Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 41
Filtrar
1.
Pharmaceuticals (Basel) ; 17(10)2024 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-39459006

RESUMEN

Although mesenchymal stem cells (MSCs) insertion has gained recent attention as a joint-preserving procedure, no study has conducted direct intralesional implantation of human umbilical cord-derived MSCs (hUCMSCs) in patients with ONFH. This is a protocol for a phase 1 clinical trial designed to assess the safety and exploratory efficacy of human umbilical cord-derived osteoblasts (hUC-Os), osteogenic differentiation-induced cells from hUCMSCs, in patients with early-stage ONFH. Nine patients with Association Research Circulation Osseous (ARCO) stage 1 or 2 will be assigned to a low-dose (1 × 107 hUC-O cells, n = 3), medium-dose (2 × 107 cells, n = 3), and high-dose group (4 × 107 cells, n = 3) in the order of their arrival at the facility, and, depending on the occurrence of dose-limiting toxicity, up to 18 patients can be enrolled by applying the 3 + 3 escalation method. We will perform hUC-O (CF-M801) transplantation combined with core decompression and follow-up for 12 weeks according to the study protocol. Safety will be determined through adverse event assessment, laboratory tests including a panel reactive antibody test, vital sign assessment, physical examination, and electrocardiogram. Efficacy will be explored through the change in pain visual analog scale, Harris hip score, Western Ontario and McMaster Universities Osteoarthritis Index, ARCO stage, and also size and location of necrotic lesion according to Japanese Investigation Committee classification before and after the procedure. Joint preservation is important, particularly in younger, active patients with ONFH. Confirmation of the safety and efficacy of hUC-Os will lead to a further strategy to preserve joints for those suffering from ONFH and improve our current knowledge of cell therapy.

2.
Bioengineering (Basel) ; 10(11)2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-38002434

RESUMEN

The complex process of bone regeneration is influenced by factors such as inflammatory responses, tissue interactions, and progenitor cells. Currently, multiple traumas can interfere with fracture healing, causing the prolonging or failure of healing. In these cases, bone grafting is the most effective treatment. However, there are several drawbacks, such as morbidity at the donor site and availability of suitable materials. Advantages have been provided in this field by a variety of stem cell types. Adipose-derived stem cells (ASCs) show promise. In the radiological examination of this study, it was confirmed that the C/S group showed faster regeneration than the other groups, and Micro-CT also showed that the degree of bone formation in the defect area was highest in the C/S group. Compared to the control group, the change in cortical bone area in the defect area decreased in the sham group (0.874), while it slightly increased in the C/S group (1.027). An increase in relative vascularity indicates a decrease in overall bone density, but a weak depression filled with fibrous tissue was observed outside the compact bone. It was confirmed that newly formed cortical bone showed a slight difference in bone density compared to surrounding normal bone tissue due to increased distribution of cortical bone. In this study, we investigated the effect of bone regeneration by ADMSCs measured by radiation and pathological effects. These data can ultimately be applied to humans with important clinical applications in various bone diseases, regenerative, and early stages of formative differentiation.

3.
Adv Sci (Weinh) ; 10(33): e2305096, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37845006

RESUMEN

Despite advances in precision oncology, cancer remains a global public health issue. In this report, proof-of-principle evidence is presented that a cell-penetrable peptide (ACP52C) dissociates transcription factor CP2c complexes and induces apoptosis in most CP2c oncogene-addicted cancer cells through transcription activity-independent mechanisms. CP2cs dissociated from complexes directly interact with and degrade YY1, leading to apoptosis via the MDM2-p53 pathway. The liberated CP2cs also inhibit TDP2, causing intrinsic genome-wide DNA strand breaks and subsequent catastrophic DNA damage responses. These two mechanisms are independent of cancer driver mutations but are hindered by high MDM2 p60 expression. However, resistance to ACP52C mediated by MDM2 p60 can be sensitized by CASP2 inhibition. Additionally, derivatives of ACP52C conjugated with fatty acid alone or with a CASP2 inhibiting peptide show improved pharmacokinetics and reduced cancer burden, even in ACP52C-resistant cancers. This study enhances the understanding of ACP52C-induced cancer-specific apoptosis induction and supports the use of ACP52C in anticancer drug development.


