabolismo , Vitamina D/análogos & derivados , Linhagem Celular , Folistatina/biossíntese , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Lectinas Tipo C/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteocalcina/genética , Osteocalcina/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Smad7/metabolismo , Vitamina D/farmacologia , Varfarina/farmacologia
18.
Nature ; 446(7139): 1082-5, 2007 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-17460673

RESUMO

Gliding birds continually change the shape and size of their wings, presumably to exploit the profound effect of wing morphology on aerodynamic performance. That birds should adjust wing sweep to suit glide speed has been predicted qualitatively by analytical glide models, which extrapolated the wing's performance envelope from aerodynamic theory. Here we describe the aerodynamic and structural performance of actual swift wings, as measured in a wind tunnel, and on this basis build a semi-empirical glide model. By measuring inside and outside swifts' behavioural envelope, we show that choosing the most suitable sweep can halve sink speed or triple turning rate. Extended wings are superior for slow glides and turns; swept wings are superior for fast glides and turns. This superiority is due to better aerodynamic performance-with the exception of fast turns. Swept wings are less effective at generating lift while turning at high speeds, but can bear the extreme loads. Finally, our glide model predicts that cost-effective gliding occurs at speeds of 8-10 m s(-1), whereas agility-related figures of merit peak at 15-25 m s(-1). In fact, swifts spend the night ('roost') in flight at 8-10 m s(-1) (ref. 11), thus our model can explain this choice for a resting behaviour. Morphing not only adjusts birds' wing performance to the task at hand, but could also control the flight of future aircraft.


Assuntos
Voo Animal/fisiologia , Aves Canoras/fisiologia , Asas de Animais/anatomia & histologia , Asas de Animais/fisiologia , Animais , Fenômenos Biomecânicos , Modelos Biológicos , Países Baixos , Aves Canoras/anatomia & histologia
19.
BMC Psychol ; 11(1): 245, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37626397

RESUMO

BACKGROUND: Stress-related disorders such as anxiety and depression are highly prevalent and cause a tremendous burden for affected individuals and society. In order to improve prevention strategies, knowledge regarding resilience mechanisms and ways to boost them is highly needed. In the Dynamic Modelling of Resilience - interventional multicenter study (DynaM-INT), we will conduct a large-scale feasibility and preliminary efficacy test for two mobile- and wearable-based just-in-time adaptive interventions (JITAIs), designed to target putative resilience mechanisms. Deep participant phenotyping at baseline serves to identify individual predictors for intervention success in terms of target engagement and stress resilience. METHODS: DynaM-INT aims to recruit N = 250 healthy but vulnerable young adults in the transition phase between adolescence and adulthood (18-27 years) across five research sites (Berlin, Mainz, Nijmegen, Tel Aviv, and Warsaw). Participants are included if they report at least three negative burdensome past life events and show increased levels of internalizing symptoms while not being affected by any major mental disorder. Participants are characterized in a multimodal baseline phase, which includes neuropsychological tests, neuroimaging, bio-samples, sociodemographic and psychological questionnaires, a video-recorded interview, as well as ecological momentary assessments (EMA) and ecological physiological assessments (EPA). Subsequently, participants are randomly assigned to one of two ecological momentary interventions (EMIs), targeting either positive cognitive reappraisal or reward sensitivity. During the following intervention phase, participants' stress responses are tracked using EMA and EPA, and JITAIs are triggered if an individually calibrated stress threshold is crossed. In a three-month-long follow-up phase, parts of the baseline characterization phase are repeated. Throughout the entire study, stressor exposure and mental health are regularly monitored to calculate stressor reactivity as a proxy for outcome resilience. The online monitoring questionnaires and the repetition of the baseline questionnaires also serve to assess target engagement. DISCUSSION: The DynaM-INT study intends to advance the field of resilience research by feasibility-testing two new mechanistically targeted JITAIs that aim at increasing individual stress resilience and identifying predictors for successful intervention response. Determining these predictors is an important step toward future randomized controlled trials to establish the efficacy of these interventions.


Assuntos
Resiliência Psicológica , Adolescente , Humanos , Adulto Jovem , Ansiedade , Transtornos de Ansiedade , Nível de Saúde , Saúde Mental , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
J Cell Physiol ; 227(9): 3258-66, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22105341

RESUMO

It is well established that 1α-25-dihydroxyvitamin D3 (1,25D3) regulates osteoblast function and stimulates mineralization by human osteoblasts. The aim of this study was to identify processes underlying the 1,25D3 effects on mineralization. We started with gene expression profiling analyses of differentiating human pre-osteoblast treated with 1,25D3. Bioinformatic analyses showed interferon-related and -regulated genes (ISG) to be overrepresented in the set of 1,25D3-regulated genes. 1,25D3 down-regulated ISGs predominantly during the pre-mineralization period. This pointed to an interaction between the vitamin D and IFN signaling cascades in the regulation of osteoblast function. Separately, 1,25D3 enhances while IFNß inhibits mineralization. Treatment of human osteoblasts with 1,25D3 and IFNß showed that 1,25D3 completely overrules the IFNß inhibition of mineralization. This was supported by analyses of extracellular matrix gene expression, showing a dominant effect of 1,25D3 over the inhibitory effect of IFNß. We identified processes shared by IFNß- and 1,25D3-mediated signaling by performing gene expression profiling during early osteoblast differentiation. Bioinformatic analyses revealed that genes being correlated or anti-correlated with interferon-induced protein with tetratricopeptide repeats 1 (IFIT1) were associated with osteoblast proliferation. In conclusion, the current study demonstrates a cross talk between 1,25D3 and IFNß in osteoblast differentiation and bone formation/mineralization. The interaction is complex and depends on the process but importantly, 1,25D3 stimulation of mineralization is dominant over the inhibitory effect of IFNß. These observations are of potential clinical relevance considering the impact of the immune system on bone metabolism in conditions such as rheumatoid arthritis.


Assuntos
Matriz Extracelular/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Interferon beta/genética , Osteoblastos/metabolismo , Vitamina D/metabolismo , Calcificação Fisiológica/efeitos dos fármacos , Calcificação Fisiológica/genética , Cálcio/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Matriz Extracelular/metabolismo , Genes Dominantes , Humanos , Interferon beta/metabolismo , Interferon beta/farmacologia , Transdução de Sinais , Vitamina D/análogos & derivados , Vitamina D/genética , Vitamina D/farmacologia
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