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1.
N Engl J Med ; 385(16): 1451-1461, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34449189

RESUMO

BACKGROUND: Sodium-glucose cotransporter 2 inhibitors reduce the risk of hospitalization for heart failure in patients with heart failure and a reduced ejection fraction, but their effects in patients with heart failure and a preserved ejection fraction are uncertain. METHODS: In this double-blind trial, we randomly assigned 5988 patients with class II-IV heart failure and an ejection fraction of more than 40% to receive empagliflozin (10 mg once daily) or placebo, in addition to usual therapy. The primary outcome was a composite of cardiovascular death or hospitalization for heart failure. RESULTS: Over a median of 26.2 months, a primary outcome event occurred in 415 of 2997 patients (13.8%) in the empagliflozin group and in 511 of 2991 patients (17.1%) in the placebo group (hazard ratio, 0.79; 95% confidence interval [CI], 0.69 to 0.90; P<0.001). This effect was mainly related to a lower risk of hospitalization for heart failure in the empagliflozin group. The effects of empagliflozin appeared consistent in patients with or without diabetes. The total number of hospitalizations for heart failure was lower in the empagliflozin group than in the placebo group (407 with empagliflozin and 541 with placebo; hazard ratio, 0.73; 95% CI, 0.61 to 0.88; P<0.001). Uncomplicated genital and urinary tract infections and hypotension were reported more frequently with empagliflozin. CONCLUSIONS: Empagliflozin reduced the combined risk of cardiovascular death or hospitalization for heart failure in patients with heart failure and a preserved ejection fraction, regardless of the presence or absence of diabetes. (Funded by Boehringer Ingelheim and Eli Lilly; EMPEROR-Preserved ClinicalTrials.gov number, NCT03057951).


Assuntos
Compostos Benzidrílicos/administração & dosagem , Doenças Cardiovasculares/prevenção & controle , Glucosídeos/administração & dosagem , Insuficiência Cardíaca/tratamento farmacológico , Inibidores do Transportador 2 de Sódio-Glicose/administração & dosagem , Volume Sistólico , Adulto , Compostos Benzidrílicos/efeitos adversos , Doenças Cardiovasculares/mortalidade , Doença Crônica , Método Duplo-Cego , Feminino , Glucosídeos/efeitos adversos , Insuficiência Cardíaca/fisiopatologia , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos
2.
Gastrointest Endosc ; 95(2): 339-348, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34508767

RESUMO

BACKGROUND AND AIMS: The diagnosis and characterization of biliary strictures (BSs) is challenging. The introduction of digital single-operator cholangioscopy (DSOC) that allows direct visual inspection of the lesion and targeted biopsy sampling significantly improved the diagnostic yield in patients with indeterminate BSs. However, the diagnostic efficiency of DSOC remains suboptimal. Convolutional neural networks (CNNs) have shown great potential for the interpretation of medical images. We aimed to develop a CNN-based system for automatic detection of malignant BSs in DSOC images. METHODS: We developed, trained, and validated a CNN-based on DSOC images. Each frame was labeled as a normal/benign finding or as a malignant lesion if histopathologic evidence of biliary malignancy was available. The entire dataset was split for 5-fold cross-validation. In addition, the image dataset was split for constitution of training and validation datasets. The performance of the CNN was measured by calculating the area under the receiving operating characteristic curve (AUC), sensitivity, specificity, and positive and negative predictive values. RESULTS: A total of 11,855 images from 85 patients were included (9695 malignant strictures and 2160 benign findings). The model had an overall accuracy of 94.9%, sensitivity of 94.7%, specificity of 92.1%, and AUC of .988 in cross-validation analysis. The image processing speed of the CNN was 7 ms per frame. CONCLUSIONS: The developed deep learning algorithm accurately detected and differentiated malignant strictures from benign biliary conditions. The introduction of artificial intelligence algorithms to DSOC systems may significantly increase its diagnostic yield for malignant strictures.


Assuntos
Inteligência Artificial , Neoplasias do Sistema Biliar , Neoplasias do Sistema Biliar/complicações , Neoplasias do Sistema Biliar/diagnóstico , Constrição Patológica/diagnóstico , Constrição Patológica/etiologia , Endoscopia do Sistema Digestório/métodos , Humanos , Projetos Piloto
3.
Am J Obstet Gynecol ; 227(2): 267.e1-267.e20, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35101408

RESUMO

BACKGROUND: During the second stage of labor, the maternal pelvic floor muscles undergo repetitive stretch loading as uterine contractions and strenuous maternal pushes combined to expel the fetus, and it is not uncommon that these muscles sustain a partial or complete rupture. It has recently been demonstrated that soft tissues, including the anterior cruciate ligament and connective tissue in sheep pelvic floor muscle, can accumulate damage under repetitive physiological (submaximal) loads. It is well known to material scientists that this damage accumulation can not only decrease tissue resistance to stretch but also result in a partial or complete structural failure. Thus, we wondered whether certain maternal pushing patterns (in terms of frequency and duration of each push) could increase the risk of excessive damage accumulation in the pelvic floor tissue, thereby inadvertently contributing to the development of pelvic floor muscle injury. OBJECTIVE: This study aimed to determine which labor management practices (spontaneous vs directed pushing) are less prone to accumulate damage in the pelvic floor muscles during the second stage of labor and find the optimum approach in terms of minimizing the risk of pelvic floor muscle injury. STUDY DESIGN: We developed a biomechanical model for the expulsive phase of the second stage of labor that includes the ability to measure the damage accumulation because of repetitive physiological submaximal loads. We performed 4 simulations of the second stage of labor, reflecting a directed pushing technique and 3 alternatives for spontaneous pushing. RESULTS: The finite element model predicted that the origin of the pubovisceral muscle accumulates the most damage and so it is the most likely place for a tear to develop. This result was independent of the pushing pattern. Performing 3 maternal pushes per contraction, with each push lasting 5 seconds, caused less damage and seemed the best approach. The directed pushing technique (3 pushes per contraction, with each push lasting 10 seconds) did not reduce the duration of the second stage of labor and caused higher damage accumulation. CONCLUSION: The frequency and duration of the maternal pushes influenced the damage accumulation in the passive tissues of the pelvic floor muscles, indicating that it can influence the prevalence of pelvic floor muscle injuries. Our results suggested that the maternal pushes should not last longer than 5 seconds and that the duration of active pushing is a better measurement than the total duration of the second stage of labor. Hopefully, this research will help to shed new light on the best practices needed to improve the experience of labor for women.


Assuntos
Parto Obstétrico , Segunda Fase do Trabalho de Parto , Animais , Parto Obstétrico/métodos , Fadiga , Feminino , Humanos , Segunda Fase do Trabalho de Parto/fisiologia , Diafragma da Pelve/fisiologia , Gravidez , Ovinos , Contração Uterina/fisiologia
4.
J Nanobiotechnology ; 19(1): 52, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33608025

RESUMO

BACKGROUND: Sepsis is an emergency medical condition that can lead to death and it is defined as a life-threatening organ dysfunction caused by immune dysregulation in response to an infection. It is considered the main killer in intensive care units. Sepsis associated-encephalopathy (SAE) is mostly caused by a sepsis-induced systemic inflammatory response. Studies report SAE in 14-63% of septic patients. Main SAE symptoms are not specific and usually include acute impairment of consciousness, delirium and/or coma, along with electroencephalogram (EEG) changes. For those who recover from sepsis and SAE, impaired cognitive function, mobility and quality of life are often observed months to years after hospital discharge, and there is no treatment available today to prevent that. Inflammation and oxidative stress are key players for the SAE pathophysiology. Gold nanoparticles have been demonstrated to own important anti-inflammatory properties. It was also reported 20 nm citrate-covered gold nanoparticles (cit-AuNP) reduce oxidative stress. In this context, we tested whether 20 nm cit-AuNP could alleviate the acute changes caused by sepsis in brain of mice, with focus on inflammation. Sepsis was induced in female C57BL/6 mice by cecal ligation and puncture (CLP), 20 nm cit-AuNP or saline were intravenously (IV) injected 2 h after induction of sepsis and experiments performed 6 h after induction. Intravital microscopy was used for leukocyte and platelet adhesion study in brain, blood brain barrier (BBB) permeability carried out by Evans blue assay, cytokines measured by ELISA and real time PCR, cell adhesion molecules (CAMs) by flow cytometry and immunohistochemistry, and transcription factors, by western blotting. RESULTS: 20 nm cit-AuNP treatment reduced leukocyte and platelet adhesion to cerebral blood vessels, prevented BBB failure, reduced TNF- concentration in brain, and ICAM-1 expression both in circulating polymorphonuclear (PMN) leukocytes and cerebral blood vessels of mice with sepsis. Furthermore, 20 nm cit-AuNP did not interfere with the antibiotic effect on the survival rate of mice with sepsis. CONCLUSIONS: Cit-AuNP showed important anti-inflammatory properties in the brain of mice with sepsis, being a potential candidate to be used as adjuvant drug along with antibiotics in the treatment of sepsis to avoid SAE.


Assuntos
Ceco/metabolismo , Ouro/farmacologia , Inflamação/tratamento farmacológico , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Microvasos/metabolismo , Sepse/tratamento farmacológico , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Encefalopatias , Adesão Celular , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Inflamação/patologia , Leucócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microvasos/patologia , Neutrófilos/metabolismo , Qualidade de Vida , Sepse/metabolismo , Sepse/patologia , Encefalopatia Associada a Sepse/metabolismo
8.
J Sci Food Agric ; 94(3): 529-36, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23801071

RESUMO

BACKGROUND: Plants have developed an efficient system of recognition that induces a complex network of signalling molecules such as salicylic acid (SA), jasmonic acid (JA) and abscisic acid (ABA) in case of a pathogenic infection. The use of specific and sensitive methods is mandatory for the analysis of compounds in these complex samples. RESULTS: In this study a liquid chromatography/electrospray ionisation tandem mass spectrometry method was developed and validated for the simultaneous quantification of SA, JA and ABA in Coffea arabica (L.) leaves in order to understand the role of these phytohormones in the signalling network involved in the coffee defence response against Hemileia vastatrix. The results showed that the method was specific, linear (r ≥ 0.99) in the range 0.125-1.00 µg mL⁻¹ for JA and ABA and 0.125-5.00 µg mL⁻¹ for SA, and precise (relative standard deviation ≤11%), and the limit of detection (0.010 µg g⁻¹ fresh weight) was adequate for quantifying these phytohormones in this type of matrix. CONCLUSION: In comparison with healthy leaves, those infected with H. vastatrix (resistance reaction) displayed an increase in SA level 24 h after inoculation, suggesting the involvement of an SA-dependent pathway in coffee resistance.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Coffea/química , Resistência à Doença , Doenças das Plantas/microbiologia , Reguladores de Crescimento de Plantas/análise , Folhas de Planta/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Ácido Abscísico/análise , Coffea/microbiologia , Ciclopentanos/análise , Fungos , Oxilipinas/análise , Folhas de Planta/microbiologia , Reprodutibilidade dos Testes , Ácido Salicílico/análise , Transdução de Sinais , Espectrometria de Massas em Tandem/métodos
9.
Therap Adv Gastroenterol ; 17: 17562848241251569, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38812708

RESUMO

Background: Capsule endoscopy (CE) is a valuable tool for assessing inflammation in patients with Crohn's disease (CD). The current standard for evaluating inflammation are validated scores (and clinical laboratory values) like Lewis score (LS), Capsule Endoscopy Crohn's Disease Activity Index (CECDAI), and ELIAKIM. Recent advances in artificial intelligence (AI) have made it possible to automatically select the most relevant frames in CE. Objectives: In this proof-of-concept study, our objective was to develop an automated scoring system using CE images to objectively grade inflammation. Design: Pan-enteric CE videos (PillCam Crohn's) performed in CD patients between 09/2020 and 01/2023 were retrospectively reviewed and LS, CECDAI, and ELIAKIM scores were calculated. Methods: We developed a convolutional neural network-based automated score consisting of the percentage of positive frames selected by the algorithm (for small bowel and colon separately). We correlated clinical data and the validated scores with the artificial intelligence-generated score (AIS). Results: A total of 61 patients were included. The median LS was 225 (0-6006), CECDAI was 6 (0-33), ELIAKIM was 4 (0-38), and SB_AIS was 0.5659 (0-29.45). We found a strong correlation between SB_AIS and LS, CECDAI, and ELIAKIM scores (Spearman's r = 0.751, r = 0.707, r = 0.655, p = 0.001). We found a strong correlation between LS and ELIAKIM (r = 0.768, p = 0.001) and a very strong correlation between CECDAI and LS (r = 0.854, p = 0.001) and CECDAI and ELIAKIM scores (r = 0.827, p = 0.001). Conclusion: Our study showed that the AI-generated score had a strong correlation with validated scores indicating that it could serve as an objective and efficient method for evaluating inflammation in CD patients. As a preliminary study, our findings provide a promising basis for future refining of a CE score that may accurately correlate with prognostic factors and aid in the management and treatment of CD patients.


Artificial intelligence in Crohn's disease: the development of an automated score for disease activity evaluation This study introduces an innovative AI-based approach to evaluate Crohn's Disease. The AI system automatically analyzes images from capsule endoscopy, focusing on finding ulcers and erosions to measure disease activity. The research reveals a robust correlation between the AI-generated score assessing inflammation in the small bowel and traditional clinical scores. This suggests that the AI solution could be a quicker and more consistent way to evaluate Crohn's Disease, speeding up the evaluation process and reducing manual scoring variability. While promising, the study acknowledges limitations and emphasizes the need for further validation with larger groups of patients. Overall, it represents a crucial step toward integrating AI into gastroenterology, offering a glimpse into a future of more objective and personalized Crohn's Disease evaluation.

10.
Cancers (Basel) ; 16(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38201634

RESUMO

Device-assisted enteroscopy (DAE) is capable of evaluating the entire gastrointestinal tract, identifying multiple lesions. Nevertheless, DAE's diagnostic yield is suboptimal. Convolutional neural networks (CNN) are multi-layer architecture artificial intelligence models suitable for image analysis, but there is a lack of studies about their application in DAE. Our group aimed to develop a multidevice CNN for panendoscopic detection of clinically relevant lesions during DAE. In total, 338 exams performed in two specialized centers were retrospectively evaluated, with 152 single-balloon enteroscopies (Fujifilm®, Porto, Portugal), 172 double-balloon enteroscopies (Olympus®, Porto, Portugal) and 14 motorized spiral enteroscopies (Olympus®, Porto, Portugal); then, 40,655 images were divided in a training dataset (90% of the images, n = 36,599) and testing dataset (10% of the images, n = 4066) used to evaluate the model. The CNN's output was compared to an expert consensus classification. The model was evaluated by its sensitivity, specificity, positive (PPV) and negative predictive values (NPV), accuracy and area under the precision recall curve (AUC-PR). The CNN had an 88.9% sensitivity, 98.9% specificity, 95.8% PPV, 97.1% NPV, 96.8% accuracy and an AUC-PR of 0.97. Our group developed the first multidevice CNN for panendoscopic detection of clinically relevant lesions during DAE. The development of accurate deep learning models is of utmost importance for increasing the diagnostic yield of DAE-based panendoscopy.

11.
Cancers (Basel) ; 15(2)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36672309

RESUMO

Bladder cancer (BlCa), specifically urothelial carcinomas, is a heterogeneous disease that derives from the urothelial lining. Two main classes of BlCa are acknowledged: the non-muscle invasive BlCa and the muscle-invasive BlCa; the latter constituting an aggressive disease which invades locally and metastasizes systemically. Distinguishing the specific microenvironment that cancer cells experience between mucosa and muscularis propria layers can help elucidate how these cells acquire invasive capacities. In this work, we propose to measure the micromechanical properties of both mucosa and muscularis propria layers of the bladder wall of BlCa patients, using atomic force microscopy (AFM). To do that, two cross-sections of both the macroscopically normal urinary bladder wall and the bladder wall adjacent to the tumor were collected and immediately frozen, prior to AFM samples analysis. The respective "twin" formalin-fixed paraffin-embedded tissue fragments were processed and later evaluated for histopathological examination. H&E staining suggested that tumors promoted the development of muscle-like structures in the mucosa surrounding the neoplastic region. The average Young's modulus (cell stiffness) in tumor-adjacent specimens was significantly higher in the muscularis propria than in the mucosa. Similarly, the tumor-free specimens had significantly higher Young's moduli in the muscularis propria than in the urothelium. Young's moduli were higher in all layers of tumor-adjacent tissues when compared with tumor-free samples. Here we provide insights into the stiffness of the bladder wall layers, and we show that the presence of tumor in the surrounding mucosa leads to an alteration of its smooth muscle content. The quantitative assessment of stiffness range here presented provides essential data for future research on BlCa and for understanding how the biomechanical stimuli can modulate cancer cells' capacity to invade through the different bladder layers.

12.
Eur J Emerg Med ; 30(2): 85-90, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36735452

RESUMO

BACKGROUND AND IMPORTANCE: Acute heart failure (AHF) is one of the main causes of unplanned hospitalization in patients >65 years of age and is associated with adverse outcomes in this population. Observational studies suggest that intravenous diuretic therapy given in the first hour of presentation for AHF was associated with favorable outcomes. OBJECTIVES: To study the short-term prognostic associations of the timing of intravenous diuretic therapy in patients admitted to the emergency department (ED) for acute AHF. DESIGN, SETTINGS AND PARTICIPANTS: Patients treated in the ED with intravenous diuretics were selected from the Estratificação de Doentes com InsuFIciência Cardíaca Aguda (EDIFICA) registry, a prospective study including AHF hospitalized patients. Early and non-early furosemide treatment groups were considered using the 1-h cutoff: door-to-furosemide ≤1 h and >1 h. OUTCOMES MEASURE AND ANALYSIS: Primary outcomes were a composite of heart failure re-hospitalizations or cardiovascular death at 30- and 90-days. MAIN RESULTS: Four-hundred ninety-three patients were included in the analysis. The median (interquartile range) door-to-furosemide time was 85 (41-220) min, and 210 (43%) patients had diuretics in the first hour. Patients in the ≤1 h group had higher evaluation priority according to the Manchester Triage System, presented more often with acute pulmonary edema, warm-wet clinical profile, higher blood pressure, and signs of left-side heart failure, while >1 h group had higher Get With the Guidelines-heart failure risk score, more frequent signs of right-side heart failure, higher circulating B-type natriuretic peptides and lower albumin. Door-to-furosemide ≤ 1 h was independently associated with lower 30-day heart failure hospitalizations and composite of heart failure hospitalizations or cardiovascular death (adjusted analysis Heart Failure Hospitalizations: odds ratios (OR) 3.65; 95% confidence interval (CI), 1.22-10.9; P = 0.020; heart failure hospitalizations or cardiovascular death: OR 3.15; 95% CI, 1.49-6.64; P < 0.001). These independent associations lost significance at 90 days. CONCLUSION: Door-to-furosemide ≤1 h was associated with a lower short-term risk of heart failure hospitalizations or cardiovascular death in AHF patients. Our findings add to the existing evidence that early identification and intravenous diuretic therapy of AHF patients may improve outcomes.


Assuntos
Furosemida , Insuficiência Cardíaca , Humanos , Doença Aguda , Diuréticos , Insuficiência Cardíaca/diagnóstico , Estudos Prospectivos
13.
Cancers (Basel) ; 15(19)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37835521

RESUMO

Digital single-operator cholangioscopy (D-SOC) has enhanced the ability to diagnose indeterminate biliary strictures (BSs). Pilot studies using artificial intelligence (AI) models in D-SOC demonstrated promising results. Our group aimed to develop a convolutional neural network (CNN) for the identification and morphological characterization of malignant BSs in D-SOC. A total of 84,994 images from 129 D-SOC exams in two centers (Portugal and Spain) were used for developing the CNN. Each image was categorized as either a normal/benign finding or as malignant lesion (the latter dependent on histopathological results). Additionally, the CNN was evaluated for the detection of morphologic features, including tumor vessels and papillary projections. The complete dataset was divided into training and validation datasets. The model was evaluated through its sensitivity, specificity, positive and negative predictive values, accuracy and area under the receiver-operating characteristic and precision-recall curves (AUROC and AUPRC, respectively). The model achieved a 82.9% overall accuracy, 83.5% sensitivity and 82.4% specificity, with an AUROC and AUPRC of 0.92 and 0.93, respectively. The developed CNN successfully distinguished benign findings from malignant BSs. The development and application of AI tools to D-SOC has the potential to significantly augment the diagnostic yield of this exam for identifying malignant strictures.

14.
Diagnostics (Basel) ; 12(6)2022 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-35741255

RESUMO

BACKGROUND: Colon capsule endoscopy (CCE) is an alternative for patients unwilling or with contraindications for conventional colonoscopy. Colorectal cancer screening may benefit greatly from widespread acceptance of a non-invasive tool such as CCE. However, reviewing CCE exams is a time-consuming process, with risk of overlooking important lesions. We aimed to develop an artificial intelligence (AI) algorithm using a convolutional neural network (CNN) architecture for automatic detection of colonic protruding lesions in CCE images. An anonymized database of CCE images collected from a total of 124 patients was used. This database included images of patients with colonic protruding lesions or patients with normal colonic mucosa or with other pathologic findings. A total of 5715 images were extracted for CNN development. Two image datasets were created and used for training and validation of the CNN. The AUROC for detection of protruding lesions was 0.99. The sensitivity, specificity, PPV and NPV were 90.0%, 99.1%, 98.6% and 93.2%, respectively. The overall accuracy of the network was 95.3%. The developed deep learning algorithm accurately detected protruding lesions in CCE images. The introduction of AI technology to CCE may increase its diagnostic accuracy and acceptance for screening of colorectal neoplasia.

15.
Int J Numer Method Biomed Eng ; 38(5): e3588, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35266291

RESUMO

Regular intestinal motility is essential to guarantee complete digestive function. The coordinative action and integrity of the smooth muscle layers in the small intestine's wall are critical for mixing and propelling the luminal content. However, some patients present gastrointestinal limitations which may negatively impact the normal motility of the intestine. These patients have altered mechanical and muscle properties that likely impact chyme propulsion and may pose a daily scenario for long-term complications. To better understand how mechanics affect chyme propulsion, the propulsive capability of the small intestine was examined during a peristaltic wave along the distal direction of the tract. It was assumed that such a wave works as an activation signal, inducing peristaltic contractions in a transversely isotropic hyperelastic model. In this work, the effect on the propulsion mechanics, from an impairment on the muscle contractile ability, typical from patients with systemic sclerosis, and the presence of sores resultant from ulcers was evaluated. The passive properties of the constitutive model were obtained from uniaxial tensile tests from a porcine small intestine, along with both longitudinal and circumferential directions. Our experiments show decreased stiffness in the circumferential direction. Our simulations show decreased propulsion forces in patients in systemic sclerosis and ulcer patients. As these patients may likely need medical intervention, establishing action concerning the impaired propulsion can help to ease the evaluation and treatment of future complications.


Assuntos
Peristaltismo , Escleroderma Sistêmico , Animais , Motilidade Gastrointestinal/fisiologia , Humanos , Intestino Delgado/fisiologia , Contração Muscular/fisiologia , Peristaltismo/fisiologia , Suínos
16.
Endosc Int Open ; 10(2): E171-E177, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35186665

RESUMO

Background and study aims Colon capsule endoscopy (CCE) is a minimally invasive alternative to conventional colonoscopy. However, CCE produces long videos, making its analysis time-consuming and prone to errors. Convolutional neural networks (CNN) are artificial intelligence (AI) algorithms with high performance levels in image analysis. We aimed to develop a deep learning model for automatic identification and differentiation of significant colonic mucosal lesions and blood in CCE images. Patients and methods A retrospective multicenter study including 124 CCE examinations was conducted for development of a CNN model, using a database of CCE images including anonymized images of patients with normal colon mucosa, several mucosal lesions (erosions, ulcers, vascular lesions and protruding lesions) and luminal blood. For CNN development, 9005 images (3,075 normal mucosa, 3,115 blood and 2,815 mucosal lesions) were ultimately extracted. Two image datasets were created and used for CNN training and validation. Results The mean (standard deviation) sensitivity and specificity of the CNN were 96.3 % (3.9 %) and 98.2 % (1.8 %) Mucosal lesions were detected with a sensitivity of 92.0 % and a specificity of 98.5 %. Blood was detected with a sensitivity and specificity of 97.2 % and 99.9 %, respectively. The algorithm was 99.2 % sensitive and 99.6 % specific in distinguishing blood from mucosal lesions. The CNN processed 65 frames per second. Conclusions This is the first CNN-based algorithm to accurately detect and distinguish colonic mucosal lesions and luminal blood in CCE images. AI may improve diagnostic and time efficiency of CCE exams, thus facilitating CCE adoption to routine clinical practice.

17.
Endosc Int Open ; 10(3): E262-E268, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35295246

RESUMO

Background and study aims Indeterminate biliary strictures pose a significative clinical challenge. Dilated, irregular, and tortuous vessels, often described as tumor vessels, are frequently reported in biliary strictures with high malignancy potential during digital single-operator cholangioscopy (D-SOC). In recent years, the development of artificial intelligence (AI) algorithms for application to endoscopic practice has been intensely studied. We aimed to develop an AI algorithm for automatic detection of tumor vessels (TVs) in D-SOC images. Patients and methods A convolutional neural network (CNN) was developed. A total of 6475 images from 85 patients who underwent D-SOC (Spyglass, Boston Scientific, Marlborough, Massachusetts, United States) were included. Each frame was evaluated for the presence of TVs. The performance of the CNN was measured by calculating the area under the curve (AUC), sensitivity, specificity, positive and negative predictive values. Results The sensitivity, specificity, positive predictive value, and negative predictive value were 99.3 %, 99.4 %, 99.6% and 98.7 %, respectively. The AUC was 1.00. Conclusions Our CNN was able to detect TVs with high accuracy. Development of AI algorithms may enhance the detection of macroscopic characteristics associated with high probability of biliary malignancy, thus optimizing the diagnostic workup of patients with indeterminate biliary strictures.

18.
Int J Rheum Dis ; 25(6): 669-677, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35429115

RESUMO

OBJECTIVES: Differences in proteomic profiles between men and women may provide insights into the biological pathways that contribute to known sex differences in rheumatoid arthritis (RA). Studies focusing on sex differences in circulating proteins in RA patients are scarce. Our objective was to investigate the sex differences in circulating proteins of RA patients. METHODS: Cohort study enrolling 399 RA patients. Ninety-four circulating protein-biomarkers (92CVDIIOlink®  + troponin-T + C-reactive protein) were measured. Clinical, demographic, and echocardiographic characteristics were compared between men and women. Sex differences in biomarker expression were assessed using regression modeling. RESULTS: In all, 306 (76.7%) patients were women. Compared with men, women had less visceral fat, smoked less, had diabetes and chronic obstructive pulmonary disease less frequently, and expressed more fatigue, anxiety, and depression. The association with cardiovascular outcomes did not differ between sexes. After adjusting for potential confounders, women expressed higher levels of circulating proteins related to adipokine signaling and vascular function (eg, leptin and vascular endothelial growth factor), whereas men expressed higher levels of circulating proteins related to extracellular matrix organization and inflammation (eg, matrix metalloproteinase-2 and C-reactive protein). These results were not found in patients without RA. CONCLUSION: Sex differences in circulating proteins reflect distinct pathways implicated in the pathogenesis of RA, including inflammation, adiposity, angiogenesis, and extracellular matrix organization. These findings may help further investigations into factors underlying sex-based differences and allow future studies focused on sex-specific personalized treatment approaches in RA. CLINICALTRIALS: gov ID: NCT03960515.


Assuntos
Artrite Reumatoide , Proteína C-Reativa , Artrite Reumatoide/complicações , Biomarcadores , Proteína C-Reativa/análise , Estudos de Coortes , Feminino , Humanos , Inflamação/complicações , Masculino , Metaloproteinase 2 da Matriz , Proteômica , Caracteres Sexuais , Fator A de Crescimento do Endotélio Vascular
19.
GE Port J Gastroenterol ; 29(5): 331-338, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36159196

RESUMO

Introduction: Capsule endoscopy has revolutionized the management of patients with obscure gastrointestinal bleeding. Nevertheless, reading capsule endoscopy images is time-consuming and prone to overlooking significant lesions, thus limiting its diagnostic yield. We aimed to create a deep learning algorithm for automatic detection of blood and hematic residues in the enteric lumen in capsule endoscopy exams. Methods: A convolutional neural network was developed based on a total pool of 22,095 capsule endoscopy images (13,510 images containing luminal blood and 8,585 of normal mucosa or other findings). A training dataset comprising 80% of the total pool of images was defined. The performance of the network was compared to a consensus classification provided by 2 specialists in capsule endoscopy. Subsequently, we evaluated the performance of the network using an independent validation dataset (20% of total image pool), calculating its sensitivity, specificity, accuracy, and precision. Results: Our convolutional neural network detected blood and hematic residues in the small bowel lumen with an accuracy and precision of 98.5 and 98.7%, respectively. The sensitivity and specificity were 98.6 and 98.9%, respectively. The analysis of the testing dataset was completed in 24 s (approximately 184 frames/s). Discussion/Conclusion: We have developed an artificial intelligence tool capable of effectively detecting luminal blood. The development of these tools may enhance the diagnostic accuracy of capsule endoscopy when evaluating patients presenting with obscure small bowel bleeding.


Introdução: A endoscopia por cápsula revolucionou a abordagem a doentes com hemorragia digestiva obscura. No entanto, a leitura de imagens de endoscopia por cápsula é morosa, havendo suscetibilidade para a perda de lesões significativas, limitando desta forma a sua eficácia diagnóstica. Este estudo visou a criação de um algoritmo de deep learning para deteção automática de sangue e resíduos hemáticos no lúmen entérico usando imagens de endoscopia por cápsula. Métodos: Foi desenvolvida uma rede neural convolucional com base num conjunto de 22,095 imagens de endoscopia de cápsula (13,510 imagens contendo sangue e 8,585 mucosa normal ou outros achados). Foi construído um grupo de imagens para treino, compreendendo 80% do total de imagens. O desempenho da rede foi comparado com a classificação consenso de dois especialistas em endoscopia por cápsula. Posteriormente, o desempenho da rede foi avaliado usando os restantes 20% de imagens. Foi calculada a sua sensibilidade, especificidade, exatidão e precisão. Resultados: O algoritmo detetou sangue e resíduos hemáticos no lúmen do intestino delgado com uma exatidão e precisão de 98.5% e 98.7%, respetivamente. A sensibilidade e especificidade foram 98.6% e 98.9%, respetivamente. A análise do conjunto de usado para teste da rede foi concluída em 24 segundos (aproximadamente 184 frames/s). Discussão/Conclusão: Foi desenvolvida uma ferramenta de inteligência artificial capaz de detetar efetivamente o sangue luminal. O desenvolvimento dessas ferramentas pode aumentar a precisão do diagnóstico da endoscopia por cápsula ao avaliar pacientes que apresentam sangramento obscuro do intestino delgado.

20.
J Tissue Eng Regen Med ; 15(11): 883-899, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34339588

RESUMO

The mechanical environment of living cells is as critical as chemical signaling. Mechanical stimuli play a pivotal role in organogenesis and tissue homeostasis. Unbalances in mechanotransduction pathways often lead to diseases, such as cancer, cystic fibrosis, and neurodevelopmental disorders. Despite its inherent relevance, there is a lack of proper mechanoresponsive in vitro study systems. In this context, there is an urge to engineer innovative, robust, dynamic, and reliable organotypic technologies to better connect cellular processes to organ-level function and multi-tissue cross-talk. Mechanically active organoid-on-chip has the potential to surpass this challenge. These systems converge microfabrication, microfluidics, biophysics, and tissue engineering fields to emulate key features of living organisms, hence, reducing costs, time, and animal testing. In this review, we intended to present cutting-edge organ-on-chip platforms that integrate biomechanical stimuli as well as novel multicellular culture, such as organoids. We focused on its application in two main fields: precision medicine and drug development. Moreover, we also discussed the state of the art for the development of an engineered model to assess patient-derived tumor organoid metastatic potential. Finally, we highlighted the current drawbacks and emerging opportunities to match the industry needs. We envision the use of mechanoresponsive organotypic-on-chip microdevices as an indispensable tool for precision medicine, drug development, disease modeling, tissue engineering, and developmental biology.


Assuntos
Biofísica , Dispositivos Lab-On-A-Chip , Organoides/fisiologia , Engenharia Tecidual , Animais , Fenômenos Biomecânicos , Encéfalo/fisiologia , Humanos , Microfluídica
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