Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
Más filtros













Base de datos
Intervalo de año de publicación
1.
Adv Med Sci ; 69(1): 1-7, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38096771

RESUMEN

PURPOSE: Bronchial hyperresponsiveness (BHR), a hallmark of bronchial asthma, is typically diagnosed through a methacholine inhalation test followed by spirometry, known as the methacholine challenge test (MCT). While spirometry relies on proper patients' cooperation and precise execution of forced breathing maneuvers, we conducted a comparative analysis with the portable nanomaterial-based sensing device, SenseGuard™, to non-intrusively assess tidal breathing parameters. MATERIALS AND METHODS: In this prospective study, 37 adult participants with suspected asthma underwent sequential spirometry and SenseGuard™ measurements after inhaling increasing methacholine doses. RESULTS: Among the 37 participants, 18 were MCT responders, 17 were non-responders and 2 were excluded due to uninterpretable data. The MCT responders exhibited a significant lung function difference when comparing the change from baseline to maximum response. This was evident through a notable decrease in forced expiratory volume in 1 â€‹s (FEV1) levels in spirometry, as well as in prominent changes in tidal breathing parameters as assessed by SenseGuard™, including the expiratory pause time (Trest) to total breath time (Ttot) ratio, and the expiratory time (Tex) to Ttot ratio. Notably, the ratios Trest/Ttot (∗p â€‹= â€‹0.02), Tex/Ttot (∗p â€‹= â€‹0.002), and inspiratory time (Tin) to Tex (∗p â€‹= â€‹0.04) identified MCT responders distinctly, corresponding to spirometry (∗p â€‹< â€‹0.0001). CONCLUSIONS: This study demonstrates that tidal breathing assessment using SenseGuard™ device reliably detects clinically relevant changes of respiratory parameter during the MCT. It effectively distinguishes between responders and non-responders, with strong agreement to conventional spirometry-measured FEV1. This technology holds promise for monitoring clinical respiratory changes in bronchial asthma patients pending further studies.


Asunto(s)
Pruebas de Provocación Bronquial , Cloruro de Metacolina , Humanos , Masculino , Femenino , Adulto , Pruebas de Provocación Bronquial/métodos , Pruebas de Provocación Bronquial/instrumentación , Estudios Prospectivos , Espirometría/instrumentación , Espirometría/métodos , Persona de Mediana Edad , Asma/diagnóstico , Asma/fisiopatología , Volumen de Ventilación Pulmonar , Adulto Joven , Hiperreactividad Bronquial/diagnóstico , Hiperreactividad Bronquial/fisiopatología
2.
Adv Med Sci ; 68(2): 176-185, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37146372

RESUMEN

PURPOSE: Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is a complication of COPD that typically necessitates intensified treatment and hospitalization. It is linked to higher morbidity, mortality and healthcare spending. Assessment of therapy response for AECOPD is difficult due to the variability of symptoms and limitations in current measures. Hence, there is a need for new biomarkers to aid in the management of AECOPD in acute care settings. MATERIALS AND METHODS: Fifteen hospitalized AECOPD patients (GOLD 3-4) were enrolled in this study. Treatment response was assessed daily through clinical evaluations and by monitoring tidal breathing biomarkers (respiratory rate [RR], expiratory time [Tex], inspiratory time [Tin], expiratory pause [Trst], total breath time [Ttot]), using a novel, wearable nanosensor-based device (SenseGuard™). RESULTS: Patients who showed significant clinical improvement had substantial changes in ΔTex/Ttot (+14%), ΔTrst/Ttot (-18%), and ΔTin/Tex (+0.09), whereas patients who showed mild or no clinical improvement had smaller changes (+5%, +3%, and -0.03, respectively). Linear regression between change in physician's assessment score and the median change in tidal breathing parameters was significant for Tin/Tex (R2 â€‹= â€‹0.449, ∗p â€‹= â€‹0.017), Tex/Ttot (R2 â€‹= â€‹0.556, ∗p â€‹= â€‹0.005) and Trst/Ttot (R2 â€‹= â€‹0.446, ∗p â€‹= â€‹0.018), while no significant regression was observed for RR, Tin/(Trst â€‹+ â€‹Tex) and Tin/Ttot. CONCLUSIONS: Our study demonstrates the potential of the SenseGuard™ to monitor treatment response in AECOPD patients by measuring changes in tidal breathing biomarkers, which were shown to be associated with significant changes in the patients' respiratory condition as evaluated by physicians. However, further large-scale clinical studies are needed to confirm these findings.


Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica , Humanos , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Espiración , Hospitalización , Progresión de la Enfermedad , Biomarcadores
3.
Pain Res Manag ; 2021: 2542010, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34055117

RESUMEN

Background: Acute postoperative pain delays recovery and increases morbidity and mortality. Opioid therapy is effective but is accompanied by adverse reactions. Patient-controlled analgesia (PCA) enables self-administration of analgesics. Oral-PCA is a safe and beneficial alternative to intravenous (IV) PCA. We have developed a novel Oral-PCA device, which enables self-administration of solid pills to the patient's mouth. This is a retrospective study comparing the effectiveness and usability of this novel Oral-PCA with those of IV-PCA. Methods: Medical records of patients who received PCA following gynecology and orthopedic surgeries were analyzed. The control cohort (n = 61) received oxycodone by IV-PCA. The test cohort (n = 44) received oxycodone by Oral-PCA via the PCoA Acute device. Outcome measures include the Numeric Rating Scale (NRS) score at rest and movement, side effects, technical difficulties, bolus dose administered, and bolus dose requested. Results: Patient demographics, initial NRS, and PCA duration were comparable between cohorts. NRS reduction in rest and movement was stronger in the Oral-PCA cohort (rest: 1.61 and 2.27, P = 0.077; movement: 2.05 and 2.84, P = 0.039), indicating better pain control and mobility for Oral-PCA. Side effect rates were comparable between cohorts (9% and 11% of patients who experienced side effects, P = 1.000). The rate of technological difficulties was higher in the Oral-PCoA cohort (19.7% and 36.4%, P = 0.056). The mean total bolus dose administered to patients was comparable in both cohorts (18.32 mg and 21.14 mg oxycodone, P = 0.270). However, the mean total boluses requested by patients during lockout intervals were lower in the Oral-PCA cohort (12.8 mg and 6.82 mg oxycodone, P = 0.004), indicating better pain control. Conclusions: Oral-PCA by using PCoA® Acute provides pain control and usability which is noninferior to the IV-PCA, as well as superior to pain reduction in rest and movement. These results, along with the noninvasiveness, medication flexibility, and reduced cost, suggest the potential of Oral-PCA, by using PCoA Acute, to replace IV-PCA for postoperative analgesia.


Asunto(s)
Administración Intravenosa , Administración Oral , Analgesia Controlada por el Paciente/instrumentación , Analgésicos Opioides/administración & dosificación , Oxicodona/administración & dosificación , Manejo del Dolor/instrumentación , Dolor Postoperatorio/tratamiento farmacológico , Administración Intravenosa/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
4.
JMIR Hum Factors ; 5(4): e10128, 2018 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-30478020

