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1.
Pediatr Cardiol ; 44(3): 540-548, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36422652

RESUMO

Over the past 2 decades, fundamentals of exercise medicine, including clinical exercise testing, assessment and promotion of physical activity, exercise prescription, and supervised exercise training/rehabilitation programming have demonstrated considerable clinical value in the management of children and adolescents with congenital and acquired heart disease. Although the principles of exercise medicine have become an integral component in pediatric cardiology, there are no standardized training recommendations for exercise physiology during pediatric cardiology fellowship at this time. Thus, the Pediatric Cardiology Exercise Medicine Curriculum Committee (PCEMCC) was formed to establish core and advanced exercise physiology training recommendations for pediatric cardiology trainees. The PCEMCC includes a diverse group of pediatric cardiologists, exercise physiologists, and fellowship program directors. The expert consensus training recommendations are by no means a mandate and are summarized herein, including suggestions for achieving the minimum knowledge and training needed for general pediatric cardiology practice.


Assuntos
Cardiologia , Cardiopatias , Criança , Humanos , Adolescente , Bolsas de Estudo , Cardiologia/educação , Currículo , Exercício Físico
2.
Occup Med (Lond) ; 73(3): 138-141, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-36719101

RESUMO

BACKGROUND: Monitoring trends in the burden of illness and injury attributable to work is key in assessing occupational health hazards; however, New Brunswick does not participate in the Canadian National Ambulatory Care Reporting System which itself does not collect details of occupation and industry. AIMS: We set out to determine the proportion of emergency department attendances that were attributable to a work-related cause. We also wanted to evaluate the recording of occupation in the electronic health record system, and to describe the characteristics of patients with a work-related presentation. METHODS: A retrospective observational study over a 1-year period was conducted using an administrative database obtained from Canadian Emergency Department Information System. Descriptive statistics are used to present the analysis of categorical and continuous data. RESULTS: A total of 49 365 patients were included for analysis. Two per cent of patients presented with a self-reported work-related condition. Health care and social assistance, construction, retail trade and manufacturing were the most common industries reported by patients. CONCLUSIONS: This study found the rate of work-related medical conditions to be substantially less than expected, and that occupation was not captured for any patients presenting to the emergency department with a work-related condition, despite a field being available in the electronic health record registration system. We were able to analyse the industry sectors for work-related presentations. The recording and coding of occupation and industry would significantly benefit occupational epidemiology in emergency medicine as well as potentially improving patient outcomes and health system efficiencies.


Assuntos
Traumatismos Ocupacionais , Humanos , Canadá/epidemiologia , Traumatismos Ocupacionais/epidemiologia , Serviço Hospitalar de Emergência , Ocupações , Indústrias
3.
World J Surg ; 42(5): 1432-1439, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29484475

RESUMO

INTRODUCTION: Medullary thyroid cancer (MTC) is a rare tumour of neuroendocrine origin with a more aggressive profile than differentiated thyroid cancer. Familial cases of MTC are associated with RET mutations whilst RAS mutations appear to be a frequent finding in RET negative tumours. The aims of this study were to analyse survival outcomes in MTC and to evaluate the role of RAS immunohistochemistry in the identification of sporadic disease. MATERIALS AND METHODS: A retrospective cohort study of consecutive patients with MTC was undertaken. The primary outcome measures were overall survival and disease-free survival. Survival analysis was performed on the basis of sporadic and familial disease. Patients had routine RET testing using the capillary (Sanger) sequencing method. Histopathological MTC slides from 100 patients were tested for HRASQ61R, a common somatic RAS mutation in MTC, with mutation-specific immunohistochemistry (IHC). RESULTS: A total of 195 patients had surgical treatment of MTC in the period 1980 to 2016. There were 83 males and 112 females with a mean age of 53.0 years. A total of 39 (20%) patients had familial disease. Sporadic cases had a higher median pre-op calcitonin (969.5 vs. 257.5 pg/ml), greater mean primary tumour size (23.5 vs. 12.5 mm) and more distant metastases (12.8 vs. 10.3%). Multivariate analysis showed age (p = 0.005), Multiple Endocrine Neoplasia Type 2 (MEN2) status (p = 0.021) and distant metastasis (p = 0.002) to be significant independent predictors of survival. Significant independent predictors for disease-free survival were age (p = 0.015), MEN2 (p = 0.002), pre-op calcitonin (p = 0.033) and venous invasion (p = 0.001). The overall 5-year survival was 100% for familial MTC and 78% for sporadic MTC. The 10-year disease-free survival was 94% for familial MTC and 61% for sporadic cases. A total of 100 cases of MTC underwent mutation-specific IHC for HRASQ61R. Of these, 18 had confirmed MEN2. IHC had 100% specificity in excluding MEN2. Twelve (12%) of 100 patients stained positive for HRASQ61R mutation. CONCLUSION: In the era of genetic testing, RET status significantly influences disease-specific survival in MTC. Mutation-specific IHC for HRASQ61R may have a role in the identification of patients presenting with sporadic disease.


