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1.
bioRxiv ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38496571

RESUMO

Self-supervised learning (SSL) automates the extraction and interpretation of histopathology features on unannotated hematoxylin-and-eosin-stained whole-slide images (WSIs). We trained an SSL Barlow Twins-encoder on 435 TCGA colon adenocarcinoma WSIs to extract features from small image patches. Leiden community detection then grouped tiles into histomorphological phenotype clusters (HPCs). HPC reproducibility and predictive ability for overall survival was confirmed in an independent clinical trial cohort (N=1213 WSIs). This unbiased atlas resulted in 47 HPCs displaying unique and sharing clinically significant histomorphological traits, highlighting tissue type, quantity, and architecture, especially in the context of tumor stroma. Through in-depth analysis of these HPCs, including immune landscape and gene set enrichment analysis, and association to clinical outcomes, we shed light on the factors influencing survival and responses to treatments like standard adjuvant chemotherapy and experimental therapies. Further exploration of HPCs may unveil new insights and aid decision-making and personalized treatments for colon cancer patients.

2.
Breast Cancer Res ; 26(1): 17, 2024 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-38287342

RESUMO

BACKGROUND: Histological grade is a well-known prognostic factor that is routinely assessed in breast tumours. However, manual assessment of Nottingham Histological Grade (NHG) has high inter-assessor and inter-laboratory variability, causing uncertainty in grade assignments. To address this challenge, we developed and validated a three-level NHG-like deep learning-based histological grade model (predGrade). The primary performance evaluation focuses on prognostic performance. METHODS: This observational study is based on two patient cohorts (SöS-BC-4, N = 2421 (training and internal test); SCAN-B-Lund, N = 1262 (test)) that include routine histological whole-slide images (WSIs) together with patient outcomes. A deep convolutional neural network (CNN) model with an attention mechanism was optimised for the classification of the three-level histological grading (NHG) from haematoxylin and eosin-stained WSIs. The prognostic performance was evaluated by time-to-event analysis of recurrence-free survival and compared to clinical NHG grade assignments in the internal test set as well as in the fully independent external test cohort. RESULTS: We observed effect sizes (hazard ratio) for grade 3 versus 1, for the conventional NHG method (HR = 2.60 (1.18-5.70 95%CI, p-value = 0.017)) and the deep learning model (HR = 2.27, 95%CI 1.07-4.82, p-value = 0.033) on the internal test set after adjusting for established clinicopathological risk factors. In the external test set, the unadjusted HR for clinical NHG 2 versus 1 was estimated to be 2.59 (p-value = 0.004) and clinical NHG 3 versus 1 was estimated to be 3.58 (p-value < 0.001). For predGrade, the unadjusted HR for predGrade 2 versus 1 HR = 2.52 (p-value = 0.030), and 4.07 (p-value = 0.001) for preGrade 3 versus 1 was observed in the independent external test set. In multivariable analysis, HR estimates for neither clinical NHG nor predGrade were found to be significant (p-value > 0.05). We tested for differences in HR estimates between NHG and predGrade in the independent test set and found no significant difference between the two classification models (p-value > 0.05), confirming similar prognostic performance between conventional NHG and predGrade. CONCLUSION: Routine histopathology assessment of NHG has a high degree of inter-assessor variability, motivating the development of model-based decision support to improve reproducibility in histological grading. We found that the proposed model (predGrade) provides a similar prognostic performance as clinical NHG. The results indicate that deep CNN-based models can be applied for breast cancer histological grading.


Assuntos
Neoplasias da Mama , Aprendizado Profundo , Feminino , Humanos , Neoplasias da Mama/patologia , Prognóstico , Reprodutibilidade dos Testes
3.
Ann Neurol ; 93(5): 1023-1028, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36897287

RESUMO

OBJECTIVE: This study was undertaken to examine the association between montelukast use, ß2-adrenoreceptor (ß2AR) agonist use, and later Parkinson disease (PD). METHODS: We ascertained use of ß2AR agonists (430,885 individuals) and montelukast (23,315 individuals) from July 1, 2005 to June 30, 2007, and followed 5,186,886 PD-free individuals from July 1, 2007 to December 31, 2013 for incident PD diagnosis. We estimated hazard ratios and 95% confidence intervals using Cox regressions. RESULTS: We observed 16,383 PD cases during on average 6.1 years of follow-up. Overall, use of ß2AR agonists and montelukast were not related to PD incidence. A 38% lower PD incidence was noted among high-dose montelukast users when restricted to PD registered as the primary diagnosis. INTERPRETATION: Overall, our data do not support inverse associations between ß2AR agonists, montelukast, and PD. The prospect of lower PD incidence with high-dose montelukast exposure warrants further investigation, especially with adjustment for high-quality data on smoking. ANN NEUROL 2023;93:1023-1028.


Assuntos
Doença de Parkinson , Quinolinas , Humanos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/epidemiologia , Acetatos/efeitos adversos , Ciclopropanos , Quinolinas/efeitos adversos
4.
iScience ; 25(7): 104663, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35832894

RESUMO

Routine transrectal ultrasound-guided systematic prostate biopsy only samples a small volume of the prostate and tumors between biopsy cores can be missed, leading to low sensitivity to detect clinically relevant prostate cancers (PCa). Deep learning may enable detection of PCa despite benign biopsies. We included 14,354 hematoxylin-eosin stained benign prostate biopsies from 1,508 men in two groups: men without established PCa diagnosis and men with at least one core biopsy diagnosed with PCa. A 10-Convolutional Neural Network ensemble was optimized to distinguish benign biopsies from benign men or patients with PCa. Area under the receiver operating characteristic curve was estimated at 0.739 (bootstrap 95% CI:0.682-0.796) on man level in the held-out test set. At the specificity of 0.90, the model sensitivity was 0.348. The proposed model can detect men with risk of missed PCa and has the potential to reduce false negatives and to indicate men who could benefit from rebiopsies.

5.
Aliment Pharmacol Ther ; 51(11): 1022-1030, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32319125

RESUMO

BACKGROUND: The vagus nerve provides essential parasympathetic innervation to the gastrointestinal system and is known to have anti-inflammatory properties. AIMS: To explore the relationship between vagotomy and the risk of inflammatory bowel disease (IBD) and its major categories: Crohn's disease (CD) and ulcerative colitis (UC). METHODS: A matched cohort comprising 15 637 patients undergoing vagotomy was identified through the Swedish Patient Register from 1964 to 2010. Each vagotomised patient was matched for birth year and gender with 40 nonvagotomised individuals on the date of vagotomy. We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for IBD using flexible parametric models adjusted for matching variables, year of vagotomy, birth country, chronic obstructive pulmonary disease and comorbidity index. RESULTS: We observed 119 (0.8%) patients with vagotomy developed IBD compared to 3377 (0.5%) IBD cases in nonvagotomised individuals. The crude incidence of IBD (per 1000 person-years) was 0.38 for vagotomised patients and 0.25 for nonvagotomised individuals. We observed a time-dependent elevated risk of IBD associated with vagotomy, for instance, the HR (95% CI) was 1.80 (1.40-2.31) at year 5 and 1.49 (1.14-1.96) at year 10 post-vagotomy. The association appeared to be stronger for truncal than selective vagotomy and limited to CD (HR was 3.63 [1.94-6.80] for truncal and 2.06 [1.49-2.84] for selective vagotomy) but not UC (1.36 [0.71-2.62] for truncal and 1.25 [0.95-1.63] for selective vagotomy). CONCLUSIONS: We found a positive association between vagotomy and later IBD, particularly for CD. The finding indirectly underlines the beneficial role of the vagal tone in IBD.


Assuntos
Doenças Inflamatórias Intestinais/etiologia , Complicações Pós-Operatórias/etiologia , Vagotomia/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Estudos de Coortes , Colite Ulcerativa/epidemiologia , Colite Ulcerativa/etiologia , Doença de Crohn/epidemiologia , Doença de Crohn/etiologia , Feminino , Humanos , Incidência , Doenças Inflamatórias Intestinais/epidemiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Sistema de Registros , Fatores de Risco , Suécia/epidemiologia , Vagotomia/estatística & dados numéricos
6.
Rev. panam. salud pública ; 38(6): 515-532, nov.-dic. 2015. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-788111

RESUMO

Aplicamos un método estructurado para evaluar si los fumadores activos a los que se les mostraban advertencias gráficas en los paquetes de cigarrillos tenían una probabilidad mayor de abandonar el hábito, reducir el consumo de cigarrillos o intentar dejar de fumar por comparación con fumadores no expuestos. Seleccionamos 21 artículos de entre casi 2500 publicados entre 1993 y 2013, dando prioridad a la cobertura sobre la pertinencia o la calidad porque preveíamos encontrar muy pocos estudios con resultados comportamentales. Observamos una heterogeneidad muy grande entre los estudios, una calidad metodológica deficiente o muy deficiente y resultados por lo general nulos o contradictorios con respecto a cualquier desenlace explorado. Los datos científicos a favor o en contra del uso de las advertencias gráficas son insuficientes, lo cual hace sospechar que cualquier efecto de estas sobre el comportamiento sería moderado. La determinación del efecto individual de las advertencias gráficas sobre el comportamiento requiere de estudios con diseños metodológicos sólidos y períodos de seguimiento más largos.


We used a structured approach to assess whether active smokers presented with pictorial warnings on cigarette packages (PWCP) had a higher probability of quitting, reducing, and attempting to quit smoking than did unexposed smokers. We identified 21 articles from among nearly 2500 published between 1993 and 2013, prioritizing coverage over relevance or quality because we expected to find only a few studies with behavioral outcomes. We found very large heterogeneity across studies, poor or very poor methodological quality, and generally null or conflicting findings for any explored outcome. The evidence for or against the use of PWCP is insufficient, suggesting that any effect of PWCP on behavior would be modest. Determining the single impact of PWCP on behavior requires studies with strong methodological designs and longer follow-up periods.


Assuntos
Prevenção do Hábito de Fumar/métodos , Prevenção do Hábito de Fumar/provisão & distribuição , Prevenção do Hábito de Fumar
7.
Rev Panam Salud Publica ; 38(6): 515-32, 2015 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-27440101

RESUMO

We used a structured approach to assess whether active smokers presented with pictorial warnings on cigarette packages (PWCP) had a higher probability of quitting, reducing, and attempting to quit smoking than did unexposed smokers. We identified 21 articles from among nearly 2500 published between 1993 and 2013, prioritizing coverage over relevance or quality because we expected to find only a few studies with behavioral outcomes. We found very large heterogeneity across studies, poor or very poor methodological quality, and generally null or conflicting findings for any explored outcome. The evidence for or against the use of PWCP is insufficient, suggesting that any effect of PWCP on behavior would be modest. Determining the single impact of PWCP on behavior requires studies with strong methodological designs and longer follow-up periods.


Assuntos
Comportamentos Relacionados com a Saúde , Fumar , Humanos , Rotulagem de Produtos , Produtos do Tabaco , Tabagismo
8.
Am J Public Health ; 104(10): e11-30, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25122019

RESUMO

We used a structured approach to assess whether active smokers presented with pictorial warnings on cigarette packages (PWCP) had a higher probability of quitting, reducing, and attempting to quit smoking than did unexposed smokers. We identified 21 articles from among nearly 2500 published between 1993 and 2013, prioritizing coverage over relevance or quality because we expected to find only a few studies with behavioral outcomes. We found very large heterogeneity across studies, poor or very poor methodological quality, and generally null or conflicting findings for any explored outcome. The evidence for or against the use of PWCP is insufficient, suggesting that any effect of PWCP on behavior would be modest. Determining the single impact of PWCP on behavior requires studies with strong methodological designs and longer follow-up periods.


Assuntos
Rotulagem de Produtos/métodos , Abandono do Hábito de Fumar/psicologia , Fumar/psicologia , Produtos do Tabaco , Humanos , Intenção , Motivação
9.
Biol Trace Elem Res ; 119(2): 128-36, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17916936

RESUMO

The present study was designed to investigate the effects of various cadmium concentrations on porcine growth hormone (GH) secretion in serum and cultured pituitary cells and to explore the possible mechanisms of cadmium toxicity. In feeding trial, 192 barrows (Duroc x Landrace x Yorkshire), with similar initial body weights, were randomly divided into four different treatment groups with three replicates for each treatment. The diets were supplemented for 83 days with 0, 0.5, 5.0, and 10.0 mg/kg cadmium (as CdCl2). For the cell culture trial, dispersed pituitary cells were incubated with graded doses of cadmium (0, 5, 10, 15, or 20 microM) for 24 h. Pigs treated with 10 mg/kg cadmium had significantly decreased serum GH content. 3-(4,5-dimethyl-2-yl)-2,5-diphenyl tetrazolium bromide assay showed that Cd toxicity was dose-dependent. Cell viability was reduced to 50% at 15 microM concentration. Administration of cadmium significantly reduced GH secretion, whereas cellular NO content and inducible nitric oxide synthase activity increased to a certain extent. These findings suggest that the decrease of GH might be related to NO production and to a change of NO signal pathway caused by cadmium.


Assuntos
Intoxicação por Cádmio/metabolismo , Hormônio do Crescimento/sangue , Óxido Nítrico/biossíntese , Hipófise/metabolismo , Animais , Cloreto de Cádmio/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Hormônio do Crescimento/metabolismo , Masculino , Óxido Nítrico Sintase Tipo II/metabolismo , Suínos
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