Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Hu Li Za Zhi ; 71(3): 6-12, 2024 Jun.
Artículo en Zh | MEDLINE | ID: mdl-38817131

RESUMEN

Recent, rapid advancements in technology have enabled the introduction and integration of robots into everyday life. Different from the traditional image of robots as cold and mechanical, social robots are designed to emulate human interaction patterns, improving the user experience and facilitating social interactivity. Thus, social robots represent a promising new care intervention. In this article, after defining social robots and explaining the factors influencing "human-robot interaction", the authors discuss the effectiveness of social robots in the context of providing care to patients with dementia and autism as well as to pediatric patients. Finally, current cases in which PARO, a social robot, has been used in nursing are described, and key challenges and suggestions for future social robot applications are given. Current evidence indicates social robots must be developed and designed to adhere to a people-centered approach to achieve better robot-assisted care outcomes, be better accepted by patients, and better enable patients to open up emotionally and maintain good physical, mental, and social well-being.


Asunto(s)
Enfermería , Robótica , Humanos , Robótica/métodos
2.
Cell Mol Life Sci ; 79(7): 348, 2022 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-35670884

RESUMEN

Chronic obstructive pulmonary disease (COPD) is a progressive lung disease with high morbidity and mortality worldwide. Although several mechanisms to account for deleterious immune effects were proposed, molecular description for the underlying alveolar structural alterations for COPD is lacking. Here, silencing of α1,6-fucosyltransferase (Fut8), the enzyme for core-fucosylation and highly expressed in lung stem cells, resulted in alveolar structural changes in lung organoids, recapitulating COPD. Site-specific mass spectrometry analysis demonstrated that the secreted protein acidic and rich in cysteine (SPARC), which binds collagen, contains a core-fucosylation site in its VCSNDNcfK glycopeptide. Biacore assay showed markedly reduced collagen binding of SPARC lacking core fucosylation. Molecular dynamics analysis revealed that core fucosylation of SPARC-induced dynamic conformational changes in its N-glycan, allowing terminal galactose and N-acetylglucosamine to interact with K150, P261 and H264 residues, thereby promoting collagen binding. Site-specific mutagenesis of these residues also resulted in low affinity for collagen binding. Moreover, loss of collagen and decline of core fucosylation were observed in COPD lung tissues. These findings provide a new mechanistic insight into the role of core fucosylation of SPARC in cell-matrix communication and contribution to the abnormal alveolar structures in COPD.


Asunto(s)
Osteonectina , Enfermedad Pulmonar Obstructiva Crónica , Colágeno/metabolismo , Fucosiltransferasas/genética , Fucosiltransferasas/metabolismo , Glicosilación , Humanos , Osteonectina/genética , Osteonectina/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/genética
3.
J Biomed Sci ; 27(1): 93, 2020 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-32900381

RESUMEN

The use of in silico strategies to develop the structural basis for a rational optimization of glycan-protein interactions remains a great challenge. This problem derives, in part, from the lack of technologies to quantitatively and qualitatively assess the complex assembling between a glycan and the targeted protein molecule. Since there is an unmet need for developing new sugar-targeted therapeutics, many investigators are searching for technology platforms to elucidate various types of molecular interactions within glycan-protein complexes and aid in the development of glycan-targeted therapies. Here we discuss three important technology platforms commonly used in the assessment of the complex assembly of glycosylated biomolecules, such as glycoproteins or glycosphingolipids: Biacore analysis, molecular docking, and molecular dynamics simulations. We will also discuss the structural investigation of glycosylated biomolecules, including conformational changes of glycans and their impact on molecular interactions within the glycan-protein complex. For glycoproteins, secreted protein acidic and rich in cysteine (SPARC), which is associated with various lung disorders, such as chronic obstructive pulmonary disease (COPD) and lung cancer, will be taken as an example showing that the core fucosylation of N-glycan in SPARC regulates protein-binding affinity with extracellular matrix collagen. For glycosphingolipids (GSLs), Globo H ceramide, an important tumor-associated GSL which is being actively investigated as a target for new cancer immunotherapies, will be used to demonstrate how glycan structure plays a significant role in enhancing angiogenesis in tumor microenvironments.


