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1.
Br J Dermatol ; 184(4): 722-730, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32479678

RESUMEN

BACKGROUND: The PROspective Cutaneous Lymphoma International Prognostic Index (PROCLIPI) study is a prospective analysis of an international database. Here we examine front-line treatments and quality of life (QoL) in patients with newly diagnosed mycosis fungoides (MF). OBJECTIVES: To identify (i) differences in first-line approaches according to tumour-nodes-metastasis-blood (TNMB) staging; (ii) parameters related to a first-line systemic approach and (iii) response rates and QoL measures. METHODS: In total, 395 newly diagnosed patients with early-stage MF (stage IA-IIA) were recruited from 41 centres in 17 countries between 1 January 2015 and 31 December 2018 following central clinicopathological review. RESULTS: The most common first-line therapy was skin-directed therapy (SDT) (322 cases, 81·5%), while a smaller percentage (44 cases, 11·1%) received systemic therapy. Expectant observation was used in 7·3%. In univariate analysis, the use of systemic therapy was significantly associated with higher clinical stage (IA, 6%; IB, 14%; IIA, 20%; IA-IB vs. IIA, P < 0·001), presence of plaques (T1a/T2a, 5%; T1b/T2b, 17%; P < 0·001), higher modified Severity Weighted Assessment Tool (> 10, 15%; ≤ 10, 7%; P = 0·01) and folliculotropic MF (FMF) (24% vs. 12%, P = 0·001). Multivariate analysis demonstrated significant associations with the presence of plaques (T1b/T2b vs. T1a/T2a, odds ratio 3·07) and FMF (odds ratio 2·83). The overall response rate (ORR) to first-line SDT was 73%, while the ORR to first-line systemic treatments was lower (57%) (P = 0·027). Health-related QoL improved significantly both in patients with responsive disease and in those with stable disease. CONCLUSIONS: Disease characteristics such as presence of plaques and FMF influence physician treatment choices, and SDT was superior to systemic therapy even in patients with such disease characteristics. Consequently, future treatment guidelines for early-stage MF need to address these issues.


Asunto(s)
Micosis Fungoide , Neoplasias Cutáneas , Humanos , Micosis Fungoide/patología , Micosis Fungoide/terapia , Estadificación de Neoplasias , Pronóstico , Estudios Prospectivos , Calidad de Vida , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/terapia
2.
Br J Dermatol ; 184(3): 524-531, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32574377

RESUMEN

BACKGROUND: Early-stage mycosis fungoides (MF) includes involvement of dermatopathic lymph nodes (LNs) or early lymphomatous LNs. There is a lack of unanimity among current guidelines regarding the indications for initial staging imaging in early-stage presentation of MF in the absence of enlarged palpable LNs. OBJECTIVES: To investigate how often imaging is performed in patients with early-stage presentation of MF, to assess the yield of LN imaging, and to determine what disease characteristics promoted imaging. METHODS: A review of clinicopathologically confirmed newly diagnosed patients with cutaneous patch/plaque (T1/T2) MF from PROspective Cutaneous Lymphoma International Prognostic Index (PROCLIPI) data. RESULTS: PROCLIPI enrolled 375 patients with stage T1/T2 MF: 304 with classical MF and 71 with folliculotropic MF. Imaging was performed in 169 patients (45%): 83 with computed tomography, 18 with positron emission tomography-computed tomography and 68 with ultrasound. Only nine of these (5%) had palpable enlarged (≥ 15 mm) LNs, with an over-representation of plaques, irrespectively of the 10% body surface area cutoff that distinguishes T1 from T2. Folliculotropic MF was not more frequently imaged than classical MF. Radiologically enlarged LNs (≥ 15 mm) were detected in 30 patients (18%); only seven had clinical lymphadenopathy. On multivariate analysis, plaque presentation was the sole parameter significantly associated with radiologically enlarged LNs. Imaging of only clinically enlarged LNs upstaged 4% of patients (seven of 169) to at least IIA, whereas nonselective imaging upstaged another 14% (24 of 169). LN biopsy, performed in eight of 30 patients, identified N3 (extensive lymphomatous involvement) in two and N1 (dermatopathic changes) in six. CONCLUSIONS: Physical examination was a poor determinant of LN enlargement or involvement. Presence of plaques was associated with a significant increase in identification of enlarged or involved LNs in patients with early-stage presentation of MF, which may be important when deciding who to image. Imaging increases the detection rate of stage IIA MF, and identifies rare cases of extensive lymphomatous nodes, upstaging them to advanced-stage IVA2.


Asunto(s)
Micosis Fungoide , Neoplasias Cutáneas , Humanos , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/patología , Micosis Fungoide/diagnóstico por imagen , Micosis Fungoide/patología , Estadificación de Neoplasias , Pronóstico , Estudios Prospectivos , Neoplasias Cutáneas/diagnóstico por imagen , Neoplasias Cutáneas/patología
3.
Rev Cardiovasc Med ; 21(4): 541-560, 2020 12 30.
Artículo en Inglés | MEDLINE | ID: mdl-33387999

RESUMEN

Artificial Intelligence (AI), in general, refers to the machines (or computers) that mimic "cognitive" functions that we associate with our mind, such as "learning" and "solving problem". New biomarkers derived from medical imaging are being discovered and are then fused with non-imaging biomarkers (such as office, laboratory, physiological, genetic, epidemiological, and clinical-based biomarkers) in a big data framework, to develop AI systems. These systems can support risk prediction and monitoring. This perspective narrative shows the powerful methods of AI for tracking cardiovascular risks. We conclude that AI could potentially become an integral part of the COVID-19 disease management system. Countries, large and small, should join hands with the WHO in building biobanks for scientists around the world to build AI-based platforms for tracking the cardiovascular risk assessment during COVID-19 times and long-term follow-up of the survivors.


Asunto(s)
Inteligencia Artificial , COVID-19/epidemiología , Enfermedades Cardiovasculares/epidemiología , Atención a la Salud/métodos , Pandemias , Medición de Riesgo , SARS-CoV-2 , Enfermedades Cardiovasculares/terapia , Comorbilidad , Humanos , Factores de Riesgo
4.
Br J Dermatol ; 182(3): 770-779, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31049926

RESUMEN

BACKGROUND: Mycosis fungoides (MF) and Sézary Syndrome (SS) are the most common cutaneous T-cell lymphomas. MF/SS is accompanied by considerable morbidity from pain, itching and disfigurement. AIM: To identify factors associated with poorer health-related quality of life (HRQoL) in patients newly diagnosed with MF/SS. METHODS: Patients enrolled into Prospective Cutaneous Lymphoma International Prognostic Index (PROCLIPI; an international observational study in MF/SS) had their HRQoL assessed using the Skindex-29 questionnaire. Skindex-29 scores were analysed in relation to patient- and disease-specific characteristics. RESULTS: The study population consisted of 237 patients [60·3% male; median age 60 years, (interquartile range 49-70)], of whom 179 had early MF and 58 had advanced MF/SS. In univariate analysis, HRQoL, as measured by Skindex-29, was worse in women, SS, late-stage MF, those with elevated lactate dehydrogenase, alopecia, high modified Severity Weighted Assessment Tool and confluent erythema. Linear regression models only identified female gender (ß = 8·61; P = 0·003) and alopecia (ß = 9·71, P = 0·02) as independent predictors of worse global HRQoL. Item-level analysis showed that the severe impairment in symptoms [odds ratio (OR) 2·14, 95% confidence interval (CI) 1·19-3·89] and emotions (OR 1·88, 95% CI 1·09-3·27) subscale scores seen in women was caused by more burning/stinging, pruritus, irritation and greater feelings of depression, shame, embarrassment and annoyance with their diagnosis of MF/SS. CONCLUSIONS: HRQoL is significantly more impaired in newly diagnosed women with MF/SS and in those with alopecia. As Skindex-29 does not include existential questions on cancer, which may cause additional worry and distress, a comprehensive validated cutaneous T-cell lymphoma-specific questionnaire is urgently needed to more accurately assess disease-specific HRQoL in these patients. What's already known about this topic? Cross-sectional studies of mixed populations of known and newly diagnosed patients with mycosis fungoides (MF)/Sézary syndrome (SS) have shown significant impairment in health-related quality of life (HRQoL). Previous studies on assessing gender-specific differences in HRQoL in MF/SS are conflicting. More advanced-stage disease and pruritus is associated with poorer HRQoL in patients with MF/SS. What does this study add? This is the first prospective study to investigate HRQoL in a homogenous group of newly diagnosed patients with MF/SS. In patients newly diagnosed with MF/SS, HRQoL is worse in women and in those with alopecia and confluent erythema. MF/SS diagnosis has a multidimensional impact on patient HRQoL, including a large burden of cutaneous symptoms, as well as a negative impact on emotional well-being.


Asunto(s)
Linfoma Cutáneo de Células T , Micosis Fungoide , Síndrome de Sézary , Neoplasias Cutáneas , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Calidad de Vida
5.
Ann Oncol ; 28(10): 2517-2525, 2017 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-28961843

RESUMEN

BACKGROUND: Advanced-stage mycosis fungoides (MF)/Sézary syndrome (SS) patients are weighted by an unfavorable prognosis and share an unmet clinical need of effective treatments. International guidelines are available detailing treatment options for the different stages but without recommending treatments in any particular order due to lack of comparative trials. The aims of this second CLIC study were to retrospectively analyze the pattern of care worldwide for advanced-stage MF/SS patients, the distribution of treatments according to geographical areas (USA versus non-USA), and whether the heterogeneity of approaches has potential impact on survival. PATIENTS AND METHODS: This study included 853 patients from 21 specialist centers (14 European, 4 USA, 1 each Australian, Brazilian, and Japanese). RESULTS: Heterogeneity of treatment approaches was found, with up to 24 different modalities or combinations used as first-line and 36% of patients receiving four or more treatments. Stage IIB disease was most frequently treated by total-skin-electron-beam radiotherapy, bexarotene and gemcitabine; erythrodermic and SS patients by extracorporeal photochemotherapy, and stage IVA2 by polychemotherapy. Significant differences were found between USA and non-USA centers, with bexarotene, photopheresis and histone deacetylase inhibitors most frequently prescribed for first-line treatment in USA while phototherapy, interferon, chlorambucil and gemcitabine in non-USA centers. These differences did not significantly impact on survival. However, when considering death and therapy change as competing risk events and the impact of first treatment line on both events, both monochemotherapy (SHR = 2.07) and polychemotherapy (SHR = 1.69) showed elevated relative risks. CONCLUSION: This large multicenter retrospective study shows that there exist a large treatment heterogeneity in advanced MF/SS and differences between USA and non-USA centers but these were not related to survival, while our data reveal that chemotherapy as first treatment is associated with a higher risk of death and/or change of therapy and thus other therapeutic options should be preferable as first treatment approach.


Asunto(s)
Micosis Fungoide/terapia , Síndrome de Sézary/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Australia/epidemiología , Brasil/epidemiología , Niño , Europa (Continente)/epidemiología , Femenino , Humanos , Japón/epidemiología , Masculino , Oncología Médica/métodos , Oncología Médica/estadística & datos numéricos , Persona de Mediana Edad , Micosis Fungoide/mortalidad , Micosis Fungoide/patología , Estadificación de Neoplasias , Estudios Retrospectivos , Síndrome de Sézary/mortalidad , Síndrome de Sézary/patología , Estados Unidos/epidemiología , Adulto Joven
6.
Appl Microbiol Biotechnol ; 101(19): 7187-7200, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28785897

RESUMEN

Processes catalyzed by enzymes offer numerous advantages over chemical methods although in many occasions the stability of the biocatalysts becomes a serious concern. Traditionally, synthesis of nucleosides using poorly water-soluble purine bases, such as guanine, xanthine, or hypoxanthine, requires alkaline pH and/or high temperatures in order to solubilize the substrate. In this work, we demonstrate that the 2'-deoxyribosyltransferase from Leishmania mexicana (LmPDT) exhibits an unusually high activity and stability under alkaline conditions (pH 8-10) across a broad range of temperatures (30-70 °C) and ionic strengths (0-500 mM NaCl). Conversely, analysis of the crystal structure of LmPDT together with comparisons with hexameric, bacterial homologues revealed the importance of the relationships between the oligomeric state and the active site architecture within this family of enzymes. Moreover, molecular dynamics and docking approaches provided structural insights into the substrate-binding mode. Biochemical characterization of LmPDT identifies the enzyme as a type I NDT (PDT), exhibiting excellent activity, with specific activity values 100- and 4000-fold higher than the ones reported for other PDTs. Interestingly, LmPDT remained stable during 36 h at different pH values at 40 °C. In order to explore the potential of LmPDT as an industrial biocatalyst, enzymatic production of several natural and non-natural therapeutic nucleosides, such as vidarabine (ara A), didanosine (ddI), ddG, or 2'-fluoro-2'-deoxyguanosine, was carried out using poorly water-soluble purines. Noteworthy, this is the first time that the enzymatic synthesis of 2'-fluoro-2'-deoxyguanosine, ara G, and ara H by a 2'-deoxyribosyltransferase is reported.


Asunto(s)
Leishmania mexicana/enzimología , Nucleósidos/biosíntesis , Pentosiltransferasa/metabolismo , Purinas/química , Secuencia de Aminoácidos , Biocatálisis , Clonación Molecular , Biología Computacional , Enzimas Inmovilizadas , Concentración de Iones de Hidrógeno , Leishmania mexicana/genética , Pentosiltransferasa/genética , Conformación Proteica , Alineación de Secuencia , Especificidad por Sustrato , Temperatura
7.
J Med Syst ; 41(10): 152, 2017 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-28836045

RESUMEN

Fatty Liver Disease (FLD) is caused by the deposition of fat in liver cells and leads to deadly diseases such as liver cancer. Several FLD detection and characterization systems using machine learning (ML) based on Support Vector Machines (SVM) have been applied. These ML systems utilize large number of ultrasonic grayscale features, pooling strategy for selecting the best features and several combinations of training/testing. As result, they are computationally intensive, slow and do not guarantee high performance due to mismatch between grayscale features and classifier type. This study proposes a reliable and fast Extreme Learning Machine (ELM)-based tissue characterization system (a class of Symtosis) for risk stratification of ultrasound liver images. ELM is used to train single layer feed forward neural network (SLFFNN). The input-to-hidden layer weights are randomly generated reducing computational cost. The only weights to be trained are hidden-to-output layer which is done in a single pass (without any iteration) making ELM faster than conventional ML methods. Adapting four types of K-fold cross-validation (K = 2, 3, 5 and 10) protocols on three kinds of data sizes: S0-original, S4-four splits, S8-sixty four splits (a total of 12 cases) and 46 types of grayscale features, we stratify the FLD US images using ELM and benchmark against SVM. Using the US liver database of 63 patients (27 normal/36 abnormal), our results demonstrate superior performance of ELM compared to SVM, for all cross-validation protocols (K2, K3, K5 and K10) and all types of US data sets (S0, S4, and S8) in terms of sensitivity, specificity, accuracy and area under the curve (AUC). Using the K10 cross-validation protocol on S8 data set, ELM showed an accuracy of 96.75% compared to 89.01% for SVM, and correspondingly, the AUC: 0.97 and 0.91, respectively. Further experiments also showed the mean reliability of 99% for ELM classifier, along with the mean speed improvement of 40% using ELM against SVM. We validated the symtosis system using two class biometric facial public data demonstrating an accuracy of 100%.


Asunto(s)
Hepatopatías , Algoritmos , Humanos , Redes Neurales de la Computación , Reproducibilidad de los Resultados , Máquina de Vectores de Soporte
8.
J Med Syst ; 42(1): 18, 2017 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-29218604

RESUMEN

The original version of this article unfortunately contained a mistake. The family name of Rui Tato Marinho was incorrectly spelled as Marinhoe.

9.
J Eur Acad Dermatol Venereol ; 29(9): 1822-7, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25727104

RESUMEN

BACKGROUND: Five per cent 5-fluorouracil (5-FU) cream is a well-established treatment for actinic keratosis (AK), and ingenol mebutate gel (IMB) is a novel topical field-directed therapy. OBJECTIVE: To compare the tolerability and safety of IMB with that of 5-FU for the treatment of facial AK. METHODS: An open-label, prospective, randomized, controlled clinical trial with 100 patients with AKs within a 25-cm(2) contiguous field on the face was conducted. IMB was applied daily for three consecutive days. 5-FU was applied twice a day for 4 weeks. The treatment effect and the adverse events were evaluated at baseline and on days 2, 3, 4, 8, 15, 22, 29, 36 and 43 for intent-to-treat populations. RESULTS: The mean (± SD) maximum local skin reactions (LSR) for patients treated with IMB was 10.85 (± 3.12), compared with 10.86 (± 3.55) for those who received 5-FU. Patients in the IMB group presented LSR that peaked at day 4 and almost completely regressed after 15 days. Differently, in the 5-FU group, the LSR peaked at day 29 and lasted until visit 36. Additionally, the area under the curve (LSR × visit) was significantly smaller for IMB. No differences between the treatments for pruritus, pain, tearing, conjunctival hyperaemia or headaches were noted, but the eyelid oedema rate was higher for IMB group. No significant difference in the proportion of dropouts was observed between groups. Both treatments demonstrated a suitable safety profile. CONCLUSION: For treating AKs, the local skin reactions in the IMB group were more short-lived compared with those of 5-FU, but both treatments seemed to be safe and tolerable.


Asunto(s)
Diterpenos/administración & dosificación , Tolerancia a Medicamentos , Dermatosis Facial/tratamiento farmacológico , Fluorouracilo/administración & dosificación , Queratosis Actínica/tratamiento farmacológico , Administración Tópica , Dermatosis Facial/diagnóstico , Estudios de Seguimiento , Geles , Humanos , Inmunosupresores/administración & dosificación , Queratosis Actínica/diagnóstico , Estudios Prospectivos , Factores de Tiempo , Resultado del Tratamiento
10.
J Eur Acad Dermatol Venereol ; 29(2): 298-306, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25065394

RESUMEN

BACKGROUND: Topical therapy is important in the treatment of actinic keratosis (AK), a major risk factor for, and early development stage of, squamous cell carcinoma. Despite this, research addressing the limitations and challenges associated with topical field therapy in actinic keratosis is lacking. OBJECTIVES: The aim of this study was to highlight the challenges associated with maximizing compliance in patients receiving topical AK therapy and to investigate real-world experience with currently available topical therapies including perceptions of adherence and persistence. METHODS: A 45-min online survey was developed and completed by physicians in eight countries. All had previously prescribed topical AK therapy and ≥1 other treatment. Physicians' consensus was summarized as overall agreement/disagreement from ≥70% of respondents (≥60% for case-specific questions). RESULTS: More than 70% of the 427 respondents agreed that topical field therapy is essential and had concerns that lengthy treatments and local skin reactions caused non-adherence/persistence. More than 90% of physicians would preferentially prescribe the shortest duration treatment to such patients. CONCLUSIONS: The research clarifies the challenges associated with prescribing topical AK therapy and highlights that short treatment duration and rapid clearance of skin reactions are key considerations for physicians. This provides a basis for the generation of recommendations for improving the real-world efficacy of topical therapy.


Asunto(s)
Actitud del Personal de Salud , Queratosis Actínica/tratamiento farmacológico , Médicos/psicología , Humanos , Encuestas y Cuestionarios
12.
Echocardiography ; 31(3): 353-61, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24117920

RESUMEN

Active carotid plaques are associated with atheroembolism and neurological events; its identification is crucial for stroke prevention. High-definition ultrasound (HDU) can be used to recognize plaque structure in carotid bifurcation stenosis associated with plaque vulnerability and occurrence of brain ischemic events. A new computer-assisted HDU method to study the echomorphology of the carotid plaque and to determine a risk score for developing appropriate symptoms is proposed in this study. Plaque echomorphology characteristics such as presence of ulceration at the plaque surface, juxta-luminal location of echolucent areas, echoheterogeneity were obtained from B-mode ultrasound scans using several image processing algorithms and were combined with measurement of severity of stenosis to obtain a clinical score--enhanced activity index (EAI)--which was correlated with the presence or absence of ipsilateral appropriate ischemic symptoms. An optimal cutoff value of EAI was determined to obtain the best separation between symptomatic (active) from asymptomatic (inactive) plaques and its diagnostic yield was compared to other 2 reference methods by means of receiver-operating characteristic (ROC) analysis. Classification performance was evaluated by leave-one-patient-out cross-validation applied to a cohort of 146 carotid plaques from 99 patients. The proposed method was benchmarked against (a) degree of stenosis criteria and (b) earlier proposed activity index (AI) and demonstrated that EAI yielded the highest accuracy up to an accuracy of 77% to predict asymptomatic plaques that developed symptoms in a prospective cross-sectional study. Enhanced activity index is a noninvasive, easy to obtain parameter, which provided accurate estimation of neurological risk of carotid plaques.


Asunto(s)
Estenosis Carotídea/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador , Placa Aterosclerótica/diagnóstico por imagen , Accidente Cerebrovascular/etiología , Ultrasonografía Doppler en Color/métodos , Anciano , Benchmarking , Estenosis Carotídea/complicaciones , Estenosis Carotídea/fisiopatología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Placa Aterosclerótica/complicaciones , Placa Aterosclerótica/fisiopatología , Valor Predictivo de las Pruebas , Estudios Prospectivos , Curva ROC , Medición de Riesgo , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/prevención & control
13.
Microsc Microanal ; 19(5): 1110-21, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23992353

RESUMEN

Fluorescence images present low signal-to-noise ratio (SNR), are corrupted by a type of multiplicative noise with Poisson distribution, and are affected by a time intensity decay due to photoblinking and photobleaching (PBPB) effects. The noise and the PBPB effects together make long-term biological observation very difficult. Here, a theoretical model based on the underlying quantum mechanic physics theory of the observation process associated with this type of image is presented and the common empirical weighted sum of two decaying exponentials is derived from the model. Improvement in the SNR obtained in denoising when the proposed method is used is particularly important in the last images of the sequence where temporal correlation is used to recover information that is sometimes faded and therefore useless from a visual inspection point of view. The proposed PBPB model is included in a Bayesian denoising algorithm previously proposed by the authors. Experiments with synthetic and real data are presented to validate the PBPB model and to illustrate the effectiveness of the model in denoising and reconstruction results.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Imagen Óptica/métodos , Núcleo Celular , Células HeLa , Humanos , Modelos Teóricos
14.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 204-207, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34891272

RESUMEN

Capturing the error perception of a human interacting with a Brain-Computer Interface (BCI) is a key piece in improving the accuracy of these systems and making the interaction more seamless. Convolutional Neural Networks (CNN) have recently been applied for this task rendering the model free of feature-selection. We propose a new model with shorter temporal input trying to approximate its usability to that of a real-time BCI application. We evaluate and compare our model with some other recent CNN models using the Monitoring Error-Related Potential dataset, obtaining an accuracy of 80% with a sensitivity and specificity of 76% and 85%, respectively. These results outperform previous models. All models are made available online for reproduction and peer review.


Asunto(s)
Interfaces Cerebro-Computador , Recolección de Datos , Electroencefalografía , Humanos , Redes Neurales de la Computación , Percepción
15.
Sci Rep ; 11(1): 17310, 2021 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-34453069

RESUMEN

We consider transport properties of a hybrid device composed by a quantum dot placed between normal and superconducting reservoirs, and coupled to a Majorana nanowire: a topological superconducting segment hosting Majorana bound states (MBSs) at the opposite ends. It is demonstrated that if highly nonlocal and nonoverlapping MBSs are formed in the system, the zero-bias Andreev conductance through the dot exhibits characteristic isoconductance profiles with the shape depending on the spin asymmetry of the coupling between the dot and the topological superconductor. Otherwise, for overlapping MBSs with less degree of nonlocality, the conductance is insensitive to the spin polarization and the isoconductance signatures disappear. This allows to propose an alternative experimental protocol for probing the nonlocality of the MBSs in Majorana nanowires.

16.
Comput Biol Med ; 130: 104210, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33550068

RESUMEN

COVID-19 has infected 77.4 million people worldwide and has caused 1.7 million fatalities as of December 21, 2020. The primary cause of death due to COVID-19 is Acute Respiratory Distress Syndrome (ARDS). According to the World Health Organization (WHO), people who are at least 60 years old or have comorbidities that have primarily been targeted are at the highest risk from SARS-CoV-2. Medical imaging provides a non-invasive, touch-free, and relatively safer alternative tool for diagnosis during the current ongoing pandemic. Artificial intelligence (AI) scientists are developing several intelligent computer-aided diagnosis (CAD) tools in multiple imaging modalities, i.e., lung computed tomography (CT), chest X-rays, and lung ultrasounds. These AI tools assist the pulmonary and critical care clinicians through (a) faster detection of the presence of a virus, (b) classifying pneumonia types, and (c) measuring the severity of viral damage in COVID-19-infected patients. Thus, it is of the utmost importance to fully understand the requirements of for a fast and successful, and timely lung scans analysis. This narrative review first presents the pathological layout of the lungs in the COVID-19 scenario, followed by understanding and then explains the comorbid statistical distributions in the ARDS framework. The novelty of this review is the approach to classifying the AI models as per the by school of thought (SoTs), exhibiting based on segregation of techniques and their characteristics. The study also discusses the identification of AI models and its extension from non-ARDS lungs (pre-COVID-19) to ARDS lungs (post-COVID-19). Furthermore, it also presents AI workflow considerations of for medical imaging modalities in the COVID-19 framework. Finally, clinical AI design considerations will be discussed. We conclude that the design of the current existing AI models can be improved by considering comorbidity as an independent factor. Furthermore, ARDS post-processing clinical systems must involve include (i) the clinical validation and verification of AI-models, (ii) reliability and stability criteria, and (iii) easily adaptable, and (iv) generalization assessments of AI systems for their use in pulmonary, critical care, and radiological settings.


Asunto(s)
Inteligencia Artificial , COVID-19/diagnóstico por imagen , Pulmón/diagnóstico por imagen , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Tomografía Computarizada por Rayos X , Humanos
17.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1428-1431, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-33018258

RESUMEN

Segmentation of cell nuclei in fluorescence microscopy images provides valuable information about the shape and size of the nuclei, its chromatin texture and DNA content. It has many applications such as cell tracking, counting and classification. In this work, we extended our recently proposed approach for nuclei segmentation based on deep learning, by adding to its input handcrafted features. Our handcrafted features introduce additional domain knowledge that nuclei are expected to have an approximately round shape. For round shapes the gradient vector of points at the border point to the center. To convey this information, we compute a map of gradient convergence to be used by the CNN as a new channel, in addition to the fluorescence microscopy image. We applied our method to a dataset of microscopy images of cells stained with DAPI. Our results show that with this approach we are able to decrease the number of missdetections and, therefore, increase the F1-Score when compared to our previously proposed approach. Moreover, the results show that faster convergence is obtained when handcrafted features are combined with deep learning.


Asunto(s)
Algoritmos , Aprendizaje Profundo , Núcleo Celular , Cromatina , Microscopía Fluorescente
18.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1432-1435, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-33018259

RESUMEN

The progression of cells through the cell cycle is a tightly regulated process and is known to be key in maintaining normal tissue architecture and function. Disruption of these orchestrated phases will result in alterations that can lead to many diseases including cancer. Regrettably, reliable automatic tools to evaluate the cell cycle stage of individual cells are still lacking, in particular at interphase. Therefore, the development of new tools for a proper classification are urgently needed and will be of critical importance for cancer prognosis and predictive therapeutic purposes. Thus, in this work, we aimed to investigate three deep learning approaches for interphase cell cycle staging in microscopy images: 1) joint detection and cell cycle classification of nuclei patches; 2) detection of cell nuclei patches followed by classification of the cycle stage; 3) detection and segmentation of cell nuclei followed by classification of cell cycle staging. Our methods were applied to a dataset of microscopy images of nuclei stained with DAPI. The best results (0.908 F1-Score) were obtained with approach 3 in which the segmentation step allows for an intensity normalization that takes into account the intensities of all nuclei in a given image. These results show that for a correct cell cycle staging it is important to consider the relative intensities of the nuclei. Herein, we have developed a new deep learning method for interphase cell cycle staging at single cell level with potential implications in cancer prognosis and therapeutic strategies.


Asunto(s)
Núcleo Celular , Aprendizaje Profundo , Ciclo Celular , División Celular , Interfase
19.
Comput Biol Med ; 124: 103960, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32919186

RESUMEN

Artificial intelligence (AI) has penetrated the field of medicine, particularly the field of radiology. Since its emergence, the highly virulent coronavirus disease 2019 (COVID-19) has infected over 10 million people, leading to over 500,000 deaths as of July 1st, 2020. Since the outbreak began, almost 28,000 articles about COVID-19 have been published (https://pubmed.ncbi.nlm.nih.gov); however, few have explored the role of imaging and artificial intelligence in COVID-19 patients-specifically, those with comorbidities. This paper begins by presenting the four pathways that can lead to heart and brain injuries following a COVID-19 infection. Our survey also offers insights into the role that imaging can play in the treatment of comorbid patients, based on probabilities derived from COVID-19 symptom statistics. Such symptoms include myocardial injury, hypoxia, plaque rupture, arrhythmias, venous thromboembolism, coronary thrombosis, encephalitis, ischemia, inflammation, and lung injury. At its core, this study considers the role of image-based AI, which can be used to characterize the tissues of a COVID-19 patient and classify the severity of their infection. Image-based AI is more important than ever as the pandemic surges and countries worldwide grapple with limited medical resources for detection and diagnosis.


Asunto(s)
Betacoronavirus , Lesiones Encefálicas/epidemiología , Infecciones por Coronavirus/epidemiología , Lesiones Cardíacas/epidemiología , Neumonía Viral/epidemiología , Inteligencia Artificial , Betacoronavirus/patogenicidad , Betacoronavirus/fisiología , Lesiones Encefálicas/clasificación , Lesiones Encefálicas/diagnóstico por imagen , COVID-19 , Prueba de COVID-19 , Técnicas de Laboratorio Clínico/métodos , Comorbilidad , Biología Computacional , Infecciones por Coronavirus/clasificación , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/diagnóstico por imagen , Aprendizaje Profundo , Lesiones Cardíacas/clasificación , Lesiones Cardíacas/diagnóstico por imagen , Humanos , Aprendizaje Automático , Pandemias/clasificación , Neumonía Viral/clasificación , Neumonía Viral/diagnóstico por imagen , Factores de Riesgo , SARS-CoV-2 , Índice de Severidad de la Enfermedad
20.
Front Biosci (Elite Ed) ; 11(1): 166-185, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-31136971

RESUMEN

Wilson's disease (WD) is an autosomal recessive disorder which is caused by poor excretion of copper in mammalian cells. In this review, various issues such as effective characterization of ATP7B genes, scope of gene network topology in genetic analysis, pattern recognition using different computing approaches and fusion possibilities in imaging and genetic dataset are discussed vividly. We categorized this study into three major sections: (A) WD genetics, (B) diagnosis guidelines and (3) treatment possibilities. We addressed the scope of advanced mathematical modelling paradigms for understanding common genetic sequences and dominating WD imaging biomarkers. We have also discussed current state-of-the-art software models for genetic sequencing. Further, we hypothesized that involvement of machine and deep learning techniques in the context of WD genetics and image processing for precise classification of WD. These computing procedures signify changing roles of various data transformation techniques with respect to supervised and unsupervised learning models.


Asunto(s)
ATPasas Transportadoras de Cobre/genética , Aprendizaje Profundo , Degeneración Hepatolenticular/diagnóstico por imagen , Degeneración Hepatolenticular/genética , Degeneración Hepatolenticular/terapia , Humanos
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