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1.
Clin Oncol (R Coll Radiol) ; 35(5): e312-e318, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36804153

RESUMEN

AIMS: Intrahepatic cholangiocarcinoma (iCCA) and hepatocellular carcinoma (HCC) differ in prognosis and treatment. We aimed to non-invasively differentiate iCCA and HCC by means of radiomics extracted from contrast-enhanced standard-of-care computed tomography (CT). MATERIALS AND METHODS: In total, 94 patients (male, n = 68, mean age 63.3 ± 12.4 years) with histologically confirmed iCCA (n = 47) or HCC (n = 47) who underwent contrast-enhanced abdominal CT between August 2014 and November 2021 were retrospectively included. The enhancing tumour border was manually segmented in a clinically feasible way by defining three three-dimensional volumes of interest per tumour. Radiomics features were extracted. Intraclass correlation analysis and Pearson metrics were used to stratify robust and non-redundant features with further feature reduction by LASSO (least absolute shrinkage and selection operator). Independent training and testing datasets were used to build four different machine learning models. Performance metrics and feature importance values were computed to increase the models' interpretability. RESULTS: The patient population was split into 65 patients for training (iCCA, n = 32) and 29 patients for testing (iCCA, n = 15). A final combined feature set of three radiomics features and the clinical features age and sex revealed a top test model performance of receiver operating characteristic (ROC) area under the curve (AUC) = 0.82 (95% confidence interval =0.66-0.98; train ROC AUC = 0.82) using a logistic regression classifier. The model was well calibrated, and the Youden J Index suggested an optimal cut-off of 0.501 to discriminate between iCCA and HCC with a sensitivity of 0.733 and a specificity of 0.857. CONCLUSIONS: Radiomics-based imaging biomarkers can potentially help to non-invasively discriminate between iCCA and HCC.


Asunto(s)
Neoplasias de los Conductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Neoplasias Hepáticas , Humanos , Masculino , Persona de Mediana Edad , Anciano , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/patología , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Colangiocarcinoma/diagnóstico por imagen , Neoplasias de los Conductos Biliares/diagnóstico por imagen , Conductos Biliares Intrahepáticos/diagnóstico por imagen , Conductos Biliares Intrahepáticos/patología
2.
Trials ; 21(1): 180, 2020 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-32054510

RESUMEN

BACKGROUND: This study is a part of a series of two clinical trials. We consider diabetic polyneuropathy (DPN), a common chronic and progressive complication of diabetes mellitus that has several impacts on individuals' foot health and quality of life. Based on the current trends of self-monitoring and self-care, providing a tool with foot-related exercises and educational care may help patients to avoid or reduce the musculoskeletal complications resulting from DPN, improving autonomous performance in daily living tasks. The aim of this trial is to evaluate the effects of an educational booklet for foot care and foot muscle strengthening on DPN symptoms and severity, clinical outcomes, and gait biomechanics in patients with DPN. METHODS/DESIGN: The FOotCAre (FOCA) trial II study has been designed as a single-blind, two-parallel-arm randomized controlled trial. It will include 48 patients with DPN who will be randomly allocated to a control (recommended foot care by international consensus with no foot exercises) group or an intervention (foot-related exercises using an educational booklet three times/week at home for 8 weeks) group. Participants from both groups will be assessed at baseline, after 8 weeks, and at 16 weeks for follow-up. The primary outcomes are the DPN symptoms and severity, and the secondary outcomes are foot-ankle kinematics, gait kinetics, plantar pressure distribution during gait, tactile and vibratory sensitivities, foot strength, functional balance, and foot health and functionality. DISCUSSION: The booklet is a management tool that allows users to be autonomous in their treatment by choosing how and where to perform the exercises. This allows the patients to perform the exercises regularly as a continuous habit for foot care and health, which is an important element in the management of the diabetic foot. As the booklet focuses on specific foot-ankle exercises, we expect that it will improve the clinical aspects of DPN and produce beneficial biomechanical changes during gait, becoming a powerful self-management tool that can be easily implemented to improve the performance of daily living tasks. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04008745. Registered on 2 July 2019.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Neuropatías Diabéticas/rehabilitación , Pie/fisiopatología , Educación del Paciente como Asunto/métodos , Autocuidado/métodos , Actividades Cotidianas , Adolescente , Adulto , Anciano , Neuropatías Diabéticas/diagnóstico , Neuropatías Diabéticas/etiología , Neuropatías Diabéticas/fisiopatología , Ejercicio Físico/fisiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Fuerza Muscular/fisiología , Músculo Esquelético/fisiopatología , Folletos , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Índice de Severidad de la Enfermedad , Método Simple Ciego , Resultado del Tratamiento , Adulto Joven
3.
Faraday Discuss ; 208(0): 269-286, 2018 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-29808836

RESUMEN

In this study, we investigated hollow AgAu nanoparticles with the goal of improving our understanding of the composition-dependent catalytic activity of these nanoparticles. AgAu nanoparticles were synthesized via the galvanic replacement method with controlled size and nanoparticle compositions. We studied extinction spectra with UV-Vis spectroscopy and simulations based on Mie theory and the boundary element method, and ultrafast spectroscopy measurements to characterize decay constants and the overall energy transfer dynamics as a function of AgAu composition. Electron-phonon coupling times for each composition were obtained from pump-power dependent pump-probe transients. These spectroscopic studies showed how nanoscale surface segregation, hollow interiors and porosity affect the surface plasmon resonance wavelength and fundamental electron-phonon coupling times. Analysis of the spectroscopic data was used to correlate electron-phonon coupling times to AgAu composition, and thus to surface segregation and catalytic activity. We have performed all-atom molecular dynamics simulations of model hollow AgAu core-shell nanoparticles to characterize nanoparticle stability and equilibrium structures, besides providing atomic level views of nanoparticle surface segregation. Overall, the basic atomistic and electron-lattice dynamics of core-shell AgAu nanoparticles characterized here thus aid the mechanistic understanding and performance optimization of AgAu nanoparticle catalysts.

4.
Braz J Med Biol Res ; 51(5): e6773, 2018 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-29590259

RESUMEN

Bacterial infections occur worldwide and are a major public health problem. Among pathogens, Staphylococcus aureus is the main causative agent of bacterial diseases in the world. This study aimed to evaluate which components of the immune system could act protectively against a S. aureus infection in intradermally immunized mice. C57BL/6 and A/j mice were immunized intradermally with S. aureus inactivated by heat and then challenged with viable strains in an air pouch model. At 6, 12, and 24 h after the challenge, euthanasia was performed, and the cellular profile of the inflammatory infiltrate, cytokines, and the bacterial load were evaluated in the air pouch lavages. Immunized mice demonstrated that the intradermal immunization with S. aureus promoted protection in C57BL/6 mice by reducing the bacterial, which was correlated with increased serum concentration of IgG antibodies (IgG1 and IgG2a) against S. aureus. The increase in IgG2a antibody levels was correlated with a decrease of bacterial load in intradermally immunized C57BL/6 mice, along with production of IL-17A at the inflammation site, as well as IgG1consumption. Similar results were not found in the A/j lineage. In conclusion, a vaccine against S. aureus should focus more on the individual characteristics of the host because it is a determinant factor for the success of the immunization.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Staphylococcus aureus Resistente a Meticilina/inmunología , Infecciones Estafilocócicas/prevención & control , Vacunas Estafilocócicas/inmunología , Animales , Carga Bacteriana , Citocinas/inmunología , Modelos Animales de Enfermedad , Inmunoglobulina G/inmunología , Ratones , Ratones Endogámicos C57BL , Infecciones Estafilocócicas/inmunología , Vacunas Estafilocócicas/administración & dosificación , Factores de Tiempo
5.
Analyst ; 141(17): 5071-7, 2016 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-27471752

RESUMEN

In this communication, we report one factor that could limit the quantitative analysis by SERS, which has not yet been discussed in the literature. Our results show that SERS experiments performed with the substrate immersed in liquid solutions are subjected to a temporal drift in the Raman signal intensity. Measurements were performed using gold nanoparticle suspensions and gold-covered nanostructured ITO surfaces as SERS substrates, immersed in analyte solutions of crystal violet and 4-mercaptobenzoic acid. Depending on the substrate and the conditions used for measurements, the Raman signal can take between 30 min and several hours to stabilize. This effect, if not taken into account, could have a negative impact on the results of the quantitative chemical analysis by SERS performed in situ in liquid solutions.

6.
Eur Neurol ; 52(4): 198-201, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15539772

RESUMEN

Foreign accent syndrome (FAS), a rare disorder characterized by the emergence of a new accent perceived as foreign by listeners, is usually reported with left brain damage. We here report the case of a 28-year-old native Brazilian who appeared, to the examiner, to show a North American accent during recovery from Broca's aphasia. The lesion was due to a frontal hematoma. Without referring specifically to speech, we asked 10 independent observers to comment on a videotape of the patient's interview. Seven reported that the patient had a foreign accent, while 3 simply noted a 'strange' accent. The observers did not agree on the origin of the accent, 5 identifying it as Spanish, 1 as German, and 1 as south Brazilian. These findings suggest that FAS is not due to the acquisition of a specific foreign accent, but to impairment of the suprasegmental linguistic abilities (tone, accent, pauses, rhythm, and vocal stress) that make it possible to distinguish native language.


Asunto(s)
Hemorragia Cerebral/complicaciones , Lenguaje , Trastornos del Habla/etiología , Conducta Verbal/fisiología , Adulto , Hemorragia Cerebral/patología , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Trastornos del Habla/patología
7.
Regul Pept ; 120(1-3): 167-75, 2004 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-15177935

RESUMEN

In the present paper, the modulation of the basolateral membrane (BLM) Na+ -ATPase activity of inner cortex from pig kidney by angiotensin II (Ang II) and angiotensin-(1-7) (Ang-(1-7)) was evaluated. Ang II and Ang-(1-7) inhibit the Na+ -ATPase activity in a dose-dependent manner (from 10(-11) to 10(-5) M), with maximal effect obtained at 10(-7) M for both peptides. Pharmacological evidences demonstrate that the inhibitory effects of Ang II and Ang-(1-7) are mediated by AT2 receptor: The effect of both polypeptides is completely reversed by 10(-8) M PD 123319, a selective AT2 receptor antagonist, but is not affected by either (10(-12) - 10(-5) M) losartan or (10(-10)-10(-7) M) A779, selective antagonists for AT1 and AT(1-7) receptors, respectively. The following results suggest that a PTX-insensitive, cholera toxin (CTX)-sensitive G protein/adenosine 3',5'-cyclic monophosphate (cAMP)/PKA pathway is involved in this process: (1) the inhibitory effect of both peptides is completely reversed by 10(-9) M guanosine 5'-O-(2-thiodiphosphate) (GDPbetaS; an inhibitor of the G protein activity), and mimicked by 10(-10) M guanosine 5'-O-(3-thiotriphosphate) (GTPgammaS; an activator of the G protein activity); (2) the effects of both peptides are mimicked by CTX but are not affected by PTX; (3) Western blot analysis reveals the presence of the Gs protein in the isolated basolateral membrane fraction; (4) (10(-10)-10(-6) M) cAMP has a similar and non-additive effect to Ang II and Ang-(1-7); (5) PKA inhibitory peptide abolishes the effects of Ang II and Ang-(1-7); and (6) both angiotensins stimulate PKA activity.


Asunto(s)
Angiotensina II/análogos & derivados , Angiotensina II/farmacología , Angiotensina I/farmacología , Antihipertensivos/farmacología , Corteza Renal/efectos de los fármacos , Fragmentos de Péptidos/farmacología , Receptor de Angiotensina Tipo 2/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Vasoconstrictores/farmacología , Adyuvantes Inmunológicos/farmacología , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Bloqueadores del Receptor Tipo 2 de Angiotensina II , Animales , Toxina del Cólera/farmacología , AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/antagonistas & inhibidores , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Proteínas de Unión al GTP/metabolismo , Guanosina Difosfato/metabolismo , Guanosina Trifosfato/metabolismo , Imidazoles/farmacología , Corteza Renal/metabolismo , Corteza Renal/patología , Losartán/farmacología , Toxina del Pertussis/farmacología , Piridinas/farmacología , Receptor de Angiotensina Tipo 2/agonistas , Porcinos
8.
Regul Pept ; 117(1): 37-41, 2004 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-14687699

RESUMEN

Recently, we demonstrated that bradykinin (BK) counteracts the stimulatory effect of Ang-(1-7) on the Na(+)-ATPase activity from basolateral membrane of the proximal tubule through B2 receptor. In the present paper, the signaling pathway involved in the inhibitory response of the Na(+)-ATPase activity to BK was investigated. The following results indicate that the phospholipase A2 (PLA2)/COX/prostaglandin E (PGE2) pathway is implicated in this process: (1) The inhibitory effect of BK on Ang-(1-7)-stimulated enzyme is abolished in a dose-dependent manner by quinacrine (10(-9)-10(-6)M), a nonspecific PLA2 inhibitor, and by PACOCF3 (10(-7)M), an inhibitor of a Ca(2+)-independent PLA2. However, AACOCF3 (2 x 10(-4) M), an inhibitor of the cytosolic PLA2, does not modify the inhibitory effect of BK. (2) The inhibitory effect of BK on the Ang-(1-7)-stimulated enzyme is reversed by cyclooxygenase (COX) inhibitors diclofenac (10(-12) M) and indomethacin (10(-12) M). (3) PGE2 (10(-12)-10(-5) M) inhibits the Na(+)-ATPase activity in a dose dependent manner. (4)The inhibitory effects of PGE2 and BK on the Na(+)-ATPase activity are not cumulative. (5) PGE2 (10(-12)-10(-8) M) counteracts the stimulatory effect of Ang-(1-7) on the enzyme activity in a dose-dependent manner.


Asunto(s)
Angiotensina I/farmacología , Bradiquinina/metabolismo , Dinoprostona/metabolismo , Túbulos Renales Proximales/efectos de los fármacos , Fragmentos de Péptidos/farmacología , Fosfolipasas A/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Animales , Antagonistas del Receptor de Bradiquinina B2 , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Inhibidores de la Ciclooxigenasa/metabolismo , Diclofenaco/metabolismo , Relación Dosis-Respuesta a Droga , Indometacina/metabolismo , Túbulos Renales Proximales/enzimología , Fosfolipasas A2 , Quinacrina/farmacología , Receptor de Bradiquinina B2/metabolismo , Porcinos
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