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1.
Dalton Trans ; 53(7): 3143-3158, 2024 Feb 13.
Article in English | MEDLINE | ID: mdl-38236157

ABSTRACT

Infiltration of the mesoporous structure of SBA-15 silica as a hard template with phenanthroline complexes of Fe3+ and Co2+ allowed the simultaneous dispersion of nitrogen, iron and cobalt species on the surface of the obtained carbonaceous CMK-3 silica replica, with potential as bifunctional heterogeneous catalysts for the cathodic oxygen reduction and evolution reactions (ORR and OER). The textural properties and mesopore structure depended on the composition of the material. The carbonaceous FeCoNCMK-3 (1/1), obtained with an Fe/Co molar ratio of 1/1, exhibited an ordered cylindrical mesoporous structure with a high mesopore volume, a rather homogeneous composition in terms of total and surface concentrations of iron and cobalt, and a balanced presence of pyridinic-, pyrrolic- and graphitic-N species. FeCoNCMK-3 (1/1) could improve the ORR kinetics by adsorption and reduction of O2 through the 4-electron mechanism with a current density of -17.37 mA cm-2, Eonset of 1.13 V vs. RHE and E1/2 of 0.75 V when compared to metal-free, monometallic or bimetallic electrocatalysts with a higher amount of cobalt than that of iron. In addition, FeCoNCMK-3 (1/1) exhibited activity for the OER, presenting lower values of Eonset (1.52 V), Ej10 (1.78 V) and the Tafel slope (76.3 mV dec-1) with respect to other catalysts. When evaluated as a cathode in a prototype of a Zn-air battery, FeCoNCMK-3 (1/1) exhibited a high open circuit voltage of 1.41 V, a peak power density of 66.84 mW cm-2, a large specific capacity of 818.88 mA h gZn-1, and cycling for 20 h but with deactivation upon cycling.

2.
Bio Protoc ; 13(2)2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36789166

ABSTRACT

Single-particle electron cryo-microscopy (cryo-EM) is an effective tool to determine high-resolution structures of macromolecular complexes. Its lower requirements for sample concentration and purity make it an accessible method to determine structures of low-abundant protein complexes, such as those isolated from native sources. While there are many approaches to protein purification for cryo-EM, attaining suitable particle quality and abundance is generally the major bottleneck to the typical single-particle project workflow. Here, we present a protocol using budding yeast ( S. cerevisiae ), in which a tractable immunoprecipitation tag (3xFLAG) is appended at the endogenous locus of a gene of interest (GOI). The modified gene is expressed under its endogenous promoter, and cells are grown and harvested using standard procedures. Our protocol describes the steps in which the tagged proteins and their associated complexes are isolated within three hours of thawing cell lysates, after which the recovered proteins are used directly for cryo-EM specimen preparation. The prioritization of speed maximizes the ability to recover intact, scarce complexes. The protocol is generalizable to soluble yeast proteins that tolerate C-terminal epitope tags. Graphical abstract Overview of lysate-to-grid workflow. Yeast cells are transformed to express a tractable tag on a gene of interest. Following cell culture and lysis, particles of interest are rapidly isolated by co-immunoprecipitation and prepared for cryo-EM imaging (created with BioRender.com).

3.
Med Clin (Engl Ed) ; 160(2): 78-81, 2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36597473

ABSTRACT

Introduction and objectives: To evaluate the diagnostic performance of different artificial intelligence (AI) algorithms for the identification of pulmonary involvement by SARS-CoV-2 based on portable chest radiography (RX). Material and methods: Prospective observational study that included patients admitted for suspected COVID-19 infection in a university hospital between July and November 2020. The reference standard of pulmonary involvement by SARS-CoV-2 comprised a positive PCR test and low-tract respiratory symptoms. Results: 493 patients were included, 140 (28%) with positive PCR and 32 (7%) with SARS-CoV-2 pneumonia. The AI-B algorithm had the best diagnostic performance (areas under the ROC curve AI-B 0.73, vs. AI-A 0.51, vs. AI-C 0.57). Using a detection threshold greater than 55%, AI-B had greater diagnostic performance than the specialist [(area under the curve of 0.68 (95% CI 0.64-0.72), vs. 0.54 (95% CI 0.49-0.59)]. Conclusion: AI algorithms based on portable RX enabled a diagnostic performance comparable to human assessment for the detection of SARS-CoV-2 lung involvement.