Asunto(s)
Proteínas de Unión al ADN , Neoplasias , Humanos , Proteínas de Unión al ADN/genética , Neoplasias/genética , Mutaciones Letales Sintéticas , Medicina de Precisión , Factores de Transcripción/genética , Péptidos , Hidrolasas Diéster Fosfóricas/genética
4.
Int J Mol Sci ; 24(6)2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-36982869

RESUMEN

The nanoscale spatiotemporal resolution of single-particle tracking (SPT) renders it a powerful method for exploring single-molecule dynamics in living cells or tissues, despite the disadvantages of using traditional organic fluorescence probes, such as the weak fluorescent signal against the strong cellular autofluorescence background coupled with a fast-photobleaching rate. Quantum dots (QDs), which enable tracking targets in multiple colors, have been proposed as an alternative to traditional organic fluorescence dyes; however, they are not ideally suitable for applying SPT due to their hydrophobicity, cytotoxicity, and blinking problems. This study reports an improved SPT method using silica-coated QD-embedded silica nanoparticles (QD2), which represent brighter fluorescence and are less toxic than single QDs. After treatment of QD2 in 10 µg/mL, the label was retained for 96 h with 83.76% of labeling efficiency, without impaired cell function such as angiogenesis. The improved stability of QD2 facilitates the visualization of in situ endothelial vessel formation without real-time staining. Cells retain QD2 fluorescence signal for 15 days at 4 °C without significant photobleaching, indicating that QD2 has overcome the limitations of SPT enabling long-term intracellular tracking. These results proved that QD2 could be used for SPT as a substitute for traditional organic fluorophores or single quantum dots, with its photostability, biocompatibility, and superior brightness.


Asunto(s)
Nanopartículas , Puntos Cuánticos , Humanos , Dióxido de Silicio , Células Endoteliales de la Vena Umbilical Humana , Línea Celular , Colorantes Fluorescentes
5.
Commun Biol ; 4(1): 544, 2021 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-33972689

RESUMEN

Actin-Related Protein-Testis1 (ARP-T1)/ACTRT1 gene mutations cause the Bazex-Dupré-Christol Syndrome (BDCS) characterized by follicular atrophoderma, hypotrichosis, and basal cell cancer. Here, we report an ARP-T1 interactome (PXD016557) that includes proteins involved in ciliogenesis, endosomal recycling, and septin ring formation. In agreement, ARP-T1 localizes to the midbody during cytokinesis and the basal body of primary cilia in interphase. Tissue samples from ARP-T1-associated BDCS patients have reduced ciliary length. The severity of the shortened cilia significantly correlates with the ARP-T1 levels, which was further validated by ACTRT1 knockdown in culture cells. Thus, we propose that ARP-T1 participates in the regulation of cilia length and that ARP-T1-associated BDCS is a case of skin cancer with ciliopathy characteristics.


Asunto(s)
Carcinoma Basocelular/patología , Cilios/patología , Ciliopatías/patología , Hipotricosis/patología , Queratinocitos/patología , Proteínas de Microfilamentos/metabolismo , Neoplasias Basocelulares/patología , Neoplasias Cutáneas/patología , Carcinoma Basocelular/genética , Carcinoma Basocelular/metabolismo , Cilios/metabolismo , Ciliopatías/genética , Ciliopatías/metabolismo , Humanos , Hipotricosis/genética , Hipotricosis/metabolismo , Queratinocitos/metabolismo , Proteínas de Microfilamentos/genética , Mutación , Neoplasias Basocelulares/genética , Neoplasias Basocelulares/metabolismo , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/metabolismo
6.
J Clin Med ; 9(11)2020 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-33172126

