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1.
Ir Med J ; 115(4): 584, 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35695798

RESUMO

Aim The fundamental concept of multidisciplinary education is a shared mental model that leads to better interdependent collaboration. The aim of this bootcamp was to create a sustainable induction curriculum for Anaesthesiology and Emergency Medicine trainees and nurses through training in a simulated multidisciplinary environment. Methods The two-day bootcamp consisted of lectures, equipment demonstration, workshops, and high-fidelity simulated scenarios. A pre- and post-course MCQ test was used for assessment of knowledge acquisition. Pre and post confidence scores were used to evaluate procedural skill confidence level. A 5-point Likert scale was used to evaluate qualitative feedback from participants. Results Seven anaesthesiology trainees, two anaesthetic nurses, six emergency medicine trainees and three emergency medicine nurses were enrolled. There was a statistically significant increase (p-value<0.01) in post-MCQ scores, portraying significant knowledge acquisition. The total procedural confidence scores increased from 375 (±9.15) to 550 (±8.43), (p < 0.01). All participants agreed that the stated educational objectives were met and relevant to their clinical practice, and strongly commended team training exercises. Conclusion Multidisciplinary simulation-based training improves team performance as well as transfer of knowledge across two or more disciplines. Overlapped training between Anaesthesiology and Emergency Medicine created an opportunity for sharing of educational resources in the current time-based speciality training system.


Assuntos
Anestesiologia , Medicina de Emergência , Treinamento por Simulação , Competência Clínica , Currículo , Humanos
2.
Am J Phys Anthropol ; 175(1): 282-291, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33386624

RESUMO

OBJECTIVE: We describe a new method for identifying and quantifying the magnitude and rate of short-term weight faltering episodes, and assess how (a) these episodes relate to broader growth outcomes, and (b) different data collection intervals influence the quantification of weight faltering. MATERIALS AND METHODS: We apply this method to longitudinal growth data collected every other day across the first year of life in Gambian infants (n = 124, males = 65, females = 59). Weight faltering episodes are identified from velocity peaks and troughs. Rate of weight loss and regain, maximum weight loss, and duration of each episode were calculated. We systematically reduced our dataset to mimic various potential measurement intervals, to assess how these intervals affect the ability to derive information about short-term weight faltering episodes. We fit linear models to test whether metrics associated with growth faltering were associated with growth outcomes at 1 year, and generalized additive mixed models to determine whether different collection intervals influence episode identification and metrics. RESULTS: Three hundred weight faltering episodes from 119 individuals were identified. The number and magnitude of episodes negatively impacted growth outcomes at 1 year. As data collection interval increases, weight faltering episodes are missed and the duration of episodes is overestimated, resulting in the rate of weight loss and regain being underestimated. CONCLUSIONS: This method identifies and quantifies short-term weight faltering episodes, that are in turn negatively associated with growth outcomes. This approach offers a tool for investigators interested in understanding how short-term weight faltering relates to longer-term outcomes.


Assuntos
Peso Corporal/fisiologia , Desenvolvimento Infantil/fisiologia , Insuficiência de Crescimento/fisiopatologia , Antropologia Física , Gâmbia , Transtornos do Crescimento , Humanos , Lactente , Recém-Nascido , Modelos Estatísticos , Estudos Retrospectivos , Síndrome de Emaciação
3.
Emerg Radiol ; 27(3): 293-301, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32095905

RESUMO

PURPOSE: To qualitatively assess the legibility of radiopaque patient identification stickers and their effect on image quality. These stickers are intended for use as a part of a patient registration and identification pack utilized in a mass casualty incident (MCI), to prevent errors in correlating patients with their diagnostic imaging and reports. METHODS: Four different prototype designs of stickers with radiopaque identification numbers which are legible on radiographs and CT were created. These were affixed to head and thorax phantoms and scanned using standard imaging protocols. Images were reviewed qualitatively for legibility and the presence of image degradation due to the radiopaque sticker materials using Likert scales by four radiologists and four emergency physicians. RESULTS: All four prototypes were confidently legible on forehead, shoulder and sternum on CT on topogram and reconstructed images. Sticker positioning over the temple resulted in unreliable legibility on topogram. All prototypes were confidently legible on shoulder and sternum on CT and radiographs. Significant image degradation was reported on radiographs with sticker position over the sternum. The preferred anatomic position was the forehead. CONCLUSION: In a mass casualty incident, radiopaque patient identification stickers affixed to injured patients may help to ensure confidence in the correlation between patients and their imaging. Tested prototypes were found to be easily legible without substantial degradation of image quality. Preferred anatomical position and construction material was established. Consideration should be given to addition of such radiographic identity aides to MCI patient registration packs.


