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1.
Breast Cancer Res Treat ; 205(3): 497-506, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38459395

RESUMO

PURPOSE: Although infertility (i.e., failure to conceive after ≥ 12 months of trying) is strongly correlated with established breast cancer risk factors (e.g., nulliparity, number of pregnancies, and age at first pregnancy), its association with breast cancer incidence is not fully understood. Previous studies were primarily small clinic-based or registry studies with short follow-up and predominantly focused on premenopausal breast cancer. The objective of this study was to assess the relationship between infertility and postmenopausal breast cancer risk among participants in the Women's Health Initiative (analytic sample = 131,784; > 25 years of follow-up). METHODS: At study entry, participants were asked about their pregnancy history, infertility history, and diagnosed reasons for infertility. Incident breast cancers were self-reported with adjudication by trained physicians reviewing medical records. Cox proportional hazards models were used to estimate risk of incident postmenopausal breast cancer for women with infertility (overall and specific infertility diagnoses) compared to parous women with no history of infertility. We examined mediation of these associations by parity, age at first term pregnancy, postmenopausal hormone therapy use at baseline, age at menopause, breastfeeding, and oophorectomy. RESULTS: We observed a modest association between infertility (n = 23,406) and risk of postmenopausal breast cancer (HR = 1.07; 95% CI 1.02-1.13). The association was largely mediated by age at first term pregnancy (natural indirect effect: 46.4% mediated, CI 12.2-84.3%). CONCLUSION: These findings suggest that infertility may be modestly associated with future risk of postmenopausal breast cancer due to age at first pregnancy and highlight the importance of incorporating reproductive history across the life course into breast cancer analyses.


Assuntos
Neoplasias da Mama , Pós-Menopausa , Humanos , Feminino , Neoplasias da Mama/epidemiologia , Pessoa de Meia-Idade , Fatores de Risco , Incidência , Idoso , Saúde da Mulher , Infertilidade Feminina/epidemiologia , Infertilidade Feminina/etiologia , Modelos de Riscos Proporcionais , Gravidez , Estados Unidos/epidemiologia , Infertilidade/epidemiologia
2.
Gastroenterology ; 163(5): 1252-1266.e2, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35850192

RESUMO

BACKGROUND & AIMS: Pancreatic ductal adenocarcinoma (PDAC) incidence is rising worldwide, and most patients present with an unresectable disease at initial diagnosis. Measurement of carbohydrate antigen 19-9 (CA19-9) levels lacks adequate sensitivity and specificity for early detection; hence, there is an unmet need to develop alternate molecular diagnostic biomarkers for PDAC. Emerging evidence suggests that tumor-derived exosomal cargo, particularly micro RNAs (miRNAs), offer an attractive platform for the development of cancer-specific biomarkers. Herein, genomewide profiling in blood specimens was performed to develop an exosome-based transcriptomic signature for noninvasive and early detection of PDAC. METHODS: Small RNA sequencing was undertaken in a cohort of 44 patients with an early-stage PDAC and 57 nondisease controls. Using machine-learning algorithms, a panel of cell-free (cf) and exosomal (exo) miRNAs were prioritized that discriminated patients with PDAC from control subjects. Subsequently, the performance of the biomarkers was trained and validated in independent cohorts (n = 191) using quantitative reverse transcription polymerase chain reaction (qRT-PCR) assays. RESULTS: The sequencing analysis initially identified a panel of 30 overexpressed miRNAs in PDAC. Subsequently using qRT-PCR assays, the panel was reduced to 13 markers (5 cf- and 8 exo-miRNAs), which successfully identified patients with all stages of PDAC (area under the curve [AUC] = 0.98 training cohort; AUC = 0.93 validation cohort); but more importantly, was equally robust for the identification of early-stage PDAC (stages I and II; AUC = 0.93). Furthermore, this transcriptomic signature successfully identified CA19-9 negative cases (<37 U/mL; AUC = 0.96), when analyzed in combination with CA19-9 levels, significantly improved the overall diagnostic accuracy (AUC = 0.99 vs AUC = 0.86 for CA19-9 alone). CONCLUSIONS: In this study, an exosome-based liquid biopsy signature for the noninvasive and robust detection of patients with PDAC was developed.


Assuntos
Adenocarcinoma , Carcinoma Ductal Pancreático , Exossomos , MicroRNAs , Neoplasias Pancreáticas , Humanos , Antígeno CA-19-9 , Exossomos/genética , Exossomos/patologia , Transcriptoma , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Biomarcadores Tumorais/genética , Estudos de Coortes , MicroRNAs/genética , Carboidratos , Neoplasias Pancreáticas
3.
Breast Cancer Res Treat ; 192(1): 113-122, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35039952

