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1.
Artigo em Inglês | MEDLINE | ID: mdl-38636827

RESUMO

INTRODUCTION AND OBJECTIVES: Lung cancer is the second type of cancer with the second highest incidence rate and the first with the highest mortality rate in the world. Machine learning through the analysis of imaging tests such as positron emission tomography/computed tomography (PET/CT) has become a fundamental tool for the early and accurate detection of cancer. The objective of this study was to propose an image analysis architecture (PET/CT) ordered in phases through the application of ensemble or combined machine learning methods for the early detection of lung cancer by analyzing PET/CT images. MATERIAL AND METHODS: A retrospective observational study was conducted utilizing a public dataset entitled "A large-scale CT and PET/CT dataset for lung cancer diagnosis." Various imaging modalities, including CT, PET, and fused PET/CT images, were employed. The architecture or framework of this study comprised the following phases: 1. Image loading or collection, 2. Image selection, 3. Image transformation, and 4. Balancing the frequency distribution of image classes. Predictive models for lung cancer detection using PET/CT images included: a) the Stacking model, which used Random Forest and Support Vector Machine (SVM) as base models and complemented them with a logistic regression model, and b) the Boosting model, which employed the Adaptive Boosting (AdaBoost) model for comparison with the Stacking model. Quality metrics used for evaluation included accuracy, precision, recall, and F1-score. RESULTS: This study showed a general performance of 94% with the Stacking method and a general performance of 77% with the Boosting method. CONCLUSIONS: The Stacking method proved to be a model with high performance and quality for lung cancer detection when analyzing PET/CT images.

4.
J Mater Sci Mater Med ; 34(8): 40, 2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37515640

RESUMO

The present work studies the effect of Mn doping on the crystalline structure of the Hap synthesized by the hydrothermal method at 200 °C for 24 h, from Ca(OH)2 and (NH4)2HPO4, incorporating MnCl2 to 0.1, 0.5, 1.0, 1.5 and 2.0 %wt of Mn concentrations. Samples were characterized by the X-Ray Diffraction technique, which revealed the diffraction peaks that corresponded to the hexagonal and monoclinic phase of the Hap; it was observed that the average size of crystallite decreased from 23.67 to 22.69 nm as the concentration of Mn increased. TEM shows that in all samples, there are two distributions of particle sizes; one corresponds to nanorods with several tens of nanometers in length, and the other in which the diameter and length are very close. FTIR analysis revealed absorption bands corresponding to the PO4-3 and OH- groups characteristic of the Hap. It was possible to establish a substitution mechanism between the Mn and the ions of Ca+2 of the Hap. From the Alamar blue test, a cell viability of 86.88% ± 5 corresponding to the sample of Hap at 1.5 %wt Mn was obtained, considered non-cytotoxic according to ISO 10993-5. It also evaluated and demonstrated the good osteoinductive properties of the materials, which were verified by histology and immunofluorescence expression of osteogenic markers. Adhesion, viability, biocompatibility and osteoinductive properties, make these materials candidates for future applications in bone tissue engineering with likely uses in regenerative medicine.


Assuntos
Durapatita , Nanotubos , Durapatita/química , Osteogênese
7.
Rev. argent. dermatol ; 104: 1-10, ene. 2023. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1431487

RESUMO

Resumen El melanoma primariovariedad rabdoide es unapresentación pocofrecuente.Reconocido como un subtipo histopatológico distinto de melanoma maligno generalmente observado en tumores metastásicos o recurrentes.El diagnóstico definitivo requiere el estudio de inmunomarcación y la identificación de células neoplásicas con marcadores melanocíticos. Clínicamente se han reportado mayormente de tipo nodular y amelanótico.


Summary Rhabdoid melanoma has been recognized as a histopathological subtype of malignant melanoma. It generally presents as a recurrent tumor, so its presentation as a primary lesion is infrecuent.Definitive diagnosis requires the study of immunostaining and the identification of neoplastic cells with melanocytic markers. Clinically, mostly nodular and amelanotic types have been reported.

