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1.
Environ Monit Assess ; 196(7): 672, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940996

RESUMO

The disaggregated inorganic grain size (DIGS) of bottom sediment analyzed with a Coulter Counter (CC) has been used to show that the fraction of sediment deposited in flocs (floc fraction) increased in both the near and far field after the introduction of open cage salmon aquaculture, altering benthic habitat and species composition. As a result, DIGS was identified as a potential indicator of regional environmental changes due to aquaculture. Laser diffraction is an attractive alternative to the CC because of its greater efficiency and larger size range. To determine if a laser diffraction instrument, Beckman-Coulter LS 13 320 (LS), could replace the CC within a Canadian national aquaculture monitoring program, the DIGS of 581 samples from five different regions in eastern Canada were analyzed with an LS and a CC. Results show that the LS could not be used to calculate floc fraction. Instead, % sortable silt and the volume % of inorganic particles < 16 µm were evaluated as alternative proxies for fine sediment properties. LS and CC values for these parameters were correlated, but they were significantly different and the relationship between the instruments was dependent on the area sampled. The LS did not capture variations between areas seen in the CC DIGS data. Where the DIGS from the CC found no sorting in the finest size classes, all the LS samples had similar size distributions characterized by smooth modal peaks. The LS and CC both return values that can be used to monitor changes in the deposition of fine-grained sediment, but the LS cannot determine changes in floc deposition and caution is required if comparing different sedimentary environments.


Assuntos
Aquicultura , Monitoramento Ambiental , Sedimentos Geológicos , Tamanho da Partícula , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Canadá , Animais , Lasers
2.
Br J Surg ; 108(5): 554-565, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34043776

RESUMO

BACKGROUND: Bariatric surgery can be effective in weight reduction and diabetes remission in some patients, but is expensive. The costs of bariatric surgery in patients with obesity and type 2 diabetes mellitus (T2DM) were explored here. METHODS: Population-based retrospectively gathered data on patients with obesity and T2DM from the Hong Kong Hospital Authority (2006-2017) were evaluated. Direct medical costs from baseline up to 60 months were calculated based on the frequency of healthcare service utilization and dispensing of diabetes medication. Charlson Co-morbidity Index (CCI) scores and co-morbidity rates were measured to compare changes in co-morbidities between surgically treated and control groups over 5 years. One-to-five propensity score matching was applied. RESULTS: Overall, 401 eligible surgical patients were matched with 1894 non-surgical patients. Direct medical costs were much higher for surgical than non-surgical patients in the index year (€36 752 and €5788 respectively; P < 0·001) mainly owing to the bariatric procedure. The 5-year cumulative costs incurred by surgical patients were also higher (€54 135 versus €28 603; P < 0·001). Although patients who had bariatric surgery had more visits to outpatient and allied health professionals than those who did not across the 5-year period, surgical patients had shorter length of stay in hospitals than non-surgical patients in year 2-5. Surgical patients had significantly better CCI scores than controls after the baseline measurement (mean 3·82 versus 4·38 at 5 years; P = 0·016). Costs of glucose-lowering medications were similar between two groups, except that surgical patients had significantly lower costs of glucose-lowering medications in year 2 (€973 versus €1395; P = 0.012). CONCLUSION: Bariatric surgery in obese patients with T2DM is expensive, but leads to an improved co-morbidity profile, and reduced length of hospitalization.


Assuntos
Cirurgia Bariátrica/economia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Obesidade/economia , Assistência Ambulatorial/economia , Assistência Ambulatorial/estatística & dados numéricos , Estudos de Casos e Controles , Comorbidade , Diabetes Mellitus Tipo 2/economia , Serviço Hospitalar de Emergência/economia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Hong Kong/epidemiologia , Humanos , Hipoglicemiantes/economia , Hipoglicemiantes/uso terapêutico , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Obesidade/cirurgia , Visita a Consultório Médico/economia , Visita a Consultório Médico/estatística & dados numéricos , Estudos Retrospectivos
3.
Clin Radiol ; 73(7): 640-646, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29636188

RESUMO

AIM: To investigate four methods to measure the maximum dimension (MD) of metastatic neck nodes and correlate with clinical outcome in nasopharyngeal carcinoma (NPC). MATERIALS AND METHODS: Magnetic resonance imaging (MRI) examinations of 712 NPC patients were analysed. MD measurements using methods 1, 2, 3, and 4 were obtained from a single node in the axial plane; a single node in the axial/coronal plane; a single and/or confluent nodes in the axial/coronal plane; and a single and/or confluent and/or contiguous nodes in the axial/coronal plane, respectively. MDs obtained from the four methods were correlated with nodal volume (NV) using Pearson's correlation test. MDs obtained from the four methods, T and N stages, age, gender, and treatment were correlated with overall survival (OS), disease-specific survival (DSS), distant metastases free survival (DMFS), and regional relapse-free survival (RRFS) using cox regression. RESULTS: Method 4 (R: 0.84) had the strongest correlation with NV followed by method 3 (R: 0.77), method 2 (R: 0.70) and method 1(R: 0.69). Method 4 was the only independent nodal measurement of OS, DSS, and DMFS (p-values = 0.008, <0.001 and <0.001, respectively). None of the MD methods was an independent measurement of RRFS. CONCLUSIONS: The best method to obtain the MD for staging incorporates not only single and confluent, but also contiguous metastatic nodes measured in the plane with the MD.


Assuntos
Metástase Linfática/diagnóstico por imagem , Metástase Linfática/patologia , Imageamento por Ressonância Magnética/métodos , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Pescoço , Estadiamento de Neoplasias , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
4.
Dis Esophagus ; 30(9): 1-8, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28859363

RESUMO

Optimal interval between neoadjuvant chemoradiotherapy (CRT) and surgery is not elucidated for esophageal squamous carcinoma. The aim of this study is to evaluate the impact of this time interval on patient outcome. Patients treated with neoadjuvant CRT followed by surgery between 2002 and 2009 were analyzed. Patients were divided into two groups based on the median interval to surgery (64 days): A  64 days (n = 53). A second analysis was performed by re-classifying patients into three interval groups: A* ≤ 40 days (n = 16); B* 41-80 days (n = 60); C* > 80 days (n = 31). Operative outcome, pathological data, and long-term survival were analyzed. One hundred and seven (n = 107) patients were analyzed. Five patients (9.4%) in group B had an anastomotic leak compared with no leakage from group A (P < 0.021). The complete pathological response was comparable in groups A and B (35% vs. 24.5%, p = 0.23). R0 was significantly lower in group A* (A*: 56.3%, B*: 90%, C*: 74.2%, P = 0.006). In patients with R0 resection, 5-year survival was significantly better in group A than B (71.7% vs. 51%, P = 0.032) and in group A* (A* 100% vs. B* 60.2% & C* 48.3%; A* vs. B*, P = 0.036; A* vs. C*, P = 0.019). Complete pathological response was an independent predictor of survival. Early surgery with R0 resection following neoadjuvant CRT may lead to a better outcome. Further prospective studies are still necessary to provide better insight into the issue. At present, timing of surgery should be individualized and performed at the earliest opportunity.


Assuntos
Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/terapia , Esofagectomia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia Adjuvante , Cisplatino/administração & dosagem , Esofagectomia/efeitos adversos , Feminino , Fluoruracila/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Neoplasia Residual , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
7.
Environ Sci Technol ; 47(11): 5828-34, 2013 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-23647260

RESUMO

Many contaminants in aquatic environments are associated with loosely packed aggregates of particulate material called flocs. Flocculation allows contaminants to accumulate at the sediment-water interface and it packages them in a form that is readily available for ingestion by filter feeding organisms. Unfortunately, most samplers being used for environmental assessment and monitoring suspend this material on impact and fail to sample this critical component of the seabed. In this study we use a slo-corer to collect seabed samples with an undisturbed surface layer and a Gust microcosm erosion chamber to erode the surface of the cores at increasing shear stresses. Results from two different sites, one impacted by tailings from historic gold mining and the other by open-pen salmon aquaculture, showed the levels of metals suspended at stresses below 0.24 Pa were greater than in the underlying sediment. Sampling this highly mobile surface layer is critical for determining the total contaminant load in bottom sediments and, more importantly, this layer represents the most readily available material for suspension. The loss of this layer during sampling could lead to inaccurate measurements of contaminant levels during environmental assessment and effects monitoring. A re-evaluation of the ISO standard for bottom sediment sampling is recommended.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Metais/análise , Poluentes Químicos da Água/análise , Aquicultura , Monitoramento Ambiental/instrumentação , Mercúrio/análise , Mineração , Novo Brunswick , Nova Escócia
8.
Resusc Plus ; 16: 100459, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37663146

RESUMO

Introduction: Current neonatal resuscitation guidelines recommend the use of epinephrine during neonatal cardiopulmonary resuscitation (CPR). However, newborns receiving epinephrine continue to have high rates of mortality and neurodevelopmental disability. The infrequent need for neonatal CPR, coupled with an inability to consistently anticipate which newborn infants are at risk of requiring CPR, explains the lack of high-quality evidence (i.e., large randomized clinical trials) to better guide healthcare providers in their resuscitative effort. Therefore, we need neonatal data to determine the optimal vasopressor therapy during neonatal CPR. The current pilot trial will examine the efficacy of vasopressin versus epinephrine during CPR of asphyxiated newborn infants. Methods and analysis: The trial will be a prospective, cluster, open label, single-center, randomized controlled trial on two alternative cardiovascular supportive medications. This study will assess the primary outcome of time to return of spontaneous circulation (ROSC) in newborns requiring CPR in the delivery room who were treated with either vasopressin (intervention) or epinephrine (control). Secondary outcomes such as infant mortality and other clinical outcome measures will also be collected. An estimated 20 newborns will be recruited, and comparisons will be made between asphyxiated infants treated with either drugs. Ethics and dissemination: This study has been approved by the Research Ethics Board at the University of Alberta (June 16, 2023). Study findings will be published in peer-reviewed journals, presented at conferences, and communicated to relevant participants and stakeholders.Trial registration: ClinicalTrial.gov Identifier: NCT05738148. Registered February 21, 2023.

9.
Artigo em Inglês | MEDLINE | ID: mdl-37946094

RESUMO

Ethnic minority women experience disparities in mammography screening utilisation and breast cancer outcomes. This systematic review and meta-analysis synthesised multidomain and multilevel factors that intersect to influence the utilisation of mammography among ethnic minorities. A literature search was conducted in five databases (PubMed, Ovid MEDLINE, EMBASE, CINAHL, and PsycINFO) from inception to May 2022. Guided by the National Institute on Minority Health and Health Disparity research framework, the retrieved data were synthesised using narrative summaries and meta-analyses. Among the 27 studies, most (n = 24) reported individual, interpersonal, and community factors in the health care system domain. In the sociocultural domain, interpersonal and societal (n = 8) factors, such as modesty and karma beliefs, were less frequently identified than individual (n = 20) factors in relation to acculturation. Only individual-level factors were reported for the biological and physical/built environment (e.g., rural residence) domains. In the behavioural domain, cancer screening behaviours had a high combined prediction ability (odds ratio = 18.23; I2 = 23%), whereas interpersonal (e.g., family obligations) and community (e.g., neighbourhood violence) factors discouraged mammography screening. Special focus should be given to ethnic minority women, especially those living in rural areas, those with considerable family obligations, and those who have suffered from violence and other life pressures, to increase their access to mammography services. Multidomain and multilevel efforts, culturally appropriate strategies, and equity-advancing policies such as geographic access and insurance coverage would help to mitigate the ethnic disparities in mammography screening.

10.
Mar Pollut Bull ; 188: 114654, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36736258

RESUMO

The presence of in-feed anti-sea lice drugs and their relationship with organic enrichment is poorly understood in sediment surrounding salmon farms. Using data from an aquaculture monitoring program (2018-2020), we describe this relationship at ten sites in four Canadian provinces. Three anti-sea lice pesticides (lufenuron, teflubenzuron, emamectin benzoate and metabolite desmethyl emamectin benzoate), and one antibiotic (oxytetracycline) were detected. Concentrations were often below limits of quantification. Values are also lower than those reported in other aquaculture salmon-producing countries. Highest concentrations, along with organic enrichment, were observed ~200 m of cages with lower concentrations detected up to 1.5 km away. Most samples had at least two drugs present: 75.2 % (British Columbia), 91.4 % (Newfoundland), and 54.8 % (New Brunswick/Nova Scotia) highlighting the potential for cumulative effects. Emamectin benzoate and oxytetracycline were detected four and three years respectively after last known treatments, demonstrating the need for research on overall persistence of compounds.


Assuntos
Copépodes , Doenças dos Peixes , Oxitetraciclina , Salmo salar , Animais , Antibacterianos/farmacologia , Oxitetraciclina/farmacologia , Aquicultura , Sedimentos Geológicos , Colúmbia Britânica
11.
Ecol Lett ; 15(6): 520-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22472207

RESUMO

Trees with sufficient nutrition are known to allocate carbon preferentially to aboveground plant parts. Our global study of 49 forests revealed an even more fundamental carbon allocation response to nutrient availability: forests with high-nutrient availability use 58 ± 3% (mean ± SE; 17 forests) of their photosynthates for plant biomass production (BP), while forests with low-nutrient availability only convert 42 ± 2% (mean ± SE; 19 forests) of annual photosynthates to biomass. This nutrient effect largely overshadows previously observed differences in carbon allocation patterns among climate zones, forest types and age classes. If forests with low-nutrient availability use 16 ± 4% less of their photosynthates for plant growth, what are these used for? Current knowledge suggests that lower BP per unit photosynthesis in forests with low- versus forests with high-nutrient availability reflects not merely an increase in plant respiration, but likely results from reduced carbon allocation to unaccounted components of net primary production, particularly root symbionts.


Assuntos
Biomassa , Ciclo do Carbono , Árvores/crescimento & desenvolvimento , Processos Autotróficos , Carbono/metabolismo , Respiração Celular , Clima , Agricultura Florestal , Fotossíntese , Raízes de Plantas/microbiologia , Árvores/metabolismo , Árvores/microbiologia
12.
Eur J Clin Microbiol Infect Dis ; 31(4): 591-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21796343

RESUMO

We aimed to assess the immunogenicity of a single half-dose of AS03-adjuvanted monovalent 2009 pandemic H1N1 vaccine in healthy adults. Healthy subjects age 20-60 years were prospectively enrolled in a cohort receiving intramuscular administration of a single half-dose (1.875 µg of hemagglutinin [HA]) of adjuvanted 2009 pandemic H1N1 influenza vaccine. Data from participants enrolled in a concomitant study of immunogenicity following a full-dose (3.75 µg of HA) are presented concurrently. Sera for assessment of hemagglutination-inhibiting (HAI) antibody to the vaccine strain were obtained before and 14 or 21 days after vaccination. Ninety-seven participants received a half-dose and 50 received a full-dose of vaccine. In the half-dose cohort, Food and Drug Administration criteria for immunogenicity regarding seroprotection and seroconversion rates were met for subjects aged 20-45 years, but not for those aged 46-60 years. There was no statistically significant difference in the proportion of individuals achieving a post-vaccination HAI titre of ≥1:40, the geometric mean titres of post-vaccination antibody, or the proportion of individuals with a four-fold or greater increase in antibody levels between the two cohorts. Participants 46-60 years of age were significantly less likely to be seroprotected at day 21 than those 20-45 years old in both cohorts. Immunogenicity of a half dose of adjuvanted pH1N1 influenza vaccine was adequate in subjects aged 20-45 years. Dose reduction is a possible strategy for expanding the availability in the event of vaccine shortage in this age group.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Adjuvantes Imunológicos/administração & dosagem , Adulto , Fatores Etários , Anticorpos Antivirais/sangue , Estudos de Coortes , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Injeções Intramusculares , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
13.
Ecol Appl ; 21(5): 1506-22, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21830698

RESUMO

We present an analysis of the relative magnitude and contribution of parameter and driver uncertainty to the confidence intervals on estimates of net carbon fluxes. Model parameters may be difficult or impractical to measure, while driver fields are rarely complete, with data gaps due to sensor failure and sparse observational networks. Parameters are generally derived through some optimization method, while driver fields may be interpolated from available data sources. For this study, we used data from a young ponderosa pine stand at Metolius, Central Oregon, and a simple daily model of coupled carbon and water fluxes (DALEC). An ensemble of acceptable parameterizations was generated using an ensemble Kalman filter and eddy covariance measurements of net C exchange. Geostatistical simulations generated an ensemble of meteorological driving variables for the site, consistent with the spatiotemporal autocorrelations inherent in the observational data from 13 local weather stations. Simulated meteorological data were propagated through the model to derive the uncertainty on the CO2 flux resultant from driver uncertainty typical of spatially extensive modeling studies. Furthermore, the model uncertainty was partitioned between temperature and precipitation. With at least one meteorological station within 25 km of the study site, driver uncertainty was relatively small ( 10% of the total net flux), while parameterization uncertainty was larger, 50% of the total net flux. The largest source of driver uncertainty was due to temperature (8% of the total flux). The combined effect of parameter and driver uncertainty was 57% of the total net flux. However, when the nearest meteorological station was > 100 km from the study site, uncertainty in net ecosystem exchange (NEE) predictions introduced by meteorological drivers increased by 88%. Precipitation estimates were a larger source of bias in NEE estimates than were temperature estimates, although the biases partly compensated for each other. The time scales on which precipitation errors occurred in the simulations were shorter than the temporal scales over which drought developed in the model, so drought events were reasonably simulated. The approach outlined here provides a means to assess the uncertainty and bias introduced by meteorological drivers in regional-scale ecological forecasting.


Assuntos
Carbono/metabolismo , Ecossistema , Modelos Biológicos , Árvores/metabolismo , Incerteza , Simulação por Computador , Interpretação Estatística de Dados , Pinus/metabolismo , Chuva , Solo , Água
15.
Clin Ter ; 171(2): e110-e113, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32141481

RESUMO

Osteoradionecrosis (ORN) is a well-recognized, debilitating complication of radiotherapy for patients with head and neck cancer. There is no universally accepted treatment for ORN of the jawbones. We report on a case of refractory mandibular ORN treated by sequestrectomy of mandible and autogenous transplantation of fat graft combined with platelet-rich fibrin (PRF). Improved perfusion was observed using the laser Doppler flowmetry. This case highlights the use of autogenous free fat graft and PRF as an adjunct therapy to sequestrectomy in the management of ORN.


Assuntos
Tecido Adiposo/transplante , Doenças Mandibulares/terapia , Osteorradionecrose/terapia , Fibrina Rica em Plaquetas , Terapia Combinada , Humanos , Masculino , Mandíbula/cirurgia , Doenças Mandibulares/cirurgia , Pessoa de Meia-Idade , Fatores de Risco , Cicatrização
16.
Oncogene ; 26(41): 6021-30, 2007 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-17384681

RESUMO

Protein serine/threonine phosphatase 2A (PP2A) activity must be tightly controlled to maintain cell homeostasis. Here, we report the identification of a previously uncharacterized mammalian protein, type 2A-interacting protein (TIP), as a novel regulatory protein of PP2A and the PP2A-like enzymes PP4 and PP6. TIP is a ubiquitously expressed protein and parallels the distribution of the PP2A catalytic subunit. Unlike its role in yeast, TIP does not interact with the mammalian homolog of type 2A-associated protein of 42 kDa (Tap42), alpha4, but instead associates with PP2A, PP4 and PP6 catalytic subunits independently of mammalian target of rapamycin kinase activity. Interestingly, the 20 kDa TIP splice variant TIP_i2, which lacks amino acids 173-272 of TIP's C-terminus, does not interact with PP2A; this finding indicates that residues 173-272 are important for the assembly of the TIP.phosphatase complex. In contrast to purified PP2A holoenzymes, TIP.PP2A complexes are devoid of phosphatase activity. Furthermore, alterations in the cellular levels of TIP influence the phosphorylation state of a specific protein substrate of ataxia-telangiectasia mutated (ATM)/ATM- and Rad3-related (ATR) kinases. Elevated levels of TIP result in an increase in the phosphorylation state of this protein substrate, whereas TIP-depleted cells exhibit a significant decrease in this protein's phosphorylation state, which is reversed by treatment with the PP2A inhibitor okadaic acid. These results indicate TIP is a novel inhibitory regulator of PP2A and implicate a role for TIP.PP2A complexes within the ATM/ATR signaling pathway controlling DNA replication and repair.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/fisiologia , Proteínas de Ligação a DNA/fisiologia , Glutaminase/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Supressoras de Tumor/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/isolamento & purificação , Proteínas Mutadas de Ataxia Telangiectasia , Linhagem Celular , Glutaminase/isolamento & purificação , Homeostase , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/isolamento & purificação , Rim , Fosforilação , Proteína Fosfatase 2 , Transdução de Sinais , Transfecção
17.
AJNR Am J Neuroradiol ; 39(3): 515-523, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29284600

RESUMO

BACKGROUND AND PURPOSE: MR imaging can detect nasopharyngeal carcinoma that is hidden from endoscopic view, but for accurate detection carcinoma confined within the nasopharynx (stage T1) must be distinguished from benign hyperplasia of the nasopharynx. This study aimed to document the MR imaging features of stage T1 nasopharyngeal carcinoma and to attempt to identify features distinguishing it from benign hyperplasia. MATERIALS AND METHODS: MR images of 189 patients with nasopharyngeal carcinoma confined to the nasopharynx and those of 144 patients with benign hyperplasia were reviewed and compared in this retrospective study. The center, volume, size asymmetry (maximum percentage difference in area between the right and left nasopharyngeal halves), signal intensity asymmetry, deep mucosal white line (greater contrast enhancement along the deep tumor margin), and absence/distortion of the adenoidal septa were evaluated. Differences were assessed with logistic regression and the χ2 test. RESULTS: The nasopharyngeal carcinoma center was lateral, central, or diffuse in 134/189 (70.9%), 25/189 (13.2%), and 30/189 (15.9%) cases, respectively. Nasopharyngeal carcinomas involving the walls showed that a deep mucosal white line was present in 180/183 (98.4%), with a focal loss of this line in 153/180 (85%) cases. Adenoidal septa were absent or distorted in 111/111 (100%) nasopharyngeal carcinomas involving the adenoid. Compared with benign hyperplasia, nasopharyngeal carcinoma had a significantly greater volume, size asymmetry, signal asymmetry, focal loss of the deep mucosal white line, and absence/distortion of the adenoidal septa (P < .001). Although size asymmetry was the most accurate criterion (89.5%) for nasopharyngeal carcinoma detection, use of this parameter alone would have missed 11.9% of early-stage T1 nasopharyngeal carcinomas. CONCLUSIONS: MR imaging features can help distinguish stage T1 nasopharyngeal carcinoma from benign hyperplasia in most cases.


Assuntos
Hiperplasia/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Carcinoma Nasofaríngeo/diagnóstico por imagem , Neoplasias Nasofaríngeas/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nasofaringe/diagnóstico por imagem , Nasofaringe/patologia , Estudos Retrospectivos , Adulto Jovem
18.
J Clin Pathol ; 60(3): 315-20, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16698948

RESUMO

BACKGROUND: Histological differentiation of mammary papillary lesions can be difficult. The evaluation of myoepithelial cells can be helpful, with benign papilloma showing a continuous myoepithelial cell layer, which becomes attenuated or absent in malignant papillary lesions. METHODS: A large series of 100 papillomas (28 papillomas with florid epithelial hyperplasia) and 68 papillary carcinomas (9 invasive, 44 in situ, and 15 ductal carcinomas in situ (DCIS) involving papillomas) of the breast were stained for myoepithelial cells by immunohistochemistry using antibodies to smooth-muscle actin (SMA), p63, CD10 and cytokeratin (CK) 14. RESULTS: In the papillomas, using these four antibodies, myoepithelial cells were positive in 88%, 99%, 91% and 95% of cases, respectively, with SMA showing marked stromal component cell staining and CD10 showing epithelial and stromal staining. CK14 also showed epithelial staining in 71% of papillomas and 96% of papillomas with florid epithelial hyperplasia. In the papillary carcinomas, 36 (53%) cases showed staining of myoepithelial cells that were scattered, discontinuous and diminished in number and the remaining 32 (47%) cases did not show myoepithelial cells. Invasive papillary carcinoma has the lowest proportion (33%) with myoepithelial cells, and DCIS involving papillomas had the highest proportion (87%). CONCLUSIONS: p63 had the highest sensitivity and did not cross-react with stromal cells and only rarely with epithelial cells. CK14 has the added ability to distinguish between florid epithelial hyperplasia involving papilloma and DCIS involving papillomas. CK14 and p63 may be used as an adjunct in assessing difficult papillary lesions of the breast.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Actinas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/metabolismo , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Papilar/metabolismo , Carcinoma Papilar/patologia , Proteínas de Ligação a DNA/metabolismo , Diagnóstico Diferencial , Feminino , Humanos , Queratina-14/metabolismo , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Neprilisina/metabolismo , Papiloma/metabolismo , Papiloma/patologia , Papiloma Intraductal/metabolismo , Papiloma Intraductal/patologia , Transativadores/metabolismo , Fatores de Transcrição , Proteínas Supressoras de Tumor/metabolismo
19.
Phys Rev E Stat Nonlin Soft Matter Phys ; 75(6 Pt 1): 061606, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17677272

RESUMO

Carpenter [Phys. Rev. E 61, 532 (2000)] succeeded in determining a single universal model, called the P1 model, that could describe the ellipsometric critical adsorption data from the liquid-vapor interface of four different critical binary liquid mixtures near their critical demixing temperatures. The P1 model also recently has been used to describe neutron reflectometry data from a critical liquid mixture/crystalline quartz interface. However, in another recent study, the P1 model failed to simultaneously describe x-ray reflectometry and ellipsometry data from the liquid-vapor surface of the critical mixture n -dodecane + tetrabromoethane (DT). In this paper, we resolve this discrepancy between x-ray and ellipsometric data for the DT system. At large length scales (far from the interface) the local concentration is described by the P1 model in order to correctly reproduce the temperature dependence of the ellipsometric data. Close to the interface, however, the molecular structure must be correctly accounted for in order to quantitatively explain the x-ray data. An important conclusion that arises from this study is that neutron or x-ray reflectometry is most sensitive to short-range interfacial structure, but may provide misleading information about long-range interfacial structure. Ellipsometry provides a more accurate measure of this long-range interfacial structure. Complex interfacial structures, possessing both short- and long-range structure, are therefore best studied using multiple techniques.

20.
Sci Rep ; 7(1): 9632, 2017 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-28851977

RESUMO

Concentrations of atmospheric carbon dioxide (CO2) have continued to increase whereas atmospheric deposition of sulphur and nitrogen has declined in Europe and the USA during recent decades. Using time series of flux observations from 23 forests distributed throughout Europe and the USA, and generalised mixed models, we found that forest-level net ecosystem production and gross primary production have increased by 1% annually from 1995 to 2011. Statistical models indicated that increasing atmospheric CO2 was the most important factor driving the increasing strength of carbon sinks in these forests. We also found that the reduction of sulphur deposition in Europe and the USA lead to higher recovery in ecosystem respiration than in gross primary production, thus limiting the increase of carbon sequestration. By contrast, trends in climate and nitrogen deposition did not significantly contribute to changing carbon fluxes during the studied period. Our findings support the hypothesis of a general CO2-fertilization effect on vegetation growth and suggest that, so far unknown, sulphur deposition plays a significant role in the carbon balance of forests in industrialized regions. Our results show the need to include the effects of changing atmospheric composition, beyond CO2, to assess future dynamics of carbon-climate feedbacks not currently considered in earth system/climate modelling.

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