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1.
Ann Surg ; 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39176476

RESUMO

OBJECTIVE: To evaluate the feasibility of developing a computer vision algorithm that uses preoperative computed tomography (CT) scans to predict superior mesenteric artery (SMA) margin status in patients undergoing Whipple for pancreatic ductal adenocarcinoma (PDAC), and to compare algorithm performance to that of expert abdominal radiologists and surgical oncologists. SUMMARY BACKGROUND DATA: Complete surgical resection is the only chance to achieve a cure for PDAC; however, current modalities to predict vascular invasion have limited accuracy. METHODS: Adult patients with PDAC who underwent Whipple and had preoperative contrast-enhanced CT scans were included (2010-2022). The SMA was manually annotated on the CT scans, and we trained a U-Net algorithm for SMA segmentation and a ResNet50 algorithm for predicting SMA margin status. Radiologists and surgeons reviewed the scans in a blinded fashion. SMA margin status per pathology reports was the reference. RESULTS: Two hundred patients were included. Forty patients (20%) had a positive SMA margin. For the segmentation task, the U-Net model achieved a Dice Similarity Coefficient of 0.90. For the classification task, all readers demonstrated limited sensitivity, although the algorithm had the highest sensitivity at 0.43 (versus 0.23 and 0.36 for the radiologists and surgeons, respectively). Specificity was universally excellent, with the radiologist and algorithm demonstrating the highest specificity at 0.94. Finally, the accuracy of the algorithm was 0.85 versus 0.80 and 0.76 for the radiologists and surgeons, respectively. CONCLUSIONS: We demonstrated the feasibility of developing a computer vision algorithm to predict SMA margin status using preoperative CT scans, highlighting its potential to augment the prediction of vascular involvement.

2.
J Am Chem Soc ; 136(31): 10846-9, 2014 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-25036460

RESUMO

O2 bubbling into a THF solution of Fe(II)(BDPP) (1) at -80 °C generates a reversible bright yellow adduct 2. Characterization by resonance Raman and Mössbauer spectroscopy provides complementary insights into the nature of 2. The former shows a resonance-enhanced vibration at 1125 cm(-1), which can be assigned to the ν(O-O) of a bound superoxide, while the latter reveals the presence of a high-spin iron(III) center that is exchange-coupled to the superoxo ligand, like the Fe(III)-O2(-) pair found for the O2 adduct of 4-nitrocatechol-bound homoprotocatechuate 2,3-dioxygenase. Lastly, 2 oxidizes dihydroanthracene to anthracene, supporting the notion that Fe(III)-O2(-) species can carry out H atom abstraction from a C-H bond to initiate the 4-electron oxidation of substrates proposed for some nonheme iron enzymes.


Assuntos
Ferro/química , Imãs/química , Compostos Organometálicos/química , Oxigênio/química , Modelos Moleculares , Conformação Molecular
3.
Hepatol Commun ; 8(7)2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38896084

RESUMO

BACKGROUND: Serum AFP-L3%, AFP, and DCP are useful biomarkers for HCC detection, but their utility in assessing treatment response remains unknown. We aim to evaluate the accuracy of a biomarker model in the detection of posttreatment viable tumors. METHODS: For model derivation, recipients with HCC undergoing liver transplant from 2018 to 2022 who had biomarkers collected within 3 months before transplant were included. We developed a generalized linear model for detecting posttreatment viable tumors with the 3 biomarkers as covariates, which we termed the "LAD Score." An independent cohort of 117 patients with HCC was used for external validation. RESULTS: Among 205 recipients of transplant, 70.2% had evidence of viable tumor on explant. The median LAD score was higher among patients with viable versus nonviable tumors (1.06 vs. 0.465, p < 0.001). The LAD score had a sensitivity of 55.6% and a specificity of 85.1% at the cutoff of 0.927, which was more accurate than imaging for detecting posttreatment viable tumors (AUROC 0.736 vs. 0.643, respectively; p = 0.045). The superior performance of the LAD score over imaging is primarily driven by its greater accuracy in detecting tumors <2 cm in diameter (AUROC of the LAD score 0.721 vs. imaging 0.595, p = 0.02). In the validation data set, the LAD score had an AUROC of 0.832 (95% CI: 0.753, 0.911) with a sensitivity of 72.5% and a specificity of 89.4% at the cutoff of 0.927. CONCLUSIONS: Our findings suggest the utility of LAD score in treatment response assessment after locoregional therapy for HCC, particularly in detecting small tumors. A larger prospective study is in progress to validate its accuracy and evaluate its performance in recurrence monitoring.


Assuntos
Biomarcadores Tumorais , Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , alfa-Fetoproteínas , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/patologia , Feminino , Masculino , Pessoa de Meia-Idade , Biomarcadores Tumorais/sangue , alfa-Fetoproteínas/análise , Idoso , Resultado do Tratamento , Sensibilidade e Especificidade , Estudos Retrospectivos
4.
Artigo em Inglês | MEDLINE | ID: mdl-34065262

RESUMO

The objective of this study was to determine how coronary computed tomography angiography (CCTA) can be employed to detect coronary artery disease in hospital employees, enabling early treatment and minimizing damage. All employees of our hospital were assessed using the Framingham Risk Score. Those with a 10-year risk of myocardial infarction or death of >10% were offered CCTA; the Coronary Artery Disease Reporting and Data System (CAD-RADS) score was the outcome. A total of 3923 hospital employees were included, and the number who had received CCTA was 309. Among these 309, 31 (10.0%) had a CAD-RADS score of 3-5, with 10 of the 31 (32.3%) requiring further cardiac catheterization; 161 (52.1%) had a score of 1-2; and 117 (37.9%) had a score of 0. In the multivariate logistic regression, only age of ≥ 55 years (p < 0.05), hypertension (p < 0.05), and hyperlipidemia (p < 0.05) were discovered to be significant risk factors for a CAD-RADS score of 3-5. Thus, regular and adequate control of chronic diseases is critical for patients, and more studies are required to be confirmed if there are more significant risk factors.


Assuntos
Doenças Cardiovasculares , Doença da Artéria Coronariana , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/epidemiologia , Fatores de Risco de Doenças Cardíacas , Hospitais , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de Risco
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