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1.
Epidemiology ; 30(1): 93-102, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30063539

RESUMO

BACKGROUND: A few papers have considered reproducibility of a posteriori dietary patterns across populations, as well as pattern associations with head and neck cancer risk when multiple populations are available. METHODS: We used individual-level pooled data from seven case-control studies (3844 cases; 6824 controls) participating in the International Head and Neck Cancer Epidemiology consortium. We simultaneously derived shared and study-specific a posteriori patterns with a novel approach called multi-study factor analysis applied to 23 nutrients. We derived odds ratios (ORs) and 95% confidence intervals (CIs) for cancers of the oral cavity and pharynx combined, and larynx, from logistic regression models. RESULTS: We identified three shared patterns that were reproducible across studies (75% variance explained): the Antioxidant vitamins and fiber (OR = 0.57, 95% CI = 0.41, 0.78, highest versus lowest score quintile) and the Fats (OR = 0.80, 95% CI = 0.67, 0.95) patterns were inversely associated with oral and pharyngeal cancer risk. The Animal products and cereals (OR = 1.5, 95% CI = 1.1, 2.1) and the Fats (OR = 1.8, 95% CI = 1.4, 2.3) patterns were positively associated with laryngeal cancer risk, whereas a linear inverse trend in laryngeal cancer risk was evident for the Antioxidant vitamins and fiber pattern. We also identified four additional study-specific patterns, one for each of the four US studies examined. We named them all as Dairy products and breakfast cereals, and two were associated with oral and pharyngeal cancer risk. CONCLUSION: Multi-study factor analysis provides insight into pattern reproducibility and supports previous evidence on cross-country reproducibility of dietary patterns and on their association with head and neck cancer risk. See video abstract at, http://links.lww.com/EDE/B430.


Assuntos
Dieta , Neoplasias de Cabeça e Pescoço/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Intervalos de Confiança , Europa (Continente)/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Reprodutibilidade dos Testes , Estados Unidos/epidemiologia
2.
Br J Cancer ; 111(8): 1542-51, 2014 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-25137022

RESUMO

BACKGROUND: Magnetic resonance imaging (MRI) is recommended for women at high risk for breast cancer. We evaluated the cost-effectiveness of alternative screening strategies involving MRI. METHODS: Using a microsimulation model, we generated life histories under different risk profiles, and assessed the impact of screening on quality-adjusted life-years, and lifetime costs, both discounted at 3%. We compared 12 screening strategies combining annual or biennial MRI with mammography and clinical breast examination (CBE) in intervals of 0.5, 1, or 2 years vs without, and reported incremental cost-effectiveness ratios (ICERs). RESULTS: Based on an ICER threshold of $100,000/QALY, the most cost-effective strategy for women at 25% lifetime risk was to stagger MRI and mammography plus CBE every year from age 30 to 74, yielding ICER $58,400 (compared to biennial MRI alone). At 50% lifetime risk and with 70% reduction in MRI cost, the recommended strategy was to stagger MRI and mammography plus CBE every 6 months (ICER=$84,400). At 75% lifetime risk, the recommended strategy is biennial MRI combined with mammography plus CBE every 6 months (ICER=$62,800). CONCLUSIONS: The high costs of MRI and its lower specificity are limiting factors for annual screening schedule of MRI, except for women at sufficiently high risk.


