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Brain limited self-renewal capability is the main element behind the seriousness of neurodegenerative diseases and neural injuries. Any possible attempts to use cell replacement-therapy approaches rely on; first, the ability of such cells to generate neural cells and tissues with developmental and functional similarities to human brain cells and second, development of safe and effective protocols for cells transplantations. Many recent studies showed that human umbilical cord blood stem cells have the potential to generate cells with neuronal characteristics. It has also been shown that these stem cells have a positive impact on animal models of neural injuries and diseases. Umbilical cord blood stem cells are a potential candidate for clinical therapies for neural injuries and neural degenerative diseases for which current mode of therapy is inadequate. In addition, they might provide an in-vitro model of parenchymal neural cells for toxicology and drugs testing research.
Tissue engineering gives new tools for stem cell-based regenerative medicine and in vitro toxicology. Among different sources of stem cells human cord and cord blood are safe, clinically and ethically approved and easily obtainable sources of pluripotent stem cells able to differentiate into many tissues originated from 3 germ layers. Recently we showed that functional artifi cial neural tissue can be generated from pluripotent stem cells derived from freshly isolated human cord and cord blood stem cells in fully-defi ned culture conditions. We showed that cell starving and precise sequential introduction of single growth factors and morphogenes resulted in differentiation of pluripotent stem cells towards mature neurons in scaffold-based three-dimensional environment. The pluripotent stem cells decreased expression of the key pluripotency transcription factors: Oct4A, Sox2, Nanog, c-Myc, and acquired phenotypes of neuroblasts (Nestin+/GFAP+) followed by generation of mature neuronal networks (NeuN+, PSD95+, TUJ1+, S100beta). Finally we showed that cell–cell interactions within the 3D environment of artifi cial neural tissue were crucial for functional, electrical and calcium, activity of neural networks in vitro. We conclude that tissue-engineering approach is important for generation of functional neural tissue in vitro from cord and cord blood stem cells and therefore might be useful for future therapies of central nervous system.
Taking tissue engineering applications into clinical trials requires the development of efficient and safe protocols incorporated with effective 3-dimentional cell culturing and differentiation systems in order to develop transplantable tissues that may offer a life-line for patients in the future. Cord blood, which is perhaps the most abundant world stem cell source, has shown previously practical and ethical advantages over other stem cells sources in many research and clinical applications including regenerative medicine. We previously developed a three-step protocol for isolation, expansion and sequential neuronal differentiation of cord blood pluripotent stem cells (characterized with our unique triple immunocytochemisty scheme for Oct-4, Sox-2 and Nanog) in defined serum-free culturing conditions. In this study we incorporated this protocol with 3-dimentional culturing systems which produced artificial neuronal tissues expressing Nestin, NF-200, TUJ1, PSD-95 and NeuN. We showed that cord blood pluripotent stem cells are a potential and promising candidate for future neural tissue engineering and regenerative medicine.
Taking tissue engineering applications into clinical trials requires the development of effi cient, effective and safe protocols incorporated with effective 3-dimentional cell culturing and differentiation systems in order to develop transplantable tissues that may offer a life-line for many patients in the future. Umbilical cord blood, which is perhaps the most abundant world stem cell source, has shown previously practical and ethical advantages over other stem cells sources in many research and clinical applications including regenerative medicine. We developed a three step protocol for isolation, expansion and sequential neuronal differentiation and maturation of cord blood pluripotent stem cells (characterized with our unique triple immunocytochemisty scheme for Oct-4, Sox-2 and Nanog expression) in serum-free defi ned culturing conditions. We incorporated this protocol with 3-dimentional culturing system which produced properly organized neuronal tissues expressing Nestin and NF-200. We showed that umbilical cord blood pluripotent stem cells are a potential and promising candidate for future neural tissue engineering and regenerative medicine applications.
Umbilical cord blood contains a population of non-hematopoietic multipotent stem cells that are capable of neuronal differentiation in-vitro. These cells have shown great potential as a therapeutic tool for central nervous system diseases and disorders. However whether these cells are able to produce neurons with similar developmental and functional characteristics to indigenous neurons within the brain remains poorly investigated. In this study, we used purified umbilical cord blood non-hematopoietic stem cells to produced GABAergic neurons with similar developmental and functional characteristics to cortical GABAergic neurons. We analyzed the expression of transcription factors MASH1, DLX1 and DLX2 throughout the 24 days of a sequential neuronal induction protocol and found that their expression patterns resembled those reported in the developing human cortex. The derived neurons also expressed components of GABAergic neurotransmission including GABA regulatory enzymes, GABA receptor subunits and GABA transporters. Thus we have demonstrated that umbilical cord blood stem cells are capable of producing cortical-like GABAergic neurons in vitro. This highlights the potential of umbilical cord blood stem cells as a therapeutic tool for neural injuries and disorders.
Information on the spatial variability in plant disease is essential for location-based disease management. In the current study, the spatial distribution of tomato early blight disease was ascertained in District Gilgit, GilgitBaltistan, Pakistan. The comprehensive field survey was carried in two growing seasons (2014–2015), whereas in each growing season, 62 tomato fields were surveyed. Based on the distribution of disease, the respective thematic maps (incidence and severity) were prepared using Arc Map 10.1 with spatial analyst function of Arc GIS software by means of the inverse distance weight (IDW) interpolation method. Results indicate that early blight of tomato is spatially distributed in both growing seasons. However, in the first growing season, the disease incidence ranged from 10.22% to 44.16% and during later season 14.03–49.16%, whereas 5.37–16.40% and 6.52–26.94% severity was recorded. Furthermore, this information indicates that higher disease infestation occurred in 2015 in relation to 2014. This information linked to metrological data (temperature, precipitation and relative humidity), seemingly favored the early blight development during the growing period. Seven botanical extracts were tested against pathogen Alternaria solani at different concentrations (4, 6 and 8%). Results revealed that all tested plant extracts showed antifungal activities. However, at 8% concentration of plant extract, Datura starmonium, Berberis orthobotry, Podophyllum emodi and Uretica dioica exhibited >60%, while Peganum harmala, Artemisia maritima and Capparis spinosa <60% antifungal properties. The information generated due to this study could help the tomato growers regarding disease management and selection of resistant cultivars, improving profitability and food security in the Gilgit region.
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