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1.
Heliyon ; 9(11): e21306, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38027584

RESUMEN

Semiconductor development is a major driving force for global economic growth. However, synchronizing it with the Sustainable Development Goals (SDGs) set by the United Nations remains a critical challenge. To gain insight into this, we analyzed SDG-related publications on semiconductors from 2017 to 2022 using the SciVal database. The study found 77,706 documents related to SDGs in the field of semiconductor research, with an overall increase in the number of publications each year. The main focus of these publications was SDG 7 (Affordable and Clean Energy), accounting for 68.9 % of the total publication count. Additionally, the results indicate that semiconductors have multifaceted potential in advancing a range of SDGs. From fostering innovations in healthcare (SDG 3), ensuring clean water access (SDG 6), catalyzing transformative industrial growth (SDG 9), to contributing to climate mitigation strategies (SDG 13), semiconductors emerge as versatile drivers of sustainable development. The respective publication percentages for these goals were 7.3 %, 5.9 %, 9.7 %, and 4.4 %, underscoring their capacity to make substantial contributions across various facets of sustainability. It's worth noting that only 2.9 % of these publications stem from academia-industry collaborations. This indicates a pressing need to facilitate collaboration between academia and industry, as such partnerships have the potential to amplify the impact of semiconductor innovations on the SDGs. The novelty of this study lies in its specific exploration through a comprehensive analysis spanning five years, revealing the alignment between semiconductor advancements and the latest SDGs. It uncovers the significance of collaborative ecosystems involving research institutions, businesses, and governments. Through these results, our study addresses a gap in the existing literature and advances semiconductor contributions to the SDGs.

2.
J Am Coll Health ; : 1-8, 2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36596232

RESUMEN

Objective: This study is an exploration of the major stressors associated with the COVID-19 for students in higher education in Taiwan. Participants: The sample comprised 838 higher education students studying at various Taiwanese universities. Methods: A cross-sectional online survey was administered at different postsecondary institutions during the semi-lockdown period of COVID-19, which mandated online instruction. Machine learning was employed to determine the variables that most highly predicted students' mental health using R. Results: The findings revealed that COVID-19-related experiences, including social interactions, financial conditions, and educational experiences, were significantly associated with mental health outcomes. Particularly, loneliness are significantly related to social interactions and educational experiences. Conclusions: Findings revealed that Covid-19 impacted Taiwanese students' financial conditions, educational experiences, and social interactions, which were significant predictors of their mental health outcomes such as anxiety, loneliness and depression. The current study contributes to the gap in knowledge about mental health issues among postsecondary students during the pandemic.

3.
Psychol Rep ; 126(5): 2489-2510, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35343336

RESUMEN

This study was an investigation of the relationship between past and present learning experiences of first-year college students and of how the psychological capital and academic self-efficacy they had accrued from past learning experiences were correlated with their current learning engagement. Longitudinal data were collected to examine how students' learning experiences in high school impacted their learning in college. Structural equation modeling (SEM) and bootstrapping techniques were employed in data analysis. Results indicated that psychological capital and academic self-efficacy functioned as mediators between students' past learning experience and present learning engagement. Overall, the findings highlight the importance of these two psychological constructs and suggest that postsecondary institutions should provide learning environments that support these factors to ensure student success.


Asunto(s)
Aprendizaje , Autoeficacia , Humanos , Universidades , Estudiantes/psicología , Instituciones Académicas
4.
Cells ; 9(6)2020 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-32570745

RESUMEN

Single-cell cloning (SCC) is a critical step in generating monoclonal cell lines, which are widely used as in vitro models and for producing proteins with high reproducibility for research and the production of therapeutic drugs. In monoclonal cell line generation, the development time can be shortened by validating the monoclonality of the cloned cells. However, the validation process currently requires specialized equipment that is not readily available in general biology laboratories. Here, we report a disposable SCC device, in which single cells can be isolated, validated, and expanded to form monoclonal cell colonies using conventional micropipettes and microscopes. The monoclonal cells can be selectively transferred from the SCC chip to conventional culture plates, using a tissue puncher. Using the device, we demonstrated that monoclonal colonies of actin-GFP (green fluorescent protein) plasmid-transfected A549 cells could be formed in the device within nine days and subsequently transferred to wells in plates for further expansion. This approach offers a cost-effective alternative to the use of specialized equipment for monoclonal cell generation.


