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1.
Nature ; 619(7970): 487-490, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37468588

RESUMO

Several long-period radio transients have recently been discovered, with strongly polarized coherent radio pulses appearing on timescales between tens to thousands of seconds1,2. In some cases, the radio pulses have been interpreted as coming from rotating neutron stars with extremely strong magnetic fields, known as magnetars; the origin of other, occasionally periodic and less-well-sampled radio transients is still debated3. Coherent periodic radio emission is usually explained by rotating dipolar magnetic fields and pair-production mechanisms, but such models do not easily predict radio emission from such slowly rotating neutron stars and maintain it for extended times. On the other hand, highly magnetic isolated white dwarfs would be expected to have long spin periodicities, but periodic coherent radio emission has not yet been directly detected from these sources. Here we report observations of a long-period (21 min) radio transient, which we have labelled GPM J1839-10. The pulses vary in brightness by two orders of magnitude, last between 30 and 300 s and have quasiperiodic substructure. The observations prompted a search of radio archives and we found that the source has been repeating since at least 1988. The archival data enabled constraint of the period derivative to <3.6 × 10-13 s s-1, which is at the very limit of any classical theoretical model that predicts dipolar radio emission from an isolated neutron star.

2.
Nature ; 601(7894): 526-530, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35082416

RESUMO

The high-frequency radio sky is bursting with synchrotron transients from massive stellar explosions and accretion events, but the low-frequency radio sky has, so far, been quiet beyond the Galactic pulsar population and the long-term scintillation of active galactic nuclei. The low-frequency band, however, is sensitive to exotic coherent and polarized radio-emission processes, such as electron-cyclotron maser emission from flaring M dwarfs1, stellar magnetospheric plasma interactions with exoplanets2 and a population of steep-spectrum pulsars3, making Galactic-plane searches a prospect for blind-transient discovery. Here we report an analysis of archival low-frequency radio data that reveals a periodic, low-frequency radio transient. We find that the source pulses every 18.18 min, an unusual periodicity that has, to our knowledge, not been observed previously. The emission is highly linearly polarized, bright, persists for 30-60 s on each occurrence and is visible across a broad frequency range. At times, the pulses comprise short-duration (<0.5 s) bursts; at others, a smoother profile is observed. These profiles evolve on timescales of hours. By measuring the dispersion of the radio pulses with respect to frequency, we have localized the source to within our own Galaxy and suggest that it could be an ultra-long-period magnetar.

3.
J Infect Dis ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38912968

RESUMO

BACKGROUND: The mechanisms that mediate immune protection in individuals with subclinical (SC) or asymptomatic infection with L. braziliensis are largely unknown. Neutrophils (PMNs) have been implicated in progressive symptomatic cutaneous leishmaniasis (CL), but their potential participation in maintenance of subclinical infection is unexplored. The aim of this study was to compare the phenotypic and functional profiles of PMNs in individuals with SC infection versus patients with symptomatic CL due to L. braziliensis. METHODS: Subjects were recruited in the endemic region of Corte de Pedra, Bahia, Brazil. Surface markers to define activation status were characterized by flow cytometry. Functional responses of PMNs including phagocytic capacity, production of oxidative species, and oxidative killing of intracellular parasites were studied in vitro. RESULTS: PMNs from individuals with SC infection displayed a more activated phenotype and greater ability to control the infection than PMNs from patients with CL. In contrast, PMNs from patients with CL exhibited higher expression of HLA-DR and higher production of oxidative species than PMNs from subjects with SC infection. CONCLUSION: PMNs from individuals with SC infection can control the infection more efficiently than PMNs from patients with CL, despite the lower production of oxidants. Our observations suggest that L. braziliensis may evade microbicidal mechanisms of PMNs from patients with CL, contributing to parasite dissemination and the establishment of disease.

4.
J Theor Biol ; 581: 111737, 2024 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-38280544

RESUMO

Xylem-limited bacterial pathogens cause some of the most destructive plant diseases. Though imposed measures to control these pathogens are generally ineffective, even among susceptible taxa, some hosts can limit bacterial loads and symptom expression. Mechanisms by which this resistance is achieved are poorly understood. In particular, it is still unknown how differences in vascular structure may influence biofilm growth and spread within a host. To address this, we developed a novel theoretical framework to describe biofilm behaviour within xylem vessels, adopting a polymer-based modelling approach. We then parameterised the model to investigate the relevance of xylem vessel diameters on Xylella fastidiosa resistance among olive cultivars. The functionality of all vessels was severely reduced under infection, with hydraulic flow reductions of 2-3 orders of magnitude. However, results suggest wider vessels act as biofilm incubators; allowing biofilms to develop over a long time while still transporting them through the vasculature. By contrast, thinner vessels become blocked much earlier, limiting biofilm spread. Using experimental data on vessel diameter distributions, we were able to determine that a mechanism of resistance in the olive cultivar Leccino is a relatively low abundance of the widest vessels, limiting X. fastidiosa spread.


