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1.
Opt Lett ; 47(17): 4323-4326, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36048644

RESUMO

An interleaved, chirped electro-optic dual comb system is demonstrated for rapid, high dynamic range measurements of cavity optomechanical sensors. This approach allows for the cavity displacements to be interrogated at measurement times as fast as 10 µs over ranges far larger than can be achieved with alternative methods. While the performance of this novel, to the best of our knowledge, readout approach is evaluated with an optomechanical accelerometer, this method has a wide range of applications including temperature, pressure, and humidity sensing as well as acoustics and molecular spectroscopy.

2.
Stat Med ; 35(27): 4980-4993, 2016 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-27439856

RESUMO

Diagnostic evaluation of suspected breast cancer due to abnormal screening mammography results is common, creates anxiety for women and is costly for the healthcare system. Timely evaluation with minimal use of additional diagnostic testing is key to minimizing anxiety and cost. In this paper, we propose a Bayesian semi-Markov model that allows for flexible, semi-parametric specification of the sojourn time distributions and apply our model to an investigation of the process of diagnostic evaluation with mammography, ultrasound and biopsy following an abnormal screening mammogram. We also investigate risk factors associated with the sojourn time between diagnostic tests. By utilizing semi-Markov processes, we expand on prior work that described the timing of the first test received by providing additional information such as the mean time to resolution and proportion of women with unresolved mammograms after 90 days for women requiring different sequences of tests in order to reach a definitive diagnosis. Overall, we found that older women were more likely to have unresolved positive mammograms after 90 days. Differences in the timing of imaging evaluation and biopsy were generally on the order of days and thus did not represent clinically important differences in diagnostic delay. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Diagnóstico Tardio , Cadeias de Markov , Teorema de Bayes , Detecção Precoce de Câncer , Feminino , Humanos , Mamografia , Programas de Rastreamento
3.
Trends Ecol Evol ; 39(7): 677-688, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38508922

RESUMO

Although primarily studied through the lens of community ecology, phenomena consistent with priority effects appear to be widespread across many different scenarios spanning a broad range of spatial, temporal, and biological scales. However, communication between these research fields is inconsistent and has resulted in a fragmented co-citation landscape, likely due to the diversity of terms used to refer to priority effects across these fields. We review these related terms, and the biological contexts in which they are used, to facilitate greater cross-disciplinary cohesion in research on priority effects. In breaking down these semantic barriers, we aim to provide a framework to better understand the conditions and mechanisms of priority effects, and their consequences across spatial and temporal scales.


Assuntos
Ecologia , Ecologia/métodos , Biologia
4.
Epidemiol Infect ; 140(5): 798-802, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21878146

RESUMO

The spring of 2009 witnessed the emergence of a novel influenza A(H1N1) virus resulting in the first influenza pandemic since 1968. In autumn of 2010, the 2009 novel H1N1 influenza strain re-emerged. We performed a retrospective time-series analysis of all patients with laboratory-confirmed H1N1 influenza who presented to our institution during 2009. Cases of influenza were assembled into 3-day aggregates and forecasting models of H1N1 influenza incidence were created. Forecasting estimates of H1N1 incidence for the 2010-2011 season were compared to actual values for our institution to assess model performance. Ninety-five percent confidence intervals calculated around our model's forecasts were accurate to ±3·6 cases per 3-day period for our institution. Our results suggest that time-series models may be useful tools in forecasting the incidence of H1N1 influenza, helping institutions to optimize distribution of resources based on the changing burden of illness.


Assuntos
Hospitalização/estatística & dados numéricos , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H1N1/patogenicidade , Influenza Humana/epidemiologia , Influenza Humana/virologia , Criança , Pré-Escolar , Estudos de Coortes , Humanos , Incidência , Estudos Retrospectivos , Fatores de Tempo
5.
Food Chem ; 126(4): 1771-8, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25213956