Assuntos
Carcinoma Neuroendócrino/genética , Carcinoma Neuroendócrino/mortalidade , Mutação , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/mortalidade , Proteínas ras/genética , Fatores Etários , Calcitonina/análise , Carcinoma Neuroendócrino/cirurgia , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasia Endócrina Múltipla Tipo 2a/patologia , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/cirurgia
4.
J Evol Biol ; 30(10): 1810-1820, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28590579

RESUMO

Gene flow is expected to limit adaptive divergence, but the ecological and behavioural factors that govern gene flow are still poorly understood, particularly at the earliest stages of population divergence. Reduced gene flow through mate choice (sexual isolation) can evolve even under conditions of subtle population divergence if intermediate phenotypes have reduced fitness. We indirectly tested the hypothesis that mate choice has evolved between coexisting littoral and pelagic ecotypes of polyphenic pumpkinseed sunfish (Lepomis gibbosus) that have diverged in morphology and resource use and where intermediate phenotypes have reduced performance. We assessed the ecotype of nesting males and females using stable isotope estimates of diet and a divergent male morphological trait, oral jaw width. We found positive assortative mating between ecotypes in a common spawning habitat along exposed lake shorelines, but contrary to expectations, assortative mating was variably expressed between two sampling years. Although the factors that influence variable assortative mating remain unclear, our results are consistent with mate choice being expressed by ecotypes. Despite being variably expressed, mate choice will reduce gene flow between ecotypes and could contribute to further adaptive divergence depending on its frequency and strength in the population. Our findings add to a growing body of evidence indicating mate choice behaviour can be a plastic trait, an idea that should be more explicitly considered in empirical studies of mate choice as well as conceptual frameworks of mate choice evolution and adaptive divergence.


Assuntos
Ecótipo , Perciformes/fisiologia , Comportamento Sexual Animal/fisiologia , Adaptação Fisiológica/genética , Animais , Feminino , Fluxo Gênico , Especiação Genética , Masculino , Perciformes/genética
5.
World J Urol ; 35(6): 943-949, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27730305

RESUMO

PURPOSE: This study aims to determine the significance of androgen receptor (AR) expression in urothelial carcinoma of the upper urinary tract (UTUC). METHODS: AR expression was assessed on tissue microarrays containing specimens of 737 patients with UTUC who underwent radical nephroureterectomy with curative intent. AR expression was correlated with clinical and pathological tumor features as well as recurrence-free survival (RFS), cancer-specific survival (CSS) and overall survival (OS). RESULTS: Overall, AR was expressed in 11 % of tumors. AR expression was significantly associated with tumor necrosis as well as sessile and multifocal tumor growth but not with RFS, CSS or OS. AR was detected nearly twice as often in tumors of the ureter than of the pelvicalyceal system (p = 0.005). Subgroup analyses showed that the significant associations of AR with unfavorable pathologic features were exclusively attributable to tumors located in the ureter. However, in both ureteral and pelvicalyceal tumors, AR status was independent of RFS, CSS and OS. CONCLUSIONS: In this cohort of patients treated with RNU, AR expression was found in approximately 10 % of UTUCs, twice as often in ureteral than in pelvicalyceal tumors. While AR expression had no impact on postoperative prognosis, it was significantly associated with unfavorable pathologic features in ureteral tumors. Steroid hormone signaling might be relevant for future investigations of differences between ureteral and pelvicalyceal tumors.


Assuntos
Carcinoma de Células de Transição/patologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais/patologia , Receptores Androgênicos/genética , Neoplasias Ureterais/patologia , Adulto , Idoso , Carcinoma de Células de Transição/metabolismo , Carcinoma de Células de Transição/mortalidade , Carcinoma de Células de Transição/cirurgia , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Renais/metabolismo , Neoplasias Renais/mortalidade , Neoplasias Renais/cirurgia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Nefrectomia/métodos , Nefrectomia/mortalidade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Análise de Sobrevida , Neoplasias Ureterais/metabolismo , Neoplasias Ureterais/mortalidade , Neoplasias Ureterais/cirurgia
6.
N Engl J Med ; 369(25): 2391-2405, 2013 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-24325359