RESUMEN

BACKGROUND: Medication nonadherence is a major problem in health care, imposing poor clinical outcomes and a heavy financial burden on all stakeholders. Current methods of medication adherence assessment are severely limited: they are applied only periodically, do not relate to actual pill intake, and suffer from patient bias due to errors, misunderstanding, or intentional nonadherence. ReX is an innovative medication management system designed to address poor patient adherence and enhance patient engagement with their therapy. ReX controls and tracks pills from the point of packaging right through to the patient's mouth. ReX generates robust, real-time adherence data. The system enables patients to report outcomes, complete surveys, and receive messages and instructions. ReX includes a reusable drug dispensing unit, disposable cassette containing pills, and a cloud-based data portal. OBJECTIVE: We aimed to evaluate ReX feasibility by human factor studies including evaluation of ReX safety; ReX acceptance and usability; and ReX efficacy of providing pills according to a preprogrammed dose regimen, managing reminders and adherence data, and enhancing the adherence rate compared with the standard of care. METHODS: The ReX system was evaluated in 2 human factor, nonclinical feasibility studies. Human subjects used ReX for the administration of pill-shaped Tic Tac sweets. The initial study evaluated ReX use and pill intake administration; second was a self-controlled, 4-day home-use study. All subjects took pills at home, according to a preprogrammed dose regimen, for 4 days each via the device (ReX test) or from standard packaging (control test). The adherence rate (percent of pills taken) was measured by the study subject's report, remaining pills count, and ReX records (in the ReX test). ReX safety and usability were evaluated by a questionnaire filled out by the subject. RESULTS: The initial feasibility study evaluated usability and acceptance of the ReX novel approach to pill dispensing. All subjects successfully managed 2 pill intakes. The ReX device was rated as easy to use by 81% (48/59) of subjects. The 4-day home-use study evaluated the safety, efficacy, and usability of the ReX system. No adverse event occurred; no pill overdose or pill malformation was reported. The overall adherence rate in the ReX test was 97.6% compared with 76.3% in the control test (P<.001). Real-time, personalized reminders provided in the event of a delay in pill intake contributed to 18.0% of doses taken during the ReX test. The ReX system was found easy to use by 87% (35/40) of subjects; 90% (36/40) felt comfortable using it for their medication. CONCLUSIONS: ReX's novel "tracking to the mouth" technology was found usable and accepted by subjects. The assessment of adherence rates was reliable; adherence of subjects to the dose regimen was significantly enhanced when using ReX compared with the standard of care.

5.
Pain Res Manag ; 2017: 7962135, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29093632

RESUMEN

Background: Acute postoperative pain delays recovery and increases morbidity and mortality. Traditional administration of postoperative analgesics by nurses is often inefficient. The present study evaluated the safety, efficacy, and usability of a novel, patient-controlled analgesic dispenser, the PCoA Acute. Methods: A controlled pilot study was conducted at three medical centers. Patients scheduled for elective surgery were enrolled into two groups, both taking oral analgesics: a control group (n = 43), opioids dispensed by nurses, and a test group (n = 27), opioids dispensed via the PCoA Acute. Pill intake data were recorded. Pain ratings at rest and during movement were surveyed. Results: No severe adverse events were recorded. Average pill intake time was reduced from 8 : 58 minutes in the control group to 1 : 17 minutes in the test group (P value < 0.05). The test group took 67% more pills than the control group, indicating enhanced compliance. Pain scores were significantly lower for patients in the test group (P value < 0.05). Over 90% of PCoA Acute users were satisfied with its use. Conclusions: The study confirmed that PCoA Acute is safe and effective. It is well accepted by patients and medical staff. Its use can optimize pain medication administration.


Asunto(s)
Analgesia Controlada por el Paciente/métodos , Dimensión del Dolor/instrumentación , Dolor Postoperatorio/tratamiento farmacológico , Dolor Agudo/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Factibilidad , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor/métodos , Proyectos Piloto , Estadísticas no Paramétricas , Resultado del Tratamiento , Adulto Joven
6.
OMICS ; 20(3): 139-51, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26983021

RESUMEN

Postgenomics data are produced in large volumes by life sciences and clinical applications of novel omics diagnostics and therapeutics for precision medicine. To move from "data-to-knowledge-to-innovation," a crucial missing step in the current era is, however, our limited understanding of biological and clinical contexts associated with data. Prominent among the emerging remedies to this challenge are the gene set enrichment tools. This study reports on GeneAnalytics™ ( geneanalytics.genecards.org ), a comprehensive and easy-to-apply gene set analysis tool for rapid contextualization of expression patterns and functional signatures embedded in the postgenomics Big Data domains, such as Next Generation Sequencing (NGS), RNAseq, and microarray experiments. GeneAnalytics' differentiating features include in-depth evidence-based scoring algorithms, an intuitive user interface and proprietary unified data. GeneAnalytics employs the LifeMap Science's GeneCards suite, including the GeneCards®--the human gene database; the MalaCards-the human diseases database; and the PathCards--the biological pathways database. Expression-based analysis in GeneAnalytics relies on the LifeMap Discovery®--the embryonic development and stem cells database, which includes manually curated expression data for normal and diseased tissues, enabling advanced matching algorithm for gene-tissue association. This assists in evaluating differentiation protocols and discovering biomarkers for tissues and cells. Results are directly linked to gene, disease, or cell "cards" in the GeneCards suite. Future developments aim to enhance the GeneAnalytics algorithm as well as visualizations, employing varied graphical display items. Such attributes make GeneAnalytics a broadly applicable postgenomics data analyses and interpretation tool for translation of data to knowledge-based innovation in various Big Data fields such as precision medicine, ecogenomics, nutrigenomics, pharmacogenomics, vaccinomics, and others yet to emerge on the postgenomics horizon.


Asunto(s)
Biología Computacional/métodos , Redes Reguladoras de Genes , Genoma Humano , Secuenciación de Nucleótidos de Alto Rendimiento/estadística & datos numéricos , Análisis por Micromatrices/estadística & datos numéricos , Programas Informáticos , Algoritmos , Minería de Datos , Bases de Datos Factuales , Bases de Datos Genéticas , Humanos , Redes y Vías Metabólicas/genética
7.
Regen Med ; 9(5): 649-72, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25372080

RESUMEN

Cell therapies aim to repair the mechanisms underlying disease initiation and progression, achieved through trophic effect or by cell replacement. Multiple cell types can be utilized in such therapies, including stem, progenitor or primary cells. This review covers the current state of cell therapies designed for the prominent disorders, including cardiovascular, neurological (Parkinson's disease, amyotrophic lateral sclerosis, stroke, spinal cord injury), autoimmune (Type 1 diabetes, multiple sclerosis, Crohn's disease), ophthalmologic, renal, liver and skeletal (osteoarthritis) diseases. Various cell therapies have reached advanced clinical trial phases with potential marketing approvals in the near future, many of which are based on mesenchymal stem cells. Advances in pluripotent stem cell research hold great promise for regenerative medicine. The information presented in this review is based on the analysis of the cell therapy collection detailed in LifeMap Discovery(®) (LifeMap Sciences Inc., USA) the database of embryonic development, stem cell research and regenerative medicine.


Asunto(s)
Tratamiento Basado en Trasplante de Células y Tejidos/tendencias , Medicina Regenerativa/tendencias , Trasplante de Células Madre , Enfermedades Autoinmunes/terapia , Humanos , Enfermedades Renales/terapia , Hepatopatías/terapia , Enfermedades del Sistema Nervioso/terapia , Osteoartritis/terapia , Traumatismos de la Médula Espinal/terapia , Enfermedades Vasculares/terapia
8.
Tissue Eng Part A ; 20(19-20): 2756-67, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25185111

RESUMEN

Extracellular matrix (ECM) has been utilized as a biological scaffold for tissue engineering applications in a variety of body systems, due to its bioactivity and biocompatibility. In the current study we developed a modified protocol for the efficient and reproducible derivation of mesenchymal progenitor cells (MPCs) from human embryonic stem cells as well as human induced pluripotent stem cells (hiPSCs) originating from hair follicle keratinocytes (HFKTs). ECM was produced from these MPCs and characterized in comparison to adipose mesenchymal stem cell ECM, demonstrating robust ECM generation by the excised HFKT-iPSC-MPCs. Exploiting the advantages of electrospinning we generated two types of electrospun biodegradable nanofiber layers (NFLs), fabricated from polycaprolactone (PCL) and poly(lactic-co-glycolic acid) (PLGA), which provide mechanical support for cell seeding and ECM generation. Elucidating the optimized decellularization treatment we were able to generate an available "off-the-shelf" implantable product (NFL-ECM). Using rat subcutaneous transplantation model we demonstrate that this stem-cell-derived construct is biocompatible and biodegradable and holds great potential for tissue regeneration applications.


Asunto(s)
Matriz Extracelular/química , Células Madre Pluripotentes Inducidas/metabolismo , Ácido Láctico/química , Nanofibras/química , Poliésteres/química , Ácido Poliglicólico/química , Medicina Regenerativa , Animales , Células Madre Embrionarias/citología , Células Madre Embrionarias/metabolismo , Folículo Piloso/citología , Folículo Piloso/metabolismo , Humanos , Células Madre Pluripotentes Inducidas/citología , Queratinocitos/citología , Queratinocitos/metabolismo , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones SCID , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas
9.
Stem Cells Dev ; 23(5): 443-56, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-24192045

RESUMEN

Adenosine-to-inosine (A-to-I) RNA editing is a post-transcriptional, site-specific modification process that is catalyzed by Adenosine Deaminase Acting on RNA (ADAR) gene family members. Since ADARs act on double-stranded RNA, most A-to-I editing occurs within repetitive elements, particularly Alu elements, as the result of the inherent property of these sequences to fold and form double strands. ADAR1-mediated A-to-I RNA editing was recently implicated in the regulation of human embryonic stem cells (hESCs). Spontaneous and neuronal differentiation of hESC was shown to result in a decrease in A-to-I editing levels. Knockdown of ADAR1 in hESCs results in an elevation of the expression of differentiation-related genes. In addition, we found that hESCs over-expressing ADAR1 could not be generated. The current study shows that the editing levels of induced pluripotent stem cells (iPSCs) change throughout reprogramming, from a source cell level to a level similar to that of hESCs. Up- or down-regulation of the ADAR1 level in human foreskin fibroblast (HFF) cells before induction of reprogramming results in varied reprogramming efficiencies. Furthermore, HFF-iPSC early clones derived from source cells in which the ADAR1 level was down-regulated lose their iPSC properties shortly after iPSC colony formation and instead exhibit characteristics of cancer cells. Taken together, our results imply a role for ADAR1 in the regulation of pluripotency induction as well as in the maintenance of early iPSC properties.


Asunto(s)
Adenosina Desaminasa/biosíntesis , Diferenciación Celular/genética , Células Madre Embrionarias , Células Madre Pluripotentes Inducidas , Adenosina Desaminasa/genética , Fibroblastos , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Proteínas de Unión al ARN
10.
PLoS One ; 8(7): e66629, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23874394

RESUMEN

LifeMap Discovery™ provides investigators with an integrated database of embryonic development, stem cell biology and regenerative medicine. The hand-curated reconstruction of cell ontology with stem cell biology; including molecular, cellular, anatomical and disease-related information, provides efficient and easy-to-use, searchable research tools. The database collates in vivo and in vitro gene expression and guides translation from in vitro data to the clinical utility, and thus can be utilized as a powerful tool for research and discovery in stem cell biology, developmental biology, disease mechanisms and therapeutic discovery. LifeMap Discovery is freely available to academic nonprofit institutions at http://discovery.lifemapsc.com.


Asunto(s)
Desarrollo Embrionario , Medicina Regenerativa , Animales , Diferenciación Celular , Minería de Datos , Expresión Génica , Humanos , Biosíntesis de Proteínas , Células Madre/citología
11.
PLoS One ; 7(7): e41576, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22859999

RESUMEN

Post-transcriptional events play an important role in human development. The question arises as to whether Adenosine to Inosine RNA editing, catalyzed by the ADAR (Adenosine Deaminase acting on RNA) enzymes, differs in human embryogenesis and in adulthood. We tested the editing of various target genes in coding (FLNA, BLCAP, CYFIP2) and non-coding sequences at their Alu elements (BRCA1, CARD11, RBBP9, MDM4, FNACC), as well as the transcriptional levels of the ADAR1 enzymes. This analysis was performed on five fetal and adult human tissues: brain, heart, liver, kidney, and spleen, as well as on human embryonic stem cells (hESCs), which represent the blastocyst stage in early human development. Our results show substantially greater editing activity for most adult tissue samples relative to fetal ones, in six of the eight genes tested. To test the effect of reduced A-to-I RNA editing activity in early human development we used human embryonic stem cells (hESCs) as a model and tried to generate hESC clones that overexpress the ADAR1-p110 isoform. We were unable to achieve overexpression of ADAR1-p110 by either transfection or lentiviral infection, though we easily generated hESC clones that expressed the GFP transgene and overexpressed ADAR1-p110 in 293T cells and in primary human foreskin fibroblast (HFF) cells. Moreover, in contrast to the expected overexpression of ADAR1-p110 protein following its introduction into hESCs, the expression levels of this protein decreased dramatically 24-48 hr post infection. Similar results were obtained when we tried to overexpress ADAR1-p110 in pluripotent embryonal carcinoma cells. This suggests that ADAR1 protein is substantially regulated in undifferentiated pluripotent hESCs. Overall, our data suggest that A-to-I RNA editing plays a critical role during early human development.


Asunto(s)
Desarrollo Embrionario , Edición de ARN , ARN Mensajero/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Adenosina/genética , Adenosina/metabolismo , Adenosina Desaminasa/genética , Adenosina Desaminasa/metabolismo , Elementos Alu , Proteína BRCA1/genética , Proteínas Adaptadoras de Señalización CARD/genética , Proteínas de Ciclo Celular/genética , Células Cultivadas , Proteínas Contráctiles/genética , Células Madre de Carcinoma Embrionario , Células Madre Embrionarias , Proteína del Grupo de Complementación C de la Anemia de Fanconi/genética , Filaminas , Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Guanilato Ciclasa/genética , Humanos , Inosina/genética , Inosina/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas de Microfilamentos/genética , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Proto-Oncogénicas/genética , ARN Mensajero/genética , Proteínas de Unión al ARN
12.
J Cell Mol Med ; 16(3): 468-82, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22050625

RESUMEN

Sudden cardiac death caused by ventricular arrhythmias is a disastrous event, especially when it occurs in young individuals. Among the five major arrhythmogenic disorders occurring in the absence of a structural heart disease is catecholaminergic polymorphic ventricular tachycardia (CPVT), which is a highly lethal form of inherited arrhythmias. Our study focuses on the autosomal recessive form of the disease caused by the missense mutation D307H in the cardiac calsequestrin gene, CASQ2. Because CASQ2 is a key player in excitation contraction coupling, the derangements in intracellular Ca(2+) handling may cause delayed afterdepolarizations (DADs), which constitute the mechanism underlying CPVT. To investigate catecholamine-induced arrhythmias in the CASQ2 mutated cells, we generated for the first time CPVT-derived induced pluripotent stem cells (iPSCs) by reprogramming fibroblasts from skin biopsies of two patients, and demonstrated that the iPSCs carry the CASQ2 mutation. Next, iPSCs were differentiated to cardiomyocytes (iPSCs-CMs), which expressed the mutant CASQ2 protein. The major findings were that the ß-adrenergic agonist isoproterenol caused in CPVT iPSCs-CMs (but not in the control cardiomyocytes) DADs, oscillatory arrhythmic prepotentials, after-contractions and diastolic [Ca(2+) ](i) rise. Electron microscopy analysis revealed that compared with control iPSCs-CMs, CPVT iPSCs-CMs displayed a more immature phenotype with less organized myofibrils, enlarged sarcoplasmic reticulum cisternae and reduced number of caveolae. In summary, our results demonstrate that the patient-specific mutated cardiomyocytes can be used to study the electrophysiological mechanisms underlying CPVT.


Asunto(s)
Agonistas Adrenérgicos beta/farmacología , Calsecuestrina/genética , Isoproterenol/farmacología , Miocardio/metabolismo , Miocitos Cardíacos/metabolismo , Taquicardia Ventricular/patología , Adulto , Calcio/metabolismo , Señalización del Calcio , Calsecuestrina/metabolismo , Diferenciación Celular , Niño , Acoplamiento Excitación-Contracción , Femenino , Fibroblastos/metabolismo , Fibroblastos/patología , Genes Recesivos , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Células Madre Pluripotentes Inducidas/patología , Masculino , Potenciales de la Membrana , Mutación Missense , Miocardio/patología , Miocitos Cardíacos/patología , Taquicardia Ventricular/genética , Taquicardia Ventricular/metabolismo
13.
J Cell Mol Med ; 15(1): 38-51, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20041972

RESUMEN

In view of the therapeutic potential of cardiomyocytes derived from induced pluripotent stem (iPS) cells (iPS-derived cardiomyocytes), in the present study we investigated in iPS-derived cardiomyocytes, the functional properties related to [Ca(2+) ](i) handling and contraction, the contribution of the sarcoplasmic reticulum (SR) Ca(2+) release to contraction and the b-adrenergic inotropic responsiveness. The two iPS clones investigated here were generated through infection of human foreskin fibroblasts (HFF) with retroviruses containing the four human genes: OCT4, Sox2, Klf4 and C-Myc. Our major findings showed that iPS-derived cardiomyocytes: (i) express cardiac specific RNA and proteins; (ii) exhibit negative force-frequency relations and mild (compared to adult) post-rest potentiation; (iii) respond to ryanodine and caffeine, albeit less than adult cardiomyocytes, and express the SR-Ca(2+) handling proteins ryanodine receptor and calsequestrin. Hence, this study demonstrates that in our cardiomyocytes clones differentiated from HFF-derived iPS, the functional properties related to excitation-contraction coupling, resemble in part those of adult cardiomyocytes.


Asunto(s)
Células Madre Pluripotentes Inducidas/citología , Miocitos Cardíacos/metabolismo , Animales , Cafeína/farmacología , Calcio/metabolismo , Calsecuestrina/genética , Calsecuestrina/metabolismo , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Fibroblastos/metabolismo , Técnica del Anticuerpo Fluorescente , Prepucio/citología , Expresión Génica , Humanos , Factor 4 Similar a Kruppel , Factores de Transcripción de Tipo Kruppel/genética , Masculino , Ratones , Ratones SCID , Contracción Miocárdica/efectos de los fármacos , Miocitos Cardíacos/efectos de los fármacos , Factor 3 de Transcripción de Unión a Octámeros/genética , Proteínas Proto-Oncogénicas c-myc/genética , ARN Mensajero/metabolismo , Rianodina/farmacología , Canal Liberador de Calcio Receptor de Rianodina/genética , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Factores de Transcripción SOXB1/genética , Retículo Sarcoplasmático/metabolismo , Teratoma/metabolismo , Teratoma/patología
14.
Cell Reprogram ; 12(6): 665-78, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20964482

RESUMEN

Induced pluripotent stem cells (iPSCs) represent an ideal cell source for future cell therapy and regenerative medicine. However, most iPSC lines described to date have been isolated from skin fibroblasts or other cell types that require harvesting by surgical intervention. Because it is desirable to avoid such intervention, an alternative cell source that can be readily and noninvasively isolated from patients and efficiently reprogrammed, is required. Here we describe a detailed and reproducible method to derive iPSCs from plucked human hair follicle keratinocytes (HFKTs). HFKTs were isolated from single plucked hair, then expanded and reprogrammed by a single polycistronic excisable lentiviral vector. The reprogrammed HFKTs were found to be very sensitive to human embryonic stem cell (hESC) growth conditions, generating a built-in selection with easily obtainable and very stable iPSCs. All emerging colonies were true iPSCs, with characteristics typical of human embryonic stem cells, differentiated into derivatives of all three germ layers in vitro and in vivo. Spontenaeouly differentiating functional cardiomyocytes (CMs) were successfully derived and characterized from these HFKT-iPSCs. The contracting CMs exhibited well-coordinated intracellular Ca²+ transients and contractions that were readily responsive to ß-adrenergic stimulation with isoproterenol. The introduction of Cre-recombinase to HFKT-iPSC clones was able to successfully excise the integrated vector and generate transgene-free HFKT-iPSC clone that could be better differentiated into contracting CMs, thereby revealing the desired cells for modeling human diseases. Thus, HFKTs are easily obtainable, and highly reprogrammed human cell source for all iPSC applications.


Asunto(s)
Diferenciación Celular/fisiología , Folículo Piloso/química , Corazón/embriología , Queratinocitos/fisiología , Lentivirus/metabolismo , Miocardio/citología , Técnicas de Cultivo de Célula/métodos , Células Cultivadas , Humanos , Queratinocitos/citología , Lentivirus/genética , Técnicas de Placa-Clamp , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/fisiología
15.
PLoS One ; 5(6): e11173, 2010 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-20574523

RESUMEN

Adenosine to Inosine (A-to-I) RNA editing is a site-specific modification of RNA transcripts, catalyzed by members of the ADAR (Adenosine Deaminase Acting on RNA) protein family. RNA editing occurs in human RNA in thousands of different sites. Some of the sites are located in protein-coding regions but the majority is found in non-coding regions, such as 3'UTRs, 5'UTRs and introns - mainly in Alu elements. While editing is found in all tissues, the highest levels of editing are found in the brain. It was shown that editing levels within protein-coding regions are increased during embryogenesis and after birth and that RNA editing is crucial for organism viability as well as for normal development. In this study we characterized the A-to-I RNA editing phenomenon during neuronal and spontaneous differentiation of human embryonic stem cells (hESCs). We identified high editing levels of Alu repetitive elements in hESCs and demonstrated a global decrease in editing levels of non-coding Alu sites when hESCs are differentiating, particularly into the neural lineage. Using RNA interference, we showed that the elevated editing levels of Alu elements in undifferentiated hESCs are highly dependent on ADAR1. DNA microarray analysis showed that ADAR1 knockdown has a global effect on gene expression in hESCs and leads to a significant increase in RNA expression levels of genes involved in differentiation and development processes, including neurogenesis. Taken together, we speculate that A-to-I editing of Alu sequences plays a role in the regulation of hESC early differentiation decisions.


Asunto(s)
Adenosina/metabolismo , Elementos Alu/genética , Células Madre Embrionarias/citología , Células Madre Embrionarias/metabolismo , Inosina/metabolismo , Edición de ARN , Adenosina Desaminasa/deficiencia , Adenosina Desaminasa/genética , Adenosina Desaminasa/metabolismo , Animales , Diferenciación Celular , Regulación Enzimológica de la Expresión Génica/genética , Silenciador del Gen , Humanos , Ratones , Neuronas/citología , Sistemas de Lectura Abierta/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas de Unión al ARN
16.
Infect Immun ; 70(10): 5579-88, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12228285

RESUMEN

The host interferon (IFN) system plays an important role in protection against microbial infections. Salmonella enterica serovar Typhimurium is highly virulent in the mouse model, whereas mutants that lack DNA adenine methylase (Dam(-)) are highly attenuated and elicit fully protective immune responses against murine typhoid fever. We examined the expression of IFN-responsive genes in several mouse tissues following infection with Dam(+) or Dam(-) Salmonella. Infection of mice with Dam(+) Salmonella resulted in the induction of host genes known to be indicators of IFN bioactivity and regulated by either IFN-alpha/beta (Mx1) or IFN-gamma (class II transactivator protein [CIITA] and inducible nitric oxide synthase [iNOS]) or by both IFN-alpha/beta and IFN-gamma (RNA-specific adenosine deaminase [ADAR1] and RNA-dependent protein kinase [PKR]) in a tissue-specific manner compared to uninfected animals. Since the Mx1 promoter is IFN-alpha/beta specific and the Mx1 gene is not inducible directly by IFN-gamma, these data suggest a role of IFN-alpha/beta in the host response to Salmonella infection. Mice infected with Dam(-) Salmonella showed reduced expression of the same set of IFN-stimulated genes (ISGs) as that observed after infection with wild-type Salmonella. The reduced capacity to induce ISGs persisted in Dam(-)-vaccinated mice after challenge with the virulent (Dam(+)) strain. Finally, although no Dam(-) organisms were recovered from the liver or spleen after oral infection of mice, ADAR, PKR, Mx, and CIITA expression levels were elevated in these tissues relative to those in uninfected mice, suggestive of the distant action of a signaling molecule(s) in the activation of ISG expression.


Asunto(s)
Interferones/farmacología , Proteínas Nucleares , Salmonella typhimurium/genética , Salmonella typhimurium/patogenicidad , Metiltransferasa de ADN de Sitio Específico (Adenina Especifica)/genética , Adenosina Desaminasa/genética , Empalme Alternativo , Animales , Secuencia de Bases , ADN/genética , Femenino , Expresión Génica/efectos de los fármacos , Interferón Tipo I/farmacología , Interferón gamma/farmacología , Ratones , Ratones Endogámicos BALB C , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas de Unión al ARN , Proteínas Recombinantes , Salmonelosis Animal/etiología , Salmonelosis Animal/genética , Salmonelosis Animal/inmunología , Vacunas contra la Salmonella/farmacología , Salmonella typhimurium/enzimología , Metiltransferasa de ADN de Sitio Específico (Adenina Especifica)/fisiología , Distribución Tisular , Transactivadores/genética , Virulencia/genética , Virulencia/fisiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA