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1.
BMC Microbiol ; 21(1): 243, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34488648

RESUMO

BACKGROUND: Understanding the specificity and flexibility of the algal symbiosis-host association is fundamental for predicting how species occupy a diverse range of habitats. Here we assessed the algal symbiosis diversity of three species of larger benthic foraminifera from the genus Amphistegina and investigated the role of habitat and species identity in shaping the associated algal community. RESULTS: We used next-generation sequencing to identify the associated algal community, and DNA barcoding to identify the diatom endosymbionts associated with species of A. lobifera, A. lessonii, and A. radiata, collected from shallow habitats (< 15 m) in 16 sites, ranging from the Mediterranean Sea to French Polynesia. Next-generation sequencing results showed the consistent presence of Ochrophyta as the main algal phylum associated with all species and sites analysed. A significant proportion of phylotypes were classified as Chlorophyta and Myzozoa. We uncovered unprecedented diversity of algal phylotypes found in low abundance, especially of the class Bacillariophyta (i.e., diatoms). We found a significant influence of sites rather than host identity in shaping algal communities in all species. DNA barcoding revealed the consistent presence of phylotypes classified within the order Fragilariales as the diatoms associated with A. lobifera and A. lessonii, while A. radiata specimens host predominately diatoms of the order Triceratiales. CONCLUSIONS: We show that local habitat is the main factor influencing the overall composition of the algal symbiont community. However, host identity and the phylogenetic relationship among hosts is relevant in shaping the specific endosymbiont diatom community, suggesting that the relationship between diatom endosymbiont and hosts plays a crucial role in the evolutionary history of the genus Amphistegina. The capacity of Amphistegina species to associate with a diverse array of diatoms, and possibly other algal groups, likely underpins the ecological success of these crucial calcifying organisms across their extensive geographic range.


Assuntos
Ecossistema , Foraminíferos/genética , Variação Genética , Simbiose , Recifes de Corais , Código de Barras de DNA Taxonômico , Diatomáceas/genética , Foraminíferos/classificação , Sequenciamento de Nucleotídeos em Larga Escala , Oceanos e Mares , Filogenia
2.
BJOG ; 128(9): 1534-1545, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33969614

RESUMO

OBJECTIVE: To assess the cost-effectiveness of mifepristone and misoprostol (MifeMiso) compared with misoprostol only for the medical management of a missed miscarriage. DESIGN: Within-trial economic evaluation and model-based analysis to set the findings in the context of the wider economic evidence for a range of comparators. Incremental costs and outcomes were calculated using nonparametric bootstrapping and reported using cost-effectiveness acceptability curves. Analyses were performed from the perspective of the UK's National Health Service (NHS). SETTING: Twenty-eight UK NHS early pregnancy units. SAMPLE: A cohort of 711 women aged 16-39 years with ultrasound evidence of a missed miscarriage. METHODS: Treatment with mifepristone and misoprostol or with matched placebo and misoprostol tablets. MAIN OUTCOME MEASURES: Cost per additional successfully managed miscarriage and quality-adjusted life years (QALYs). RESULTS: For the within-trial analysis, MifeMiso intervention resulted in an absolute effect difference of 6.6% (95% CI 0.7-12.5%) per successfully managed miscarriage and a QALYs difference of 0.04% (95% CI -0.01 to 0.1%). The average cost per successfully managed miscarriage was lower in the MifeMiso arm than in the placebo and misoprostol arm, with a cost saving of £182 (95% CI £26-£338). Hence, the MifeMiso intervention dominated the use of misoprostol alone. The model-based analysis showed that the MifeMiso intervention is preferable, compared with expectant management, and this is the current medical management strategy. However, the model-based evidence suggests that the intervention is a less effective but less costly strategy than surgical management. CONCLUSIONS: The within-trial analysis found that based on cost-effectiveness grounds, the MifeMiso intervention is likely to be recommended by decision makers for the medical management of women presenting with a missed miscarriage. TWEETABLE ABSTRACT: The combination of mifepristone and misoprostol is more effective and less costly than misoprostol alone for the management of missed miscarriages.


