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1.
J Neurosci ; 42(21): 4394-4400, 2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35501156

RESUMO

Emotion recognition abilities are fundamental to our everyday social interaction. A large number of clinical populations show impairments in this domain, with emotion recognition atypicalities being particularly prevalent among disorders exhibiting a dopamine system disruption (e.g., Parkinson's disease). Although this suggests a role for dopamine in emotion recognition, studies employing dopamine manipulation in healthy volunteers have exhibited mixed neural findings and no behavioral modulation. Interestingly, while a dependence of dopaminergic drug effects on individual baseline dopamine function has been well established in other cognitive domains, the emotion recognition literature so far has failed to account for these possible interindividual differences. The present within-subjects study therefore tested the effects of the dopamine D2 antagonist haloperidol on emotion recognition from dynamic, whole-body stimuli while accounting for interindividual differences in baseline dopamine. A total of 33 healthy male and female adults rated emotional point-light walkers (PLWs) once after ingestion of 2.5 mg haloperidol and once after placebo. To evaluate potential mechanistic pathways of the dopaminergic modulation of emotion recognition, participants also performed motoric and counting-based indices of temporal processing. Confirming our hypotheses, effects of haloperidol on emotion recognition depended on baseline dopamine function, where individuals with low baseline dopamine showed enhanced, and those with high baseline dopamine decreased emotion recognition. Drug effects on emotion recognition were related to drug effects on movement-based and explicit timing mechanisms, indicating possible mediating effects of temporal processing. Results highlight the need for future studies to account for baseline dopamine and suggest putative mechanisms underlying the dopaminergic modulation of emotion recognition.SIGNIFICANCE STATEMENT A high prevalence of emotion recognition difficulties among clinical conditions where the dopamine system is affected suggests an involvement of dopamine in emotion recognition processes. However, previous psychopharmacological studies seeking to confirm this role in healthy volunteers thus far have failed to establish whether dopamine affects emotion recognition and lack mechanistic insights. The present study uncovered effects of dopamine on emotion recognition in healthy individuals by controlling for interindividual differences in baseline dopamine function and investigated potential mechanistic pathways via which dopamine may modulate emotion recognition. Our findings suggest that dopamine may influence emotion recognition via its effects on temporal processing, providing new directions for future research on typical and atypical emotion recognition.


Assuntos
Dopamina , Haloperidol , Adulto , Dopamina/metabolismo , Antagonistas dos Receptores de Dopamina D2/farmacologia , Emoções , Feminino , Haloperidol/farmacologia , Humanos , Masculino , Percepção
2.
Phys Rev Lett ; 130(10): 105102, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36962058

RESUMO

Helium ash alpha particles at ∼100 keV in magnetically confined fusion plasmas may have the same Larmor radius, as well as cyclotron frequency, as the energetic beam-injected deuterons that heat the plasma. While the velocity-space distribution of the helium ash is monotonically decreasing, that of the energetic deuterons is a delta function in the edge plasma. Here we identify, by means of first principles particle-in-cell computations, a new physical process by which Larmor radius matching enables collective gyroresonant energy transfer between these two colocated minority energetic ion populations, embedded in majority thermal plasma. This newly identified nonlinear phenomenon rests on similar underlying physics to widely observed ion cyclotron emission from suprathermal minority ion populations.

3.
Ann Oncol ; 33(12): 1318-1327, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36122798

RESUMO

BACKGROUND: Breast cancer has a significant heritable basis, of which ∼60% remains unexplained. Testing for BRCA1/BRCA2 offers useful discrimination of breast cancer risk within families, and identification of additional breast cancer susceptibility genes could offer clinical utility. PATIENTS AND METHODS: We included 2135 invasive breast cancer cases recruited via the Breast and Ovarian Cancer Susceptibility study, a retrospective UK study of familial breast cancer. ELIGIBILITY CRITERIA: female, BRCA-negative, white European ethnicity, and one of: (i) breast cancer family history, (ii) bilateral disease, (iii) young age of onset (<30 years), and (iv) concomitant ovarian cancer. We undertook exome sequencing of cases and carried out gene-level burden testing of rare damaging variants against those from 51 377 ethnicity-matched population controls from gnomAD. RESULTS: 159/2135 (7.4%) cases had a qualifying variant in an established breast cancer susceptibility gene, with minimal evidence of signal in other cancer susceptibility genes. Known breast cancer susceptibility genes PALB2, CHEK2, and ATM were the only genes to retain statistical significance after correcting for multiple testing. Due to the enrichment of hereditary cases in the series, we had good power (>80%) to detect a gene of BRCA1-like risk [odds ratio (OR) = 10.6] down to a population minor allele frequency of 4.6 × 10-5 (1 in 10 799, less than one-tenth that of BRCA1)and of PALB2-like risk (OR = 5.0) down to a population minor allele frequency of 2.8 × 10-4 (1 in 1779, less than half that of PALB2). Power was lower for identification of novel moderate penetrance genes (OR = 2-3) like CHEK2 and ATM. CONCLUSIONS: This is the largest case-control whole-exome analysis of enriched breast cancer published to date. Whilst additional breast cancer susceptibility genes likely exist, those of high penetrance are likely to be of very low mutational frequency. Contention exists regarding the clinical utility of such genes.