Assuntos
Incidentes com Feridos em Massa , Sistemas de Identificação de Pacientes , Tomografia Computadorizada por Raios X , Artefatos , Desenho de Equipamento , Testa , Humanos , Imagens de Fantasmas , Ombro , Esterno
4.
Appl Opt ; 57(24): 6966-6970, 2018 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-30129585

RESUMO

Laser beam shaping can play a crucial role in improving many laser processes, especially in selective laser patterning of thin films for display devices and solar cells. Typical Gaussian spatial energy distributions can increase damage to the substrate and lead to large crater edge ridges, which are sub-optimal for typical industrial thin film processes. We report on the design, fabrication, and testing of reflective silicon diffractive optics developed for spatial beam shaping at a wavelength of 355 nm. The application of the elements for laser-selective removal of 20 nm indium tin oxide thin films on glass substrates is demonstrated. The design of the phase profile is first generated using the numerical method of computer-generated holography. The phase profiles are realized on a silicon substrate using a novel two-step fabrication technique consisting of a calibrated focused ion beam and an inductively coupled plasma etch. This results in truly grey-scale, blazed diffractive optics, which were analyzed using white light interferometry and atomic force microscopy. Using the diffractive elements with 355 nm nanosecond pulses shows excellent focused spot profiles with a good reproduction of the intended design with a first-order off-axis diffractive efficiency of approximately 80% at a 45 deg angle of incidence.

5.
Clin Exp Immunol ; 183(3): 419-30, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26439909

RESUMO

Killer immunoglobulin-like receptors (KIRs) interact with human leucocyte antigen (HLA) class I ligands and play a key role in the regulation and activation of NK cells. The functional importance of KIR-HLA interactions has been demonstrated for a number of chronic viral infections, but to date only a few studies have been performed in the context of acute self-limited viral infections. During our investigation of CD8(+) T cell responses to a conserved HLA-B57-restricted epitope derived from dengue virus (DENV) non-structural protein-1 (NS1), we observed substantial binding of the tetrameric complex to non-T/non-B lymphocytes in peripheral blood mononuclear cells (PBMC) from a long-standing clinical cohort in Thailand. We confirmed binding of the NS1 tetramer to CD56(dim) NK cells, which are known to express KIRs. Using depletion studies and KIR-transfected cell lines, we demonstrated further that the NS1 tetramer bound the inhibitory receptor KIR3DL1. Phenotypical analysis of PBMC from HLA-B57(+) subjects with acute DENV infection revealed marked activation of NS1 tetramer-binding natural killer (NK) cells around the time of defervescence in subjects with severe dengue disease. Collectively, our findings indicate that subsets of NK cells are activated relatively late in the course of acute DENV illness and reveal a possible role for specific KIR-HLA interactions in the modulation of disease outcomes.


Assuntos
Vírus da Dengue/química , Dengue/imunologia , Células Matadoras Naturais/imunologia , Fragmentos de Peptídeos/imunologia , Receptores KIR3DL1/imunologia , Receptores KIR3DL1/metabolismo , Proteínas não Estruturais Virais/imunologia , Doença Aguda , Adolescente , Criança , Pré-Escolar , Dengue/fisiopatologia , Dengue/virologia , Vírus da Dengue/imunologia , Epitopos de Linfócito T/imunologia , Feminino , Antígenos HLA-B/imunologia , Humanos , Lactente , Células Matadoras Naturais/fisiologia , Leucócitos Mononucleares/imunologia , Masculino , Fragmentos de Peptídeos/metabolismo , Ligação Proteica , Proteínas não Estruturais Virais/metabolismo
6.
J Environ Manage ; 172: 171-6, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26945189

RESUMO

A field experiment was conducted from 2005 to 2008 in Fulton County, Western Illinois with biosolids from conventional wastewater treatment applied as corn fertilizer in a series of P rates (0, 163, 325, 488, 650 kg P ha(-1)) along with commercial P fertilizer - triple superphosphate P (TSP) as reference to assess biosolids-P plant availability and potential loss to waterbodies through runoff. Air-dried biosolids and TSP were incorporated into surface soil at end of 2005, and corn (Zea mays) was planted for three consecutive years (2006-2008). Concentrations of soil extractable P except for Mehlich-3 P were always lower in the biosolids than TSP treatments at the same P rates. The soil potentially available P in water extractable P (WEP) and Olsen P derived from biosolids-P estimated by the exponential depletion model was 2-4% and 15-24% of total P in the applied biosolids, respectively. The residence time of biosolids-induced WEP and Olsen P in Midwest soil under annual corn cropping was 5 and 2 years, respectively. Corn tissue analysis showed lower increase in P concentration by biosolids-P than TSP. The elevation rate of soluble reactive P (SRP) concentration in simulated runoff was less by biosolids than TSP. Based on the data in this study, the plant availability and environmental risk of biosolids-P are lower than those of TSP in the Midwest soil, thus use of biosolids as P nutrient for corn would not cause a major impairment to water sources even P applied through biosolids was not completely used by annual crop.


Assuntos
Fertilizantes , Fósforo/farmacocinética , Solo/química , Águas Residuárias/química , Zea mays , Disponibilidade Biológica , Difosfatos , Fertilizantes/análise , Illinois , Fósforo/análise , Medição de Risco/métodos , Poluentes Químicos da Água/análise
7.
Respir Res ; 16: 81, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-26122139

RESUMO

BACKGROUND: Vitamin D is associated with lung function in cross-sectional studies, and vitamin D inadequacy is hypothesized to play a role in the pathogenesis of chronic obstructive pulmonary disease. Further data are needed to clarify the relation between vitamin D status, genetic variation in vitamin D metabolic genes, and cross-sectional and longitudinal changes in lung function in healthy adults. METHODS: We estimated the association between serum 25-hydroxyvitamin D [25(OH)D] and cross-sectional forced expiratory volume in the first second (FEV1) in Framingham Heart Study (FHS) Offspring and Third Generation participants and the association between serum 25(OH)D and longitudinal change in FEV1 in Third Generation participants using linear mixed-effects models. Using a gene-based approach, we investigated the association between 241 SNPs in 6 select vitamin D metabolic genes in relation to longitudinal change in FEV1 in Offspring participants and pursued replication of these findings in a meta-analyzed set of 4 independent cohorts. RESULTS: We found a positive cross-sectional association between 25(OH)D and FEV1 in FHS Offspring and Third Generation participants (P=0.004). There was little or no association between 25(OH)D and longitudinal change in FEV1 in Third Generation participants (P=0.97). In Offspring participants, the CYP2R1 gene, hypothesized to influence usual serum 25(OH)D status, was associated with longitudinal change in FEV1 (gene-based P<0.05). The most significantly associated SNP from CYP2R1 had a consistent direction of association with FEV1 in the meta-analyzed set of replication cohorts, but the association did not reach statistical significance thresholds (P=0.09). CONCLUSIONS: Serum 25(OH)D status was associated with cross-sectional FEV1, but not longitudinal change in FEV1. The inconsistent associations may be driven by differences in the groups studied. CYP2R1 demonstrated a gene-based association with longitudinal change in FEV1 and is a promising candidate gene for further studies.


Assuntos
Proteínas de Ligação a DNA/sangue , Proteínas de Ligação a DNA/genética , Variação Genética/fisiologia , Redes e Vias Metabólicas/fisiologia , Proteínas Nucleares/sangue , Proteínas Nucleares/genética , Vitamina D/análogos & derivados , Adulto , Idoso , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Masculino , Massachusetts , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Fatores de Transcrição , Vitamina D/sangue , Vitamina D/genética
8.
Genes Immun ; 15(7): 440-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24989671

RESUMO

Members of the human KIR (killer cell immunoglobulin-like receptor) class I major histocompatibility complex receptor gene family contain multiple promoters that determine the variegated expression of KIR on natural killer cells. In order to identify novel genetic alterations associated with decreased KIR expression, a group of donors was characterized for KIR gene content, transcripts and protein expression. An individual with a single copy of the KIR2DL1 gene but a very low level of gene expression was identified. The low expression phenotype was associated with a single-nucleotide polymorphism (SNP) that created a binding site for the inhibitory ZEB1 (Zinc finger E-box-binding homeobox 1) transcription factor adjacent to a c-Myc binding site previously implicated in distal promoter activity. Individuals possessing this SNP had a substantial decrease in distal KIR2DL1 transcripts initiating from a novel intermediate promoter located 230 bp upstream of the proximal promoter start site. Surprisingly, there was no decrease in transcription from the KIR2DL1 proximal promoter. Reduced intermediate promoter activity revealed the existence of alternatively spliced KIR2DL1 transcripts containing premature termination codons that initiated from the proximal KIR2DL1 promoter. Altogether, these results indicate that distal transcripts are necessary for KIR2DL1 protein expression and are required for proper processing of sense transcripts from the bidirectional proximal promoter.


Assuntos
Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Receptores KIR2DL1/genética , Sequência de Bases , Sítios de Ligação , Linhagem Celular Tumoral , Células Cultivadas , Células HEK293 , Proteínas de Homeodomínio/metabolismo , Humanos , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores KIR2DL1/química , Receptores KIR2DL1/metabolismo , Fatores de Transcrição/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco
9.
Clin Exp Allergy ; 44(6): 851-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24397611

RESUMO

BACKGROUND: Mouse models of atopic march suggest that systemic, skin-derived thymic stromal lymphopoietin (TSLP) mediates progression from eczema to asthma. OBJECTIVE: We investigated whether circulating TSLP is associated with eczema, allergic sensitization, or recurrent wheezing in young children. METHODS: A prospective analysis of the relationship between plasma levels of TSLP to allergic sensitization and recurrent wheezing was conducted in the birth cohort from the Urban Environment and Childhood Asthma (URECA) study. Plasma TSLP levels were measured at 1, 2, and 3 years of age and analysed for correlation with clinical parameters in each of the three years. Only those children with consecutive samples for all three years were included in this analysis. RESULTS: We detected TSLP in 33% of 236 children for whom plasma samples were available for all three years. Overall, a consistently significant association was not found between TSLP and eczema or allergic sensitization. With regard to recurrent wheezing, children with detectable TSLP at one year of age were significantly less likely to experience recurrent wheezing by 3 years compared with those children without detectable TSLP, but this was only seen in children without aeroallergen sensitization at 3 years (P < 0.01). CONCLUSIONS AND CLINICAL RELEVANCE: Contrary to our expectations, circulating TSLP was not significantly associated with eczema, allergen sensitization, or recurrent wheezing during the first three years of life. Early presence of circulating TSLP was significantly associated with reduced incidence of recurrent wheeze in those children not sensitized to aeroallergen. These findings suggest a possible underlying distinction between pathogenesis of developing atopic vs. non-atopic recurrent wheeze.


Assuntos
Citocinas/sangue , Sons Respiratórios/etiologia , Alérgenos/imunologia , Pré-Escolar , Eczema/sangue , Eczema/etiologia , Feminino , Humanos , Hipersensibilidade/sangue , Hipersensibilidade/etiologia , Lactente , Masculino , Razão de Chances , Estudos Prospectivos , Linfopoietina do Estroma do Timo
10.
Rev Sci Instrum ; 95(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38829217

RESUMO

Blood testing using flow cytometry is a common and rapid method for the initial screening and diagnosis of patients. Measurements are often combined with other scientific techniques, and analyzed samples are commonly diluted and discarded afterward. When the sample is recollected instead, sample dilution is a challenge when the sample is intended or needed for additional measurements. Therefore, it is advantageous to recollect the undiluted sample. In order to enable measurements of the same undiluted sample aliquot, we designed and constructed a purpose-built flow cytometer. Our instrument employs syringes, acoustic focusing, and an open fluidics system to recollect and reuse the unadulterated sample. The cytometer is compact, which reduces sample consumption. It acquires forward, sideward, and fluorescence signals, offering opportunities for diverse measurement approaches. In particular, our cytometer has been designed to be ready for additional downstream analysis of cells, e.g., applying mass spectrometry, magnetic resonance spectroscopy, or other analytical tools. This study presents results on instrument performance, a comparison with a cytometer that uses standard hydrodynamic focusing, and a proof of concept for multiple measurements.


Assuntos
Citometria de Fluxo , Citometria de Fluxo/instrumentação , Citometria de Fluxo/métodos , Humanos , Desenho de Equipamento
11.
Radiography (Lond) ; 30(2): 628-633, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38330895

RESUMO

INTRODUCTION: Computed tomography (CT) imaging has become indispensable in the management of medical oncology patients. Risks associated with high cumulative effective dose (CED) are relevant in testicular cancer patients. Split-bolus protocols, whereby the contrast medium injection is divided into two, followed by combining the required phase images in a single scan acquisition has been shown to provide images of comparable image quality and less radiation dose compared to single-bolus split-phase CT for various indications. We retrospectively evaluated the performance of split-bolus and single-bolus protocols in patients having follow-up CT imaging for testicular cancer surveillance. METHODS: 45 patients with testicular cancer undergoing surveillance CT imaging of the thorax, abdomen, and pelvis who underwent split-bolus and single-bolus protocols were included. Quantitative image quality analysis was conducted by placing region of interests in pre-defined anatomical sub-structures within the abdominal cavity. The signal-to-noise ratio (SNR) and radiation dose in the form of dose length product (DLP) and effective dose (ED) were recorded. RESULTS: The DLP and ED for the single-bolus, split-phase acquisition was 506 ± 89 mGy cm and 7.59 ± 1.3 mSv, respectively. For the split-bolus, single-phase acquisition, 397 ± 94 mGy∗cm and 5.95 ± 1.4 mSv, respectively (p < 0.000). This represented a 21.5 % reduction in radiation dose exposure. The SNR for liver, muscle and fat for the single-bolus were 7.4, 4.7 and 8, respectively, compared to 5.5, 3.8 and 7.4 in the split-bolus protocol (p < 0.001). CONCLUSION: In a testicular cancer patient cohort undergoing surveillance CT imaging, utilization of a split-bolus single-phase acquisition CT protocol enabled a significant reduction in radiation dose whilst maintaining subjective diagnostic acceptability. IMPLICATIONS FOR PRACTICE: Use of split-bolus, single-phase acquisition has the potential to reduce CED in surveillance of testicular cancer patients.


Assuntos
Neoplasias Embrionárias de Células Germinativas , Neoplasias Testiculares , Masculino , Humanos , Estudos Retrospectivos , Neoplasias Testiculares/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Meios de Contraste
12.
Biomarkers ; 18(3): 196-203, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23557128

RESUMO

CONTEXT: Endothelial function is abnormal in chronic obstructive pulmonary disease (COPD); whether endothelial dysfunction causes COPD is unknown. OBJECTIVE: Test associations of endothelial biomarkers with FEV1 using instrumental variables. METHODS: Among 26 907 participants with spirometry, ICAM-1, P-selectin, E-selectin and endothelin-1 were measured in subsets. RESULTS: ICAM-1 and P-selectin were inversely associated with FEV1 among European-Americans (-29 mL and -34 mL per standard deviation of log-transformed biomarker, p < 0.001), as was endothelin-1 among African-Americans (-22 mL, p = 0.008). Genetically-estimated ICAM-1 and P-selectin were not significantly associated with FEV1. The instrumental variable for endothelin-1 was non-informative. CONCLUSION: Although ICAM-1, P-selectin and endothelin-1 were inversely associated with FEV1, associations for ICAM-1 and P-selectin do not appear causal.


Assuntos
Endotélio Vascular/metabolismo , Expressão Gênica , Pulmão/metabolismo , Doença Pulmonar Obstrutiva Crônica/genética , Biomarcadores/metabolismo , População Negra , Estudos de Coortes , Selectina E/genética , Selectina E/metabolismo , Endotelina-1/genética , Endotelina-1/metabolismo , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Selectina-P/genética , Selectina-P/metabolismo , Doença Pulmonar Obstrutiva Crônica/etnologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Testes de Função Respiratória , Espirometria , População Branca
13.
Ir Med J ; 106(10): 314-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24579414

RESUMO

Bronchiolitis affects one third of babies in their first year of life. We investigated all bronchiolitis admissions to Tallaght Hospital in the last five years, with the hope of providing an insight into the epidemic in an Irish population. We analysed these 1,202 admissions on the basis of time of year (busiest being December at 24.20%), length of stay (mean 2.92 days), gender (62% male) and age (mean 30.29 weeks). There was a 102% increase in the average incidence of bronchiolitis in the first six months of 2011 and 2012 (186) compared to the previous four years (92.25). P value was statistically significant at 0.0469. Our findings were backed up by comparable data from OLCH, Crumlin (149.5 for 2011-2012 vs 36.25 for 2007-2010). There has been in a significant shift in the timing and incidence of bronchiolitis in Tallaght Hospital in the last two years. We explored the possible reasons for this, with special attention to RSV incidence, climate causes and vaccine programs.


Assuntos
Bronquiolite/epidemiologia , Surtos de Doenças/estatística & dados numéricos , Feminino , Humanos , Lactente , Irlanda/epidemiologia , Tempo de Internação , Masculino
14.
J Child Health Care ; : 13674935231185181, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37406354

RESUMO

This systematic review summarises evidence regarding oral nutritional supplement (ONS) use in children with, or at risk of, faltering growth (FG). Ten randomised controlled trials (RCTs), compared changes in outcomes amongst children receiving ONS versus control were included. Overall, 1116 children (weighted mean (WM) age 5 years; n658 (59%) male) were recruited, of which 585 (52%) received ONS (WM intake contribution 412 kcal, 16.3 g protein, 395 ml) for 116 days (WM). ONS use was associated with significantly greater gains in weight (mean difference (MD) 0.4 kg, 95% CI [0.36, 0.44]) and height (MD 0.3 cm, 95% CI [0.03, 0.57]), likely related to improvements in nutritional intake. Mean compliance to prescribed dose was 98%. Data suggested an association between ONS use and reduced infections. Further research is warranted to establish ONS dosage and effects upon other outcomes. This review provides evidence to support use of ONS in the management of children with, or at risk of, FG.

15.
J Nanosci Nanotechnol ; 12(11): 8656-61, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23421260

RESUMO

Understanding the formation and evolution of nanoparticles generated during laser ablation is imperative in controlling the health risk associated with the ablated material, minimizing contamination and enhancing ablation rates. There is also a keen interest in undertaking a competitive analysis of nanoparticle generation compared with current synthesis techniques. Laser-material-ambient interactions are, however, complex due to the dynamic nature of the ablation environment and consequently it is difficult to characterize the process of nanoparticle formation and evolution. Al, Ni and Au films with thicknesses of 10, 25 and 75 nm were ablated by single nano- and femto-second laser pulses. Generated nanoparticles were collected and their height and diameter measured using AFM and SEM, respectively. Results identified that the thickness of the metal film is highly influential on the size and distribution of nanoparticles e.g., mean radius for Au nanoparticles generated during femtosecond laser ablation of 75, 25 and 10 nm thick films were 5.9 nm, 3.5 nm and 1.8 nm, respectively. The standard deviation (sigma) of radii of these nanoparticles generated from 75, 25 and 10 nm thick films also decreased from 8 nm, 6 nm to 1 nm, respectively.