8.
Rev. int. med. cienc. act. fis. deporte ; 22(88): 877-891, dic. 2022. tab
Artigo em Espanhol | IBECS | ID: ibc-213730

RESUMO

La insatisfacción con la imagen corporal puede desencadenar preocupación excesiva por la estética conduciendo a una utilización indiscriminada de suplementos nutricionales. Por ello, el objetivo de este estudio fue investigar la relación entre percepción y conformidad de imagen corporal al uso de suplementos nutricionales en usuarios regulares de gimnasios de la región del Biobío, Chile. La investigación corresponde a un estudio analítico transversal realizado en el segundo semestre del año 2018, en el que participaron 262 personas mayores de 18 años. Se observó una asociación estadísticamente significativa entre el uso de suplementos nutricionales y la percepción de la imagen corporal (OR 0,58, IC95%0,34–0,98; p=0,045), y entre el uso de suplementos nutricionales y la conformidad con la imagen corporal (OR 0,43, IC95%0,25–0,75; p=0,003). En conclusión, a mayor disconformidad con la imagen corporal o la presencia de una percepción alterada de ésta, mayor es la probabilidad de consumir suplementos nutricionales. (AU)


Dissatisfaction with body image can trigger excessive concern for aesthetics aspects leading to indiscriminate use of nutritional supplements. Therefore, the objective of this study was to investigate the relationship between the perception and conformity of body image with the use of nutritional supplements in regular users of gyms in the Biobío region, Chile. The research corresponds to a cross-sectional analytical study conducted in the second half of the year 2018, in 262 participants over 18 years old. A statistically significant association between the use of nutritional supplements and the perception of body image (OR 0.58, 95% CI 0.34–0.98; p = 0.045), and between the use of nutritional supplements and conformity with body image (OR 0.43, 95% CI 0.25-0.75; p = 0.003) were observed. In conclusion, to greater disagreement with body image or the presence of an altered perception of it, more likely to consume nutritional supplements. (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Suplementos Nutricionais , Condicionamento Físico Humano , Academias de Ginástica , Estudos Transversais , Imagem Corporal , Autoimagem , Ciências da Nutrição e do Esporte
10.
Healthcare (Basel) ; 10(9)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36141226

RESUMO

Self-sampling methods for HPV testing have been demonstrated to be highly sensitive and specific. The implementation of these methods in settings with a lack of infrastructure or medical attention has been shown to increase the coverage of cervical cancer screening and detect cervical abnormalities in the early stages. The aim of this study is to compare the acceptability of urine and vaginal self-sampling methods versus clinician sampling among rural women. A total of 120 women participated. Each participant self-collected urine and vaginal samples and underwent clinician sampling for Pap smear and HPV testing. After the sample collection, a questionnaire to qualify the device, technique, and individual acceptability was applied, and the additional overall preference of three sample tests was evaluated. Results: The characteristics of the participants were as follows: median age of 35 years; 40.8% were married; 46.7% had a primary level of education; median age of sexual onset of 17.6 years. Compared with clinician sampling, both vaginal self-sampling, OR 20.12 (7.67-52.8), and urine sampling, OR 16.63 (6.79-40.72), were more comfortable; granted more privacy: vaginal self-sampling, OR 8.07 (3.44-18.93), and urine sampling, OR 19.5 (5.83-65.21); were less painful: vaginal self-sampling, OR 0.07 (0.03-0.16), and urine sampling, OR 0.01 (0-0.06); were less difficult to apply: vaginal self-sampling, OR 0.16 (0.07-0.34), and urine sampling, OR 0.05 (0.01-0.17). The overall preference has shown an advantage for vaginal self-sampling, OR 4.97 (2.71-9.12). No statistically significant preference was demonstrated with urine self-sampling versus clinician sampling. Conclusions: Self-sampling methods have a high acceptance in rural communities. Doubts on the reliability of self-sampling often appear to be a limitation on its acceptability. However, the training and education of the community could increase the uptake of these methods.