Assuntos
Neoplasias da Mama , Neoplasias Ovarianas , Neoplasias de Mama Triplo Negativas , Feminino , Humanos , Adulto , Mutação em Linhagem Germinativa , Neoplasias da Mama/genética , Neoplasias da Mama/diagnóstico , Estudos Retrospectivos , Predisposição Genética para Doença , Neoplasias Ovarianas/genética
4.
Nature ; 539(7627): 65-68, 2016 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-27626378

RESUMO

A unique feature of Pluto's large satellite Charon is its dark red northern polar cap. Similar colours on Pluto's surface have been attributed to tholin-like organic macromolecules produced by energetic radiation processing of hydrocarbons. The polar location on Charon implicates the temperature extremes that result from Charon's high obliquity and long seasons in the production of this material. The escape of Pluto's atmosphere provides a potential feedstock for a complex chemistry. Gas from Pluto that is transiently cold-trapped and processed at Charon's winter pole was proposed as an explanation for the dark coloration on the basis of an image of Charon's northern hemisphere, but not modelled quantitatively. Here we report images of the southern hemisphere illuminated by Pluto-shine and also images taken during the approach phase that show the northern polar cap over a range of longitudes. We model the surface thermal environment on Charon and the supply and temporary cold-trapping of material escaping from Pluto, as well as the photolytic processing of this material into more complex and less volatile molecules while cold-trapped. The model results are consistent with the proposed mechanism for producing the observed colour pattern on Charon.

5.
J Dairy Sci ; 104(8): 9093-9105, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33934871

RESUMO

The purpose of this study was to evaluate the effect of rumination times and days spent in a close-up group before calving (DCU) on early-lactation health and reproductive outcomes in dairy cows. Data were gathered for 719 cows located in a single herd. Herd management and reproductive records were analyzed for cows receiving treatment in the first 30 d of lactation (days in milk; DIM) for clinical mastitis, reproductive tract disease, ketosis, milk fever, and displaced abomasum. Rumination times for each cow were downloaded daily from the herd's automated collar system used to generate heat and health alerts for each cow beginning at 21 d precalving until 14 d postcalving. During the first 30 DIM, 121 cows (18%) developed at least 1 disease-any combination of ketosis (40 cows, 5.9% of total), mastitis (17 cows, 2.5%), metritis (75 cows, 11%), milk fever (17 cows, 2.5%), or displaced abomasum (28 cows, 4.1%); 305 cows (45%) were pregnant again at 100 DIM, and an additional 139 cows (20%) were pregnant at 150 DIM. Principal component analysis was used to determine the relationship between gestation length and DCU and their association with the odds of developing disease in early lactation. We did not find any significant association between precalving rumination time and disease within the first 30 DIM. Higher rumination time in the week before calving was shown to be strongly linked to a shorter time to subsequent pregnancy, whereas rumination times postcalving were not associated with changes in the time to pregnancy. Principal component analysis showed that a curvilinear combination of gestation length and DCU (principal component 1) was significantly associated with changes in disease incidence in the first 30 DIM. Gestation length and time spent in close up are important management factors in reducing the incidence of disease in early lactation, and rumination times around calving may help predict future reproductive outcomes.


Assuntos
Doenças dos Bovinos , Cetose , Animais , Bovinos , Feminino , Cetose/veterinária , Lactação , Leite , Período Pós-Parto , Gravidez , Resultado da Gravidez
6.
Br J Surg ; 107(9): 1114-1122, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32187680

RESUMO

BACKGROUND: Placebo-controlled trials play an important role in the evaluation of healthcare interventions. However, they can be challenging to design and deliver for invasive interventions, including surgery. In-depth understanding of the component parts of the treatment intervention is needed to ascertain what should, and should not, be delivered as part of the placebo. Assessment of risk to patients and strategies to ensure that the placebo effectively mimics the treatment are also required. To date, no guidance exists for the design of invasive placebo interventions. This study aimed to develop a framework to optimize the design and delivery of invasive placebo interventions in RCTs. METHODS: A preliminary framework was developed using published literature to: expand the scope of an existing typology, which facilitates the deconstruction of invasive interventions; and identify placebo optimization strategies. The framework was refined after consultation with key stakeholders in surgical trials, consensus methodology and medical ethics. RESULTS: The resulting DITTO framework consists of five stages: deconstruct treatment intervention into constituent components and co-interventions; identify critical surgical element(s); take out the critical element(s); think risk, feasibility and role of placebo in the trial when considering remaining components; and optimize placebo to ensure effective blinding of patients and trial personnel. CONCLUSION: DITTO considers invasive placebo composition systematically, accounting for risk, feasibility and placebo optimization. Use of the framework can support the design of high-quality RCTs, which are needed to underpin delivery of healthcare interventions.


ANTECEDENTES: Los ensayos controlados con placebo juegan un papel importante en la evaluación de las intervenciones sanitarias. Sin embargo, pueden ser difíciles de diseñar e implementar en el caso de intervenciones invasivas, incluida la cirugía. Se necesita un conocimiento profundo de los componentes de la intervención terapéutica (para determinar qué se debe y qué no se debe administrar como parte del placebo). También se precisa de una evaluación del riesgo para los pacientes y de las estrategias para garantizar que el placebo imite el tratamiento de forma efectiva. Hasta la fecha no existen guías para el diseño de intervenciones invasivas con placebo. Este estudio tuvo como objetivo desarrollar un marco para optimizar el diseño y la práctica de intervenciones invasivas con placebo dentro en los ensayos clínicos aleatorizados (ECA). MÉTODOS: Utilizando la literatura publicada, se desarrolló un marco preliminar para i) ampliar el alcance de los modelos existentes para facilitar la deconstrucción de las actuaciones invasivas, y ii) identificar estrategias para optimizar el placebo. El marco se perfeccionó tras consultar con partes interesadas ​​en ensayos quirúrgicos, metodología de consenso y ética médica. RESULTADOS: El marco DITTO resultantes consiste en cinco etapas: Etapa 1: deconstrucción de la intervención de tratamiento en sus componentes esenciales y co-intervenciones; Etapa 2: identificar el(los) elemento(s) quirúrgico(s) básico(s); Etapa 3: eliminar el(los) elemento(s) básico(s); Etapa 4: considerar el riesgo, la viabilidad y el papel del placebo en el ensayo al tener en cuenta los demás componentes; y Etapa 5: optimizar el placebo para garantizar el cegamiento efectivo de los pacientes y del personal del ensayo. CONCLUSIÓN: DITTO considera de forma sistemática la naturaleza invasiva del placebo, teniendo en cuenta el riesgo, la viabilidad y la optimización del placebo. El uso de este marco de referencia puede ayudar al diseño de ECAs de alta calidad, necesarios para afianzar la implementación de intervenciones sanitarias.


Assuntos
Placebos/normas , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Medição de Risco
7.
Nature ; 516(7530): 254-8, 2014 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-25274307

RESUMO

Germinal centre B-cell-like diffuse large B-cell lymphoma (GCB-DLBCL) is a common malignancy, yet the signalling pathways that are deregulated and the factors leading to its systemic dissemination are poorly defined. Work in mice showed that sphingosine-1-phosphate receptor-2 (S1PR2), a Gα12 and Gα13 coupled receptor, promotes growth regulation and local confinement of germinal centre B cells. Recent deep sequencing studies of GCB-DLBCL have revealed mutations in many genes in this cancer, including in GNA13 (encoding Gα13) and S1PR2 (refs 5,6, 7). Here we show, using in vitro and in vivo assays, that GCB-DLBCL-associated mutations occurring in S1PR2 frequently disrupt the receptor's Akt and migration inhibitory functions. Gα13-deficient mouse germinal centre B cells and human GCB-DLBCL cells were unable to suppress pAkt and migration in response to S1P, and Gα13-deficient mice developed germinal centre B-cell-derived lymphoma. Germinal centre B cells, unlike most lymphocytes, are tightly confined in lymphoid organs and do not recirculate. Remarkably, deficiency in Gα13, but not S1PR2, led to germinal centre B-cell dissemination into lymph and blood. GCB-DLBCL cell lines frequently carried mutations in the Gα13 effector ARHGEF1, and Arhgef1 deficiency also led to germinal centre B-cell dissemination. The incomplete phenocopy of Gα13- and S1PR2 deficiency led us to discover that P2RY8, an orphan receptor that is mutated in GCB-DLBCL and another germinal centre B-cell-derived malignancy, Burkitt's lymphoma, also represses germinal centre B-cell growth and promotes confinement via Gα13. These findings identify a Gα13-dependent pathway that exerts dual actions in suppressing growth and blocking dissemination of germinal centre B cells that is frequently disrupted in germinal centre B-cell-derived lymphoma.


Assuntos
Linfócitos B/metabolismo , Linfócitos B/patologia , Subunidades alfa G12-G13 de Proteínas de Ligação ao GTP/metabolismo , Centro Germinativo/patologia , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Transdução de Sinais , Animais , Sangue/imunologia , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Humanos , Linfa/citologia , Linfoma Difuso de Grandes Células B/genética , Camundongos , Camundongos Endogâmicos C57BL , Mutação/genética , Proteína Oncogênica v-akt/genética , Proteína Oncogênica v-akt/metabolismo , Receptores de Lisoesfingolipídeo/deficiência , Receptores de Lisoesfingolipídeo/genética , Receptores de Lisoesfingolipídeo/metabolismo , Receptores Purinérgicos P2Y/genética , Receptores Purinérgicos P2Y/metabolismo , Fatores de Troca de Nucleotídeo Guanina Rho/deficiência , Fatores de Troca de Nucleotídeo Guanina Rho/genética , Receptores de Esfingosina-1-Fosfato
8.
BMC Med ; 17(1): 14, 2019 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-30665398

RESUMO

BACKGROUND: Substantial global progress in the control of malaria in recent years has led to increased commitment to its potential elimination. Whether this is possible in high transmission areas of sub-Saharan Africa remains unclear. Zanzibar represents a unique case study of such attempt, where modern tools and strategies for malaria treatment and vector control have been deployed since 2003. METHODS: We have studied temporal trends of comprehensive malariometric indices in two districts with over 100,000 inhabitants each. The analyses included triangulation of data from annual community-based cross-sectional surveys, health management information systems, vital registry and entomological sentinel surveys. RESULTS: The interventions, with sustained high-community uptake, were temporally associated with a major malaria decline, most pronounced between 2004 and 2007 and followed by a sustained state of low transmission. In 2015, the Plasmodium falciparum community prevalence of 0.43% (95% CI 0.23-0.73) by microscopy or rapid diagnostic test represented 96% reduction compared with that in 2003. The P. falciparum and P. malariae prevalence by PCR was 1.8% (95% CI 1.3-2.3), and the annual P. falciparum incidence was estimated to 8 infections including 2.8 clinical episodes per 1000 inhabitants. The total parasite load decreased over 1000-fold (99.9%) between 2003 and 2015. The incidence of symptomatic malaria at health facilities decreased by 94% with a trend towards relatively higher incidence in age groups > 5 years, a more pronounced seasonality and with reported travel history to/from Tanzania mainland as a higher risk factor. All-cause mortality among children < 5 years decreased by 72% between 2002 and 2007 mainly following the introduction of artemisinin-based combination therapies whereas the main reduction in malaria incidence followed upon the vector control interventions from 2006. Human biting rates decreased by 98% with a major shift towards outdoor biting by Anopheles arabiensis. CONCLUSIONS: Zanzibar provides new evidence of the feasibility of reaching uniquely significant and sustainable malaria reduction (pre-elimination) in a previously high endemic region in sub-Saharan Africa. The data highlight constraints of optimistic prognostic modelling studies. New challenges, mainly with outdoor transmission, a large asymptomatic parasite reservoir and imported infections, require novel tools and reoriented strategies to prevent a rebound effect and achieve elimination.


Assuntos
Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Malária Falciparum/transmissão , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Incidência , Lactente , Masculino , Prevalência , Tanzânia/epidemiologia
9.
Mol Psychiatry ; 23(2): 384-391, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28322281

RESUMO

Current pharmacotherapies for depression exhibit slow onset, side effects and limited efficacy. Therefore, identification of novel fast-onset antidepressants is desirable. GLO1 is a ubiquitous cellular enzyme responsible for the detoxification of the glycolytic byproduct methylglyoxal (MG). We have previously shown that MG is a competitive partial agonist at GABA-A receptors. We examined the effects of genetic and pharmacological inhibition of GLO1 in two antidepressant assay models: the tail suspension test (TST) and the forced swim test (FST). We also examined the effects of GLO1 inhibition in three models of antidepressant onset: the chronic FST (cFST), chronic mild stress (CMS) paradigm and olfactory bulbectomy (OBX). Genetic knockdown of Glo1 or pharmacological inhibition using two structurally distinct GLO1 inhibitors (S-bromobenzylglutathione cyclopentyl diester (pBBG) or methyl-gerfelin (MeGFN)) reduced immobility in the TST and acute FST. Both GLO1 inhibitors also reduced immobility in the cFST after 5 days of treatment. In contrast, the serotonin reuptake inhibitor fluoxetine (FLX) reduced immobility after 14, but not 5 days of treatment. Furthermore, 5 days of treatment with either GLO1 inhibitor blocked the depression-like effects induced by CMS on the FST and coat state, and attenuated OBX-induced locomotor hyperactivity. Finally, 5 days of treatment with a GLO1 inhibitor (pBBG), but not FLX, induced molecular markers of the antidepressant response including brain-derived neurotrophic factor (BDNF) induction and increased phosphorylated cyclic-AMP response-binding protein (pCREB) to CREB ratio in the hippocampus and medial prefrontal cortex (mPFC). Our findings indicate that GLO1 inhibitors may provide a novel and fast-acting pharmacotherapy for depression.


Assuntos
Lactoilglutationa Liase/antagonistas & inibidores , Lactoilglutationa Liase/fisiologia , Aldeído Pirúvico/farmacologia , Animais , Antidepressivos/farmacologia , Depressão/tratamento farmacológico , Depressão/metabolismo , Transtorno Depressivo/tratamento farmacológico , Transtorno Depressivo/metabolismo , Feminino , GABAérgicos/farmacologia , Elevação dos Membros Posteriores , Hipocampo/efeitos dos fármacos , Lactoilglutationa Liase/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Córtex Pré-Frontal/efeitos dos fármacos , Natação
10.
Qual Life Res ; 28(2): 335-343, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30229533

RESUMO

PURPOSE: The Western Ontario and McMaster Universities Arthritis Index (WOMAC) is a commonly used outcome measure for osteoarthritis. There are different versions of the WOMAC (Likert, visual analogue or numeric scales). A previous review of trials published before 2010 found poor reporting and inconsistency in how the WOMAC was used. This review explores whether these problems persist. METHODS: This systematic review included randomised trials of hip and/or knee osteoarthritis published in 2016 that used the WOMAC. Data were extracted on the version used, score range, analysis and results of the WOMAC, and whether these details were clearly reported. RESULTS: This review included 62 trials and 41 reported the WOMAC total score. The version used and item range for the WOMAC total score were unclear in 44% (n = 18/41) and 24% (n = 10/41) of trials, respectively. The smallest total score range was 0-10 (calculated by averaging 24 items scored 0-10); the largest was 0-2400 (calculated by summing 24 items scored 0-100). All trials reported the statistical analysis methods but only 29% reported the between-group mean difference and 95% confidence interval. CONCLUSION: Details on the use and scoring of the WOMAC were often not reported. We recommend that trials report the version of the WOMAC and the score range used. The between-group treatment effect and corresponding confidence interval should be reported. If all the items of the WOMAC are collected, the total score and individual subscale scores should be presented. Better reporting would facilitate the interpretation, comparison and synthesis of the WOMAC score in trials.


Assuntos
Osteoartrite do Quadril/diagnóstico , Osteoartrite do Joelho/diagnóstico , Qualidade de Vida/psicologia , Feminino , Humanos , Masculino , Ontário , Avaliação de Resultados em Cuidados de Saúde
11.
BMC Evol Biol ; 18(1): 193, 2018 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-30547744

RESUMO

BACKGROUND: Obligate pollination mutualisms (OPMs) are specialized interactions in which female pollinators transport pollen between the male and female flowers of a single plant species and then lay eggs into those same flowers. The pollinator offspring hatch and feed upon some or all of the developing ovules pollinated by their mothers. Strong trait matching between plants and their pollinators in OPMs is expected to result in reciprocal partner specificity i.e., a single pollinator species using a single plant species and vice versa, and strict co-speciation. These issues have been studied extensively in figs and fig wasps, but little in the more recently discovered co-diversification of Epicephala moths and their Phyllanthaceae hosts. OPMs involving Epicephala moths are believed occur in approximately 500 species of Phyllanthaceae, making it the second largest OPM group after the Ficus radiation (> 750 species). In this study, we used a mixture of DNA barcoding, genital morphology and behavioral observations to determine the number of Epicephala moth species inhabiting the fruits of Breynia oblongifolia, their geographic distribution, pollinating behavior and phylogenetic relationships. RESULTS: We found that B. oblongifolia hosts two species of pollinator that co-occurred at all study sites, violating the assumption of reciprocal specificity. Male and female genital morphologies both differed considerably between the two moth species. In particular, females differed in the shape of their ovipositors, eggs and oviposition sites. Phylogenetic analyses indicated that the two Epicephala spp. on B. oblongifolia likely co-exist due to a host switch. In addition, we discovered that Breynia fruits are also often inhabited by a third moth, an undescribed species of Herpystis, which is a non-pollinating seed parasite. CONCLUSIONS: Our study reveals new complexity in interactions between Phyllantheae and Epicephala pollinators and highlights that host switching, co-speciation and non-pollinating seed parasites can shape species interactions in OPMs. Our finding that co-occurring Epicephala species have contrasting oviposition modes parallels other studies and suggests that such traits are important in Epicephala species coexistence.


Assuntos
Malpighiaceae/parasitologia , Parasitos/fisiologia , Polinização/fisiologia , Animais , Teorema de Bayes , Código de Barras de DNA Taxonômico , Feminino , Geografia , Masculino , Mariposas/anatomia & histologia , Mariposas/fisiologia , Mariposas/ultraestrutura , New South Wales , Ovário/citologia , Oviposição , Óvulo Vegetal/citologia , Parasitos/anatomia & histologia , Parasitos/ultraestrutura , Filogenia , Especificidade da Espécie
12.
J Urol ; 199(4): 1004-1010, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29108916

RESUMO

PURPOSE: Symptomatic urinary tract infection is a complication of office based cystourethroscopy. Studies are mixed regarding the efficacy of antibiotic prophylaxis to prevent urinary tract infections. Our aim was to develop and evaluate an evidence-based protocol that reduces unnecessary antibiotic use while avoiding an increase in urinary tract infections. MATERIALS AND METHODS: We created a clinic antibiogram based on all urology office visits performed during a 2-year period. Bacterial resistance rates, institutional risk related data and clinical guidelines were applied to create a protocol for antibiotic administration before cystourethroscopy. We then analyzed 1,245 consecutive patients without a renal transplant who underwent outpatient cystourethroscopy, including 610 after protocol initiation. Urinary tract infection rates and antibiotic use were analyzed for an association with the protocol change using the Fisher exact test. RESULTS: Cultures had an overall 20% rate of resistance to fluoroquinolones, representing 40% of the cultures that grew Escherichia coli. Before the protocol change 602 of 635 patients (94.8%) received a preprocedural antibiotic compared to 426 of 610 (69.9%) after protocol initiation (p <0.01). A total of 19 patients (3.0%) had a symptomatic urinary tract infection prior to the protocol change while 16 (2.6%) had a urinary tract infection after the change (p = 0.69). Regarding resistance, fluoroquinolone resistant organisms grew in the cultures of 12 of 19 patients (63.2%) with a urinary tract infection before the protocol change compared to 5 of 16 (31.3%) with a urinary tract infection after the change. Recent antibiotic administration, hospitalization and chronic catheterization were associated with urinary tract infection in the entire cohort (all p ≤0.01). CONCLUSIONS: A local antibiogram with infection related risk data effectively risk stratifies patients before cystourethroscopy, decreasing the use of antibiotics without increasing the rate of symptomatic urinary tract infection.


Assuntos
Antibioticoprofilaxia/métodos , Infecções Bacterianas/prevenção & controle , Protocolos Clínicos , Cistoscopia/efeitos adversos , Medicina Baseada em Evidências/métodos , Infecções Urinárias/prevenção & controle , Idoso , Antibacterianos/uso terapêutico , Antibioticoprofilaxia/normas , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Medicina Baseada em Evidências/normas , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Resultado do Tratamento , Infecções Urinárias/epidemiologia , Infecções Urinárias/microbiologia , Urologia/métodos , Urologia/normas
13.
Opt Express ; 26(6): 7313-7323, 2018 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-29609288

RESUMO

Mechanically robust and low loss single-mode arsenic sulfide fibers are used to deliver high power mid-infrared sources. Anti-reflection coatings were deposited on the fiber facets, enabling 90% transmission through 20 cm length fibers. 10.3 W was transmitted through an anti-reflection coated fiber at 2053 nm, and uncoated fibers sustained 12 MW/cm2 intensities on the facet without failure. A Cr:ZnSe laser transmitted >1 W at 2520 nm, and a Fe:ZnSe laser transmitted 0.5 W at 4102 nm. These results indicate that by improving the anti-reflection coatings and using a high beam quality mid-infrared source, chalcogenide fibers can reliably deliver ≥10 W in a single mode, potentially out to 6.5 µm.

14.
Scand J Med Sci Sports ; 28(11): 2369-2374, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29862593

RESUMO

Patellar tendon pathology appears to develop in young athletes. It is not known how this tendon develops through adolescence. This longitudinal study investigated proximal patellar tendon development during the adolescent growth spurt in young ballet dancers and identified whether puberty (estimated by maturity offset) had an effect on tendon development. Fifty two dancers (32 female and 20 male dancers, ages 11-18 at baseline) had ultrasound images of their tendons every 6 months for 2 years. Changes in tendon size (anterior-posterior diameter) on grayscale images and echogenicity, as quantified using ultrasound tissue characterization, were recorded each time. Maturity offset was calculated used to estimate peak height velocity (adolescent growth spurt). Maturity offset did not affect effect tendon composition before peak height velocity; however, after participants passed peak height velocity, maturity offset increased the composition of stable echopattern (P < .05): a 4% differential increase in type I echopattern, indicative of normal tendon structure, and a decrease in type III echopattern (more disorganized echopattern) by 0.7% per year. Anterior-posterior thickness increased by 0.2 mm/y (P < .05) measured 2 cm below the patella. Following peak height velocity, the proximal patellar tendon attachment increased in thickness and demonstrated a more stable echopattern representative of aligned fibrillar structure. Future research is required to further understand this normal maturation and the factors that support this process, with the aim of reducing the development of patellar tendon pathology in the adolescent jumping athlete.


Assuntos
Dança , Ligamento Patelar/anatomia & histologia , Ligamento Patelar/diagnóstico por imagem , Adolescente , Antropometria , Atletas , Criança , Feminino , Humanos , Estudos Longitudinais , Masculino , Ultrassonografia
15.
Scand J Med Sci Sports ; 28(9): 2035-2041, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29658150

RESUMO

Patellar tendinopathy (tendon pain and dysfunction), or jumper's knee, is prevalent in adult jumping athletes. Pathology in the proximal patellar tendon is a key risk factor for developing patellar tendinopathy. When pathology develops in the proximal patellar tendon is not known, although it is reported to exist in adolescent athletes. The aim of this study was to follow young jumping athletes (ballet dancers) through adolescence to identify whether pathology develops and its relation to the adolescent growth spurt. Fifty-seven elite ballet students between ages 11 and 18 were monitored for 2 years. Data were collected every 6 months, including an ultrasound scan on their left tendons using ultrasound tissue characterization (UTC) to quantify intratendinous changes, anthropometric data to calculate peak height velocity (adolescent growth spurt), participant reports of any injuries or dance modifications, and a VISA-P and single leg decline squat for patellar tendon pain. Nine percentage of adolescent dancers developed pathology during this study, and development was not associated with growth spurt. Peak height velocity and dance participation/volume both at the start and throughout the study were similar in those who did develop pathology and those who did not. Only 2 of 5 participants who developed pathology reported pain associated with their tendon. Pathology in the proximal patellar tendon can develop during adolescence.


Assuntos
Dança , Ligamento Patelar/patologia , Tendinopatia/epidemiologia , Adolescente , Atletas , Criança , Feminino , Humanos , Estudos Longitudinais , Masculino , Medição da Dor , Ligamento Patelar/diagnóstico por imagem , Ultrassonografia
16.
Scand J Med Sci Sports ; 28(9): 2016-2022, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29572969

RESUMO

Little is known about the prevalence and associated of morbidity of tendon problems. With only severe cases of tendon problems missing games, players that have their training and performance impacted are not captured by traditional injury surveillance. The aim of this study was to report the prevalence of Achilles and patellar tendon problems in elite male Australian football players using the Oslo Sports Trauma Research Centre (OSTRC) overuse questionnaire, compared to a time-loss definition. Male athletes from 12 professional Australian football teams were invited to complete a monthly questionnaire over a 9-month period in the 2016 pre- and competitive season. The OSTRC overuse injury questionnaire was used to measure the prevalence and severity of Achilles and patellar tendon symptoms and was compared to traditional match-loss statistics. A total of 441 participants were included. Of all participants, 21.5% (95% CI: 17.9-25.6) and 25.2% (95% CI 21.3-29.4) reported Achilles or patellar tendon problems during the season, respectively. Based on the traditional match-loss definition, a combined 4.1% of participants missed games due to either Achilles or patellar tendon injury. A greater average monthly prevalence was observed during the pre-season compared to the competitive season. Achilles and patellar tendon problems are prevalent in elite male Australian football players. These injuries are not adequately captured using a traditional match-loss definition. Prevention of these injuries may be best targeted during the off- and pre-season due to higher prevalence of symptoms during the pre-season compared to during the competitive season.


Assuntos
Traumatismos em Atletas/epidemiologia , Futebol/lesões , Traumatismos dos Tendões/epidemiologia , Tendão do Calcâneo/lesões , Adolescente , Atletas , Austrália , Humanos , Masculino , Ligamento Patelar/lesões , Prevalência , Adulto Jovem
17.
Osteoarthritis Cartilage ; 25(3): 364-368, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27480934

RESUMO

OBJECTIVE: To describe, explain and give practical suggestions regarding important principles and key methodological challenges in the study design, statistical analysis, and reporting of results from in vivo studies. CONCLUSIONS: Pre-specifying endpoints and analysis, recognizing the common underlying assumption of statistically independent observations, performing sample size calculations, and addressing multiplicity issues are important parts of an in vivo study. A clear reporting of results and informative graphical presentations of data are other important parts.


Assuntos
Pesquisa Biomédica/métodos , Osteoartrite/terapia , Projetos de Pesquisa , Animais , Pesquisa Biomédica/normas , Protocolos Clínicos/normas , Interpretação Estatística de Dados , Humanos , Publicações/normas , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Tamanho da Amostra
18.
Mol Ecol ; 26(3): 937-950, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28026893

RESUMO

A key debate in ecology centres on the relative importance of niche and neutral processes in determining patterns of community assembly with particular focus on whether ecologically similar species with similar functional traits are able to coexist. Meanwhile, molecular studies are increasingly revealing morphologically indistinguishable cryptic species with presumably similar ecological roles. Determining the geographic distribution of such cryptic species provides opportunities to contrast predictions of niche vs. neutral models. Discovery of sympatric cryptic species increases alpha diversity and supports neutral models, while documentation of allopatric/parapatric cryptic species increases beta diversity and supports niche models. We tested these predictions using morphological and molecular data, coupled with environmental niche modelling analyses, of a fig wasp community along its 2700-km latitudinal range. Molecular methods increased previous species diversity estimates from eight to eleven species, revealing morphologically cryptic species in each of the four wasp genera studied. Congeneric species pairs that were differentiated by a key morphological functional trait (ovipositor length) coexisted sympatrically over large areas. In contrast, morphologically similar species, with similar ovipositor lengths, typically showed parapatric ranges with very little overlap. Despite parapatric ranges, environmental niche models of cryptic congeneric pairs indicate large regions of potential sympatry, suggesting that competitive processes are important in determining the distributions of ecologically similar species. Niche processes appear to structure this insect community, and cryptic diversity may typically contribute mostly to beta rather than alpha diversity.


Assuntos
Ecossistema , Simpatria , Vespas/classificação , Animais , Ficus
19.
Br J Surg ; 104(12): 1634-1639, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29044488

RESUMO

BACKGROUND: Nail-bed injuries are the most common hand injury in children. Surgical dogma is to replace the nail plate after repairing the nail bed. Recent evidence suggests this might increase infection rates and returns to clinic. The aim of this feasibility trial was to inform the design and conduct of a definitive trial comparing replacing or discarding the nail plate after nail-bed repair. METHODS: This study recruited participants from four hand units in the UK between April and July 2015. Participants were children under the age of 16 years with a nail-bed injury requiring surgery. They were randomized to either having the nail plate replaced or discarded after nail-bed repair. The follow-up method was also allocated randomly (postal versus clinic). Information was collected on complications at 2 weeks and 30 days, and on nail-plate appearance at 4 months using the Zook classification. Two possible approaches to follow-up were also piloted and compared. RESULTS: During the recruitment phase, there were 156 potentially eligible children. Sixty were randomized in just over 3 months using remote web-based allocation. By 2 weeks, there were two infections, both in children with replaced nail plates. The nail-replaced group also experienced more complications. There was no evidence of a difference in return rates between postal and clinic follow-up. CONCLUSION: Recruitment was rapid and nail-bed repair appeared to have low complication and infection rates in this pilot trial. The findings have led to revision of the definitive trial protocol, including the mode and timing of follow-up, and modification of the Zook classification.


Assuntos
Unhas/lesões , Unhas/cirurgia , Procedimentos de Cirurgia Plástica , Adolescente , Antibacterianos/uso terapêutico , Criança , Pré-Escolar , Estudos de Viabilidade , Feminino , Humanos , Lactente , Masculino , Dor/etiologia , Projetos Piloto , Complicações Pós-Operatórias , Estudos Prospectivos , Procedimentos de Cirurgia Plástica/efeitos adversos , Infecção da Ferida Cirúrgica/tratamento farmacológico
20.
Phys Rev Lett ; 118(18): 185001, 2017 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-28524672

RESUMO

A fast Alfvén wave with a finite amplitude is shown to grow by a stimulated emission process that we propose for exploitation in toroidal magnetically confined fusion plasmas. Stimulated emission occurs while the wave propagates inward through the outer midplane plasma, where a population inversion of the energy distribution of fusion-born ions is observed to arise naturally. Fully nonlinear first-principles simulations, which self-consistently evolve particles and fields under the Maxwell-Lorentz system, demonstrate this novel "α-particle channeling" scenario for the first time.

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