RESUMEN

This study was performed to evaluate the anticancer effects of tolerable doses of metformin with or without medroxyprogesterone (MPA) in endometrial cancer cells. Cell viability, cell invasion, and levels of matrix metallopeptidase (MMP) and transforming growth factor (TGF)-ß1 were analyzed using three human endometrial adenocarcinoma cell lines (Ishikawa, KLE, and uterine serous papillary cancer (USPC)) after treatment with different dose combinations of MPA and metformin. Combining metformin (0, 100, 1000 µM) and 10 µM MPA induced significantly decreased cell viability in a time- and dose-dependent manner in Ishikawa cells, but not in KLE and USPC cells. In KLE cells, metformin treatment alone significantly inhibited cell invasion in a dose-dependent manner. The inhibitory effect of metformin was reversed when 10 µM MPA was combined, which was significantly inhibited again after treatment of MMP-2/9 inhibitor and/or TGF-ß inhibitor. Changes of MMP-9 and TGF-ß1 according to combinations of MPA and metformin were similar to those of invasion in KLE cells. In conclusion, the anticancer effects of tolerable doses of metformin varied according to cell type and combinations with MPA. Anti-invasive effect of metformin in KLE cells was completely reversed by the addition of MPA; this might be associated with MMP-9 and TGF-ß1.

7.
Cell Cycle ; 18(21): 2954-2971, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31505996

RESUMEN

In previous work, we established an equine induced pluripotent stem cell line (E-iPSCs) from equine adipose-derived stem cells (ASCs) using a lentiviral vector encoding four transcription factors: Oct4, Sox2, Klf4, and c-Myc. In the current study, we attempted to differentiate these established E-iPSCs into mesenchymal stem cells (MSCs) by serial passaging using MSC-defined media for stem cell expansion. Differentiation of the MSCs was confirmed by analyzing expression levels of the MSC surface markers CD44 and CD29, and the pluripotency markers Nanog and Oct4. Results indicated that the E-iPSC-derived MSCs (E-iPSC-MSCs) retained the characteristics of MSCs, including the ability to differentiate into chondrogenic, osteogenic, or myogenic lineages. E-iPSC-MSCs were rendered suitable for therapeutic use by inhibiting immune rejection through exposure to transforming growth factor beta 2 (TGF-ß2) in culture, which down-regulated the expression of major histocompatibility complex class I (MHC class I) proteins that cause immune rejection if they are incompatible with the MHC antigen of the recipient. We reported 16 cases of E-iPSC-MSC transplantations into injured horses with generally positive effects, such as reduced lameness and fraction lines. Our findings indicate that E-iPSC-MSCs can demonstrate MSC characteristics and be safely and practically used in the treatment of musculoskeletal injuries in horses.


Asunto(s)
Diferenciación Celular/fisiología , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Rechazo de Injerto/prevención & control , Células Madre Pluripotentes Inducidas/citología , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/citología , Adipocitos/citología , Tejido Adiposo/citología , Animales , Desarrollo Óseo/fisiología , Células Cultivadas , Condrocitos/citología , Condrogénesis/fisiología , Rechazo de Injerto/inmunología , Caballos , Factor 4 Similar a Kruppel , Células Musculares/citología , Desarrollo de Músculos/fisiología , Músculo Esquelético/lesiones , Osteocitos/citología , Factor de Crecimiento Transformador beta2/metabolismo
8.
Cell Death Dis ; 9(11): 1092, 2018 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-30361642

RESUMEN

Life-long regeneration of healthy muscle by cell transplantation is an ideal therapy for patients with degenerative muscle diseases. Yet, obtaining muscle stem cells from patients is very limited due to their exhaustion in disease condition. Thus, development of a method to obtain healthy myogenic stem cells is required. Here, we showed that the four transcription factors, Six1, Eya1, Esrrb, and Pax3, converts fibroblasts into induced myogenic stem cells (iMSCs). The iMSCs showed effective differentiation into multinucleated myotubes and also higher proliferation capacity than muscle derived stem cells both in vitro and in vivo. The iMSCs do not lose their proliferation capacity though the passaging number is increased. We further isolated CD106-negative and α7-integrin-positive iMSCs (sort-iMSCs) showing higher myogenic differentiation capacity than iMSCs. Moreover, genome-wide transcriptomic analysis of iMSCs and sort-iMSCs, followed by network analysis, revealed the genes and signaling pathways associated with enhanced proliferation and differentiation capacity of iMSCs and sort-iMSCs, respectively. The stably expandable iMSCs provide a new source for drug screening and muscle regenerative therapy for muscle wasting disease.


Asunto(s)
Reprogramación Celular , Fibroblastos/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Mioblastos/metabolismo , Factores de Transcripción/metabolismo , Animales , Antígenos CD/metabolismo , Puntos de Control del Ciclo Celular , Diferenciación Celular/fisiología , Proliferación Celular/fisiología , Distrofina/metabolismo , Femenino , Cadenas alfa de Integrinas/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL/embriología , Ratones Endogámicos mdx , Ratones Desnudos , Desarrollo de Músculos , Distrofias Musculares/terapia , Embarazo , ARN Mensajero/genética , Trasplante de Células Madre , Trasplante Autólogo , Molécula 1 de Adhesión Celular Vascular/metabolismo
9.
Nat Med ; 23(10): 1226-1233, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28869610

RESUMEN

Basal cell carcinoma (BCC), the most common human cancer, results from aberrant activation of the Hedgehog signaling pathway. Although most cases of BCC are sporadic, some forms are inherited, such as Bazex-Dupré-Christol syndrome (BDCS)-a cancer-prone genodermatosis with an X-linked, dominant inheritance pattern. We have identified mutations in the ACTRT1 gene, which encodes actin-related protein T1 (ARP-T1), in two of the six families with BDCS that were examined in this study. High-throughput sequencing in the four remaining families identified germline mutations in noncoding sequences surrounding ACTRT1. These mutations were located in transcribed sequences encoding enhancer RNAs (eRNAs) and were shown to impair enhancer activity and ACTRT1 expression. ARP-T1 was found to directly bind to the GLI1 promoter, thus inhibiting GLI1 expression, and loss of ARP-T1 led to activation of the Hedgehog pathway in individuals with BDCS. Moreover, exogenous expression of ACTRT1 reduced the in vitro and in vivo proliferation rates of cell lines with aberrant activation of the Hedgehog signaling pathway. In summary, our study identifies a disease mechanism in BCC involving mutations in regulatory noncoding elements and uncovers the tumor-suppressor properties of ACTRT1.


Asunto(s)
Carcinoma Basocelular/genética , Hipotricosis/genética , Proteínas de Microfilamentos/genética , Neoplasias Cutáneas/genética , Animales , Sistemas CRISPR-Cas , Inmunoprecipitación de Cromatina , Elementos de Facilitación Genéticos/genética , Femenino , Perfilación de la Expresión Génica , Proteínas Hedgehog/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Ratones , Ratones Desnudos , Mutación , Trasplante de Neoplasias , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Transducción de Señal
10.
Mitochondrion ; 37: 27-40, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28669809

RESUMEN

Mitochondria dysfunction plays a role in many human diseases. Therapeutic techniques for these disorders require novel delivery systems that can specifically target and penetrate mitochondria. In this study, we report a novel nanosome composed of dequalinium-DOTAP-DOPE (1,2 dioleoyl-3-trimethylammonium-propane-1,2-dioleoyl-sn-glycero-3-phosphoethanolamine) (DQA80s) as a potential mitochondria-targeting delivery vector. The functional DQAsome, DQA80s, showed enhanced transfection efficiency compared to a vector DQAsomes in HeLa cells and dermal fibroblasts. In addition, DQA80s/pDNA complexes exhibited rapid escape from the endosome into the cytosol. We observed the delivery of pDNA to mitochondria in living cells using flow cytometry, confocal microscopy, and TME imaging. More specifically, we confirmed our results by co-localization of hmtZsGreen constructs to mitochondria when delivered via DQAsomes and DQA80s in living cells. The mitochondria-targeting DQAsomes and DQA80s induced mitochondrial dysfunction through depolarization of mitochondrial membrane potential. Our data demonstrate that DQA80s show promise for use as a mitochondria-targeted carrier system for treatment of mitochondria diseases in vivo.


Asunto(s)
Marcación de Gen/métodos , Técnicas de Transferencia de Gen , Mitocondrias/genética , Biología Molecular/métodos , Nanopartículas , Fibroblastos , Células HeLa , Humanos , Transfección
11.
J Invest Dermatol ; 136(5): 905-911, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27017330