Assuntos
Abortivos/administração & dosagem , Aborto Retido/tratamento farmacológico , Mifepristona/administração & dosagem , Misoprostol/administração & dosagem , Abortivos/economia , Aborto Retido/economia , Adolescente , Adulto , Análise Custo-Benefício , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Mifepristona/economia , Misoprostol/economia , Gravidez , Adulto Jovem
3.
Mol Phylogenet Evol ; 153: 106944, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32860973

RESUMO

Targeted enrichment of genomic DNA can profoundly increase the phylogenetic resolution of clades and inform taxonomy. Here, we redesign a custom bait set previously developed for the cnidarian class Anthozoa to more efficiently target and capture ultraconserved elements (UCEs) and exonic loci within the subclass Hexacorallia. We test this enhanced bait set (targeting 2476 loci) on 99 specimens of scleractinian corals spanning both the "complex" (Acroporidae, Agariciidae) and "robust" (Fungiidae) clades. Focused sampling in the staghorn corals (genus Acropora) highlights the ability of sequence capture to inform the taxonomy of a clade previously deficient in molecular resolution. A mean of 1850 (±298) loci were captured per taxon (955 UCEs, 894 exons), and a 75% complete concatenated alignment of 96 samples included 1792 loci (991 UCE, 801 exons) and ~1.87 million base pairs. Maximum likelihood and Bayesian analyses recovered robust molecular relationships and revealed that species-level relationships within the Acropora are incongruent with traditional morphological groupings. Both UCE and exon datasets delineated six well-supported clades within Acropora. The enhanced bait set will facilitate investigations of the evolutionary history of many important groups of reef corals, particularly where previous molecular marker development has been unsuccessful.


Assuntos
Antozoários/classificação , Filogenia , Animais , Antozoários/genética , Teorema de Bayes
4.
Amino Acids ; 52(5): 711-724, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32318874

RESUMO

Erythrocytes have a well-defined role in the gaseous exchange of oxygen and carbon dioxide in the mammalian body. The erythrocytes can contain more than half of the free amino acids present in whole blood. Based on measures showing that venous erythrocyte levels of amino acids are much less than arterial erythrocyte levels, it has previously been proposed that erythrocytes also play a role in the delivery of amino acids to tissues in the body. This role has been dismissed because it has been assumed that to act as an amino acid transport vehicle, the erythrocytes should release their entire amino acid content in the capillary beds at the target tissues with kinetic studies showing that this would take too long to achieve. This investigation set out to investigate whether the equine erythrocytes could rapidly take up and release smaller packages of amino acids when exposed to high or low external concentrations of amino acids, because it seemed very unlikely that cells would be able to release all of their amino acids without serious impacts on osmotic balance. Freshly prepared erythrocytes were placed in alternating solutions of high and low amino acid concentrations in PBS to assess the capacities of these cells to rapidly take up and release amino acids depending on the nature of the external environment. It was found that amino acids were rapidly taken up and released in small quantities in each cycle representing 15% of their total load in equine erythrocytes and 16% in human erythrocytes. The capacity for rapid uptake/release of amino acids by equine and human erythrocytes provided evidence to support the theory that mammalian erythrocytes have a significant role in transport of amino acids from the liver to tissues, muscles and organs.


Assuntos
Aminoácidos/farmacocinética , Eritrócitos/metabolismo , Fígado/metabolismo , Músculos/metabolismo , Animais , Transporte Biológico , Cavalos , Humanos , Fígado/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Músculos/irrigação sanguínea , Distribuição Tecidual
5.
BJOG ; 127(6): 757-767, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32003141

RESUMO

OBJECTIVES: To assess the cost-effectiveness of progesterone compared with placebo in preventing pregnancy loss in women with early pregnancy vaginal bleeding. DESIGN: Economic evaluation alongside a large multi-centre randomised placebo-controlled trial. SETTING: Forty-eight UK NHS early pregnancy units. POPULATION: Four thousand one hundred and fifty-three women aged 16-39 years with bleeding in early pregnancy and ultrasound evidence of an intrauterine sac. METHODS: An incremental cost-effectiveness analysis was performed from National Health Service (NHS) and NHS and Personal Social Services perspectives. Subgroup analyses were carried out on women with one or more and three or more previous miscarriages. MAIN OUTCOME MEASURES: Cost per additional live birth at ≥34 weeks of gestation. RESULTS: Progesterone intervention led to an effect difference of 0.022 (95% CI -0.004 to 0.050) in the trial. The mean cost per woman in the progesterone group was £76 (95% CI -£559 to £711) more than the mean cost in the placebo group. The incremental cost-effectiveness ratio for progesterone compared with placebo was £3305 per additional live birth. For women with at least one previous miscarriage, progesterone was more effective than placebo with an effect difference of 0.055 (95% CI 0.014-0.096) and this was associated with a cost saving of £322 (95% CI -£1318 to £673). CONCLUSIONS: The results suggest that progesterone is associated with a small positive impact and a small additional cost. Both subgroup analyses were more favourable, especially for women who had one or more previous miscarriages. Given available evidence, progesterone is likely to be a cost-effective intervention, particularly for women with previous miscarriage(s). TWEETABLE ABSTRACT: Progesterone treatment is likely to be cost-effective in women with early pregnancy bleeding and a history of miscarriage.


Assuntos
Aborto Espontâneo/economia , Aborto Espontâneo/prevenção & controle , Progesterona/economia , Progestinas/economia , Hemorragia Uterina/tratamento farmacológico , Aborto Espontâneo/etiologia , Adolescente , Adulto , Análise Custo-Benefício , Método Duplo-Cego , Feminino , Humanos , Nascido Vivo/economia , Gravidez , Progesterona/uso terapêutico , Progestinas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Medicina Estatal , Resultado do Tratamento , Reino Unido , Hemorragia Uterina/complicações , Hemorragia Uterina/economia , Adulto Jovem
6.
Magn Reson Med ; 82(5): 1631-1645, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31183892

RESUMO

PURPOSE: To investigate the potential of continuous radiofrequency (RF) shifting (SWEEP) as a technique for creating densely sampled data while maintaining a stable signal state for dynamic imaging. METHODS: We present a method where a continuous stable state of magnetization is swept smoothly across the anatomy of interest, creating an efficient approach to dense multiple 2D slice imaging. This is achieved by introducing a linear frequency offset to successive RF pulses shifting the excited slice by a fraction of the slice thickness with each successive repeat times (TR). Simulations and in vivo imaging were performed to assess how this affects the measured signal. Free breathing, respiration resolved 4D volumes in fetal/placental imaging is explored as potential application of this method. RESULTS: The SWEEP method maintained a stable signal state over a full acquisition reducing artifacts from unstable magnetization. Simulations demonstrated that the effects of SWEEP on slice profiles was of the same order as that produced by physiological motion observed with conventional methods. Respiration resolved 4D data acquired with this method shows reduced respiration artifacts and resilience to non-rigid and non-cyclic motion. CONCLUSIONS: The SWEEP method is presented as a technique for improved acquisition efficiency of densely sampled short-TR 2D sequences. Using conventional slice excitation the number of RF pulses required to enter a true steady state is excessively high when using short-TR 2D acquisitions, SWEEP circumvents this limitation by creating a stable signal state that is preserved between slices.


Assuntos
Imageamento por Ressonância Magnética/métodos , Respiração , Artefatos , Mapeamento Encefálico/métodos , Simulação por Computador , Feminino , Humanos , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Angiografia por Ressonância Magnética , Placenta/irrigação sanguínea , Placenta/diagnóstico por imagem , Gravidez
7.
Amino Acids ; 51(6): 945-959, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31028564

RESUMO

The nitrogen balance is regulated by factors such as diet, physical activity, age, pathogenic challenges, and climatic conditions. A paradigm was developed from published recommended rates of protein intake (g/kg/day) with corresponding rates of endogenous protein turnover and excretion, to extrapolate amino acid balances under various conditions. The average proportions of amino acids in the ingested proteins representing a well-balanced diet were used to assess intake and an average human composition profile from five major high-turnover proteins in the body to assess endogenous protein turnover. The amino acid excretion profiles for urine and sweat were constructed for males and females from published data. The model calculated the nitrogen balances for a range of amino acids to determine the amino acid requirements to support daily exertion. Histidine, serine, glycine, and ornithine were in negative balances in males and females and this potential deficit was greater in the higher body-mass ranges. Conversely, leucine, isoleucine, and valine were conserved during nitrogen flux and resulted in positive balances. The model was run under a scenario of high demand for the synthesis of IgG during a response to an infectious challenge which indicated that these were increased requirements for tyrosine, threonine, and valine. It was concluded that these amino acids represent points of limitation to anabolic metabolism by restriction of their supply at critical times of demand. This would especially occur under conditions of fitness training, maintaining intensive exercise regimes, facilitating responses to pathogenic challenge, or recovery from injury.


Assuntos
Aminoácidos/metabolismo , Proteínas Alimentares/metabolismo , Ciclo do Nitrogênio/fisiologia , Aminoácidos/urina , Feminino , Humanos , Masculino , Modelos Biológicos , Nitrogênio/metabolismo
8.
Biol Lett ; 15(10): 20190493, 2019 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-31662067

RESUMO

Natural environmental gradients encompass systematic variation in abiotic factors that can be exploited to test competing explanations of biodiversity patterns. The species-energy (SE) hypothesis attempts to explain species richness gradients as a function of energy availability. However, limited empirical support for SE is often attributed to idiosyncratic, local-scale processes distorting the underlying SE relationship. Meanwhile, studies are also often confounded by factors such as sampling biases, dispersal boundaries and unclear definitions of energy availability. Here, we used spatially structured observations of 8460 colonies of photo-symbiotic reef-building corals and a null-model to test whether energy can explain observed coral species richness over depth. Species richness was left-skewed, hump-shaped and unrelated to energy availability. While local-scale processes were evident, their influence on species richness was insufficient to reconcile observations with model predictions. Therefore, energy availability, either in isolation or in combination with local deterministic processes, was unable to explain coral species richness across depth. Our results demonstrate that local-scale processes do not necessarily explain deviations in species richness from theoretical models, and that the use of idiosyncratic small-scale factors to explain large-scale ecological patterns requires the utmost caution.