Assuntos
Olea , Xylella , Olea/metabolismo , Olea/microbiologia , Biofilmes , Xilema , Doenças das Plantas/microbiologia , Modelos Teóricos
5.
Regul Toxicol Pharmacol ; 147: 105571, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38244664

RESUMO

The World Health Organization (WHO) assesses potential health risks of dioxin-like compounds using Toxic Equivalency Factors (TEFs). This study systematically updated the relative potency (REP) database underlying the 2005 WHO TEFs and applied advanced methods for quantitative integration of study quality and dose-response. Data obtained from fifty-one publications more than doubled the size of the previous REP database (∼1300 datasets). REP quality and relevance for these data was assessed via application of a consensus-based weighting framework. Using Bayesian dose-response modeling, available data were modeled to produce standardized dose/concentration-response Hill curves. Study quality and REP data were synthesized via Bayesian meta-analysis to integrate dose/concentration-response data, author-calculated REPs and benchmark ratios. The output is a prediction of the most likely relationship between each congener and its reference as model-predicted TEF uncertainty distributions, or the 'best estimate TEF' (BE-TEF). The resulting weighted BE-TEFs were similar to the 2005 TEFs, though provide more information to inform selection of TEF values as well as to provide risk assessors and managers with information needed to quantitatively characterize uncertainty around TEF values. Collectively, these efforts produce an updated REP database and an objective, reproducible approach to support development of TEF values based on all available data.


Assuntos
Dioxinas , Bifenilos Policlorados , Animais , Dioxinas/toxicidade , Teorema de Bayes , Mamíferos
6.
J Dairy Sci ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38851571

RESUMO

Although 3-NOP has been proven to reduce enteric methane (CH4) by ∼30% in indoor systems of dairying when the additive is mixed throughout a total mixed ration (TMR), there has been very limited research to date in grazing systems in which the most convenient method of additive supplementation is at milking twice daily. To investigate the effect of twice daily 3-NOP supplementation on enteric CH4 emissions, a 12-week study was undertaken in which treatment cows (n = 26) were supplemented with 3-NOP (80 mg per kg dry matter intake; DMI) twice daily at morning and evening milking, while control cows (n = 26) received no additive supplementation. Enteric CH4, hydrogen (H2) and carbon dioxide (CO2) were measured using GreenFeed units, while milk production, body weight (BW), body condition score (BCS) and DMI were monitored to determine the effect of 3-NOP supplementation on productivity. There was no significant effect of 3-NOP supplementation on any of the aforementioned parameters with the exception of CH4 and H2 production, respectively. Cows supplemented with 3-NOP produced ∼36% more H2 (P < 0.001) across a 24-h period, with reductions in CH4 production of 28.5% recorded in the 3 h after additive consumption (P < 0.001), however, levels of CH4 production returned to that of the control group thereafter. When CH4 production was considered across the entire 24-h period, the cows offered 3-NOP produced ∼5% less CH4 than the control (P < 0.050). Future research should focus on methods to increase the efficacy of the additive throughout the day which would include the deployment of a slow-release form or an out of parlor feeding system that allows animals consume the product at additional time points.

7.
Anal Bioanal Chem ; 415(27): 6757-6769, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37740752

RESUMO

Over the last decade, applications of ion mobility-mass spectrometry (IM-MS) have exploded due primarily to the widespread commercialization of robust instrumentation from several vendors. Unfortunately, the modest resolving power of many of these platforms (~40-60) has precluded routine separation of constitutional and stereochemical isomers. While instrumentation advances have pushed resolving power to >150 in some cases, chemical approaches offer an alternative for increasing resolution with existing IM-MS instrumentation. Herein we explore the utility of two reactions, derivatization by Girard's reagents and 1,1-carbonyldiimidazole (CDI), for improving IM separation of steroid hormone isomers. These reactions are fast (≤30 min), simple (requiring only basic lab equipment/expertise), and low-cost. Notably, these reactions are structurally selective in that they target carbonyl and hydroxyl groups, respectively, which are found in all naturally occurring steroids. Many steroid hormone isomers differ only in the number, location, and/or stereochemistry of these functional groups, allowing these reactions to "amplify" subtle structural differences and improve IM resolution. Our results show that resolution was significantly improved amongst CDI-derivatized isomer groups of hydroxyprogesterone (two-peak resolution of Rpp = 1.10 between 21-OHP and 11B-OHP), deoxycortisone (Rpp = 1.47 between 11-DHC and 21-DOC), and desoximetasone (Rpp = 1.98 between desoximetasone and fluocortolone). Moreover, characteristic collision cross section (DTCCSN2) measurements can be used to increase confidence in the identification of these compounds in complex biological mixtures. To demonstrate the feasibility of analyzing the derivatized steroids in complex biological matrixes, the reactions were performed following steroid extraction from urine and yielded similar results. Additionally, we applied a software-based approach (high-resolution demultiplexing) that further improved the resolving power (>150). Overall, our results suggest that targeted derivatization reactions coupled with IM-MS can significantly improve the resolution of challenging isomer groups, allowing for more accurate and efficient analysis of complex mixtures.

8.
J Infect Dis ; 226(5): 928-932, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-35510939

RESUMO

Current methods for tuberculosis treatment monitoring are suboptimal. We evaluated plasma matrix metalloproteinase (MMP) and procollagen III N-terminal propeptide concentrations before and during tuberculosis treatment as biomarkers. Plasma MMP-1, MMP-8, and MMP-10 concentrations significantly decreased during treatment. Plasma MMP-8 was increased in sputum Mycobacterium tuberculosis culture-positive relative to culture-negative participants, before (median, 4993 pg/mL [interquartile range, 2542-9188] vs 698 [218-4060] pg/mL, respectively; P = .004) and after (3650 [1214-3888] vs 720 [551-1321] pg/mL; P = .008) 6 months of tuberculosis treatment. Consequently, plasma MMP-8 is a potential biomarker to enhance tuberculosis treatment monitoring and screen for possible culture positivity.


Assuntos
Metaloproteinase 8 da Matriz , Tuberculose Pulmonar , Biomarcadores , Humanos , Metaloproteinase 8 da Matriz/sangue , Mycobacterium tuberculosis , Escarro , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/diagnóstico
9.
J Dairy Sci ; 104(8): 8721-8735, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34024597

RESUMO

The purpose of this study was to investigate the effect of 3-nitrooxypropanol (3-NOP), a potent methane inhibitor, on total and metabolically active methanogens in the rumen of dairy cows over the course of the day and over a 12-wk period. Rumen contents of 8 ruminally cannulated early-lactation dairy cows were sampled at 2, 6, and 10 h after feeding during wk 4, 8, and 12 of a randomized complete block design experiment in which 3-NOP was fed at 60 mg/kg of feed dry matter. Cows (4 fed the control and 4 fed the 3-NOP diet) were blocked based on their previous lactation milk yield or predicted milk yield. Rumen samples were extracted for microbial DNA (total) and microbial RNA (metabolically active), PCR amplified for the 16S rRNA gene of archaea, sequenced on an Illumina platform, and analyzed for archaea diversity. In addition, the 16S copy number and 3 ruminal methanogenic species were quantified using the real-time quantitative PCR assay. We detected a difference between DNA and RNA (cDNA)-based archaea communities, revealing that ruminal methanogens differ in their metabolic activities. Within DNA and cDNA components, methanogenic communities differed by sampling hour, week, and treatment. Overall, Methanobrevibacter was the dominant genus (94.3%) followed by Methanosphaera, with the latter genus having greater abundance in the cDNA component (14.5%) compared with total populations (5.5%). Methanosphaera was higher at 2 h after feeding, whereas Methanobrevibacter increased at 6 and 10 h in both groups, showing diurnal patterns among individual methanogenic lineages. Methanobrevibacter was reduced at wk 4, whereas Methanosphaera was reduced at wk 8 and 12 in cows supplemented with 3-NOP compared with control cows, suggesting differential responses among methanogens to 3-NOP. A reduction in Methanobrevibacter ruminantium in all 3-NOP samples from wk 8 was confirmed using real-time quantitative PCR. The relative abundance of individual methanogens was driven by a combination of dietary composition, dry matter intake, and hydrogen concentrations in the rumen. This study provides novel information on the effects of 3-NOP on individual methanogenic lineages, but further studies are needed to understand temporal dynamics and to validate the effects of 3-NOP on individual lineages of ruminal methanogens.


Assuntos
Propanóis , Rúmen , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Feminino , Fermentação , Lactação , Metano/metabolismo , Leite , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Rúmen/metabolismo
10.
J Dairy Sci ; 104(1): 357-366, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33131815

RESUMO

This study examined the effect of 3-nitrooxypropanol (3-NOP), an investigational substance, on enteric methane emission, milk production, and composition in Holstein dairy cows. Following a 3-wk covariate period, 48 multi- and primiparous cows averaging (± standard deviation) 118 ± 28 d in milk, 43.4 ± 8 kg/d milk yield, and 594 ± 57 kg of body weight were blocked based on days in milk, milk yield, and enteric methane emission and randomly assigned to 1 of 2 treatment groups: (1) control, no 3-NOP, and (2) 3-NOP applied at 60 mg/kg feed dry matter. Inclusion of 3-NOP was through the total mixed ration and fed for 15 consecutive weeks. Cows were housed in a freestall barn equipped with a Calan Broadbent Feeding System (American Calan Inc., Northwood, NH) for monitoring individual dry matter intake and fed ad libitum once daily. Enteric gaseous emissions (methane, carbon dioxide, and hydrogen) were measured using 3 GreenFeed (C-Lock Inc., Rapid City, SD) units. Dry matter intake, cow body weight, and body weight change were not affected by 3-NOP. Compared with the control group, 3-NOP applied at 60 mg/kg feed dry matter decreased daily methane emission, emission yield, and emission intensity by 26, 27, and 29%, respectively. Enteric emission of carbon dioxide was not affected, and hydrogen emission was increased 6-fold by 3-NOP. Administration of 3-NOP had no effect on milk and energy-corrected milk yields and feed efficiency, increased milk fat and milk urea nitrogen concentrations, and increased milk fat yield but had no other effects on milk components. Concentration of C6:0 and C8:0 and the sum of saturated fatty acids in milk fat were increased by 3-NOP. Total trans fatty acids and the sum of polyunsaturated fatty acids were decreased by 3-NOP. In this experiment, 3-NOP decreased enteric methane daily emission, yield, and intensity without affecting dry matter intake and milk yield, but increased milk fat in high-producing dairy cows.


Assuntos
Bovinos/metabolismo , Trato Gastrointestinal/efeitos dos fármacos , Lactação/efeitos dos fármacos , Metano/metabolismo , Leite/química , Propanóis/administração & dosagem , Animais , Dieta/veterinária , Ácidos Graxos/análise , Feminino , Trato Gastrointestinal/metabolismo , Lipídeos/análise , Leite/efeitos dos fármacos , Nitrogênio/análise
11.
Clin Exp Immunol ; 196(3): 287-304, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30985006

RESUMO

Plague caused by the Gram-negative bacterium, Yersinia pestis, is still endemic in parts of the world today. Protection against pneumonic plague is essential to prevent the development and spread of epidemics. Despite this, there are currently no licensed plague vaccines in the western world. Here we describe the means of delivering biologically active plague vaccine antigens directly to mucosal sites of plague infection using highly stable microvesicles (outer membrane vesicles; OMVs) that are naturally produced by the abundant and harmless human commensal gut bacterium Bacteroides thetaiotaomicron (Bt). Bt was engineered to express major plague protective antigens in its OMVs, specifically Fraction 1 (F1) in the outer membrane and LcrV (V antigen) in the lumen, for targeted delivery to the gastrointestinal (GI) and respiratory tracts in a non-human primate (NHP) host. Our key findings were that Bt OMVs stably expresses F1 and V plague antigens, particularly the V antigen, in the correct, immunogenic form. When delivered intranasally V-OMVs elicited substantive and specific immune and antibody responses, both in the serum [immunoglobulin (Ig)G] and in the upper and lower respiratory tract (IgA); this included the generation of serum antibodies able to kill plague bacteria. Our results also showed that Bt OMV-based vaccines had many desirable characteristics, including: biosafety and an absence of any adverse effects, pathology or gross alteration of resident microbial communities (microbiotas); high stability and thermo-tolerance; needle-free delivery; intrinsic adjuvanticity; the ability to stimulate both humoral and cell-mediated immune responses; and targeting of primary sites of plague infection.


Assuntos
Antígenos de Bactérias/metabolismo , Membrana Externa Bacteriana/metabolismo , Bacteroides thetaiotaomicron/metabolismo , Vacina contra a Peste/imunologia , Peste/imunologia , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Vesículas Transportadoras/imunologia , Yersinia pestis/fisiologia , Administração Intranasal , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/genética , Bacteroides thetaiotaomicron/genética , Bioengenharia , Morte Celular , Células Cultivadas , Microbioma Gastrointestinal/genética , Humanos , Imunidade Celular , Imunidade Humoral , Imunoglobulina A/metabolismo , Imunoglobulina G/sangue , Macaca , Peste/prevenção & controle , Vacina contra a Peste/metabolismo , Proteínas Citotóxicas Formadoras de Poros/genética , Vesículas Transportadoras/metabolismo
12.
BJOG ; 126(8): 1025-1031, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30811810

RESUMO

OBJECTIVE: Pregnancies in women with Loeys-Dietz syndrome (LDS) are rare and are typically documented in case reports only. Early reports suggested high rates of maternal complications during pregnancy and the puerperium, including aortic dissection and uterine rupture, but information on fetal outcomes was very limited. DESIGN: A retrospective cohort study. SETTING: Eight specialist UK centres. SAMPLE: Pregnant women with LDS. METHODS: Data was collated on cardiac, obstetric, and neonatal outcomes. MAIN OUTCOME MEASURES: Maternal and perinatal outcomes in pregnancies complicated by LDS. RESULTS: Twenty pregnancies in 13 women with LDS were identified. There was one miscarriage, one termination of pregnancy, and 18 livebirths. In eight women the diagnosis was known prior to pregnancy but only one woman had preconception counselling. In four women the diagnosis was made during pregnancy through positive genotyping, and the other was diagnosed following delivery. Five women had a family history of aortic dissection. There were no aortic dissections in our cohort during pregnancy or postpartum. Obstetric complications were common, including postpartum haemorrhage (33%) and preterm delivery (50%). In all, 14/18 (78%) of deliveries were by elective caesarean section, at a median gestational age at delivery of 37 weeks. Over half the infants (56%) were admitted to the neonatal unit following delivery. CONCLUSION: Women with LDS require multidisciplinary specialist management throughout pregnancy. Women should be referred for preconception counselling to make informed decisions around pregnancy risk and outcomes. Early elective preterm delivery needs to be balanced against a high infant admission rate to the neonatal unit. TWEETABLE ABSTRACT: Pregnancy outcomes in women with Loeys-Dietz syndrome.


Assuntos
Síndrome de Loeys-Dietz/complicações , Complicações na Gravidez/etiologia , Resultado da Gravidez , Adulto , Parto Obstétrico/métodos , Feminino , Humanos , Recém-Nascido , Hemorragia Pós-Parto/etiologia , Gravidez , Nascimento Prematuro/etiologia , Estudos Retrospectivos , Fatores de Risco , Reino Unido/epidemiologia
13.
Xenobiotica ; 49(9): 1078-1085, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30257131

RESUMO

Fullerene C60 is used in a variety of industrial and consumer capacities. As part of a comprehensive evaluation of the toxicity of fullerene C60 by the National Toxicology Program, the disposition following intratracheal (IT) instillation and intravenous (IV) administration of 1 or 5 mg/kg b.wt. fullerene C60 was investigated in male Fischer 344 rats. Following IT instillation, fullerene C60 was detected in the lung as early as 0.5 h post-exposure with minimal clearance over the 168 h period; the concentration increased ≥20-fold with a 5-fold increase in the dose. Fullerene C60 was not detected in extrapulmonary tissues. Following IV administration, fullerene C60 was rapidly eliminated from the blood and was undetectable after 0.5 h post-administration. The highest tissue concentrations of fullerene C60 occurred in the liver, followed by the spleen, lung and kidney. Fullerene C60 was cleared slowly from the kidney and the lung with estimated half-lives of 24 and 139 h, respectively. The liver concentration of fullerene C60 did not change much with time; over 90% of the fullerene C60 remained there over the study duration up to 168 h. Fullerene C60 was also not detected in urine or feces. These data support the hypothesis that fullerene C60 accumulates in the body and therefore has the potential to induce detrimental health effects following exposure.


Assuntos
Fulerenos/administração & dosagem , Fulerenos/farmacocinética , Administração por Inalação , Administração Intravenosa , Animais , Cromatografia Líquida , Fulerenos/química , Masculino , Espectrometria de Massas , Microscopia Eletrônica de Varredura , Ratos Endogâmicos F344 , Distribuição Tecidual
14.
Scand J Med Sci Sports ; 28(1): 303-310, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28455943

RESUMO

Ultrasound tissue characterization (UTC) is an imaging tool used to quantify tendon structural integrity. UTC has quantified Achilles tendon (AT) acute response to load in athletes; however, AT response to cumulative load over a season is unknown. The purpose of this study was to evaluate AT response across a four-month competitive season in collegiate cross-country (XC) runners. Participants (n=21; male=9, female=12; age=19.8±1.2 years; height=171.9±8.9 cm; weight=60.2±8.5 kg) were imaged using the UTC device with a 10-MHz linear-array transducer mounted in a tracking device. The device captures images at 0.2 mm intervals along the AT. UTC algorithms quantified the stability of pixel brightness over every 17 contiguous transverse images into four echo types (I-IV). A total of 168 scans (n=21, bilateral limbs) were performed monthly across the four-month season (Aug=M1, Sep=M2, Oct=M3, Nov=M4). Echo-type percentages (%) were calculated from each scan. Generalized estimating equations (GEE) linear regression models evaluated echo-type % change (ß) over the season (M1=reference). Type I increased from M1 to M4 (ß=9.10, P<.01; 95%CI: 7.01, 11.21) and Type II decreased from M1 to M3 (ß=-2.71, P=.018; 95%CI: -4.96, -0.47) and M1 to M4 (ß=-10.19, P<.01; 95%CI: -12.22, -8.17). Type III increased from M1 to M3 (ß=0.42, P=.003; 95%CI: 0.19, 0.65) and M1 to M4 (ß=0.49, P=.002; 95%CI: 0.18, 0.81), Type IV increased from M1 to M4 (ß=0.57, P<.01; 95%CI: 0.29, 0.84). A positive adaptation in AT structural integrity was observed over the XC season, with a ~10% shift from Type II to Type I UTC echo types, suggesting AT resilience to a competitive season of repetitive loading in highly trained runners.


Assuntos
Tendão do Calcâneo/diagnóstico por imagem , Tendão do Calcâneo/fisiologia , Adaptação Fisiológica , Corrida/fisiologia , Adolescente , Feminino , Humanos , Modelos Lineares , Masculino , Estudos Prospectivos , Fatores de Tempo , Ultrassonografia , Adulto Jovem
15.
J Oral Rehabil ; 45(1): 34-40, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28965355

RESUMO

As the understanding of temporomandibular disorders' (TMDs) aetiologies and treatments develops from non-evidence-based to evidence-based approaches, the availability of sound information will likewise grow and need to be disseminated. The purpose of this study is to describe the content most commonly viewed in YouTube videos related to TMDs or "TMJ" and see whether videos from different sources have different content. Video information was gathered by searching YouTube for the term "TMJ," and data were recorded related to descriptive information as well as content. Statistical analyses included Kruskal-Wallis H Test, Spearman's Rho and univariate logistic regression. The sources of upload were Consumer (n = 62), Professional (n = 29) and News (n = 9). There were almost no statistically significant differences in content distribution among video sources. Videos garnered a total of 4 749 360 views, with an overall median of 7014.5 views. About two-thirds of the videos (68/100) explained what "TMJ" is, with a surprising third of Professional videos (9/29) not covering the subject. Roughly half of the videos mentioned at least one reason "TMJ" occurs (55/100), and seven in ten mentioned some kind of treatment (70/100). Video names mentioned a cure or treatment in 64 cases, while the other 36 referred to TMJ anatomy or "TMJ" aetiology. Future research should focus on ways to popularise professional videos with reliable information for those who are searching on YouTube for advice related to "TMJ."


Assuntos
Internet , Transtornos da Articulação Temporomandibular , Articulação Temporomandibular , Medicina Baseada em Evidências , Humanos , Disseminação de Informação , Comportamento de Busca de Informação , Mídias Sociais , Gravação em Vídeo
16.
J Dairy Sci ; 100(7): 5449-5461, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28527799

RESUMO

The aims of the present study were to evaluate the effects of live yeast supplementation (Vistacell MUCL 39855, AB Vista, Marlborough, UK) on performance, rumination time, and rumen pH on dairy cows in commercial farm environments. Three trials were carried out, the trials lasted 12 (trial 1), 15 (trial 2), and 19 wk (trial 3). In each trial, 14 multiparous Holstein dairy cows were allocated to 2 groups that received (trial 1) a standard diet plus yeast, (trial 2) an acidogenic diet plus yeast, and (trial 3) grazing pasture plus yeast. Milk production, milk chemical characteristics, body weight and body condition score, rumination time, and rumen pH were monitored for each group throughout the 3 trials. No statistically significant differences were observed in any of the 3 trials for any of the recorded variables. In contrast, an effect of time (period or days in milk) on rumen pH was observed in all 3 of the trials, as time spent under the acidotic thresholds increased across the experimental periods; however the differences were not associated with live yeast supplementation. No effect of live yeast supplementation was observed in any of the 3 trials reported. Further research should include studies on animals at different stages of lactation (with emphasis on transition period and early lactation), consuming more challenging diets (higher level of inclusion of concentrates or starch), or under different environments such as grazing of succulent forages. Such studies might be required to elucidate any possible effect of live yeast supplementation of dairy cows when the rumen environment is under challenge.


Assuntos
Dieta/veterinária , Leite/metabolismo , Fermento Seco/administração & dosagem , Fenômenos Fisiológicos da Nutrição Animal , Animais , Peso Corporal , Bovinos , Comércio , Fazendas , Feminino , Concentração de Íons de Hidrogênio , Lactação , Leite/química , Rúmen/química , Rúmen/metabolismo , Fatores de Tempo
17.
Psychol Med ; 46(5): 1069-78, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26671170

RESUMO

BACKGROUND: The attenuated positive symptoms syndrome (APSS) is considered an at-risk indicator for psychosis. However, the characteristics and developmental aspects of the combined or enriched risk criteria of APSS and basic symptom (BS) criteria, including self-experienced cognitive disturbances (COGDIS) remain under-researched. METHOD: Based on the Structured Interview of Prodromal Syndromes (SIPS), the prevalence of APSS in 13- to 35-year-old individuals seeking help in an early recognition program for schizophrenia and bipolar-spectrum disorders was examined. BS criteria and COGDIS were rated using the Schizophrenia Proneness Instrument for Adults/Children and Youth. Participants meeting APSS criteria were compared with participants meeting only BS criteria across multiple characteristics. Co-occurrence (APSS+/BS+, APSS+/COGDIS+) was compared across 13-17, 18-22 and 23-35 years age groups. RESULTS: Of 175 individuals (age = 20.6 ± 5.8, female = 38.3%), 94 (53.7%) met APSS criteria. Compared to BS, APSS status was associated with suicidality, higher illness severity, lower functioning, higher SIPS positive, negative, disorganized and general symptoms scores, depression scores and younger age (18.3 ± 5.0 v. 23.2 ± 5.6 years, p < 0.0001) with age-related differences in the prevalence of APSS (ranging from 80.3% in 13- to 17-year-olds to 33.3% in 23- to 35-year-olds (odds ratio 0.21, 95% confidence interval 0.11-0.37). Within APSS+ individuals, fewer adolescents fulfilled combined risk criteria of APSS+/BS+ or APSS+/COGDIS+ compared to the older age groups. CONCLUSIONS: APSS status was associated with greater suicidality and illness/psychophathology severity in this help-seeking cohort, emphasizing the need for clinical care. The age-related differences in the prevalence of APSS and the increasing proportion of APSS+/COGDIS+ may point to a higher proportion of non-specific/transient, rather than risk-specific attenuated positive symptoms in adolescents.


Assuntos
Antipsicóticos/uso terapêutico , Sintomas Prodrômicos , Transtornos Psicóticos/tratamento farmacológico , Transtornos Psicóticos/epidemiologia , Suicídio/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Feminino , Humanos , Modelos Logísticos , Masculino , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/classificação , Fatores de Risco , Índice de Gravidade de Doença , Suíça/epidemiologia , Adulto Jovem
18.
BMC Public Health ; 16(1): 1038, 2016 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-27716223

RESUMO

BACKGROUND: Smoking cessation services are available in England to provide assistance to those wishing to quit smoking. Data from one such service were analysed in order to investigate differences in quit rate between males and females prescribed with different treatments. METHODS: A logistic regression model was fitted to the data using the binary response of self-reported quit (failed attempt = 0, successful attempt = 1), validated by Carbon Monoxide (CO) monitoring, 4 weeks after commencing programme. Main effects fitted were: client gender; age; region; the type of advisory sessions; and pharmacotherapy, Nicotine Replacement Therapy (NRT) or Varenicline. A second model was fitted including all main effects plus two-way interactions except region. These models were repeated using 12-week self-reported quit as the outcome. RESULTS: At 4 weeks, all main effects were statistically significant, with males more likely (odds ratio and 95 % CI, females v males = 0.88 [0.79-0.97]), older smokers more likely (adjusted odds ratios [OR] and 95 % confidence interval [CI] respectively for groups 20-29, 30-49, 50-69 and 70+ vs 12-19 age group: 1.79 [1.39-2.31], 2.12 [1.68-2.68], 2.30 [1.80-2.92] and 2.47 [1.81-3.37] and for overall difference between groups, χ2(4) = 53.5, p < 0.001) and clients being treated with Varenicline more likely to have successfully quit than those on NRT (adjusted OR and 95 % CI for Varenicline vs NRT = 1.41 [1.21-1.64]). Statistically significant interactions were observed between (i) gender and type of counselling, and (ii) age and type of counselling. Similar results were seen in relation to main effects at 12 weeks except that type of counselling was non-significant. The only significant interaction at this stage was between gender and pharmacotherapy (adjusted OR and 95 % CI for females using Varenicline versus all other groups = 1.43 [1.06-1.94]). CONCLUSION: Gender and treatment options were identified as predictors of abstinence at both 4 and 12 weeks after quitting smoking. Furthermore, interactions were observed between gender and (i) type of counselling received (ii) pharmacotherapy. In particular, the quit rate in women at 12 weeks was significantly improved in conjunction with Varenicline use. These findings have implications for service delivery.


Assuntos
Agonistas Nicotínicos/uso terapêutico , Abandono do Hábito de Fumar/métodos , Fumar/tratamento farmacológico , Tabagismo/tratamento farmacológico , Adolescente , Adulto , Idoso , Benzazepinas/uso terapêutico , Aconselhamento/métodos , Inglaterra , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Quinoxalinas/uso terapêutico , Fatores Sexuais , Vareniclina/uso terapêutico , Adulto Jovem
19.
BMC Health Serv Res ; 16: 307, 2016 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-27460830

RESUMO

BACKGROUND: As part of an electronic dashboard operated by Public Health Wales, senior managers at hospitals in Wales report daily "escalation" scores which reflect management opinion on the pressure a hospital is experiencing and ability to meet ongoing demand with respect to unscheduled care. An analysis was undertaken of escalation scores returned for 18 hospitals in Wales between the years 2006 and 2014 inclusive, with a view to identifying systematic temporal patterns in pressure experienced by hospitals in relation to unscheduled care. METHODS: Exploratory data analysis indicated the presence of within-year cyclicity in average daily scores over all hospitals. In order to quantify this cyclicity, a Generalised Linear Mixed Model was fitted which incorporated a trigonometric function (sine and cosine) to capture within-year change in escalation. In addition, a 7-level categorical day of the week effect was fitted as well as a 3-level categorical Christmas holiday variable based on patterns observed in exploration of the raw data. RESULTS: All of the main effects investigated were found to be statistically significant. Firstly, significant differences emerged in terms of overall pressure reported by individual hospitals. Furthermore, escalation scores were found to vary systematically within-year in a wave-like fashion for all hospitals (but not between hospitals) with the period of highest pressure consistently observed to occur in winter and lowest pressure in summer. In addition to this annual variation, pressure reported by hospitals was also found to be influenced by day of the week (low at weekends, high early in the working week) and especially low over the Christmas period but high immediately afterwards. CONCLUSIONS: Whilst unpredictable to a degree, quantifiable pressure experienced by hospitals can be anticipated according to models incorporating systematic temporal patterns. In the context of finite resources for healthcare services, these findings could optimise staffing schedules and inform resource utilisation.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Estações do Ano , Adulto , Recursos em Saúde , Serviços de Saúde , Férias e Feriados/estatística & dados numéricos , Hospitais/estatística & dados numéricos , Humanos , Modelos Lineares , Fatores de Tempo , País de Gales
20.
Psychol Med ; 45(10): 2123-34, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25640248

RESUMO

BACKGROUND: Neurocognitive deficits are important aspects of schizophrenic disorder because they have a strong impact on social and vocational outcomes. Previously it was assumed that cognitive abilities progressively deteriorate with illness onset. However, recent research results have contradicted this with observations of continuous or even improved performance in individuals at risk for psychosis or manifest schizophrenia. The objective of our longitudinal study was to examine neurocognitive functioning in help-seeking individuals meeting basic symptoms or ultra-high-risk criteria for schizophrenic psychosis (HRSchiz) or risk criteria for affective psychosis (HRBip). The progression of cognitive functioning in individuals converting to psychosis was compared with that of at-risk individuals who did not convert during the follow-up period. METHOD: Data were available from 86 study participants who completed neurocognitive and clinical assessments at baseline and, on average, 12.8 (s.d. = 1.5) months later. Neurocognitive measures were grouped according to their load in factor analysis to five cognitive domains: speed, attention, fluency, learning and memory, and working memory. RESULTS: Neurocognitive functioning in HRSchiz and HRBip individuals generally improved over time. Subjects converting to manifest psychosis displayed a stable neurocognitive profile from baseline to follow-up. Compared with non-converters, they had already demonstrated a significantly lower level of performance during their baseline examinations. CONCLUSIONS: Our data provide no evidence for a progressive cognitive decline in individuals at risk of psychosis. In line with the neurodevelopmental model, our findings suggest that cognitive deficits are already present very early, before or during the prodromal stage of the illness.


Assuntos
Transtorno Bipolar/psicologia , Transtornos Neurocognitivos/psicologia , Adolescente , Adulto , Análise de Variância , Antipsicóticos/uso terapêutico , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/tratamento farmacológico , Cognição , Feminino , Humanos , Estudos Longitudinais , Masculino , Testes Neuropsicológicos , Sintomas Prodrômicos , Escalas de Graduação Psiquiátrica , Esquizofrenia/diagnóstico , Esquizofrenia/tratamento farmacológico , Psicologia do Esquizofrênico , Suíça , Adulto Jovem
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