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1.
J Biol Chem ; 297(3): 100988, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34298020

RESUMEN

Nemo-like kinase (NLK) is a member of the mitogen-activated protein kinase family of kinases and shares a highly conserved kinase domain with other mitogen-activated protein kinase family members. The activation of NLK contributes to the pathogenesis of Diamond-Blackfan anemia (DBA), reducing c-myb expression and mechanistic target of rapamycin activity, and is therefore a potential therapeutic target. Unlike other anemias, the hematopoietic effects of DBA are largely restricted to the erythroid lineage. Mutations in ribosomal genes induce ribosomal insufficiency and reduced protein translation, dramatically impacting early erythropoiesis in the bone marrow of patients with DBA. We sought to identify compounds that suppress NLK and increases erythropoiesis in ribosomal insufficiency. We report that the active component of ginseng, ginsenoside Rb1, suppresses NLK expression and improves erythropoiesis in in vitro models of DBA. Ginsenoside Rb1-mediated suppression of NLK occurs through the upregulation of miR-208, which binds to the 3'-UTR of NLK mRNA and targets it for degradation. We also compare ginsenoside Rb1-mediated upregulation of miR-208 with metformin-mediated upregulation of miR-26. We conclude that targeting NLK expression through miRNA binding of the unique 3'-UTR is a viable alternative to the challenges of developing small-molecule inhibitors to target the highly conserved kinase domain of this specific kinase.


Asunto(s)
Anemia de Diamond-Blackfan/patología , Eritropoyesis/efectos de los fármacos , Ginsenósidos/farmacología , Panax/química , Proteínas Serina-Treonina Quinasas/efectos de los fármacos , Regiones no Traducidas 3' , Animales , Humanos
2.
Chem Res Toxicol ; 30(7): 1508-1514, 2017 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-28636814

RESUMEN

Exposure to arsenic is a worldwide problem that affects more than 200 million people. The underlying mechanisms of arsenic toxicity have been difficult to ascertain due to arsenic's pleotropic effects. A number of recent investigations have shown that arsenic can compromise protein quality control through the ubiquitin proteasome system (UPS) or the endoplasmic reticulum associated protein degradation (ERAD) pathway. In this article, a link between arsenic and protein quality control is reported. Biochemical and cellular data demonstrate a misregulation of the ATPase cycle of the ATPase associated with various cellular activities (AAA+) chaperone, p97. Interestingly, the loss of p97 activity is due to the increased rate of ATP hydrolysis, which mimics a collection of pathogenic genetic p97 lesions. Cellular studies, using a well characterized reporter of both the proteasome and p97, show the proteasome to also be compromised. This loss of both p97 and proteasome functions can explain the catastrophic protein quality control issues observed in acute, high level arsenic exposures.


Asunto(s)
Adenosina Trifosfatasas/antagonistas & inhibidores , Arsénico/toxicidad , Complejo de la Endopetidasa Proteasomal/metabolismo , Adenosina Trifosfatasas/metabolismo , Animales , Células Cultivadas , Hidrólisis , Ratones , Células 3T3 NIH
3.
Polymers (Basel) ; 13(19)2021 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-34641112

RESUMEN

Silica nanoparticles (G-SiNPs) blocked with 3-glycidoxypropyl trimethoxysilane (GPTS) were newly applied to hydrogel films for improving film coating properties and to distribute the epoxy groups on the film surface. The effects of the content of epoxy-functionalized G-SiNPs on the crosslinking features by photo-induced radical polymerization and the surface mechanical properties of the hydrogel films containing poly(ethylene glycol) dimethacrylate (PEGDMA) and glycidyl methacrylate (GMA) were investigated. The real-time elastic modulus of various PEG hydrogel mixtures with prepared particles was monitored using a rotational rheometer. The distribution of epoxy groups on the crosslinked film surface was directly and indirectly estimated by the elemental analysis of Si and Br. The surface mechanical properties of various hydrogel films were measured by nano-indentation and nano-scratch tests. The relationship between the rheological and surface properties of PEG-based hydrogel films suggests that the use of small amounts of G-SiNPs enhances the surface hardness and crosslinked network of the film and uniformly distributes sufficient epoxy groups on the film surface for further coating applications.