Assuntos
Antozoários , Animais , Biodiversidade , Ecologia , Modelos Biológicos
9.
Br Poult Sci ; 60(3): 209-218, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27848267

RESUMO

1. The two red grain sorghums were extensively characterised. Kafirin, polyphenolic compounds, free, conjugated and bound phenolic acids, phytate concentrations and starch pasting profiles were determined. 2. The experiment consisted of a 2 × 4 factorial array of dietary treatments comprising two red sorghum varieties (Tiger and Block I) ground through 4 hammer-mill screen sizes (2.0, 3.2, 4.8 6.0 mm) prior to incorporation into nutritionally equivalent diets. Eight steam-pelleted dietary treatments were each offered to 7 replicates (6 male Ross 308 birds per cage) from 7 to 28 d post-hatch. 3. Effects of dietary treatments on growth performance, relative gizzard and pancreas weights, nutrient utilisation, apparent starch and protein (N) digestibility coefficients and disappearance rates from 4 small intestinal segments were determined. 4. The 2.0-mm hammer-mill screen generated an average geometric mean particle size of 794 µm and the 6.0-mm screen a mean particle size of 1405 µm. However, hammer-mill screen size did not influence weight gain or FCR. The 6.0-mm screen size generated significantly higher starch and protein (N) digestibility coefficients in the distal jejunum and distal ileum than the 2.0-mm hammer-mill screen. 5. Tiger sorghum was superior to Block I sorghum, as significant advantages were observed for feed conversion ratios (3.25%), AME (0.37 MJ), ME:GE ratios (4.15%), AMEn (0.53 MJ), distal ileal starch digestibility coefficients (2.46%) and protein (N) digestibility coefficients in the distal jejunum (4.66%), proximal ileum (1.96%) and distal ileum (2.16%). The inferior Block I sorghum contained more kafirin (67.1 versus 51.3 g/kg), phytate (9.79 versus 8.40 g/kg), total phenolic compounds (4.68 versus 4.12 mg GAE/g), flavan-4-ols (7.98 versus 5.04 ABS/ml/g), total phenolic acids (554 versus 402 µg/g) and total ferulic acid (375 versus 281 µg/g) in comparison to Tiger sorghum.


Assuntos
Galinhas/fisiologia , Grão Comestível/fisiologia , Nutrientes/fisiologia , Sorghum/química , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Masculino , Tamanho da Partícula , Sorghum/genética
10.
Amino Acids ; 49(8): 1337-1345, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28474126

RESUMO

Fluid collected during sweating is enriched with amino acids derived from the skin's natural moisturising factors and has been termed "faux" sweat. Little is known about sex differences in sweat amino acid composition or whether faux sweat amino acid losses affect nitrogen balance. Faux sweat collected by healthy adults (n = 47) after exercise, and at rest by chronic fatigue patients, was analysed for amino acid composition. Healthy females had higher total amino acid concentrations in sweat (10.5 ± 1.2 mM) compared with healthy males (6.9 ± 0.9 mM). Females had higher levels of 13 amino acids in sweat including serine, alanine and glycine. Higher hydroxyproline and proline levels suggested greater collagen turnover in females. Modelling indicated that with conservative levels of exercise, amino acid losses in females via faux sweat were triple than those predicted for urine, whereas in males they were double. It was concluded that females were more susceptible to key amino acid loss during exercise and/or hot conditions. Females reporting chronic fatigue had higher levels of methionine in faux sweat than healthy females. Males reporting chronic fatigue had higher levels of numerous amino acids in faux sweat compared to healthy males. Higher amino acid loss in faux sweat associated with chronic fatigue could contribute to a hypometabolic state. Depending on activity levels, climatic conditions and gender, amino acid losses in sweat and skin leachate could influence daily protein turnover where periods of continuously high turnover could lead to a negative net nitrogen balance.


Assuntos
Aminoácidos/metabolismo , Colágeno/metabolismo , Exercício Físico/fisiologia , Síndrome de Fadiga Crônica/fisiopatologia , Nitrogênio/metabolismo , Suor/metabolismo , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Fatores Sexuais , Pele/metabolismo , Equilíbrio Hidroeletrolítico , Adulto Jovem
11.
Stat Med ; 36(12): 1989-2000, 2017 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-28226399

RESUMO

Mammography is routinely used to screen for breast cancer. However, the radiological interpretation of mammogram images is complicated by the heterogeneous nature of normal breast tissue and the fact that cancers are often of the same radiographic density as normal tissue. In this work, we use wavelets to quantify spectral slopes of breast cancer cases and controls and demonstrate their value in classifying images. In addition, we propose asymmetry statistics to be used in forming features, which improve the classification result. For the best classification procedure, we achieve approximately 77% accuracy (sensitivity=73%, specificity=84%) in classifying mammograms with and without cancer. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Análise de Ondaletas , Análise de Variância , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico , Estudos de Casos e Controles , Feminino , Humanos , Mamografia/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatística como Assunto
12.
BJOG ; 124(9): 1422-1429, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28176494

RESUMO

OBJECTIVE: Women with overactive bladder (OAB) often undergo urodynamics before invasive treatments are considered. Ultrasound measurement of bladder wall thickness (BWT) is a less invasive, less expensive and widely available test. It has the potential to diagnose the presence of detrusor overactivity (DO). We aimed to evaluate the accuracy of BWT in the diagnosis of DO. DESIGN: Prospective cohort study. SETTING: Twenty-two UK clinics (university and district general hospitals). METHODS: Consecutive eligible women with OAB symptoms had transvaginal ultrasound to estimate BWT (index test). The reference standard for the diagnosis of DO was urodynamic testing with multichannel subtracted cystometry. MAIN OUTCOME MEASURES: The sensitivity, specificity and likelihood ratios using a BWT threshold of ≥5 mm were used to indicate the presence of DO, and the area under the receiver operating characteristics (ROC) curve to give an overall estimate of BWT accuracy. RESULTS: Between March 2011 and 2013, 644/687 (94%) women recruited had both tests. The mean age was 52.7 years (standard deviation 13.9) and DO was diagnosed in 399/666 (60%) women. BWT had a sensitivity of 43% [95% confidence interval (CI) 38-48%], specificity of 62% (95% CI 55-68%), and likelihood ratios of 1.11 (95% CI 0.92-1.35) and 0.93 (95% CI 0.82-1.06) for positive and negative tests, respectively. The area under the ROC curve was 0.53 (95% CI 0.48-0.57). Extensive sensitivity analyses and subgroup analyses were carried out, but did not alter the interpretation. CONCLUSIONS: BWT is not a good replacement test for urodynamics in women with overactive bladder. TWEETABLE ABSTRACT: Bladder wall thickness is not a good replacement test for urodynamics in women with overactive bladder.


Assuntos
Bexiga Urinária Hiperativa/diagnóstico por imagem , Bexiga Urinária/diagnóstico por imagem , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade , Método Simples-Cego , Ultrassonografia , Bexiga Urinária/patologia , Urodinâmica
13.
Nutr J ; 16(1): 19, 2017 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-28330481

RESUMO

BACKGROUND: The excretion of amino acids in urine represents an important avenue for the loss of key nutrients. Some amino acids such as glycine and histidine are lost in higher abundance than others. These two amino acids perform important physiological functions and are required for the synthesis of key proteins such as haemoglobin and collagen. METHODS: Stage 1 of this study involved healthy subjects (n = 151) who provided first of the morning urine samples and completed symptom questionnaires. Urine was analysed for amino acid composition by gas chromatography. Stage 2 involved a subset of the initial cohort (n = 37) who completed a 30 day trial of an amino acid supplement and subsequent symptom profile evaluation. RESULTS: Analyses of urinary amino acid profiles revealed that three groups could be objectively defined from the 151 participants using k-means clustering. The amino acid profiles were significantly different between each of the clusters (Wilks' Lambda = 0.13, p < 0.0001). Cluster 1 had the highest loss of amino acids with histidine being the most abundant component. Cluster 2 had glycine present as the most abundant urinary amino acid and cluster 3 had equivalent abundances of glycine and histidine. Strong associations were observed between urinary proline concentrations and fatigue/pain scores (r = .56 to .83) for females in cluster 1, with several other differential sets of associations observed for the other clusters. CONCLUSIONS: Different phenotypic subsets exist in the population based on amino acid excretion characteristics found in urine. Provision of the supplement resulted in significant improvements in reported fatigue and sleep for 81% of the trial cohort with all females reporting improvements in fatigue. TRIAL REGISTRATION: The study was registered on the 18th April 2011 with the Australian New Zealand Clinical Trials Registry ( ACTRN12611000403932 ).


Assuntos
Aminoácidos/administração & dosagem , Aminoácidos/urina , Suplementos Nutricionais , Fadiga/tratamento farmacológico , Adolescente , Adulto , Índice de Massa Corporal , Análise por Conglomerados , Estudos de Coortes , Feminino , Humanos , Masculino , Nova Zelândia , Inquéritos e Questionários , Adulto Jovem
14.
Eur J Dent Educ ; 21(4): e89-e100, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27440069

RESUMO

INTRODUCTION: Dental professionalism is an essential requirement to practice dentistry that covers both abilities and personal qualities. Therefore, a programme of assessment that promotes personal and professional development throughout the undergraduate dental education course is needed. This study aimed to develop and validate a system to assess dental students' professionalism based on a previously developed conceptual framework. METHODS: Using the framework, an assessment programme was designed to encourage students to reflect on and explain their observed behaviours with appropriate feedback. The programme was panel-tested and then administered to a cohort of senior dental students. Internal reliability criterion validity and construct validity were evaluated quantitatively, whilst the usefulness of the programme was evaluated qualitatively. RESULTS: Mean of student, staff and agreed grades was similar, and there were no floor or ceiling effects. All item-total correlations were >0.6 and Cronbach's alpha = 0.95 indicating acceptable internal reliability. All items correlated significantly with global ratings indicating good criterion validity. All hypothesized correlations were significant, and grades were not related to age or gender. Qualitative data produced three themes: assessment process, educational value and suggestions for improvement. CONCLUSION: The assessment programme has good internal reliability and validity and suggests that basing an assessment system around the explicit theoretical model is a valuable educational tool.


Assuntos
Educação em Odontologia , Profissionalismo , Estudantes de Odontologia/psicologia , Adulto , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Adulto Jovem
15.
BJOG ; 123(4): 625-31, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26011792

RESUMO

OBJECTIVES: To undertake a cost-effectiveness analysis of outpatient uterine polypectomy compared with standard inpatient treatment under general anaesthesia. DESIGN: Economic evaluation carried out alongside the multi-centre, pragmatic, non-inferiority, randomised controlled Outpatient Polyp Treatment (OPT) trial. The UK National Health Service (NHS) perspective was used in the estimation of costs and the interpretation of results. SETTING: Thirty-one secondary care UK NHS hospitals between April 2008 and July 2011. PARTICIPANTS: Five hundred and seven women with abnormal uterine bleeding and hysteroscopically diagnosed endometrial polyps. INTERVENTIONS: Outpatient uterine polypectomy versus standard inpatient treatment. Clinicians were free to choose the technique for polypectomy within the allocated setting. MAIN OUTCOME MEASURES: Patient-reported effectiveness of the procedure determined by the women's self-assessment of bleeding at 6 months, and QALY gains at 6 and 12 months. RESULTS: Inpatient treatment was slightly more effective but more expensive than outpatient treatment, resulting in relatively high incremental cost-effectiveness ratios. Intention-to-treat analysis of the base case at 6 months revealed that it cost an additional £9421 per successfully treated patient in the inpatient group and £ 1,099,167 per additional QALY gained, when compared with outpatient treatment. At 12 months, these costs were £22,293 per additional effectively treated patient and £445,867 per additional QALY gained, respectively. CONCLUSIONS: Outpatient treatment of uterine polyps associated with abnormal uterine bleeding appears to be more cost-effective than inpatient treatment at willingness-to-pay thresholds acceptable to the NHS. TWEETABLE ABSTRACT: HTA-funded OPT trial concluded that outpatient uterine polypectomy is cost-effective compared with inpatient polypectomy.


Assuntos
Assistência Ambulatorial/economia , Procedimentos Cirúrgicos em Ginecologia/economia , Custos de Cuidados de Saúde , Pacientes Internados , Pacientes Ambulatoriais , Pólipos/economia , Hemorragia Uterina/economia , Assistência Ambulatorial/estatística & dados numéricos , Pesquisa Comparativa da Efetividade , Custos e Análise de Custo , Feminino , Hospitalização/economia , Hospitalização/estatística & dados numéricos , Humanos , Preferência do Paciente , Pólipos/complicações , Pólipos/cirurgia , Resultado do Tratamento , Reino Unido/epidemiologia , Hemorragia Uterina/etiologia , Hemorragia Uterina/cirurgia
16.
Neuroimage ; 86: 1-9, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23707581

RESUMO

(1)H magnetic resonance spectroscopy ((1)H MRS) and spectral editing methods, such as MEGA-PRESS, allow researchers to investigate metabolite and neurotransmitter concentrations in-vivo. Here we address the utilization of (1)H MRS for the investigation of GABA concentrations in the ASD brain, in three locations; motor, visual and auditory areas. An initial repeatability study (5 subjects, 5 repeated measures separated by ~5days on average) indicated no significant effect of reference metabolite choice on GABA quantitation (p>0.6). Coefficients of variation for GABA+/NAA, GABA+/Cr and GABA+/Glx were all of the order of 9-11%. Based on these findings, we investigated creatine-normalized GABA+ ratios (GABA+/Cr) in a group of (N=17) children with autism spectrum disorder (ASD) and (N=17) typically developing children (TD) for Motor, Auditory and Visual regions of interest (ROIs). Linear regression analysis of gray matter (GM) volume changes (known to occur with development) revealed a significant decrease of GM volume with Age for Motor (F(1,30)=17.92; p<0.001) and Visual F(1,16)=14.41; p<0.005 but not the Auditory ROI (p=0.55). Inspection of GABA+/Cr changes with Age revealed a marginally significant change for the Motor ROI only (F(1,30)=4.11; p=0.054). Subsequent analyses were thus conducted for each ROI separately using Age and GM volume as covariates. No group differences in GABA+/Cr were observed for the Visual ROI between TD vs. ASD children. However, the Motor and Auditory ROI showed significantly reduced GABA+/Cr in ASD (Motor p<0.05; Auditory p<0.01). The mean deficiency in GABA+/Cr from the Motor ROI was approximately 11% and Auditory ROI was approximately 22%. Our novel findings support the model of regional differences in GABA+/Cr in the ASD brain, primarily in Auditory and to a lesser extent Motor but not Visual areas.


Assuntos
Córtex Cerebral/metabolismo , Transtornos Globais do Desenvolvimento Infantil/metabolismo , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Neurotransmissores/metabolismo , Ácido gama-Aminobutírico/metabolismo , Adulto , Criança , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Distribuição Tecidual
17.
Br J Cancer ; 110(12): 2837-46, 2014 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-24867697

RESUMO

BACKGROUND: The purpose of this study was to determine the accuracy of sentinel lymph node (SLN) biopsy with technetium 99 (99mTc) and/or blue dye-enhanced lymphoscintigraphy in vulval cancer. METHODS: Sensitive searches of databases were performed upto October 2013. Studies with at least 75% of women with FIGO stage IB or II vulval cancer evaluating SLN biopsy with 99mTc, blue dye or both with reference standard of inguinofemoral lymphadenectomy (IFL) or clinical follow-up were included. Meta-analyses were performed using Meta-Disc version 1.4. RESULTS: Of the 2950 references, 29 studies (1779 women) were included; most of them evaluated 99mTc combined with blue dye. Of these, 24 studies reported results for SLN followed by IFL, and 5 reported clinical follow-up only for SLN negatives. Pooling of all studies was inappropriate because of heterogeneity. Mean SLN detection rates were 94.0% for 99mTc, 68.7% for blue dye and 97.7% for both. SLN biopsy had pooled sensitivity of 95% (95% CI 92-98%) with negative predictive value (NPV) of 97.9% in studies using 99mTc/blue dye, ultrastaging and immunohistochemistry with IFL as reference. Pooled sensitivity for SLN with clinical follow-up for SLN-negatives was 91% (85-95%) with NPV 95.6%. Patients undergoing SLN biopsy experienced less morbidity than those undergoing IFL. CONCLUSIONS: Sentinel lymph node biopsy using 99mTC, blue dye and ultrastaging with immunohistochemistry is highly accurate when restricted to carefully selected patients, within a rigorous protocol, with close follow-up and where sufficient numbers for learning curve optimisation exist. Patients must make an informed choice between the slightly higher groin recurrence rates of SLN biopsy vs the greater morbidity of IFL.


Assuntos
Linfonodos/patologia , Biópsia de Linfonodo Sentinela , Neoplasias Vulvares/patologia , Corantes , Detecção Precoce de Câncer , Feminino , Humanos , Imuno-Histoquímica , Linfonodos/diagnóstico por imagem , Linfonodos/cirurgia , Metástase Linfática , Linfocintigrafia , Recidiva Local de Neoplasia , Compostos Radiofarmacêuticos , Coloração e Rotulagem , Tecnécio , Neoplasias Vulvares/diagnóstico por imagem
18.
J Clin Microbiol ; 52(7): 2680-3, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24808242

RESUMO

Dientamoeba fragilis is a common enteropathogen of humans. Recently a cyst stage of the parasite was described in an animal model; however, no cyst stage has been described in detail from clinical samples. We describe both cyst and precystic forms from human clinical samples.


Assuntos
Dientamoeba/citologia , Dientamebíase/parasitologia , Esporos de Protozoários/citologia , Dientamoeba/fisiologia , Humanos , Microscopia , Esporos de Protozoários/fisiologia
19.
BJOG ; 121(4): 464-76, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24299112

RESUMO

OBJECTIVE: To undertake a cost-effectiveness analysis that compares positron emission tomography - computed tomography (PET-CT) imaging plus standard practice with standard practice alone in the diagnosis of recurrent or persistent cervical cancer during routine surveillance and follow-up of women who have previously been diagnosed and treated. DESIGN: Model-based economic evaluation using data from a systematic review, supplemented with data from other sources, and taking a UK National Health Service (NHS) perspective. SETTING: Secondary Care in England. POPULATION: Women at least 3 months after the completion of treatment, with either recurrent or persistent cervical cancer. METHODS: A state transition (Markov) model was developed using TreeAge Pro 2011. The structure of the model was informed by the reviews of the trials and clinical input. In the model, two diagnostic strategies were examined. A one-way sensitivity analysis, probabilistic sensitivity analysis, and a value of information analysis were also carried out. MAIN OUTCOME MEASURES: Cost-effectiveness based on incremental cost per quality-adjusted life year (QALY). RESULTS: Adding PET-CT to the current treatment strategy of clinical examination and scanning [magnetic resonance imaging (MRI) and/or CT scan] during the routine surveillance and follow-up of women with recurrent or persistent cervical cancer is significantly more costly, with only a minimal increase in effectiveness. The incremental cost-effectiveness ratio (ICER) for the strategy of PET-CT as an adjunct to the standard treatment strategy that included clinical examination, MRI, and/or CT scan, compared with the usual treatment alone, was over £1 million per QALY. CONCLUSION: The results of the current analysis suggest that use of PET-CT in the diagnosis of recurrent or persistent cervical cancer is not cost-effective. Current guidelines recommending imaging using PET-CT as a diagnostic or surveillance tool need to be reconsidered in light of these results. This study did not specifically investigate the use of PET-CT in women with symptoms and radiological suspicion of recurrence where exenteration was considered. More research in that specific area is required.


Assuntos
Recidiva Local de Neoplasia/diagnóstico , Tomografia por Emissão de Pósitrons/economia , Tomografia Computadorizada por Raios X/economia , Neoplasias do Colo do Útero/diagnóstico , Quimiorradioterapia Adjuvante , Análise Custo-Benefício , Técnicas de Apoio para a Decisão , Feminino , Humanos , Histerectomia , Imageamento por Ressonância Magnética/economia , Cadeias de Markov , Modelos Econômicos , Recidiva Local de Neoplasia/economia , Recidiva Local de Neoplasia/mortalidade , Anos de Vida Ajustados por Qualidade de Vida , Medicina Estatal/economia , Taxa de Sobrevida , Reino Unido , Neoplasias do Colo do Útero/economia , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/terapia
20.
BJOG ; 121(4): 398-407, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24299154

RESUMO

BACKGROUND: Positron emission tomography-computed tomography (PET-CT) is recommended to triage women for exenterative surgery and surveillance after treatment for advanced cervical cancer. OBJECTIVE: To evaluate diagnostic accuracy of additional whole body PET-CT compared with CT/magnetic resonance imaging (MRI) alone in women with suspected recurrent/persistent cervical cancer and in asymptomatic women as surveillance. DESIGN: Systematic reviews. Subjective elicitation to supplement diagnostic information. SEARCH STRATEGY/SELECTION CRITERIA/DATA COLLECTION AND ANALYSIS: Searches of electronic databases were performed to June 2013. Studies in women with suspected recurrent/persistent cervical cancer and in asymptomatic women undergoing follow up with sufficient numeric data were included. We calculated sensitivity, specificity and corresponding 95% confidence intervals. Meta-analyses employed a bivariate model that included a random-effects term for between-study variations (CT studies) and univariate random effects meta-analyses (PET-CT studies) for sensitivity and specificity separately. SUBJECTIVE ELICITATION: Prevalence of recurrence and the accuracy of imaging elicited using the allocation of points technique. Coherence of elicited subjective probabilities with estimates in the literature examined. RESULTS: We identified 15 relevant studies; none directly compared additional PET-CT with MRI or CT separately. Most CT and MRI studies used older protocols and the majority did not distinguish between asymptomatic and symptomatic women. Meta-analysis of nine PET-CT studies in mostly symptomatic women showed sensitivity of 94.8 (95% CI 91.2-96.9), and specificity of 86.9% (95% CI 82.2-90.5). The summary estimate of the sensitivity of CT for detection of recurrence was 89.64% (95% CI 81.59-94.41) and specificity was 76% (95% CI 43.68-92.82). Meta-analysis for MRI test accuracy studies was not possible because of clinical heterogeneity. The sensitivity and specificity of MRI in pelvic recurrence varied between 82 and 100% and between 78 and 100%, respectively. Formal statistical comparisons of the accuracy of index tests were not possible. Subjective elicitation provided estimates comparable to the literature. Subjective estimates of the increase in accuracy from the addition of PET-CT were less than elicited increases required to justify the use in PET-CT for surveillance. CONCLUSION: Evidence to support additional PET-CT is scarce, of average quality and does not distinguish between application for surveillance and diagnosis. Guidelines recommending PET-CT in recurrent cervical cancer need to be reconsidered in the light of the existing evidence base.


Assuntos
Recidiva Local de Neoplasia/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Modelos Estatísticos , Sensibilidade e Especificidade
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