RESUMO

The retention and speciation of selenium in flour and bread was determined following experimental applications of selenium fertilisers to a high-yielding UK wheat crop. Flour and bread were produced using standard commercial practices. Total selenium was measured using inductively coupled plasma-mass spectrometry (ICP-MS) and the profile of selenium species in the flour and bread were determined using high performance liquid chromatography (HPLC) ICP-MS. The selenium concentration of flour ranged from 30ng/g in white flour and 35ng/g in wholemeal flour from untreated plots up to >1800ng/g in white and >2200ng/g in wholemeal flour processed from grain treated with selenium (as selenate) at the highest application rate of 100g/ha. The relationship between the amount of selenium applied to the crop and the amount of selenium in flour and bread was approximately linear, indicating minimal loss of Se during grain processing and bread production. On average, application of selenium at 10g/ha increased total selenium in white and wholemeal bread by 155 and 185ng/g, respectively, equivalent to 6.4 and 7.1µg selenium per average slice of white and wholemeal bread, respectively. Selenomethionine accounted for 65-87% of total extractable selenium species in Se-enriched flour and bread; selenocysteine, Se-methylselenocysteine selenite and selenate were also detected. Controlled agronomic biofortification of wheat crops for flour and bread production could provide an appropriate strategy to increase the intake of bioavailable selenium.

6.
Med Hypotheses ; 122: 165-171, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30593404

RESUMO

Intracellular ferritin is known to store iron, an essential element in an array of physiological processes. But what purpose does serum ferritin serve, what controls ultra-high hyperferritinaemia (ferritin levels above 4000 ng/ml), and finally why is it raised in inflammatory diseases, the most impressive being haemophagocytic lymphohistiocytosis? This paper proposes a hypothesis and model to explain the above questions. Serum ferritin has some unfamiliar physiological properties. It dampens severe inflammation by inhibiting lymphocyte activity, hinders bacterial growth by acting as an iron chelator and slows malignant growth by having an antiangiogenic effect. Therefore, serum ferritin is effective at modulating many conditions and could be a desired physiological process in malignancy or infection. The proposed theory is that phagocytic cells fuse with pathological native cells in much the same way as macrophages do when forming multinucleated giant cells. The pathological cells can be "infected" by intracellular pathogens or the malignant phenotype. These fusion cells result in a massive upregulation of exclusive features of macrophage activity such as phagocytosis, iron metabolism and ferritin release. Dysfunctional mitochondria are critical to this process, Pathological cells that contain dysfunctional mitochondria "infect" phagocytic mitochondrial following cellular fusion, resulting in ferritin release. The key evidence suporting this idea: macrophages are the source of ferritin secretion; they have intimate contact with known triggers of HLH, allowing for fusion hybrids, and they commonly fuse with cells. It is also argued that exclusively intracellular pathologies trigger HLH, which is a requirement for this model. HLH has features of a mitochondriopathy and finally it is debated that all the defective genes known to trigger familial-HLH can increase the likelihood of macrophage fusion. If this hypothesis is correct, the implications might discover novel diagnostic tools to detect HLH and point to avenues of targeted therapy. This is a bold theory with interesting perspectives on cell biology and clinical medicine. The paper discusses the evidence and challenges of this proposed mechanism in describing hyperferritinaemia and its relation to HLH.


Assuntos
Sobrecarga de Ferro/complicações , Sobrecarga de Ferro/fisiopatologia , Linfo-Histiocitose Hemofagocítica/complicações , Linfo-Histiocitose Hemofagocítica/fisiopatologia , Animais , Ferritinas/metabolismo , Humanos , Inflamação , Macrófagos/metabolismo , Modelos Teóricos , Metástase Neoplásica , Fagocitose , Fenótipo
7.
Ecology ; 100(8): e02727, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30985910

RESUMO

Character displacement may facilitate species coexistence through niche partitioning. However, the degree to which character displacement influences broader patterns of community assembly is unclear. Here, we capitalize on a natural experiment of community assembly on the oceanic island of Bermuda. Over the past century, three species of ecologically similar but distantly related Anolis lizards have been introduced to Bermuda where no Anolis has ever naturally existed. The Jamaican anole (A. grahami) arrived first in 1905 and dispersed rapidly across the island. Five decades later, the Antiguan anole (A. leachii) and the Barbadian anole (A. extremus) were introduced to independent locations. In 1991, A. leachii and A. extremus were observed to nearly meet at a contact zone, but not yet to coexist. We record that subsequent range expansion at this contact zone has been asymmetrical; A. leachii invaded the range of A. extremus, but reciprocal invasion by A. extremus has not occurred. When in allopatry in Bermuda, both species occupy identical ecological space. However, A. leachii underwent rapid ecological character displacement to use arboreal habitat when invading the range of A. extremus. These findings highlight how character displacement may influence the process of dispersal and drive patterns of coexistence and community assembly.


