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1.
Biometals ; 26(2): 271-83, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23361163

RESUMO

The Rhizobia are a group of free-living soil bacteria known for their ability to symbiotically infect the roots of specific host plants as well as to produce siderophores in order to compete with other microorganisms for the limited availability of iron in the rhizosphere. In this study, Rhizobium leguminosarum ATCC 14479, which preferentially infects the red clover Trifolium pratense, was found to produce the trihydroxamate siderophore vicibactin (C33H55N6O15) under iron restricted conditions. In addition, two other iron-binding, siderophore-like compounds: C20H36N4O10, C31H55N6O15, were isolated and purified from the culture media. Due to the structural similarity of the latter compounds to vicibactin based on electrospray-mass spectrometry and nuclear magnetic resonance data, these heretofore unreported molecules are thought to be either modified or degraded products of vicibactin. Although vicibactin has previously been found to be commonly produced by other rhizobial strains, this is the first time it has been chemically characterized from a clover infecting strain of R. leguminosarum.


Assuntos
Peptídeos Cíclicos/biossíntese , Rhizobium leguminosarum/metabolismo , Simbiose , Trifolium/metabolismo , Ferro/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Sideróforos/biossíntese , Microbiologia do Solo
3.
J Biomed Opt ; 27(4)2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35484692

RESUMO

SIGNIFICANCE: Automatic, fast, and accurate identification of cancer on histologic slides has many applications in oncologic pathology. AIM: The purpose of this study is to investigate hyperspectral imaging (HSI) for automatic detection of head and neck cancer nuclei in histologic slides, as well as cancer region identification based on nuclei detection. APPROACH: A customized hyperspectral microscopic imaging system was developed and used to scan histologic slides from 20 patients with squamous cell carcinoma (SCC). Hyperspectral images and red, green, and blue (RGB) images of the histologic slides with the same field of view were obtained and registered. A principal component analysis-based nuclei segmentation method was developed to extract nuclei patches from the hyperspectral images and the coregistered RGB images. Spectra-based support vector machine and patch-based convolutional neural networks (CNNs) were implemented for nuclei classification. The CNNs were trained with RGB patches (RGB-CNN) and hyperspectral patches (HSI-CNN) of the segmented nuclei and the utility of the extra spectral information provided by HSI was evaluated. Furthermore, cancer region identification was implemented by image-wise classification based on the percentage of cancerous nuclei detected in each image. RESULTS: RGB-CNN, which mainly used the spatial information of nuclei, resulted in a 0.81 validation accuracy and 0.74 testing accuracy. HSI-CNN, which utilized the spatial and spectral features of the nuclei, showed significant improvement in classification performance and achieved 0.89 validation accuracy as well as 0.82 testing accuracy. Furthermore, the image-wise cancer region identification based on nuclei detection could generally improve the cancer detection rate. CONCLUSIONS: We demonstrated that the morphological and spectral information contribute to SCC nuclei differentiation and that the spectral information within hyperspectral images could improve classification performance.


Assuntos
Neoplasias de Cabeça e Pescoço , Imageamento Hiperespectral , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Humanos , Redes Neurais de Computação , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagem , Máquina de Vetores de Suporte
4.
Artigo em Inglês | MEDLINE | ID: mdl-36798628

RESUMO

Hyperspectral imaging (HSI) and radiomics have the potential to improve the accuracy of tumor malignancy prediction and assessment. In this work, we extracted radiomic features of fresh surgical papillary thyroid carcinoma (PTC) specimen that were imaged with HSI. A total of 107 unique radiomic features were extracted. This study includes 72 ex-vivo tissue specimens from 44 patients with pathology-confirmed PTC. With the dilated hyperspectral images, the shape feature of least axis length was able to predict the tumor aggressiveness with a high accuracy. The HSI-based radiomic method may provide a useful tool to aid oncologists in determining tumors with intermediate to high risk and in clinical decision making.

5.
Artigo em Inglês | MEDLINE | ID: mdl-36798940

RESUMO

The study is to incorporate polarized hyperspectral imaging (PHSI) with deep learning for automatic detection of head and neck squamous cell carcinoma (SCC) on hematoxylin and eosin (H&E) stained tissue slides. A polarized hyperspectral imaging microscope had been developed in our group. In this paper, we firstly collected the Stokes vector data cubes (S0, S1, S2, and S3) of histologic slides from 17 patients with SCC by the PHSI microscope, under the wavelength range from 467 nm to 750 nm. Secondly, we generated the synthetic RGB images from the original Stokes vector data cubes. Thirdly, we cropped the synthetic RGB images into image patches at the image size of 96×96 pixels, and then set up a ResNet50-based convolutional neural network (CNN) to classify the image patches of the four Stokes vector parameters (S0, S1, S2, and S3) by application of transfer learning. To test the performances of the model, each time we trained the model based on the image patches (S0, S1, S2, and S3) of 16 patients out of 17 patients, and used the trained model to calculate the testing accuracy based on the image patches of the rest 1 patient (S0, S1, S2, and S3). We repeated the process for 6 times and obtained 24 testing accuracies (S0, S1, S2, and S3) from 6 different patients out of the 17 patients. The preliminary results showed that the average testing accuracy (84.2%) on S3 outperformed the average testing accuracy (83.5%) on S0. Furthermore, 4 of 6 testing accuracies of S3 (96.0%, 87.3%, 82.8%, and 86.7%) outperformed the testing accuracies of S0 (93.3%, 85.2%, 80.2%, and 79.0%). The study demonstrated the potential of using polarized hyperspectral imaging and deep learning for automatic detection of head and neck SCC on pathologic slides.

6.
Int J Cardiovasc Imaging ; 38(12): 2667-2676, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36445665

RESUMO

The impact of mitral regurgitation (MR) from pediatric rheumatic heart disease (RHD) and its effect on left ventricular (LV) remodeling and function following surgical intervention is uncertain. The objective is to explore the impact of mitral valve (MV) surgeries on myocardial mechanics, remodeling and function and identify pre-operative predictors of post-operative dysfunction which may contribute to the optimal timing of intervention. A retrospective review of echocardiographic data was performed of eighteen pediatric patients with RHD (median 9yrs, IQR 6-12) who underwent MV surgery. Echocardiograms pre-operatively and a median of 13.5 months (IQR 10.2-15) following intervention were compared to controls. Pre-operative LV end-diastolic indexed volumes (LVEDVi) were significantly increased compared to controls and remained persistently larger post-operatively. LV ejection fraction (LVEF) (pre 62.6% ± 6.1, post 51.7% ± 9.7, p = 0.002), and global longitudinal strain (GLS) (pre - 24.3 ± 4.1, post - 18.2 ± 2.6, p < 0.001) decreased post-operatively at mid-term follow-up. Pre-operative LVEDVi was a significant predictor of post-operative LVEF, with a cut-off of ≥ 102 ml/m2 associated with LV dysfunction (LVEF < 55%; sensitivity 70%, specificity 75%). Pre-operative LVEDVi also negatively correlated with GLS (r = - 0.58, p = 0.01). LV dimensions and volumes remain persistently larger than controls while LV function decreases post-surgical alleviation of MR in paediatric RHD. Pre-operative LVEDVi predicted post-operative LV dysfunction and utilising LV indexed volumes in directing timing of surgical planning should be considered. Further studies are required to investigate whether timely alleviation of MR before significant LV dilatation and remodeling occur may substantially prevent LV dysfunction and improve outcomes.


Assuntos
Insuficiência da Valva Mitral , Cardiopatia Reumática , Disfunção Ventricular Esquerda , Humanos , Criança , Cardiopatia Reumática/complicações , Cardiopatia Reumática/diagnóstico por imagem , Cardiopatia Reumática/cirurgia , Remodelação Ventricular , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/etiologia , Insuficiência da Valva Mitral/cirurgia , Valor Preditivo dos Testes , Função Ventricular Esquerda , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia
7.
Environ Sci Eur ; 34(1): 104, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36284750

RESUMO

Background: The NORMAN Association (https://www.norman-network.com/) initiated the NORMAN Suspect List Exchange (NORMAN-SLE; https://www.norman-network.com/nds/SLE/) in 2015, following the NORMAN collaborative trial on non-target screening of environmental water samples by mass spectrometry. Since then, this exchange of information on chemicals that are expected to occur in the environment, along with the accompanying expert knowledge and references, has become a valuable knowledge base for "suspect screening" lists. The NORMAN-SLE now serves as a FAIR (Findable, Accessible, Interoperable, Reusable) chemical information resource worldwide. Results: The NORMAN-SLE contains 99 separate suspect list collections (as of May 2022) from over 70 contributors around the world, totalling over 100,000 unique substances. The substance classes include per- and polyfluoroalkyl substances (PFAS), pharmaceuticals, pesticides, natural toxins, high production volume substances covered under the European REACH regulation (EC: 1272/2008), priority contaminants of emerging concern (CECs) and regulatory lists from NORMAN partners. Several lists focus on transformation products (TPs) and complex features detected in the environment with various levels of provenance and structural information. Each list is available for separate download. The merged, curated collection is also available as the NORMAN Substance Database (NORMAN SusDat). Both the NORMAN-SLE and NORMAN SusDat are integrated within the NORMAN Database System (NDS). The individual NORMAN-SLE lists receive digital object identifiers (DOIs) and traceable versioning via a Zenodo community (https://zenodo.org/communities/norman-sle), with a total of > 40,000 unique views, > 50,000 unique downloads and 40 citations (May 2022). NORMAN-SLE content is progressively integrated into large open chemical databases such as PubChem (https://pubchem.ncbi.nlm.nih.gov/) and the US EPA's CompTox Chemicals Dashboard (https://comptox.epa.gov/dashboard/), enabling further access to these lists, along with the additional functionality and calculated properties these resources offer. PubChem has also integrated significant annotation content from the NORMAN-SLE, including a classification browser (https://pubchem.ncbi.nlm.nih.gov/classification/#hid=101). Conclusions: The NORMAN-SLE offers a specialized service for hosting suspect screening lists of relevance for the environmental community in an open, FAIR manner that allows integration with other major chemical resources. These efforts foster the exchange of information between scientists and regulators, supporting the paradigm shift to the "one substance, one assessment" approach. New submissions are welcome via the contacts provided on the NORMAN-SLE website (https://www.norman-network.com/nds/SLE/). Supplementary Information: The online version contains supplementary material available at 10.1186/s12302-022-00680-6.

8.
J Spinal Cord Med ; 34(2): 227-32, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21675361

RESUMO

STUDY DESIGN: Retrospective chart review. OBJECTIVE: To define the temporal course of weight gain in persons with new spinal cord injury (SCI), and to identify predictors of weight gain in this population. SETTING: A United States Department of Veterans Affairs (VA) SCI Unit. METHODS: A retrospective chart review in a VA SCI Unit was conducted. Participants (n = 85) included all persons with new SCI completing initial rehabilitation at the center between 1998 and 2006. Outcome measures were mean change in body mass index (BMI) between rehabilitation admission and final follow-up, time of greatest BMI change, and distribution of participants by BMI classification. These measures were also examined relative to SCI level, American Spinal Injury Association Impairment Scale (AIS) grade, primary mode of mobility, and age at rehabilitation admission. RESULTS: Mean BMI increased by 2.3 kg/m2 between rehabilitation admission (mean 45 days post-injury) and final follow-up (mean 5 years post-injury). The distribution of participants shifted from lower BMI classifications at rehabilitation admission to higher BMI classifications at final follow-up. For participants transitioning from normal to overweight or obese, the greatest increase occurred during the first year after acute rehabilitation. Neurological level, impairment category, primary mode of mobility, and age at rehabilitation admission did not significantly predict BMI change. BMI at rehabilitation admission correlated significantly with BMI at final follow-up (P < 0.0005). CONCLUSIONS: These findings confirm a significant increase in BMI after new SCI and suggest that persons with new SCI are at greatest weight gain risk during the first year following acute rehabilitation.


Assuntos
Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/reabilitação , Aumento de Peso/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Retrospectivos , Fatores de Tempo , Estados Unidos , United States Department of Veterans Affairs , Adulto Jovem
9.
Artigo em Inglês | MEDLINE | ID: mdl-35756897

RESUMO

Papillary thyroid carcinoma (PTC) is primarily treated by surgical resection. During surgery, surgeons often need intraoperative frozen analysis and pathologic consultation in order to detect PTC. In some cases pathologists cannot determine if the tumor is aggressive until the operation has been completed. In this work, we have taken tumor classification a step further by determining the tumor aggressiveness of fresh surgical specimens. We employed hyperspectral imaging (HSI) in combination with multiparametric radiomic features to complete this task. The study cohort includes 72 ex-vivo tissue specimens from 44 patients with pathology-confirmed PTC. A total of 67 features were extracted from this data. Using machine learning classification methods, we were able to achieve an AUC of 0.85. Our study shows that hyperspectral imaging and multiparametric radiomic features could aid in the pathological detection of tumor aggressiveness using fresh surgical spemens obtained during surgery.

10.
Artigo em Inglês | MEDLINE | ID: mdl-35755403

RESUMO

Surgery is a major treatment method for squamous cell carcinoma (SCC). During surgery, insufficient tumor margin may lead to local recurrence of cancer. Hyperspectral imaging (HSI) is a promising optical imaging technique for in vivo cancer detection and tumor margin assessment. In this study, a fully convolutional network (FCN) was implemented for tumor classification and margin assessment on hyperspectral images of SCC. The FCN was trained and validated with hyperspectral images of 25 ex vivo SCC surgical specimens from 20 different patients. The network was evaluated per patient and achieved pixel-level tissue classification with an average area under the curve (AUC) of 0.88, as well as 0.83 accuracy, 0.84 sensitivity, and 0.70 specificity across all the 20 patients. The 95% Hausdorff distance of assessed tumor margin in 17 patients was less than 2 mm, and the classification time of each tissue specimen took less than 10 seconds. The proposed methods can potentially facilitate intraoperative tumor margin assessment and improve surgical outcomes.

11.
Artigo em Inglês | MEDLINE | ID: mdl-35783088

RESUMO

The purpose of this study is to investigate hyperspectral microscopic imaging and deep learning methods for automatic detection of head and neck squamous cell carcinoma (SCC) on histologic slides. Hyperspectral imaging (HSI) cubes were acquired from pathologic slides of 18 patients with SCC of the larynx, hypopharynx, and buccal mucosa. An Inception-based two-dimensional convolutional neural network (CNN) was trained and validated for the HSI data. The automatic deep learning method was tested with independent data of human patients. This study demonstrated the feasibility of using hyperspectral microscopic imaging and deep learning classification to aid pathologists in detecting SCC on histologic slides.

12.
Artigo em Inglês | MEDLINE | ID: mdl-34955584

RESUMO

The aim of this study is to incorporate polarized hyperspectral imaging (PHSI) with machine learning for automatic detection of head and neck squamous cell carcinoma (SCC) on hematoxylin and eosin (H&E) stained tissue slides. A polarized hyperspectral imaging microscope had been developed in our group. In this paper, we imaged 20 H&E stained tissue slides from 10 patients with SCC of the larynx by the PHSI microscope. Several machine learning algorithms, including support vector machine (SVM), random forest, Gaussian naive Bayes, and logistic regression, were applied to the collected image data for the automatic detection of SCC on the H&E stained tissue slides. The performance of these methods was compared among the collected PHSI data, the pseudo-RGB images generated from the PHSI data, and the PHSI data after applying the principal component analysis (PCA) transformation. The results suggest that SVM is a superior classifier for the classification task based on the PHSI data cubes compared to the other three classifiers. The incorporate of four Stokes vector parameters improved the classification accuracy. Finally, the PCA transformed image data did not improve the accuracy as it might lose some important information from the original PHSI data. The preliminary results show that polarized hyperspectral imaging can have many potential applications in digital pathology.

13.
Inorg Chem ; 49(10): 4606-10, 2010 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-20397646

RESUMO

The thermal decomposition of [py(3)Co(3)O(OAc)(5)OH][PF(6)] in acetic acid solution in the absence of oxygen produced carbon dioxide, methane, carbon monoxide, picoline, and formic acid as the major products. The ratio of the products was affected by the water concentration and acidity of the mixture. Increased water concentration caused a decrease in methane and an increase in carbon monoxide. Decreased acidity resulted in an increase in methane and a decrease in carbon monoxide. Isotopic labeling experiments showed that some of the carbon monoxide originated as the carboxyl group of the acetic acid. Labeling experiments also showed that formaldehyde and formic acid could be converted to carbon monoxide under the reaction conditions. Two pathways leading to the formation of carbon monoxide were proposed; one involving the decomposition of glyoxylic acid and another involving the oxidation of the methyl radical by cobalt(III).

14.
Biomed Opt Express ; 11(3): 1383-1400, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32206417

RESUMO

The performance of hyperspectral imaging (HSI) for tumor detection is investigated in ex-vivo specimens from the thyroid (N = 200) and salivary glands (N = 16) from 82 patients. Tissues were imaged with HSI in broadband reflectance and autofluorescence modes. For comparison, the tissues were imaged with two fluorescent dyes. Additionally, HSI was used to synthesize three-band RGB multiplex images to represent the human-eye response and Gaussian RGBs, which are referred to as HSI-synthesized RGB images. Using histological ground truths, deep learning algorithms were developed for tumor detection. For the classification of thyroid tumors, HSI-synthesized RGB images achieved the best performance with an AUC score of 0.90. In salivary glands, HSI had the best performance with 0.92 AUC score. This study demonstrates that HSI could aid surgeons and pathologists in detecting tumors of the thyroid and salivary glands.

15.
Artigo em Inglês | MEDLINE | ID: mdl-32476709

RESUMO

Squamous cell carcinoma (SCC) comprises over 90 percent of tumors in the head and neck. The diagnosis process involves performing surgical resection of tissue and creating histological slides from the removed tissue. Pathologists detect SCC in histology slides, and may fail to correctly identify tumor regions within the slides. In this study, a dataset of patches extracted from 200 digitized histological images from 84 head and neck SCC patients was used to train, validate and test the segmentation performance of a fully-convolutional U-Net architecture. The neural network achieved a pixel-level segmentation AUC of 0.89 on the testing group. The average segmentation time for whole slide images was 72 seconds. The training, validation, and testing process in this experiment produces a model that has the potential to help segment SCC images in histological images with improved speed and accuracy compared to the manual segmentation process performed by pathologists.

16.
Syst Rev ; 9(1): 98, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32354349

RESUMO

BACKGROUND: Gasless laparoscopy, developed in the early 1990s, was a means to minimize the clinical and financial challenges of pneumoperitoneum and general anaesthesia. It has been used in a variety of procedures such as in general surgery and gynecology procedures including diagnostic laparoscopy. There has been increasing evidence of the utility of gasless laparoscopy in resource limited settings where diagnostic imaging is not available. In addition, it may help save costs for hospitals. The aim of this study is to conduct a systematic review of the available evidence surrounding the safety and efficiency of gasless laparoscopy compared to conventional laparoscopy and open techniques and to analyze the benefits that gasless laparoscopy has for low resource setting hospitals. METHODS: This protocol is developed by following the Preferred Reporting Items for Systematic review and Meta-Analysis-Protocols (PRISMA-P). The PRISMA statement guidelines and flowchart will be used to conduct the study itself. MEDLINE (Ovid), Embase, Web of Science, Cochrane Central, and Global Index Medicus (WHO) will be searched and the National Institutes of Health Clinical Trials database. The articles that will be found will be pooled into Covidence article manager software where all the records will be screened for eligibility and duplicates removed. A data extraction spreadsheet will be developed based on variables of interest set a priori. Reviewers will then screen all included studies based on the eligibility criteria. The GRADE tool will be used to assess the quality of the studies and the risk of bias in all the studies will be assessed using the Cochrane Risk assessment tool. The RoB II tool will assed the risk of bias in randomized control studies and the ROBINS I will be used for the non-randomized studies. DISCUSSION: This study will be a comprehensive review on all published articles found using this search strategy on the safety and efficiency of the use of gasless laparoscopy. The systematic review outcomes will include safety and efficiency of gasless laparoscopy compared to the use of conventional laparoscopy or laparotomy. TRIAL REGISTRATION: The study has been registered in PROSPERO under registration number: CRD42017078338.


Assuntos
Laparoscopia , Abdome , Anestesia Geral , Humanos , Pneumoperitônio Artificial , Revisões Sistemáticas como Assunto , Estados Unidos
17.
J Clin Periodontol ; 36(12): 1004-10, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19929953

RESUMO

AIM: To identify periodontal bacterial DNA (PBDNA) by PCR in subgingival dental plaque (SDP), serum and synovial fluid (SF) of rheumatoid arthritis (RA) with periodontal disease (PD) patients and to explore the possible PBDNA transport pathways from mouth to joints. METHODS: This cross-sectional prolective study involved 19 subjects with RA and PD. Informed consent, health and dental questionnaires were obtained. SDP, SF and serum samples were obtained, and leucocytes were isolated from blood. DNA was extracted and PCR assays to detect main PD species were carried out. Cultures on agar plates and broth, from each sample, were performed. RESULTS: Hundred percentage of patients showed PBDNA in SDP and SF and 83.5% in serum. Prevotella intermedia (89.4% and 73.6%) and Porphyromonas gingivalis (57.8% and 42.1%) were the species most frequently detected in SDP and SF, respectively. In SDP, 4.05 different bacterial species were found followed by 1.19 in serum and 2.26 in SF. Culture onto agar plates and broth did not show any bacterial growth, leucocytes were not positive to PBDNA by PCR. CONCLUSION: This study suggests that PBDNA could have a role on the RA aetiology. The possible pathway of transport of PBDNA from mouth to joints could be via the free form of DNA.


Assuntos
Artrite Reumatoide/etiologia , Artrite Reumatoide/microbiologia , Periodontite Crônica/complicações , Periodontite Crônica/microbiologia , Placa Dentária/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Transporte Biológico , Estudos Transversais , DNA Bacteriano/análise , DNA Bacteriano/sangue , Placa Dentária/complicações , Feminino , Humanos , Leucócitos/microbiologia , Masculino , Pessoa de Meia-Idade , Porphyromonas gingivalis/isolamento & purificação , Prevotella intermedia/isolamento & purificação , Líquido Sinovial/microbiologia , Adulto Jovem
18.
J Biomed Opt ; 24(3): 1-9, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30891966

RESUMO

For patients undergoing surgical cancer resection of squamous cell carcinoma (SCCa), cancer-free surgical margins are essential for good prognosis. We developed a method to use hyperspectral imaging (HSI), a noncontact optical imaging modality, and convolutional neural networks (CNNs) to perform an optical biopsy of ex-vivo, surgical gross-tissue specimens, collected from 21 patients undergoing surgical cancer resection. Using a cross-validation paradigm with data from different patients, the CNN can distinguish SCCa from normal aerodigestive tract tissues with an area under the receiver operator curve (AUC) of 0.82. Additionally, normal tissue from the upper aerodigestive tract can be subclassified into squamous epithelium, muscle, and gland with an average AUC of 0.94. After separately training on thyroid tissue, the CNN can differentiate between thyroid carcinoma and normal thyroid with an AUC of 0.95, 92% accuracy, 92% sensitivity, and 92% specificity. Moreover, the CNN can discriminate medullary thyroid carcinoma from benign multinodular goiter (MNG) with an AUC of 0.93. Classical-type papillary thyroid carcinoma is differentiated from MNG with an AUC of 0.91. Our preliminary results demonstrate that an HSI-based optical biopsy method using CNNs can provide multicategory diagnostic information for normal and cancerous head-and-neck tissue, and more patient data are needed to fully investigate the potential and reliability of the proposed technique.


Assuntos
Biópsia/métodos , Interpretação de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Imagem Óptica/métodos , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagem , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/cirurgia
19.
Cancers (Basel) ; 11(9)2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31540063

RESUMO

Surgical resection of head and neck (H and N) squamous cell carcinoma (SCC) may yield inadequate surgical cancer margins in 10 to 20% of cases. This study investigates the performance of label-free, reflectance-based hyperspectral imaging (HSI) and autofluorescence imaging for SCC detection at the cancer margin in excised tissue specimens from 102 patients and uses fluorescent dyes for comparison. Fresh surgical specimens (n = 293) were collected during H and N SCC resections (n = 102). The tissue specimens were imaged with reflectance-based HSI and autofluorescence imaging and afterwards with two fluorescent dyes for comparison. A histopathological ground truth was made. Deep learning tools were developed to detect SCC with new patient samples (inter-patient) and machine learning for intra-patient tissue samples. Area under the curve (AUC) of the receiver-operator characteristic was used as the main evaluation metric. Additionally, the performance was estimated in mm increments circumferentially from the tumor-normal margin. In intra-patient experiments, HSI classified conventional SCC with an AUC of 0.82 up to 3 mm from the cancer margin, which was more accurate than proflavin dye and autofluorescence (both p < 0.05). Intra-patient autofluorescence imaging detected human papilloma virus positive (HPV+) SCC with an AUC of 0.99 at 3 mm and greater accuracy than proflavin dye (p < 0.05). The inter-patient results showed that reflectance-based HSI and autofluorescence imaging outperformed proflavin dye and standard red, green, and blue (RGB) images (p < 0.05). In new patients, HSI detected conventional SCC in the larynx, oropharynx, and nasal cavity with 0.85-0.95 AUC score, and autofluorescence imaging detected HPV+ SCC in tonsillar tissue with 0.91 AUC score. This study demonstrates that label-free, reflectance-based HSI and autofluorescence imaging methods can accurately detect the cancer margin in ex-vivo specimens within minutes. This non-ionizing optical imaging modality could aid surgeons and reduce inadequate surgical margins during SCC resections.

20.
Sci Rep ; 9(1): 14043, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31575946

RESUMO

Primary management for head and neck cancers, including squamous cell carcinoma (SCC), involves surgical resection with negative cancer margins. Pathologists guide surgeons during these operations by detecting cancer in histology slides made from the excised tissue. In this study, 381 digitized, histological whole-slide images (WSI) from 156 patients with head and neck cancer were used to train, validate, and test an inception-v4 convolutional neural network. The proposed method is able to detect and localize primary head and neck SCC on WSI with an AUC of 0.916 for patients in the SCC testing group and 0.954 for patients in the thyroid carcinoma testing group. Moreover, the proposed method is able to diagnose WSI with cancer versus normal slides with an AUC of 0.944 and 0.995 for the SCC and thyroid carcinoma testing groups, respectively. For comparison, we tested the proposed, diagnostic method on an open-source dataset of WSI from sentinel lymph nodes with breast cancer metastases, CAMELYON 2016, to obtain patch-based cancer localization and slide-level cancer diagnoses. The experimental design yields a robust method with potential to help create a tool to increase efficiency and accuracy of pathologists detecting head and neck cancers in histological images.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias da Mama/patologia , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Conjuntos de Dados como Assunto , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Metástase Linfática/patologia , Redes Neurais de Computação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Manejo de Espécimes , Neoplasias da Glândula Tireoide/patologia
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