11.
Rev. otorrinolaringol. cir. cabeza cuello ; 82(3): 366-370, sept. 2022. ilus
Artigo em Espanhol | LILACS | ID: biblio-1409948

RESUMO

Resumen El quiste epidérmico es una lesión benigna y común de la piel. Se desarrolla por un bloqueo de la unidad pilosebácea, con la consecuente proliferación de células epiteliales y secuestro de queratina. El 7% se desarrollan en cabeza y cuello, sin embargo, son infrecuentes en canal auditivo externo. Su patrón de crecimiento es lento y progresivo durante años, siendo asintomáticos. Al aumentar de tamaño causan sintomatología variable, acorde a su localización; en el canal auditivo tienen un comportamiento obstructivo que genera síntomas como otalgia e hipoacusia. Se presenta caso de una paciente de 69 años, con acúfeno e hipoacusia progresiva derecha. Durante la otoscopia se observó una neoformación obstructiva del 100% de la luz del conducto. Se realizaron estudios de imagen que reportaron tumoración de características quísticas de conducto auditivo derecho, bien circunscrita, sin erosión ósea. Para el diagnóstico definitivo, se realizó resección quirúrgica y biopsia reportando quiste epidérmico. Durante el seguimiento posoperatorio sin hallazgos de recidiva.


Abstract The epidermal cyst is a common and benign lesion of the skin. It develops due to a blockage of the pilosebaceous unit, with the consequent proliferation of epithelial cells and keratin sequestration. Seven percent develop in the head and neck; however, they are infrequent in the external auditory canal. Its growth pattern is slow and progressive over the years, being asymptomatic. As they increase in size, they cause variable symptoms, according to their location. In the ear canal they have an obstructive behavior that generates symptoms such as earache and hearing loss. A case of a 69-year-old female with tinnitus and progressive right hearing loss is presented. At otoscopy, a 100% obstructive neoformation of the canal lumen was observed. Imaging studies showed a well circumscribed, cystic tumor of the right ear canal, without bone erosion. For the definitive diagnosis, a resection and biopsy were performed, reporting an epidermal cyst. During follow up there was no recurrence of tumor.


Assuntos
Humanos , Feminino , Idoso , Meato Acústico Externo/diagnóstico por imagem , Otopatias/diagnóstico por imagem , Cisto Epidérmico/diagnóstico por imagem , Neoplasias da Orelha/diagnóstico por imagem , Meato Acústico Externo/cirurgia , Otopatias/cirurgia , Otopatias/patologia , Cisto Epidérmico/cirurgia , Cisto Epidérmico/patologia
12.
Rev. esp. med. nucl. imagen mol. (Ed. impr.) ; 41(4): 215-222, jul. - ago. 2022. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-205183

RESUMO

Introducción y objetivos: El volumen metabólico tumoral (VMT) y la glicólisis total de la lesión (TLG) son predictores pronósticos en los pacientes con linfoma B difuso de células grandes (LBDCG). El objetivo del presente estudio es evaluar el impacto pronóstico de los parámetros volumétricos basales calculados con la tomografía por emisión de positrones/tomografía computarizada con 18F-fluorodesoxiglucosa (18F-FDG PET/TC) y su valor agregado a las características moleculares en pacientes con LBDCG tipo no especificado (NOS). Metodología: Se trata de un estudio retrospectivo observacional, en el que se incluyeron 35 pacientes sometidos a un 18F-FDG PET/TC basal previo al tratamiento. Se realizó un análisis univariable de los parámetros volumétricos (VMT y TLG), estudio inmunohistoquímico y traslocaciones cromosómicas. El método para el cálculo de los parámetros volumétricos fue el umbral SUV 2,5. La comparación entre los modelos predictivos se seleccionó en función del valor de criterio de información de Akaike (AIC), bayesiano (BIC) y C de Harrell, después de realizar un modelo de regresión de riesgos proporcionales de Cox. Además, se realizó un análisis univariable de los parámetros volumétricos, según los datos del estudio inmunohistoquímico utilizando la prueba de Wilcoxon-Mann-Whitney. Resultados: Al realizar un análisis univariable se evidenció que el VMT y la TLG son predictores de la supervivencia libre de progresión (SLP) y de la supervivencia global (SG), con una alta capacidad de discriminación. El añadir el VMT y la TLG al estudio inmunohistoquímico y a la traslocación cromosómica proporcionó un mejor valor pronóstico a la SLP y SG en los pacientes diagnosticados con LBDCG tipo NOS. Así mismo, se evidenció que los valores de los parámetros volumétricos eran menores en los pacientes que presentaron un fenotipo células B centro germinal (GCB) frente a los pacientes con fenotipo células B activadas (ABC) que presentaron valores mayores (AU)


Introduction and objectives: Metabolic tumor volume (MTV) and total lesion glycolysis (TLG) are prognostic predictors in patients with diffuse large B-cell lymphoma (DLBCL). The objective of this study is to evaluate the prognostic impact of the baseline volumetric parameters calculated with positron emission tomography/computed tomography with 18F-fluorodeoxyglucose (18F-FDG PET/CT) and its added value to the molecular characteristics in patients with DLBCL not otherwise specified (NOS). Methodology: This is a retrospective observational study, which included 35 patients who underwent a baseline 18F-FDG PET/CT prior to treatment. A univariate analysis of the volumetric parameters (MTV and TLG), immunohistochemical study and chromosomal translocations were performed. The method for calculating the volumetric parameters was the SUV 2.5 threshold. The comparison between the predictive models was selected based on the information criterion value of Akaike (AIC), bayesian (BIC) and Harrell's C, after performing a Cox proportional hazards regression model. In addition, a univariate analysis of the volumetric parameters was performed according to the data of the immunohistochemical study using the Wilcoxon-Mann-Whitney test. Results: A univariate analysis revealed that VMT and TLG are predictors of progression-free survival (PFS) and overall survival (OS), with a high discrimination capacity. Adding VMT and TLG to the immunohistochemical study and chromosomal translocation provided a better prognostic value for PFS and OS in patients diagnosed with DLBCL-NOS. Likewise, it was evidenced that the values of the volumetric parameters were lower in patients who presented a germinal center B cell phenotype (GCB) compared to patients with an activated B cell phenotype (ABC) who presented higher values. Conclusion: MTV and TLG added to the immunohistochemical study and chromosomal translocation provided a better prognostic value for PFS and OS (AU)


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Fluordesoxiglucose F18 , Compostos Radiofarmacêuticos , Linfoma Difuso de Grandes Células B/diagnóstico por imagem , Estudos Retrospectivos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Teorema de Bayes , Prognóstico , Translocação Genética , Imuno-Histoquímica
13.
Fungal Biol ; 126(5): 385-394, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35501034

RESUMO

Endophytic fungi are capable of producing a great diversity of bioactive metabolites. However, the presence of silent and lowly expressed genes represents a main challenge for the discovery of novel secondary metabolites with different potential uses. Epigenetic modifiers have shown to perturb the production of fungal metabolites through the induction of silent biosynthetic pathways leading to an enhanced chemical diversity. Moreover, the addition of bioprecursors to the culture medium has been described as a useful strategy to induce specific biosynthetic pathways. The aim of this study was to assess the effects of different chemical modulators on the metabolic profiles of an endophytic fungal strain of Cophinforma mamane (Botryosphaeriaceae), known to produce 3 thiodiketopiperazine (TDKP) alkaloids (botryosulfuranols A-C), previously isolated and characterized by our team. Four epigenetic modifiers, 5-azacytidine (AZA), sodium butyrate (SB), nicotinamide (NIC), homoserine lactone (HSL) as well as 2 amino acids, l-phenylalanine and l-tryptophan, as bioprecursors of TDKPs, were used. The metabolic profiles were analysed by UHPLC-HRMS/MS under an untargeted metabolomics approach. Our results show that the addition of the two amino acids in C. mamane culture and the treatment with AZA significantly reduced the production of the TDKPs botryosulfuranols A, B and C. Interestingly, the treatment with HSL significantly induced the production of different classes of diketopiperazines (DKPs). The treatment with AZA resulted as the most effective epigenetic modifier for the alteration of the secondary metabolite profile of C. mamane by promoting the expression of cryptic genes.