Asunto(s)
Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Osteonectina/química , Polisacáridos/química , Glicosilación , Unión Proteica
4.
Stem Cells ; 36(10): 1514-1524, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29893054

RESUMEN

Stem cell surface markers may facilitate a better understanding of stem cell biology through molecular function studies or serve as tools to monitor the differentiation status and behavior of stem cells in culture or tissue. Thus, it is important to identify additional novel stem cell markers. We used glycoproteomics to discover surface glycoproteins on human embryonic stem cells (hESCs) that may be useful stem cell markers. We found that a surface glycoprotein, leucine-rich repeat neuronal protein 1 (LRRN1), is expressed abundantly on the surface of hESCs before differentiation into embryoid bodies (EBs). Silencing of LRRN1 with short hairpin RNA (shLRRN1) in hESCs resulted in decreased capacity of self-renewal, and skewed differentiation toward endoderm/mesoderm lineages in vitro and in vivo. Meanwhile, the protein expression levels of the pluripotency factors OCT4, NANOG, and SOX2 were reduced. Interestingly, the mRNA levels of these pluripotency factors were not affected in LRRN1 silenced cells, but protein half-lives were substantially shortened. Furthermore, we found LRRN1 silencing led to nuclear export and proteasomal degradation of all three pluripotency factors. In addition, the effects on nuclear export were mediated by AKT phosphorylation. These results suggest that LRRN1 plays an important role in maintaining the protein stability of pluripotency factors through AKT phosphorylation, thus maintaining hESC self-renewal capacity and pluripotency. Overall, we found that LRRN1 contributes to pluripotency of hESC by preventing translocation of OCT4, NANOG, and SOX2 from nucleus to cytoplasm, thereby lessening their post-translational modification and degradation. Stem Cells 2018;36:1514-1524.


Asunto(s)
Células Madre Embrionarias/metabolismo , Proteínas de la Membrana/metabolismo , Proteína Homeótica Nanog/metabolismo , Proteínas de Neoplasias/metabolismo , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Células Madre Pluripotentes/metabolismo , Factores de Transcripción SOXB1/metabolismo , Diferenciación Celular/fisiología , Células Madre Embrionarias/citología , Humanos , Proteína Homeótica Nanog/biosíntesis , Proteína Homeótica Nanog/genética , Proteínas del Tejido Nervioso , Factor 3 de Transcripción de Unión a Octámeros/biosíntesis , Factor 3 de Transcripción de Unión a Octámeros/genética , Células Madre Pluripotentes/citología , Procesamiento Proteico-Postraduccional , Estabilidad Proteica , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factores de Transcripción SOXB1/biosíntesis , Factores de Transcripción SOXB1/genética
5.
Sensors (Basel) ; 19(6)2019 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-30875851

RESUMEN

Time-domain reflectometry (TDR) has been a powerful tool for measuring soil dielectric properties. Initiating from apparent dielectric constant ( K a ) measurement up until apparent and complex dielectric spectroscopies, the embedded information in the TDR signal can be extracted to inspire our understanding of the underlying dielectric behaviors. Multiple full waveform inversion techniques have been developed to extract complex dielectric permittivity (CDP) spectrum, but most of them involved prior knowledge of input function and tedious calibration. This rendered the field dielectric spectroscopy challenging and expensive to conduct. Dual reflection analysis (DRA) is proposed in this study to measure CDP spectrum from 10 MHz to 1 GHz. DRA is a simple, robust, model-free, and source-function free algorithm which requires minimal calibration effort. The theoretical framework of DRA is established and the necessary signal processing procedures are elaborated in this study. Eight materials with different dielectric characteristics are selected to evaluate DRA's performance, by using both simulated and experimental signals. DRA is capable of measuring non-dispersive materials very well, whereas dispersive materials require the assistance of a long-time-window (LTW) extraction method to further extend the effective bandwidth. The DRA approach is suitable for field applications that can only record a limited amount of data points and in-situ dielectric spectroscopy.