RESUMO

BACKGROUND: Somatic mutations in the Janus kinase 2 gene (JAK2) occur in many myeloproliferative neoplasms, but the molecular pathogenesis of myeloproliferative neoplasms with nonmutated JAK2 is obscure, and the diagnosis of these neoplasms remains a challenge. METHODS: We performed exome sequencing of samples obtained from 151 patients with myeloproliferative neoplasms. The mutation status of the gene encoding calreticulin (CALR) was assessed in an additional 1345 hematologic cancers, 1517 other cancers, and 550 controls. We established phylogenetic trees using hematopoietic colonies. We assessed calreticulin subcellular localization using immunofluorescence and flow cytometry. RESULTS: Exome sequencing identified 1498 mutations in 151 patients, with medians of 6.5, 6.5, and 13.0 mutations per patient in samples of polycythemia vera, essential thrombocythemia, and myelofibrosis, respectively. Somatic CALR mutations were found in 70 to 84% of samples of myeloproliferative neoplasms with nonmutated JAK2, in 8% of myelodysplasia samples, in occasional samples of other myeloid cancers, and in none of the other cancers. A total of 148 CALR mutations were identified with 19 distinct variants. Mutations were located in exon 9 and generated a +1 base-pair frameshift, which would result in a mutant protein with a novel C-terminal. Mutant calreticulin was observed in the endoplasmic reticulum without increased cell-surface or Golgi accumulation. Patients with myeloproliferative neoplasms carrying CALR mutations presented with higher platelet counts and lower hemoglobin levels than patients with mutated JAK2. Mutation of CALR was detected in hematopoietic stem and progenitor cells. Clonal analyses showed CALR mutations in the earliest phylogenetic node, a finding consistent with its role as an initiating mutation in some patients. CONCLUSIONS: Somatic mutations in the endoplasmic reticulum chaperone CALR were found in a majority of patients with myeloproliferative neoplasms with nonmutated JAK2. (Funded by the Kay Kendall Leukaemia Fund and others.).


Assuntos
Calreticulina/genética , Mutação , Síndromes Mielodisplásicas/genética , Mielofibrose Primária/genética , Trombocitemia Essencial/genética , Sequência de Aminoácidos , Doenças da Medula Óssea/genética , Calreticulina/análise , Éxons , Humanos , Janus Quinase 2/genética , Leucemia Mieloide/genética , Dados de Sequência Molecular , Neoplasias/genética , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
7.
Osteoarthritis Cartilage ; 24(6): 949-61, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26778530

RESUMO

OBJECTIVE: Cam hip shape morphology is a recognised cause of femoroacetabular impingement (FAI) and is associated with hip osteoarthritis. Our aim was to systematically review the available epidemiological evidence assessing the prevalence of cam hip shape morphology in the general population and any studied subgroups including subjects with and without hip pain. DESIGN: All studies that reported the prevalence of cam morphology, measured by alpha angles, in subjects aged 18 and over, irrespective of study population or presence of hip symptoms were considered for inclusion. We searched AMED, MEDLINE, EMBASE, CINAHL and CENTRAL in October 2015. Two authors independently identified eligible studies and assessed risk of bias. We planned to pool data of studies considered clinically homogenous. RESULTS: Thirty studies met inclusion criteria. None of the included studies were truly population-based: three included non-representative subgroups of the general population, 19 included differing clinical populations, while eight included professional athletes. All studies were judged to be at high risk of bias. Due to substantial clinical heterogeneity meta analysis was not possible. Across all studies, the prevalence estimates of cam morphology ranged from 5 to 75% of participants affected. We were unable to demonstrate a higher prevalence in selected subgroups such as athletes or those with hip pain. CONCLUSIONS: There is currently insufficient high quality data to determine the true prevalence of cam morphology in the general population or selected subgroups. Well-designed population-based epidemiological studies that use homogenous case definitions are required to determine the prevalence of cam morphology and its relationship to hip pain.


Assuntos
Articulação do Quadril , Impacto Femoroacetabular , Humanos , Osteoartrite do Quadril , Dor , Prevalência
8.
Epidemiol Infect ; 144(2): 274-84, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26264893

RESUMO

Cryptosporidium, a parasite known to cause large drinking and recreational water outbreaks, is tolerant of chlorine concentrations used for drinking water treatment. Human laboratory-based surveillance for enteric pathogens detected a cryptosporidiosis outbreak in Baker City, Oregon during July 2013 associated with municipal drinking water. Objectives of the investigation were to confirm the outbreak source and assess outbreak extent. The watershed was inspected and city water was tested for contamination. To determine the community attack rate, a standardized questionnaire was administered to randomly sampled households. Weighted attack rates and confidence intervals (CIs) were calculated. Water samples tested positive for Cryptosporidium species; a Cryptosporidium parvum subtype common in cattle was detected in human stool specimens. Cattle were observed grazing along watershed borders; cattle faeces were observed within watershed barriers. The city water treatment facility chlorinated, but did not filter, water. The community attack rate was 28·3% (95% CI 22·1-33·6), sickening an estimated 2780 persons. Watershed contamination by cattle probably caused this outbreak; water treatments effective against Cryptosporidium were not in place. This outbreak highlights vulnerability of drinking water systems to pathogen contamination and underscores the need for communities to invest in system improvements to maintain multiple barriers to drinking water contamination.


Assuntos
Criptosporidiose/epidemiologia , Cryptosporidium/fisiologia , Diarreia/epidemiologia , Surtos de Doenças , Água Potável/parasitologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Criptosporidiose/parasitologia , Criptosporidiose/prevenção & controle , Diarreia/parasitologia , Diarreia/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oregon/epidemiologia , Inquéritos e Questionários , Adulto Jovem
9.
World J Surg ; 40(7): 1618-24, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27138882

RESUMO

BACKGROUND: The BRAF (V600E) mutation is a recognised molecular marker in papillary thyroid cancer (PTC), reported incidence from 30 to 80 %. BRAF(V600E) aberrantly activates the MAPK pathway, a central regulator of cell growth and proliferation. Previous studies have reported conflicting data regarding the impact of BRAF(V600E) on clinicopathological features of PTC. The study aims to determine whether BRAF(V600E) is useful as a prognostic biomarker in PTC. METHODS: A cohort study of patients undergoing surgery for PTC was undertaken. The primary outcome measure was disease-free survival. Secondary outcome measures were tumour size, nodal positivity and radioactive iodine ablation rate. All cases were re-examined to confirm PTC. Immunohistochemistry for BRAF(V600E) was performed on tissue microarrays. A single endocrine pathologist, blinded to clinicopathological data, interpreted staining. RESULTS: 496 patients with PTC were included, and 309 (62 %) were BRAF(V600E) positive. Tumour size was similar for BRAF(V600E)-positive and -negative tumours (21.3 vs. 23.2 mm, p = 0.23). BRAF(V600E)-positive patients were significantly older at first operation (mean age 45 versus 49 years, p = 0.003). BRAF(V600E)-positive PTCs had a higher rate of disease recurrence (12.9 vs. 5.6 %, p = 0.004), lymph node metastasis (44 vs. 29.4 %, p = 0.004) and extra-thyroidal extension (44 vs. 22 %, p < 0.001). Five-year disease-free survival was 89.6 % for BRAF(V600E) positive and 96.3 % for negative tumours, p < 0.001. There was no difference between groups for vascular invasion or multifocality. The mean follow-up was 57 months for both groups. CONCLUSION: BRAF(V600E) in PTC predicts an increased risk of lymph node metastasis, extra-thyroidal extension and reduced disease-free survival. It is an additional useful prognostic biomarker.


Assuntos
Carcinoma/genética , Carcinoma/secundário , Recidiva Local de Neoplasia/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Técnicas de Ablação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Carcinoma/cirurgia , Carcinoma Papilar , Criança , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Humanos , Radioisótopos do Iodo/uso terapêutico , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Proto-Oncogênicas B-raf/análise , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/cirurgia , Carga Tumoral/genética , Adulto Jovem
10.
J Environ Qual ; 45(6): 1960-1969, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27898779

RESUMO

Land application of biosolids to low-fertility soil can improve soil quality by increasing concentrations of macronutrients and trace elements. Mixing biosolids with sawdust could reduce the risks of contaminant accumulation posed by rebuilding soils using biosolids alone. We aimed to determine the effects of biosolids and biosolids-sawdust on the plant quality and chemical composition of sorghum, rapeseed, and ryegrass. Plants were grown in a greenhouse over a 5-mo period in a low-fertility soil amended with biosolids (1250 kg N ha), biosolids-sawdust (0.5:1), or urea (200 kg N ha). Biosolids application increased the biomass of sorghum, rapeseed, and ryegrass up to 14.0, 11.9, and 4.1 t ha eq, respectively. Mixing sawdust with biosolids resulted in a growth response similar to biosolids treatments in rapeseed but nullified the effect of biosolids in sorghum. Urea fertilization provided insufficient nutrients to promote rapeseed growth and seed production, whereas seed yields after biosolids application were 2.5 t ha. Biosolids and biosolids-sawdust application enhanced plant quality by increasing element concentrations, especially Zn, and potentially toxic elements (Cd, Cr, Ni) did not exceed food safety standards. An application of 50 t ha of biosolids, equivalent to 1250 kg N ha, did not exceed current soil limits of Cu, Zn, and Cd and hence was effective in rebuilding soil without accumulating contaminants. The effect of mixing sawdust with biosolids varies with plant species but can further enhance plant nutrient quality in biomass and seeds, especially P, Cu, Zn, Mn, Fe, S, and Na.


Assuntos
Produtos Agrícolas , Metais Pesados , Poluentes do Solo , Biomassa , Solo
11.
J Environ Qual ; 45(6): 1970-1978, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27898783

RESUMO

Increasing production of biowastes, particularly biosolids (sewage sludge), requires sustainable management strategies for their disposal. Biosolids can contain high concentrations of nutrients; hence, land application can have positive effects on plant growth and soil fertility, especially when applied to degraded soils. However, high rates of biosolids application may result in excessive nitrogen (N) leaching, which can be mitigated by blending biosolids with other biowastes, such as sawdust. We aimed to determine the effects of biosolids and sawdust on growth and N uptake by sorghum, rapeseed, and ryegrass as well as N losses via leaching. Plants were grown in a greenhouse over a 5-mo period in a low-fertility soil amended with biosolids (1250 kg N ha), biosolids-sawdust (0.5:1), or urea (200 kg N ha). Urea application increased biomass production of sorghum and ryegrass but proved insufficient for rapeseed on low-fertility soil. Biosolids application increased plant N concentrations in ryegrass and rapeseed and increased N uptake into the seeds of sorghum, increasing seed quality. Biosolids application did result in lower N leaching compared with urea, irrespective of plant species, and N leaching was unaffected by mixing the biosolids with sawdust. There was an indication of biological nitrification inhibition in the rhizosphere of sorghum. Rapeseed had similar growth and N uptake into biomass in biosolids and biosolids-sawdust treatments and hence was the most promising species with regard to recycling fresh sawdust in combination with high rates of biosolids on low-fertility soil.


Assuntos
Produtos Agrícolas , Esgotos , Poluentes do Solo , Biomassa , Nitrogênio , Solo
12.
Public Health ; 139: 183-188, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27207724

RESUMO

OBJECTIVES: The US Chemical Safety Board (CSB), a federal agency that investigates significant chemical incidents and hazards, is interested in determining the impact of the recommendations resulting from its investigations, and how to better more effective recommendations to prevent chemical incidents. STUDY DESIGN: This is a descriptive study of the US Chemical Safety Board's safety recommendations. METHODS: The CSB coded and analysed its safety recommendations according to potential impact on reducing incidents, implementation status, purpose and recipient type. RESULTS: As of March 31, 2015, the CSB has issued 733 recommendations, 75% (548) of which are closed and 25% (185) of which remain open. For recommendations categorised as having high, medium, and low impact, 38% (78), 76% (160), and 78% (245) were implemented, respectively. CONCLUSIONS: CSB recommendations have led to important and lasting safety changes through regulations, industry guidance and voluntary consensus standards, and individual companies; however, coding recommendations by potential impact do not fully capture the influence of CSB recommendations. While this methodology serves as a preliminary way to determine the effect of recommendations, further data are needed to determine the extent to which these safety changes have reduced the frequency or severity of industrial accidents.


Assuntos
Acidentes de Trabalho/prevenção & controle , Vazamento de Resíduos Químicos/prevenção & controle , Indústria Química , Segurança Química , Órgãos Governamentais/organização & administração , Acidentes de Trabalho/estatística & dados numéricos , Vazamento de Resíduos Químicos/estatística & dados numéricos , Saúde Ambiental , Conselho Diretor , Humanos , Saúde Ocupacional , Estados Unidos
13.
Nano Lett ; 15(7): 4348-55, 2015 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-26086785

RESUMO

The monolithic integration of InAs(1-x)Sb(x) semiconductor nanowires on graphitic substrates holds enormous promise for cost-effective, high-performance, and flexible devices in optoelectronics and high-speed electronics. However, the growth of InAs(1-x)Sb(x) nanowires with high aspect ratio essential for device applications is extremely challenging due to Sb-induced suppression of axial growth and enhancement in radial growth. We report the realization of high quality, vertically aligned, nontapered and ultrahigh aspect ratio InAs(1-x)Sb(x) nanowires with Sb composition (xSb(%)) up to ∼12% grown by indium-droplet assisted molecular beam epitaxy on graphite substrate. Low temperature photoluminescence measurements show that the InAs(1-x)Sb(x) nanowires exhibit bright band-to-band related emission with a distinct redshift as a function of Sb composition providing further confirmation of successful Sb incorporation in as-grown nanowires. This study reveals that the graphite substrate is a more favorable platform for InAs(1-x)Sb(x) nanowires that could lead to hybrid heterostructures possessing potential device applications in optoelectronics.

14.
Br J Cancer ; 112(6): 963-70, 2015 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-25742472

RESUMO

BACKGROUND: Mutations affecting RAS genes are now established predictive markers of nonresponse to anti-EGFR antibodies in advanced CRC. This analysis assessed the prognostic and predictive impact of extended RAS and PIK3CA gene mutation status in patients receiving capecitabine plus or minus bevacizumab (±mitomycin C) in the randomised phase III MAX study. METHODS: DNA was extracted from archival macrodissected formalin-fixed paraffin-embedded tumour tissue. Mutation status was determined using pyrosequencing, confirmed with Sanger sequencing (for equivocal RAS) and correlated with efficacy outcomes. Predictive analyses were undertaken using a test for interaction involving both C vs CB+CBM. RESULTS: Of the available 280 of the 471 (59.4%) patients, mutations in KRAS exons 2, 3 and 4 and NRAS 2, 3 and 4 were as follows: 32%, 2.9%, 2.2%, 1.4%, 0.7% and 0% (total RAS MT 39%). The PIK3CA MT rate was 7.5% exon 9 and 3.6% exon 20. Extended RAS gene mutation status (WT vs MT) had no prognostic impact for PFS (HR 0.91 (0.71-1.17)) or OS (HR 0.95 (0.71-1.25)). The RAS gene mutation status was not predictive of the effectiveness of bevacizumab for PFS (HR 0.56 (0.37-0.85) for RAS MT and HR 0.69 (0.5-0.97) for RAS WT; P for interaction 0.50). The PIK3CA mutation was neither predictive for bevacizumab effect nor prognostic. CONCLUSION: Of KRAS exon 2 WT patients, 10% had additional RAS mutations. Neither all RAS gene mutation status nor PIK3CA mutation status was prognostic for PFS or OS, or predictive of bevacizumab outcome in patients with advanced CRC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Genes ras , Mutação , Fosfatidilinositol 3-Quinases/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/administração & dosagem , Bevacizumab , Capecitabina , Classe I de Fosfatidilinositol 3-Quinases , Neoplasias Colorretais/patologia , DNA de Neoplasias/química , DNA de Neoplasias/genética , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/análogos & derivados , Humanos , Masculino , Mitomicina/administração & dosagem , Prognóstico
15.
Ann Oncol ; 26(12): 2483-90, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26386124

RESUMO

BACKGROUND: Data from murine models suggest that CD40 activation may synergize with cytotoxic chemotherapy. We aimed to determine the maximum tolerated dose (MTD) and toxicity profile and to explore immunological biomarkers of the CD40-activating antibody CP-870,893 with cisplatin and pemetrexed in patients with malignant pleural mesothelioma (MPM). PATIENTS AND METHODS: Eligible patients had confirmed MPM, ECOG performance status 0-1, and measurable disease. Patients received cisplatin 75 mg/m(2) and pemetrexed 500 mg/m(2) on day 1 and CP-870,893 on day 8 of a 21-day cycle for maximum 6 cycles with up to 6 subsequent cycles single-agent CP-870,893. Immune cell subset changes were examined weekly by flow cytometry. RESULTS: Fifteen patients were treated at three dose levels. The MTD of CP-870,893 was 0.15 mg/kg, and was exceeded at 0.2 mg/kg with one grade 4 splenic infarction and one grade 3 confusion and hyponatraemia. Cytokine release syndrome (CRS) occurred in most patients (80%) following CP-870,893. Haematological toxicities were consistent with cisplatin and pemetrexed chemotherapy. Six partial responses (40%) and 9 stable disease (53%) as best response were observed. The median overall survival was 16.5 months; the median progression-free survival was 6.3 months. Three patients survived beyond 30 months. CD19+ B cells decreased over 6 cycles of chemoimmunotherapy (P < 0.001) with a concomitant increase in the proportion of CD27+ memory B cells (P < 0.001) and activated CD86+CD27+ memory B cells (P < 0.001), as an immunopharmacodynamic marker of CD40 activation. CONCLUSIONS: CP-870,893 with cisplatin and pemetrexed is safe and tolerable at 0.15 mg/kg, although most patients experience CRS. While objective response rates are similar to chemotherapy alone, three patients achieved long-term survival. AUSTRALIA NEW ZEALAND CLINICAL TRIALS REGISTRY NUMBER: ACTRN12609000294257.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Antígenos CD40/metabolismo , Cisplatino/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Mesotelioma/tratamento farmacológico , Pemetrexede/administração & dosagem , Neoplasias Pleurais/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais Humanizados , Antígenos CD40/agonistas , Estudos de Coortes , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Masculino , Mesotelioma/diagnóstico , Mesotelioma/metabolismo , Mesotelioma Maligno , Pessoa de Meia-Idade , Neoplasias Pleurais/diagnóstico , Neoplasias Pleurais/metabolismo , Estudos Prospectivos
16.
Nanotechnology ; 25(16): 165704, 2014 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-24675237

RESUMO

For the first time, new epitaxial graphene nano-structures resembling charged 'bubbles' and 'domes' are reported. A strong influence, arising from the change in morphology, on the graphene layer's electronic, mechanical and optical properties has been shown. The morphological properties of these structures have been studied with atomic force microscopy (AFM), ultrasonic force microscopy (UFM) and Raman spectroscopy. After initial optical microscopy observation of the graphene, a detailed description of the surface morphology, via AFM and nanomechanical UFM measurements, was obtained. Here, graphene nano-structures, domes and bubbles, ranging from a few tens of nanometres (150­200 nm) to a few µm in size have been identified. The AFM topographical and UFM stiffness data implied the freestanding nature of the graphene layer within the domes and bubbles, with heights on the order of 5­12 nm. Raman spectroscopy mappings of G and 2D bands and their ratio confirm not only the graphene composition of these structures but also the existence of step bunching, defect variations and the carrier density distribution. In particular, inside the bubbles and substrate there arises complex charge redistribution; in fact, the graphene bubble­substrate interface forms a charged capacitance. We have determined the strength of the electric field inside the bubble­substrate interface, which may lead to a minigap of the order of 5 meV opening for epitaxial graphene grown on 4H-SiC face-terminated carbon.

17.
Int Urogynecol J ; 25(5): 631-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24337585

RESUMO

INTRODUCTION AND HYPOTHESIS: Shortened perineal body (PB) is associated with an increased risk of ultrasound-detected obstetric anal sphincter tear. The objective was to determine if shortened perineal body length (<3 cm) is a risk factor for ultrasound-detected anal sphincter tear at first delivery. METHODS: Pregnant nulliparous women were recruited over 18 months. At 35-37 weeks' gestation and 6 weeks' postpartum perineal body length (PB) was measured and subjects completed quality of life questionnaires. Primary outcome was ultrasound-diagnosed anal sphincter tear at 6 weeks postpartum. Secondary outcomes were also assessed. A priori power analysis determined that 70 subjects were needed to detect a difference in anal sphincter tear based on a PB cut-off of 3 cm. RESULTS: Seventy-three subjects completed the study. Mode of delivery was 69.9% spontaneous vaginal, 15.1% operative vaginal, and 15.1% labored cesarean. There were 25 anal sphincter abnormalities (34.2%) seen on ultrasound: 11 (15.1%) internal or external sphincter tears, 3 (4.1%) internal sphincter atrophy, 6 (8.2%) external sphincter thinning, and 7 (9.6%) external sphincter scarring. Only the 11 sphincter tears qualified as abnormal for the primary outcome. In the vaginal delivery group 16.4% (10 out of 61) had a sphincter tear, compared with 8.3% (1 out of 12) in the labored cesarean group (p = 0.68). Women with PB < 3 had a significantly higher rate of ultrasound-diagnosed anal sphincter tear (40.0% vs 11.1%, p = 0.038). When comparing women with and without sphincter tear, there was a significant difference in mean antepartum PB (3.1 vs 3.7 cm, p = 0.043). CONCLUSIONS: A shortened perineal body length in primiparous women is associated with an increased risk of anal sphincter tear at the time of first delivery.


Assuntos
Canal Anal/lesões , Lacerações/etiologia , Complicações do Trabalho de Parto/etiologia , Períneo/anatomia & histologia , Períneo/diagnóstico por imagem , Adulto , Feminino , Humanos , Paridade , Gravidez , Estudos Prospectivos , Fatores de Risco , Ultrassonografia
18.
J Periodontal Res ; 48(6): 713-21, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23441958

RESUMO

BACKGROUND AND OBJECTIVE: Gingival keratinocytes are used in model systems to investigate the interaction between periodontal bacteria and the epithelium in the initial stages of the periodontal disease process. Primary gingival epithelial cells (GECs) have a finite lifespan in culture before they enter senescence and cease to replicate, while epithelial cells immortalized with viral proteins can exhibit chromosomal rearrangements. The aim of this study was to generate a telomerase immortalized human gingival epithelial cell line and compare its in vitro behaviour to that of human GECs. MATERIAL AND METHODS: Human primary GECs were immortalized with a bmi1/hTERT combination to prevent cell cycle triggers of senescence and telomere shortening. The resultant cell-line, telomerase immortalized gingival keratinocytes (TIGKs), were compared to GECs for cell morphology, karyotype, growth and cytokeratin expression, and further characterized for replicative lifespan, expression of toll-like receptors and invasion by P. gingivalis. RESULTS: TIGKs showed morphologies, karyotype, proliferation rates and expression of characteristic cytokeratin proteins comparable to GECs. TIGKs underwent 36 passages without signs of senescence and expressed transcripts for toll-like receptors 1-6, 8 and 9. A subpopulation of cells underwent stratification after extended time in culture. The cytokeratin profiles of TIGK monolayers were consistent with basal cells. When allowed to stratify, cytokeratin profiles of TIGKs were consistent with suprabasal cells of the junctional epithelium. Further, TIGKs were comparable to GECs in previously reported levels and kinetics of invasion by wild-type P. gingivalis and an invasion defective ΔserB mutant. CONCLUSION: Results confirm bmi1/hTERT immortalization of primary GECs generated a robust cell line with similar characteristics to the parental cell type. TIGKs represent a valuable model system for the study of oral bacteria interactions with host gingival cells.


Assuntos
Gengiva/citologia , Adulto , Contagem de Células , Técnicas de Cultura de Células , Linhagem Celular Transformada , Proliferação de Células , Forma Celular/fisiologia , Senescência Celular/fisiologia , Inserção Epitelial/citologia , Células Epiteliais/citologia , Células Epiteliais/microbiologia , Gengiva/microbiologia , Humanos , Cariótipo , Queratina-13/metabolismo , Queratina-14/metabolismo , Queratina-19/metabolismo , Microscopia Confocal , Microscopia de Fluorescência , Complexo Repressor Polycomb 1/genética , Porphyromonas gingivalis/fisiologia , Retroviridae/genética , Telomerase/genética , Telômero/fisiologia , Receptores Toll-Like/metabolismo , Transdução Genética , Dedos de Zinco/genética
19.
J Nanosci Nanotechnol ; 13(1): 467-76, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23646756

RESUMO

Self-assembled nanostructures of CulnGaSe2 (CIGS) comprising of nanosheets with sheet thickness of 20 nm have been developed via one-step electrochemically alloying technique. These self-assembled nanoplates exhibit highly intersecting behavior and transform from CuSe to CIGS as the reduction potential was varied. The morphological analysis indicated that the process resulted in a progression of crystallites to a series of heavy dense intersecting nanoplates. Further analyses revealed that the nanostructures keep their integrity on heat treatment. The structure confirms the inclusion of Indium and Gallium at higher reduction potentials and its transition from pseudoamorphous to polycrystalline structure. A strong correlation between reduction potential, and the composition was established. The spectroscopic and optical spectra clearly prove that the direct band gap for the as-grown and annealed thin films, and appropriate for solar cell applications. These self-assembled dense interweaved nanoplates structure have not been observed previously in CIGS semiconductor system and have potential implications forenergy applications.


Assuntos
Cobre/química , Cristalização/métodos , Membranas Artificiais , Nanoestruturas/química , Cobre/efeitos da radiação , Campos Eletromagnéticos , Luz , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Propriedades de Superfície
20.
Nat Genet ; 32(4): 676-80, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12434154

RESUMO

We report here the identification of a gene associated with the hyperparathyroidism-jaw tumor (HPT-JT) syndrome. A single locus associated with HPT-JT (HRPT2) was previously mapped to chromosomal region 1q25-q32. We refined this region to a critical interval of 12 cM by genotyping in 26 affected kindreds. Using a positional candidate approach, we identified thirteen different heterozygous, germline, inactivating mutations in a single gene in fourteen families with HPT-JT. The proposed role of HRPT2 as a tumor suppressor was supported by mutation screening in 48 parathyroid adenomas with cystic features, which identified three somatic inactivating mutations, all located in exon 1. None of these mutations were detected in normal controls, and all were predicted to cause deficient or impaired protein function. HRPT2 is a ubiquitously expressed, evolutionarily conserved gene encoding a predicted protein of 531 amino acids, for which we propose the name parafibromin. Our findings suggest that HRPT2 is a tumor-suppressor gene, the inactivation of which is directly involved in predisposition to HPT-JT and in development of some sporadic parathyroid tumors.


Assuntos
Adenoma/genética , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Hiperparatireoidismo/genética , Neoplasias das Paratireoides/genética , Proteínas/genética , Adenoma/patologia , Sequência de Aminoácidos , Sequência de Bases , Cromossomos Humanos Par 1 , Éxons , Etiquetas de Sequências Expressas , Genes Supressores de Tumor , Ligação Genética , Testes Genéticos , Genótipo , Heterozigoto , Humanos , Repetições de Microssatélites , Dados de Sequência Molecular , Fases de Leitura Aberta , Neoplasias das Paratireoides/química , Neoplasias das Paratireoides/patologia , Linhagem , Proteínas/química , Síndrome , Proteínas Supressoras de Tumor
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