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1.
Environ Dev Sustain ; 24(5): 6834-6859, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34393620

RESUMEN

Sustainable development is not just possible with regard to the environmental and economic dimensions, and social issues are also important in achieving sustainable development. Social sustainability, as one of the dimensions of sustainable development, has been considered by policy makers and managers. Social sustainability and business ethics in the organization are affected by social and behavioral interactions of individuals. Blockchain technology, as a disruptive technology, leads to a peer-to-peer and decentralized network management using distributed architecture. Blockchain technology can affect the way information is exchanged and creates transparency in the organization. Therefore, the purpose of this study is to evaluate the impact of blockchain technology on business ethics and social sustainability in the organization. In the first part of the research, a conceptual model is extracted using previous studies. In the second part, the relationship between model variables among 411 managers of small and medium enterprises (SMEs) active in the Middle East region is evaluated according to the importance of sustainability in this region. Structural equation model and SmartPLS software have been used for data analysis. The research findings show that the use of blockchain technology has a direct impact on business ethics, corporate governance and social sustainability due to the creation of a decentralized system, information transparency and traceability. Also, business ethics and corporate governance have an impact on achieving social sustainability.

2.
Stem Cells Dev ; 23(11): 1275-84, 2014 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-24512547

RESUMEN

In mammals, the permanence of many forms of hearing loss is the result of the inner ear's inability to replace lost sensory hair cells. Here, we apply a differentiation strategy to guide human embryonic stem cells (hESCs) into cells of the otic lineage using chemically defined attached-substrate conditions. The generation of human otic progenitor cells was dependent on fibroblast growth factor (FGF) signaling, and protracted culture led to the upregulation of markers indicative of differentiated inner ear sensory epithelia. Using a transgenic ESC reporter line based on a murine Atoh1 enhancer, we show that differentiated hair cell-like cells express multiple hair cell markers simultaneously. Hair cell-like cells displayed protrusions reminiscent of stereociliary bundles, but failed to fully mature into cells with typical hair cell cytoarchitecture. We conclude that optimized defined conditions can be used in vitro to attain otic progenitor specification and sensory cell differentiation.


Asunto(s)
Diferenciación Celular , Células Madre Embrionarias/fisiología , Células Ciliadas Auditivas Internas/fisiología , Biomarcadores/metabolismo , Técnicas de Cultivo de Célula , Diferenciación Celular/genética , Células Cultivadas , Oído Interno/citología , Oído Interno/metabolismo , Células Madre Embrionarias/citología , Epitelio/metabolismo , Regulación de la Expresión Génica , Células Ciliadas Auditivas Internas/citología , Humanos
3.
Stem Cells ; 30(1): 69-74, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22102534

RESUMEN

Hearing loss, caused by irreversible loss of cochlear sensory hair cells, affects millions of patients worldwide. In this concise review, we examine the conundrum of inner ear stem cells, which obviously are present in the inner ear sensory epithelia of nonmammalian vertebrates, giving these ears the ability to functionally recover even from repetitive ototoxic insults. Despite the inability of the mammalian inner ear to regenerate lost hair cells, there is evidence for cells with regenerative capacity because stem cells can be isolated from vestibular sensory epithelia and from the neonatal cochlea. Challenges and recent progress toward identification of the intrinsic and extrinsic signaling pathways that could be used to re-establish stemness in the mammalian organ of Corti are discussed.


Asunto(s)
Oído Interno/citología , Células Ciliadas Auditivas Internas/citología , Células Madre/citología , Animales , Aves/anatomía & histología , Aves/fisiología , Diferenciación Celular/fisiología , Cóclea/citología , Cóclea/fisiología , Epitelio/anatomía & histología , Epitelio/metabolismo , Células Ciliadas Auditivas Internas/fisiología , Pérdida Auditiva/terapia , Humanos , Mamíferos/anatomía & histología , Mamíferos/fisiología , Órgano Espiral/citología , Órgano Espiral/fisiología , Regeneración/fisiología , Especificidad de la Especie , Células Madre/fisiología
4.
Stem Cells ; 28(9): 1541-9, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20665739

RESUMEN

Human embryonic stem cells (hESC) hold great promise for the treatment of patients with many neurodegenerative diseases particularly those arising from cell loss or neural dysfunction including spinal cord injury. This study evaluates the therapeutic effects of transplanted hESC-derived oligodendrocyte progenitors (OPC) and/or motoneuron progenitors (MP) on axonal remyelination and functional recovery of adult rats after complete spinal cord transection. OPC and/or MP were grafted into the site of injury in the acute phase. Based on Basso-Beattie-Bresnahan scores recovery of locomotor function was significantly enhanced in rats treated with OPC and/or MP when compared with control animals. When transplanted into the spinal cord immediately after complete transection, OPC and MP survived, migrated, and differentiated into mature oligodendrocytes and neurons showing in vivo electrophysiological activity. Taken together, these results indicate that OPC and MP derived from hESC could be a useful therapeutic strategy to repair injured spinal cord.