Assuntos
Aminoácidos , Ascomicetos , Aminoácidos/metabolismo , Ascomicetos/metabolismo , Azacitidina/metabolismo , Azacitidina/farmacologia , Epigênese Genética
15.
Artigo em Inglês | MEDLINE | ID: mdl-35469793

RESUMO

INTRODUCTION AND OBJECTIVES: Metabolic tumor volume (MTV) and total lesion glycolysis (TLG) are prognostic predictors in patients with diffuse large B-cell lymphoma (DLBCL). The objective of this study is to evaluate the prognostic impact of the baseline volumetric parameters calculated with positron emission tomography/computed tomography with 18F-fluorodeoxyglucose (18F-FDG PET/CT) and its added value to the molecular characteristics in patients with DLBCL not otherwise specified (NOS). METHODOLOGY: This is a retrospective observational study, which included 35 patients who underwent a baseline 18F-FDG PET/CT prior to treatment. A univariate analysis of the volumetric parameters (MTV and TLG), immunohistochemical study and chromosomal translocations were performed. The method for calculating the volumetric parameters was the SUV 2.5 threshold. The comparison between the predictive models was selected based on the information criterion value of Akaike (AIC), bayesian (BIC) and Harrell's C, after performing a Cox proportional hazards regression model. In addition, a univariate analysis of the volumetric parameters was performed according to the data of the immunohistochemical study using the Wilcoxon-Mann-Whitney test. RESULTS: A univariate analysis revealed that VMT and TLG are predictors of progression-free survival (PFS) and overall survival (OS), with a high discrimination capacity. Adding VMT and TLG to the immunohistochemical study and chromosomal translocation provided a better prognostic value for PFS and OS in patients diagnosed with DLBCL-NOS. Likewise, it was evidenced that the values of the volumetric parameters were lower in patients who presented a germinal center B cell phenotype (GCB) compared to patients with an activated B cell phenotype (ABC) who presented higher values. CONCLUSION: MTV and TLG added to the immunohistochemical study and chromosomal translocation provided a better prognostic value for PFS and OS in patients diagnosed with DLBCL-NOS.


Assuntos
Fluordesoxiglucose F18 , Linfoma Difuso de Grandes Células B , Teorema de Bayes , Humanos , Linfoma Difuso de Grandes Células B/diagnóstico por imagem , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Prognóstico , Compostos Radiofarmacêuticos , Translocação Genética
18.
Radiologia (Engl Ed) ; 63(6): 505-511, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34801183

RESUMO

The middle cerebral artery (MCA) is one of the principal intracranial vessels. It is also the one that is most often involved in ischemic cerebrovascular disease, which accounts for a significant volume of brain imaging tests. With recent updates in the management of ischemic stroke (including intravascular treatment in increasingly distal vessels and in an increasingly widening spectrum of patients), it is becoming more important to know the details of the cerebral vascular anatomy to reach accurate diagnoses quickly and thereby improve patients' prognoses. For these reasons, we present this anatomic review of the MCA, reviewing its segments and anatomic limits, its branching patterns, and its anatomic variants. We also provide a radiologic tool based on correlations between CT angiography and perfusion CT to facilitate the identification of the points of occlusion within the branches of the MCA, taking into account its different variants.


Assuntos
Angiografia por Tomografia Computadorizada , Artéria Cerebral Média , Humanos , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/diagnóstico por imagem , Perfusão , Trombectomia , Tomografia Computadorizada por Raios X
19.
Radiologia (Engl Ed) ; 2021 Sep 03.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-34489106

RESUMO

The middle cerebral artery (MCA) is one of the principal intracranial vessels. It is also the one that is most often involved in ischemic cerebrovascular disease, which accounts for a significant volume of brain imaging tests. With recent updates in the management of ischemic stroke (including intravascular treatment in increasingly distal vessels and in an increasingly widening spectrum of patients), it is becoming more important to know the details of the cerebral vascular anatomy to reach accurate diagnoses quickly and thereby improve patients' prognoses. For these reasons, we present this anatomic review of the MCA, reviewing its segments and anatomic limits, its branching patterns, and its anatomic variants. We also provide a radiologic tool based on correlations between CT angiography and perfusion CT to facilitate the identification of the points of occlusion within the branches of the MCA, taking into account its different variants.

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