RESUMO

PURPOSE: To examine benefit of sulindac for relief of musculoskeletal symptoms (MSS) in patients stable on aromatase inhibitors (AIs). METHODS: Sulindac was evaluated at 150 mg twice daily for effects on MSS at 3, 6, 9, and 12 months in 50 postmenopausal women stable on AI therapy for a median of 12.5 months for hormone receptor-positive breast cancer. A separate, non-randomized group of 50 similar patients was observed for change in MSS over 12 months. MSS severity was assessed using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index and Brief Pain Inventory Short Form (BPI-SF). The Functional Assessment of Cancer Therapy-General form (FACT-G) measured quality of life (QOL). Change in MSS and QOL across time was assessed in each group using linear mixed effects models. RESULTS: Stiffness, not pain, was the main complaint at baseline. At 12 months, sulindac patients reported decreases (improvements) in mean (95% CI) Total WOMAC score [- 5.85 (- 9.73, - 1.96)] and WOMAC pain [- 5.40 (- 10.64, - 0 .18)], Stiffness [- 9.53 (- 14.98, - 4.08)] and Physical Function [- 5.61 (- 9.62, - 1.60)] subscales, but not BPI-SF worst pain. Among sulindac patients with higher baseline MSS severity, 35% experienced ≥ 50% improvement in Total WOMAC and Total FACT-G scores [6.18 (2.08, 10.27); P = 0.003]. For the observation group, MSS and QOL did not improve over 12 months, even among those with higher baseline MSS severity. CONCLUSIONS: Sulindac may relieve MSS in AI patients, especially physical function and stiffness. Randomized controlled trials should further evaluate NSAIDs on AI-MSS and AI adherence. TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION: NCT01761877, December, 2012.


Assuntos
Inibidores da Aromatase , Neoplasias da Mama , Sulindaco , Inibidores da Aromatase/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Feminino , Humanos , Dor , Qualidade de Vida , Sulindaco/uso terapêutico , Resultado do Tratamento
4.
Breast Cancer Res Treat ; 190(1): 69-78, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34383179

RESUMO

PURPOSE: Obesity is a known risk factor for post-menopausal breast cancer and may increase risk for triple negative breast cancer in premenopausal women. Intervention strategies are clearly needed to reduce obesity-associated breast cancer risk. METHODS: We conducted a Phase II double-blind, randomized, placebo-controlled trial of metformin in overweight/obese premenopausal women with components of metabolic syndrome to assess the potential of metformin for primary breast cancer prevention. Eligible participants were randomized to receive metformin (850 mg BID, n = 76) or placebo (n = 75) for 12 months. Outcomes included breast density, assessed by fat/water MRI with change in percent breast density as the primary endpoint, anthropometric measures, and intervention feasibility. RESULTS: Seventy-six percent in the metformin arm and 83% in the placebo arm (p = 0.182) completed the 12-month intervention. Adherence to study agent was high with more than 80% of participants taking ≥ 80% assigned pills. The most common adverse events reported in the metformin arm were gastrointestinal in nature and subsided over time. Compared to placebo, metformin intervention led to a significant reduction in waist circumference (p < 0.001) and waist-to-hip ratio (p = 0.019). Compared to placebo, metformin did not change percent breast density and dense breast volume but led to a numerical but not significant decrease in non-dense breast volume (p = 0.070). CONCLUSION: We conclude that metformin intervention resulted in favorable changes in anthropometric measures of adiposity and a borderline decrease in non-dense breast volume in women with metabolic dysregulation. More research is needed to understand the impact of metformin on breast cancer risk reduction. TRIAL REGISTRATION: ClinicalTrials.gov NCT02028221. Registered January 7, 2014, https://clinicaltrials.gov/ct2/show/NCT02028221.


Assuntos
Neoplasias da Mama , Síndrome Metabólica , Metformina , Adiposidade , Densidade da Mama , Neoplasias da Mama/complicações , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/epidemiologia , Estudos de Viabilidade , Feminino , Humanos , Mamografia , Síndrome Metabólica/complicações , Síndrome Metabólica/tratamento farmacológico , Síndrome Metabólica/epidemiologia , Metformina/efeitos adversos , Obesidade/complicações , Obesidade/tratamento farmacológico
5.
J Immunol ; 203(10): 2577-2587, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31591149

RESUMO

The MHC class I Ag presentation pathway in melanoma cells has a well-established role in immune-mediated destruction of tumors. However, the clinical significance of the MHC class II Ag presentation pathway in melanoma cells is less clear. In Ag-presenting cells, IFN-γ-inducible lysosomal thiol reductase (GILT) is critical for MHC class II-restricted presentation of multiple melanoma Ags. Although not expressed in benign melanocytes of nevi, GILT and MHC class II expression is induced in malignant melanocytes in a portion of melanoma specimens. Analysis of The Cancer Genome Atlas cutaneous melanoma data set showed that high GILT mRNA expression was associated with improved overall survival. Expression of IFN-γ, TNF-α, and IL-1ß was positively associated with GILT expression in melanoma specimens. These cytokines were capable of inducing GILT expression in human melanoma cells in vitro. GILT protein expression in melanocytes was induced in halo nevi, which are nevi undergoing immune-mediated regression, and is consistent with the association of GILT expression with improved survival in melanoma. To explore potential mechanisms of GILT's association with patient outcome, we investigated pathways related to GILT function and expression. In contrast to healthy skin specimens, in which the MHC class II pathway was nearly uniformly expressed and intact, there was substantial variation in the MHC class II pathway in the The Cancer Genome Atlas melanoma specimens. Both an active and intact MHC class II pathway were associated with improved overall survival in melanoma. These studies support a role for GILT and the MHC class II Ag presentation pathway in melanoma outcome.