4.
Materials (Basel) ; 13(15)2020 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-32759811

RESUMEN

Particle motion and coffee ring patterns in water-borne suspensions of polystyrene (PS) particle added with small amounts of secondary hydrophobic decalin are investigated during the drying of the suspension droplets, mainly employing light scattering methods. Very tiny secondary fluid insertions via high-speed agitation effectively link the particles through hydrophobic dissolution leading to the formation of multimodal particulate clusters, with resistance to the outward capillary flow and suppression of coffee ring formation after drying. The impact of decalin on particles is corroborated by actual images acquired from an optical profiler and a scanning electron microscope (SEM). The average particle motion inside the suspension changed by decalin was expressed in terms of mean square displacement (MSD) based on diffusing wave spectroscopy (DWS). Employing multispeckle diffusing wave spectroscopy (MSDWS), the rapid motion or ß-relaxation of particles in various suspensions with and without decalin is quantified in early lag time during the drying of droplets. The change in particle dynamics during suspension drop drying, when adding a small secondary fluid, plays a key role in tuning coffee ring patterns.

5.
Polymers (Basel) ; 11(9)2019 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-31547408

RESUMEN

In this work, the amine-epoxy "click" reaction is shown to be a valuable general tool in the synthesis of reactive hydrogels. The practicality of this reaction arises due to its catalyst-free nature, its operation in water, and commercial availability of a large variety of amine and epoxide molecules that can serve as hydrophilic network precursors. Therefore, hydrogels can be prepared in a modular fashion through a simple mixing of the precursors in water and used as produced (without requiring any post-synthesis purification step). The gelation behavior and final hydrogel properties depend upon the molecular weight of the precursors and can be changed as per the requirement. A post-synthesis modification through alkylation at the nitrogen atom of the newly formed ß-hydroxyl amine linkages allows for functionalizing the hydrogels. For example, ring-opening reaction of cyclic sulfonic ester gives rise to surfaces with a zwitterionic character. Finally, the established gelation chemistry can be combined with soft lithography techniques such as micromolding in capillaries (MIMIC) to obtain hydrogel microstructures.

6.
J Integr Bioinform ; 6(1): 108, 2009 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-20134074

RESUMEN

Despite the large number of software tools developed to address different areas of microarray data analysis, very few offer an all-in-one solution with little learning curve. For microarray core labs, there are even fewer software packages available to help with their routine but critical tasks, such as data quality control (QC) and inventory management. We have developed a simple-to-use web portal to allow bench biologists to analyze and query complicated microarray data and related biological pathways without prior training. Both experiment-based and gene-based analysis can be easily performed, even for the first-time user, through the intuitive multi-layer design and interactive graphic links. While being friendly to inexperienced users, most parameters in Goober can be easily adjusted via drop-down menus to allow advanced users to tailor their needs and perform more complicated analysis. Moreover, we have integrated graphic pathway analysis into the website to help users examine microarray data within the relevant biological content. Goober also contains features that cover most of the common tasks in microarray core labs, such as real time array QC, data loading, array usage and inventory tracking. Overall, Goober is a complete microarray solution to help biologists instantly discover valuable information from a microarray experiment and enhance the quality and productivity of microarray core labs. The whole package is freely available at http://sourceforge.net/projects/goober. A demo web server is available at http://www.goober-array.org.


Asunto(s)
Biología Computacional/métodos , Sistemas de Administración de Bases de Datos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Programas Informáticos , Algoritmos , Perfilación de la Expresión Génica/métodos , Interfaz Usuario-Computador
7.
AMIA Annu Symp Proc ; : 935, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17238554

RESUMEN

Documentation computer tools for nursing homes are uncommon, with few nursing homes having access to electronic systems. At St. Paul's Nursing Home an UCSD student engineering team created a web based solution for the nursing staff progress notes. The purpose was to develop innovative design processes so other groups can emulate similar processes. By collecting information from nurse notes and feedback, a web based system with high level of user input standardization was created. The system is currently in use at the St. Paul's facility.


Asunto(s)
Sistemas de Registros Médicos Computarizados , Registros de Enfermería , Internet
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