Asunto(s)
Células Madre Embrionarias/trasplante , Actividad Motora , Neuronas Motoras/trasplante , Regeneración Nerviosa , Oligodendroglía/trasplante , Traumatismos de la Médula Espinal/cirugía , Animales , Diferenciación Celular , Movimiento Celular , Supervivencia Celular , Células Cultivadas , Modelos Animales de Enfermedad , Células Madre Embrionarias/metabolismo , Potenciales Evocados Motores , Regulación de la Expresión Génica , Proteínas Fluorescentes Verdes/biosíntesis , Proteínas Fluorescentes Verdes/genética , Humanos , Neuronas Motoras/metabolismo , Regeneración Nerviosa/genética , Oligodendroglía/metabolismo , Ratas , Recuperación de la Función , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Traumatismos de la Médula Espinal/fisiopatología , Factores de Tiempo , Transfección
5.
Stem Cells Dev ; 19(11): 1745-56, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20521974

RESUMEN

The cerebellum has critical roles in motor and sensory learning and motor coordination. Many cerebellum-related disorders indicate cell therapy as a possible treatment of neural loss. Here we show that application of inductive signals involved in early patterning of the cerebellar region followed by application of different factors directs human embryonic stem cell differentiation into cerebellar-like cells such as granule neurons, Purkinje cells, interneuron, and glial cells. Neurons derived using our protocol showed a T-shaped polarity phenotype and express similar markers to the developed human cerebellum. Electrophysiological measurements confirmed functional electrical properties compatible with these cells. In vivo implantation of differentiated human embryonic stem cells transfected with MATH1-GFP construct into neonatal mice resulted in cell migration across the molecular and the Purkinje cell layers and settlement in the internal molecular layers. Our findings demonstrate that the universal mechanisms involved in the development of cerebellum can be efficiently recapitulated in vitro, which enables the design of new strategies for cell replacement therapy, to study early human development and pathogenesis of neurodegenerative diseases.


Asunto(s)
Diferenciación Celular/fisiología , Cerebelo/citología , Células Madre Embrionarias/citología , Células Madre Embrionarias/fisiología , Neuronas/fisiología , Potenciales de Acción , Adulto , Anciano , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Biomarcadores/metabolismo , Movimiento Celular , Células Cultivadas , Femenino , Feto/anatomía & histología , Edad Gestacional , Humanos , Masculino , Ratones , Persona de Mediana Edad , Neuronas/citología , Técnicas de Placa-Clamp , Embarazo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Trasplante de Células Madre , Adulto Joven
6.
Stem Cells ; 28(1): 93-9, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19904738

RESUMEN

Spinal cord injury (SCI) causes myelopathy, damage to white matter, and myelinated fiber tracts that carry sensation and motor signals to and from the brain. The gray matter damage causes segmental losses of interneurons and motoneurons and restricts therapeutic options. Recent advances in stem cell biology, neural injury, and repair, and the progress toward development of neuroprotective and regenerative interventions are the basis for increased optimism. This review summarizes the pathophysiological mechanisms following SCI and compares human embryonic, adult neural, and the induced pluripotent stem cell-based therapeutic strategies for SCI.


Asunto(s)
Células Madre Adultas/trasplante , Células Madre Embrionarias/trasplante , Células Madre Pluripotentes Inducidas/trasplante , Regeneración Nerviosa , Neuronas/trasplante , Medicina Regenerativa/métodos , Traumatismos de la Médula Espinal/cirugía , Trasplante de Células Madre , Adulto , Células Madre Adultas/metabolismo , Animales , Diferenciación Celular , Proliferación Celular , Células Madre Embrionarias/metabolismo , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Neuronas/metabolismo , Transducción de Señal , Traumatismos de la Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/patología , Traumatismos de la Médula Espinal/fisiopatología , Resultado del Tratamiento
7.
Psychiatry Res ; 170(2-3): 271-2, 2009 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-19896210

RESUMEN

The impact of a single nucleotide polymorphism (SNP) in the CD24 gene on the risk and progression of multiple sclerosis (MS) was investigated in the Iranian population. Our data revealed that the susceptibility and the progression of MS in individuals with the CD24V/V genotype were greater than in those with the CD24A/V and CD24A/A genotypes.


Asunto(s)
Antígeno CD24/genética , Predisposición Genética a la Enfermedad , Esclerosis Múltiple/genética , Esclerosis Múltiple/fisiopatología , Polimorfismo de Nucleótido Simple/genética , Análisis de Varianza , Distribución de Chi-Cuadrado , Progresión de la Enfermedad , Frecuencia de los Genes , Genotipo , Humanos , Irán , Grupos de Población/genética
8.
Stem Cells ; 27(3): 733-43, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19259940

RESUMEN

Spinal cord injury (SCI) is a major cause of paralysis. Currently, there are no effective therapies to reverse this disabling condition. The presence of ependymal stem/progenitor cells (epSPCs) in the adult spinal cord suggests that endogenous stem cell-associated mechanisms might be exploited to repair spinal cord lesions. epSPC cells that proliferate after SCI are recruited by the injured zone, and can be modulated by innate and adaptive immune responses. Here we demonstrate that when epSPCs are cultured from rats with a SCI (ependymal stem/progenitor cells injury [epSPCi]), these cells proliferate 10 times faster in vitro than epSPC derived from control animals and display enhanced self renewal. Genetic profile analysis revealed an important influence of inflammation on signaling pathways in epSPCi after injury, including the upregulation of Jak/Stat and mitogen activated protein kinase pathways. Although neurospheres derived from either epSPCs or epSPCi differentiated efficiently to oligodendrocites and functional spinal motoneurons, a better yield of differentiated cells was consistently obtained from epSPCi cultures. Acute transplantation of undifferentiated epSPCi or the resulting oligodendrocyte precursor cells into a rat model of severe spinal cord contusion produced a significant recovery of motor activity 1 week after injury. These transplanted cells migrated long distances from the rostral and caudal regions of the transplant to the neurofilament-labeled axons in and around the lesion zone. Our findings demonstrate that modulation of endogenous epSPCs represents a viable cell-based strategy for restoring neuronal dysfunction in patients with spinal cord damage.


Asunto(s)
Epéndimo/citología , Traumatismos de la Médula Espinal/terapia , Médula Espinal/citología , Médula Espinal/patología , Trasplante de Células Madre/métodos , Células Madre/citología , Animales , Apoptosis , Western Blotting , Diferenciación Celular/fisiología , Proliferación Celular , Supervivencia Celular , Electrofisiología , Femenino , Citometría de Flujo , Inmunohistoquímica , Oligodendroglía/citología , Análisis de Secuencia por Matrices de Oligonucleótidos , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Madre/metabolismo , Células Madre/fisiología
9.
Stem Cells ; 27(1): 78-87, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18845761

RESUMEN

Human embryonic stem cells (hESCs) are self-renewing pluripotent cells that have the capacity to differentiate into a wide variety of cell types. This potentiality represents a promising source to overcome many human diseases by providing an unlimited supply of all cell types, including cells with neural characteristics. Therefore, this review summarizes early neural development and the potential of hESCs to differentiate under in vitro conditions, examining at the same time the potential use of differentiated hESCs for therapeutic applications for neural tissue and cell regeneration.


Asunto(s)
Diferenciación Celular , Células Madre Embrionarias/citología , Neuronas/citología , Humanos , Oligodendroglía/citología , Especificidad de Órganos
10.
PLoS One ; 3(5): e2122, 2008 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-18461168

RESUMEN

BACKGROUND: Human embryonic stem cells (hESC) provide a unique model to study early events in human development. The hESC-derived cells can potentially be used to replace or restore different tissues including neuronal that have been damaged by disease or injury. METHODOLOGY AND PRINCIPAL FINDINGS: The cells of two different hESC lines were converted to neural rosettes using adherent and chemically defined conditions. The progenitor cells were exposed to retinoic acid (RA) or to human recombinant basic fibroblast growth factor (bFGF) in the late phase of the rosette formation. Exposing the progenitor cells to RA suppressed differentiation to rostral forebrain dopamine neural lineage and promoted that of spinal neural tissue including motor neurons. The functional characteristics of these differentiated neuronal precursors under both, rostral (bFGF) and caudalizing (RA) signals were confirmed by patch clamp analysis. CONCLUSIONS/SIGNIFICANCE: These findings suggest that our differentiation protocol has the capacity to generate region-specific and electrophysiologically active neurons under in vitro conditions without embryoid body formation, co-culture with stromal cells and without presence of cells of mesodermal or endodermal lineages.


Asunto(s)
Diferenciación Celular/fisiología , Desarrollo Embrionario/fisiología , Células Madre Embrionarias/citología , Neuronas/citología , Neuronas/fisiología , Técnicas de Cultivo de Célula/métodos , Línea Celular , Medios de Cultivo , Electrofisiología , Humanos , Inmunohistoquímica , Especificidad de Órganos , Técnicas de Placa-Clamp , ARN/genética , ARN/aislamiento & purificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
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