Introducción y objetivo: Evaluar el rendimiento diagnóstico de diferentes algoritmos de inteligencia artificial (IA) para la identificación de compromiso pulmonar por SARS-CoV-2 basados en radiografía (Rx) de tórax portátil. Material y método: Estudio observacional prospectivo que incluyó pacientes ingresados por sospecha de infección por COVID-19 en un hospital universitario entre julio y noviembre de 2020. El patrón de referencia de compromiso pulmonar por SARS-CoV-2 comprendió una PCR positiva y síntomas respiratorios bajos. Resultados: Se incluyeron 493 pacientes, 140 (28%) con PCR positiva y 32 (7%) con neumonía por SARS-CoV-2. El algoritmo AI-B tuvo el mejor rendimiento diagnóstico (áreas bajo la curva ROC AI-B 0,73 vs. AI-A 0,51 vs. AI-C 0,57). Utilizando un umbral de detección superior al 55%. AI-B presentó mayor precisión que el especialista (área bajo la curva de 0,68 [IC 95%: 0,64­0,72] vs. 0,54 [IC 95%: 0,49­0,59]). Conclusión: Los algoritmos de IA basados en Rx portátiles permiten una precisión diagnóstica comparable a la humana para la detección de compromiso pulmonar por SARS-CoV-2.

4.
Med. clín (Ed. impr.) ; 160(2): 78-81, enero 2023. ilus
Article in Spanish | IBECS | ID: ibc-214923

ABSTRACT

Introducción y objetivo: Evaluar el rendimiento diagnóstico de diferentes algoritmos de inteligencia artificial (IA) para la identificación de compromiso pulmonar por SARS-CoV-2 basados en radiografía (Rx) de tórax portátil.Material y métodoEstudio observacional prospectivo que incluyó pacientes ingresados por sospecha de infección por COVID-19 en un hospital universitario entre julio y noviembre de 2020. El patrón de referencia de compromiso pulmonar por SARS-CoV-2 comprendió una PCR positiva y síntomas respiratorios bajos.ResultadosSe incluyeron 493 pacientes, 140 (28%) con PCR positiva y 32 (7%) con neumonía por SARS-CoV-2. El algoritmo AI-B tuvo el mejor rendimiento diagnóstico (áreas bajo la curva ROC AI-B 0,73 vs. AI-A 0,51 vs. AI-C 0,57). Utilizando un umbral de detección superior al 55%. AI-B presentó mayor precisión que el especialista (área bajo la curva de 0,68 [IC 95%: 0,64-0,72] vs. 0,54 [IC 95%: 0,49-0,59]).ConclusiónLos algoritmos de IA basados en Rx portátiles permiten una precisión diagnóstica comparable a la humana para la detección de compromiso pulmonar por SARS-CoV-2. (AU)


Introduction and objectives: To evaluate the diagnostic performance of different artificial intelligence (AI) algorithms for the identification of pulmonary involvement by SARS-CoV-2 based on portable chest radiography (RX).Material and methodsProspective observational study that included patients admitted for suspected COVID-19 infection in a university hospital between July and November 2020. The reference standard of pulmonary involvement by SARS-CoV-2 comprised a positive PCR test and low-tract respiratory symptoms.Results493 patients were included, 140 (28%) with positive PCR and 32 (7%) with SARS-CoV-2 pneumonia. The AI-B algorithm had the best diagnostic performance (areas under the ROC curve AI-B 0.73, vs. AI-A 0.51, vs. AI-C 0.57). Using a detection threshold greater than 55%, AI-B had greater diagnostic performance than the specialist [(area under the curve of 0.68 (95% CI 0.64-0.72), vs. 0.54 (95% CI 0.49-0.59)].ConclusionAI algorithms based on portable RX enabled a diagnostic performance comparable to human assessment for the detection of SARS-CoV-2 lung involvement. (AU)


Subject(s)
Humans , Algorithms , Artificial Intelligence , Severe acute respiratory syndrome-related coronavirus , Pneumonia , Radiography , Lung
5.
Med Clin (Barc) ; 160(2): 78-81, 2023 01 20.
Article in English, Spanish | MEDLINE | ID: mdl-35918213

ABSTRACT

INTRODUCTION AND OBJECTIVES: To evaluate the diagnostic performance of different artificial intelligence (AI) algorithms for the identification of pulmonary involvement by SARS-CoV-2 based on portable chest radiography (RX). MATERIAL AND METHODS: Prospective observational study that included patients admitted for suspected COVID-19 infection in a university hospital between July and November 2020. The reference standard of pulmonary involvement by SARS-CoV-2 comprised a positive PCR test and low-tract respiratory symptoms. RESULTS: 493 patients were included, 140 (28%) with positive PCR and 32 (7%) with SARS-CoV-2 pneumonia. The AI-B algorithm had the best diagnostic performance (areas under the ROC curve AI-B 0.73, vs. AI-A 0.51, vs. AI-C 0.57). Using a detection threshold greater than 55%, AI-B had greater diagnostic performance than the specialist [(area under the curve of 0.68 (95% CI 0.64-0.72), vs. 0.54 (95% CI 0.49-0.59)]. CONCLUSION: AI algorithms based on portable RX enabled a diagnostic performance comparable to human assessment for the detection of SARS-CoV-2 lung involvement.


Subject(s)
COVID-19 , Pneumonia , Humans , COVID-19/diagnostic imaging , Artificial Intelligence , SARS-CoV-2 , Radiography , Algorithms , COVID-19 Testing
6.
Rev. bras. oftalmol ; 82: e0063, 2023. graf
Article in English | LILACS | ID: biblio-1529926

ABSTRACT

ABSTRACT Ocular cysticercosis is a parasitic infection caused by Taenia solium. Its early diagnosis and treatment decreases the possibility of visual morbidity. It can either compromise the anterior chamber or the posterior segment, which translates into an very variable and interspecific presentation that changes depending on the site of the infection. It is important to report this case due to its low presentation rate and the fact that a high suspicion index is required to make an assertive and timely diagnosis. This is especially important in geographical areas that are endemic to this parasite due to the direct relationship between an early diagnosis and treatment and better visual outcomes. In this case report, we will discuss the multidisciplinary interventions of a pediatric patient in a high complexity hospital.


RESUMO A cisticercose ocular é uma infecção parasitária causada pela Taenia solium. O diagnóstico e tratamento precoces diminuem a possibilidade de morbidade visual. Ela pode comprometer a câmara anterior ou o segmento posterior, o que se traduz em uma apresentação muito variável e interespecífica, que muda dependendo do local da infecção. É importante relatar esse caso devido à sua baixa taxa de apresentação e ao fato de que é necessário um alto índice de suspeita para fazer um diagnóstico assertivo e oportuno. Isso é especialmente importante em áreas geográficas endêmicas para esse parasita, devido à relação direta entre diagnóstico e tratamento precoces e melhores resultados visuais. Neste relato de caso, discutiremos as intervenções multidisciplinares de um paciente pediátrico em um hospital de alta complexidade.


Subject(s)
Humans , Female , Child, Preschool , Cysticercosis/diagnosis , Eye Infections, Parasitic/diagnosis , Retinoblastoma/diagnosis , Vitrectomy , Vitreous Body/cytology , Magnetic Resonance Imaging , Ultrasonography , Taenia solium , Diagnosis, Differential
7.
Rev. argent. radiol ; 86(2): 83-92, jun. 2022. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1387606

ABSTRACT

Resumen Objetivo: Dar a conocer la experiencia en nuestro departamento de imágenes y presentar los hallazgos de radiografía (Rx) y tomografía computada (TC) que hemos observado en nuestra serie de casos con diagnóstico confirmado de COVID-19. Método: Estudio retrospectivo analítico de los hallazgos de Rx y TC en una serie de pacientes que asistieron al servicio de urgencias por sospecha de COVID-19 en los hospitales universitarios dependientes de nuestra institución en el periodo comprendido entre el 1 de marzo y el 31 de mayo de 2020. Resultados: En el período de estudio se detectaron 127 casos de COVID-19 positivos en nuestra institución. A 57 (45%) de ellos se les realizó Rx. En 46 (80%) de ellas no mostraron hallazgos patológicos. En 8 (14%) pacientes se observaron opacidades parcheadas en vidrio esmerilado y en 3 (5%) en asociación con consolidaciones. La distribución fue predominantemente bilateral y en los lóbulos inferiores. A 11 pacientes se les realizó TC de tórax y 9 (81%) manifestaron infiltrados en vidrio esmerilado, mostrando preferencia por las áreas periféricas y los lóbulos superiores, asociándose a consolidaciones en 4 (36%) casos. Un paciente (9%) presentó patrón en empedrado y otros 2 mostraron opacidades (18%) redondeadas en vidrio esmerilado. Dos pacientes (18%) no tuvieron hallazgos patológicos. Como hallazgos atípicos, se evidenció derrame pleural en 2 pacientes (18%) y neumotórax en uno (9%) en uno de ellos. Conclusiones: Nuestra experiencia demostró como características frecuentes la presencia de opacidades parcheadas en vidrio esmerilado y consolidaciones parcheados de distribución predominantemente en los lóbulos inferiores.


Abstract Objective: To show the experience in our radiology department at X-ray and computed tomography (CT) imaging findings in patients with confirmed COVID-19. Method: Retrospective analytical study of the radiological findings on X-ray and CT on a series of patients who attended the emergency department on suspicion of COVID-19 at university hospitals dependent of our institution in the period between March 1 and May 31, 2020. Results: During the study period, 127 cases of COVID-19 were detected in our institution. X-rays were performed in 57 (45%) of them, 46 (80%) of which did not show pathological findings. In total, 8 (14%)manifested as patchy ground glass opacities, and 3 (5%), in association with consolidations. The distribution was predominantly bilateral and in the lower lobes. Eleven patients underwent chest CT, 9 (81%) of these showed ground glass opacities, showing a preference for peripheral areas and upper lobes, associated with consolidations in 4 (36%) of them. One patient (9%) presented crazy paving and 2 rounded (18%) ground glass opacities. Two patients (18%) showed no pathological findings. As atypical findings, pleural effusion was evident in two (18%) patients, and pneumothorax, in one (9%). Conclusions: Our experience demonstrated the presence of patchy ground glass opacities and patchy consolidative opacities predominantly in the lower lobes as frequent features.

10.
Matrix Biol Plus ; 8: 100046, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33543039

ABSTRACT

The extracellular matrix (ECM) acts as reservoir for a plethora of growth factors and cytokines some of which are hypothesized to be regulated by ECM fiber tension. Yet, ECM fiber tension has never been mapped in healthy versus diseased organs. Using our recently developed tension nanoprobe derived from the bacterial adhesin FnBPA5, which preferentially binds to structurally relaxed fibronectin fibers, we discovered here that fibronectin fibers are kept under high tension in selected healthy mouse organs. In contrast, tumor tissues and virus-infected lymph nodes exhibited a significantly higher content of relaxed or proteolytically cleaved fibronectin fibers. This demonstrates for the first time that the tension of ECM fibers is significantly reduced upon pathological tissue transformations. This has wide implications, as the active stretching of fibronectin fibers adjusts critical cellular niche parameters and thereby tunes the reciprocal cell-ECM crosstalk. Mapping the tensional state of fibronectin fibers opens novel and unexpected diagnostic opportunities.

11.
EMBO Rep ; 15(1): 77-85, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24378640

ABSTRACT

Loss of primary cilia is a key feature of von Hippel-Lindau tumor suppressor (VHL)-associated pathology. Although VHL-deficiency predisposes cells to precipitous cilia disassembly in response to growth factor cues, it does not affect ciliogenesis. Here, using a siRNA-based screen to find genes that are essential for ciliogenesis only in the presence of the VHL tumor suppressor gene product pVHL, we identify ubiquitin-specific protease (USP)8. The pVHL-dependency of USP8 for ciliogenesis is directly linked to its function as a HIF1α deubiquitinating enzyme. By counteracting pVHL-mediated ubiquitination of HIF1α, USP8 maintains a basal expression of HIF1α and HIF transcriptional output in normoxia, including the repression of Rabaptin5, which is essential for endosome trafficking-mediated ciliogenesis.


Subject(s)
Cilia/physiology , Endopeptidases/physiology , Endosomal Sorting Complexes Required for Transport/physiology , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Ubiquitin Thiolesterase/physiology , Ubiquitination , Animals , Cell Hypoxia , Endocytosis , HEK293 Cells , Humans , Mice , Oxygen/metabolism , Protein Binding , Protein Stability , Protein Transport , Vesicular Transport Proteins/metabolism , Von Hippel-Lindau Tumor Suppressor Protein/genetics , Von Hippel-Lindau Tumor Suppressor Protein/metabolism
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