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1.
Sensors (Basel) ; 23(18)2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37765731

RESUMO

Oral capillaroscopy is a critical and non-invasive technique used to evaluate microcirculation. Its ability to observe small vessels in vivo has generated significant interest in the field. Capillaroscopy serves as an essential tool for diagnosing and prognosing various pathologies, with anatomic-pathological lesions playing a crucial role in their progression. Despite its importance, the utilization of videocapillaroscopy in the oral cavity encounters limitations due to the acquisition setup, encompassing spatial and temporal resolutions of the video camera, objective magnification, and physical probe dimensions. Moreover, the operator's influence during the acquisition process, particularly how the probe is maneuvered, further affects its effectiveness. This study aims to address these challenges and improve data reliability by developing a computerized support system for microcirculation analysis. The designed system performs stabilization, enhancement and automatic segmentation of capillaries in oral mucosal video sequences. The stabilization phase was performed by means of a method based on the coupling of seed points in a classification process. The enhancement process implemented was based on the temporal analysis of the capillaroscopic frames. Finally, an automatic segmentation phase of the capillaries was implemented with the additional objective of quantitatively assessing the signal improvement achieved through the developed techniques. Specifically, transfer learning of the renowned U-net deep network was implemented for this purpose. The proposed method underwent testing on a database with ground truth obtained from expert manual segmentation. The obtained results demonstrate an achieved Jaccard index of 90.1% and an accuracy of 96.2%, highlighting the effectiveness of the developed techniques in oral capillaroscopy. In conclusion, these promising outcomes encourage the utilization of this method to assist in the diagnosis and monitoring of conditions that impact microcirculation, such as rheumatologic or cardiovascular disorders.


Assuntos
Capilares , Doenças Cardiovasculares , Humanos , Capilares/diagnóstico por imagem , Angioscopia Microscópica/métodos , Reprodutibilidade dos Testes , Doenças Cardiovasculares/patologia , Veias , Processamento de Imagem Assistida por Computador/métodos
2.
Vaccines (Basel) ; 10(11)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36423073

RESUMO

Videocapillaroscopy allows the study of both the morphological and architectural structure of the microcirculation and its hemodynamic conditions; these parameters are directly involved in autoimmune and/or inflammatory pathologies. The purpose of this research, based on capillaroscopy, is to establish whether a patient who receives an anti-COVID 19 vaccine has any changes in their oral microcirculation. A complete capillaroscopic mapping of the oral cavity of the subjects examined was made; the investigated mucosa sites were the following: cheek, labial, chewing-gingival and back of the tongue. This study showed an increase in capillary density from the comparison between the mean labial capillary density of vaccinated patients and the reference mean capillary density value of the literature. The increase in capillary density is a sign that can be attributed to an increase in angiogenic activity. The EMA, GACVS and MHRA have reviewed the risk of thrombosis after vaccination, agreeing that the benefits outweigh the risks.

3.
Pediatr Rep ; 14(2): 293-311, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35736659

RESUMO

Coeliac disease (CD) is frequently underdiagnosed with a consequent heavy burden in terms of morbidity and health care costs. Diagnosis of CD is based on the evaluation of symptoms and anti-transglutaminase antibodies IgA (TGA-IgA) levels, with values above a tenfold increase being the basis of the biopsy-free diagnostic approach suggested by present guidelines. This study showcased the largest screening project for CD carried out to date in school children (n=20,000) aimed at assessing the diagnostic accuracy of minimally invasive finger prick point-of-care tests (POCT) which, combined with conventional celiac serology and the aid of an artificial intelligence-based system, may eliminate the need for intestinal biopsy. Moreover, this study delves deeper into the "coeliac iceberg" in an attempt to identify people with disorders who may benefit from a gluten-free diet, even in the absence of gastrointestinal symptoms, abnormal serology and histology. This was achieved by looking for TGA-IgA mucosal deposits in duodenal biopsy. This large European multidisciplinary health project paves the way to an improved quality of life for patients by reducing the costs for diagnosis due to delayed findings of CD and to offer business opportunities in terms of diagnostic tools and support.

4.
Elife ; 112022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35471185

RESUMO

Neutrophil extracellular traps (NETs) are web-like chromatin structures composed by dsDNA and histones, decorated with antimicrobial proteins. Their interaction with dendritic cells (DCs) allows DC activation and maturation toward presentation of NET-associated antigens. Differently from other types of cell death that imply protein denaturation, NETosis preserves the proteins localized onto the DNA threads for proper enzymatic activity and conformational status, including immunogenic epitopes. Besides neutrophils, leukemic cells can release extracellular traps displaying leukemia-associated antigens, prototypically mutant nucleophosmin (NPMc+) that upon mutation translocates from nucleolus to the cytoplasm localizing onto NET threads. We tested NPMc+ immunogenicity through a NET/DC vaccine to treat NPMc-driven myeloproliferation in transgenic and transplantable models. Vaccination with DC loaded with NPMc+ NET (NPMc+ NET/DC) reduced myeloproliferation in transgenic mice, favoring the development of antibodies to mutant NPMc and the induction of a CD8+ T-cell response. The efficacy of this vaccine was also tested in mixed NPMc/WT bone marrow (BM) chimeras in a competitive BM transplantation setting, where the NPMc+ NET/DC vaccination impaired the expansion of NPMc+ in favor of WT myeloid compartment. NPMc+ NET/DC vaccination also achieved control of an aggressive leukemia transduced with mutant NPMc, effectively inducing an antileukemia CD8 T-cell memory response.


Assuntos
Armadilhas Extracelulares , Leucemia , Animais , Armadilhas Extracelulares/metabolismo , Camundongos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Vacinação
5.
Artigo em Inglês | MEDLINE | ID: mdl-35055643

RESUMO

An Android/iOS application for low-cost mobile devices to aid in dental diagnosis through questionnaire and photos is presented in this paper. The main purposes of our app lie in the ease of use even for nonexperienced users, in the limited hardware requirements that allow a wide diffusion, and in the possibility to modify the questionnaire for different pathologies. This tool was developed in about a month at the beginning of the COVID-19 (SARS-CoV-2) pandemic and is still in use in Italy to allow support to patients without going to the hospital, if not strictly necessary.


Assuntos
COVID-19 , Telemedicina , Computadores de Mão , Humanos , Pandemias , SARS-CoV-2
6.
Cell Rep ; 36(11): 109694, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34525372

RESUMO

Chromatin organization plays a crucial role in tissue homeostasis. Heterochromatin relaxation and consequent unscheduled mobilization of transposable elements (TEs) are emerging as key contributors of aging and aging-related pathologies, including Alzheimer's disease (AD) and cancer. However, the mechanisms governing heterochromatin maintenance or its relaxation in pathological conditions remain poorly understood. Here we show that PIN1, the only phosphorylation-specific cis/trans prolyl isomerase, whose loss is associated with premature aging and AD, is essential to preserve heterochromatin. We demonstrate that this PIN1 function is conserved from Drosophila to humans and prevents TE mobilization-dependent neurodegeneration and cognitive defects. Mechanistically, PIN1 maintains nuclear type-B Lamin structure and anchoring function for heterochromatin protein 1α (HP1α). This mechanism prevents nuclear envelope alterations and heterochromatin relaxation under mechanical stress, which is a key contributor to aging-related pathologies.


Assuntos
Proteínas de Drosophila/metabolismo , Heterocromatina/metabolismo , Lamina Tipo B/metabolismo , Peptidilprolil Isomerase de Interação com NIMA/metabolismo , Peptidilprolil Isomerase/metabolismo , Estresse Mecânico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Células Cultivadas , Homólogo 5 da Proteína Cromobox/genética , Homólogo 5 da Proteína Cromobox/metabolismo , Elementos de DNA Transponíveis/genética , Drosophila/metabolismo , Proteínas de Drosophila/antagonistas & inibidores , Proteínas de Drosophila/genética , Humanos , Lamina Tipo B/química , Camundongos , Camundongos Endogâmicos C57BL , Peptidilprolil Isomerase de Interação com NIMA/antagonistas & inibidores , Peptidilprolil Isomerase de Interação com NIMA/genética , Neocórtex/citologia , Neocórtex/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Membrana Nuclear/química , Peptidilprolil Isomerase/antagonistas & inibidores , Peptidilprolil Isomerase/genética , Fosforilação , Interferência de RNA , RNA Interferente Pequeno/metabolismo
7.
J Clin Med ; 9(11)2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33198337

RESUMO

INTRODUCTION: Diabetic foot represents one of the most serious and expensive complications of diabetes and is subject to a high percentage of amputations that are almost always preceded by ulcers ascribable to neuropathy and/or vasculopathy. Videocapillaroscopy (VCS) can be a valuable aid in order to uncover morpho-structural anomalies in the vascular bed, both at the level of the oral mucosa and at the level of the terminal vessels of the lower limb. MATERIALS AND METHODS: Sixty subjects divided into 4 groups were enrolled: 15 healthy subjects; 15 patients with diabetes for more than 10 years without ulcerative foot lesions; 15 patients with neuropathic diabetic foot (clinical diagnosis, MDNS); 15 patients with ischemic diabetic foot (clinical diagnosis, ABI, lower limb doppler). A complete videocapillaroscopic mapping of the oral mucosa was carried out on each patient. The areas investigated were: labial mucosa, the retro-commissural region of the buccal mucosa, and the vestibular masticatory mucosa (II and V sextant). RESULTS: The analysis of the morphological and densitometric characteristics of the capillaries revealed the following: a significant reduction in capillary density in neuropathic (mean ± SD 7.32 ± 2.1) and ischemic patients (mean ± SD 4.32 ± 3.2) compared to the control group of patients (both diabetic mean ± SD 12.98 ± 3.1 and healthy mean ± SD 19.04 ± 3.16) (ANOVA test and Bonferroni t test p < 0.05); a reduction in the average length of the capillaries and a significant increase in tortuosity (ANOVA test and Bonferroni t test p < 0.05). In the neuropathic patients, a recurrent capillaroscopic pattern that we defined as "sun" was found, with capillaries arranged radially around an avascular area. CONCLUSIONS: The data obtained from this preliminary study suggest a potential diagnostic role of oral capillaroscopy in the early and subclinical identification of microangiopathic damage in patients with diabetic foot.

8.
EBioMedicine ; 61: 103055, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33096480

RESUMO

BACKGROUND: Intra-tumour heterogeneity in lymphoid malignancies encompasses selection of genetic events and epigenetic regulation of transcriptional programs. Clonal-related neoplastic cell populations are unsteadily subjected to immune editing and metabolic adaptations within different tissue microenvironments. How tissue-specific mesenchymal cells impact on the diversification of aggressive lymphoma clones is still unknown. METHODS: Combining in situ quantitative immunophenotypical analyses and RNA sequencing we investigated the intra-tumour heterogeneity and the specific mesenchymal modifications that are associated with A20 diffuse large B-cell lymphoma (DLBCL) cells seeding of different tissue microenvironments. Furthermore, we characterized features of lymphoma-associated stromatogenesis in human DLBCL samples using Digital Spatial Profiling, and established their relationship with prognostically relevant variables, such as MYC. FINDINGS: We found that the tissue microenvironment casts a relevant influence over A20 transcriptional landscape also impacting on Myc and DNA damage response programs. Extending the investigation to mice deficient for the matricellular protein SPARC, a stromal prognostic factor in human DLBCL, we demonstrated a different immune imprint on A20 cells according to stromal Sparc proficiency. Through Digital Spatial Profiling of 87 immune and stromal genes on human nodal DLBCL regions characterized by different mesenchymal composition, we demonstrate intra-lesional heterogeneity arising from diversified mesenchymal contextures and impacting on the stromal and immune milieu. INTERPRETATION: Our study provides experimental evidence that stromal microenvironment generates topological determinants of intra-tumour heterogeneity in DLBCL involving key transcriptional pathways such as Myc expression, damage response programs and immune checkpoints. FUNDING: This study has been supported by the Italian Foundation for Cancer Research (AIRC) (grants 15999 and 22145 to C. Tripodo) and by the University of Palermo.


Assuntos
Biomarcadores Tumorais , Heterogeneidade Genética , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Células Estromais/metabolismo , Microambiente Tumoral/genética , Animais , Linhagem Celular Tumoral , Biologia Computacional/métodos , Modelos Animais de Doenças , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Imunofenotipagem , Hibridização In Situ , Camundongos , Modelos Biológicos , Fenótipo , Prognóstico , Análise de Sequência de RNA , Células Estromais/patologia , Transcriptoma
9.
J Biomed Inform ; 108: 103490, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32640292

RESUMO

The methods developed in recent years for synthesising an ocular fundus can be been divided into two main categories. The first category of methods involves the development of an anatomical model of the eye, where artificial images are generated using appropriate parameters for modelling the vascular networks and fundus. The second type of method has been made possible by the development of deep learning techniques and improvements in the performance of hardware (especially graphics cards equipped with a large number of cores). The methodology proposed here to produce high-resolution synthetic fundus images is intended to be an alternative to the increasingly widespread use of generative adversarial networks to overcome the problems that arise in producing slightly modified versions of the same real images. This will allow the simulation of pathologies and the prediction of eye-related diseases. The proposed approach is based on the principle of least action and correctly places the vessels on the simulated eye fundus without using real morphometric information. An a posteriori analysis of the average characteristics such as the size, length, bifurcations, and endpoint positioning confirmed the substantial accuracy of the proposed approach compared to real data. A graphical user interface allows the user to make any changes in real time by controlling the positions of control points.


Assuntos
Processamento de Imagem Assistida por Computador , Vasos Retinianos , Fundo de Olho , Vasos Retinianos/diagnóstico por imagem
11.
Clin Cancer Res ; 23(17): 5149-5161, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28600479

RESUMO

Purpose: Osteosarcoma, the most common primary bone tumor, is characterized by an aggressive behavior with high tendency to develop lung metastases as well as by multiple genetic aberrations that have hindered the development of targeted therapies. New therapeutic approaches are urgently needed; however, novel combinations with immunotherapies and checkpoint inhibitors require suitable preclinical models with intact immune systems to be properly tested.Experimental Design: We have developed immunocompetent osteosarcoma models that grow orthotopically in the bone and spontaneously metastasize to the lungs, mimicking human osteosarcoma. These models have been used to test the efficacy of trabectedin, a chemotherapeutic drug utilized clinically for sarcomas and ovarian cancer.Results: Trabectedin, as monotherapy, significantly inhibited osteosarcoma primary tumor growth and lung metastases by both targeting neoplastic cells and reprogramming the tumor immune microenvironment. Specifically, trabectedin induced a striking differentiation of tumor cells by favoring the recruitment of Runx2, the master genetic regulator of osteoblastogenesis, on the promoter of genes involved in the physiologic process of terminal osteoblast differentiation. Differentiated neoplastic cells, as expected, showed reduced proliferation rate. Concomitantly, trabectedin enhanced the number of tumor-infiltrating T lymphocytes, with local CD8 T cells, however, likely post-activated or exhausted, as suggested by their high expression of the inhibitory checkpoint molecule PD-1. Accordingly, the combination with a PD-1-blocking antibody significantly increased trabectedin efficacy in controlling osteosarcoma progression.Conclusions: These results demonstrate the therapeutic efficacy of trabectedin in osteosarcoma treatment, unveiling its multiple activities and providing a solid rationale for its combination with immune checkpoint inhibitors. Clin Cancer Res; 23(17); 5149-61. ©2017 AACR.


Assuntos
Neoplasias Ósseas/tratamento farmacológico , Dioxóis/efeitos adversos , Neoplasias Pulmonares/tratamento farmacológico , Osteossarcoma/tratamento farmacológico , Tetra-Hidroisoquinolinas/efeitos adversos , Neoplasias Ósseas/genética , Neoplasias Ósseas/imunologia , Neoplasias Ósseas/patologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Reprogramação Celular/efeitos dos fármacos , Reprogramação Celular/imunologia , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Dioxóis/administração & dosagem , Humanos , Imunoterapia/métodos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Osteossarcoma/genética , Osteossarcoma/imunologia , Osteossarcoma/patologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Tetra-Hidroisoquinolinas/administração & dosagem , Trabectedina , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Proteína Supressora de Tumor p53/genética
12.
Comput Biol Med ; 82: 12-20, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28126630

RESUMO

In this paper we propose a new methodology to support the physician both to identify automatically the nuchal region and to obtain a correct thickness measurement of the nuchal translucency. The thickness of the nuchal translucency is one of the main markers for screening of chromosomal defects such as trisomy 13, 18 and 21. Its measurement is performed during ultrasound scanning in the first trimester of pregnancy. The proposed methodology is mainly based on wavelet and multi resolution analysis. The performance of our method was analysed on 382 random frames, representing mid-sagittal sections, uniformly extracted from real clinical ultrasound videos of 12 patients. According to the ground-truth provided by an expert physician, we obtained a true positive rate equal to 99.95% with respect to the nuchal region detection and about 64% of measurements present an error equal to 1 pixel (which corresponds to 0.1mm), respectively.


Assuntos
Algoritmos , Síndrome de Down/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Aprendizado de Máquina , Medição da Translucência Nucal/métodos , Reconhecimento Automatizado de Padrão/métodos , Síndrome de Down/embriologia , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Análise de Ondaletas
13.
Comput Methods Programs Biomed ; 114(3): 240-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24657094

RESUMO

We aim to describe a new non-parametric methodology to support the clinician during the diagnostic process of oral videocapillaroscopy to evaluate peripheral microcirculation. Our methodology, mainly based on wavelet analysis and mathematical morphology to preprocess the images, segments them by minimizing the within-class luminosity variance of both capillaries and background. Experiments were carried out on a set of real microphotographs to validate this approach versus handmade segmentations provided by physicians. By using a leave-one-patient-out approach, we pointed out that our methodology is robust, according to precision-recall criteria (average precision and recall are equal to 0.924 and 0.923, respectively) and it acts as a physician in terms of the Jaccard index (mean and standard deviation equal to 0.858 and 0.064, respectively).


Assuntos
Capilares , Processamento de Imagem Assistida por Computador/métodos , Análise de Ondaletas , Algoritmos , Humanos , Microcirculação , Modelos Teóricos , Boca/irrigação sanguínea , Reprodutibilidade dos Testes
14.
Artigo em Inglês | MEDLINE | ID: mdl-25569919

RESUMO

Landmark points in retinal images can be used to create a graph representation to understand and to diagnose not only different pathologies of the eye, but also a variety of more general diseases. Aim of this paper is the description of a non-supervised methodology to distinguish between bifurcations and crossings of the retinal vessels, which can be used in differentiating between arteries and veins. A thinned representation of the binarized image, is used to identify pixels with three or more neighbors. Junction points are classified into bifurcations or crossovers according to their geometrical and topological properties. The proposed approach is successfully compared with the state-of-the-art methods with the benchmarks DRIVE and STARE. The recall, precision and F-score average detection values are 91.5%, 88.8% and 89.8% respectively.


Assuntos
Interpretação de Imagem Assistida por Computador , Vasos Retinianos/patologia , Algoritmos , Humanos , Reconhecimento Automatizado de Padrão , Sensibilidade e Especificidade
15.
PLoS Comput Biol ; 9(3): e1003014, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23555237

RESUMO

In the olfactory bulb, lateral inhibition mediated by granule cells has been suggested to modulate the timing of mitral cell firing, thereby shaping the representation of input odorants. Current experimental techniques, however, do not enable a clear study of how the mitral-granule cell network sculpts odor inputs to represent odor information spatially and temporally. To address this critical step in the neural basis of odor recognition, we built a biophysical network model of mitral and granule cells, corresponding to 1/100th of the real system in the rat, and used direct experimental imaging data of glomeruli activated by various odors. The model allows the systematic investigation and generation of testable hypotheses of the functional mechanisms underlying odor representation in the olfactory bulb circuit. Specifically, we demonstrate that lateral inhibition emerges within the olfactory bulb network through recurrent dendrodendritic synapses when constrained by a range of balanced excitatory and inhibitory conductances. We find that the spatio-temporal dynamics of lateral inhibition plays a critical role in building the glomerular-related cell clusters observed in experiments, through the modulation of synaptic weights during odor training. Lateral inhibition also mediates the development of sparse and synchronized spiking patterns of mitral cells related to odor inputs within the network, with the frequency of these synchronized spiking patterns also modulated by the sniff cycle.


Assuntos
Modelos Neurológicos , Neurônios/fisiologia , Odorantes , Bulbo Olfatório/fisiologia , Sinapses/fisiologia , Animais , Biologia Computacional , Simulação por Computador , Retroalimentação Fisiológica , Masculino , Rede Nervosa/citologia , Rede Nervosa/fisiologia , Plasticidade Neuronal , Bulbo Olfatório/citologia , Ratos
16.
Med Image Anal ; 12(6): 703-12, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18550417

RESUMO

This work describes an automatic method for discrimination in microphotographs between normal and pathological human megakaryocytes and between two kinds of disorders of these cells. A segmentation procedure has been developed, mainly based on mathematical morphology and wavelet transform, to isolate the cells. The features of each megakaryocyte (e.g. area, perimeter and tortuosity of the cell and its nucleus, and shape complexity via elliptic Fourier transform) are used by a regression tree procedure applied twice: the first time to find the set of normal megakaryocytes and the second to distinguish between the pathologies. The output of our classifier has been compared to the interpretation provided by the pathologists and the results show that 98.4% and 97.1% of normal and pathological cells, respectively, have testified an excellent classification. This study proposes a useful aid in supporting the specialist in the classification of megakaryocyte disorders.


Assuntos
Algoritmos , Inteligência Artificial , Interpretação de Imagem Assistida por Computador/métodos , Megacariócitos/classificação , Megacariócitos/patologia , Transtornos Mieloproliferativos/patologia , Reconhecimento Automatizado de Padrão/métodos , Animais , Células Cultivadas , Humanos , Aumento da Imagem/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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