Assuntos
Apresentação de Antígeno/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Melanoma/imunologia , Melanoma/mortalidade , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/metabolismo , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/mortalidade , Adolescente , Linhagem Celular Tumoral , Feminino , Células HEK293 , Humanos , Interferon gama/metabolismo , Interferon gama/farmacologia , Masculino , Melanoma/patologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Recombinantes/farmacologia , Neoplasias Cutâneas/patologia , Taxa de Sobrevida , Adulto Jovem , Melanoma Maligno Cutâneo
6.
BMC Public Health ; 21(1): 346, 2021 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-33579240

RESUMO

BACKGROUND: Exposure to gestational diabetes mellitus (GDM) is associated with increased risk for type 2 diabetes (T2DM) in mothers, and poor cardiovascular health among offspring. Identifying effective methods to mitigate T2DM risk has the potential to improve health outcomes for mothers with a history of GDM and their children. The goal of the EPIC El Rio Families Study is to implement and evaluate the effects of a 13-week behavioral lifestyle intervention on T2DM risk factors in at-risk mothers and their 8- to 12-year-old children. We describe herein the rationale for our specific approach, the adaption of the DPP-based curriculum for delivery to patients of a Federally Qualified Health Center (FQHC), and the study design and methodology. METHODS: The effects of the intervention on reduction in excess body weight (primary outcome), hemoglobin A1c, blood pressure, and changes in lifestyle behaviors associated with weight trajectory and T2DM risk in mother-child dyads will be evaluated during a 13-week, group randomized trial wherein 60 mothers and their children will be recruited to the intervention or wait-listed control conditions at one of two FQHC locations. Intervention participants (n = 30) will begin the group program immediately, whereas the wait-listed controls (n = 30) will receive a booklet describing self-guided strategies for behavior change. Associated program delivery costs, acceptability of the program to participants and FQHC staff, and potential for long-term sustainability will also be evaluated. DISCUSSION: Successful completion in our aims will produce a scalable program with high potential for replication and dissemination, and estimated intervention effects to inform T2DM prevention efforts on families who use the FQHC system. The results from this study will be critical in developing a T2DM prevention model that can be implemented and scaled across FQHCs serving populations disproportionately burdened by T2DM. TRIAL REGISTRATION: ClinicalTrials.gov NCT03781102 ; Date of registration: 19 December 2018.


Assuntos
Diabetes Mellitus Tipo 2 , Diabetes Gestacional , Criança , Atenção à Saúde , Diabetes Mellitus Tipo 2/prevenção & controle , Feminino , Hemoglobinas Glicadas/análise , Humanos , Estilo de Vida , Mães , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
Breast Cancer Res Treat ; 184(3): 771-778, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32860167

RESUMO

PURPOSE: Chemotherapy-induced peripheral neuropathy (CIPN) is caused by drug-induced damage to the axons which is not detected easily due to lack of reliable, clinically applicable modalities. Diffuse tensor imaging (DTI) allows for quantitative measurements of fractional anisotropy (FA) and apparent diffusion coefficient (ADC), which have been shown to detect nerve injury by Magnetic Resonance Imaging (MRI). METHODS: We sought to evaluate if DTI could be used for detection of CIPN in patients with breast cancer treated with a taxane. Patients with h/o exposure to neurotoxic chemotherapy, diabetes, or peripheral neuropathy were excluded. Patients completed pre- and post-chemotherapy MRI of bilateral legs and FACT&GOG-Ntx. Genotyping of single-nucleotide variations (SNVs) was performed to detect known associations with CIPN. RESULTS: We had 14 evaluable patients in this prospective trial. Mean FA values post-chemotherapy were significantly lower than baseline at mid-calf (p < 0.0001) and ankle (p = 0.03). We did not find any significant change in mean ADC values. In patients without symptomatic neuropathy, mean FA values decreased more than symptomatic patients at mid-calf (p < 0.001). Of the 41 genotyped SNVs, only rs8110536 was found to be significantly associated with development of CIPN. CONCLUSIONS: Our results show that FA values are indicative of CIPN and differential changes in FA values in symptomatic versus asymptomatic patients highlights its potential to be further studied as a predictive biomarker for CIPN. This is the first study to highlight a non-invasive, imaging based, objective biomarker which, if validated, can be translated into clinic easily.


Assuntos
Antineoplásicos , Neoplasias da Mama , Doenças do Sistema Nervoso Periférico , Antineoplásicos/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Imagem de Tensor de Difusão , Feminino , Humanos , Extremidade Inferior , Imageamento por Ressonância Magnética , Doenças do Sistema Nervoso Periférico/diagnóstico , Doenças do Sistema Nervoso Periférico/diagnóstico por imagem , Estudos Prospectivos
8.
BMC Med Res Methodol ; 20(1): 50, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-32122312

RESUMO

BACKGROUND: Longitudinal randomized controlled trials (RCTs) often aim to test and measure the effect of treatment between arms at a single time point. A two-sample χ2 test is a common statistical approach when outcome data are binary. However, only complete outcomes are used in the analysis. Missing responses are common in longitudinal RCTs and by only analyzing complete data, power may be reduced and estimates could be biased. Generalized linear mixed models (GLMM) with a random intercept can be used to test and estimate the treatment effect, which may increase power and reduce bias. METHODS: We simulated longitudinal binary RCT data to compare the performance of a complete case χ2 test to a GLMM in terms of power, type I error, relative bias, and coverage under different missing data mechanisms (missing completely at random and missing at random). We considered how the baseline probability of the event, within subject correlation, and dropout rates under various missing mechanisms impacted each performance measure. RESULTS: When outcome data were missing completely at random, both χ2 and GLMM produced unbiased estimates; however, the GLMM returned an absolute power gain up to from 12.0% as compared to the χ2 test. When outcome data were missing at random, the GLMM yielded an absolute power gain up to 42.7% and estimates were unbiased or less biased compared to the χ2 test. CONCLUSIONS: Investigators wishing to test for a treatment effect between treatment arms in longitudinal RCTs with binary outcome data in the presence of missing data should use a GLMM to gain power and produce minimally unbiased estimates instead of a complete case χ2 test.


Assuntos
Algoritmos , Simulação por Computador , Modelos Lineares , Avaliação de Resultados em Cuidados de Saúde/métodos , Interpretação Estatística de Dados , Humanos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos
9.
Clin Infect Dis ; 68(9): 1547-1555, 2019 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-30239609

RESUMO

BACKGROUND: The majority of tuberculosis transmission occurs in community settings. Our primary aim in this study was to assess the association between exposure to community venues and multidrug-resistant (MDR) tuberculosis. Our secondary aim was to describe the social networks of MDR tuberculosis cases and controls. METHODS: We recruited laboratory-confirmed MDR tuberculosis cases and community controls that were matched on age and sex. Whole-genome sequencing was used to identify genetically clustered cases. Venue tracing interviews (nonblinded) were conducted to enumerate community venues frequented by participants. Logistic regression was used to assess the association between MDR tuberculosis and person-time spent in community venues. A location-based social network was constructed, with respondents connected if they reported frequenting the same venue, and an exponential random graph model (ERGM) was fitted to model the network. RESULTS: We enrolled 59 cases and 65 controls. Participants reported 729 unique venues. The mean number of venues reported was similar in both groups (P = .92). Person-time in healthcare venues (adjusted odds ratio [aOR] = 1.67, P = .01), schools (aOR = 1.53, P < .01), and transportation venues (aOR = 1.25, P = .03) was associated with MDR tuberculosis. Healthcare venues, markets, cinemas, and transportation venues were commonly shared among clustered cases. The ERGM indicated significant community segregation between cases and controls. Case networks were more densely connected. CONCLUSIONS: Exposure to healthcare venues, schools, and transportation venues was associated with MDR tuberculosis. Intervention across the segregated network of case venues may be necessary to effectively stem transmission.


Assuntos
Busca de Comunicante/estatística & dados numéricos , Farmacorresistência Bacteriana Múltipla , Mycobacterium tuberculosis/genética , Rede Social , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/transmissão , Adulto , Antituberculosos/uso terapêutico , Estudos de Casos e Controles , Comércio , Feminino , Instalações de Saúde , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Filmes Cinematográficos , Família Multigênica , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/crescimento & desenvolvimento , Peru/epidemiologia , Instituições Acadêmicas , Meios de Transporte , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
10.
Int J Obes (Lond) ; 42(6): 1185-1194, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29892038

RESUMO

BACKGROUND/OBJECTIVE: Childhood obesity has been separately associated with cardiometabolic risk factors (CMRs) and increased risk of fracture. However, both augmented and compromised bone mass have been reported among overweight/obese children. Metabolic dysfunction, often co-existing with obesity, may explain the discrepancy in previous studies. The aim of this study was to examine whether the relationship between adiposity and dual-energy X-ray absorptiometry (DXA) derived bone mass differed in young girls with and without CMR(s). SUBJECTS/METHODS: Whole-body bone and body composition measures by DXA and measures of CMR (fasting glucose, high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), systolic and diastolic blood pressure, waist circumference (WC)) were obtained from 307, 9- to 12-year-old girls. Girls with 1 or ≥ 2 CMR(s) were considered to be at risk (vs. no CMR). Multiple linear regression was used to test the relationship of total fat mass with total body bone mineral content (BMC) after controlling for height, lean mass, CMR risk, and other potential confounders. RESULTS: There was a significant interaction between CMR risk and total body fat mass. When girls were stratified by CMR group, all groups had a significant positive relationship between fat mass and BMC (p < 0.05), however, girls with ≥ 2 CMRs had a lower BMC for a given level of body fat. Total body fat was not significantly related to bone mineral density (p > 0.05). CONCLUSION: Fat mass has a positive relationship with BMC even after controlling for lean mass. However, the positive relationship of fat mass with BMC may be attenuated if multiple CMRs are present.


Assuntos
Adiposidade/fisiologia , Densidade Óssea/fisiologia , Doenças Cardiovasculares/etiologia , Síndrome Metabólica/etiologia , Obesidade Infantil/complicações , Absorciometria de Fóton , Pressão Sanguínea , Composição Corporal , Índice de Massa Corporal , Doenças Cardiovasculares/fisiopatologia , Criança , HDL-Colesterol , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Síndrome Metabólica/fisiopatologia , Obesidade Infantil/metabolismo , Obesidade Infantil/fisiopatologia , Estudos Prospectivos , Fatores de Risco , Triglicerídeos , Circunferência da Cintura
11.
J Magn Reson Imaging ; 48(4): 971-981, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29630755

RESUMO

BACKGROUND: Increased breast density is a significant independent risk factor for breast cancer, and recent studies show that this risk is modifiable. Hence, breast density measures sensitive to small changes are desired. PURPOSE: Utilizing fat-water decomposition MRI, we propose an automated, reproducible breast density measurement, which is nonionizing and directly comparable to mammographic density (MD). STUDY TYPE: Retrospective study. POPULATION: The study included two sample sets of breast cancer patients enrolled in a clinical trial, for concordance analysis with MD (40 patients) and reproducibility analysis (10 patients). FIELD STRENGTH/SEQUENCE: The majority of MRI scans (59 scans) were performed with a 1.5T GE Signa scanner using radial IDEAL-GRASE sequence, while the remaining (seven scans) were performed with a 3T Siemens Skyra using 3D Cartesian 6-echo GRE sequence with a similar fat-water separation technique. ASSESSMENT: After automated breast segmentation, breast density was calculated using FraGW, a new measure developed to reliably reflect the amount of fibroglandular tissue and total water content in the entire breast. Based on its concordance with MD, FraGW was calibrated to MR-based breast density (MRD) to be comparable to MD. A previous breast density measurement, Fra80-the ratio of breast voxels with <80% fat fraction-was also calculated for comparison with FraGW. STATISTICAL TESTS: Pearson correlation was performed between MD (reference standard) and FraGW (and Fra80). Test-retest reproducibility of MRD was evaluated using the difference between test-retest measures (Δ1-2 ) and intraclass correlation coefficient (ICC). RESULTS: Both FraGW and Fra80 were strongly correlated with MD (Pearson ρ: 0.96 vs. 0.90, both P < 0.0001). MRD converted from FraGW showed higher test-retest reproducibility (Δ1-2 variation: 1.1% ± 1.2%; ICC: 0.99) compared to MD itself (literature intrareader ICC ≤0.96) and Fra80. DATA CONCLUSION: The proposed MRD is directly comparable with MD and highly reproducible, which enables the early detection of small breast density changes and treatment response. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;48:971-981.


Assuntos
Densidade da Mama , Neoplasias da Mama/diagnóstico por imagem , Mama/diagnóstico por imagem , Imageamento por Ressonância Magnética , Radiação Ionizante , Tecido Adiposo/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Mamografia , Reconhecimento Automatizado de Padrão , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Risco , Tamoxifeno/uso terapêutico , Água
12.
Biometrics ; 74(3): 1045-1054, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29534304

RESUMO

Continuous-time Markov models are commonly used to analyze longitudinal transitions between multiple disease states in panel data, where participants' disease states are only observed at multiple time points, and the exact state paths between observations are unknown. However, when covariate effects are incorporated and allowed to vary for different transitions, the number of potential parameters to estimate can become large even when the number of covariates is moderate, and traditional maximum likelihood estimation and subset model selection procedures can easily become unstable due to overfitting. We propose a novel regularized continuous-time Markov model with the elastic net penalty, which is capable of simultaneous variable selection and estimation for large number of parameters. We derive an efficient coordinate descent algorithm to solve the penalized optimization problem, which is fully automatic and data driven. We further consider an extension where one of the states is death, and time of death is exactly known but the state path leading to death is unknown. The proposed method is extensively evaluated in a simulation study, and demonstrated in an application to real-world data on airflow limitation state transitions.


Assuntos
Algoritmos , Progressão da Doença , Cadeias de Markov , Simulação por Computador , Humanos , Modelos Estatísticos , Fatores de Tempo
13.
J Trop Pediatr ; 64(2): 146-150, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28673047

RESUMO

Anthropometric measurements, including height and length, are routinely needed for health research worldwide. Measurement boards are the current gold standard for obtaining the height and length of children. In community-based research, however, the size and weight of the measurement boards make them difficult and cumbersome to carry in the field. In addition, children and infants may express an unwillingness to be placed onto the measurement board. Electronic measuring tools commonly used in industry and contracting work are precise and portable. This study piloted a protocol to use an adapted laser measurement tool, the anthropometric measurement assist (AMA), to obtain height and recumbent length in children in Western Kenya. Intra- and inter-observer variability were determined and compared with measurement board measurements. Results of this initial pilot indicated that the AMA may be a viable alternative to measurement boards. The AMA can measure height/length accurately and reliably, is portable and is equivalent in price to measuring boards, making it a viable option for fieldwork in low-resourced countries.


Assuntos
Antropometria/instrumentação , Lasers/estatística & dados numéricos , Saúde Pública/métodos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Quênia , Masculino , Variações Dependentes do Observador , Projetos Piloto , Reprodutibilidade dos Testes
14.
Breast Cancer Res Treat ; 165(1): 97-107, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28560655

RESUMO

PURPOSE: Diindolylmethane (DIM), a bioactive metabolite of indole-3-carbinol found in cruciferous vegetables, has proposed cancer chemoprevention activity in the breast. There is limited evidence of clinically relevant activity of DIM or long-term safety data of its regular use. A randomized, double-blind, placebo-controlled trial was conducted to determine the activity and safety of combined use of BioResponse DIM® (BR-DIM) with tamoxifen. METHODS: Women prescribed tamoxifen (n = 130) were randomly assigned oral BR-DIM at 150 mg twice daily or placebo, for 12 months. The primary study endpoint was change in urinary 2/16α-hydroxyestrone (2/16α-OHE1) ratio. Changes in 4-hydroxyestrone (4-OHE1), serum estrogens, sex hormone-binding globulin (SHBG), breast density, and tamoxifen metabolites were assessed. RESULTS: Ninety-eight women (51 placebo, 47 DIM) completed intervention; compliance with treatment was >91%. BR-DIM increased the 2/16α-OHE1 ratio (+3.2 [0.8, 8.4]) compared to placebo (-0.7 [-1.7, 0.8], P < 0.001). Serum SHBG increased with BR-DIM compared to placebo (+25 ± 22 and +1.1 ± 19 nmol/L, respectively). No change in breast density measured by mammography or by MRI was observed. Plasma tamoxifen metabolites (endoxifen, 4-OH tamoxifen, and N-desmethyl-tamoxifen) were reduced in women receiving BR-DIM versus placebo (P < 0.001). Minimal adverse events were reported and did not differ by treatment arm. CONCLUSION: In patients taking tamoxifen for breast cancer, daily BR-DIM promoted favorable changes in estrogen metabolism and circulating levels of SHBG. Further research is warranted to determine whether BR-DIM associated decreases in tamoxifen metabolites, including effects on endoxifen levels, attenuates the clinical benefit of tamoxifen. TRIAL REGISTRATION: ClinicalTrials.gov NCT01391689.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais , Neoplasias da Mama/tratamento farmacológico , Indóis/administração & dosagem , Tamoxifeno/administração & dosagem , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/sangue , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/urina , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Neoplasias da Mama/urina , Método Duplo-Cego , Feminino , Humanos , Hidroxiestronas/sangue , Hidroxiestronas/urina , Indóis/efeitos adversos , Mamografia , Pessoa de Meia-Idade , Globulina de Ligação a Hormônio Sexual/metabolismo , Tamoxifeno/efeitos adversos , Tamoxifeno/sangue , Fatores de Tempo , Resultado do Tratamento
15.
J Nutr ; 147(3): 421-429, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28122932

RESUMO

Background: Several lifestyle factors targeted by the American Cancer Society (ACS) Nutrition and Physical Activity Cancer Prevention Guidelines are also associated with circulating concentrations of vitamin D metabolites. This suggests that greater adherence to the ACS guidelines may be related to better vitamin D status.Objective: We examined the relation between adherence to the ACS guidelines and circulating concentrations of 2 vitamin D metabolites, 25-hydroxycholecalciferol [25(OH)D] and 1α,25-dihydroxyvitamin D [1,25(OH)2D].Methods: We conducted cross-sectional analyses of pooled participants from the Wheat Bran Fiber (n = 503) and Ursodeoxycholic Acid (n = 854) trials. A cumulative adherence score was constructed with the use of baseline data on body size, diet, physical activity, and alcohol consumption. Continuous vitamin D metabolite concentrations and clinically relevant categories were evaluated with the use of multiple linear and logistic regression models, respectively.Results: The most adherent participants were more likely to be older, white, and nonsmokers than were the least adherent. A statistically significant association was observed between guideline adherence and concentrations of circulating 25(OH)D (means ± SEs-high adherence: 32.0 ± 0.8 ng/mL; low adherence: 26.4 ± 0.7 ng/mL; P-trend < 0.001). For 1,25(OH)2D concentrations, high adherence was again significantly related to greater metabolite concentrations, with mean ± SE concentrations of 36.3 ± 1.3 pg/mL and 31.9 ± 1.0 pg/mL for high- and low-adherers, respectively (P-trend = 0.008). Furthermore, the odds of attaining a sufficient 25(OH)D status were 4.37 times higher for those most adherent than for those least adherent (95% CI: 2.47, 7.71 times).Conclusion: These findings demonstrate that greater adherence to the ACS guidelines is associated with higher circulating concentrations of both of 25(OH)D and 1,25(OH)2D.


Assuntos
Neoplasias Colorretais/prevenção & controle , Fibras na Dieta , Cooperação do Paciente , Ácido Ursodesoxicólico/farmacologia , Vitamina D/análogos & derivados , Adenoma/prevenção & controle , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vitamina D/sangue
16.
Blood ; 124(8): 1259-65, 2014 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-25016003

RESUMO

Lymphoma cells are subject to higher levels of oxidative stress compared with their normal counterparts and may be vulnerable to manipulations of the cellular redox balance. We therefore designed a phase 2 study of imexon (Amplimexon/NSC-714597), a prooxidant molecule, in patients with relapsed/refractory B-cell non-Hodgkin lymphoma (NHL). Imexon was administered at 1000 mg/m(2) IV daily for 5 days in 21-day cycles. Gene expression analysis performed on pretreatment tumor specimens included 13 transcripts used to generate a redox signature score, previously demonstrated to correlate with lymphoma prognosis. Twenty-two patients were enrolled having follicular (n = 9), diffuse large B-cell (DLBCL) (n = 5), mantle cell (n = 3), transformed follicular (n = 2), small lymphocytic (n = 2), and Burkitt (n = 1) lymphoma. The most common grade 3/4 adverse events were anemia (14%) and neutropenia (9%). The overall response rate was 30%, including responses in follicular lymphoma (4 of 9) and DLBCL (2 of 5). Gene expression analyses revealed CD68 and the redox-related genes, GPX1 and SOD2, as well as a higher redox score to correlate with clinical responses. Therefore, pretreatment markers of oxidative stress may identify patients likely to respond to this therapeutic approach. This trial was registered at www.clinicaltrials.gov as #NCT01314014.


Assuntos
Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hexanonas/administração & dosagem , Oxidantes/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/biossíntese , Intervalo Livre de Doença , Feminino , Glutationa Peroxidase/biossíntese , Hexanonas/efeitos adversos , Humanos , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/metabolismo , Linfoma de Células B/mortalidade , Linfoma de Células B/patologia , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/biossíntese , Oxidantes/efeitos adversos , Recidiva , Superóxido Dismutase/biossíntese , Taxa de Sobrevida , Glutationa Peroxidase GPX1
17.
BMC Cancer ; 16: 500, 2016 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-27430256

RESUMO

BACKGROUND: Two-thirds of U.S. adult women are overweight or obese. High body mass index (BMI) and adult weight gain are risk factors for a number of chronic diseases, including postmenopausal breast cancer. The higher postmenopausal breast cancer risk in women with elevated BMI is likely to be attributable to related metabolic disturbances including altered circulating sex steroid hormones and adipokines, elevated pro-inflammatory cytokines, and insulin resistance. Metformin is a widely used antidiabetic drug that has demonstrated favorable effects on metabolic disturbances and as such may lead to lower breast cancer risk in obese women. Further, the anti-proliferative effects of metformin suggest it may decrease breast density, an accepted biomarker of breast cancer risk. METHODS/DESIGN: This is a Phase II randomized, double-blind, placebo-controlled trial of metformin in overweight/obese premenopausal women who have elements of metabolic syndrome. Eligible participants will be randomized to receive metformin 850 mg BID (n = 75) or placebo (n = 75) for 12 months. The primary endpoint is change in breast density, based on magnetic resonance imaging (MRI) acquired fat-water features. Secondary outcomes include changes in serum insulin levels, serum insulin-like growth factor (IGF)-1 to insulin-like growth factor binding protein (IGFBP)-3 ratio, serum IGF-2 levels, serum testosterone levels, serum leptin to adiponectin ratio, body weight, and waist circumference. Exploratory outcomes include changes in metabolomic profiles in plasma and nipple aspirate fluid. Changes in tissue architecture as well as cellular and molecular targets in breast tissue collected in a subgroup of participants will also be explored. DISCUSSION: The study will evaluate whether metformin can result in favorable changes in breast density, select proteins and hormones, products of body metabolism, and body weight and composition. The study should help determine the potential breast cancer preventive activity of metformin in a growing population at risk for multiple diseases. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02028221 . Registered on January 2, 2014. Grant #: 1R01CA172444-01A1 awarded on Sept 11, 2013.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Mama/efeitos dos fármacos , Metformina/uso terapêutico , Obesidade/complicações , Adiponectina/sangue , Adulto , Peso Corporal/efeitos dos fármacos , Mama/diagnóstico por imagem , Mama/patologia , Neoplasias da Mama/sangue , Neoplasias da Mama/complicações , Método Duplo-Cego , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/sangue , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Leptina/sangue , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Obesidade/sangue , Avaliação de Resultados em Cuidados de Saúde , Fatores de Risco , Testosterona/sangue , Circunferência da Cintura/efeitos dos fármacos
18.
BMC Med Res Methodol ; 16(1): 154, 2016 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-27842498

RESUMO

BACKGROUND: The study of circulating biomarkers and their association with disease outcomes has become progressively complex due to advances in the measurement of these biomarkers through multiplex technologies. The Least Absolute Shrinkage and Selection Operator (LASSO) is a data analysis method that may be utilized for biomarker selection in these high dimensional data. However, it is unclear which LASSO-type method is preferable when considering data scenarios that may be present in serum biomarker research, such as high correlation between biomarkers, weak associations with the outcome, and sparse number of true signals. The goal of this study was to compare the LASSO to five LASSO-type methods given these scenarios. METHODS: A simulation study was performed to compare the LASSO, Adaptive LASSO, Elastic Net, Iterated LASSO, Bootstrap-Enhanced LASSO, and Weighted Fusion for the binary logistic regression model. The simulation study was designed to reflect the data structure of the population-based Tucson Epidemiological Study of Airway Obstructive Disease (TESAOD), specifically the sample size (N = 1000 for total population, 500 for sub-analyses), correlation of biomarkers (0.20, 0.50, 0.80), prevalence of overweight (40%) and obese (12%) outcomes, and the association of outcomes with standardized serum biomarker concentrations (log-odds ratio = 0.05-1.75). Each LASSO-type method was then applied to the TESAOD data of 306 overweight, 66 obese, and 463 normal-weight subjects with a panel of 86 serum biomarkers. RESULTS: Based on the simulation study, no method had an overall superior performance. The Weighted Fusion correctly identified more true signals, but incorrectly included more noise variables. The LASSO and Elastic Net correctly identified many true signals and excluded more noise variables. In the application study, biomarkers of overweight and obesity selected by all methods were Adiponectin, Apolipoprotein H, Calcitonin, CD14, Complement 3, C-reactive protein, Ferritin, Growth Hormone, Immunoglobulin M, Interleukin-18, Leptin, Monocyte Chemotactic Protein-1, Myoglobin, Sex Hormone Binding Globulin, Surfactant Protein D, and YKL-40. CONCLUSIONS: For the data scenarios examined, choice of optimal LASSO-type method was data structure dependent and should be guided by the research objective. The LASSO-type methods identified biomarkers that have known associations with obesity and obesity related conditions.


Assuntos
Obesidade/diagnóstico , Algoritmos , Área Sob a Curva , Biomarcadores/sangue , Humanos , Modelos Logísticos , Modelos Biológicos , Obesidade/sangue , Sobrepeso/sangue , Sobrepeso/diagnóstico , Curva ROC
19.
Am J Ther ; 23(1): e86-91, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-23982695

RESUMO

This study was a 14-day, outpatient, open-label randomized crossover trial of lyophilized black raspberries (BRBs) in older overweight or obese males to determine whether BRB consumption affects postprandial inflammation associated with consumption of a high-fat high-calorie (HFHC) meal. Ten study participants consumed 45 g/d of lyophilized BRBs for 4 days, followed by a HFHC breakfast plus BRBs on day 6 or consumed the HFHC breakfast on day 6 without previous consumption of BRBs and then crossed over to the other treatment after a 2-day washout period. Blood samples were obtained before and 1, 2, 4, 8, and 12 hours after consumption of the HFHC breakfast. The primary study outcomes were changes in area under the concentration-time curve (AUC) for interleukin-6 (IL-6), C-reactive protein (CRP), and tumor necrosis factor-alpha (TNF-α). The secondary outcomes were safety and tolerability of lyophilized BRB powder. The chronology and values of measured serum concentrations for IL-6, TNF-α, and CRP were consistent with those described previously by other investigators. The AUC of serum IL-6 was lowered significantly (P = 0.03, n = 10) with BRB consumption (34.3 ± 7.6 pg·mL⁻¹·h⁻¹ compared with 42.4 ± 17.9 pg·mL⁻¹·h⁻¹ for consumption of the HFHC meal alone). However, no significant differences (change in AUC) were calculated for serum CRP and TNF-α. The findings of this pilot study suggest that consumption of lyophilized BRBs may attenuate postprandial inflammation in overweight or obese males consuming a HFHC meal. Further investigation of BRBs is warranted to better elucidate their inflammomodulatory potential.


Assuntos
Inflamação/tratamento farmacológico , Sobrepeso/complicações , Fitoterapia , Rubus , Idoso , Proteína C-Reativa/análise , Estudos Cross-Over , Dieta Hiperlipídica , Liofilização , Humanos , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Período Pós-Prandial
20.
Int Arch Occup Environ Health ; 89(2): 251-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26126735

RESUMO

PURPOSE: This study sought to develop a comprehensive measure of fitness that is predictive of injury risk and can be used in the fire service to assess individual-level health and fit-for-duty status. METHODS: A retrospective occupational cohort of 799 career fire service employees was observed over the years 2005-2009. An equally weighted score for comprehensive fitness was calculated based on cardiovascular fitness, muscular strength, endurance, flexibility, and body composition. Repeated measures survival analyses were used to estimate the risk of any injury, sprain or strain, and exercise-related injuries in relation to comprehensive fitness. RESULTS: A well-distributed comprehensive fitness score was developed to distinguish three tiers of overall fitness status. Intraclass correlations identified flexibility, total grip strength, percent body fat, and resting heart rate as the most reliable fitness metrics, while push-ups, sit-ups, and aerobic capacity demonstrated poor reliability. In general, individuals with a lower comprehensive fitness status had an increased injury risk of injury as compared to the most fit individuals. The risk of any injury was 1.82 (95% CI 1.06-3.11) times as likely for the least fit individuals, as compared to individuals in the top fire fitness category, increasing to 2.90 (95% CI 1.48-5.66) when restricted to sprains and strains. CONCLUSIONS: This 5-year analysis of clinical occupational health assessments enabled the development of a relevant metric for relating comprehensive fitness with the risk of injury. Results were consistent with previous studies focused on cardiorespiratory fitness, but also less susceptible to inter-individual variability of discrete measurements.


Assuntos
Bombeiros , Traumatismos Ocupacionais/epidemiologia , Aptidão Física/fisiologia , Avaliação da Capacidade de Trabalho , Adiposidade , Adulto , Teste de Esforço , Feminino , Força da Mão , Frequência Cardíaca , Humanos , Masculino , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Sudoeste dos Estados Unidos/epidemiologia , Entorses e Distensões/epidemiologia
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