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1.
Drug Alcohol Depend ; 226: 108864, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34245998

RESUMO

AIMS: We examine the extent to which adolescent and young adult psychosocial factors are associated with variation in the experience of common types of harm (e.g., injuries, violence, sexual regrets) with respect to binge-drinking frequency - termed residual harm. METHODS: Data were from the Australian Temperament Project, a population-based cohort study that has followed a sample of young Australians from infancy to adulthood since 1983. The current sample comprised 1,081 (565 women). Residual harm was operationalised by saving residuals from models regressing number of alcohol harms onto binge-drinking frequency at each of 5 waves, two in adolescence (15-16 and 17-18 years) and three in young adulthood (19-20, 23-24, and 27-28 years). Psychosocial factors (mental health, social skills, quality of parent and peer relationships) were assessed prior to binge drinking in early adolescence (13-14 years) and then again in young adulthood (19-20 years). RESULTS: Adolescent predictors of decreased residual harm were lower depressive symptoms, and higher cooperation, self-control, and peer and parent attachment. Young adult predictors of decreased residual harm were lower depressive, anxiety, and stress symptoms and peer and parent negative appraisal, and higher responsibility, and peer and parent emotional support. Associations were evident in males and females, although the strength of some associations diminished with age. CONCLUSIONS: Adolescents and young adults with better mental health, social skills, and relationship quality experienced less harm with respect to their binge-drinking frequency. Future research should examine the potential of investment in strength-based interventions for young people.


Assuntos
Consumo Excessivo de Bebidas Alcoólicas , Temperamento , Adolescente , Adulto , Transtornos de Ansiedade , Austrália/epidemiologia , Consumo Excessivo de Bebidas Alcoólicas/epidemiologia , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Masculino , Adulto Jovem
2.
Addict Behav ; 112: 106597, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32823031

RESUMO

AIMS: To explore the process of applying counterfactual thinking in examining causal determinants of substance use trajectories in observational cohort data. Specifically, we examine the extent to which quality of the parent-adolescent relationship and affiliations with deviant peers are causally related to trajectories of alcohol, tobacco, and cannabis use across adolescence and into young adulthood. METHODS: Data were drawn from the Australian Temperament Project, a population-based cohort study that has followed a sample of young Australians from infancy to adulthood since 1983. Parent-adolescent relationship quality and deviant peer affiliations were assessed at age 13-14 years. Latent curve models were fitted for past month alcohol, tobacco, and cannabis use (n = 1590) from age 15-16 to 27-28 years (5 waves). Confounding factors were selected in line with the counterfactual framework. RESULTS: Following confounder adjustment, higher quality parent-adolescent relationships were associated with lower baseline cannabis use, but not alcohol or tobacco use trajectories. In contrast, affiliations with deviant peers were associated with higher baseline binge drinking, tobacco, and cannabis use, and an earlier peak in the cannabis use trajectory. CONCLUSIONS: Despite careful application of the counterfactual framework, interpretation of associations as causal is not without limitations. Nevertheless, findings suggested causal effects of both parent-adolescent relationships and deviant peer affiliations on the trajectory of substance use. Causal effects were more pervasive (i.e., more substance types) and protracted for deviant peer affiliations. The exploration of causal relationships in observational cohort data is encouraged, when relevant limitations are transparently acknowledged.


Assuntos
Grupo Associado , Transtornos Relacionados ao Uso de Substâncias , Adolescente , Adulto , Austrália/epidemiologia , Estudos de Coortes , Humanos , Estudos Longitudinais , Pais , Fatores de Risco , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adulto Jovem
3.
Water Sci Technol ; 81(9): 1951-1960, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32666948

RESUMO

Two bioreactors were investigated as an alternative for the post-treatment of effluent from an upflow anaerobic sludge blanket (UASB) reactor treating domestic sewage, aiming at dissolved sulfide and methane removal. The bioreactors (R-control and R-air) were operated at different hydraulic retention times (HRT; 6 and 3 h) with or without aeration. Large sulfide and methane removal efficiencies were achieved by the microaerated reactor at HRT of 6 h. At this HRT, sulfide removal efficiencies were equal to 61% and 79%, and methane removal efficiencies were 31% and 55% for R-control and R-air, respectively. At an HRT of 3 h, sulfide removal efficiencies were 22% (R-control) and 33% (R-air) and methane removal did not occur. The complete oxidation of sulfide, with sulfate formation, prevailed in both phases and bioreactors. However, elemental sulfur formation was more predominant at an HRT of 6 h than at an HRT of 3 h. Taken together, the results show that post-treatment improved the anaerobic effluent quality in terms of chemical oxygen demand and solids removal. However, ammoniacal nitrogen was not removed due to either the low concentration of air provided or the absence of microorganisms involved in the nitrogen cycle.


Assuntos
Metano , Esgotos , Anaerobiose , Reatores Biológicos , Sulfetos , Eliminação de Resíduos Líquidos
4.
Drug Alcohol Depend ; 201: 58-64, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31195345

RESUMO

BACKGROUND: Modelling trajectories of substance use over time is complex and requires judicious choices from a number of modelling approaches. In this study we examine the relative strengths and weakness of latent curve models (LCM), growth mixture modelling (GMM), and latent class growth analysis (LCGA). DESIGN: Data were drawn from the Australian Temperament Project, a 36-year-old community-based longitudinal study that has followed a sample of young Australians from infancy to adulthood across 16 waves of follow-up since 1983. Models were fitted on past month alcohol use (n = 1468) and cannabis use (n = 549) across six waves of data collected from age 13-14 to 27-28 years. FINDINGS: Of the three model types, GMMs were the best fit. However, these models were limited given the variance of numerous growth parameters had to be constrained to zero. Additionally, both the GMM and LCGA solutions had low entropy. The negative binomial LCMs provided a relatively well-fitting solution with fewer drawbacks in terms of growth parameter estimation and entropy issues. In all cases, model fit was enhanced when using a negative binomial distribution. CONCLUSIONS: Substance use researchers would benefit from adopting a complimentary framework by exploring both LCMs and mixture approaches, in light of the relative strengths and weaknesses as identified. Additionally, the distribution of data should inform modelling decisions.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Uso da Maconha/epidemiologia , Modelos Estatísticos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adolescente , Adulto , Austrália/epidemiologia , Feminino , Humanos , Análise de Classes Latentes , Estudos Longitudinais , Masculino , Reprodutibilidade dos Testes , Adulto Jovem
5.
Oncol Rep ; 35(5): 2699-706, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26985678

RESUMO

Children with acute lymphoblastic leukemia (ALL) often present fever. Febrile states are usually associated with infectious processes that generate an inflammatory response involving various molecules, including cytokines. However, an inflammatory response may also occur in the absence of infection. We hypothesized that the levels of inflammatory cytokines are increased in children with ALL without apparent infection. The serum levels of 13 cytokines in 99 patients with ALL and 48 non-oncological patients without apparent infection were measured using multiplex analyte profiling technology (Luminex®). The concentration of circulating pro-inflammatory cytokines associated with fever was similar between patients with ALL and fever at diagnosis and those without fever. The levels of tumor necrosis factor α, interleukin (IL)-6, IL-8, monocyte chemoattractant protein-1 (MCP-1) and IL-10 were higher in patients with ALL vs. the control group (P<0.05). Moreover, the levels of the T helper 1 (interferon­Î³ and IL-12) cytokines were higher in patients with ALL vs. the control group. Transforming growth factor ß was lower in patients with ALL vs. the control group (P<0.05). The levels of IL-1ß, IL-2, IL-4, IL-13, and IL-17 were similar in the two groups. Our results indicate that the circulating levels of seven of the important studied cytokines are elevated in patients with newly diagnosed ALL without apparent infection, reflecting a strong and deregulated inflammatory state in this disease, with a Th1-polarization profile.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Células Th1/fisiologia , Adolescente , Polaridade Celular , Quimiocinas/sangue , Criança , Pré-Escolar , Feminino , Febre/sangue , Febre/imunologia , Humanos , Lactente , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangue
6.
J Nanosci Nanotechnol ; 15(5): 3636-40, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26504986

RESUMO

Ceria and rare earth-doped ceria powders have important applications in catalysis, gas sensoring, and electronics. Even if many authors report different methods for the synthesis of nano-sized doped-ceria only few of them give information about the necessary washing processes for the powder purification. The organics adsorbed on the as-synthesized particles surface strongly affect, in fact, the properties of the powder. In this work, CeO2 and Ce(1-x)Gd(x)O(2-d) (x = 0.10, 0.20, 0.30) solid solutions were produced by polyol microwave assisted method. The amount of synthesis residues adsorbed on the as-synthesized powders was firstly evaluated. The purification ability of different solvents on the as-synthesized Ce0.80Gd0.20O190 was, then, accurately studied in order to obtain a clean powder without the need of any thermal treatments. The study shows that water purification allows to reduce the amount of the residues of synthesis leading to the production of nano-particles with a mono-dispersed distribution of dimensions.

7.
Water Sci Technol ; 72(4): 535-42, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26247751

RESUMO

Despite the importance of anaerobic sludge extracellular polymeric substances (EPSs), their characterization is limited to information regarding their chemical classes and molecular size. This work explores the possibility of using proteomic techniques to study the proteins present in this matrix. Thus, this paper compares eight EPS extraction methods regarding extraction yield, protein/carbohydrate ratio, size distribution profile and suitability to sodium dodecyl sulfate-polyacrylamide gel electrophoresis analyses. Despite the differences found in quantification and size exclusion chromatography assays, the band profile found for all methods was very similar. Considering the band pattern, extraction time and background level, heating method followed by ammonium sulfate precipitation proved to be the most appropriate method for gel-based analyses of anaerobic sludge EPS proteins.


Assuntos
Carboidratos/análise , Polímeros/análise , Proteínas/análise , Proteômica/métodos , Anaerobiose , Cromatografia Líquida , Eletroforese em Gel de Poliacrilamida , Peso Molecular , Esgotos/análise , Espectrometria de Massas em Tandem
8.
Comput Methods Programs Biomed ; 118(1): 84-93, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25459525

RESUMO

In PET/CT thoracic imaging, respiratory motion reduces image quality. A solution consists in performing respiratory gated PET acquisitions. The aim of this study was to generate clinically realistic Monte-Carlo respiratory PET data, obtained using the 4D-NCAT numerical phantom and the GATE simulation tool, to assess the impact of respiratory motion and respiratory-motion compensation in PET on lesion detection and volume measurement. To obtain reconstructed images as close as possible to those obtained in clinical conditions, a particular attention was paid to apply to the simulated data the same correction and reconstruction processes as those applied to real clinical data. The simulations required 140,000h (CPU) generating 1.5 To of data (98 respiratory gated and 49 ungated scans). Calibration phantom and patient reconstructed images from the simulated data were visually and quantitatively very similar to those obtained in clinical studies. The lesion detectability was higher when the better trade-off between lesion movement limitation (compared to ungated acquisitions) and image statistic preservation is considered (respiratory cycle sampling in 3 frames). We then compared the lesion volumes measured on conventional PET acquisitions versus respiratory gated acquisitions, using an automatic segmentation method and a 40%-threshold approach. A time consuming initial manual exclusion of noisy structures needed with the 40%-threshold was not necessary when the automatic method was used. The lesion detectability along with the accuracy of tumor volume estimates was largely improved with the gated compared to ungated PET images.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Algoritmos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Simulação por Computador , Fluordesoxiglucose F18 , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional , Neoplasias Pulmonares/radioterapia , Método de Monte Carlo , Imagens de Fantasmas , Tomografia por Emissão de Pósitrons/estatística & dados numéricos , Compostos Radiofarmacêuticos , Planejamento da Radioterapia Assistida por Computador , Mecânica Respiratória
9.
J Chem Phys ; 140(22): 224504, 2014 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-24929404

RESUMO

The local vibrational dynamics of hematite (α-Fe2O3) has been investigated by temperature-dependent extended x-ray absorption fine structure spectroscopy and molecular dynamics simulations. The local dynamics of both the short and long nearest-neighbor Fe-O distances has been singled out, i.e., their local thermal expansion and the parallel and perpendicular mean-square relative atomic displacements have been determined, obtaining a partial agreement with molecular dynamics. No evidence of the Morin transition has been observed. More importantly, the strong anisotropy of relative thermal vibrations found for the short Fe-O distance has been related to its negative thermal expansion. The differences between the local dynamics of short and long Fe-O distances are discussed in terms of projection and correlation of atomic motion. As a result, we can conclude that the short Fe-O bond is stiffer to stretching and softer to bending than the long Fe-O bond.

10.
Drug Alcohol Depend ; 134: 178-84, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24479151

RESUMO

BACKGROUNDS: Parental drinking, harsh parental discipline and adolescent antisocial behaviour have been independently implicated in adolescent alcohol use. Robust prospective studies are required to examine developmental relationships between these factors and their effect on trajectories of alcohol use across adolescence. METHODS: Data were ascertained at three consecutive adolescent waves (13.5, 15.5 and 17.5 years) from the Australian Temperament Project, a 15-wave (30 year) general population birth cohort in Victoria, Australia. Adolescent alcohol trajectories, adjusted for time-varying measures of parenting and antisocial behaviour, were regressed on time-stable measures of parental alcohol use. The full case analysis comprised 751 individuals with complete data. RESULTS: Two distinct alcohol trajectories were identified across the three adolescent waves after adjusting for time-varying factors: a higher and lower drinking group. Both trajectories increased linearly over the study period. Antisocial behaviour was positively associated with both trajectories while harsh parental discipline was positively associated with alcohol use in the lower-use group only. Increased maternal and paternal drinking at 13.5 years placed teenagers at a greater risk of being included in the high-risk trajectory. CONCLUSION: Parental drinking was the strongest predictor of different drinking trajectories in adolescence. This finding underscores the importance of comprehensive public heath approaches that target both parental and adolescent drinking attitudes and behaviour.


Assuntos
Comportamento do Adolescente , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/tendências , Transtorno da Personalidade Antissocial/epidemiologia , Poder Familiar/tendências , Pais , Adolescente , Comportamento do Adolescente/psicologia , Consumo de Bebidas Alcoólicas/psicologia , Transtorno da Personalidade Antissocial/psicologia , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Poder Familiar/psicologia , Pais/psicologia , Vitória/epidemiologia
11.
J Environ Manage ; 128: 462-70, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23810998

RESUMO

This work investigated the anaerobic degradation of the model azo dye Remazol Yellow Gold RNL in an upflow anaerobic sludge blanket reactor (UASB) and two submerged anaerobic membrane (SAMBR) bioreactors, one of which (SAMBR-1) was operated with powdered activated carbon (PAC) in its interior. The reactors were operated at 35 °C with a hydraulic retention time of 24 h in three operational phases, aimed to assess the effect of external sources of carbon (glucose) or redox mediator (yeast extract) on the removal or color and organic matter. The results showed that removal efficiencies of COD (73-94%) and color (90-94%) were higher for SAMBR-1 when compared to SAMBR-2 (operated without PAC) and UASB reactors. In addition, the presence of PAC in SAMBR-1 increased reactor stability, thereby leading to a lower accumulation of volatile fatty acids (VFA). The microfiltration membrane was responsible for an additional removal of ~50% of soluble residual COD in the form of VFA, thus improving permeate quality. On its turn, PAC exhibited the ability to adsorb byproducts (aromatic amines) of azo dye degradation as well as to act as source of immobilized redox mediator (quinone groups on its surface), thereby enhancing color removal.


Assuntos
Compostos Azo/metabolismo , Reatores Biológicos , Corantes/metabolismo , Ácidos Sulfanílicos/metabolismo , Eliminação de Resíduos Líquidos/instrumentação , Aminas/metabolismo , Anaerobiose , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos/microbiologia , Carbono/metabolismo , Carvão Vegetal , Cor , Desenho de Equipamento , Ácidos Graxos Voláteis/metabolismo , Filtração/instrumentação , Riboflavina/metabolismo , Esgotos , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo
12.
Br J Cancer ; 108(11): 2334-8, 2013 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-23695017

RESUMO

BACKGROUND: Allergies have been described as protective factors against the development of childhood acute leukaemia (AL). Our objective was to investigate the associations between allergy history and the development of AL and acute lymphoblastic leukaemia (ALL) in children with Down syndrome (DS). METHODS: A case-control study was performed in Mexico City. The cases (n=97) were diagnosed at nine public hospitals, and the controls (n=222) were recruited at institutions for children with DS. Odds ratios (OR) were calculated. RESULTS: Asthma was positively associated with AL development (OR=4.18; 95% confidence interval (CI): 1.47-11.87), whereas skin allergies were negatively associated (OR=0.42; 95% CI: 0.20-0.91). CONCLUSION: Our findings suggest that allergies and AL in children with DS share biological and immune mechanisms. To our knowledge, this is the first study reporting associations between allergies and AL in children with DS.


Assuntos
Síndrome de Down/epidemiologia , Hipersensibilidade/epidemiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Estudos de Casos e Controles , Criança , Feminino , Humanos , Modelos Logísticos , Masculino , México/epidemiologia
13.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1489489

RESUMO

A Contratura de Dupuytren (DC) é uma doença fibroproliferativa caracterizada pela formação de nódulos e cordões fibrosos que se retraem longitudinalmente em direção aos dedos causando à contratura digital que determina o aspecto de mão em garra, sendo por isso citada como diagnóstico diferencial da hanseníase. Sua incidência é maior na raça branca de origem européia, principalmente em adultos do sexo masculino com idade superior a 50 anos. Embora existam evidências do envolvimento genético no aparecimento da DC, até o momento nenhum gene foi associado como fator de risco para a doença.

15.
Cancer Radiother ; 15(6-7): 504-8, 2011 Oct.
Artigo em Francês | MEDLINE | ID: mdl-21880535

RESUMO

The recent advances in medical imaging have profoundly altered the radiotherapy of non-small cell lung cancers (NSCLC). A meta-analysis has confirmed the superiority of FDG PET-CT over CT for initial staging. FDG PET-CT improves the reproducibility of target volume delineation, especially close to the mediastinum or in the presence of atelectasia. Although not formally validated by a randomized trial, the reduction of the mediastinal target volume, by restricting the irradiation to FDG-avid nodes, is widely accepted. The optimal method of delineation still remains to be defined. The role of FDG PET-CT in monitoring tumor response during radiotherapy is under investigation, potentially opening the way to adapting the treatment modalities to tumor radiation sensitivity. Other tracers, such as F-miso (hypoxia), are also under clinical investigation. To avoid excessive delays, the integration of PET-CT in routine practice requires quick access to the imaging equipment, technical support (fusion and image processing) and multidisciplinary delineation of target volumes.


Assuntos
Radioisótopos de Flúor , Fluordesoxiglucose F18 , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/secundário , Ensaios Clínicos como Assunto , Humanos , Neoplasias Pulmonares/radioterapia , Metástase Linfática/diagnóstico por imagem , Mediastino/diagnóstico por imagem , Estadiamento de Neoplasias/métodos , Prognóstico , Fatores de Tempo , Resultado do Tratamento , Carga Tumoral
16.
Q J Nucl Med Mol Imaging ; 55(3): 324-33, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21532544

RESUMO

AIM: We assessed in this study the influence of contrast-enhanced CT (ceCT) on PET/CT interpretation and PET/CT on ceCT interpretation in patients with lymphoma, before and after chemotherapy. METHODS: Fifty patients with Hodgkin disease (N.=17) or non-Hodgkin lymphomas (N.=33) were assessed before and after chemotherapy. PET/CT were performed 60 minutes after injection of FDG. Iopamidol was then injected and followed, 50 seconds later, by another CT. PET images were successively reconstructed using non-enhanced CT (PET-) and ceCT (PET+). Four nuclear physicians rated PET- and PET+ in random order. Three radiologists initially rated ceCT alone and then ceCT along with PET+. RESULTS: Before chemotherapy, global agreement (GA) was 99% (k=0.96) when PET- was compared to PET+. Nine (5%) lesions were discordant, 5 according to PET- and 4 to PET+. After chemotherapy, GA was 99% (k=0.91). Eight (15%) lesions were discordant, 3 according to PET- and 5 to PET+. Before chemotherapy, GA was 97% (k=0.91) when ceCT was compared to ceCT with PET+. Twenty-one (12%) lesions were discordant, 16 when ceCT were analyzed alone and 5 when ceCT was analyzed with PET+. After chemotherapy, GA was 95% (k=0.76). All 30 (35%) discordant lesions were positive according to ceCT alone. A significant difference between the 2 procedures was found in the pelvis and in the groin (P<0.05). CONCLUSION: PET+ did not differ from PET-, before and after chemotherapy. Fewer abnormalities were observed, when ceCT was analyzed with PET+, particularly after chemotherapy, due to residual masses that are better analyzed with functional imaging.


Assuntos
Linfoma/diagnóstico por imagem , Adulto , Idoso , Meios de Contraste , Feminino , Doença de Hodgkin/diagnóstico por imagem , Doença de Hodgkin/tratamento farmacológico , Humanos , Linfoma/tratamento farmacológico , Linfoma não Hodgkin/diagnóstico por imagem , Linfoma não Hodgkin/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Medicina Nuclear , Variações Dependentes do Observador , Tomografia por Emissão de Pósitrons , Interpretação de Imagem Radiográfica Assistida por Computador , Radiologia , Tomografia Computadorizada por Raios X
17.
J Clin Endocrinol Metab ; 96(5): 1352-9, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21389143

RESUMO

PURPOSE: This prospective study evaluated the recurrence rate in 715 patients with differentiated thyroid cancer who had no evidence of persistent disease after total thyroidectomy and lymph node dissection in 94% of them followed up by radioiodine ablation (30-100 mCi) and assessed the predictive value of the initial thyroglobulin (Tg) levels for detecting recurrence, both during levothyroxine (LT4) treatment and after TSH stimulation. PATIENTS AND METHODS: Patients had Tg determinations performed at 3 months on LT4 treatment (Tg1) and at 9-12 months after stimulation by either thyroid hormone withdrawal or recombinant human TSH (Tg2); the Access kit was used (functional sensitivity of 0.11 ng/ml); they had undetectable anti-Tg antibodies. Patients were followed up annually. Predictive values were calculated by comparing Tg levels (Tg1 and Tg2) and the outcome in terms of recurrence. RESULTS: During the median follow-up of 6.2 yr, 32 patients had a recurrence. Assuming a cutoff level for Tg1 at 0.27 ng/ml, Tg1 sensitivity and specificity reached 72 and 86%, respectively, whereas predictive positive and negative values were 20 and 99%, respectively. With a cutoff level for Tg2 at 1.4 ng/ml, sensitivity and specificity reached 78 and 90%, respectively, whereas positive and negative predictive values were 26 and 99%, respectively. CONCLUSION: This large prospective cohort of patients presented a low rate of recurrence. Initial Tg measurements allow to predict long-term recurrence with an excellent specificity. Stimulated Tg determination presented a slightly higher sensitivity than Tg determination on LT4. TSH stimulation may be avoided when Tg measured 3 months after ablation is less than 0.27 ng/ml during LT4 treatment.


Assuntos
Carcinoma Papilar, Variante Folicular/terapia , Neoplasias da Glândula Tireoide/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Autoanticorpos/análise , Carcinoma Papilar, Variante Folicular/epidemiologia , Carcinoma Papilar, Variante Folicular/cirurgia , Estudos de Coortes , Terapia Combinada , Feminino , Seguimentos , Terapia de Reposição Hormonal , Humanos , Radioisótopos do Iodo/uso terapêutico , Excisão de Linfonodo , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Valor Preditivo dos Testes , Estudos Prospectivos , Tireoglobulina/imunologia , Neoplasias da Glândula Tireoide/epidemiologia , Tireoidectomia , Tireotropina/uso terapêutico , Tiroxina/uso terapêutico , Resultado do Tratamento , Adulto Jovem
18.
Gynecol Obstet Fertil ; 38(4): 244-9, 2010 Apr.
Artigo em Francês | MEDLINE | ID: mdl-20359931

RESUMO

OBJECTIVES: Assessment of prognostic value of pretherapeutic (18)F-FDG PET/CT (PET). PATIENTS AND METHODS: Retrospective study of 53 patients with invasive uterine cervix carcinoma. Each patient has been evaluated with pretherapeutic whole-body FDG PET/CT and pelvic MRI. Minimal follow-up lasted for 1 year. On PET/CT, we have visually analyzed metabolism of primary tumor, pelvic and para-aortic lymph nodes in comparison with surrounding structures. We have compared prognostic factors as pretherapeutic haemoglobin rate, FIGO staging, MRI and PET/CT data using Mann-Whitney univariate analysis and Cox multivariate analysis. RESULTS: Para-aortic lymph node abnormal uptake on PET/CT was the only independent predictor of progression-free survival. Pelvic lymph node involvement on PET/CT was the only independent predictor of overall survival. MRI did not provide any additional information. DISCUSSION AND CONCLUSION: Lymph node involvement visually assessed by (18)F-FDG PET/CT was the most significant prognostic factor for overall and progression-free survival.


Assuntos
Adenocarcinoma Mucinoso/diagnóstico por imagem , Carcinoma de Células Escamosas/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Adenocarcinoma Mucinoso/mortalidade , Adenocarcinoma Mucinoso/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Intervalo Livre de Doença , Feminino , Fluordesoxiglucose F18 , Humanos , Linfonodos/diagnóstico por imagem , Metástase Linfática , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Prognóstico , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/patologia
19.
J Synchrotron Radiat ; 16(Pt 6): 864-8, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19844025

RESUMO

The cumulant expansion is one of the most powerful and useful methods for EXAFS data analysis, in which the higher-order cumulants allow to consider deviations from a simple Gaussian distribution. In this work, analytical expressions have been derived to show the effects of neglecting higher-order cumulants in EXAFS analysis by the ratio method. The errors in the best-fitting procedure owing to the omission of the higher-order cumulants, as well as of the coordination number, can be determined.

20.
Phys Med Biol ; 54(22): 6901-16, 2009 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-19864698

RESUMO

An iterative generic algorithm has been developed to compare three thresholding models used to delineate gross tumour volume on (18)F-FDG PET images. 3D volume was extracted and characteristic parameters were measured. Three fitting models using different parameters were studied: model 1 (volume, contrast), model 2 (contrast) and model 3 (SUV). The calibration was performed using a cylindrical phantom filled with hot spheres. To validate the models, two other phantoms were used. The calibration procedure showed a better fitting model for model 1 (R(2) from 0.94 to 1.00) than for model 3 (0.95) and model 2 (0.69). The validation study shows that model 3 yielded large volume measurement errors. Models 1 and 2 gave close results with no significant differences. Model 2 was preferred because it presents less error dispersion and needs fewer characteristic parameters, making it easier to implement. Our results show the importance of developing a generic algorithm to compare the performances of fitting models objectively and to validate results on other phantoms than the ones used during the calibration process to avoid methodological biases.


Assuntos
Algoritmos , Fluordesoxiglucose F18 , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Modelos Biológicos , Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Inteligência Artificial , Simulação por Computador , Limiar Diferencial , Humanos , Reconhecimento Automatizado de Padrão/métodos , Imagens de Fantasmas , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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