RESUMEN

The homeodomain-only protein homeobox (HOPX) is the smallest known member of the homeodomain-containing protein family, atypically unable to bind DNA. HOPX is widely expressed in diverse tissues, where it is critically involved in the regulation of proliferation and differentiation. In human skin, HOPX controls epidermal formation through the regulation of late differentiation markers, and HOPX expression correlates with the level of differentiation in cutaneous pathologies. In mouse skin, Hopx was additionally identified as a lineage tracing marker of quiescent hair follicle stem cells. This review discusses current knowledge of HOPX structure and function in normal and pathological conditions.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Genes Homeobox/genética , Proteínas de Homeodominio/genética , Neoplasias Cutáneas/genética , Animales , Diferenciación Celular/genética , Proliferación Celular/genética , Metilación de ADN , Humanos , Ratones , Sensibilidad y Especificidad , Neoplasias Cutáneas/fisiopatología , Células Tumorales Cultivadas
12.
J Korean Acad Nurs ; 43(6): 714-25, 2013 Dec.
Artículo en Coreano | MEDLINE | ID: mdl-24487988

RESUMEN

PURPOSE: This study was done to provide fundamental data for the development of competency reinforcement programs to prevent addictive behavior in adolescents through the construction and examination of an addiction prevention core competency model. METHODS: In this study core competencies for preventing addictive behavior in adolescents through competency modeling were identified, and the addiction prevention core competency model was developed. It was validated methodologically. RESULTS: Competencies for preventing addictive behavior in adolescents as defined by the addiction prevention core competency model are as follows: positive self-worth, self-control skill, time management skill, reality perception skill, risk coping skill, and positive communication with parents and with peers or social group. After construction, concurrent cross validation of the addiction prevention core competency model showed that this model was appropriate. CONCLUSION: The study results indicate that the addiction prevention core competency model for the prevention of addictive behavior in adolescents through competency modeling can be used as a foundation for an integral approach to enhance adolescent is used as an adjective and prevent addictive behavior. This approach can be a school-centered, cost-efficient strategy which not only reduces addictive behavior in adolescents, but also improves the quality of their resources.


Asunto(s)
Conducta Adictiva/prevención & control , Adaptación Psicológica , Adolescente , Relaciones Familiares , Femenino , Humanos , Masculino , Modelos Psicológicos , Psicología del Adolescente , Autoimagen , Encuestas y Cuestionarios
13.
Cell Stem Cell ; 10(5): 620-34, 2012 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-22560082

RESUMEN

Human pluripotent stem cells (hPSCs) are potential sources of cells for modeling disease and development, drug discovery, and regenerative medicine. However, it is important to identify factors that may impact the utility of hPSCs for these applications. In an unbiased analysis of 205 hPSC and 130 somatic samples, we identified hPSC-specific epigenetic and transcriptional aberrations in genes subject to X chromosome inactivation (XCI) and genomic imprinting, which were not corrected during directed differentiation. We also found that specific tissue types were distinguished by unique patterns of DNA hypomethylation, which were recapitulated by DNA demethylation during in vitro directed differentiation. Our results suggest that verification of baseline epigenetic status is critical for hPSC-based disease models in which the observed phenotype depends on proper XCI or imprinting and that tissue-specific DNA methylation patterns can be accurately modeled during directed differentiation of hPSCs, even in the presence of variations in XCI or imprinting.


Asunto(s)
Variación Genética , Células Madre Pluripotentes/fisiología , Diferenciación Celular , Células Cultivadas , Aberraciones Cromosómicas , Cromosomas Humanos X , Metilación de ADN , Impresión Genómica , Humanos , Especificidad de Órganos , Recurrencia , Nicho de Células Madre , Inactivación del Cromosoma X
14.
J Korean Acad Nurs ; 42(7): 957-64, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23377591

RESUMEN

PURPOSE: This study was conducted to develop a gambling addictive behavior scale for adolescents. METHODS: The process involved construction of a conceptual framework, initial item search, verification of content validity, selection of secondary items, and extraction of final items. The participants were 299 adolescents from two middle schools and four high schools. Item analysis, factor analysis, criterion validity, internal consistency, and ROC curve were used to analyze the data. RESULTS: For the final scale, 25 items were selected, and categorized into 4 factors which accounted for 54.9% of the total variance. The factors were labeled as loss of control, life dysfunction from gambling addiction, gambling experience, and social dysfunction from problem gambling. The scores for the scale were significantly correlated with addictive personality, irrational gambling belief, and adolescent's gambling addictive behavior. Cronbach's alpha coefficient for the 25 items was .94. Scale scores identified adolescents as being in a problem gambling group, a non-problem gambling group, and a non-gambling group by the ROC curve. CONCLUSION: The above findings indicate that the gambling addictive behavior scale has good validity and reliability and can be used with adolescents in Korea.