6.
Plant Sci ; 344: 112080, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38582272

RESUMEN

Chamaecyparis obtusa and C. obtusa var. formosana of the Cupressaceae family are well known for their fragrance and excellent physical properties. To investigate the biosynthesis of unique diterpenoid compounds, diterpene synthase genes for specialized metabolite synthesis were cloned from C. obtusa and C. obtusa var. formosana. Using an Escherichia coli co-expression system, eight diterpene synthases (diTPSs) were characterized. CoCPS and CovfCPS are class II monofunctional (+)-copalyl diphosphate synthases [(+)-CPSs]. Class I monofunctional CoLS and CovfLS convert (+)-copalyl diphosphate [(+)-CPP] to levopimaradiene, CoBRS, CovfBRS1, and CovfBRS3 convert (+)-CPP to (-)-beyerene, and CovfSDS converts (+)-CPP to (-)-sandaracopimaradiene. These enzymes are all monofunctional diterpene syntheses in Cupressaceae family of gymnosperm, and differ from those in Pinaceae. The discovery of the enzyme responsible for the biosynthesis of tetracyclic diterpene (-)-beyerene was characterized for the first time. Diterpene synthases with different catalytic functions exist in closely related species within the Cupressaceae family, indicating that this group of monofunctional diterpene synthases is particularly prone to the evolution of new functions and development of species-specific specialized diterpenoid constituents.


Asunto(s)
Transferasas Alquil y Aril , Chamaecyparis , Diterpenos , Filogenia , Diterpenos/metabolismo , Chamaecyparis/genética , Chamaecyparis/metabolismo , Chamaecyparis/enzimología , Transferasas Alquil y Aril/genética , Transferasas Alquil y Aril/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Cupressaceae/genética , Cupressaceae/metabolismo , Cupressaceae/enzimología , Evolución Molecular
7.
J Agric Food Chem ; 69(42): 12494-12504, 2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34664500

RESUMEN

Zanthoxylum ailanthoides is a traditional spice crop in Taiwan with unique smells and tastes that differ between prickly (young) and nonprickly (mature) leaves. Different volatile terpenes between prickly young and nonprickly mature leaves were identified and considered to be one of the sources of their aromas. A transcriptome database was established to explore the biosynthesis of these compounds, and candidate terpene synthase genes were identified. The functions of these synthases were investigated using recombinant protein reactions in both purification and coexpression assays. ZaTPS1, ZaTPS2, and ZaTPS3 are germacrene D synthases, with different amino acid sequences. The main products of ZaTPS4 are trans-α-bergamotene and (E)-ß-farnesene, whereas ZaTPS5 forms multiple products, and ZaTPS6 produces ß-caryophyllene. ZaTPS7 forms monoterpene (E)-ß-ocimene and sesquiterpene (E,E)-α-farnesene. Reverse transcription PCR of ZaTPS gene expression in young and mature leaves revealed that ZaTPS1 was responsible for the mellow aroma in mature leaves. The expression of ZaTPS6 suggested that it plays a role in the background aromas of both types of leaves. Our findings deepened the understanding of the volatile compounds of Z. ailanthoides and revealed the source of its unique aromas by clarifying the biosynthesis of these compounds.


Asunto(s)
Transferasas Alquil y Aril , Sesquiterpenos , Compuestos Orgánicos Volátiles , Zanthoxylum , Transferasas Alquil y Aril/genética , Folclore , Odorantes , Proteínas de Plantas/genética , Taiwán , Terpenos/análisis
8.
FASEB J ; 23(7): 2076-87, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19246485

RESUMEN

Recent studies indicate that neonatal spermatogonial stem cells (SSCs) possess pluripotency. However, the mechanisms that regulate the pluripotent differentiation capacity of SSCs remain unclear. Here, we describe a new method to clonally derive pluripotent SSCs from neonatal mouse testis. By coculturing with testicular stromal cells, SSCs can be maintained and expanded in serum-free conditions. Unlike endogenous SSCs, these in vitro expanded SSCs showed strong alkaline phosphatase (AP) activity and displayed characteristics of embryonic stem cells and primordial germ cells, which were therefore designated as AP(+) germline stem cells (AP(+)GSCs). The pluripotency of AP(+)GSCs was confirmed by in vitro differentiation toward hepatic and neuronal lineages and formation of embryonic chimeras after injection into blastocysts. Further investigation revealed that insulin-like growth factor-1 (IGF-1) secreted from Leydig cells was a key factor involved in maintaining the pluripotency of AP(+)GSCs. The blockage of IGF-1 receptor phosphorylation and its downstream PI3K pathway by PPP or LY294002 dramatically reduced their AP activity and expression of pluripotent genes, such as Oct-4, Blimp1, and Nanog. In conclusion, the present study demonstrated that IGF-1 secreted by testicular Leydig cells plays an important role in maintaining the pluripotency of SSCs in culture, which provides an insight into the molecular mechanism underlying germ cell pluripotency.


Asunto(s)
Factor I del Crecimiento Similar a la Insulina/metabolismo , Células Madre Pluripotentes/citología , Espermatogonias/citología , Animales , Animales Recién Nacidos , Linaje de la Célula , Factor I del Crecimiento Similar a la Insulina/fisiología , Células Intersticiales del Testículo/metabolismo , Masculino , Ratones , Comunicación Paracrina , Testículo/citología
9.
Stem Cells Int ; 2020: 6312053, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33061990

RESUMEN

The lung is a radiosensitive organ, which imposes limits on the therapeutic dose in thoracic radiotherapy. Irradiated alveolar epithelial cells promote radiation-related pneumonitis and fibrosis. However, the role of lung stem cells (LSCs) in the development of radiation-induced lung injury is still unclear. In this study, we found that both LSCs and LSC-derived type II alveolar epithelial cells (AECII) can repair radiation-induced DNA double-strand breaks, but the irradiated LSCs underwent growth arrest and cell differentiation faster than the irradiated AECII cells. Moreover, radiation drove LSCs to fibrosis as shown with the elevated levels of markers for epithelial-mesenchymal transition and myofibroblast (α-smooth muscle actin (α-SMA)) differentiation in in vitro and ex vivo studies. Increased gene expressions of connective tissue growth factor and α-SMA were found in both irradiated LSCs and alveolar cells, suggesting that radiation could induce the fibrogenic differentiation of LSCs. Irradiated LSCs showed an increase in the expression of surfactant protein C (SP-C), the AECII cell marker, and α-SMA, and irradiated AECII cells expressed SP-C and α-SMA. These results indicated that radiation induced LSCs to differentiate into myofibroblasts and AECII cells; then, AECII cells differentiated further into either myofibroblasts or type I alveolar epithelial cells (AECI). In conclusion, our results revealed that LSCs are sensitive to radiation-induced cell damage and may be involved in radiation-induced lung fibrosis.

10.
Nat Nanotechnol ; 8(9): 682-9, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23912062

RESUMEN

Lung stem/progenitor cells are potentially useful for regenerative therapy, for example in repairing damaged or lost lung tissue in patients. Several optical imaging methods and probes have been used to track how stem cells incorporate and regenerate themselves in vivo over time. However, these approaches are limited by photobleaching, toxicity and interference from background tissue autofluorescence. Here we show that fluorescent nanodiamonds, in combination with fluorescence-activated cell sorting, fluorescence lifetime imaging microscopy and immunostaining, can identify transplanted CD45(-)CD54(+)CD157(+) lung stem/progenitor cells in vivo, and track their engraftment and regenerative capabilities with single-cell resolution. Fluorescent nanodiamond labelling did not eliminate the cells' properties of self-renewal and differentiation into type I and type II pneumocytes. Time-gated fluorescence imaging of tissue sections of naphthalene-injured mice indicates that the fluorescent nanodiamond-labelled lung stem/progenitor cells preferentially reside at terminal bronchioles of the lungs for 7 days after intravenous transplantation.


Asunto(s)
Diferenciación Celular , Colorantes Fluorescentes/farmacología , Pulmón/citología , Nanodiamantes , Trasplante de Células Madre , Células Madre/citología , Aloinjertos , Animales , Antígenos CD/metabolismo , Pulmón/metabolismo , Ratones , Ratones Endogámicos ICR , Microscopía Fluorescente/métodos , Medicina Regenerativa/métodos , Células Madre/metabolismo
11.
J Hazard Mater ; 190(1-3): 938-44, 2011 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-21555185

RESUMEN

An optimal condition applied to the Taguchi method with an L(9) orthogonal array for preparing a visible-light driven nitrogen-modified TiO(2) (N-TiO(2)) photocatalyst by a simple hydrolysis method has been examined for material characteristics and a photodecolorization test of methyl blue (MB) under various visible light source (fluorescent and blue LED lamps) irradiations. Results of the material characterization showed that the absorption of prepared N-TiO(2) powder exhibited a significant extension into visible light regimes with an optical bandgap (Eg) of around 2.96 eV, which subsequently improved the visible-light photocatalytic activity of N-TiO(2) samples. The superior photocatalytic properties, the pseudo first-order reaction rate constants (k) and photodecolorization efficiency (η%) of a N-TiO(2) photocatalyst during the photodecolorization test of methyl blue (MB) under two different visible light irradiations were very evident compared to those for pure TiO(2). For photodecolorization of practical dyeing from the waste water from the dyeing and finishing industry, a higher photodecolorization efficiency of N-TiO(2) powder toward Direct blue-86 (DB-86) (Direct Fast Turquoise Blue GL) dye was also achieved.


Asunto(s)
Luz , Nitrógeno/química , Fotólisis , Titanio/química , Bencenosulfonatos/química , Bencenosulfonatos/efectos de la radiación , Catálisis , Hidrólisis , Cinética , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/efectos de la radiación , Purificación del Agua/métodos
12.
Proc Natl Acad Sci U S A ; 103(25): 9530-5, 2006 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-16772384

RESUMEN

In this study, we report a serum-free culture system for primary neonatal pulmonary cells that can support the growth of octamer-binding transcription factor 4+ (Oct-4+) epithelial colonies with a surrounding mesenchymal stroma. In addition to Oct-4, these cells also express other stem cell markers such as stage-specific embryonic antigen 1 (SSEA-1), stem cell antigen 1 (Sca-1), and Clara cell secretion protein (CCSP) but not c-Kit, CD34, and p63, indicating that they represent a subpopulation of Clara cells that have been implicated as lung stem/progenitor cells in lung injury models. These colony cells can be kept for weeks in primary cultures and undergo terminal differentiation to alveolar type-2- and type-1-like pneumocytes sequentially when removed from the stroma. In addition, we have demonstrated the presence of Oct-4+ long-term BrdU label-retaining cells at the bronchoalveolar junction of neonatal lung, providing a link between the Oct-4+ cells in vivo and in vitro and strengthening their identity as putative neonatal lung stem/progenitor cells. Lastly, these Oct-4+ epithelial colony cells, which also express angiotensin-converting enzyme 2, are the target cells for severe acute respiratory syndrome coronavirus infection in primary cultures and support active virus replication leading to their own destruction. These observations imply the possible involvement of lung stem/progenitor cells, in addition to pneumocytes, in severe acute respiratory syndrome coronavirus infection, accounting for the continued deterioration of lung tissues and apparent loss of capacity for lung repair.


Asunto(s)
Pulmón/citología , Pulmón/virología , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/fisiología , Células Madre/metabolismo , Células Madre/virología , Animales , Biomarcadores , Bromodesoxiuridina , Diferenciación Celular , Células Cultivadas , Células Epiteliales/citología , Células Epiteliales/metabolismo , Células Epiteliales/virología , Regulación de la Expresión Génica , Ratones , Ratones Endogámicos ICR , Microscopía Electrónica de Transmisión , Células Madre/citología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA