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1.
Clin Transl Radiat Oncol ; 44: 100696, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37965060

RESUMO

Background: Elective neck irradiation (ENI) is performed in head and neck cancer patients treated with definitive (chemo)radiotherapy. The aim is to eradicate nodal metastases that are not detectable by pretreatment imaging techniques. It is conceivable that personalized neck irradiation can be performed guided by the results of sentinel lymph node biopsy (SLNB). It is expected that ENI can be omitted to one or both sides of the neck in 9 out of 10 patients, resulting in less radiation side effects with better quality of life. Methods/design: This is a multicenter randomized controlled trial aiming to compare safety and efficacy of treatment with SLNB guided neck irradiation versus standard bilateral ENI in 242 patients with cN0 squamous cell carcinoma of the oropharynx, larynx or hypopharynx for whom bilateral ENI is indicated. Patients randomized to the experimental-arm will undergo SLNB. Based on the histopathologic status of the SLNs, patients will receive no ENI (if all SLNs are negative), unilateral neck irradiation only (if a SLN is positive at one side of the neck) or bilateral neck irradiation (if SLNs are positive at both sides of the neck). Patients randomized to the control arm will not undergo SLNB but will receive standard bilateral ENI. The primary safety endpoint is the number of patients with recurrence in regional lymph nodes within 2 years after treatment. The primary efficacy endpoint is patient reported xerostomia-related quality of life at 6 months after treatment. Discussion: If this trial demonstrates that the experimental treatment is non-inferior to the standard treatment in terms of regional recurrence and is superior in terms of xerostomia-related quality of life, this will become the new standard of care.

2.
Br J Educ Psychol ; 93(2): 545-570, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36693697

RESUMO

BACKGROUND: The reciprocal internal/external frame of reference (RI/E) combines two models of academic self-concept formation, namely the reciprocal effects model (REM) and the internal/external frame of reference (I/E) model. The REM assumes reciprocal relations between achievement and academic self-concept. The I/E model assumes contrast effects between achievement and self-concept across math and verbal domains. The RI/E model can be extended to more school subjects than one math and one verbal domain, and to other motivational constructs. AIMS: We examined an extended RI/E model considering achievement, academic self-concept, and intrinsic value related to math, German and English. SAMPLE: The sample consisted of 1939 German secondary school students. METHODS: The three measurement waves covered Grades 5 to 7. Cross-lagged panel models were used to analyse the data. RESULTS: Within domains, there were reciprocal relations between achievement and academic self-concept but only unidirectional relations between former achievements and later intrinsic values. Across domains, there were significant negative relations between former math achievement and later self-concepts and intrinsic values in German and English, and between former German and English achievements and later self-concept and intrinsic value in math. These findings imply contrast effects across math and verbal domains. The pattern of relations among constructs was found to be generalizable across gender and school tracks and stable across measurement waves. CONCLUSION: The study provides further support for the validity of the RI/E model and its extension to English as another school subject and intrinsic value as another motivational construct.


Assuntos
Instituições Acadêmicas , Autoimagem , Humanos , Motivação , Formação de Conceito
3.
Eur J Nucl Med Mol Imaging ; 49(3): 943-952, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34476551

RESUMO

PURPOSE: MYC gene rearrangements in diffuse large B-cell lymphoma (DLBCL) patients are associated with poor prognosis. Our aim was to compare patterns of 2[18F]fluoro-2-deoxy-D-glucose positron emission tomography computed tomography (PET/CT) response in MYC + and MYC- DLBCL patients. METHODS: Interim PET/CT (I-PET) and end of treatment PET/CT (EoT-PET) scans of 81 MYC + and 129 MYC- DLBCL patients from 2 HOVON trials were reviewed using the Deauville 5-point scale (DS). DS1-3 was regarded as negative and DS4-5 as positive. Standardized uptake values (SUV) and metabolic tumor volume (MTV) were quantified at baseline, I-PET, and EoT-PET. Negative (NPV) and positive predictive values (PPV) were calculated using 2-year overall survival. RESULTS: MYC + DLBCL patients had significantly more positive EoT-PET scans than MYC- patients (32.5 vs 15.7%, p = 0.004). I-PET positivity rates were comparable (28.8 vs 23.8%). In MYC + patients 23.2% of the I-PET negative patients converted to positive at EoT-PET, vs only 2% for the MYC- patients (p = 0.002). Nine (34.6%) MYC + DLBCL showed initially uninvolved localizations at EoT-PET, compared to one (5.3%) MYC- patient. A total of 80.8% of EoT-PET positive MYC + patients showed both increased lesional SUV and MTV compared to I-PET. In MYC- patients, 31.6% showed increased SUV and 42.1% showed increased MTV. NPV of I-PET and EoT-PET was high for both MYC subgroups (81.8-94.1%). PPV was highest at EoT-PET for MYC + patients (61.5%). CONCLUSION: MYC + DLBCL patients demonstrate aberrant PET response patterns compared to MYC- patients with more frequent progression during treatment after I-PET negative assessment and new lesions at sites that were not initially involved. TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION: HOVON-84: EudraCT: 2006-005,174-42, retrospectively registered 01-08-2008. HOVON-130: EudraCT: 2014-002,654-39, registered 26-01-2015.


Assuntos
Linfoma Difuso de Grandes Células B , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Fluordesoxiglucose F18 , Rearranjo Gênico , Humanos , Linfoma Difuso de Grandes Células B/diagnóstico por imagem , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/terapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia por Emissão de Pósitrons , Prognóstico , Estudos Retrospectivos
4.
J Pers Assess ; 104(6): 759-773, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34788168

RESUMO

Conscientiousness is the most important personality predictor of academic achievement. It consists of several lower order facets with differential relations to academic achievement. There is currently no short instrument assessing facets of conscientiousness in the educational context. Therefore, in the present multi-study report, we develop and validate a short-form questionnaire for the assessment of seven Conscientiousness facets, namely Industriousness, Perfectionism, Tidiness, Procrastination Refrainment, Control, Caution, and Task Planning. To this end, we examined multiple representative samples totaling N = 14,604 Grade 9 and 10 students from Luxembourg. The questionnaire was developed by adapting and shortening an existing scale using an exhaustive search algorithm. The algorithm was specified to select the best item combination based on model fit, reliability, and measurement invariance across the German and French language versions. The resulting instrument showed the expected factorial structure. The relations of the facets with personality constructs and academic achievement were in line with theoretical assumptions. Reliability was acceptable for all facets. Measurement invariance across language versions, gender, immigration status and cohort was established. We conclude that the presented questionnaire provides a short measurement of seven facets of Conscientiousness with valid and reliable scores.


Assuntos
Personalidade , Estudantes , Humanos , Reprodutibilidade dos Testes , Inquéritos e Questionários
5.
Am J Intellect Dev Disabil ; 125(2): 125-147, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32058814

RESUMO

Expectancy-value theory (EVT) is a popular framework to understand and improve students' motivation. Unfortunately, limited research has verified whether EVT predictions generalize to students with low levels of cognitive ability. This study relies on Grade 5 and 8 data from 177 students with low levels of cognitive ability and a matched sample of 177 students with average to high cognitive ability from the German "Project for the Analysis of Learning and Achievement in Mathematics." Results showed that students with low levels of cognitive ability were able to differentiate EVT components. Both groups demonstrated a similar downward developmental trend in motivation from early to middle adolescence, and similar relations between EVT components and levels of efforts, self-regulation, and mathematics class grades.


Assuntos
Sucesso Acadêmico , Desenvolvimento do Adolescente/fisiologia , Aptidão/fisiologia , Cognição/fisiologia , Inteligência/fisiologia , Aprendizagem/fisiologia , Matemática , Motivação/fisiologia , Autocontrole , Estudantes , Adolescente , Criança , Feminino , Alemanha , Humanos , Estudos Longitudinais , Masculino , Instituições Acadêmicas
6.
Child Abuse Negl ; 99: 104250, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31835234

RESUMO

BACKGROUND: Findings on whether immigrant students suffer from higher levels of peer victimization have been inconsistent, perhaps due to a blend of measures for personal and ethnic peer victimization. OBJECTIVE: In this study, we investigated personal and ethnic peer victimization using latent profile analyses. The profiles were related to various predictor and outcome variables. PARTICIPANTS AND SETTING: The sample consisted of N = 4367 German elementary school students attending grades 3 and 4. METHODS: The students responded to eight items addressing personal peer victimization and one item addressing ethnic peer victimization. RESULTS: The findings indicated a three-profile solution. In Profile 1, students experienced a combination of personal and ethnic peer victimization; Profile 2 contained students without any victimization experiences; in Profile 3, students experienced personal peer victimization only. Relative to native German-speaking students, non-native German-speaking students had a higher chance to be classified in Profile 1 compared to Profiles 2 and 3. Both profiles of peer victimization (i.e., Profiles 1 and 3) were associated with negative outcomes including higher levels of different types of anxiety and depression, and lower levels of self-esteem and peer self-concept. CONCLUSIONS: Student subgroups of different patterns of peer victimization were found, whereby ethnic peer victimization was blended with personal peer victimization in one subgroup, and personal peer victimization was experienced in a pure form in another subgroup. The two victimization subgroups did not differ with regard to outcomes, but were differentially predicted by students' native language.


Assuntos
Bullying , Etnicidade , Grupo Associado , Ansiedade , Criança , Vítimas de Crime , Feminino , Alemanha , Humanos , Análise de Classes Latentes , Masculino , Autoimagem , Estudantes/psicologia
7.
Br J Educ Psychol ; 89(4): 689-706, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30375653

RESUMO

BACKGROUND: Positive school attitudes defined as students' school liking and school attachment are positively related to many desirable outcomes. Student-teacher relations have often been considered to be an important determinant of school attitudes. AIMS: Students' perceived teacher acceptance was used as an indicator for student-teacher relations. Using a longitudinal data set, we examined the developmental trajectories of school attitudes and perceived teacher acceptance. In addition, we studied the temporal relations between both constructs.. We also examined gender differences in the mean levels, mean level development, and relations of school attitudes and teacher acceptance. SAMPLE: The sample consisted of 2,376 German elementary school students. METHODS: The students rated their school attitudes and perceived teacher acceptance three times across grade levels 3-4. Latent growth curve models were used to examine the developmental trajectories of both constructs. Cross-lagged panel models were used to examine the temporal relations between both constructs. RESULTS: Positive school attitudes and perceived teacher acceptance declined across time. School attitudes and perceived teacher acceptance were positively and reciprocally related across the three waves. Boys and girls did not differ in their temporal relations between school attitudes and perceived teacher acceptance and in the developmental trajectories of both constructs. Girls were found to display higher mean levels of school attitudes and perceived teacher acceptance. CONCLUSIONS: Research and practice should seek for effective means to counteract the decline of students' positive school attitudes and perceived teacher acceptance. Interventions to foster students' school attitudes might benefit from enhancing student-teacher relations, and vice versa.


Assuntos
Atitude , Relações Interpessoais , Professores Escolares , Instituições Acadêmicas , Percepção Social , Estudantes , Criança , Feminino , Humanos , Estudos Longitudinais , Masculino , Fatores Sexuais
8.
Dev Psychol ; 54(2): 263-280, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29172566

RESUMO

Our newly proposed integrated academic self-concept model integrates 3 major theories of academic self-concept formation and developmental perspectives into a unified conceptual and methodological framework. Relations among math self-concept (MSC), school grades, test scores, and school-level contextual effects over 6 years, from the end of primary school through the first 5 years of secondary school (a representative sample of 3,370 German students, 42 secondary schools, 50% male, M age at grade 5 = 11.75) support the (1) internal/external frame of reference model: Math school grades had positive effects on MSC, but the effects of German grades were negative; (2) reciprocal effects (longitudinal panel) model: MSC was predictive of and predicted by math test scores and school grades; (3) big-fish-little-pond effect: The effects on MSC were negative for school-average achievement based on 4 indicators (primary school grades in math and German, school-track prior to the start of secondary school, math test scores in the first year of secondary school). Results for all 3 theoretical models were consistent across the 5 secondary school years: This supports the prediction of developmental equilibrium. This integration highlights the robustness of support over the potentially volatile early to middle adolescent period; the interconnectedness and complementarity of 3 ASC models; their counterbalancing strengths and weaknesses; and new theoretical, developmental, and substantive implications at their intersections. (PsycINFO Database Record


Assuntos
Sucesso Acadêmico , Modelos Psicológicos , Autoimagem , Criança , Feminino , Humanos , Funções Verossimilhança , Estudos Longitudinais , Masculino , Conceitos Matemáticos , Análise Multinível , Psicologia da Criança , Inquéritos e Questionários
9.
Am J Intellect Dev Disabil ; 122(6): 539-560, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29115873

RESUMO

This study examines the development of self-esteem in a sample of 138 Australian adolescents (90 males; 48 females) with cognitive abilities in the lowest 15% (L-CA) and a matched sample of 556 Australian adolescents (312 males; 244 females) with average to high levels of cognitive abilities (A/H-CA). These participants were measured annually (Grade 7 to 12). The findings showed that adolescents with L-CA and A/H-CA experience similar high and stable self-esteem trajectories that present similar relations with key predictors (sex, school usefulness and dislike, parenting, and peer integration). Both groups revealed substantial gender differences showing higher levels of self-esteem for adolescent males remaining relatively stable over time, compared to lower levels among adolescent females which decreased until midadolescence before increasing back.


Assuntos
Desenvolvimento do Adolescente , Aptidão/fisiologia , Deficiência Intelectual/psicologia , Inteligência/fisiologia , Autoimagem , Adolescente , Austrália , Feminino , Humanos , Estudos Longitudinais , Masculino
10.
Dev Psychol ; 53(5): 933-948, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28358538

RESUMO

The present study focuses on political efficacy in terms of students' competence self-perceptions related to the domain of politics. The investigation addresses the mean level development and longitudinal relations to outcome variables including gender differences. Drawing on a sample of N = 2,504 German students, political efficacy, along with meaningful outcome variables (i.e., political information behavior, political knowledge, and interest in politics), was measured at 2 measurement points, once in Grade 7 and once in Grade 10. Students' mean levels of political efficacy increased from the first to the second measurement point, and boys consistently displayed higher levels. Political efficacy demonstrated reciprocal relations to political information behavior and political knowledge, and showed a unidirectional relation to interest in politics across time. The pattern of outcome relations was invariant across gender. This study contributes to research and theory on political socialization in adolescence as it outlines temporal relations among, and gender differences in, facets of political socialization. Therefore, this study also offers new practical insights into effectively facilitating political education in adolescent students. (PsycINFO Database Record


Assuntos
Comportamento do Adolescente/psicologia , Desenvolvimento do Adolescente , Política , Autoimagem , Socialização , Adolescente , Feminino , Alemanha , Humanos , Conhecimento , Masculino , Fatores Sexuais
11.
J Youth Adolesc ; 46(4): 801-825, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27663575

RESUMO

Are internalizing and externalizing behavior problems interrelated via mutually reinforcing relationships (with each behavior leading to increases over time in levels of the other behavior) or mutually suppressing relationships (with each behavior leading to decreases over time in levels of the other behavior)? Past research on the directionality of these relationships has led to ambiguous results, particularly in adolescence. Furthermore, the extent to which prior results will generalize to adolescents with low levels of cognitive abilities remains unknown. This second limit is particularly important, given that these adolescents are known to present higher levels of externalizing and internalizing behaviors than their peers with average-to-high levels of cognitive abilities, and that the mechanisms involved in the reciprocal relationships between these two types of behaviors may differ across both populations. This study examines the directionality of the longitudinal relationships between externalizing and internalizing behavior problems as rated by teachers across three measurement waves (corresponding to Grades 8-10) in matched samples of 138 adolescents (34.78 % girls) with low levels of cognitive abilities and 556 adolescents (44.88 % girls) with average-to-high levels of cognitive abilities. The results showed that the measurement structure was fully equivalent across time periods and groups of adolescents, revealing high levels of developmental stability in both types of problems, and moderately high levels of cross-sectional associations. Levels of both internalizing and externalizing behaviors were higher among adolescents with low levels of cognitive abilities relative to those with average-to-high levels of cognitive abilities. Finally, the predictive analyses revealed negative reciprocal longitudinal relationships (i.e., mutually suppressing relationships) between externalizing and internalizing problems, a result that was replicated within samples of adolescents with low, and average-to-high levels of cognitive ability.


Assuntos
Comportamento do Adolescente/classificação , Cognição , Controle Interno-Externo , Professores Escolares , Adolescente , Comportamento do Adolescente/psicologia , Criança , Estudos Transversais , Mecanismos de Defesa , Feminino , Humanos , Masculino , Instituições Acadêmicas
12.
Ned Tijdschr Geneeskd ; 160: D426, 2016.
Artigo em Holandês | MEDLINE | ID: mdl-27484427

RESUMO

A 42-year-old man with a medical history of liver cirrhosis and portal hypertension was admitted to the hospital because of slowly progressive shortness of breath and hypoxemia. The diagnosis hepatopulmonary syndrome was confirmed by a pulmonary perfusion scan with 99m Tc-albumin. The scan showed a right-left shunt, because the 99m Tc-albumin transited the lungs and appeared in the brain, the thyroid gland, the kidneys and the spleen. The patient received a liver transplantation, which is considered the only definitive treatment.


Assuntos
Dispneia/etiologia , Síndrome Hepatopulmonar/complicações , Síndrome Hepatopulmonar/diagnóstico por imagem , Esforço Físico/fisiologia , Agregado de Albumina Marcado com Tecnécio Tc 99m , Adulto , Dispneia/fisiopatologia , Síndrome Hepatopulmonar/cirurgia , Humanos , Transplante de Fígado , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Masculino , Cintilografia , Compostos Radiofarmacêuticos
13.
Dev Psychol ; 52(8): 1273-90, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27455188

RESUMO

Ever since the classic research of Nicholls (1976) and others, effort has been recognized as a double-edged sword: while it might enhance achievement, it undermines academic self-concept (ASC). However, there has not been a thorough evaluation of the longitudinal reciprocal effects of effort, ASC, and achievement, in the context of modern self-concept theory and statistical methodology. Nor have there been developmental equilibrium tests of whether these effects are consistent across the potentially volatile early-to-middle adolescence. Hence, focusing on mathematics, we evaluate reciprocal effects models (REMs) over the first 4 years of secondary school (grades 5-8), relating effort, achievement (test scores and school grades), ASC, and ASC × Effort interactions for a representative sample of 3,144 German students (Mage = 11.75 years at Wave 1). ASC, effort, and achievement were positively correlated at each wave, and there was a clear pattern of positive reciprocal positive effects among ASC, test scores, and school grades-each contributing to the other, after controlling for the prior effects of all others. There was an asymmetrical pattern of effects for effort that is consistent with the double-edged sword premise: prior school grades had positive effects on subsequent effort, but prior effort had nonsignificant or negative effects on subsequent grades and ASC. However, on the basis of a synergistic application of new theory and methodology, we predicted and found a significant ASC × Effort interaction, such that prior effort had more positive effects on subsequent ASC and school grades when prior ASC was high-thus providing a key to breaking the double-edged sword. (PsycINFO Database Record


Assuntos
Logro , Desenvolvimento Infantil , Conceitos Matemáticos , Autoimagem , Criança , Feminino , Alemanha , Humanos , Controle Interno-Externo , Estudos Longitudinais , Masculino , Modelos Psicológicos , Motivação , Instituições Acadêmicas , Estudantes
14.
Artigo em Inglês | MEDLINE | ID: mdl-26851591

RESUMO

The challenges of producing and distributing the food necessary to feed an anticipated 9 billion people in developed and developing societies by 2050 without destroying Earth's finite soil and water resources present extremely complex problems that lack simple solutions. The ability of modern societies to adequately address these and other food-related problems will require an educated workforce trained not only in traditional food safety, security, and public health, but also in other areas including food production, sustainable practices, and ecosystem health. To help address the need for such an educated workforce, a curricular framework was developed to assist those tasked with designing education and training for future food systems workers. One sentence summary: A curricular framework for education and training in food safety and security was developed that incorporates One Health concepts.


Assuntos
Agricultura/educação , Currículo , Inocuidade dos Alimentos , Abastecimento de Alimentos , Saúde Pública/educação , Animais , Conservação dos Recursos Naturais , Países em Desenvolvimento , Ecossistema , Comunicação Interdisciplinar
15.
Int J Methods Psychiatr Res ; 25(4): 277-288, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-26265387

RESUMO

This paper illustrates a psychometric approach of broad relevance to psychiatric research instruments. Many instruments include indicators related to more than one source of true-score variance due to the: (1) assessment of conceptually adjacent constructs; (2) the presence of a global construct underlying answers to items designed to assess multiple dimensions. Exploratory structural equation modelling (ESEM) is naturally suited to the investigation of the first source, whereas bifactor models are particularly suited to the investigation of the second source. When both sources are present, bifactor-ESEM becomes the model of choice. To illustrate this framework, we use the responses of 1159 adults [655 female, 504 male, mean age (Mage ) = 41.84] who completed the French Version of the Composite Scale of Morningness (CSM). We investigate the factor structure of the CSM, test the relations between CSM factors and body mass index, and verify the measurement invariance of the model across gender and age groups. Copyright © 2015 John Wiley & Sons, Ltd.


Assuntos
Modelos Estatísticos , Psiquiatria/métodos , Psicometria/métodos , Adulto , Ritmo Circadiano/fisiologia , Feminino , Humanos , Masculino
17.
Ann Oncol ; 23(10): 2676-2681, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22776707

RESUMO

BACKGROUND: Hodgkin Lymphoma (HL) is highly curable when treated accurately. The challenge is to cure patients with the minimal risk of long-term complications. For that, optimal initial diagnostics are required to determine the optimal treatment plan. We offer non-academic hospitals in our Regional Comprehensive Cancer Centre network a centralised review of all diagnostic procedures from patients with newly diagnosed HL. We report our experience on concordances and discrepancies between local findings and central review results. PATIENTS AND METHODS: A haematologist and radiation oncologist at the Hodgkin Radboud University Nijmegen Medical Centre outpatient clinic examined all patients with newly diagnosed HL between February 2006 and May 2010. In a multidisciplinary lymphoma conference, diagnostic information is reviewed and treatment advice formulated. Discordant findings in pathology, staging and therapy were recorded as 'minor', no therapeutic consequences or 'major', adapted therapy advice. RESULTS: Altogether, 125 patients were included. Pathology review showed 86% concordance, with 4% major discordance, mainly nodular lymphocyte predominant sub-type. Revision of initial staging was concordant in 77%; however 15% major discordance of which most were upstaged. This resulted in 19% treatment adaption. CONCLUSION: Our findings highlight the discrepancies in interpretation of diagnostic tests. We advocate centralised review process for all newly diagnosed patients with HL.


Assuntos
Doença de Hodgkin/diagnóstico , Equipe de Assistência ao Paciente , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada , Feminino , Doença de Hodgkin/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Radioterapia , Adulto Jovem
18.
Q J Nucl Med Mol Imaging ; 55(5): 521-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22019709

RESUMO

Advances in the field of radiation oncology in the last decade resulted in an increasing number of opportunities to optimize therapy. Increased accuracy to deliver the dose to tumors while sparing normal tissues demands more precise delineation of the tumors. When considering to deliver a boost to more aggressive parts of tumors, intratumoral heterogeneity needs to be assessed accurately. Adaptive radiotherapy demands evaluation of response during the course of radiotherapy, in terms of both volumetric and functional changes. Molecular imaging with fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) has found its way into clinical practice for various indications in head and neck cancer and new applications are under investigation. In this review, an overview is provided of the current status and developments of the use of FDG-PET/CT in radiation oncology, describing the current status in radiation treatment planning, adaptation of therapy and the position compared to other imaging techniques.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Fluordesoxiglucose F18 , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Planejamento da Radioterapia Assistida por Computador , Tomografia Computadorizada por Raios X , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Imagem Multimodal/métodos
19.
Vet Pathol ; 48(3): 593-615, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21097716

RESUMO

California horses incur a bone fragility syndrome manifested by pathologic fractures. This study investigated gross, radiographic, and histologic features of the disorder as well as relationships with silicosis and levels of heavy metals and trace minerals through a postmortem study of 9 affected and 3 unaffected horses. Bones and soft tissues were evaluated grossly and histologically. Bones, lymph nodes, and lung tissue were evaluated radiographically. Tissues were evaluated for silicon levels, intracytoplasmic crystals, heavy metals, and trace minerals. All 9 affected horses had osteoporosis and clinical or subclinical pulmonary disease due to silicosis (8/9) or pneumoconiosis (1/9). All affected horses had radiographic findings consistent with osteopenia and histologic evidence of osteoporosis characterized by osteopenia, numerous resorption cavities, cement lines, and a mosaic lamellar pattern indicative of multiple remodeling events. Silicosis was characterized by widespread pulmonary granuloma formation with fibrosis; variable tracheobronchiolar and mediastinal granulomatous lymphadenitis; intracellular crystals within lung and lymph node macrophages; and pronounced lymph node fibrosis, focal necrosis, and dystrophic calcification. Crystals in lung (6/9) and lymph node (8/9) tissues were identified as cytotoxic silica dioxide polymorphs. Lung and liver tissue from affected horses had elevated levels of elemental silicon. Osteoporosis was highly correlated (r = 0.8, P < .01) with silicosis. No abnormalities in heavy metal or trace minerals were detected. This evaluation indicated that horses with bone fragility disorder have systemic osteoporosis associated with fibrosing pulmonary silicosis. The etiopathogenesis of the bone fragility syndrome is unknown; however, this study provides circumstantial evidence for a silicate associated osteoporosis.


Assuntos
Doenças Ósseas Metabólicas/veterinária , Doenças dos Cavalos/patologia , Osteoporose/veterinária , Silicose/veterinária , Animais , Doenças Ósseas Metabólicas/complicações , Doenças Ósseas Metabólicas/epidemiologia , Doenças Ósseas Metabólicas/patologia , Osso e Ossos/patologia , California/epidemiologia , Feminino , Doenças dos Cavalos/epidemiologia , Doenças dos Cavalos/etiologia , Cavalos , Pulmão/química , Pulmão/patologia , Linfonodos/patologia , Masculino , Osteoporose/epidemiologia , Osteoporose/etiologia , Osteoporose/patologia , Silício/química , Silicose/epidemiologia , Silicose/etiologia , Silicose/patologia
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