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1.
Allergy ; 73(7): 1515-1524, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29318631

RESUMO

BACKGROUND: Gut microbiota may play a role in egg allergy. We sought to examine the association between early-life gut microbiota and egg allergy. METHODS: We studied 141 children with egg allergy and controls from the multicenter Consortium of Food Allergy Research study. At enrollment (age 3 to 16 months), fecal samples were collected, and clinical evaluation, egg-specific IgE measurement, and egg skin prick test were performed. Gut microbiome was profiled by 16S rRNA sequencing. Analyses for the primary outcome of egg allergy at enrollment, and the secondary outcomes of egg sensitization at enrollment and resolution of egg allergy by age 8 years, were performed using Quantitative Insights into Microbial Ecology, Phylogenetic Investigation of Communities by Reconstruction of Unobserved States, and Statistical Analysis of Metagenomic Profiles. RESULTS: Compared to controls, increased alpha diversity and distinct taxa (PERMANOVA P = 5.0 × 10-4 ) characterized the early-life gut microbiome of children with egg allergy. Genera from the Lachnospiraceae, Streptococcaceae, and Leuconostocaceae families were differentially abundant in children with egg allergy. Predicted metagenome functional analyses showed differential purine metabolism by the gut microbiota of egg-allergic subjects (Kruskal-Wallis Padj  = 0.021). Greater gut microbiome diversity and genera from Lachnospiraceae and Ruminococcaceae were associated with egg sensitization (PERMANOVA P = 5.0 × 10-4 ). Among those with egg allergy, there was no association between early-life gut microbiota and egg allergy resolution by age 8 years. CONCLUSION: The distinct early-life gut microbiota in egg-allergic and egg-sensitized children identified by our study may point to targets for preventive or therapeutic intervention.


Assuntos
Hipersensibilidade a Ovo/etiologia , Microbioma Gastrointestinal , Fatores Etários , Estudos de Casos e Controles , Feminino , Microbioma Gastrointestinal/imunologia , Humanos , Imunização , Imunoglobulina E/imunologia , Lactente , Masculino , Metagenoma , Metagenômica , RNA Ribossômico 16S
2.
Phys Chem Chem Phys ; 20(8): 5827-5840, 2018 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-29412206

RESUMO

The D- and G-band Raman signals from random arrays of vertically aligned, multi-walled carbon nanotubes are significantly enhanced (up to ∼14×) while the signal from the underlying Si substrate is simultaneously attenuated (up to ∼6×) when the nanotubes are dressed, either capped or coated, with Ag. These Ag-induced counter-changes originate with the difference in geometry of the nanotubes and planar Si substrate and contrast in the Ag depositions on the substrate (essentially thin film) and the nanotube (nano-particulate). The surface integral equation technique is used to perform detailed modelling of the electromagnetic response of the system in a computationally efficient manner. Within the modelling the overall antenna response of the Ag-dressed nanotubes is shown to underpin the main contribution to enhancement of the nanotube Raman signal with hot-spots between the Ag nanoparticles making a subsidiary contribution on account of their relatively weak penetration into the nanotube walls. Although additional hot-spot activity likely accounts for a shortfall in modelling relative to experiment it is nonetheless the case that the significant antenna-driven enhancement stands in marked contrast to the hot-spot dominated enhancement of the Raman spectra from molecules adsorbed on the same Ag-dressed structures. The Ag-dressing procedure for amplifying the nanotube Raman output not only allows for ready characterisation of individual nanotubes, but also evidences a small peak at ∼1150 cm-1 (not visible for the bare, undressed nanotube) which is suggested to be due to the presence of trans-polyacetylene in the structures.