Asunto(s)
Conducta Adictiva/psicología , Juego de Azar , Adolescente , Área Bajo la Curva , Análisis Factorial , Femenino , Humanos , Masculino , Curva ROC , República de Corea , Autoimagen
15.
Regen Med ; 6(6): 689-99, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22050521

RESUMEN

AIMS: Dental tissue has been the focus of attention as an easily accessible postnatal tissue source of high-quality stem cells. Since the first report on the dental pulp stem cells (DPSCs) from permanent third molar teeth, stem cells from human exfoliated deciduous teeth (SHED) were identified as a population distinct from DPSCs. In this study, we compared DPSCs from supernumerary teeth and SHED in three age- and sex-matched patients. PATIENTS & METHODS: Dental samples were obtained from the three patients, who were 6 years old and male, with the parental consent of the three donors, and then isolated cells from dental pulp for comparative analysis between supernumerary DPSCs and SHED. RESULTS: Colony-forming unit fibroblast levels and the proliferation rate of supernumerary DPSCs were slightly lower than that of SHED. The expression of cell surface antigens in supernumerary DPSCs and SHED were almost identical. Cells were mainly expressing endogenous mesodermal and ectodermal lineage markers. Differentiation capacity to osteogenic, adipogenic and chondrogenic lineage was similar in the SHED and supernumerary DPSCs. Migration assay revealed that both supernumerary DPSCs and SHED rapidly migrated toward wounded areas. Supernumerary DPSCs were altered in cell growth after storage for 2 years. Specially, the population doubling time of supernumerary DPSCs increased while that of SHED remained nearly unchanged. CONCLUSION: Both supernumerary teeth and deciduous teeth share many characteristics, such as highly proliferative clonogenic cells with a similar immunophenotype to that of mesenchymal stem cells, although they are inferior to SHED for long-term banking. Our findings suggest that supernumerary teeth are also easily accessible and noninvasive sources of postnatal stem cells with multipotency and regenerative capacity.


Asunto(s)
Células Madre Mesenquimatosas/citología , Exfoliación Dental/patología , Diente Primario/patología , Diente Supernumerario/patología , Diferenciación Celular , Proliferación Celular , Separación Celular , Células Cultivadas , Niño , Células Clonales , Análisis Citogenético , Pulpa Dental/citología , Humanos , Inmunofenotipificación , Incisivo/citología , Masculino , Cicatrización de Heridas
16.
Biomaterials ; 32(34): 8816-29, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21911256

RESUMEN

The physical factors of cell-culture environment have received little attention despite their anticipated significant role in human embryonic stem cell (hESC) culture optimization. Here we show that hESC culture conditions can be optimized by utilizing polyethylene terephthalate (PET) membranes whose defined pore densities (PDs) determine membrane surface hardness. The PET membranes with 1-4 × 10(6) pores/cm(2) (0.291-0.345 GPa) supported the adherence and survival of hESCs without matrix coating. Furthermore, PET membrane with 4 × 10(6) pores/cm(2) (0.345 GPa) supported optimal hESC self renewal as well as by the increase in cell proliferation. The expression level and activity of Rho-associated kinase (ROCK) were specifically down-regulated in hESCs cultured on the optimal PET membrane. We suggest that PET membranes of a defined PD/hardness provide an excellent culture substrate for the maintenance of uniform and undifferentiated hESCs.


Asunto(s)
Técnicas de Cultivo de Célula/instrumentación , Células Madre Embrionarias/citología , Membranas Artificiales , Tereftalatos Polietilenos/química , Diferenciación Celular , Proliferación Celular , Regulación hacia Abajo , Células Madre Embrionarias/metabolismo , Dureza , Humanos , Porosidad , Proteínas de Unión al GTP rho/genética
17.
J Korean Acad Nurs ; 41(3): 364-73, 2011 Jun.
Artículo en Coreano | MEDLINE | ID: mdl-21804345

RESUMEN

PURPOSE: In this study the fitness of a path model for the relationship among biological risk disposition, sociocultural risk factors, self-control, parent-adolescent communication, and risk behavior in adolescents was examined. METHODS: The participants were 387 adolescents. The data were analyzed with the PASW 18.0 and AMOS 18.0 programs. RESULTS: Sociocultural risk factors, self-control, and parent-adolescent communication showed a direct effect on risk behavior for adolescents, while biological risk disposition and sociocultural risk factor showed an indirect effect on risk behavior for adolescents. The modified path model of adolescents' risk behavior was showed a good fit with the model (χ2/df=2.37, GFI=.95, AGFI=.92, RMSEA=.06 [.05

Asunto(s)
Conducta del Adolescente/psicología , Modelos Psicológicos , Asunción de Riesgos , Adolescente , Comunicación , Femenino , Humanos , Masculino , Relaciones Padres-Hijo , Autoimagen , Encuestas y Cuestionarios
18.
J Korean Acad Nurs ; 41(2): 204-13, 2011 Apr.
Artículo en Coreano | MEDLINE | ID: mdl-21551992

RESUMEN

PURPOSE: This study was done to identify fundamental data on competency reinforcement programs to prevent adolescent risk behavior by developing and examining a competency model. METHODS: In this study, competences on prevention of adolescent risk behavior were identified through competency modeling, and a competency model was developed and tested for validity. RESULTS: Competences for prevention of adolescent risk behavior defined by the competency model included the following: self-control, positive mutual understanding between parents and adolescents, and positive connectedness with peer group. Validation of the competency model showed the model to be appropriate. CONCLUSION: The competency model for prevention of adolescent risk behavior through competency modeling is expected to be the foundation of an integral approach to enhance competency in adolescents and prevent adolescent risk behavior. This kind of approach can be a school-centered, cost-efficient strategy, which not only reduces adolescent risk behavior but also improves quality of adolescent resources.


Asunto(s)
Conducta del Adolescente , Modelos Teóricos , Asunción de Riesgos , Adolescente , Relaciones Familiares , Humanos , Entrevistas como Asunto , Grupo Paritario , Psicología del Adolescente , Proyectos de Investigación , Autoimagen
19.
Cell Stem Cell ; 8(1): 106-18, 2011 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-21211785

RESUMEN

Genomic stability is critical for the clinical use of human embryonic and induced pluripotent stem cells. We performed high-resolution SNP (single-nucleotide polymorphism) analysis on 186 pluripotent and 119 nonpluripotent samples. We report a higher frequency of subchromosomal copy number variations in pluripotent samples compared to nonpluripotent samples, with variations enriched in specific genomic regions. The distribution of these variations differed between hESCs and hiPSCs, characterized by large numbers of duplications found in a few hESC samples and moderate numbers of deletions distributed across many hiPSC samples. For hiPSCs, the reprogramming process was associated with deletions of tumor-suppressor genes, whereas time in culture was associated with duplications of oncogenic genes. We also observed duplications that arose during a differentiation protocol. Our results illustrate the dynamic nature of genomic abnormalities in pluripotent stem cells and the need for frequent genomic monitoring to assure phenotypic stability and clinical safety.


Asunto(s)
Proliferación Celular , Reprogramación Celular , Células Madre Embrionarias/citología , Dosificación de Gen , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes/citología , Diferenciación Celular , Células Cultivadas , Células Madre Embrionarias/metabolismo , Genoma Humano , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Fenotipo , Células Madre Pluripotentes/metabolismo
20.
Genes Dev ; 24(13): 1345-50, 2010 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-20595230

RESUMEN

In Escherichia coli, the major nucleoid protein H-NS limits transcription by acting as a repressor or transcriptional silencer, presumably by its ability to close the looped chromosome domains in the nucleoid through DNA-protein-DNA bridging. Here, we demonstrate the direct involvement of H-NS as a positive factor stimulating translation of the malT mRNA. In vitro studies showed that H-NS facilitates a repositioning of the 30S preinitiation complex on the malT mRNA. H-NS stimulation of translation depended on the AU-rich -35 to -40 region of the mRNA. Several additional examples were found demonstrating a novel function for H-NS in translation of genes with suboptimal ribosome-binding sequences.


Asunto(s)
Proteínas de Escherichia coli/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Fimbrias/metabolismo , Biosíntesis de Proteínas , Ribosomas/metabolismo , Activación Transcripcional , Sitios de Unión , Unión Proteica
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA