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1.
NMR Biomed ; 35(5): e4653, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34816501

RESUMO

Dynamic susceptibility contrast (DSC) MRI is clinically used to measure brain perfusion by monitoring the dynamic passage of a bolus of contrast agent through the brain. For quantitative analysis of the DSC images, the arterial input function is required. It is known that the original assumption of a linear relation between the R2(*) relaxation and the arterial contrast agent concentration is invalid, although the exact relation is as of yet unknown. Studying this relation in vitro is time-consuming, because of the widespread variations in field strengths, MRI sequences, contrast agents, and physiological conditions. This study aims to simulate the R2(*) versus contrast concentration relation under varying physiological and technical conditions using an adapted version of an open-source simulation tool. The approach was validated with previously acquired data in human whole blood at 1.5 T by means of a gradient-echo sequence (proof-of-concept). Subsequently, the impact of hematocrit, field strength, and oxygen saturation on this relation was studied for both gradient-echo and spin-echo sequences. The results show that for both gradient-echo and spin-echo sequences, the relaxivity increases with hematocrit and field strength, while the hematocrit dependency was nonlinear for both types of MRI sequences. By contrast, oxygen saturation has only a minor effect. In conclusion, the simulation setup has proven to be an efficient method to rapidly calibrate and estimate the relation between R2(*) and gadolinium concentration in whole blood. This knowledge will be useful in future clinical work to more accurately retrieve quantitative information on brain perfusion.


Assuntos
Meios de Contraste , Gadolínio DTPA , Hematócrito , Humanos , Campos Magnéticos , Imageamento por Ressonância Magnética/métodos
2.
Support Care Cancer ; 30(7): 6093-6102, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35416504

RESUMO

PURPOSE: Childhood brain tumor survivors (CBTS) are at risk of becoming overweight, which has been shown to be associated with hypothalamic-pituitary (HP) dysfunction during follow-up. Body mass index (BMI) at diagnosis is related to BMI at follow-up. It is uncertain, however, whether aberrant BMI at brain tumor diagnosis reflects early hypothalamic dysfunction or rather reflects genetic and sociodemographic characteristics. We aimed to examine whether BMI at childhood brain tumor diagnosis is associated with HP dysfunction at diagnosis or its development during follow-up. METHODS: The association of BMI at diagnosis of a childhood brain tumor to HP dysfunction at diagnosis or during follow-up was examined in a Dutch cohort of 685 CBTS, excluding children with craniopharyngioma or a pituitary tumor. Individual patient data were retrospectively extracted from patient charts. RESULTS: Of 685 CTBS, 4.7% were underweight, 14.2% were overweight, and 3.8% were obese at diagnosis. Being overweight or obese at diagnosis was not associated with anterior pituitary deficiency or diabetes insipidus at diagnosis or during follow-up. In children with suprasellar tumors, being obese at diagnosis was associated with central precocious puberty. CONCLUSION: Overweight or obesity at diagnosis of a childhood brain tumor seems not to be associated with pituitary deficiencies. These results suggest that genetics and lifestyle may be more important etiologic factors for higher BMI at diagnosis in these children than hypothalamic dysfunction. To improve the long-term outcome of CBTS with regards to overweight and obesity, more attention should be given to lifestyle already at the time of brain tumor treatment.


Assuntos
Neoplasias Encefálicas , Doenças Hipotalâmicas , Índice de Massa Corporal , Neoplasias Encefálicas/complicações , Criança , Seguimentos , Humanos , Doenças Hipotalâmicas/diagnóstico , Doenças Hipotalâmicas/epidemiologia , Doenças Hipotalâmicas/etiologia , Estilo de Vida , Obesidade/complicações , Obesidade/epidemiologia , Sobrepeso , Estudos Retrospectivos , Fatores de Risco
3.
J Med Internet Res ; 24(12): e40370, 2022 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-36382349

RESUMO

BACKGROUND: In the second stage of the Electronic Health Record Sharing System (eHRSS) development, a mobile app (eHealth app) was launched to further enhance collaborative care among the public sector, the private sector, the community, and the caregivers. OBJECTIVE: This study aims to investigate the factors associated with the downloading and utilization of the app, as well as the awareness, perception, and future improvement of the app. METHODS: We collected 2110 surveys; respondents were stratified into 3 groups according to their status of enrollment in the eHRSS. The primary outcome measure was the downloading and acceptance of the eHealth app. We collected the data on social economics factors, variables of the Technology Acceptance Model and Theory of Planned Behavior. Any factors identified as significant in the univariate analysis (P<.20) will be included in a subsequent multivariable regression analysis model. All P values ≤.05 will be considered statistically significant in multiple logistic regression analysis. The structural equation modeling was performed to identify interactions among the variables. RESULTS: The respondents had an overall high satisfaction rate and a positive attitude toward continuing to adopt and recommend the app. However, the satisfaction rate among respondents who have downloaded but not adopted the app was relatively lower, and few of them perceived that the downloading and acceptance processes are difficult. A high proportion of current users expressed a positive attitude about continuing to adopt and recommend the app to friends, colleagues, and family members. The behavioral intention strongly predicted the acceptance of the eHealth app (ß=.89; P<.001). Attitude (ß=.30; P<.001) and perceived norm; ß=.37; P<.001) played important roles in determining behavioral intention, which could predict the downloading and acceptance of the eHealth app (ß=.14; P<.001). CONCLUSIONS: Despite the high satisfaction rate among the respondents, privacy concerns and perceived difficulties in adopting the app were the major challenges of promoting eHealth. Further promotion could be made through doctors and publicity. For future improvement, comprehensive health records and tailored health information should be included.


Assuntos
Aplicativos Móveis , Telemedicina , Humanos , Registros Eletrônicos de Saúde , Intenção , Inquéritos e Questionários
4.
Genet Med ; 23(3): 443-450, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33190143

RESUMO

PURPOSE: The percentage of a maternal cell-free DNA (cfDNA) sample that is fetal-derived (the fetal fraction; FF) is a key driver of the sensitivity and specificity of noninvasive prenatal screening (NIPS). On certain NIPS platforms, >20% of women with high body mass index (and >5% overall) receive a test failure due to low FF (<4%). METHODS: A scalable fetal fraction amplification (FFA) technology was analytically validated on 1264 samples undergoing whole-genome sequencing (WGS)-based NIPS. All samples were tested with and without FFA. RESULTS: Zero samples had FF < 4% when screened with FFA, whereas 1 in 25 of these same patients had FF < 4% without FFA. The average increase in FF was 3.9-fold for samples with low FF (2.3-fold overall) and 99.8% had higher FF with FFA. For all abnormalities screened on NIPS, z-scores increased 2.2-fold on average in positive samples and remained unchanged in negative samples, powering an increase in NIPS sensitivity and specificity. CONCLUSION: FFA transforms low-FF samples into high-FF samples. By combining FFA with WGS-based NIPS, a single round of NIPS can provide nearly all women with confident results about the broad range of potential fetal chromosomal abnormalities across the genome.


Assuntos
Ácidos Nucleicos Livres , Teste Pré-Natal não Invasivo , Aneuploidia , Ácidos Nucleicos Livres/genética , Aberrações Cromossômicas , Feminino , Feto , Humanos , Gravidez , Cuidado Pré-Natal , Diagnóstico Pré-Natal
5.
Phys Rev Lett ; 126(10): 106001, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33784165

RESUMO

Extreme pressures and temperatures are known to drastically affect the chemistry of iron oxides, resulting in numerous compounds forming homologous series nFeOmFe_{2}O_{3} and the appearance of FeO_{2}. Here, based on the results of in situ single-crystal x-ray diffraction, Mössbauer spectroscopy, x-ray absorption spectroscopy, and density-functional theory+dynamical mean-field theory calculations, we demonstrate that iron in high-pressure cubic FeO_{2} and isostructural FeO_{2}H_{0.5} is ferric (Fe^{3+}), and oxygen has a formal valence less than 2. Reduction of oxygen valence from 2, common for oxides, down to 1.5 can be explained by a formation of a localized hole at oxygen sites.

6.
Conserv Biol ; 35(4): 1086-1097, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33244774

RESUMO

Decades of research and policy interventions on biodiversity have insufficiently addressed the dual issues of biodiversity degradation and social justice. New approaches are therefore needed. We devised a research and action agenda that calls for a collective task of revisiting biodiversity toward the goal of sustaining diverse and just futures for life on Earth. Revisiting biodiversity involves critically reflecting on past and present research, policy, and practice concerning biodiversity to inspire creative thinking about the future. The agenda was developed through a 2-year dialogue process that involved close to 300 experts from diverse disciplines and locations. This process was informed by social science insights that show biodiversity research and action is underpinned by choices about how problems are conceptualized. Recognizing knowledge, action, and ethics as inseparable, we synthesized a set of principles that help navigate the task of revisiting biodiversity. The agenda articulates 4 thematic areas for future research. First, researchers need to revisit biodiversity narratives by challenging conceptualizations that exclude diversity and entrench the separation of humans, cultures, economies, and societies from nature. Second, researchers should focus on the relationships between the Anthropocene, biodiversity, and culture by considering humanity and biodiversity as tied together in specific contexts. Third, researchers should focus on nature and economies by better accounting for the interacting structures of economic and financial systems as core drivers of biodiversity loss. Finally, researchers should enable transformative biodiversity research and action by reconfiguring relationships between human and nonhuman communities in and through science, policy, and practice. Revisiting biodiversity necessitates a renewed focus on dialogue among biodiversity communities and beyond that critically reflects on the past to channel research and action toward fostering just and diverse futures for human and nonhuman life on Earth.


Una Agenda para la Investigación y la Acción hacia un Futuro Diverso y Justo para la Vida sobre la Tierra Resumen Las décadas de investigación e intervenciones políticas sobre la biodiversidad han tratado significativamente los temas de la degradación de la biodiversidad y la justicia social. Debido a esto, se requieren nuevas estrategias. Diseñamos una agenda de investigación y acción que llama a la labor colectiva de revisar la biodiversidad hacia el objetivo de sustentar un futuro diverso y justo para la vida sobre la Tierra. Cuando se revisa la biodiversidad, se requiere de una reflexión crítica sobre las investigaciones, políticas y prácticas presentes y pasadas sobre la biodiversidad para inspirar un pensamiento creativo acerca del futuro. Desarrollamos la agenda por medio de un proceso de diálogo de dos años que involucró a casi 300 expertos de diversas disciplinas y localidades. Este proceso estuvo orientado por el conocimiento de las ciencias sociales que muestra cómo la investigación y la acción para la biodiversidad están sostenidas por las opciones de cómo están conceptualizados los problemas. Reconocimos al conocimiento, la acción y la ética como inseparables y sintetizamos un conjunto de principios que ayuda a navegar la labor de revisar la biodiversidad. La agenda articula cuatro áreas temáticas para la investigación en el futuro. Primero, los investigadores necesitan revisar las narrativas de la biodiversidad mediante el cuestionamiento de las conceptualizaciones que excluyen a la diversidad y consolidan la separación entre humanos, culturas, economías y sociedades y la naturaleza. Segundo, los investigadores deberían enfocarse en las relaciones entre el antropoceno, la biodiversidad y la cultura al considerar a la humanidad y la biodiversidad como interconectadas en contextos específicos. Tercero, los investigadores deberían enfocarse en la naturaleza y las economías al tener en mejor cuenta la interacción de las estructuras de los sistemas económico y financiero como conductores nucleares de la pérdida de la biodiversidad. Finalmente, los investigadores deberían permitir la investigación y acción transformadoras de la biodiversidad al reconfigurar las relaciones entre las comunidades humanas y no humanas dentro y a través de la ciencia, la política y la práctica. La revisión de la biodiversidad necesita de un enfoque renovado sobre el diálogo entre las comunidades de la biodiversidad y más allá, que reflexione críticamente sobre el pasado para canalizar a la investigación y acción hacia el fomento del futuro justo y diverso para la vida humana y no humana sobre la Tierra.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Previsões , Humanos , Justiça Social
7.
Magn Reson Med ; 79(3): 1314-1324, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28585234

RESUMO

PURPOSE: To evaluate a prescan-based radiofrequency phase-correction strategy for unbalanced pseudo-continuous arterial spin labeling (pCASL) at 9.4 T in vivo and to test its robustness toward suboptimal shim conditions. METHODS: Label and control interpulse phases were optimized separately by means of two prescans in rats. The mean perfusion as well as the interhemispherical symmetry were measured for several phase combinations (optimized versus theoretical phases) to evaluate the correction quality. Interpulse phases were also optimized under degraded shim conditions (i.e., up to four times the study shim values) to test the strategy's robustness. RESULTS: For all tested shim conditions, the full arterial spin labeling (ASL) signal could be restored. Without any correction, the relative ASL signal was 1.4 ± 1.7%. It increased to 3.6 ± 1.4% with an optimized label phase and to 5.3 ± 1.2% with optimized label and control phases. Moreover, asymmetry between brain hemispheres, which could be as high as 100% without phase optimization, was dramatically reduced to 1 ± 3% when applying optimized label and control phases. CONCLUSIONS: Pseudo-continuous ASL at high magnetic field is very sensitive to shim conditions. Label and control radiofrequency phase optimization based on prescans robustly maximizes the ASL signal obtained with unbalanced pCASL and minimizes the asymmetry between hemispheres. Magn Reson Med 79:1314-1324, 2018. © 2017 International Society for Magnetic Resonance in Medicine.


Assuntos
Angiografia por Ressonância Magnética/métodos , Marcadores de Spin , Algoritmos , Animais , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Masculino , Ratos , Ratos Sprague-Dawley
8.
Clin Chem ; 64(7): 1063-1073, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29760218

RESUMO

BACKGROUND: By identifying pathogenic variants across hundreds of genes, expanded carrier screening (ECS) enables prospective parents to assess the risk of transmitting an autosomal recessive or X-linked condition. Detection of at-risk couples depends on the number of conditions tested, the prevalence of the respective diseases, and the screen's analytical sensitivity for identifying disease-causing variants. Disease-level analytical sensitivity is often <100% in ECS tests because copy number variants (CNVs) are typically not interrogated because of their technical complexity. METHODS: We present an analytical validation and preliminary clinical characterization of a 235-gene sequencing-based ECS with full coverage across coding regions, targeted assessment of pathogenic noncoding variants, panel-wide CNV calling, and specialized assays for technically challenging genes. Next-generation sequencing, customized bioinformatics, and expert manual call review were used to identify single-nucleotide variants, short insertions and deletions, and CNVs for all genes except FMR1 and those whose low disease incidence or high technical complexity precluded novel variant identification or interpretation. RESULTS: Screening of 36859 patients' blood or saliva samples revealed the substantial impact on fetal disease-risk detection attributable to novel CNVs (9.19% of risk) and technically challenging conditions (20.2% of risk), such as congenital adrenal hyperplasia. Of the 7498 couples screened, 335 were identified as at risk for an affected pregnancy, underscoring the clinical importance of the test. Validation of our ECS demonstrated >99% analytical sensitivity and >99% analytical specificity. CONCLUSIONS: Validated high-fidelity identification of different variant types-especially for diseases with complicated molecular genetics-maximizes at-risk couple detection.


Assuntos
Variações do Número de Cópias de DNA , Éxons , Triagem de Portadores Genéticos , Estudos de Coortes , Humanos , Mutação INDEL , Polimorfismo de Nucleotídeo Único
9.
BMC Med Genet ; 19(1): 176, 2018 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-30268105

RESUMO

BACKGROUND: Hereditary cancer screening (HCS) for germline variants in the 3' exons of PMS2, a mismatch repair gene implicated in Lynch syndrome, is technically challenging due to homology with its pseudogene PMS2CL. Sequences of PMS2 and PMS2CL are so similar that next-generation sequencing (NGS) of short fragments-common practice in multigene HCS panels-may identify the presence of a variant but fail to disambiguate whether its origin is the gene or the pseudogene. Molecular approaches utilizing longer DNA fragments, such as long-range PCR (LR-PCR), can definitively localize variants in PMS2, yet applying such testing to all samples can have logistical and economic drawbacks. METHODS: To address these drawbacks, we propose and characterize a reflex workflow for variant discovery in the 3' exons of PMS2. We cataloged the natural variation in PMS2 and PMS2CL in 707 samples and designed hybrid-capture probes to enrich the gene and pseudogene with equal efficiency. For PMS2 exon 11, NGS reads were aligned, filtered using gene-specific variants, and subject to standard diploid variant calling. For PMS2 exons 12-15, the NGS reads were permissively aligned to PMS2, and variant calling was performed with the expectation of observing four alleles (i.e., tetraploid calling). In this reflex workflow, short-read NGS identifies potentially reportable variants that are then subject to disambiguation via LR-PCR-based testing. RESULTS: Applying short-read NGS screening to 299 HCS samples and cell lines demonstrated >99% analytical sensitivity and >99% analytical specificity for single-nucleotide variants (SNVs) and short insertions and deletions (indels), as well as >96% analytical sensitivity and >99% analytical specificity for copy-number variants. Importantly, 92% of samples had resolved genotypes from short-read NGS alone, with the remaining 8% requiring LR-PCR reflex. CONCLUSION: Our reflex workflow mitigates the challenges of screening in PMS2 and serves as a guide for clinical laboratories performing multigene HCS. To facilitate future exploration and testing of PMS2 variants, we share the raw and processed LR-PCR data from commercially available cell lines, as well as variant frequencies from a diverse patient cohort.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Detecção Precoce de Câncer/métodos , Endonuclease PMS2 de Reparo de Erro de Pareamento/genética , Proteínas de Neoplasias/genética , Reação em Cadeia da Polimerase/métodos , Pseudogenes , Alelos , Linhagem Celular Tumoral , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Neoplasias Colorretais Hereditárias sem Polipose/metabolismo , Detecção Precoce de Câncer/instrumentação , Éxons , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Endonuclease PMS2 de Reparo de Erro de Pareamento/análise , Endonuclease PMS2 de Reparo de Erro de Pareamento/metabolismo , Proteínas de Neoplasias/análise , Proteínas de Neoplasias/metabolismo , Reação em Cadeia da Polimerase/normas , Sensibilidade e Especificidade
10.
J Viral Hepat ; 25(8): 920-929, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29532619

RESUMO

It remains unclear whether hepatitis B virus (HBV) infection may modify the severity of viral steatosis in patients coinfected with chronic hepatitis C virus (HCV). We examined the influence of coinfection with HBV on prevalence of steatosis in chronic hepatitis C in a multi-centre cohort of HBV-HCV subjects, and by performing a systematic review and meta-analysis of the literature. We centrally and blindly assessed steatosis prevalence and severity in a cohort of HBV-HCV coinfected subjects compared to HCV and HBV monoinfected controls and we performed a systematic review of studies addressing the prevalence of steatosis in HBV-HCV subjects compared to HCV controls. In the clinical cohort, we included 85 HBV-HCV, 69 HBV and 112 HCV subjects from 16 international centres. There was no significant difference in steatosis prevalence between the HBV-HCV and the HCV groups (33% vs 45%, P = .11). In subgroup analysis, lean HBV-HCV subjects with detectable HBV DNA had less steatosis than lean HCV subjects matched for HCV viremia (15% vs 45%, P = .02). Our literature search identified 5 additional studies included in a systematic review. Overall, prevalence of steatosis > 5% was similar in HBV-HCV infection compared to HCV (pooled odds ratio [OR] 0.91, 95% CI 0.53-1.6) although there was significant heterogeneity (I2 69%, P = .007). In conclusion, although the prevalence of steatosis is similar in HBV-HCV compared to HCV subjects, our analysis suggests that there may be an inhibitory effect of HCV-induced steatogenesis by HBV in certain subgroups of patients.


Assuntos
Coinfecção/complicações , Fígado Gorduroso/epidemiologia , Fígado Gorduroso/patologia , Hepatite B Crônica/complicações , Hepatite C Crônica/complicações , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos
11.
Magn Reson Med ; 77(4): 1656-1664, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27136322

RESUMO

PURPOSE: Arterial spin labeling (ASL) may provide quantitative maps of cerebral blood flow (CBF). Because labeled water exchanges with tissue water, this study evaluates the influence of tissue T1 on CBF quantification using ASL. METHODS: To locally modify T1 , a low dose of manganese (Mn) was intracerebrally injected in one hemisphere of 19 rats (cortex or striatum). Tissue T1 and CBF were mapped using inversion recovery and continuous ASL experiments at 4.7T. RESULTS: Mn reduced the tissue T1 by more than 30% but had little impact on other tissue properties as assessed via dynamic susceptibility and diffusion MRI. Using a single-compartment model, the use of a single tissue T1 value yielded a mean relative ipsilateral (Mn-injected) to contralateral (noninjected) CBF difference of -34% in cortex and -22% in striatum tissue. With a T1 map, these values became -7% and +8%, respectively. CONCLUSION: A low dose of Mn reduces the tissue T1 without modifying CBF. Heterogeneous T1 impacts the ASL estimate of CBF in a region-dependent way. In animals, and when T1 modifications exceed the accuracy with which the tissue T1 can be determined, an estimate of tissue T1 should be obtained when quantifying CBF with an ASL technique. Magn Reson Med 77:1656-1664, 2017. © 2016 International Society for Magnetic Resonance in Medicine.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Circulação Cerebrovascular/fisiologia , Angiografia por Ressonância Magnética/métodos , Manganês/administração & dosagem , Animais , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Encéfalo/irrigação sanguínea , Masculino , Ratos , Ratos Wistar , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Marcadores de Spin
12.
Acta Oncol ; 56(3): 479-483, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28105885

RESUMO

BACKGROUND: Denosumab is a relatively new treatment option for patients with giant-cell tumor of bone (GCTB). The purpose of this study was to report the results for patients treated in Norway. MATERIALS AND METHODS: Patients treated with denosumab for GCTB were identified from the clinical databases at the Norwegian sarcoma reference centers. Data were retrieved from the clinical databases and supplemented by retrospective review of patient records. Denosumab was given as a subcutaneous injection every 4 weeks with loading doses on day 8 and 15 in cycle 1. RESULTS: Eighteen patients treated with denosumab for GCTB were identified. Denosumab was given for recurrent disease in seven cases and as first-line treatment in 11 patients, of which 6 received therapy as part of a neoadjuvant/adjuvant strategy and 5 for surgically unsalvageable primary tumor. Ten of 12 patients with unresectable disease are still on denosumab without progression with median treatment duration of 41 months (range 18-60). Two patients discontinued treatment due to osteonecrosis of the jaw and reduced compliance, respectively. In the adjuvant group, four patients experienced disease recurrence after stopping denosumab. In three of six patients, the extent of surgery was reduced due to neoadjuvant therapy. Seventeen of 18 patients underwent response evaluation with 18F-FDG PET/CT at median 4.7 weeks from starting denosumab. Median baseline SUVmax was 11.0 and median SUVmax at evaluation was 4.9 (p < 0.001). CONCLUSIONS: In a nationwide GCTB patient cohort, denosumab was an effective agent and durable responses were observed. Our results do not support the use of adjuvant therapy in routine clinical practice. 18F-FDG PET/CT could be a valuable tool for early response evaluation.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Denosumab/uso terapêutico , Tumor de Células Gigantes do Osso/tratamento farmacológico , Adolescente , Adulto , Neoplasias Ósseas/epidemiologia , Bases de Dados Factuais , Feminino , Tumor de Células Gigantes do Osso/epidemiologia , Humanos , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Noruega/epidemiologia , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
13.
J Pathol ; 238(1): 120-33, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26466547

RESUMO

In osteosarcoma, a primary mesenchymal bone cancer occurring predominantly in younger patients, invasive tumour growth leads to extensive bone destruction. This process is insufficiently understood, cannot be efficiently counteracted and calls for novel means of treatment. The endocytic collagen receptor, uPARAP/Endo180, is expressed on various mesenchymal cell types and is involved in bone matrix turnover during normal bone growth. Human osteosarcoma specimens showed strong expression of this receptor on tumour cells, along with the collagenolytic metalloprotease, MT1-MMP. In advanced tumours with ongoing bone degeneration, sarcoma cells positive for these proteins formed a contiguous layer aligned with the degradation zones. Remarkably, osteoclasts were scarce or absent from these regions and quantitative analysis revealed that this scarcity marked a strong contrast between osteosarcoma and bone metastases of carcinoma origin. This opened the possibility that sarcoma cells might directly mediate bone degeneration. To examine this question, we utilized a syngeneic, osteolytic bone tumour model with transplanted NCTC-2472 sarcoma cells in mice. When analysed in vitro, these cells were capable of degrading the protein component of surface-labelled bone slices in a process dependent on MMP activity and uPARAP/Endo180. Systemic treatment of the sarcoma-inoculated mice with a mouse monoclonal antibody that blocks murine uPARAP/Endo180 led to a strong reduction of bone destruction. Our findings identify sarcoma cell-resident uPARAP/Endo180 as a central player in the bone degeneration of advanced tumours, possibly following an osteoclast-mediated attack on bone in the early tumour stage. This points to uPARAP/Endo180 as a promising therapeutic target in osteosarcoma, with particular prospects for improved neoadjuvant therapy.


Assuntos
Neoplasias Ósseas/patologia , Osteólise/metabolismo , Osteossarcoma/patologia , Receptores Mitogênicos/metabolismo , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Invasividade Neoplásica , Osteoclastos/patologia , Osteólise/etiologia , Osteólise/patologia
14.
J Acoust Soc Am ; 141(4): 2501, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28464623

RESUMO

The efficient measurement of the threshold and slope of the psychometric function (PF) is an important objective in psychoacoustics. This paper proposes a procedure that combines a Bayesian estimate of the PF with either a look one-ahead or a look two-ahead method of selecting the next stimulus presentation. The procedure differs from previously proposed algorithms in two respects: (i) it does not require the range of possible PF parameters to be specified in advance and (ii) the sequence of probe signal-to-noise ratios optimizes the threshold and slope estimates at a performance level, ϕ, that can be chosen by the experimenter. Simulation results show that the proposed procedure is robust and that the estimates of both threshold and slope have a consistently low bias. Over a wide range of listener PF parameters, the root-mean-square errors after 50 trials were ∼1.2 dB in threshold and 0.14 in log-slope. It was found that the performance differences between the look one-ahead and look two-ahead methods were negligible and that an entropy-based criterion for selecting the next stimulus was preferred to a variance-based criterion.


Assuntos
Psicoacústica , Percepção da Fala , Teste do Limiar de Recepção da Fala/métodos , Estimulação Acústica , Algoritmos , Teorema de Bayes , Simulação por Computador , Humanos , Método de Monte Carlo , Inteligibilidade da Fala
15.
Eur J Nucl Med Mol Imaging ; 42(5): 706-15, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25512056

RESUMO

PURPOSE: Treatment with (131)I-MIBG is associated with significant thyroid damage. This study was undertaken to investigate the long-term efficacy of current thyroid prophylaxis, to explore the relationship between thyroid dysfunction and thyroid volume after exposure to (131)I-MIBG and to evaluate the possible negative effects of (131)I(-) on the parathyroid glands. METHODS: Of 81 long-term surviving patients with neuroblastoma treated with (131)I-MIBG during the period 1999-2012, 24 were finally evaluated. Patients received thyroxine (T4), methimazole and potassium iodide as thyroid protection. In all patients (para)thyroid function was evaluated and ultrasound investigation of the (para)thyroid gland(s) was performed. Thyroid dysfunction was defined as a plasma thyrotropin concentration >5.0 mU/L (thyrotropin elevation, TE) or as the use of T4 at the time of follow-up. Hyperparathyroidism was defined as a serum calcium concentration above the age-related reference range in combination with an inappropriately high parathyroid hormone level. RESULTS: At a median follow-up of 9.0 years after (131)I-MIBG treatment, thyroid disorders were seen in 12 patients (50 %; 9 with TE, 5 with a thyroid nodule and 1 patient was subsequently diagnosed with differentiated thyroid carcinoma). No significant risk factors for the occurrence of thyroid damage could be identified. In 14 of 21 patients (67 %) in whom thyroid volume could be determined, the volume was considered small (<-2SD) for age and gender. Patients treated with T4 at the time of follow-up had significantly smaller thyroid volumes for age than patients without T4 treatment (p = 0.014). None of the patients was diagnosed with hyperparathyroidism. CONCLUSION: Thyroid protection during treatment with (131)I-MIBG needs attention and must be further improved, as thyroid disorders are still frequently seen despite current thyroid prophylaxis. Reduced thyroid volume in neuroblastoma survivors may be related to previous (131)I-MIBG therapy or current T4 treatment. No deleterious effects of (131)I-MIBG on the parathyroid glands could be found.


Assuntos
3-Iodobenzilguanidina/efeitos adversos , Hipotireoidismo/prevenção & controle , Neoplasias Induzidas por Radiação/prevenção & controle , Neuroblastoma/radioterapia , Compostos Radiofarmacêuticos/efeitos adversos , Radioterapia/efeitos adversos , Neoplasias da Glândula Tireoide/prevenção & controle , 3-Iodobenzilguanidina/uso terapêutico , Criança , Pré-Escolar , Feminino , Humanos , Hipotireoidismo/etiologia , Lactente , Masculino , Neoplasias Induzidas por Radiação/etiologia , Compostos Radiofarmacêuticos/uso terapêutico , Neoplasias da Glândula Tireoide/etiologia
16.
Br J Psychiatry ; 207(5): 377-84, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26527664

RESUMO

BACKGROUND: Most research on interventions to counter stigma and discrimination has focused on short-term outcomes and has been conducted in high-income settings. AIMS: To synthesise what is known globally about effective interventions to reduce mental illness-based stigma and discrimination, in relation first to effectiveness in the medium and long term (minimum 4 weeks), and second to interventions in low- and middle-income countries (LMICs). METHOD: We searched six databases from 1980 to 2013 and conducted a multi-language Google search for quantitative studies addressing the research questions. Effect sizes were calculated from eligible studies where possible, and narrative syntheses conducted. Subgroup analysis compared interventions with and without social contact. RESULTS: Eighty studies (n = 422 653) were included in the review. For studies with medium or long-term follow-up (72, of which 21 had calculable effect sizes) median standardised mean differences were 0.54 for knowledge and -0.26 for stigmatising attitudes. Those containing social contact (direct or indirect) were not more effective than those without. The 11 LMIC studies were all from middle-income countries. Effect sizes were rarely calculable for behavioural outcomes or in LMIC studies. CONCLUSIONS: There is modest evidence for the effectiveness of anti-stigma interventions beyond 4 weeks follow-up in terms of increasing knowledge and reducing stigmatising attitudes. Evidence does not support the view that social contact is the more effective type of intervention for improving attitudes in the medium to long term. Methodologically strong research is needed on which to base decisions on investment in stigma-reducing interventions.


Assuntos
Transtornos Mentais/terapia , Saúde Mental/normas , Discriminação Social , Estigma Social , Humanos , Pobreza , Ensaios Clínicos Controlados Aleatórios como Assunto
17.
Psychol Med ; 45(10): 2013-22, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25678059

RESUMO

BACKGROUND: Suicide is a major global public health issue. Mental illness is a risk factor for suicide, but as many individuals with a diagnosed mental health problem do not experience suicidal ideation or attempt suicide, other individual and societal factors must be considered. Mental illness-related discrimination is one potential risk factor. METHOD: Using mixed methods, the influence of discrimination on suicidality amongst 194 individuals diagnosed with depression, bipolar or schizophrenia spectrum disorders was investigated. Qualitative interviews with a sub-sample of 58 individuals who reported a link between experience of discrimination and suicidality were analysed using framework analysis. Quantitative methods were used to examine the model derived from qualitative analyses. RESULTS: Results indicate that the experience of discrimination led 38% of the overall sample of 194 participants, to suicidal feelings and 20% reported that it contributed to making a suicide attempt. The qualitative model derived from interviews with a sub-sample of 58 participants suggested that the experience of discrimination is experienced as a stressor that exceeds coping resources, leading to a negative self-image and a perception of decreased supportive networks/social structure. The anticipation of further negative events and treatment, and the perception of a lack of supportive networks led individuals in this study to feelings of hopelessness and suicidality. Quantitative analyses provided support for the model. CONCLUSIONS: These data suggest that both psychological therapies aimed at improving coping skills and population-level anti-stigma interventions that reduce the occurrence of discrimination may provide some protection against suicide amongst individuals with mental health problems.


Assuntos
Transtornos Mentais/psicologia , Discriminação Social/psicologia , Ideação Suicida , Tentativa de Suicídio/psicologia , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Relações Interpessoais , Entrevistas como Assunto , Masculino , Saúde Mental , Pessoa de Meia-Idade , Fatores de Risco , Autoimagem , Tentativa de Suicídio/estatística & dados numéricos , Adulto Jovem
18.
Psychol Med ; 45(1): 11-27, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24569086

RESUMO

BACKGROUND: Individuals often avoid or delay seeking professional help for mental health problems. Stigma may be a key deterrent to help-seeking but this has not been reviewed systematically. Our systematic review addressed the overarching question: What is the impact of mental health-related stigma on help-seeking for mental health problems? Subquestions were: (a) What is the size and direction of any association between stigma and help-seeking? (b) To what extent is stigma identified as a barrier to help-seeking? (c) What processes underlie the relationship between stigma and help-seeking? (d) Are there population groups for which stigma disproportionately deters help-seeking? METHOD: Five electronic databases were searched from 1980 to 2011 and references of reviews checked. A meta-synthesis of quantitative and qualitative studies, comprising three parallel narrative syntheses and subgroup analyses, was conducted. RESULTS: The review identified 144 studies with 90,189 participants meeting inclusion criteria. The median association between stigma and help-seeking was d = - 0.27, with internalized and treatment stigma being most often associated with reduced help-seeking. Stigma was the fourth highest ranked barrier to help-seeking, with disclosure concerns the most commonly reported stigma barrier. A detailed conceptual model was derived that describes the processes contributing to, and counteracting, the deterrent effect of stigma on help-seeking. Ethnic minorities, youth, men and those in military and health professions were disproportionately deterred by stigma. CONCLUSIONS: Stigma has a small- to moderate-sized negative effect on help-seeking. Review findings can be used to help inform the design of interventions to increase help-seeking.


Assuntos
Transtornos Mentais/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Estigma Social , Atitude do Pessoal de Saúde , Feminino , Pessoal de Saúde/psicologia , Humanos , Masculino , Saúde Mental , Serviços de Saúde Mental , Militares/psicologia , Atenção Primária à Saúde , Pesquisa Qualitativa
19.
J Surg Oncol ; 111(8): 951-6, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26040651

RESUMO

BACKGROUND AND OBJECTIVES: Our study aimed to describe the clinical outcome of patients with superficial soft-tissue sarcomas (SSTS), define prognostic factors and provide evidence for a rational surveillance scheme. METHODS: Data for 622 consecutive, surgically treated SSTS patients were retrieved from the Scandinavian Sarcoma Group Register. We assessed the rates of local recurrence (LR) and metastasis (M), as well as overall survival (OS), local recurrence free-survival (LRFS) and metastasis-free survival (MFS) of the cohort. RESULTS: The incidence of LR and M was 9% and 12%, respectively. OS at 5 years was 79%, LRFS was 74% and MFS 76%. Factors that affected OS, LRFS, and MFS were tumor size and patient age. Additionally, tumor grade was an independent prognostic factor for LRFS. The majority of LR and M events were observed the first 2 years of follow-up. Clear surgical margins were correlated to lower risk for LR. Selected patients benefited from adjuvant radiotherapy. CONCLUSIONS: SSTS have a favourable prognosis, which is mainly determined by tumour-associated factors. Adequate surgical margins are important for local control, whereas radiotherapy has a secondary role. The data support current surveillance schemes, with a closer follow-up the first 2 years after surgery.


Assuntos
Sarcoma/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia/epidemiologia , Vigilância da População , Prognóstico , Sistema de Registros , Sarcoma/patologia , Sarcoma/cirurgia , Países Escandinavos e Nórdicos/epidemiologia , Análise de Sobrevida , Adulto Jovem
20.
J Surg Oncol ; 112(8): 853-60, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26482729

RESUMO

AIMS: The objectives of this study were to present changes in referral patterns, treatment and survival in patients with high-grade malignant bone sarcoma in Sweden and Norway based on data in the Scandinavian Sarcoma Group (SSG) Central Register. METHOD: Data on 1,437 patients with diagnosis 1986-2010 was analyzed. RESULTS: Osteosarcoma was the most frequentl diagnosis (45%), followed by Ewing sarcoma (21%) and chondrosarcoma (17%). Thirty-one percent of Swedish and 41% of Norwegian patients had tumors in the axial skeleton. Eighty-six percent of extremity tumors and 66% of axial tumors were referred to a sarcoma center prior to unplanned surgery or biopsy. During the past decade, limb salvage surgery has risen from under 50% to over 80%. Five-year overall survival in non-metastatic osteosarcoma was 70% for extremity tumors, and 35% for axial tumors. No improvement in osteosarcoma survival was observed during the last decade. Five-year survival in Ewing sarcoma improved from 50% to 69%. CONCLUSION: Referral patterns in bone sarcomas have improved. However, greater efforts should be dedicated to improving referral of patients with possible tumors in the axial skeleton to multidisciplinary teams (MDTs). Overall survival of patients with high-grade malignant bone sarcomas in Sweden and Norway is in line with other reports.


Assuntos
Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/terapia , Encaminhamento e Consulta/estatística & dados numéricos , Sistema de Registros , Sarcoma/diagnóstico , Sarcoma/terapia , Adolescente , Adulto , Idoso , Neoplasias Ósseas/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Noruega/epidemiologia , Sarcoma/mortalidade , Suécia/epidemiologia , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
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