3.
Colorectal Dis ; 20(1): 68-73, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28682454

RESUMO

AIM: In order to develop its education agenda, the Association of Coloproctology of Great Britain and Ireland (ACPGBI) sought the opinion of its members on current coloproctology training needs. The aims of this study were to canvass multidisciplinary needs and explore the perceived gaps and barriers to meeting them. METHOD: A learner-needs analysis was performed between July 2015 and October 2016. A bespoke electronic survey was sent to 1453 colorectal healthcare professionals [ACPGBI membership (1173), colorectal nurse specialists and allied health professionals (NAHPs) (261) and regional chapter-leads (19)] seeking their needs, experiences and barriers to training across the coloproctology disciplines. RESULTS: In all, 390 responses were received [26.8% overall; 180 consultants/trainees (15%); 196 NAHPs (75%); 14 (74%) chapter-leads]. Lack of funding and difficulties in obtaining study leave were the most frequently reported barriers to course and conference attendance. Transanal total mesorectal excision and laparoscopic training were the top educational needs for consultants and trainees respectively. 79% of NAHP respondents reported education gaps on a broad range of clinical and non-clinical topics. NAHPs lacked information on relevant training opportunities and 27% felt available courses were insufficient to meet their educational needs. Wide heterogeneity in ACPGBI chapter composition and activity was reported. All groups felt the ACPGBI should increase the number of courses offered with coloproctology knowledge updates commonly requested. CONCLUSION: A series of training needs across the coloproctology disciplines have been identified. These will underpin the development of the educational agenda for the ACPGBI.


Assuntos
Cirurgia Colorretal/educação , Educação Médica Continuada/estatística & dados numéricos , Pessoal de Saúde/educação , Avaliação das Necessidades/estatística & dados numéricos , Atitude do Pessoal de Saúde , Cirurgia Colorretal/organização & administração , Humanos , Irlanda , Sociedades Médicas , Inquéritos e Questionários , Reino Unido
4.
Faraday Discuss ; 205: 121-148, 2017 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-28884781

RESUMO

Quantitative understanding of the electromagnetic component in enhanced Raman spectroscopy is often difficult to achieve on account of the complex substrate structures utilised. We therefore turn to two structurally simple systems amenable to detailed modelling. The first is tip-enhanced Raman scattering under electron scanning tunnelling microscopy control (STM-TERS) where, appealing to understanding developed in the context of photon emission from STM, it is argued that the localised surface plasmon modes driving the Raman enhancement exist in the visible and near-infrared regime only by virtue of significant modification to the optical properties of the tip and sample metals (gold here). This is due to the strong dc field-induced (∼109 V m-1) non-linear corrections to the dielectric function of gold via the third order susceptibility term in the polarisation. Also, sub-5 nm spatial resolution is shown in the modelling. Secondly, we suggest a novel deployment of hybrid plasmonic waveguide modes in surface enhanced Raman scattering (HPWG-SERS). This delivers strong confinement of electromagnetic energy in a ∼10 nm oxide 'gap' between a high-index dielectric material of nanoscale width (a GaAs nanorod and a 100 nm Si slab are considered here) and a metal, yielding a monotonic variation in the Raman enhancement factor as a function of wavelength with no long-wavelength cut-off, both features that contrast with STM-TERS.

5.
Epidemiol Infect ; 145(1): 156-169, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27671159

RESUMO

Accurate forecasting of seasonal influenza epidemics is of great concern to healthcare providers in temperate climates, since these epidemics vary substantially in their size, timing and duration from year to year, making it a challenge to deliver timely and proportionate responses. Previous studies have shown that Bayesian estimation techniques can accurately predict when an influenza epidemic will peak many weeks in advance, and we have previously tailored these methods for metropolitan Melbourne (Australia) and Google Flu Trends data. Here we extend these methods to clinical observation and laboratory-confirmation data for Melbourne, on the grounds that these data sources provide more accurate characterizations of influenza activity. We show that from each of these data sources we can accurately predict the timing of the epidemic peak 4-6 weeks in advance. We also show that making simultaneous use of multiple surveillance systems to improve forecast skill remains a fundamental challenge. Disparate systems provide complementary characterizations of disease activity, which may or may not be comparable, and it is unclear how a 'ground truth' for evaluating forecasts against these multiple characterizations might be defined. These findings are a significant step towards making optimal use of routine surveillance data for outbreak forecasting.


Assuntos
Epidemias , Monitoramento Epidemiológico , Previsões/métodos , Influenza Humana/epidemiologia , Austrália/epidemiologia , Humanos , Estudos Retrospectivos
6.
Allergy ; 71(11): 1552-1560, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27015954

RESUMO

BACKGROUND: In a previously reported CoFAR study, 55 subjects with egg allergy underwent randomized, placebo-controlled egg oral immunotherapy (eOIT). Active treatment induced desensitization in most and sustained unresponsiveness (SU) in a smaller subset. We hypothesized that component-resolved analysis of IgE, IgG4, IgA, IgA1, and IgA2 may identify potential biomarkers of SU in OIT subjects. METHODS: Longitudinal samples for 51 egg-allergic subjects (37 active and 14 placebo) were available. Egg white (EW)-, ovalbumin (OVA)-, and ovomucoid (OVM)-specific levels of IgA, IgA1, and IgA2 were quantified by ELISA. IgE and IgG4 to these antigens were quantified using ImmunoCAP® . Clinical responders achieved SU to egg; all others were considered nonresponders. Between-group comparisons were made among active and placebo, as well as responders and nonresponders. RESULTS: No placebo subjects achieved responder status. Through month 48, among the 37 active subjects, baseline IgE-OVM was lower in responders (median 3.97 kU/l, n = 19) than in nonresponders (10.9 kU/l, n = 18, P = 0.010). Logistic regression analysis revealed that lower baseline IgE-EW (P = 0.038), IgE-OVM (P = 0.032), and a higher IgG4/IgE-OVM ratio (P = 0.013) were associated with clinical response. Relative increases in IgG4-EW, IgA-EW, and IgA2-EW were observed in responders (P = 0.024, 0.024, and 0.029, respectively). IgG4/IgE, IgA/IgE, and IgA2/IgE ratios for EW and IgA/IgE ratio for OVA were found to be significantly elevated among responders (P = 0.004, 0.009, 0.028, and 0.008, respectively). CONCLUSIONS: Increased IgG4-EW, IgA-EW, and IgA2-EW during eOIT are associated with clinical response to eOIT. Lower pretreatment IgE-EW and IgE-OVM are also associated with SU. Future studies are needed to evaluate and validate these potential biomarkers.


Assuntos
Alérgenos/imunologia , Dessensibilização Imunológica , Hipersensibilidade a Ovo/imunologia , Hipersensibilidade a Ovo/terapia , Ovos/efeitos adversos , Imunoglobulina A/imunologia , Imunoglobulina E/imunologia , Imunoglobulina G/imunologia , Administração Oral , Alérgenos/administração & dosagem , Biomarcadores , Dessensibilização Imunológica/métodos , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina E/sangue , Imunoglobulina G/sangue , Masculino , Falha de Tratamento , Resultado do Tratamento
7.
Ir Med J ; 108(5): 153-4, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26062246

RESUMO

We aim to report our experience with out of hospital transfers for postoperative complications in a stand-alone elective orthopaedic hospital. We aim to describe the cohort of patients transferred, the rate of transfer and assess the risk factors for transfer. Patients were identified who were transferred out of the hospital to another acute hospital for management of non-routine medical problems. Patient data was collected relating to age, BMI, ASA, type of surgery, nature of the complication, timing and the outcome of transfer. In 2012, 2,853 inpatient surgical procedures were carried out, 51 patients (1.8%) developed a postoperative complication that required out of hospital transfer. Mean age of patients transferred was 67 (12-86) years, mean age of the overall case mix 58 years (0-96) (p = 0.01). 37.7% of the overall case mix of surgeries was made up of primary hip and knee arthroplasty procedures, these patients made up 63.7% of patients transferred out (p = 0.001). Mean BMI recorded was 31.7 (22-48) compared to the mean BMI of the total arthroplasty case mix of 28.8 (20-44) (p = 0.02). 59% of all patients at our institution were ASA category II or III. 76% of patients transferred were ASA category II or III (p = 0.005). We can conclude that patients requiring transfer are typically older. Arthroplasty patients are more likely to require transfer than patients undergoing other orthopaedic procedures. Among the arthroplasty cohort transferred patients will typically have a higher BMI than average. Patients with ASA category II or III make up nearly three quarters of those patients transferred. The mean age of patients transferred is typically older by 9 years.


Assuntos
Cuidados Críticos , Procedimentos Cirúrgicos Eletivos , Hospitais Especializados , Procedimentos Ortopédicos , Transferência de Pacientes/estatística & dados numéricos , Complicações Pós-Operatórias , Fatores Etários , Idoso , Índice de Massa Corporal , Cuidados Críticos/métodos , Cuidados Críticos/organização & administração , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Procedimentos Cirúrgicos Eletivos/métodos , Feminino , Hospitais Especializados/métodos , Hospitais Especializados/estatística & dados numéricos , Humanos , Irlanda , Masculino , Avaliação das Necessidades , Procedimentos Ortopédicos/efeitos adversos , Procedimentos Ortopédicos/métodos , Ortopedia , Avaliação de Resultados em Cuidados de Saúde , Transferência de Pacientes/métodos , Complicações Pós-Operatórias/classificação , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/terapia , Fatores de Risco , Fatores de Tempo
8.
West Indian Med J ; 64(4): 432-4, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26624601

RESUMO

BACKGROUND: Osteogenesis imperfecta, also known as 'brittle bone disease', is a genetic connective tissue disease. It is characterized by bone fragility and osteopenia (low bone density). In this case, a 57-year old female presented to the University Hospital of the West Indies (UHWI), Physical Medicine and Rehabilitation Clinic with left low back pain rated 6/10 on the numeric rating scale (NRS). Clinically, the patient had sacroiliac joint mediated pain although X-rays did not show the sacroiliac joint changes. Fluoroscopy-guided left sacroiliac joint steroid injection was done. METHODS: Numeric rating scale and Oswestry Disability Index (ODI) questionnaire were used to evaluate outcome. This was completed at baseline, one week follow-up and at eight weeks post fluoroscopy-guided sacroiliac joint steroid injection. RESULTS: Numeric rating scale improved from 6/10 before the procedure to 0/10 post procedure, and ODI questionnaire score improved from a moderate disability score of 40% to a minimal disability score of 13%. Up to eight weeks, the NRS was 0/10 and ODI remained at minimal disability of 15%. CONCLUSION: Fluoroscopy-guided sacroiliac joint injection is a known diagnostic and treatment method for sacroiliac joint mediated pain. To our knowledge, this is the first case published on the use of fluoroscopy-guided sacroiliac joint steroid injection in the treatment of sacroiliac joint mediated low back pain in a patient with osteogenesis imperfecta.

9.
Colorectal Dis ; 16(6): O197-205, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24344746

RESUMO

AIM: Up to a quarter of patients with rectal cancer have synchronous liver metastases at the time of diagnosis. This is a predictor of poor outcome. There are no standardized guidelines for treatment. We reviewed the outcomes of our patients with synchronous rectal liver metastases treated with a curative intent by neoadjuvant chemotherapy with or without chemoradiotherapy followed by resection of the primary tumour and then liver metastases. METHOD: Between 2004 and 2012, patients who presented with rectal cancer and synchronous liver metastasis were treated with curative intent with peri-operative systemic chemotherapy as the first line of treatment. Responders to chemotherapy underwent resection of the primary tumour with or without preoperative chemoradiotherapy followed by hepatic resection. RESULTS: Fifty-three rectal cancer patients with 152 synchronous liver lesions were identified. After a median follow-up of 29.6 months, the median survival was 41.4 months. Overall survival was 59.0% at 3 years and 39.0% at 5 years. CONCLUSION: Rectal resection before hepatic resection combined with neoadjuvant chemotherapy is associated with promising clinical outcome. It allows downstaging of liver lesions and removal of the primary tumour before the progression of further micrometastases. Furthermore, patients who do not respond to chemotherapy can be identified and may avoid major surgical intervention.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Hepáticas/terapia , Cuidados Pré-Operatórios/métodos , Neoplasias Retais/terapia , Adulto , Idoso , Colectomia , Diagnóstico por Imagem , Feminino , Seguimentos , Hepatectomia , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Estadiamento de Neoplasias , Neoplasias Retais/diagnóstico , Neoplasias Retais/secundário , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Resultado do Tratamento , Reino Unido/epidemiologia
10.
Tech Coloproctol ; 18(10): 937-43, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25037073

RESUMO

BACKGROUND: Magnetic resonance imaging (MRI) is known to have high predictive accuracy for circumferential resection margin (CRM) involvement of pre-treatment rectal tumours. This study aims to assess predictive accuracy of MRI for CRM involvement in rectal cancers post-long-course chemoradiotherapy (CRT) and in particular to understand how this information can influence surgical planning. METHODS: Forty-seven rectal cancers treated with CRT followed by bowel resection in one hospital since 2005 were reviewed for clinical, radiological and pathological characteristics. Using a validated pro forma, a radiologist blinded to final histology and original MRI report predicted CRM status from post-CRT MRI images. Results were compared to histological CRM status of final specimen, and differential analysis by type of surgical operation was performed. RESULTS: Overall accuracy of MRI for CRM involvement post-CRT was 72 % with a negative predictive value of 92 %. Abdominoperineal excision (APE) post-CRT was associated with non-significantly higher rates of histologically involved CRM than anterior resection (AR; 41 vs. 21 %) as were mucinous adenocarcinomas when compared to non-mucinous (56 vs. 21 %). Overall accuracy and positive predictive value were non-significantly higher for cancer treated with a standard APE than AR, and negative predictive value was high for both groups. CONCLUSIONS: MRI post-CRT has high negative predictive value for CRM status. Such information is of particular clinical relevance in low rectal cancers treated with APE as it can indicate when a standard surgical approach is likely to be sufficient.


Assuntos
Imageamento por Ressonância Magnética , Neoplasias Retais/cirurgia , Adenocarcinoma Mucinoso/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimiorradioterapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Estudos Retrospectivos
11.
West Indian Med J ; 63(1): 109-11, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25303203

RESUMO

Sacroiliitis, a condition commonly seen in Ankylosing Spondylitis, is well known to be one of the main pain generators of low back pain, which may result in difficulty with walking. A 20-year old male with history of ankylosing spondylitis presented to the University Hospital of the West Indies, Physical Medicine and Rehabilitation clinic, with a two-year history of right buttock, low back and groin pain. Radiographic evaluation revealed increased sclerosis and erosive changes in bilateral sacroiliac joints, right greater than left. Right intra-articular sacroiliac joint steroid injection was administered under fluoroscopy guidance. Post-injection visual analogue pain scale (VAS) score with activity improved from 8 to 1 and Oswestry Disability Index improved from 40% moderate disability to 16% minimal disability. The patient's overall assessment was 95% perceived improvement in pain. This case report illustrates the effectiveness of intra-articular sacroiliac joint steroid injection in treating sacroiliitis in ankylosing spondylitis.

12.
Biochem Biophys Res Commun ; 433(1): 79-83, 2013 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-23485456

RESUMO

The human solute linked carrier (SLC) 13A4 gene is primarily expressed in the placenta where it is proposed to mediate the transport of nutrient sulfate from mother to fetus. The molecular mechanisms involved in the regulation of SLC13A4 expression remain unknown. To investigate the regulation of SLC13A4 gene expression, we analysed the transcriptional activity of the human SLC13A4 5'-flanking region in the JEG-3 placental cell line using luciferase reporter assays. Basal transcriptional activity was identified in the region -57 to -192 nucleotides upstream of the SLC13A4 transcription initiation site. Mutational analysis of the minimal promoter region identified Nuclear factor Y (NFY), Specificity protein 1 (SP1) and Krüppel like factor 7 (KLF7) motifs which conferred positive transcriptional activity, as well as Zinc finger protein of the cerebellum 2 (ZIC2) and helix-loop-helix protein 1 (HEN1) motifs that repressed transcription. The conserved NFY, SP1, KLF7, ZIC2 and HEN1 motifs in the SLC13A4 promoter of placental species but not in non-placental species, suggests a potential role for these putative transcriptional factor binding motifs in the physiological control of SLC13A4 mRNA expression.


Assuntos
Proteínas de Transporte de Ânions/genética , Simportadores/genética , Região 5'-Flanqueadora , Sequência de Bases , Linhagem Celular , Sequência Conservada , Feminino , Regulação da Expressão Gênica , Genes Reporter , Humanos , Luciferases/genética , Mutagênese Sítio-Dirigida , Filogenia , Placenta/metabolismo , Gravidez , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transportadores de Sulfato , Transcrição Gênica
14.
Poult Sci ; 92(2): 444-53, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23300312

RESUMO

The aim of the present research was 1) to extract carnosine from different low economic value poultry tissues and 2) to measure their antioxidant activities using different analytical methods. Low economic value poultry tissues such as the head, liver, lungs, tail, gizzard, brain, and heart were used in this study. Results have indicated that carnosine was present in all the tissue samples investigated. The liver had the highest (102.29 mg/g) and brain the lowest carnosine content (0.95 mg/g; P ≤ 0.05). Except for the brain, all tissue ultrafiltrates and reconstituted dry powders showed TBA reactive species inhibition ranging from 20.87 to 39.57% and 5.66 -14.47%, respectively. Free radical scavenging activity of ultrafiltrate from all tissues samples ranged from 25.11 to 79.38%, whereas this activity was higher (29.76 to 84.05%) in the reconstituted dry powder of all tissue samples. Conclusions include that extraction of bioactive dipeptide carnosine can be exploited from low economic value poultry tissues to increase the economy of the poultry industry.


Assuntos
Antioxidantes/metabolismo , Carnosina/metabolismo , Quelantes/metabolismo , Galinhas/metabolismo , Radicais Livres/metabolismo , Animais , Especificidade de Órgãos , Tiobarbitúricos/química
15.
Soc Sci Med ; 335: 116228, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37722144

RESUMO

BACKGROUND: Maternal influenza and pertussis immunisation is crucial for protecting mothers during pregnancy and their babies in the first weeks of life against severe disease. We examined geospatial variation in maternal immunisation coverage among pregnant women in Aotearoa New Zealand and its health equity implications. METHOD: We constructed a retrospective cohort including all pregnant women who delivered between 01 January 2013 and 31 December 2020 using administrative health datasets. Our outcomes were receipt of influenza or pertussis vaccine in any one of three relevant national databases (e.g. National Immunisation Register, Proclaims, or Pharmaceutical collection) during the eligible pregnancy. RESULTS: Data from our retrospective cohort study show significant regional variation in maternal immunisation coverage for both influenza and pertussis from 2013 to 2020. Maximal coverage was around 50% in the best performing regions, which means that half of the women who were pregnant (183,737 women) were not protected. In addition, we found significant spatio-temporal variation and clustering of immunisation coverage. Our findings are interactively available to explore here: https://geohealthlab.shinyapps.io/hapumama/ CONCLUSION: Our study is one of the first to examine spatial variation in maternal vaccination coverage in pregnant women at a national level over space and time. This provides powerful tools to measure the impact of interventions to improve coverage at national and regional levels, with specific reference to inequities between ethnic groups, likely applicable to similar settings internationally.

16.
Nano Lett ; 11(2): 365-71, 2011 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-21265550

RESUMO

The electric field enhancement associated with detailed structure within novel optical antenna nanostructures is modeled using the surface integral equation technique in the context of surface-enhanced Raman scattering (SERS). The antennae comprise random arrays of vertically aligned, multiwalled carbon nanotubes dressed with highly granular Ag. Different types of "hot-spot" underpinning the SERS are identified, but contrasting characteristics are revealed. Those at the outer edges of the Ag grains are antenna driven with field enhancement amplified in antenna antinodes while intergrain hotspots are largely independent of antenna activity. Hot-spots between the tops of antennae leaning towards each other also appear to benefit from antenna amplification.


Assuntos
Cristalização/métodos , Nanotecnologia/instrumentação , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Prata/química , Ressonância de Plasmônio de Superfície/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
17.
Rural Remote Health ; 12: 2256, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22985135

RESUMO

The 50th annual National Scientific Conference of the Australian Society for Medical Research was held in Cairns, Queensland, 13-16 November 2011. The theme, 'Indigenous Health: ACTION on Prevention' highlighted the direct action being undertaken by health and medical researchers, as well as allied health professionals, to improve long-term health outcomes for Indigenous Australians.


Assuntos
Ocupações Relacionadas com Saúde , Serviços de Saúde do Indígena , Garantia da Qualidade dos Cuidados de Saúde , Sociedades Médicas , Pesquisa sobre Serviços de Saúde , Humanos , Queensland , Pesquisadores
18.
Oper Dent ; 36(5): 460-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21859318

RESUMO

This randomized clinical study assessed efficacy in terms of color change and production of sensitivity after home whitening alone and home whitening supplemented with in-office bleaching. Thirty-six subjects (aged 19 to 58 years) were randomly assigned to one of three different treatment groups: (A) home whitening for two weeks, with 16% carbamide peroxide in custom-made trays; (B) home whitening for two weeks, with 16% carbamide peroxide in custom-made trays supplemented with in-office bleaching with 9% hydrogen peroxide (in the same trays); or (C) home whitening for two weeks, with 16% carbamide peroxide in custom-made trays supplemented with in-office bleaching with 27% hydrogen peroxide (in the same trays). The efficacy of tooth whitening was assessed by determining the color change associated with the six upper anterior teeth using a value-ordered shade guide. Sensitivity was self-assessed with the use of a visual analog scale (VAS). Tooth shade and sensitivity were assessed at the following points: pretreatment; immediately after the home whitening phase; immediately after the in-office phase (groups B and C); and one week post active treatment. At the one week follow-up visit, subjects in group A had a mean (SD) color change of 5.9 (1.83) (teeth were lighter) immediately after cessation of treatment (p<0.01). Subjects in groups B and C experienced a greater change in mean (SD) shade immediately following their respective in-office treatments of 5.1 (1.53) and 5.4 (1.55). However, within one week, the shade of these teeth regressed to a similar degree to that achieved by subjects treated in group A. Overall, no significant difference in shade change or sensitivity was produced between the three groups. Investigators concluded that the in-office element of combined whitening produced no significant difference in tooth color or sensitivity when compared with home whitening alone.


Assuntos
Consultórios Odontológicos , Sensibilidade da Dentina/etiologia , Autocuidado , Clareamento Dental/métodos , Adulto , Peróxido de Carbamida , Cor , Dente Canino/patologia , Sensibilidade da Dentina/classificação , Seguimentos , Humanos , Peróxido de Hidrogênio/administração & dosagem , Peróxido de Hidrogênio/uso terapêutico , Incisivo/patologia , Pessoa de Meia-Idade , Medição da Dor , Peróxidos/administração & dosagem , Peróxidos/uso terapêutico , Fatores de Tempo , Clareamento Dental/instrumentação , Clareadores Dentários/administração & dosagem , Clareadores Dentários/uso terapêutico , Resultado do Tratamento , Ureia/administração & dosagem , Ureia/análogos & derivados , Ureia/uso terapêutico , Adulto Jovem
19.
Poult Sci ; 90(12): 2874-8, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22080028

RESUMO

Escherichia coli and Salmonella spp. are ubiquitous in the poultry production environment, and hence, their transmission to poultry products is of concern. Industry has widely used freezing as a strategy to halt pathogen growth, and more recently, crust freezing has been suggested as a means to improve mechanical operations, quality, and safety of poultry products. The purpose of this study was to evaluate the effect of crust freezing on the survival of Escherichia coli and Salmonella Typhimurium that were artificially inoculated on the surface of raw poultry products with or without adhering skin. Ampicillin-resistant (AR) E. coli JM 109 and nalidixic acid-resistant (NAR) Salmonella Typhimurium were used in the experiments. A set of cultures was subjected to cold-shock stress by storage at 4°C for 10 d. After being either cold-shocked or non-cold-shocked, commercial chicken breasts without skin and chicken thighs with skin were inoculated in separate experiments with each bacterium. Samples were crust frozen at -85°C for 20 min or completely frozen at -85°C for 60 min. The E. coli and Salmonella Typhimurium were recovered on appropriate selective and nonselective media containing the corresponding antibiotic. Log reductions and extent of injury were calculated and treatments were compared using ANOVA. No significant differences were observed in the reduction of cold-shocked or non-cold-shocked bacteria on products with or without skin that were crust or completely frozen. The average reduction for E. coli was 0.15 log(10) cfu/mL of rinse, and for Salmonella Typhimurium 0.10 log(10) cfu/mL of rinse; therefore, none of the final reductions were greater than the desired target (1 log). Bacterial cell injury was not significantly different (P > 0.05) among any of the treatments. Data showed no practical significance for initial reduction of these pathogens from crust freezing and thus, this technology should not be considered as a strategy for the reduction of E. coli and Salmonella Typhimurium on poultry.


Assuntos
Escherichia coli/fisiologia , Conservação de Alimentos/métodos , Congelamento , Carne/microbiologia , Salmonella typhimurium/fisiologia , Animais , Galinhas
20.
Poult Sci ; 90(10): 2348-54, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21934019

RESUMO

The objective of the present study was to compare carnosine levels in tissues of broilers under stress conditions with those of broilers under nonstress conditions. Blood heterophil:lymphocyte ratio and corticosterone levels were measured as indicators of the level of stress. Corticosterone levels of stressed broilers (24,358.67 pg/mL) were 10-fold higher (P = 0.002) than those of nonstressed broilers (2,275.46 pg/mL). However, no difference (P = 0.29) was found in heterophil:lymphocyte ratio of nonstressed (0.29) and stressed (0.31) birds. Carnosine content in breast of stressed birds (17.39 mg/g) was 10 times higher (P = 0.005) than that of nonstressed birds (1.85 mg/g). Carnosine content in thigh of stressed birds (21.25 mg/g) was approximately 2-fold higher (P = 0.001) than that of nonstressed birds (11.10 mg/g). Carnosine content in brain of stressed birds did not differ (P = 0.82) from that of nonstressed birds. Based on the present study, muscle carnosine recovery levels increase during short-term stress, whereas levels in the brain are not affected.


Assuntos
Química Encefálica , Carnosina/análise , Galinhas , Músculo Esquelético/química , Doenças das Aves Domésticas/metabolismo , Estresse Psicológico/metabolismo , Animais , Corticosterona/sangue , Manobra Psicológica , Contagem de Linfócitos , Masculino
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