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1.
J Invasive Cardiol ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38814904

RESUMO

A 59-year-old diabetic man with a history of numerous coronary angiographies (CAs) and peripheral artery disease underwent CA due to a non-ST elevation myocardial infarction. Femoral, radial, and ulnar arteries were unpalpable.

2.
J Geriatr Oncol ; 15(5): 101774, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38676975

RESUMO

INTRODUCTION: High-intensity end-of-life (EoL) care can be burdensome for patients, caregivers, and health systems and does not confer any meaningful clinical benefit. Yet, there are significant knowledge gaps regarding the predictors of high-intensity EoL care. In this study, we identify risk factors associated with high-intensity EoL care among older adults with the four most common malignancies, including breast, prostate, lung, and colorectal cancer. MATERIALS AND METHODS: Using SEER-Medicare data, we conducted a retrospective analysis of Medicare beneficiaries aged 65 and older who died of breast, prostate, lung, or colorectal cancer between 2011 and 2015. We used multivariable logistic regression to identify clinical, demographic, socioeconomic, and geographic predictors of high-intensity EoL care, which we defined as death in an acute care hospital, receipt of any oral or parenteral chemotherapy within 14 days of death, one or more admissions to the intensive care unit within 30 days of death, two or more emergency department visits within 30 days of death, or two or more inpatient admissions within 30 days of death. RESULTS: Among 59,355 decedents, factors associated with increased likelihood of receiving high-intensity EoL care were increased comorbidity burden (odds ratio [OR]:1.29; 95% confidence interval [CI]:1.28-1.30), female sex (OR:1.05; 95% CI:1.01-1.09), Black race (OR:1.14; 95% CI:1.07-1.23), Other race/ethnicity (OR:1.20; 95% CI:1.10-1.30), stage III disease (OR:1.11; 95% CI:1.05-1.18), living in a county with >1,000,000 people (OR:1.23; 95% CI:1.16-1.31), living in a census tract with 10%-<20% poverty (OR:1.09; 95% CI:1.03-1.16) or 20%-100% poverty (OR:1.12; 95% CI:1.04-1.19), and having state-subsidized Medicare premiums (OR:1.18; 95% CI:1.12-1.24). The risk of high-intensity EoL care was lower among patients who were older (OR:0.98; 95% CI:0.98-0.99), lived in the Midwest (OR:0.69; 95% CI:0.65-0.75), South (OR:0.70; 95% CI:0.65-0.74), or West (OR:0.81; 95% CI:0.77-0.86), lived in mostly rural areas (OR:0.92; 95% CI:0.86-1.00), and had poor performance status (OR:0.26; 95% CI:0.25-0.28). Results were largely consistent across cancer types. DISCUSSION: The risk factors identified in our study can inform the development of new interventions for patients with cancer who are likely to receive high-intensity EoL care. Health systems should consider incorporating these risk factors into decision-support tools to assist clinicians in identifying which patients should be referred to hospice and palliative care.


Assuntos
Medicare , Neoplasias , Programa de SEER , Assistência Terminal , Humanos , Masculino , Assistência Terminal/estatística & dados numéricos , Feminino , Idoso , Estudos Retrospectivos , Estados Unidos/epidemiologia , Medicare/estatística & dados numéricos , Idoso de 80 Anos ou mais , Neoplasias/terapia , Neoplasias/epidemiologia , Neoplasias/mortalidade , Neoplasias Colorretais/terapia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/epidemiologia , Fatores de Risco , Modelos Logísticos , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/epidemiologia , Neoplasias da Próstata/terapia , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/epidemiologia , Neoplasias da Mama/terapia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/epidemiologia , Hospitalização/estatística & dados numéricos
3.
Global Spine J ; : 21925682241248110, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38613478

RESUMO

STUDY DESIGN: Observational Study. OBJECTIVES: This study aimed to investigate the most searched types of questions and online resources implicated in the operative and nonoperative management of scoliosis. METHODS: Six terms related to operative and nonoperative scoliosis treatment were searched on Google's People Also Ask section on October 12, 2023. The Rothwell classification was used to sort questions into fact, policy, or value categories, and associated websites were classified by type. Fischer's exact tests compared question type and websites encountered between operative and nonoperative questions. Statistical significance was set at the .05 level. RESULTS: The most common questions concerning operative and nonoperative management were fact (53.4%) and value (35.5%) questions, respectively. The most common subcategory pertaining to operative and nonoperative questions were specific activities/restrictions (21.7%) and evaluation of treatment (33.3%), respectively. Questions on indications/management (13.2% vs 31.2%, P < .001) and evaluation of treatment (10.1% vs 33.3%, P < .001) were associated with nonoperative scoliosis management. Medical practice websites were the most common website to which questions concerning operative (31.9%) and nonoperative (51.4%) management were directed to. Operative questions were more likely to be directed to academic websites (21.7% vs 10.0%, P = .037) and less likely to be directed to medical practice websites (31.9% vs 51.4%, P = .007) than nonoperative questions. CONCLUSIONS: During scoliosis consultations, spine surgeons should emphasize the postoperative recovery process and efficacy of conservative treatment modalities for the operative and nonoperative management of scoliosis, respectively. Future research should assess the impact of website encounters on patients' decision-making.

4.
Stat Methods Med Res ; 33(4): 647-668, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38445348

RESUMO

The performance of individual biomarkers in discriminating between two groups, typically the healthy and the diseased, may be limited. Thus, there is interest in developing statistical methodologies for biomarker combinations with the aim of improving upon the individual discriminatory performance. There is extensive literature referring to biomarker combinations under the two-class setting. However, the corresponding literature under a three-class setting is limited. In our study, we provide parametric and nonparametric methods that allow investigators to optimally combine biomarkers that seek to discriminate between three classes by minimizing the Euclidean distance from the receiver operating characteristic surface to the perfection corner. Using this Euclidean distance as the objective function allows for estimation of the optimal combination coefficients along with the optimal cutoff values for the combined score. An advantage of the proposed methods is that they can accommodate biomarker data from all three groups simultaneously, as opposed to a pairwise analysis such as the one implied by the three-class Youden index. We illustrate that the derived true classification rates exhibit narrower confidence intervals than those derived from the Youden-based approach under a parametric, flexible parametric, and nonparametric kernel-based framework. We evaluate our approaches through extensive simulations and apply them to real data sets that refer to liver cancer patients.


Assuntos
Curva ROC , Humanos , Simulação por Computador , Biomarcadores
5.
Global Spine J ; : 21925682241241241, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38513636

RESUMO

STUDY DESIGN: Comparative study. OBJECTIVES: This study aims to compare Google and GPT-4 in terms of (1) question types, (2) response readability, (3) source quality, and (4) numerical response accuracy for the top 10 most frequently asked questions (FAQs) about anterior cervical discectomy and fusion (ACDF). METHODS: "Anterior cervical discectomy and fusion" was searched on Google and GPT-4 on December 18, 2023. Top 10 FAQs were classified according to the Rothwell system. Source quality was evaluated using JAMA benchmark criteria and readability was assessed using Flesch Reading Ease and Flesch-Kincaid grade level. Differences in JAMA scores, Flesch-Kincaid grade level, Flesch Reading Ease, and word count between platforms were analyzed using Student's t-tests. Statistical significance was set at the .05 level. RESULTS: Frequently asked questions from Google were varied, while GPT-4 focused on technical details and indications/management. GPT-4 showed a higher Flesch-Kincaid grade level (12.96 vs 9.28, P = .003), lower Flesch Reading Ease score (37.07 vs 54.85, P = .005), and higher JAMA scores for source quality (3.333 vs 1.800, P = .016). Numerically, 6 out of 10 responses varied between platforms, with GPT-4 providing broader recovery timelines for ACDF. CONCLUSIONS: This study demonstrates GPT-4's ability to elevate patient education by providing high-quality, diverse information tailored to those with advanced literacy levels. As AI technology evolves, refining these tools for accuracy and user-friendliness remains crucial, catering to patients' varying literacy levels and information needs in spine surgery.

6.
Int J Mol Sci ; 25(4)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38397007

RESUMO

Early-stage lung adenocarcinoma (LUAD) patients remain at substantial risk for recurrence and disease-related death, highlighting the unmet need of biomarkers for the assessment and identification of those in an early stage who would likely benefit from adjuvant chemotherapy. To identify circulating miRNAs useful for predicting recurrence in early-stage LUAD, we performed miRNA microarray analysis with pools of pretreatment plasma samples from patients with stage I LUAD who developed recurrence or remained recurrence-free during the follow-up period. Subsequent validation in 85 patients with stage I LUAD resulted in the development of a circulating miRNA panel comprising miR-23a-3p, miR-320c, and miR-125b-5p and yielding an area under the curve (AUC) of 0.776 in predicting recurrence. Furthermore, the three-miRNA panel yielded an AUC of 0.804, with a sensitivity of 45.8% at 95% specificity in the independent test set of 57 stage I and II LUAD patients. The miRNA panel score was a significant and independent factor for predicting disease-free survival (p < 0.001, hazard ratio [HR] = 1.64, 95% confidence interval [CI] = 1.51-4.22) and overall survival (p = 0.001, HR = 1.51, 95% CI = 1.17-1.94). This circulating miRNA panel is a useful noninvasive tool to stratify early-stage LUAD patients and determine an appropriate treatment plan with maximal efficacy.


Assuntos
Adenocarcinoma de Pulmão , MicroRNA Circulante , Neoplasias Pulmonares , MicroRNAs , Humanos , MicroRNA Circulante/genética , Biomarcadores Tumorais/genética , Adenocarcinoma de Pulmão/genética , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética
7.
Stat Med ; 43(3): 606-623, 2024 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-38038216

RESUMO

Tuberculosis (TB) studies often involve four different states under consideration, namely, "healthy," "latent infection," "pulmonary active disease," and "extra-pulmonary active disease." While highly accurate clinical diagnosis tests do exist, they are expensive and generally not accessible in regions where they are most needed; thus, there is an interest in assessing the accuracy of new and easily obtainable biomarkers. For some such biomarkers, the typical stochastic ordering assumption might not be justified for all disease classes under study, and usual ROC methodologies that involve ROC surfaces and hypersurfaces are inadequate. Different types of orderings may be appropriate depending on the setting, and these may involve a number of ambiguously ordered groups that stochastically exhibit larger (or lower) marker scores than the remaining groups. Recently, there has been scientific interest on ROC methods that can accommodate these so-called "tree" or "umbrella" orderings. However, there is limited work discussing the estimation of cutoffs in such settings. In this article, we discuss the estimation and inference around optimized cutoffs when accounting for such configurations. We explore different cutoff alternatives and provide parametric, flexible parametric, and non-parametric kernel-based approaches for estimation and inference. We evaluate our approaches using simulations and illustrate them through a real data set that involves TB patients.


Assuntos
Biomarcadores , Intervalos de Confiança , Humanos
8.
Sci Rep ; 13(1): 18341, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37884576

RESUMO

High grade serous ovarian carcinoma (HGSOC) accounts for ~ 70% of ovarian cancer cases. Non-invasive, highly specific blood-based tests for pre-symptomatic screening in women are crucial to reducing the mortality associated with this disease. Since most HGSOCs typically arise from the fallopian tubes (FT), our biomarker search focused on proteins found on the surface of extracellular vesicles (EVs) released by both FT and HGSOC tissue explants and representative cell lines. Using mass spectrometry, 985 EV proteins (exo-proteins) were identified that comprised the FT/HGSOC EV core proteome. Transmembrane exo-proteins were prioritized because these could serve as antigens for capture and/or detection. With a nano-engineered microfluidic platform, six newly discovered exo-proteins (ACSL4, IGSF8, ITGA2, ITGA5, ITGB3, MYOF) plus a known HGSOC associated protein, FOLR1 exhibited classification performance ranging from 85 to 98% in a case-control study using plasma samples representative of early (including stage IA/B) and late stage (stage III) HGSOCs. Furthermore, by a linear combination of IGSF8 and ITGA5 based on logistic regression analysis, we achieved a sensitivity of 80% with 99.8% specificity and a positive predictive value of 13.8%. Importantly, these exo-proteins also can accurately discriminate between ovarian and 12 types of cancers commonly diagnosed in women. Our studies demonstrate that these lineage-associated exo-biomarkers can detect ovarian cancer with high specificity and sensitivity early and potentially while localized to the FT when patient outcomes are more favorable.


Assuntos
Vesículas Extracelulares , Neoplasias Ovarianas , Humanos , Feminino , Estudos de Casos e Controles , Detecção Precoce de Câncer , Neoplasias Ovarianas/patologia , Vesículas Extracelulares/metabolismo , Biomarcadores Tumorais/metabolismo , Receptor 1 de Folato
9.
Front Mol Biosci ; 10: 1138594, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37122563

RESUMO

Ewing Sarcoma (EWS) is the second most common osseous malignancy in children and young adults after osteosarcoma, while it is the fifth common osseous malignancy within adult age population. The clinical presentation of EWS is quite often non-specific, with the most common symptoms at presentation consisting of pain, swelling or general discomfort. The dearth of clinically relevant diagnostic or predictive biomarkers continues to remain a pressing clinical challenge. Identification of tumor specific biomarkers can lend towards an early diagnosis, expedited initiation of therapy, monitoring of therapeutic response, and early detection of recurrence of disease. We carried-out a complex analysis of cell lines and cell line derived small extracellular vesicles (sEVs) using label-free-based Quantitative Proteomic Profiling with an intent to determine shared and distinct features of these tumor cells and their respective sEVs. We analyzed EWS cells with different EWS-ETS fusions (EWS-FLI1 type I, II, and III and EWS-ERG) and their corresponding sEVs. Non-EWS controls included osteosarcoma, rhabdomyosarcoma, and benign cells, i.e., osteoid osteoma and mesenchymal stem cells. Proteomic profiling identified new shared markers between cells and their corresponding cell-derived sEVs and markers which were exclusively enriched in EWS-derived sEVs. These exo-biomarkers identified were validated by in silico approaches of publicly available protein databases and by capillary electrophoresis based western analysis (Wes). Here, we identified a protein biomarker named UGT3A2 and found its expression highly specific to EWS cells and their sEVs compared to control samples. Clinical validation of UGT3A2 expression in patient tumor tissues and plasma derived sEV samples demonstrated its specificity to EWS, indicating its potential as a EWS biomarker.

10.
Res Methods Med Health Sci ; 4(1): 34-48, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37009524

RESUMO

Studies that investigate the performance of prognostic and predictive biomarkers are commonplace in medicine. Evaluating the performance of biomarkers is challenging in traumatic brain injury (TBI) and other conditions when both the time factor (i.e. time from injury to biomarker measurement) and different levels or doses of treatments are in play. Such factors need to be accounted for when assessing the biomarker's performance in relation to a clinical outcome. The Hyperbaric Oxygen in Brain Injury Treatment (HOBIT) trial, a phase II randomized control clinical trial seeks to determine the dose of hyperbaric oxygen therapy (HBOT) for treating severe TBI that has the highest likelihood of demonstrating efficacy in a phase III trial. Hyperbaric Oxygen in Brain Injury Treatment will study up to 200 participants with severe TBI. This paper discusses the statistical approaches to assess the prognostic and predictive performance of the biomarkers studied in this trial, where prognosis refers to the association between a biomarker and the clinical outcome while the predictiveness refers to the ability of the biomarker to identify patient subgroups that benefit from therapy. Analyses based on initial biomarker levels accounting for different levels of HBOT and other baseline clinical characteristics, and analyses of longitudinal changes in biomarker levels are discussed from a statistical point of view. Methods for combining biomarkers that are of complementary nature are also considered and the relevant algorithms are illustrated in detail along with an extensive simulation study that assesses the performance of the statistical methods. Even though the discussed approaches are motivated by the HOBIT trial, their applications are broader. They can be applied in studies assessing the predictiveness and prognostic ability of biomarkers in relation to a well-defined therapeutic intervention and clinical outcome.

11.
Bioengineering (Basel) ; 10(4)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37106610

RESUMO

The human fallopian tube epithelium (hFTE) is the site of fertilization, early embryo development, and the origin of most high-grade serous ovarian cancers (HGSOCs). Little is known about the content and functions of hFTE-derived small extracellular vesicles (sEVs) due to the limitations of biomaterials and proper culture methods. We have established a microfluidic platform to culture hFTE for EV collection with adequate yield for mass spectrometry-based proteomic profiling, and reported 295 common hFTE sEV proteins for the first time. These proteins are associated with exocytosis, neutrophil degranulation, and wound healing, and some are crucial for fertilization processes. In addition, by correlating sEV protein profiles with hFTE tissue transcripts characterized using GeoMx® Cancer Transcriptome Atlas, spatial transcriptomics analysis revealed cell-type-specific transcripts of hFTE that encode sEVs proteins, among which, FLNA, TUBB, JUP, and FLNC were differentially expressed in secretory cells, the precursor cells for HGSOC. Our study provides insights into the establishment of the baseline proteomic profile of sEVs derived from hFTE tissue, and its correlation with hFTE lineage-specific transcripts, which can be used to evaluate whether the fallopian tube shifts its sEV cargo during ovarian cancer carcinogenesis and the role of sEV proteins in fallopian tube reproductive functions.

12.
Kans J Med ; 15: 273-277, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36042840

RESUMO

Introduction: Colon cancer impacts the lives of Kansans and those across the United States. Epidermal growth factor receptor (EGFR) inhibitors, such as panitumumab and cetuximab, have gained popularity as first-line treatment for stage 4 colon cancer despite their toxicities and have been used by clinicians in later lines of therapy. EGFR inhibitors have been proven to be an efficacious first-line treatment for stage 4 colon cancer, but no study has investigated outcomes comparing EGFR inhibitors as first-line treatment to its use as second- or third-line treatment. This study investigated EGFR inhibitor therapy estimated overall survival when used as first-, second-, and third-line treatment for stage 4 colon cancer. Methods: A retrospective review was done for patients with stage 4 colon cancer who underwent EGFR inhibitor treatment at a large academic center from November 2007 to August 2021. The patients were stratified into five groups by the line in which they received the EGFR inhibitor treatment. A log-rank test was used to analyze the groups, and the median survival for each group was determined. Results: A total of 68 patients were reviewed; 18 received first-line, 23 received second-line, 18 received third-line, 6 received fourth-line, and 3 received sixth-line treatment with an EGFR inhibitor. Fourth- and sixth-line therapies were excluded due to small patient size. There was no significant difference in estimated survival time between any of the lines. Median survival of the therapies was found. Conclusions: There was no statistical difference in survival between the first-, second-, or third-line groups, which may provide justification for its use as a second- or third-line therapy.

13.
Semin Arthritis Rheum ; 56: 152056, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35785666

RESUMO

OBJECTIVE: Methotrexate (MTX) remains the first-choice disease-modifying therapy in rheumatoid arthritis (RA). However, clinical response is variable, and no reliable predictive biomarkers of efficacy currently exist. In this study, plasma metabolomic profiling is evaluated as a tool to identify pretreatment biomarkers of MTX response in RA. METHODS: Plasma collected from RA patients initiating MTX therapy (n = 20) were analyzed by metabolomic profiling totaling 648 identified metabolites. Pretreatment metabolomic profiles were compared based on clinical response after 16-weeks of MTX therapy. Clinical response to MTX was defined by a clinically meaningful reduction in disease activity score in 28 joints (DAS28-ESR) of greater than 1.2. RESULTS: Pretreatment plasma levels of 19 metabolites were found to differ (p < 0.05) between RA patients based on response to MTX at 16-weeks. Spearman's correlation of pretreatment plasma metabolite levels with change in DAS28-ESR over the treatment period further supported three of the identified metabolites as associated with MTX response (p < 0.05). The identified metabolite levels were all found to be lower in RA patients responsive to MTX but were not found to be intercorrelated. Receiver operating characteristic analysis of each of the identified metabolites, alone or in combination, demonstrated an excellent discrimination between responders and non-responders based on pretreatment plasma levels of nornicotine (AUC = 0.84), N-methylisoleucine (AUC = 0.82), 2,3-dihydroxybutanoic acid (AUC = 0.82), and a combination biomarker panel score (AUC = 0.98). CONCLUSION: Pretreatment plasma metabolomic profiling identified multiple metabolites associated with early response to MTX therapy in RA and represents a promising approach for the identification of clinical biomarkers of MTX response in RA.


Assuntos
Antirreumáticos , Artrite Reumatoide , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Biomarcadores , Quimioterapia Combinada , Humanos , Metotrexato/uso terapêutico , Resultado do Tratamento
14.
Catheter Cardiovasc Interv ; 100(3): 378-386, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35819134

RESUMO

OBJECTIVES: To identify angiographic predictors of aberrant left circumflex artery (LCx) by comparing left main (LM) length and bifurcation angle between patients with aberrant LCx and normal anatomy. BACKGROUND: Failure to recognize aberrant LCx during a cardiac catheterization may hamper correct diagnosis, delay intervention in acute coronary syndromes, and result in increased contrast volume, radiation exposure, and infarct size. METHODS: We retrospectively analyzed angiograms of aberrant LCx patients and normal anatomy matched controls, in three-participating centers. LM-length, bifurcation angle between the left anterior descending (LAD) and the first non-LAD branch of the LM, and procedural data were compared. RESULTS: Between 2003 and 2020, 136 patients with aberrant LCx and 135 controls were identified. More catheters (2.4 ± 0.6 vs. 2.2 ± 0.9, p = 0.009), larger contrast volumes (169 ± 94 ml vs. 129 ± 68 ml, p < 0.0005), and prolonged fluoroscopy time (652.9 ± 623.7 s vs. 393.1 ± 332.1 s, p < 0.0005), were required in the aberrant LCx-group compared with controls. Patients with aberrant LCx had a longer LM-length and a more acute bifurcation angle, both in caudal and cranial views, compared with controls (24.7 ± 8.1 vs. 10.8 ± 4.5 mm, p < 0.0005 and 26.7 ± 7.4 vs. 12 ± 5.5 mm, p < 0.0005, respectively, and 45.2° ± 12° vs. 88.8° ± 23°, p < 0.0005 and 51.9° ± 21° vs. 68.2° ± 28.3°, p < 0.0005, respectively). In ROC analysis, LM-length showed the best diagnostic accuracy for detecting aberrant LCx. In multiple logistic regression analysis, a cranially measured LM-length > 17.7 mm was associated with a 5.3 times greater probability of predicting aberrant LCx [95% CI (3.4-8.1), p < 0.0001]. CONCLUSIONS: Our study suggests that a long LM-length and an acute bifurcation angle can indicate the presence of aberrant LCx. We present a practical algorithm for its rapid identification.


Assuntos
Doença da Artéria Coronariana , Malformações Vasculares , Cateterismo Cardíaco/efeitos adversos , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Vasos Coronários/diagnóstico por imagem , Humanos , Estudos Retrospectivos , Resultado do Tratamento
15.
Biom J ; 64(6): 1023-1039, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35561036

RESUMO

Hepatocellular carcinoma (HCC) is the most common primary cancer of the liver. Finding new biomarkers for its early detection is of high clinical importance. As with many other diseases, cancer has a progressive nature. In cancer biomarker studies, it is often the case that the true disease status of the recruited individuals exhibits more than two classes. The receiver operating characteristic (ROC) surface is a well-known statistical tool for assessing the biomarkers' discriminatory ability in trichotomous settings. The volume under the ROC surface (VUS) is an overall measure of the discriminatory ability of a marker. In practice, clinicians are often in need of cutoffs for decision-making purposes. A popular approach for computing such cutoffs is the Youden index and its recent three-class generalization. A drawback of such a method is that it treats the data in a pairwise fashion rather than consider all the data simultaneously. The use of the minimized Euclidean distance from the perfection corner to the ROC surface (also known as closest to perfection method) is an alternative to the Youden index that may be preferable in some settings. When such a method is employed, there is a need for inferences around the resulting true class rates/fractions that correspond to the optimal operating point. In this paper, we provide an inferential framework for the derivation of marginal confidence intervals (CIs) and joint confidence spaces (CSs) around the corresponding true class fractions, when dealing with trichotomous settings. We explore parametric and nonparametric approaches for the construction of such CIs and CSs. We evaluate our approaches through extensive simulations and apply them to a real data set that refers to HCC patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Biomarcadores , Carcinoma Hepatocelular/diagnóstico , Humanos , Neoplasias Hepáticas/diagnóstico , Curva ROC
16.
Stat Med ; 41(18): 3527-3546, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35543227

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is the most deadly cancer and currently there is strong clinical interest in novel biomarkers that contribute to its early detection. Assessing appropriately the accuracy of such biomarkers is a crucial issue and often one needs to take into account that many assays include biospecimens of individuals coming from three groups: healthy, chronic pancreatitis, and PDAC. The ROC surface is an appropriate tool for assessing the overall accuracy of a marker employed under such trichotomous settings. A decision/classification rule is often based on the so-called Youden index and its three-dimensional generalization. However, both the clinical and the statistical literature have not paid the necessary attention to the underlying false classification (FC) rates that are of equal or even greater importance. In this article we provide a framework to make inferences around all classification rates as well as comparisons. We explore the trinormal model, flexible models based on power transformations, and robust non-parametric alternatives. We provide a full framework for the construction of confidence intervals, regions, and spaces for joint inferences or for clinically meaningful points of interest. We further discuss the implications of costs related to different FCs. We evaluate our approaches through extensive simulations and illustrate them using data from a recent PDAC study conducted at the MD Anderson Cancer Center.


Assuntos
Neoplasias Pancreáticas , Biomarcadores , Biomarcadores Tumorais , Humanos , Neoplasias Pancreáticas/diagnóstico , Curva ROC , Neoplasias Pancreáticas
18.
Neuroscience ; 468: 53-67, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34107347

RESUMO

Inflammation plays a key role in the progression and maintenance of chronic pain, which impacts the lives of millions of Americans. Despite growing evidence that chronic pain can be improved by treating underlying inflammation, successful treatments are lacking and pharmaceutical interventions are limited due to drug side effects. Here we are testing whether a 'healthy human' diet (HHD), with or without anti-inflammatory components (HHAID), improves pain-like behaviors in a preclinical model of chronic widespread hypersensitivity induced by neonatal maternal separation (NMS). The HHD and HHAID are isocaloric and macronutrient-matched, have a low glycemic index, and fat content (35 kcal%) that is high in omega-3 fatty acids, while only the HHAID includes a combination of key anti-inflammatory compounds, at clinically relevant doses. Mice on these diets were compared to mice on a control diet with a macronutrient composition commonly used in rodents (20% protein, 70% carbohydrate, 10% fat). Our results demonstrate a benefit of the HHAID on pain-like behaviors in both male and female mice, despite increased caloric intake, adiposity, and weight gain. In female mice, HHAID specifically increased measures of metabolic syndrome and inflammation compared to the HHD and control diet groups. Male mice were susceptible to worsening metabolic measures on both the HHAID and HHD. This work highlights important sexual dimorphic outcomes related to early life stress exposure and dietary interventions, as well as a potential disconnect between improvements in pain-like behaviors and metabolic measures.


Assuntos
Ácidos Graxos Ômega-3 , Hiperalgesia , Animais , Anti-Inflamatórios , Dieta , Dieta Hiperlipídica/efeitos adversos , Feminino , Hiperalgesia/tratamento farmacológico , Masculino , Privação Materna , Camundongos
19.
Protein Sci ; 30(9): 1833-1853, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34076313

RESUMO

When amino acids vary during evolution, the outcome can be functionally neutral or biologically-important. We previously found that substituting a subset of nonconserved positions, "rheostat" positions, can have surprising effects on protein function. Since changes at rheostat positions can facilitate functional evolution or cause disease, more examples are needed to understand their unique biophysical characteristics. Here, we explored whether "phylogenetic" patterns of change in multiple sequence alignments (such as positions with subfamily specific conservation) predict the locations of functional rheostat positions. To that end, we experimentally tested eight phylogenetic positions in human liver pyruvate kinase (hLPYK), using 10-15 substitutions per position and biochemical assays that yielded five functional parameters. Five positions were strongly rheostatic and three were non-neutral. To test the corollary that positions with low phylogenetic scores were not rheostat positions, we combined these phylogenetic positions with previously-identified hLPYK rheostat, "toggle" (most substitution abolished function), and "neutral" (all substitutions were like wild-type) positions. Despite representing 428 variants, this set of 33 positions was poorly statistically powered. Thus, we turned to the in vivo phenotypic dataset for E. coli lactose repressor protein (LacI), which comprised 12-13 substitutions at 329 positions and could be used to identify rheostat, toggle, and neutral positions. Combined hLPYK and LacI results show that positions with strong phylogenetic patterns of change are more likely to exhibit rheostat substitution outcomes than neutral or toggle outcomes. Furthermore, phylogenetic patterns were more successful at identifying rheostat positions than were co-evolutionary or eigenvector centrality measures of evolutionary change.


Assuntos
Substituição de Aminoácidos , DNA/química , Proteínas de Escherichia coli/química , Evolução Molecular , Repressores Lac/química , Piruvato Quinase/química , Difosfato de Adenosina/química , Difosfato de Adenosina/metabolismo , Sítios de Ligação , Clonagem Molecular , Biologia Computacional/métodos , DNA/genética , DNA/metabolismo , Escherichia coli/classificação , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Humanos , Cinética , Repressores Lac/genética , Repressores Lac/metabolismo , Modelos Moleculares , Mutação , Fosfoenolpiruvato/química , Fosfoenolpiruvato/metabolismo , Filogenia , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Piruvato Quinase/genética , Piruvato Quinase/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Relação Estrutura-Atividade , Termodinâmica
20.
Stat Med ; 40(20): 4522-4539, 2021 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-34080733

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive type of cancer with a 5-year survival rate of less than 5%. As in many other diseases, its diagnosis might involve progressive stages. It is common that in biomarker studies referring to PDAC, recruitment involves three groups: healthy individuals, patients that suffer from chronic pancreatitis, and PDAC patients. Early detection and accurate classification of the state of the disease are crucial for patients' successful treatment. ROC analysis is the most popular way to evaluate the performance of a biomarker and the Youden index is commonly employed for cutoff derivation. The so-called generalized Youden index has a drawback in the three-class case of not accommodating the full data set when estimating the optimal cutoffs. In this article, we explore the use of the Euclidean distance of the ROC to the perfection corner for the derivation of cutoffs in trichotomous settings. We construct an inferential framework that involves both parametric and nonparametric techniques. Our methods can accommodate the full information of a given data set and thus provide more accurate estimates in terms of the decision-making cutoffs compared with a Youden-based strategy. We evaluate our approaches through extensive simulations and illustrate them on a PDAC biomarker study.


Assuntos
Neoplasias Pancreáticas , Biomarcadores , Intervalos de Confiança , Humanos , Neoplasias Pancreáticas/diagnóstico , Curva ROC
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