Assuntos
Neoplasias da Mama/diagnóstico , Análise Custo-Benefício , Imageamento por Ressonância Magnética/estatística & dados numéricos , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/economia , Programas de Rastreamento/economia , Programas de Rastreamento/estatística & dados numéricos , Pessoa de Meia-Idade , Método de Monte Carlo , Fatores de Risco
3.
Epidemiol Psychiatr Sci ; 27(5): 492-499, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-28274298

RESUMO

AIMS: To evaluate treatment decision-making capacity (DMC) to consent to psychiatric treatment in involuntarily committed patients and to further investigate possible associations with clinical and socio-demographic characteristics of patients. METHODS: 131 involuntarily hospitalised patients were recruited in three university hospitals. Mental capacity to consent to treatment was measured with the MacArthur Competence Assessment Tool for Treatment (MacCAT-T); psychiatric symptoms severity (Brief Psychiatric Rating Scale, BPRS-E) and cognitive functioning (Mini Mental State Examination, MMSE) were also assessed. RESULTS: Mental capacity ratings for the 131 involuntarily hospitalised patients showed that patients affected by bipolar disorders (BD) scored generally better than those affected by schizophrenia spectrum disorders (SSD) in MacCAT-T appreciation (p < 0.05) and reasoning (p < 0.01). Positive symptoms were associated with poorer capacity to appreciate (r = -0.24; p < 0.01) and reason (r = -0.27; p < 0.01) about one's own treatment. Negative symptoms were associated with poorer understanding of treatment (r = -0.23; p < 0.01). Poorer cognitive functioning, as measured by MMSE, negatively affected MacCAT-T understanding in patients affected by SSD, but not in those affected by BD (SSD r = 0.37; p < 0.01; BD r = -0.01; p = 0.9). Poorer MacCAT-T reasoning was associated with more manic symptoms in the BD group of patients but not in the SSD group (BD r = -0.32; p < 0.05; SSD r = 0.03; p = 0.8). Twenty-two per cent (n = 29) of the 131 recruited patients showed high treatment DMC as defined by having scored higher than 75% of understanding, appreciating and reasoning MacCAT-T subscales maximum sores and 2 at expressing a choice. The remaining involuntarily hospitalised patients where considered to have low treatment DMC. Chi-squared disclosed that 32% of BD patients had high treatment DMC compared with 9% of SSD patients (p < 0.001). CONCLUSIONS: Treatment DMC can be routinely assessed in non-consensual psychiatric settings by the MacCAT-T, as is the case of other clinical variables. Such approach can lead to the identification of patients with high treatment DMC, thus drawing attention to possible dichotomy between legal and clinical status.


Assuntos
Internação Compulsória de Doente Mental , Tomada de Decisões , Consentimento Livre e Esclarecido/psicologia , Pacientes Internados/psicologia , Competência Mental , Participação do Paciente/psicologia , Adulto , Feminino , Hospitalização , Humanos , Itália , Masculino , Escalas de Graduação Psiquiátrica , Índice de Gravidade de Doença
4.
Nat Commun ; 8(1): 1893, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29196615

RESUMO

Multiple myeloma is a plasma cell malignancy characterized by recurrent IgH translocations and well described genomic heterogeneity. Although transcriptome profiles in multiple myeloma has been described, landscape of expressed fusion genes and their clinical impact remains unknown. To provide a comprehensive and detailed fusion gene cartography and suggest new mechanisms of tumorigenesis in multiple myeloma, we performed RNA sequencing in a cohort of 255 newly diagnosed and homogeneously treated multiple myeloma patients with long follow-up. Here, we report that patients have on average 5.5 expressed fusion genes. Kappa and lambda light chains and IgH genes are main partners in a third of all fusion genes. We also identify recurrent fusion genes that significantly impact both progression-free and overall survival and may act as drivers of the disease. Lastly, we find a correlation between the number of fusions, the age of patients and the clinical outcome, strongly suggesting that genomic instability drives prognosis of the disease.