Assuntos
Lasers , Membranas Artificiais , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Titânio/química , Teste de Materiais , Nanopartículas Metálicas/efeitos da radiação , Conformação Molecular/efeitos da radiação , Tamanho da Partícula , Doses de Radiação , Propriedades de Superfície/efeitos da radiação
16.
Clin Exp Allergy ; 41(6): 842-50, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21481021

RESUMO

BACKGROUND: Recent studies have reported conflicting data on the association between maternal intake of vitamin D during pregnancy and asthma. OBJECTIVE: To assess the influence of prenatal vitamin D status on immune function at birth. METHODS: In an inner-city birth cohort of 568 newborns, 520 of whom had at least one atopic parent, we measured the umbilical cord (UC) plasma concentration of 25-hydroxyvitamin D (25(OH)D) and the cytokine responses of UC blood mononuclear cells (UCMCs) to stimuli including phytohaemagglutinin (PHA), lipopolysaccharide (LPS), and peptidoglycan. In a subset, the UCMC expression of regulatory T cell markers and the suppressive activity of CD4(+) CD25(+) UCMCs were measured. Results The 25th, 50th, and 75th percentiles of UC plasma 25(OH)D level were 15.0, 20.2, and 25.6 ng/mL, respectively. Most cytokine responses of UCMC were not correlated with UC 25(OH)D concentration; however, IFN-γ release after LPS stimulation was weakly positively correlated with UC 25(OH)D concentration (r=0.11, P=0.01). PHA responses were not significantly correlated with 25(OH)D concentration. The UC plasma 25(OH)D concentration was inversely related to the number of CD25(+) (r=-0.20, P=0.06), CD25(Bright) (r=-0.21, P=0.05), and CD25(+) FoxP3 (r=-0.29, P=0.06) cells as a proportion of CD4(+) T cells in UC blood (r=-0.26, P=0.04) but not to the suppressive activity of CD4(+) CD25(+) cells (r=0.17, P=0.22). CONCLUSION AND CLINICAL RELEVANCE: UC 25(OH)D concentration was not correlated with most UCMC cytokine responses to multiple stimuli. There was a suggestion of a weakly positive correlation with IFN-γ release after LPS stimulation. The proportions of CD25(+) , CD25(Bright) , and CD25(+) FoxP3 cells to total CD4(+) T cells were inversely correlated with UC 25(OH)D concentration. Our findings suggest that higher vitamin D levels at birth may be associated with a lower number of T-regulatory cells. Vitamin D status in utero may influence immune regulation in early life.


Assuntos
Asma/sangue , Asma/imunologia , Sangue Fetal/imunologia , Sistema Imunitário/imunologia , Saúde da População Urbana , Vitamina D/análogos & derivados , Adolescente , Adulto , Asma/epidemiologia , Citocinas/metabolismo , Feminino , Humanos , Recém-Nascido , Leucócitos Mononucleares/imunologia , Masculino , Fatores de Risco , Linfócitos T Reguladores/imunologia , Vitamina D/sangue , Vitamina D/imunologia , Adulto Jovem
17.
Allergy ; 65(12): 1566-75, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20560908

RESUMO

BACKGROUND: Single nucleotide polymorphisms (SNPs) in thymic stromal lymphopoietin (TSLP) have been associated with IgE (in girls) and asthma (in general). We sought to determine whether TSLP SNPs are associated with asthma in a sex-specific fashion. METHODS: We conducted regular and sex-stratified analyses of association between SNPs in TSLP and asthma in families of children with asthma in Costa Rica. Significant findings were replicated in whites and African-American participants in the Childhood Asthma Management Program, in African-Americans in the Genomic Research on Asthma in the African Diaspora study, in whites and Hispanics in the Children's Health Study, and in whites in the Framingham Heart Study (FHS). MAIN RESULTS: Two SNPs in TSLP (rs1837253 and rs2289276) were significantly associated with a reduced risk of asthma in combined analyses of all cohorts (P values of 2 × 10(-5) and 1 × 10(-5) , respectively). In a sex-stratified analysis, the T allele of rs1837253 was significantly associated with a reduced risk of asthma in males only (P = 3 × 10(-6) ). Alternately, the T allele of rs2289276 was significantly associated with a reduced risk of asthma in females only (P = 2 × 10(-4) ). Findings for rs2289276 were consistent in all cohorts except the FHS. CONCLUSIONS: TSLP variants are associated with asthma in a sex-specific fashion.


