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2.
Nat Commun ; 13(1): 904, 2022 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-35173167

RESUMEN

Targeted protein degradation allows targeting undruggable proteins for therapeutic applications as well as eliminating proteins of interest for research purposes. While several degraders that harness the proteasome or the lysosome have been developed, a technology that simultaneously degrades targets and accelerates cellular autophagic flux is still missing. In this study, we develop a general chemical tool and platform technology termed AUTOphagy-TArgeting Chimera (AUTOTAC), which employs bifunctional molecules composed of target-binding ligands linked to autophagy-targeting ligands. AUTOTACs bind the ZZ domain of the otherwise dormant autophagy receptor p62/Sequestosome-1/SQSTM1, which is activated into oligomeric bodies in complex with targets for their sequestration and degradation. We use AUTOTACs to degrade various oncoproteins and degradation-resistant aggregates in neurodegeneration at nanomolar DC50 values in vitro and in vivo. AUTOTAC provides a platform for selective proteolysis in basic research and drug development.


Asunto(s)
Autofagia/fisiología , Lisosomas/metabolismo , Proteínas Oncogénicas/metabolismo , Agregado de Proteínas/fisiología , Proteolisis , Línea Celular Tumoral , Células HeLa , Humanos , Unión Proteica/fisiología , Pliegue de Proteína , Proteostasis/fisiología , Transducción de Señal
3.
Cardiovasc Intervent Radiol ; 40(2): 285-290, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27826787

RESUMEN

PURPOSE: To determine the effect of contrast medium dilution during tracheal balloon dilation on balloon deflation time and visibility using a 3-dimensional (3D) printed airway phantom. MATERIALS AND METHODS: A comparison study to investigate balloon deflation times and image quality was performed using two contrast agents with different viscosities, i.e., iohexol and ioxithalamate, and six contrast dilutions with a 3D printed airway phantom. RESULTS: Compared to 1:0 concentration, 3:1, 2:1, 1:1, 1:2, and 1:3, contrast/saline ratios resulted in a 46% (56.2 s), 59.8% (73.1 s), 74.9% (91.6 s), 81.7% (99.8 s), and 83.5% (102 s) reduction for iohexol, respectively, and a 51.8% (54.7 s), 63.8% (67.6 s), 74.7% (79.2 s), 80.5% (85.3 s), and 82.4% (87.4 s) reduction for ioxithalamate, respectively, in the mean balloon deflation time, although at the expense of decreased balloon opacity (3.5, 6.9, 11.1, 12.4, and 13.9%, for iohexol, respectively, and 3.2, 6, 9.6, 10.8, and 12.4%, for ioxithalamate, respectively). CONCLUSIONS: Use of a lower viscosity contrast agent and higher contrast dilution is considered to be able to reduce balloon deflation times and then simultaneously decrease visualization of balloons. The rapid balloon deflation time is likely to improve the safe performance of interventional procedures.


Asunto(s)
Medios de Contraste , Dilatación/instrumentación , Dilatación/estadística & datos numéricos , Fantasmas de Imagen , Impresión Tridimensional , Estenosis Traqueal/terapia , Dilatación/métodos , Relación Dosis-Respuesta a Droga , Humanos , Yohexol , Ácido Yotalámico/análogos & derivados , Factores de Tiempo , Tráquea
4.
Radiol Med ; 120(12): 1083-93, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25952293

RESUMEN

PURPOSE: To evaluate the diagnostic performance of magnetic resonance imaging-estimated proton density fat fraction (MRI-PDFF) using a free-drawn region-of-interest (ROI) measurement of hepatic fat deposition compared to MR spectroscopy (MRS) as the reference standard. MATERIALS AND METHODS: A total of 156 patients underwent 3T MR imaging with a multi-step adaptive fitting approach, multi-echo volume interpolated breath-hold examination (VIBE) acquisition and single-voxel high-speed T2-corrected multiple-echo (1)H-MR spectroscopy (SVS). Seven ROI measurements were performed in each segment of the fat percentage maps ("segmental-PDFF"). Three ROIs were placed at the same level as the SVS ("VOI-PDFF"). Free-hand-drawn ROIs were placed at three different levels along the entire liver ("free-drawn-PDFF") and separately along the right and left lobes ("free-drawn-PDFF-2"). RESULTS: A strong correlation was found between VOI-PDFF and SVS (r = 0.977). The right lobe had greater fat content than the left lobe (p < 0.001). After image analysis, 54 and 46 patients were classified as having steatosis using SVS and free-drawn-PDFF as a reference standard, respectively. The diagnostic performance of free-drawn-PDFF was significantly different from SVS (p < 0.05). CONCLUSION: Free-drawn-PDFF provides accurate and generalized information regarding hepatic fat deposition. It is a useful method, particularly if fat deposition is heterogeneous, and should be considered as a new reference standard.


Asunto(s)
Grasas/análisis , Hígado/química , Imagen por Resonancia Magnética/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Hígado Graso/diagnóstico , Femenino , Humanos , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Estándares de Referencia
5.
Restor Dent Endod ; 38(2): 85-9, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23741711

RESUMEN

When a patient with a fractured anterior tooth visits the clinic, clinician has to restore the tooth esthetically and quickly. For esthetic resin restoration, clinician can use 'Natural Layering technique' and an index for palatal wall may be needed. In this case report, we introduce pre-restoration index technique on a Class IV defect, in which a temporary filling material is used for easy restoration. Chair-side index fabrication for Class IV restoration is convenient and makes a single-visit treatment possible.

6.
J Endod ; 39(6): 795-800, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23683281

RESUMEN

INTRODUCTION: The purpose of this study was to investigate whether in vitro stimulation of pulp cells leads to increased secretion of matrix metalloproteinases (MMPs) and, if so, to identify which MMPs are affected. METHODS: Cells cultured from dental pulp were stimulated with tumor necrosis factor-α (TNF-α) (10 ng/mL) for 24 hours, and lysates were analyzed with an antibody array (Bio-Rad Laboratories, Hercules, CA). The mRNA and protein levels of MMP-3, -10, and -13 were measured by real-time polymerase chain reaction (real-time PCR), enzyme-linked immunosorbent assay (ELISA), Western blot analysis, and zymography. In addition, tumor necrosis factor receptors in the pulp cells were assayed by flow cytometry. The ELISA and real-time PCR results were analyzed by paired t tests. RESULTS: The expression of MMP-3, -10, and -13 was up-regulated in the pulp cells after 24 hours of stimulation with TNF-α (10 ng/mL) as seen in the antibody array, real-time PCR, and ELISA results, but MMP-10 was not detected by Western blotting or casein zymography. Flow cytometry analysis showed that the majority of the pulp cells expressed tumor necrosis factor receptor 1. CONCLUSIONS: In regions of inflammation, TNF-α may initiate the degradation of dental connective tissue by activating MMP-3 and MMP-13. These proteins may play an important pathologic role in the inflammation of dental pulp.


Asunto(s)
Pulpa Dental/enzimología , Metaloproteinasas de la Matriz/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología , Técnicas de Cultivo de Célula , Células Cultivadas , Pulpa Dental/citología , Pulpa Dental/efectos de los fármacos , Humanos , Metaloproteinasa 10 de la Matriz/análisis , Metaloproteinasa 10 de la Matriz/efectos de los fármacos , Metaloproteinasa 13 de la Matriz/análisis , Metaloproteinasa 13 de la Matriz/efectos de los fármacos , Metaloproteinasa 3 de la Matriz/análisis , Metaloproteinasa 3 de la Matriz/efectos de los fármacos , Metaloproteinasas de la Matriz/análisis , Receptores Tipo I de Factores de Necrosis Tumoral/análisis , Factores de Tiempo , Regulación hacia Arriba
7.
Artículo en Inglés | MEDLINE | ID: mdl-18276547

RESUMEN

This paper investigates the effect of K(1.94)Zn(1.06)Ta(5.19)O(15) (KZT) addition on the sintering behavior and piezoelectric properties in lead free piezoelectric ceramics of (K(0.5)Na(0.5))NbO(3) (KNN). The apparent density of sintered KNN ceramics was increased with KZT addition, and a relative density of above 96.3% was obtained with the doping of over 0.5 mol% KZT. The maximum dielectric and piezoelectric properties of epsilon(T)(3)/epsilon(0) = 590, d(33) = 126 pC/N, k(p) = 0.42, and P(r) = 18 microC/cm(2) were obtained from 0.5 mol% KZT-doped KNN ceramics. A small amount of KZT (about 0.5 mol%) was effective for improving the sintering behavior and piezoelectric properties, but KZT addition exceeding 1.0 mol% was effective only for densification. A small amount of KZT was effective for densification of KNN ceramics by promoting K(5.75)Nb(10.8)O(30) liquid phase formation. However, even though KNN with 1.0 to approximately -2.0 mol% KZT had a relative density of >98.5%, the piezoelectric properties were inferior to those of 0.5 mol% KZT-doped KNN, presumably due to the smaller grain size and excess liquid phase of the KNN ceramics doped with higher amounts of KZT. It is believed that a small amount of KZT could be one of the suitable sintering aids to obtain highly dense KNN based piezoelectric.


Asunto(s)
Acústica/instrumentación , Cerámica/química , Cristalización/métodos , Plomo/química , Titanio/química , Transductores , Circonio/química , Impedancia Eléctrica , Electroquímica/instrumentación , Electroquímica/métodos , Diseño de Equipo , Análisis de Falla de Equipo , Calor , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
8.
J Comput Chem ; 25(2): 169-78, 2004 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-14648616

RESUMEN

The effect of thioamide substitution on the conformational stability of an azaglycine-containing peptide, For-AzaGly-NH2 (1), was investigated for the sake of finding possible applications by using ab initio and DFT methods. As model compounds, For-[psiCSNH]-AzaGly-NH2 (2), For-AzaGly-[psiCSNH]-NH2 (3), and For-[psiCSNH]-AzaGly-[psiCSNH]-NH2 (4) were used. Two-dimensional phi-psi potential energy surfaces (PESs) for 2-4 were calculated at the B3LYP/6-31G*//HF/6-31G* level in gas (epsilon = 1.0) and in water (epsilon = 78.4) by applying the isodensity polarizable continuum model (IPCM) method. On the basis of these PESs, the minimum energy conformations for 2-4 were characterized at the B3LYP level with 6-31G*, 6-311G**, and 6-31+G** basis sets. The remarkable structural effect of thioamide substitution for 2-4 is that beta-strand structure is observed as a global or local minimum. The minima of 2-4 are also compared with those for glycine and thioamide-containing glycine peptides. Our theoretical results demonstrate that compounds 2-4 would be used to design controllable secondary structures.


Asunto(s)
Glicina/análogos & derivados , Glicina/química , Péptidos/química , Tioamidas/química , Enlace de Hidrógeno , Modelos Moleculares , Conformación Molecular , Conformación Proteica , Termodinámica
9.
Oncogene ; 22(26): 4035-46, 2003 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-12821938

RESUMEN

Vitamin D(3) upregulated protein 1 (VDUP1) is a 1,25-dihydroxyvitamin D(3) (1,25(OH)(2)D(3)) upregulated protein, and it is induced by various stresses. In human tumor tissues, VDUP1 expression was downregulated. Upon stimulation by growth-inhibitory signals such as TGF-beta1 and 1,25(OH)(2)D(3), its expression was rapidly upregulated as the cell growth was retarded. The transfection of VDUP1 in tumor cells reduced cell growth. The VDUP1 expression was also increased when the cell-cycle progression was arrested. Transfection of VDUP1 induced cell-cycle arrest at the G0/G1 phase, indicating that VDUP1 possesses a tumor-suppressive activity. In addition, it was found that VDUP1 interacted with promyelocytic leukemia zinc-finger, Fanconi anemia zinc-finger, and histone deacetylase 1, which are known to be transcriptional corepressors. VDUP1 itself suppressed IL-3 receptor and cyclin A2 promoter activity. Taken together, these results suggest that VDUP1 is a novel antitumor gene which forms a transcriptional repressor complex.


Asunto(s)
Calcitriol/metabolismo , Proteínas Portadoras/biosíntesis , Neoplasias/metabolismo , Proteínas Represoras , Tiorredoxinas , Factor de Crecimiento Transformador beta/metabolismo , Regulación hacia Arriba , Células 3T3 , Animales , Northern Blotting , Ciclo Celular , Diferenciación Celular , División Celular , Línea Celular , Ciclina A/metabolismo , Ciclina A2 , Proteínas de Unión al ADN/metabolismo , Progresión de la Enfermedad , Anemia de Fanconi/metabolismo , Citometría de Flujo , Fase G1 , Genes Reporteros , Células HL-60 , Histona Desacetilasa 1 , Histona Desacetilasas/metabolismo , Humanos , Hibridación in Situ , Interleucina-3/metabolismo , Células Jurkat , Factores de Transcripción de Tipo Kruppel , Ratones , Microscopía Fluorescente , Regiones Promotoras Genéticas , Proteína de la Leucemia Promielocítica con Dedos de Zinc , Fase de Descanso del Ciclo Celular , Retroviridae/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Tiempo , Factores de Transcripción/metabolismo , Transcripción Genética , Transfección , Factor de Crecimiento Transformador beta1 , Células Tumorales Cultivadas , Dedos de Zinc
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