Assuntos
Fusão Gênica , Mieloma Múltiplo/genética , Idoso , Feminino , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias kappa de Imunoglobulina/genética , Cadeias lambda de Imunoglobulina/genética , Masculino , Pessoa de Meia-Idade , Análise de Sequência de RNA , Translocação Genética
5.
J Endocrinol Invest ; 29(9): 805-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17114911

RESUMO

GH secretion by the pituitary is the result of the balance between the stimulatory effect of GHRH and the inhibitory effect of SS. Patients with mutations in GHRH receptor (GHRH-R) gene (GHRH-R) offer a unique model to study the mechanism of action of different GH secretion stimuli. In the past, we have demonstrated a small but significant GH response to a GH secretagogue (GHRP-2) in a homogenous cohort of patients with severe GH deficiency (GHD) due to a homozygous null mutation in GHRH-R (IVS1+1G-->A). Now, we sought to determine if we could detect a GH response to hypoglycemia (ITT: insulin tolerance test) or clonidine (CL) in these patients. Nine young GHD subjects underwent both ITT and CL tests, and 2 additional subjects underwent only CL test. There was a small but significant GH increase during ITT, but not during CL test. These results indicate that a minimal albeit significant GH response to ITT can occur despite complete lack of GHRH-R function.


Assuntos
Clonidina/farmacologia , Nanismo Hipofisário/sangue , Hormônio do Crescimento Humano/metabolismo , Hipoglicemia/metabolismo , Adolescente , Adulto , Glicemia/efeitos dos fármacos , Estatura , Criança , Pré-Escolar , Nanismo Hipofisário/genética , Feminino , Hormônio Liberador de Hormônio do Crescimento/genética , Hormônio do Crescimento Humano/sangue , Humanos , Hipoglicemia/induzido quimicamente , Insulina/efeitos adversos , Masculino , Síndrome , Fatores de Tempo
6.
J Natl Cancer Inst ; 90(23): 1824-9, 1998 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-9839523

RESUMO

BACKGROUND: The discovery of BRCA1 and BRCA2 has led to a reassessment of the association between family history of breast/ovarian cancer and breast cancer risk after controlling for carrier status for mutations in the BRCA1 and BRCA2 genes. We examined whether family history of breast cancer remains a predictive risk factor for this disease after carrier status for BRCA1 and/or BRCA2 mutations is taken into consideration. METHODS: The data are from 4730 case subjects with breast cancer and 4688 control subjects enrolled in the Cancer and Steroid Hormone Study. The probability of being a BRCA1 and/or BRCA2 gene carrier was calculated for each woman. Among predicted noncarriers, logistic regression was used to assess the relationship (odds ratios and 95% confidence intervals [CIs]) between case or control status and family history of breast or ovarian cancer. Estimates of age-specific breast cancer risk are presented by predicted carrier status. RESULTS: Among predicted noncarriers, case subjects were 2.06 times (95% CI = 1.69-2.50) and 1.24 times (95% CI = 1.17-1.32) more likely to report a first-degree or second-degree family history of breast cancer, respectively, than were control subjects. Case subjects were 1.99 times (95% CI = 1.63-2.44), 1.66 times (95% CI = 1.18-2.38), and 2.23 times (95% CI = 0.21-24.65) more likely to report an affected mother, sister, or both, respectively, than were control subjects. A family history of ovarian cancer was not statistically significantly associated with breast cancer risk. Noncarriers were predicted to have a lifetime risk of 9% of developing breast cancer compared with a 63% risk for carriers. CONCLUSIONS: Among women with a moderate family history of breast cancer, i.e., predicted noncarriers of BRCA1 and/or BRCA2 mutations, family history remains a factor in predicting breast cancer risk. In families with breast and ovarian cancers, the aggregation of these two cancers appears to be explained by BRCA1/BRCA2 mutation-carrier probability.


Assuntos
Neoplasias da Mama/genética , Genes BRCA1 , Genes Supressores de Tumor , Heterozigoto , Mutação , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Razão de Chances , Valor Preditivo dos Testes , Risco , Fatores de Risco
7.
J Natl Cancer Inst ; 89(3): 227-38, 1997 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-9017003

RESUMO

BACKGROUND: Heritable mutations of the breast cancer gene BRCA1 are rare, occurring in fewer than 1% of women in the general population, and therefore account for a small proportion of cases of breast and ovarian cancers. Nevertheless, the presence of such mutations is highly predictive of the development of these cancers. PURPOSE: We developed and applied a mathematic model for calculating the probability that a woman with a family history of breast and/or ovarian cancer carries a mutation of BRCA1. METHODS AND RESULTS: As a basis for the model, we use Mendelian genetics and apply Bayes' theorem to information on the family history of these diseases. Of importance are the exact relationships of all family members, including both affected and unaffected members, and ages at diagnosis of the affected members and current ages of the unaffected members. We used available estimates of BRCA1 mutation frequencies in the general population and age-specific incidence rates of breast and ovarian cancers in carriers and noncarriers of mutations to estimate the probability that a particular member of the family carries a mutation. This probability is based on cancer statuses of all first- and second-degree relatives. We first describe the model by considering single individuals: a woman diagnosed with breast and/or ovarian cancer and also a woman free of cancer. We next considered two artificial and two actual family histories and addressed the sensitivity of our calculations to various assumptions. Particular relationships of family members with and without cancer can have a substantial impact on the probability of carrying a susceptibility gene. Ages at diagnosis of affected family members and their types of cancer are also important. A woman with two primary cancers can have a probability of carrying a mutation in excess of 80%, even with no other information about family history. The number and relationships of unaffected members, along with their current ages or ages at death, are critical determinants of one's carrier probability. An affected woman with several cancers in her family can have a probability of carrying a mutation that ranges from close to 100% to less than 5%. CONCLUSION: Our model gives informative and specific probabilities that a particular woman carries a mutation. IMPLICATIONS: This model focuses on mutations in BRCA1 and assumes that all other breast cancer is sporadic. With the cloning of BRCA2, we now know that this assumption is incorrect. We have adjusted the model to include BRCA2, but the use of this version must await publication of penetrance data for BRCA2, including those for male breast cancer that are apparently associated with BRCA2 but not with BRCA1. The current model is, nevertheless, appropriate and useful. Of principal importance is its potential and that of improved versions for aiding women and their health care providers in assessing the need for genetic testing.


Assuntos
Neoplasias da Mama/genética , Família , Anamnese , Mutação , Neoplasias Ovarianas/genética , Adulto , Fatores Etários , Idoso , Teorema de Bayes , Feminino , Heterozigoto , Humanos , Pessoa de Meia-Idade , Modelos Teóricos , Razão de Chances , Linhagem , Prevalência , Risco
8.
Cancer Res ; 61(4): 1299-304, 2001 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11245424

RESUMO

We sequenced the complete 16.5-kb mitochondrial genome (mtDNA) in 15 pancreatic cancer cell lines and xenografts. Homoplasmic mtDNA somatic mutations and novel variants were identified in nearly all samples. Southern blot analysis and direct sequencing of mutation sites showed that the intracellular mass of mtDNA was greatly (6-8-fold) increased in pancreatic cancer cells in relation to corresponding normal cells; this property accounted for and greatly facilitated the identification of these mutations among the dense desmoplastic host reaction characteristic of primary pancreatic cancers. Structural characteristics and mathematical modeling of the evolution of mtDNA mutations suggested that many of the mutations identified might represent a random evolution of homoplasmic variants, rather than necessarily being a product of selective pressures. Complete sequencing of the nuclear MnSOD gene, which protects cells from the mitogenic and toxic effects of oxygen radicals, did not reveal any mutations. Nevertheless, the nearly ubiquitous prevalence and high copy number of mtDNA mutations suggest that they be considered of promising clinical utility in diagnostic applications.


Assuntos
Adenocarcinoma/genética , DNA Mitocondrial/genética , DNA de Neoplasias/genética , Frequência do Gene/genética , Mutação/fisiologia , Neoplasias Pancreáticas/genética , Animais , Southern Blotting , Análise Mutacional de DNA , Genoma Humano , Humanos , Modelos Genéticos , Transplante de Neoplasias , Reação em Cadeia da Polimerase , Superóxido Dismutase/genética , Transplante Heterólogo
9.
J Clin Oncol ; 17(5): 1465-73, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10334532

RESUMO

PURPOSE: Axillary lymph node dissection (ALND) has been a standard procedure in the management of breast cancer. In a patient with a clinically negative axilla, ALND is performed primarily for staging purposes, to guide adjuvant treatment. Recently, the routine use of ALND has been questioned because the results of the procedure may not change the choice of adjuvant systemic therapy and/or the survival benefit of a change in adjuvant therapy would be small. We constructed a decision model to quantify the benefits of ALND for patients eligible for breast-conserving therapy. METHODS: Patients were grouped by age, tumor size, and estrogen receptor (ER) status. The model uses the Oxford overviews and three combined Cancer and Leukemia Group B studies. We assumed that patients who did not undergo ALND received axillary radiation therapy and that the two procedures are equally effective. All chemotherapy combinations were assumed to be equally efficacious. RESULTS: The largest benefits from ALND are seen in ER-positive women with small primary tumors who might not be candidates for adjuvant chemotherapy if their lymph nodes test negative. Virtually no benefit results in ER-negative women, almost all of whom would receive adjuvant chemotherapy. When adjusted for quality of life (QOL), ALND may have an overall negative impact. In general, the benefits of ALND increase with the expected severity of adjuvant therapy on QOL CONCLUSION: Our model quantifies the benefits of ALND and assists decision making by patients and physicians. The results suggest that the routine use of ALND in breast cancer patients should be reassessed and may not be necessary in many patients.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Técnicas de Apoio para a Decisão , Excisão de Linfonodo , Anos de Vida Ajustados por Qualidade de Vida , Adulto , Axila , Neoplasias da Mama/química , Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Receptores de Estrogênio , Sensibilidade e Especificidade , Tamoxifeno/uso terapêutico
10.
Hum Pathol ; 32(4): 417-27, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11331959

RESUMO

Tissue microarray technology promises to enhance tissue-based molecular research by allowing improved conservation of tissue resources and experimental reagents, improved internal experimental control, and increased sample numbers per experiment. Organized, well-validated collection and analysis of the voluminous image data produced by tissue microarray technology is critical to maximize its value. Web-based technology for visual analysis and searchable storage of microarray image data could provide optimal flexibility for research groups in meeting this goal, but this approach has not been examined scientifically. Toward this goal, a prostate tissue microarray block containing 432 tissue cores (0.6 mm diameter) was constructed. Moderately compressed (200 kb).jpg images of each tissue spot were acquired and were saved using a naming convention developed by the SPORE Prostate Tissue Microarray Collaborative Group. Four hundred three tissue array spot images were uploaded into a database developed for this study and were converted to.fpx format to decrease Internet transmission times for high-resolution image data. In phase I of the image analysis portion of the study, testing and preliminary analysis of the Web technology was performed by 2 pathologists (M.A.R. and G.S.B.). In phase II, 2 pathologists (J.I.E. and T.M.W.) with no previous exposure to this technology and no knowledge of the structure of the study were presented a set of 130 sequential tissue spot images via the Web on their office computers. In phase III, the same pathologists were presented a set of 193 images, including all 130 from phase II and 63 others, with image presentation order randomized. With each zoomable tissue spot image, each pathologist was presented with a nested set of questions regarding overall interpretability of the image, presence or absence of cancer, and predominant and second most frequent Gleason grade. In phases II and III of the study, 319 of 323 (99%) image presentations using this Web technology were rated interpretable. Comparing the 2 pathologists' readings in phases II and III, Gleason grade determinations by each pathologist were identical in 179 of 221 (81%) determinations and were within 1 point of each other in 221 of 221 (100%) determinations, a performance rate similar to if not better than that previously reported for direct microscopic Gleason grading. Interobserver comparison of Gleason score determinations and intraobserver comparisons for Gleason grade and score also showed a pattern of uniformity similar to those reported in direct microscope-based Gleason grading studies. Interobserver (7.5%) and intraobserver (5% and 3%) variability in determining whether diagnosable cancer was present point out the existence of a "threshold effect" that has rarely been studied but may provide a basis for identification of features that are most amenable to improved diagnostic standardization. In summary, storage and analysis of tissue microarray spot images using Web-based technology is feasible and practical, and the quality of images obtained using the techniques described here appears adequate for most tissue-based pathology research applications. HUM PATHOL 32:417-427.


Assuntos
Bases de Dados Factuais , Processamento de Imagem Assistida por Computador , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Humanos , Masculino , Neoplasias da Próstata
11.
J Clin Epidemiol ; 52(3): 259-71, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10210244

RESUMO

A recent national panel on cost-effectiveness in health and medicine has recommended that cost-effectiveness analysis (CEA) of randomized controlled trials (RCTs) should reflect the effect of treatments on long-term outcomes. Because the follow-up period of RCTs tends to be relatively short, long-term implications of treatments must be assessed using other sources. We used a comprehensive simulation model of the natural history of stroke to estimate long-term outcomes after a hypothetical RCT of an acute stroke treatment. The RCT generates estimates of short-term quality-adjusted survival and cost and also the pattern of disability at the conclusion of follow-up. The simulation model incorporates the effect of disability on long-term outcomes, thus supporting a comprehensive CEA. Treatments that produce relatively modest improvements in the pattern of outcomes after ischemic stroke are likely to be cost-effective. This conclusion was robust to modifying the assumptions underlying the analysis. More effective treatments in the acute phase immediately following stroke would generate significant public health benefits, even if these treatments have a high price and result in relatively small reductions in disability. Simulation-based modeling can provide the critical link between a treatment's short-term effects and its long-term implications and can thus support comprehensive CEA.


Assuntos
Isquemia Encefálica/economia , Isquemia Encefálica/epidemiologia , Técnicas de Apoio para a Decisão , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Doença Aguda , Isquemia Encefálica/terapia , Simulação por Computador , Análise Custo-Benefício/estatística & dados numéricos , Avaliação da Deficiência , Humanos , Modelos Econômicos , Método de Monte Carlo , Avaliação de Resultados em Cuidados de Saúde , Anos de Vida Ajustados por Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto/economia , Fatores de Risco , Sensibilidade e Especificidade , Análise de Sobrevida , Resultado do Tratamento , Estados Unidos/epidemiologia
12.
Med Decis Making ; 18(2 Suppl): S39-56, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9566466

RESUMO

Predictions of cost over well-defined time horizons are frequently required in the analysis of clinical trials and social experiments, for decision models investigating the cost-effectiveness of interventions, and for macro-level estimates of the resource impact of disease. With rare exceptions, cost predictions used in such applications continue to take the form of deterministic point estimates. However, the growing availability of large administrative and clinical data sets offers new opportunities for a more general approach to disease cost forecasting: the estimation of multivariable cost functions that yield predictions at the individual level, conditional on intervention(s), patient characteristics, and other factors. This raises the fundamental question of how to choose the "best" cost model for a given application. The central purpose of this paper is to demonstrate how to evaluate competing models on the basis of predictive validity. This concept is operationalized according to three alternative criteria: 1) root mean square error (RMSE), for evaluating predicted mean cost; 2) mean absolute error (MAE), for evaluating predicted median cost; and 3) a logarithmic scoring rule (log score), an information-theoretic index for evaluating the entire predictive distribution of cost. To illustrate these concepts, the authors conducted a split-sample analysis of data from a national sample of Medicare-covered patients hospitalized for ischemic stroke in 1991 and followed to the end of 1993. Using test and training samples of about 500,000 observations each, they investigated five models: single-equation linear models, with and without log transform of cost; two-part (mixture) models, with and without log transform, to directly address the problem of zero-cost observations; and a Cox proportional-hazards model stratified by time interval. For deriving the predictive distribution of cost, the log transformed two-part and proportional-hazards models are superior. For deriving the predicted mean or median cost, these two models and the commonly used log-transformed linear model all perform about the same. The untransformed models are dominated in every instance. The approaches to model selection illustrated here can be applied across a wide range of settings.


