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1.
JMIR Diabetes ; 9: e52688, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488828

RESUMO

BACKGROUND: Digital health programs provide individualized support to patients with chronic diseases and their effectiveness is measured by the extent to which patients achieve target individual clinical outcomes and the program's ability to sustain patient engagement. However, patient dropout and inequitable intervention delivery strategies, which may unintentionally penalize certain patient subgroups, represent challenges to maximizing effectiveness. Therefore, methodologies that optimize the balance between success factors (achievement of target clinical outcomes and sustained engagement) equitably would be desirable, particularly when there are resource constraints. OBJECTIVE: Our objectives were to propose a model for digital health program resource management that accounts jointly for the interaction between individual clinical outcomes and patient engagement, ensures equitable allocation as well as allows for capacity planning, and conducts extensive simulations using publicly available data on type 2 diabetes, a chronic disease. METHODS: We propose a restless multiarmed bandit (RMAB) model to plan interventions that jointly optimize long-term engagement and individual clinical outcomes (in this case measured as the achievement of target healthy glucose levels). To mitigate the tendency of RMAB to achieve good aggregate performance by exacerbating disparities between groups, we propose new equitable objectives for RMAB and apply bilevel optimization algorithms to solve them. We formulated a model for the joint evolution of patient engagement and individual clinical outcome trajectory to capture the key dynamics of interest in digital chronic disease management programs. RESULTS: In simulation exercises, our optimized intervention policies lead to up to 10% more patients reaching healthy glucose levels after 12 months, with a 10% reduction in dropout compared to standard-of-care baselines. Further, our new equitable policies reduce the mean absolute difference of engagement and health outcomes across 6 demographic groups by up to 85% compared to the state-of-the-art. CONCLUSIONS: Planning digital health interventions with individual clinical outcome objectives and long-term engagement dynamics as considerations can be both feasible and effective. We propose using an RMAB sequential decision-making framework, which may offer additional capabilities in capacity planning as well. The integration of an equitable RMAB algorithm further enhances the potential for reaching equitable solutions. This approach provides program designers with the flexibility to switch between different priorities and balance trade-offs across various objectives according to their preferences.

2.
J Clin Invest ; 132(17)2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35819852

RESUMO

An extreme chronic wound tissue microenvironment causes epigenetic gene silencing. An unbiased whole-genome methylome was studied in the wound-edge tissue of patients with chronic wounds. A total of 4,689 differentially methylated regions (DMRs) were identified in chronic wound-edge skin compared with unwounded human skin. Hypermethylation was more frequently observed (3,661 DMRs) in the chronic wound-edge tissue compared with hypomethylation (1,028 DMRs). Twenty-six hypermethylated DMRs were involved in epithelial-mesenchymal transition (EMT). Bisulfite sequencing validated hypermethylation of a predicted specific upstream regulator TP53. RNA-Seq analysis was performed to qualify findings from methylome analysis. Analysis of the downregulated genes identified the TP53 signaling pathway as being significantly silenced. Direct comparison of hypermethylation and downregulated genes identified 4 genes, ADAM17, NOTCH, TWIST1, and SMURF1, that functionally represent the EMT pathway. Single-cell RNA-Seq studies revealed that these effects on gene expression were limited to the keratinocyte cell compartment. Experimental murine studies established that tissue ischemia potently induces wound-edge gene methylation and that 5'-azacytidine, inhibitor of methylation, improved wound closure. To specifically address the significance of TP53 methylation, keratinocyte-specific editing of TP53 methylation at the wound edge was achieved by a tissue nanotransfection-based CRISPR/dCas9 approach. This work identified that reversal of methylation-dependent keratinocyte gene silencing represents a productive therapeutic strategy to improve wound closure.


Assuntos
Metilação de DNA , Transição Epitelial-Mesenquimal , Animais , Ilhas de CpG , DNA , Epigênese Genética , Transição Epitelial-Mesenquimal/genética , Humanos , Camundongos , Ubiquitina-Proteína Ligases/genética
3.
Proc Natl Acad Sci U S A ; 117(41): 25904-25910, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-32973089

RESUMO

As the COVID-19 pandemic continues, formulating targeted policy interventions that are informed by differential severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission dynamics will be of vital importance to national and regional governments. We develop an individual-level model for SARS-CoV-2 transmission that accounts for location-dependent distributions of age, household structure, and comorbidities. We use these distributions together with age-stratified contact matrices to instantiate specific models for Hubei, China; Lombardy, Italy; and New York City, United States. Using data on reported deaths to obtain a posterior distribution over unknown parameters, we infer differences in the progression of the epidemic in the three locations. We also examine the role of transmission due to particular age groups on total infections and deaths. The effect of limiting contacts by a particular age group varies by location, indicating that strategies to reduce transmission should be tailored based on population-specific demography and social structure. These findings highlight the role of between-population variation in formulating policy interventions. Across the three populations, though, we find that targeted "salutary sheltering" by 50% of a single age group may substantially curtail transmission when combined with the adoption of physical distancing measures by the rest of the population.


Assuntos
Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Modelos Estatísticos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Betacoronavirus/fisiologia , COVID-19 , China/epidemiologia , Controle de Doenças Transmissíveis/legislação & jurisprudência , Controle de Doenças Transmissíveis/métodos , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/patologia , Humanos , Itália/epidemiologia , Cidade de Nova Iorque/epidemiologia , Pneumonia Viral/epidemiologia , Pneumonia Viral/patologia , SARS-CoV-2
4.
Thyroid ; 28(6): 748-754, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29768105

RESUMO

BACKGROUND: The BRAFV600E mutation is the most common driver in papillary thyroid carcinoma (PTC) tumors. In recent years, gene fusions have also been recognized as important drivers of cancer in PTC. Previous studies have suggested that thyroid tumors with fusion genes frequently display an aggressive course. These observations prompted further exploration of gene fusions in PTC tumors. The aim was to search for previously unrecognized gene fusions using thyroid tissue samples from PTC patients. METHODS: Gene fusions were analyzed in RNA sequencing data obtained from 12 PTC tumors and paired unaffected thyroid tissue samples. Candidate fusions were further filtered and validated using reverse transcriptase polymerase chain reaction, Sanger sequencing, and fluorescence in situ hybridization. An Ohio cohort of 148 PTC tumor samples was screened for a LMO7-BRAF fusion and the BRAFV600E mutation. Functional assays were performed to assess the LMO7-BRAF fusion. RESULTS: Two coding fusions (CCDC6-RET and LMO7-BRAF) were found in one tumor sample each. The novel LMO7-BRAF fusion was validated by reverse transcriptase polymerase chain reaction and fluorescence in situ hybridization. The LMO7-BRAF fusion was a recurrent somatic alteration with a frequency of 2.0% (3/148) in PTC tumors, while the BRAFV600E point mutation was found in 63.5% (94/148) of tumors. Enforced expression of LMO7-BRAF fusion protein stimulated endogenous ERK1/2 phosphorylation and promoted anchorage independent cell growth to an extent similar to BRAFV600E. CONCLUSIONS: A novel fusion gene, LMO7-BRAF, was identified in PTC tumors. The results indicate that the LMO7-BRAF fusion behaves as an oncogenic alteration. This observation expands the spectrum of fusion genes involving kinases in thyroid cancer.


Assuntos
Proteínas com Domínio LIM/genética , Proteínas de Fusão Oncogênica/genética , Proteínas Proto-Oncogênicas B-raf/genética , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/patologia , Fatores de Transcrição/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Carcinoma Papilar/genética , Carcinoma Papilar/patologia , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Mutação , Células NIH 3T3 , Recidiva Local de Neoplasia , Fosforilação , Mutação Puntual , RNA/análise , Análise de Sequência de RNA , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Adulto Jovem
5.
BMC Genomics ; 19(1): 139, 2018 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-29439649

RESUMO

BACKGROUND: Gene fusions often occur in cancer cells and in some cases are the main driver of oncogenesis. Correct identification of oncogenic gene fusions thus has implications for targeted cancer therapy. Recognition of this potential has led to the development of a myriad of sequencing-based fusion detection tools. However, given the same input, many of these detectors will find different fusion points or claim different sets of supporting data. Furthermore, the rate at which these tools falsely detect fusion events in data varies greatly. This discrepancy between tools underscores the fact that computation algorithms still cannot perfectly evaluate evidence; especially when provided with small amounts of supporting data as is typical in fusion detection. We assert that when evidence is provided in an easily digestible form, humans are more proficient in identifying true positives from false positives. RESULTS: We have developed a web tool that, given the genomic coordinates of a candidate fusion breakpoint, will extract fusion and non-fusion reads adjacent to the fusion point from partner transcripts, and color code reads by transcript origin and read orientation for ease of intuitive inspection by the user. Fusion partner transcript read alignments are performed using a novel variant of the Smith-Waterman algorithm. CONCLUSIONS: Combined with dynamic filtering parameters, the visualization provided by our tool introduces a powerful new investigative step that allows researchers to comprehensively evaluate fusion evidence. Additionally, this allows quick identification of false positives that may deceive most fusion detectors, thus eliminating unnecessary gene fusion validation. We apply our visualization tool to publicly available datasets and provide examples of true as well as false positives reported by open source fusion detection tools.


Assuntos
Biologia Computacional/métodos , Neoplasias/genética , Fusão Oncogênica , Proteínas de Fusão Oncogênica/genética , Software , Algoritmos , Genômica/métodos , Humanos , Armazenamento e Recuperação da Informação
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