Asunto(s)
Técnicas de Cultivo de Célula/instrumentación , Células Clonales/citología , Dispositivos Laboratorio en un Chip , Células A549 , Actinas/genética , Separación Celular , Células Clonales/metabolismo , Dimetilpolisiloxanos , Diseño de Equipo , Citometría de Flujo , Proteínas Fluorescentes Verdes/genética , Humanos , Transfección
5.
Biofabrication ; 11(3): 035024, 2019 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-31051482

RESUMEN

In vitro testing of drug compounds on cell models during the drug development process represents an indispensable step in the initial screening process. Although drug testing on three-dimensional (3D) cultured cells may provide a more accurate prediction of drug efficacy, it is relatively costly and time-consuming to perform compared with conventional 2D cultures due to the thick z-axis of the 3D models. In this study, we have presented a microfluidic platform with integrated pneumatic valves for producing a thin-gel 3D cell culture-based combinatorial drug screening array (3D-µCDS array). The multilayer architecture and microfluidic layout has a smaller device footprint than a single-layer microfluidic channel arrangement, making it well suited to scaling up for high-throughput combinatorial drug screening on 3D cell model. We performed 8 × 8 combination drug screening experiments with the device using two anti-cancer drugs (doxorubicin and paclitaxel) on MDA-MB-231 and MCF-7 breast cancer cell lines for demonstration. Our results indicate that our 3D-µCDS array device allows the successful screening of multiple drug combinations while reducing the operation time and the number of sample/reagents required, making it an ideal tool for general combinatorial drug screening, as well as for applications using valuable tissues and clinical samples.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Técnicas Químicas Combinatorias , Evaluación Preclínica de Medicamentos , Microfluídica/métodos , Animales , Colágeno/farmacología , Difusión , Diseño de Equipo , Matriz Extracelular/química , Fluorescencia , Geles/química , Ensayos Analíticos de Alto Rendimiento , Humanos , Concentración 50 Inhibidora , Microfluídica/instrumentación , Ratas , Células Tumorales Cultivadas
6.
Biosens Bioelectron ; 117: 175-182, 2018 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-29902633

RESUMEN

Here we report an electrochemical immunoassay platform called Proton-ELISA (H-ELISA) for the detection of bioanalytes. H-ELISA uniquely utilizes protons as an immunoassay detection medium, generated by the enzyme glucose oxidase (GOx) coupled with Fenton's reagent in a proton amplification reaction cascade that results in a highly amplified signal. A proton-sensitive dual-gated ion-sensitive field effect transistor (DG-ISFET) sensor was also developed for sensitive and accurate detection of the proton signal in H-ELISA. The DG-ISFET sensor comprises of a 128 × 128 array of 16,384 sensing transistors each with an individually addressable back gate to allow for a very high signal throughput and improved accuracy. We then demonstrated that the platform could detect C-reactive protein and immunoglobulin E down to concentrations of 12.5 and 125 pg/mL, respectively. We further showed that the platform is compatible with complex biological sample conditions such as human serum, suggesting that the platform is sufficiently robust for potential diagnostic applications.


Asunto(s)
Análisis Químico de la Sangre/métodos , Proteína C-Reactiva/análisis , Técnicas Electroquímicas , Ensayo de Inmunoadsorción Enzimática , Inmunoensayo/métodos , Inmunoglobulina E/análisis , Protones , Glucosa Oxidasa/metabolismo , Humanos , Inmunoglobulina E/sangre , Iones/química , Límite de Detección
7.
J Vis Exp ; (112)2016 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-27341146

RESUMEN

Studying the heterogeneity of single cells is crucial for many biological questions, but is technically difficult. Thus, there is a need for a simple, yet high-throughput, method to perform single-cell culture experiments. Here, we report a microfluidic chip-based strategy for high-efficiency single-cell isolation (~77%) and demonstrate its capability of performing long-term single-cell culture (up to 7 d) and cellular heterogeneity analysis using clonogenic assay. These applications were demonstrated with KT98 mouse neural stem cells, and A549 and MDA-MB-435 human cancer cells. High single-cell isolation efficiency and long-term culture capability are achieved by using different sizes of microwells on the top and bottom of the microfluidic channel. The small microwell array is designed for precisely isolating single-cells, and the large microwell array is used for single-cell clonal culture in the microfluidic chip. This microfluidic platform constitutes an attractive approach for single-cell culture applications, due to its flexibility of adjustable cell culture spaces for different culture strategies, without decreasing isolation efficiency.