Assuntos
Lagartos , Animais , Bermudas , Ecologia , Ecossistema
8.
Sci Rep ; 8(1): 7568, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29765102

RESUMO

Acute nicotine abstinence in cigarette smokers results in deficits in performance on specific cognitive processes, including working memory and impulsivity which are important in relapse. Cannabidiol (CBD), the non-intoxicating cannabinoid found in cannabis, has shown pro-cognitive effects and preliminary evidence has indicated it can reduce the number of cigarettes smoked in dependent smokers. However, the effects of CBD on cognition have never been tested during acute nicotine withdrawal. The present study therefore aimed to investigate if CBD can improve memory and reduce impulsivity during acute tobacco abstinence. Thirty, non-treatment seeking, dependent, cigarette smokers attended two laboratory-based sessions after overnight abstinence, in which they received either 800 mg oral CBD or placebo (PBO), in a randomised order. Abstinence was biologically verified. Participants were assessed on go/no-go, delay discounting, prose recall and N-back (0-back, 1-back, 2-back) tasks. The effects of CBD on delay discounting, prose recall and the N-back (correct responses, maintenance or manipulation) were null, confirmed by a Bayesian analysis, which found evidence for the null hypothesis. Contrary to our predictions, CBD increased commission errors on the go/no-go task. In conclusion, a single 800 mg dose of CBD does not improve verbal or spatial working memory, or impulsivity during tobacco abstinence.


Assuntos
Canabidiol/administração & dosagem , Comportamento Impulsivo/efeitos dos fármacos , Memória/efeitos dos fármacos , Tabagismo/psicologia , Adulto , Teorema de Bayes , Canabidiol/farmacologia , Feminino , Humanos , Masculino , Memória de Curto Prazo/efeitos dos fármacos , Distribuição Aleatória , Memória Espacial/efeitos dos fármacos , Adulto Jovem
9.
Psychopharmacology (Berl) ; 235(2): 459-466, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29085980

RESUMO

RATIONALE: Depressed patients robustly exhibit affective biases in emotional processing which are altered by SSRIs and predict clinical outcome. OBJECTIVES: The objective of this study is to investigate whether psilocybin, recently shown to rapidly improve mood in treatment-resistant depression (TRD), alters patients' emotional processing biases. METHODS: Seventeen patients with treatment-resistant depression completed a dynamic emotional face recognition task at baseline and 1 month later after two doses of psilocybin with psychological support. Sixteen controls completed the emotional recognition task over the same time frame but did not receive psilocybin. RESULTS: We found evidence for a group × time interaction on speed of emotion recognition (p = .035). At baseline, patients were slower at recognising facial emotions compared with controls (p < .001). After psilocybin, this difference was remediated (p = .208). Emotion recognition was faster at follow-up compared with baseline in patients (p = .004, d = .876) but not controls (p = .263, d = .302). In patients, this change was significantly correlated with a reduction in anhedonia over the same time period (r = .640, p = .010). CONCLUSIONS: Psilocybin with psychological support appears to improve processing of emotional faces in treatment-resistant depression, and this correlates with reduced anhedonia. Placebo-controlled studies are warranted to follow up these preliminary findings.


Assuntos
Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Emoções/efeitos dos fármacos , Reconhecimento Facial/efeitos dos fármacos , Alucinógenos/uso terapêutico , Psilocibina/uso terapêutico , Sistemas de Apoio Psicossocial , Adulto , Transtorno Depressivo Resistente a Tratamento/psicologia , Emoções/fisiologia , Expressão Facial , Reconhecimento Facial/fisiologia , Feminino , Seguimentos , Alucinógenos/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Psilocibina/farmacologia , Resultado do Tratamento , Adulto Jovem
10.
J Dairy Sci ; 90(11): 5276-81, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17954768

RESUMO

Sixty Holstein calves (30 bulls, 30 heifers) were used to examine the effects of supplemental lactoferrin on feed intake, growth, and health during the preweaning and postweaning periods. One of 3 levels of lactoferrin was supplemented from 3 to 56 d in either whole milk or water to produce 3 dietary treatments: 1) 0 g/d, 2) 0.5 g/d, and 3) 1 g/d. Whole milk (3.8 L/d) containing lactoferrin supplements was fed from bottles until weaning at 35 d. From d 36 to 56, lactoferrin supplements were added to water (15 to 25 mL) and fed from bottles. Lactoferrin supplementation had no effect on feed intake, body weight, average daily gain, heart girth, body temperature, fecal scores, respiratory scores, or haptoglobin concentrations. Calves were housed in individual pens in either an open-sided barn or hutches. Calves raised in the barn consumed more calf starter and therefore grew better than calves raised in hutches. Under the conditions of this study, lactoferrin supplementation was not beneficial. Further research is needed to fully elucidate the role of lactoferrin, and possible benefits during different feeding conditions or milk sources.


Assuntos
Peso Corporal/efeitos dos fármacos , Bovinos/fisiologia , Suplementos Nutricionais , Ingestão de Alimentos/efeitos dos fármacos , Lactoferrina/farmacologia , Ração Animal/análise , Animais , Constituição Corporal/efeitos dos fármacos , Temperatura Corporal/efeitos dos fármacos , Bovinos/crescimento & desenvolvimento , Bovinos/imunologia , Bovinos/metabolismo , Dieta/veterinária , Feminino , Haptoglobinas/metabolismo , Nível de Saúde , Abrigo para Animais , Imunização Passiva/veterinária , Lactoferrina/administração & dosagem , Análise dos Mínimos Quadrados , Masculino , Respiração/efeitos dos fármacos , Desmame
11.
Dev Comp Immunol ; 6(3): 557-67, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6982182

RESUMO

Pooled normal bat serum was separated by gel filtration to give fractions rich in IgG-, Iga- and IgM-like proteins. These fractions were analogous to the corresponding human immunoglobulin classes by immunoelectrophoresis and SDS-polyacrylamide gel electrophoresis. Rabbits were immunized with the fractions and the antisera absorbed. Neotropical bats (Artibeus lituratus) were infected with Histoplasma capsulatum and serum samples were collected weekly and tested for specific serologic response to the fungus. A radial immunodiffusion test was devised to monitor changes in concentrations of IgG, IgA and IgM in the same sera. Bats infected with a low dose of fungus had significantly increased levels of IgM and IgA between 2-6 weeks post-infection. Bats receiving a high dose maintained elevated levels of IgM and IgA through the end of the study. Significantly elevated levels of IgG were not detected until late in the disease (8-9 weeks). In bats with histoplasmosis, IgM and IgA appeared to contribute primarily to the early positive serologies, while precipitating antibodies of the IgG class were detectable later in the disease. These results are similar to the serologic profile seen in human histoplasmosis, and extend our understanding of comparative immune responses in an important wildlife reservoir of human mycotic pathogens.


Assuntos
Quirópteros/imunologia , Histoplasmose/imunologia , Imunoglobulinas/isolamento & purificação , Animais , Especificidade de Anticorpos , Antígenos Heterófilos/imunologia , Feminino , Histoplasmose/transmissão , Humanos , Imunoeletroforese , Imunoglobulina A/isolamento & purificação , Imunoglobulina G/biossíntese , Imunoglobulina G/isolamento & purificação , Imunoglobulina M/biossíntese , Imunoglobulina M/isolamento & purificação , Imunoglobulinas/imunologia , Masculino , Peso Molecular , Coelhos
12.
Arch Dermatol ; 120(2): 243-4, 1984 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6696480

RESUMO

Congenital onychodysplasia of the index fingers (Iso and Kikuchi syndrome) is characterized by five criteria: (1) congenital occurrence, (2) unilateral or bilateral index finger involvement, (3) variability in nail appearance, (4) possible hereditary involvement, and (5) frequently associated bone anomalies. Emphasis is placed on the configuration of the lunula, which is deformed and plays an important role in shaping the free edge of the nail plate. To our knowledge, this deformity has not been previously described in this syndrome.


Assuntos
Unhas Malformadas , Adulto , Humanos , Masculino , Síndrome
13.
J Biomech ; 33(4): 443-55, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10768393

RESUMO

Flow patterns and flow-related stresses contribute to the characterization of health risks, particularly the risk of plaque rupture, posed by a particular atherosclerotic stenosis. Blood flow in the presence of significant plaque deposits is investigated, and the influence of factors such as stenosis morphology and surface irregularity is evaluated. Solutions for three-dimensional, unsteady flow in these stenotic vessels are obtained for an incompressible, Newtonian fluid. The equations of motion are solved numerically using a finite volume formulation. The resulting flow patterns and shear and normal stresses are interpreted with respect to diagnostic implications, including the possibility of plaque rupture. The inadequacy of "percent stenosis" to characterize the risks posed by a particular plaque is demonstrated. Surface irregularity, stenosis aspect ratio, and the shape of the pulsatile waveform all have considerable influence on the flow field and on the stresses on the plaque. A measure of surface irregularity or plaque symmetry, in particular, may complement percent stenosis in diagnosing the risk of plaque rupture.


