Youngsang Cho

Functional recovery after human umbilical cord blood cells transplantation with brain-derived neutrophic factor into the spinal cord injured rat

SummaryThere have been many efforts to recover neuronal function from spinal cord injuries, but there are some limitations in the treatment of spinal cord injuries.The neural stem cell has been noted for its pluripotency to differentiate into various neural cell types. The human umbilical cord blood cells (HUCBs) are more pluripotent and genetically flexible than bone marrow neural stem cells. The HUCBs could be more frequently used for spinal cord injury treatment in the future.Moderate degree spinal cord injured rats were classified into 3 subgroups, group A: media was injected into the cord injury site, group B: HUCBs were transplanted into the cord injury site, and group C: HUCBs with BDNF (Brain-derived neutrophic factor) were transplanted into the cord injury site. We checked the BBB scores to evaluate the functional recovery in each group at 8 weeks after transplantation. We then, finally checked the neural cell differentiation with double immunofluorescence staining, and we also analyzed the axonal regeneration with retrograde labelling of brain stem neurons by using fluorogold. The HUCBs transplanted group improved, more than the control group at every week after transplantation, and also, the BDNF enabled an improvement of the BBB locomotion scores since the 1 week after its application (P<0.05). 8 weeks after transplantation, the HUCBs with BDNF transplanted group had more greatly improved BBB scores, than the other groups (P<0.001). The transplanted HUCBs were differentiated into various neural cells, which were confirmed by double immunoflorescence staining of BrdU and GFAP & MAP-2 staining. The HUCBs and BDNF each have individual positive effects on axonal regeneration. The HUCBs can differentiate into neural cells and induce motor function improvement in the cord injured rat models. Especially, the BDNF has effectiveness for neurological function improvement due to axonal regeneration in the early cord injury stage. Thus the HUCBs and BDNF have recovery effects of a moderate degree for cord injured rats.

Intermediate filament nestin expressions in human cord blood monocytes (HCMNCs).

Summary¶Objects. Nestin is an intermediate protein and a well-known specific neural stem cell antigen. Some bone marrow stem cells can generate not only blood cells but also neurons and glial cells under specific culture conditions. Furthermore, in vitro cultured bone marrow stem cells also express nestin antigen. However, it is unclear whether cord blood cells also differentiate into neural cells or not. In this study, we investigated the expression of nestin on human cord blood monocytes (HCMNCs) and we discuss the relevance of this finding upon future therapeutic applications of HCMNCs in neurological diseases. Methods. HCMNCs were prepared from normal placenta after full-term normal delivery. Immunocytochemical staining and reverse transcriptase polymerase chain reaction (RT-PCR) for nestin and CD133 antigen were performed to confirm nestin and CD133 antigen expression in the HCMNCs. Results. Some nestin expressing HCMNCs were found. Immunocytochemical staining showed that some of the blood stem cell marker CD133 expressing cells co-expressed nestin. RT-PCR demonstrated nestin and CD133 mRNA in HCMNCs, but not in adult blood monocytes. Approximately, 60 ± 8% of CD133 expressing cells expressed nestin. Conclusion. In the present study, we found that more than 60% of CD133 expressing HCMNCs also express nestin antigen in their cytoplasm, which supports the idea that cord blood stem cells can adopt a neuronal fate.

A study on three dimensional assessment of the aging condition of polymeric medium voltage cables applying very low frequency (VLF) tan δ diagnostic

Recently, diagnostic on Medium Voltage Cables using tan δ measurement that measures dissipation factor with 0.1Hz VLF (Very Low Frequency) high voltage source has emerged as an efficient way to assess water tree aging of MV (Medium Voltage) cables. This study verified the validity diagnostic evaluation criteria defined by IEEE400.2-2013 and its pervious drafts of DTD (Delta tan δ) and STDEV (Standard Deviation) - indicating voltage-stability and time-stability of tan δ respectively - by applying tan δ measurement to KEPCO (Korea Electric Power Corporation)s power distribution system and suggested a new assessment factor being defined as Skirt, and its new formula in order to identify the precursor of insulation breakdown with patterns of tan δ. By visualizing complex correlations between various assessment factors and proposing a 3-dimensional assessment standard that can normalize the deterioration condition of a cable into a uniform value, this study has established a foundation to calculate the remaining life time of a cable through VLF tan δ diagnostic.

Economic evaluation of healthcare technology improving the quality of social life: the case of assistive technology for the disabled and elderly

ABSTRACT Public investments in healthcare technology for the disabled and elderly to improve the quality of social life have been vigorous, but the economic evaluation of the assistive technology is still lacking. Under this circumstance, the purpose of this study is to analyse the socio-economic value of developing assistive technologies with the potential to improve the quality of social life, especially for disabled and elderly individuals. Based on a survey of 400 respondents, the spike model, a special form of the contingent valuation method (CVM) is applied to assess the value of assistive technologies. In Korea, a household’s willingness-to-pay (WTP) for the development of assistive technologies is US

Estimation of the inconvenience cost of a rolling blackout in the residential sector: The case of South Korea

4.26 per year, on average, in the form of a government-levied tax; although many people express zero WTP for the development of these technologies, people with higher household savings, higher levels of education and higher levels of charity donations have a higher WTP for the development of assistive technology. We conclude that although assistive technologies have considerable economic value many people express zero WTP for the development of these technologies. Therefore, political and social educational efforts are necessary to reach social consensus on the government investment in such technologies.