Asunto(s)
Técnicas Analíticas Microfluídicas , Animales , Técnicas de Cultivo de Célula , Separación Celular , Humanos , Ratones , Microfluídica , Células-Madre Neurales
8.
Methods Mol Biol ; 1516: 289-297, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27044047

RESUMEN

Neurosphere assay is a common and robust method for identification of neural stem/progenitor cells, but obtaining large numbers of live single cells from dissociated neurospheres is difficult using nonenzymatic methods. Here, we present an enzyme-free method for high-efficiency neurosphere dissociation into single cells using microfluidic device technology. This method allows single cell dissociation of DC115 and KT98 cells with high cell viabilities (80-85 %), single-cell yield (91-95 %), and recovery (75-93 %).


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Técnicas Analíticas Microfluídicas/métodos , Microfluídica/métodos , Células-Madre Neurales/citología , Animales , Diferenciación Celular/genética , Ratones
10.
IEEE Trans Nanobioscience ; 14(8): 835-40, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26415207

RESUMEN

In vitro cell motility assays are frequently used in the study of cell migration in response to anti-cancer drug treatment. Microfluidic systems represent a unique tool for the in vitro analysis of cell motility. However, they usually rely on using time-lapse microscopy to record the spatial temporal locations of the individual cells being tested. This has created a bottleneck for microfluidic systems to perform high-throughput experiments due to requirement of a costly time-lapse microscopy system. Here, we describe the development of a portable microfluidic device for endpoint analysis of cell motility. The reported device incorporates a cell alignment feature to position the seeded cells on the same initial location, so that the cells' motilities can be analyzed based on their locations at the end of the experiment after the cells have migrated. We show that the device was able to assess cancer cell motility after treatment with a migration inhibitory drug Indole-3-carbinol on MDA-MB-231 breast cancer cells, demonstrating the applicability of our device in screening anti-cancer drug compounds on cancer cells.


Asunto(s)
Ensayos de Migración Celular/métodos , Técnicas Analíticas Microfluídicas/métodos , Antineoplásicos/farmacología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Diseño de Equipo , Humanos
11.
Lab Chip ; 15(14): 2928-38, 2015 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-26060987

RESUMEN

In vitro culture of single cells facilitates biological studies by deconvoluting complications from cell population heterogeneity. However, there is still a lack of simple yet high-throughput methods to perform single cell culture experiments. In this paper, we report the development and application of a microfluidic device with a dual-well (DW) design concept for high-yield single-cell loading (~77%) in large microwells (285 and 485 µm in diameter) which allowed for cell spreading, proliferation and differentiation. The increased single-cell loading yield is achieved by using sets of small microwells termed "capture-wells" and big microwells termed "culture-wells" according to their utilities for single-cell capture and culture, respectively. This novel device architecture allows the size of the "culture" microwells to be flexibly adjusted without affecting the single-cell loading efficiency making it useful for cell culture applications as demonstrated by our experiments of KT98 mouse neural stem cell differentiation, A549 and MDA-MB-435 cancer cell proliferation, and single-cell colony formation assay with A549 cells in this paper.


Asunto(s)
Ensayos Analíticos de Alto Rendimiento , Técnicas Analíticas Microfluídicas , Células-Madre Neurales/citología , Análisis de la Célula Individual , Animales , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Ensayos Analíticos de Alto Rendimiento/instrumentación , Humanos , Ratones , Técnicas Analíticas Microfluídicas/instrumentación , Análisis de la Célula Individual/instrumentación
12.
Biochim Biophys Acta ; 1853(5): 1174-81, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25728284

RESUMEN

Downregulation of multiple cell cycle-regulatory molecules is a dominant event in TGF-ß1-mediated growth inhibition of human carcinoma cells. It is known that KLF10 mimics the anti-proliferative and apoptotic effects that TGF-ß1 has on epithelial cell growth and the growth of various tumor cells; based on these findings it is considered as a tumor suppressor. KLF10 protein expression is tightly associated with cell cycle-dependent events. However, the regulatory mechanism and its biological meaning have not been identified. In this study, we have demonstrated that KLF10 is a substrate of CDK2/cyclin E and can be phosphorylated. We also have shown that KLF10 efficiently binds to CDK2, while binding much less to CDK4, and displaying no binding to Cdk6. Using mass spectrometry, site direct mutagenesis, in vitro kinase assays and depletion assays, we have established that CDK2 phosphorylates Ser206, which subsequently affects the steady state level of KLF10 in cells. Our studies have also proved that CDK2 up-regulates the protein level of KLF10 through reducing its association with SIAH1, a KLF10 E3-ubiqutin ligase involved in proteasomal degradation. Taken all together, these findings indicate that CDK2-dependent phosphorylation regulates KLF10 stability and that this affects the role of KLF10 in cell.


Asunto(s)
Quinasa 2 Dependiente de la Ciclina/metabolismo , Factores de Transcripción de la Respuesta de Crecimiento Precoz/metabolismo , Factores de Transcripción de Tipo Kruppel/metabolismo , Proteínas Nucleares/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Secuencia de Aminoácidos , Línea Celular Tumoral , Factores de Transcripción de la Respuesta de Crecimiento Precoz/química , Humanos , Factores de Transcripción de Tipo Kruppel/química , Datos de Secuencia Molecular , Fosforilación , Fosfoserina/metabolismo , Unión Proteica , Estabilidad Proteica
13.
Int J Biochem Cell Biol ; 60: 53-9, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25578559

RESUMEN

TGF-ß plays a significant role in regulating pancreas islet function and maintaining their mass. KLF10, a TGF-ß downstream gene, belongs to a group of Krüppel-like transcription factors that bind to the promoters of target genes and produce effects that mimic TGF-ß as a tumor suppressor. Using ChIP-chip screening, SEI-1 was identified as a target gene that may be regulated by KLF10. We conducted a series of assays to verify the presence of unknown regulation events between SEI-1 and KLF10. These showed that KLF10 transcriptionally activates the SEI-1 promoter and, furthermore, induces SEI-1 protein expression in pancreatic carcinoma cells. SEI-1 is one of the key factors involved in cell cycle control through the regulation of other transcription factors such as the p21(Cip1) gene. Interestingly, it has been shown previously that p21(Cip1) is indirectly activated by KLF10. Our results first demonstrated that KLF10 acts as a transcriptional activator on SEI-1, which can then result in increased p21(Cip1) expression. Furthermore, KLF10-deficiency in mice is associated with a decrease in the pancreatic islet mass, which is similar to the effects found in SEI-1 deficient mice. The KLF10-defect was also associated with the nuclear accumulation of the p21(Cip1) in islet cells. Based on our molecular and histological findings, we conclude that KLF10 plays an important role in pancreatic ß-cells and this supports a functional link between KLF10 and various cell cycle regulators, most notably in the context of the pancreas.


Asunto(s)
Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Factores de Transcripción de la Respuesta de Crecimiento Precoz/metabolismo , Factores de Transcripción de Tipo Kruppel/metabolismo , Proteínas Nucleares/metabolismo , Páncreas/metabolismo , Transactivadores/metabolismo , Animales , Western Blotting , Línea Celular Tumoral , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Factores de Transcripción de la Respuesta de Crecimiento Precoz/genética , Ensayo de Cambio de Movilidad Electroforética , Prueba de Tolerancia a la Glucosa , Humanos , Inmunohistoquímica , Factores de Transcripción de Tipo Kruppel/genética , Ratones , Proteínas Nucleares/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transactivadores/genética , Factores de Transcripción
14.
Anal Chem ; 85(24): 11920-8, 2013 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-24228937

RESUMEN

Obtaining single dissociated cells from neurospheres is difficult using nonenzymatic methods. In this paper we report the development of a microfluidic-chip-based approach that utilizes flow and microstructures to dissociate neurospheres. We show that this microfluidic-chip-based neurosphere-dissociation method can generate high yields of single cells from dissociated neurospheres of mouse KT98 and DC115 cell models (passage number, 3-8; diameter range, 40-250 µm): 90% and 95%, respectively. The microfluidic-chip-dissociated cells had high viabilities (80-85%) and the ability to regrow into neurospheres, demonstrating the applicability of this device to neurosphere assay applications. In addition, the dissociated cells retained their normal differentiation potentials, as shown by their capabilities to differentiate into three neural lineages (neurons, astroglia, and oligodendrocytes) when cultured in differentiation culture conditions. Since this microfluidic-chip-based method does not require the use of enzymatic reagents, the risk of contamination from exogenous substances could be reduced, making it an attractive tool for a wide range of applications where neurosphere dissociation is needed.


Asunto(s)
Técnicas Analíticas Microfluídicas/métodos , Células-Madre Neurales/citología , Análisis de la Célula Individual/métodos , Animales , Diferenciación Celular , Línea Celular , Supervivencia Celular , Diseño de Equipo , Ratones , Técnicas Analíticas Microfluídicas/instrumentación , Análisis de la Célula Individual/instrumentación
15.
Biochim Biophys Acta ; 1833(12): 3035-3045, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23994618

RESUMEN

KLF10 is now classified as a member of the Krüppel-like transcription factor family and acts as a tumor suppressor. Although KLF10 is originally named as TGF-ß-inducible early gene-1 and mimicking the anti-proliferative effect of TGF-ß in various carcinoma cells, the transcriptional upregulatory function of KLF10 has been described for a variety of cytokines and in many diseases. Through in vivo and in vitro phosphorylation assays, we identified that KLF10 is a phosphorylated protein in cells. Using yeast-two hybrid screening and site direct mutagenesis, we also identified PIN1 as a novel KLF10 associated protein. PIN1 is a peptidyl-prolyl isomerase enzyme belonging to the parvulin family, which specifically recognizes phosphorylated Ser/Thr-Pro containing substrates. Through protein-protein interaction assays, we showed that the Pro-directed Ser/Thr-Pro motif at Thr-93 in the KLF10 N-terminal region is essential for the interaction between KLF10 and PIN1. More importantly, PIN1 interacts with KLF10 in a phosphorylation-dependent manner and this interaction promotes KLF10 protein degradation in cells. Therefore, KLF10 shows shorter protein stability compared with mutant KLF10 that lacks PIN1 binding ability after cycloheximide treatments. The reversely correlated expression profile between KLF10 and PIN1 as observed in cell lines was also shown in clinic pancreatic cancer specimen. Using in vitro kinase assays and depletion assays, we were able to show that RAF-1 phosphorylates the Thr-93 of KLF10 and affects the KLF10 expression level in cells. Thus these findings as a whole indicate that RAF-1 phosphorylation and PIN1 isomerization together regulate KLF10 stability and further affect the role of KLF10 in tumor progression.


Asunto(s)
Factores de Transcripción de la Respuesta de Crecimiento Precoz/metabolismo , Factores de Transcripción de Tipo Kruppel/metabolismo , Isomerasa de Peptidilprolil/metabolismo , Fosfotreonina/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Secuencias de Aminoácidos , Animales , Línea Celular Tumoral , Factores de Transcripción de la Respuesta de Crecimiento Precoz/química , Humanos , Factores de Transcripción de Tipo Kruppel/química , Ratones , Peptidilprolil Isomerasa de Interacción con NIMA , Fosforilación , Fosfoserina/metabolismo , Unión Proteica , Mapeo de Interacción de Proteínas , Estabilidad Proteica , Proteolisis , Proteínas Proto-Oncogénicas c-raf/metabolismo , Proteínas Supresoras de Tumor/química
16.
J Biomed Opt ; 17(10): 101512, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23223988

RESUMEN

Nanodiamond has been proven to be biocompatible and proposed for various biomedical applications. Recently, nanometer-sized diamonds have been demonstrated as an effective Raman/fluorescence probe for bio-labeling, as well as, for drug delivery. Bio-labeling/drug delivery can be extended to the human blood system, provided one understands the interaction between nanodiamonds and the blood system. Here, the interaction of nanodiamonds (5 and 100 nm) with human red blood cells (RBC) in vitro is discussed. Measurements have been facilitated using Raman spectroscopy, laser scanning fluorescence spectroscopy, and laser diffractometry (ektacytometry). Data on cell viability and hemolytic analysis are also presented. Results indicate that the nanodiamonds in the studied condition do not cause hemolysis, and the cell viability is not affected. Importantly, the oxygenation/deoxygenation process was not found to be altered when nanodiamonds interacted with the RBC. However, the nanodiamond can affect some RBC properties such as deformability and aggregation in a concentration dependent manner. These results suggest that the nanodiamond can be used as an effective bio-labeling and drug delivery tool in ambient conditions, without complicating the blood's physiological conditions. However, controlling the blood properties including deformability of RBCs and rheological properties of blood is necessary during treatment.


Asunto(s)
Deformación Eritrocítica/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Nanodiamantes , Oxígeno/sangre , Supervivencia Celular/efectos de los fármacos , Membrana Eritrocítica/efectos de los fármacos , Eritrocitos/química , Eritrocitos/citología , Hemólisis/efectos de los fármacos , Humanos , Oxígeno/química , Análisis Espectral
17.
Sci Total Environ ; 425: 135-45, 2012 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-22481054

RESUMEN

First measurements of ambient 10-1000 nm particle number concentrations (N(TOT)) and size distributions were made at an urban, coastal, mountain and downwind site within the Central Taiwan Air Quality Management District during a cold and a warm period. The primary objectives were to characterize the spatial and temporal variability of the size-fractionated submicrometer particles and their relationships with copollutants and meteorological parameters. The results show that the ultrafine particles (<100 nm) are the major contributor to the N(TOT). The mean N(TOT) was highest at the urban site, whereas lower and comparable at the three other sites. Although the mean N(TOT) at each site showed insignificant differences between study periods, their diurnal patterns and size distribution modal characteristics were modestly to substantially different between study sites. Correlation analyses of time-resolved collocated aerosol, copollutants and meteorological data suggest that the observed variability is largely attributable to the local traffic and to a lesser extent photochemistry and SO(2) possibly from combustion sources or regional transport. Despite sharing a common traffic source, the ultrafine particles were poorly correlated with the accumulation particles (100-1000 nm), between which the latter showed strong positive correlation with the PM(2.5) and PM(10). Overall, the N(TOT) and size distributions show modest spatial heterogeneity and strong diurnal variability. In addition, the ultrafine particles have variable sources or meteorology-dependent formation processes within the study area. The results imply that single-site measurements of PM(2.5), PM(10) or N(TOT) alone and without discriminating particle sizes would be inadequate for exposure and impact assessment of submicrometer particle numbers in a region of diverse environments.


Asunto(s)
Contaminación del Aire/análisis , Tamaño de la Partícula , Material Particulado/análisis , Aire , Contaminantes Atmosféricos/análisis , Exposición a Riesgos Ambientales , Monitoreo del Ambiente/métodos , Dióxido de Azufre/análisis , Taiwán
18.
Nanomedicine ; 8(5): 609-17, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22033083

RESUMEN

Antibacterial activity of photocatalytic substrates is primarily induced by ultraviolet light irradiation. Visible light-responsive photocatalysts were recently discovered, offering greater opportunity to use photocatalysts as disinfectants in our living environment. The development of antibacterial photocatalysts, however, has mainly focused on titanium oxide (TiO(2))-related materials with antibacterial properties not comparable with conventional chemical disinfectants. This study demonstrated that a core-shell structured In(2)O(3)@CaIn(2)O(4) substrate has superior visible light-induced bactericidal properties, as compared with several commercially available and laboratory-prepared visible light-responsive photocatalysts. The high performance is enhanced by more easily photoexcited electron transfer between the interfaces of In(2)O(3) and CaIn(2)O(4) to minimize the electron-hole recombination during photocatalysis. Additionally, when compared with TiO(2)-based photocatalysts, In(2)O(3)@CaIn(2)O(4) treatments did not induce significant cell death and tissue damage, implying a superior biocompatibility. These findings suggest that In(2)O(3)@CaIn(2)O(4) may have potential application in the development of a safer and highly bactericidal photocatalyst. FROM THE CLINICAL EDITOR: A photocatalytic susbstrate is described that functions in visible light, possesses bactericidal properties and better biocompatibility than the standard TiO(2) based methods.


Asunto(s)
Antibacterianos , Carbonato de Calcio , Desinfectantes , Indio , Nanopartículas/administración & dosificación , Antibacterianos/química , Antibacterianos/farmacología , Carbonato de Calcio/química , Carbonato de Calcio/farmacología , Catálisis/efectos de la radiación , Desinfectantes/química , Desinfectantes/farmacología , Escherichia coli/efectos de los fármacos , Indio/química , Indio/farmacología , Luz , Nanoestructuras/química , Nanoestructuras/efectos de la radiación , Fotoquímica/métodos , Fototerapia , Staphylococcus aureus/efectos de los fármacos , Streptococcus pyogenes/efectos de los fármacos , Titanio/química
19.
Int J Biochem Cell Biol ; 42(11): 1831-9, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20691807

RESUMEN

The human papillomavirus (HPV) oncoprotein E7 is a major transforming protein. The E7 protein does not possess intrinsic enzymatic activity, but rather functions through direct and indirect interactions with cellular proteins, several of which are well known cellular tumor suppressors. Using the yeast two-hybrid system, we found that transforming growth factor-beta inducible early gene 1 (TIEG1), a member of the Krüppel-like family (KLF) that has been implicated as a putative tumor suppressor, interacts and forms a specific complex with HPV-16 E7. TIEG1 has been shown to mimic the effects of TGF-beta in various carcinoma cells and plays a critical role in the apoptotic cascade. Our results indicate that E7 binds to the C-terminus of TIEG1 and induces its degradation via the ubiquitin pathway. E7 not only increased the ubiquitination of TIEG1 but also influenced the ability of TIEG1 to affect apoptosis. Our results suggest that suppression of TIEG1-mediated signaling by E7 may contribute to HPV-associated carcinogenesis.


Asunto(s)
Apoptosis/fisiología , Factores de Transcripción de la Respuesta de Crecimiento Precoz/metabolismo , Papillomavirus Humano 16/metabolismo , Factores de Transcripción de Tipo Kruppel/metabolismo , Proteínas Oncogénicas/metabolismo , Apoptosis/genética , Western Blotting , Línea Celular Tumoral , Fragmentación del ADN , Factores de Transcripción de la Respuesta de Crecimiento Precoz/genética , Citometría de Flujo , Papillomavirus Humano 16/genética , Humanos , Inmunohistoquímica , Inmunoprecipitación , Factores de Transcripción de Tipo Kruppel/genética , Microscopía Confocal , Proteínas Oncogénicas/genética , Técnicas del Sistema de Dos Híbridos , Ubiquitinación
20.
J Biol Chem ; 283(23): 15681-8, 2008 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-18408009

RESUMEN

HPV-16E7 is a major transforming protein, which has been implicated in the development of cervical cancer. The stability of E7 is thus important to ensure its fully functional status. Using the yeast two-hybrid system, we found that USP11 (ubiquitin-specific protease 11), a member of a protein family that cleaves polyubiquitin chains and/or ubiquitin precursors, interacts and forms a specific complex with HPV-16E7. Our results indicate that the USP11 can greatly increase the steady state level of HPV-16E7 by reducing ubiquitination and attenuating E7 degradation. In contrast, a catalytically inactive mutant of USP11 abolished the deubiquitinating ability and returned E7 to a normal rate of degradation. Moreover, USP11 not only protected E7 from ubiquitination but also influenced E7 function as a modulator of cell growth status. These results suggest that USP11 plays an important role in regulating the levels of E7 protein and subsequently affects the biological function of E7 as well as its contribution to cell transformation by HPV-16E7.


Asunto(s)
Transformación Celular Viral , Papillomavirus Humano 16/metabolismo , Proteínas Oncogénicas Virales/metabolismo , Tioléster Hidrolasas/metabolismo , Ubiquitinación , Transformación Celular Viral/genética , Femenino , Papillomavirus Humano 16/genética , Humanos , Proteínas Oncogénicas Virales/genética , Proteínas E7 de Papillomavirus , Tioléster Hidrolasas/genética , Técnicas del Sistema de Dos Híbridos , Ubiquitinación/genética , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/virología
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