Assuntos
Asma/genética , Citocinas/genética , Predisposição Genética para Doença/genética , Caracteres Sexuais , População Negra/genética , Criança , Estudos de Coortes , Costa Rica , Feminino , Predisposição Genética para Doença/etnologia , Estudo de Associação Genômica Ampla , Genótipo , Hispânico ou Latino/genética , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Fatores de Risco , População Branca/genética , Linfopoietina do Estroma do Timo
18.
Analyst ; 135(4): 731-7, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20349538

RESUMO

In desorption electrospray ionisation (DESI) the interaction between the electrospray and the surface is key to two important analytical parameters, the spatial resolution and the sensitivity. We evaluate the effect of the electrospray solvent type, organic solvent fraction with water, analyte solubility and substrate wettability on DESI erosion diameter and material transferral into useful ion signal. To do this five amino acids, glycine, alanine, valine, leucine and phenylalanine are prepared as thin films on three substrates, UV/ozone treated glass, glass and polytetrafluoroethylene (PTFE). Four different solvents, acetonitrile (ACN), methanol (MeOH), ethanol (EtOH) and propan-2-ol (IPA), are used with organic solvent fractions with water varying from 0.1 to 1. These model systems allow the solubility or wettability to be kept constant as other parameters are varied. Additionally, comparison with electrospray ionisation (ESI) allows effects of ionisation efficiency to be determined. It is shown that the DESI efficiency is linearly dependent on the solubility (for these materials at least) and for analytes with solubilities below 1.5 g kg(-1), additional strategies may be required for DESI to be effective. We show that the DESI erosion diameter improves linearly with organic solvent fraction, with an organic solvent fraction of 0.9 instead of 0.5 leading to a 2 fold improvement. Furthermore, this leads to a 35 fold increase in DESI efficiency, defined as the molecular ion yield per unit area. It is shown that these improvements correlate with smaller droplet sizes rather than surface wetting or ionisation.

19.
Epilepsy Behav Rep ; 14: 100375, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32671335

RESUMO

Reflex epilepsies are rare syndromes where seizures are triggered by particular stimuli or activities that may be motor, sensory or cognitive in nature. Triggers are diverse, may be extrinsic or intrinsic in nature and heterogeneous phenotypes have been described over the years. We give an account of a case of location-specific reflex epilepsy which we suggest is a novel reflex epilepsy phenotype relating to higher cortical function (HCF), and review the literature in relation to features of HCF reflex epilepsies described to date.

20.
Artigo em Inglês | MEDLINE | ID: mdl-32265838

RESUMO

The Karlberg model of human growth describes the infancy, childhood, and puberty (ICP) stages as continuous and overlapping, and defined by transitions driven by sequential additional effects of several endocrine factors that shape the growth trajectory and resultant adult size. Previous research has suggested that a delayed transition from the infancy to the childhood growth stage contributes to sub-optimal growth outcomes. A new method developed to analyze the structure of centile crossing in early life has emerged as a potential tool for identifying the infancy-childhood transition (ICT), through quantifying patterns of adjacent monthly weight-for-age z-score (WAZ) deviation correlations. Using this method, the infancy-childhood transition was identified as taking place at around 12 months of age in two cohorts of UK infants. Here, we apply this method to data collected as part of a longitudinal growth study in rural Gambia [the Hormonal and Epigenetic Regulators of Growth, or HERO-G study, N = 212 (F = 99, M = 113)], in order to identify the ICT and assess whether timing of this transition differs across groups based on sex or birth seasonality. We calculated Pearson correlation coefficients for adjacent monthly WAZ score deviations. Based on the patterns of change in the correlation structure over time, our results suggest that the infancy-childhood transition occurs at around 9 months of age in rural Gambian infants. This points to an accelerated ICT compared to UK infants, rather than a delayed ICT. A comparatively later transition, seen in UK infants, allows maximal extension of the high rates of growth during the infancy stage; an earlier transition as seen in Gambian infants cuts short this period of rapid growth, potentially impacting on growth outcomes in childhood while diverting energy into other processes critical to responses to acute infectious challenges. Growth in later developmental stages in this population offers an extended window for catch-up.


Assuntos
Estatura , Peso Corporal , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Fatores de Tempo
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