Assuntos
Transtornos Cerebrovasculares/economia , Efeitos Psicossociais da Doença , Modelos Econométricos , Custos e Análise de Custo/métodos , Hospitalização/economia , Hospitalização/estatística & dados numéricos , Humanos , Modelos Estatísticos , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais
13.
Med Decis Making ; 17(4): 390-401, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9343797

RESUMO

A framework for quantifying uncertainty about costs, effectiveness measures, and marginal cost-effectiveness ratios in complex decision models is presented. This type of application requires special techniques because of the multiple sources of information and the model-based combination of data. The authors discuss two alternative approaches, one based on Bayesian inference and the other on resampling. While computationally intensive, these are flexible in handling complex distributional assumptions and a variety of outcome measures of interest. These concepts are illustrated using a simplified model. Then the extension to a complex decision model using the stroke-prevention policy model is described.


Assuntos
Técnicas de Apoio para a Decisão , Custos de Cuidados de Saúde/estatística & dados numéricos , Teorema de Bayes , Transtornos Cerebrovasculares/economia , Transtornos Cerebrovasculares/prevenção & controle , Simulação por Computador , Análise Custo-Benefício , Humanos , Modelos Estatísticos , Anos de Vida Ajustados por Qualidade de Vida
14.
Breast Dis ; 10(1-2): 115-25, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15687554

RESUMO

Tests for the presence of mutations of genes BRCA1 and BRCA2 are increasingly available. Genetic testing creates dilemmas for women and men who regard themselves to be at high risk for breast cancer. Who will benefit from genetic testing? What is the benefit? Does testing improve quality of life? An important consideration in addressing these questions is the woman's chance of carrying a mutation at BRCA1 or BRCA2. Also important are the effectiveness and cost of the testing procedure, the availability of prophylactic interventions, the effectiveness and negative aspects of interventions, the impact of testing on other family members, and the impact of testing on the woman's ability to obtain insurance coverage. In this article we review the development of a statistical model for predicting whether a woman is a carrier of a BRCA1 or a BRCA2 mutation. We also show how this calculation can be used to assess the benefit of testing, and we quantify the size of the benefit in terms of its improvement on quality-adjusted life years (QALYs).

15.
Stat Methods Med Res ; 11(6): 513-37, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12516987

RESUMO

Prediction models used in support of clinical and health policy decision making often need to consider the course of a disease over an extended period of time, and draw evidence from a broad knowledge base, including epidemiologic cohort and case control studies, randomized clinical trials, expert opinions, and more. This paper is a brief introduction to these complex decision models, their relation to Bayesian decision theory, and the tools typically used to describe the uncertainties involved. Concepts are illustrated throughout via a simplified tutorial.


Assuntos
Teorema de Bayes , Técnicas de Apoio para a Decisão , Pesquisa sobre Serviços de Saúde/métodos , Modelos Estatísticos , Análise Custo-Benefício , Interpretação Estatística de Dados , Medicina Baseada em Evidências , Humanos , Probabilidade , Sensibilidade e Especificidade , Acidente Vascular Cerebral/prevenção & controle
19.
Zh Nevrol Psikhiatr Im S S Korsakova ; 109(7 Suppl 2): 16-22, 2009.
Artigo em Russo | MEDLINE | ID: mdl-19894308

RESUMO

Unrelated patients with definite multiple sclerosis (MS) and healthy controls of Russian descent were genotyped at 16 polymorphic loci of the DRB1, TNF, LTa, TGFb1, CCR5 and CTLA4 genes and TNFa and TNFb microsatellites. The association of allelic variants with MS (p<0,01) was studied using the case-control method with the PSampler algorithm recently developed by our group. The previously described DRB1*15(2) allele, the TNFa9 allele and the biallelic combination (CCR5d32,DRB1*04) were reidentified as MS-associated in Russians. We also identified previously unknown MS-associated tri-allelic combinations: (-509 TGFb1*C, DRB1*18(3),CTLA4*G) and (-238TNF*B1, -308TNF*A2,CTLA4*G). The biological properties of the MS-associated genes support the notion that autoimmune inflammatory processes play an important role in MS, whereas an existence of mainly non-overlapping subgroups of patients bearing different predisposing genetic factors is consistent with the MS genetic heterogeneity.


Assuntos
Autoimunidade/genética , DNA/genética , Predisposição Genética para Doença , Antígenos HLA-DR/genética , Esclerose Múltipla/genética , Polimorfismo Genético/imunologia , Fator de Necrose Tumoral alfa/genética , Adulto , Alelos , Feminino , Variação Genética , Genótipo , Cadeias HLA-DRB1 , Humanos , Masculino , Esclerose Múltipla/imunologia , Reação em Cadeia da Polimerase
20.
Oncogene ; 27(57): 7180-91, 2008 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-18794802

RESUMO

Cancer cells differentiate along specific lineages that largely determine their clinical and biologic behavior. Distinct cancer phenotypes from different cells and organs likely result from unique gene expression repertoires established in the embryo and maintained after malignant transformation. We used comprehensive gene expression analysis to examine this concept in the prostate, an organ with a tractable developmental program and a high propensity for cancer. We focused on gene expression in the murine prostate rudiment at three time points during the first 48 h of exposure to androgen, which initiates proliferation and invasion of prostate epithelial buds into surrounding urogenital sinus mesenchyme. Here, we show that androgen exposure regulates genes previously implicated in prostate carcinogenesis comprising pathways for the phosphatase and tensin homolog (PTEN), fibroblast growth factor (FGF)/mitogen-activated protein kinase (MAPK), and Wnt signaling along with cellular programs regulating such 'hallmarks' of cancer as angiogenesis, apoptosis, migration and proliferation. We found statistically significant evidence for novel androgen-induced gene regulation events that establish and/or maintain prostate cell fate. These include modulation of gene expression through microRNAs, expression of specific transcription factors, and regulation of their predicted targets. By querying public gene expression databases from other tissues, we found that rather than generally characterizing androgen exposure or epithelial budding, the early prostate development program more closely resembles the program for human prostate cancer. Most importantly, early androgen-regulated genes and functional themes associated with prostate development were highly enriched in contrasts between increasingly lethal forms of prostate cancer, confirming a 'reactivation' of embryonic pathways for proliferation and invasion in prostate cancer progression. Among the genes with the most significant links to the development and cancer, we highlight coordinate induction of the transcription factor Sox9 and suppression of the proapoptotic phospholipid-binding protein Annexin A1 that link early prostate development to early prostate carcinogenesis. These results credential early prostate development as a reliable and valid model system for the investigation of genes and pathways that drive prostate cancer.


Assuntos
Androgênios/metabolismo , Desenvolvimento Embrionário/genética , Perfilação da Expressão Gênica , Próstata/embriologia , Neoplasias da Próstata/genética , Transdução de Sinais/fisiologia , Animais , Diferenciação Celular/fisiologia , Proliferação de Células , Transformação Celular Neoplásica/genética , Células Epiteliais/citologia , Imunofluorescência , Expressão Gênica , Imuno-Histoquímica , Hibridização In Situ , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias da Próstata/metabolismo , Análise Serial de Tecidos
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