Assuntos
Arteriosclerose/patologia , Arteriosclerose/fisiopatologia , Vasos Sanguíneos/fisiopatologia , Modelos Cardiovasculares , Humanos , Fluxo Sanguíneo Regional/fisiologia
14.
Dermatol Clin ; 5(3): 581-94, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3301115

RESUMO

Variations in the structure of the hair shaft are commonly seen under the microscope and are usually of little clinical significance. Defects of the hair shaft become significant when they produce an unsightly cosmetic appearance or when they lead to the diagnosis of an underlying metabolic disorder or genetic syndrome. The article reviews hair-shaft anomalies and presents updated information and relevant clinical guidelines for diagnosing such defects.


Assuntos
Doenças do Cabelo/etiologia , Cabelo/patologia , Humanos
15.
Cutis ; 40(3): 272-6, 1987 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3652735

RESUMO

Telogen effluvium, alopecia areata, traction/chemical alopecia, and androgenetic alopecia account for more than 90 percent of all causes of hair loss in patients presenting to the dermatologist's office. A thorough understanding of these hair diseases will enable the practicing dermatologist to effectively manage the vast majority of patients who present with scalp hair loss.


Assuntos
Doenças do Cabelo/diagnóstico , Alopecia/diagnóstico , Alopecia/etiologia , Alopecia/terapia , Alopecia em Áreas/diagnóstico , Alopecia em Áreas/etiologia , Alopecia em Áreas/terapia , Feminino , Doenças do Cabelo/etiologia , Doenças do Cabelo/terapia , Humanos
16.
Angle Orthod ; 68(2): 141-6, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9564423

RESUMO

This study describes mesial and distal enamel thickness of the permanent posterior mandibular dentition. The sample comprised 98 Caucasian adults (59 males, 39 females) 20 to 35 years old. Bitewing radiographs of the right permanent mandibular premolars and first and second molars were illuminated and transferred to a computer at a fixed magnification via a video camera. Enamel and dentin thicknesses were identified and digitized on the plane representing the maximum mesiodistal diameter of each tooth. The results showed that there were no significant sex differences in either mesial or distal enamel thickness. Enamel on the second molars was significantly thicker (0.3 to 0.4 mm) than enamel on the premolars. Distal enamel was significantly thicker than mesial enamel. There was approximately 10 mm of total enamel on the four teeth combined. Assuming 50% enamel reduction, the premolars and molars should provide 9.8 mm of additional space for realignment of mandibular teeth.


Assuntos
Dente Pré-Molar/anatomia & histologia , Esmalte Dentário/anatomia & histologia , Má Oclusão/terapia , Dente Molar/anatomia & histologia , Adolescente , Adulto , Dente Pré-Molar/diagnóstico por imagem , Esmalte Dentário/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Mandíbula , Dente Molar/diagnóstico por imagem , Ajuste Oclusal , Intensificação de Imagem Radiográfica , Radiografia Interproximal , Extração Seriada , Fatores Sexuais
17.
Environ Pollut ; 158(10): 3085-94, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20656390

RESUMO

Four plant species (oilseed rape, Brassica napus L.; red clover, Trifolium pratense L.; ryegrass, Lolium perenne L.; and tomato, Lycopersicon esculentum L.) were tested on ten soils varying widely in soil properties to assess molybdenum (Mo) toxicity. A larger range (66-fold-609-fold) of added Mo concentrations resulting in 50% inhibition of yield (ED50) was found among soils than among plant species (2-fold-38-fold), which illustrated that the soils differed widely in the expression of Mo toxicity. Toxicity thresholds based on soil solution Mo narrowed the variation among soils compared to thresholds based on added Mo concentrations. We conclude that plant bioavailability of Mo in soil depends on Mo solubility, but this alone did not decrease the variability in observed toxicity enough to be used in risk assessment and that other soil properties influencing Mo toxicity to plants need to be considered.


Assuntos
Molibdênio/toxicidade , Plantas/efeitos dos fármacos , Poluentes do Solo/toxicidade , Brassica napus/efeitos dos fármacos , Relação Dose-Resposta a Droga , Previsões , Lolium/efeitos dos fármacos , Solanum lycopersicum/efeitos dos fármacos , Medição de Risco , Trifolium/efeitos dos fármacos
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