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931.
Jung-Ho Noh Ji-Seong Jeong Sang-Jin Park Kyung Jin Jung Byoung-Seok Lee Woo-Jin Kim Ji-Seok Han Min-Kyung Cho Dong Kyung Sung So Yoon Ahn Yun Sil Chang Hwa-Young Son Eun Ju Jeong 《Journal of cellular and molecular medicine》2021,25(22):10430-10440
Hypoxic-ischaemic encephalopathy (HIE) is a type of brain injury affecting approximately 1 million newborn babies per year worldwide, the only treatment for which is therapeutic hypothermia. Thrombin-preconditioned mesenchymal stem cells (MSCs) exert neuroprotective effects by enriching cargo contents and boosting exosome biogenesis, thus showing promise as a new therapeutic strategy for HIE. This study was conducted to evaluate the tissue distribution and potential toxicity of thrombin-preconditioned human Wharton's jelly-derived mesenchymal stem cells (th-hWJMSCs) in animal models before the initiation of clinical trials. We investigated the biodistribution, tumorigenicity and general toxicity of th-hWJMSCs. MSCs were administered the maximum feasible dose (1 × 105 cells/10 µL/head) once, or at lower doses into the cerebral ventricle. To support the clinical use of th-hWJMSCs for treating brain injury, preclinical safety studies were conducted in newborn Sprague-Dawley rats and BALB/c nude mice. In addition, growth parameters were evaluated to assess the impact of th-hWJMSCs on the growth of newborn babies. Our results suggest that th-hWJMSCs are non-toxic and non-tumorigenic in rodent models, survive for up to 7 days in the brain and hold potential for HIE therapy. 相似文献
932.
Katherine A. Alexander Allison Coté Son C. Nguyen Liguo Zhang Omid Gholamalamdari Paula Agudelo-Garcia Enrique Lin-Shiao K.M.A. Tanim Joan Lim Nicolas Biddle Margaret C. Dunagin Charly R. Good Mariel R. Mendoza Shawn C. Little Andrew Belmont Eric F. Joyce Arjun Raj Shelley L. Berger 《Molecular cell》2021,81(8):1666-1681.e6
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933.
Yoo-Kyoung Sohn Sumin Son Yoonjoo Choi Da-Eun Hwang Hyo-Deok Seo Joong-jae Lee Hak-Sung Kim 《Biotechnology and bioengineering》2020,117(6):1904-1908
Complement component 3a (C3a) plays a crucial role in the immune response and host defense, but it is also involved in pro-inflammatory responses, causing many inflammatory disorders. Blockade of C3a has been regarded as a potent therapeutic strategy for inflammatory diseases. Here, we present the development of a human C3a (hC3a)-specific protein binder, which effectively inhibits pro-inflammatory responses. The protein binder, which is composed of leucine-rich repeat modules, was selected against hC3a through phage display, and its binding affinity was matured up to 600 pM by further expanding the binding interface in a module-by-module manner. The developed protein binder was shown to have more than 10-fold higher specificity to hC3a compared with human C5a, exhibiting a remarkable suppression effect on pro-inflammatory response in monocyte, by blocking the interaction between hC3a and its receptor. The hC3a-specific protein binder is likely to have a therapeutic potential for C3a-mediated inflammatory diseases. 相似文献
934.
The activity of beta-site amyloid precursor protein (APP) cleaving enzyme 1 (BACE1) is elevated during aging and in sporadic Alzheimer’s disease (AD), but the underlying mechanisms of this change are not well understood. p25/Cyclin-dependent kinase 5 (Cdk5) has been implicated in the pathogenesis of several neurodegenerative diseases, including AD. Here, we describe a potential mechanism by which BACE activity is increased in AD brains. First, we show that BACE1 is phosphorylated by the p25/Cdk5 complex at Thr252 and that this phosphorylation increases BACE1 activity. Then, we demonstrate that the level of phospho-BACE1 is increased in the brains of AD patients and in mammalian cells and transgenic mice that overexpress p25. Furthermore, the fraction of p25 prepared from iodixanol gradient centrifugation was unexpectedly protected by protease digestion, suggesting that p25/Cdk5-mediated BACE1 phosphorylation may occur in the lumen. These results reveal a link between p25 and BACE1 in AD brains and suggest that upregulated Cdk5 activation by p25 accelerates AD pathogenesis by enhancing BACE1 activity via phosphorylation. 相似文献
935.
Sung Ho Son Sung Mee Choi Soo Jin Hyung Seung Rho Yun Myung Suk Choi Eun-Myoung Shin Yong-Pyo Hong 《Biotechnology and Bioprocess Engineering》1999,4(2):119-123
Among the various plant growth regulators (PGR), 9.0 μM 2,4-D(2,4-dichlorophenoxyacetic acid) turned out to be the best for
callogenesis and 4.5 μM 2,4-D was revealed to be more suitable for callus proliferation. Of the four basal media, the highest
number of 8.2 adventitious roots was induced in Woody plant medium (WPM) containing 14.8 μM IBA(indole 3-butyic acid). F tests
on each auxin treatment in the ANOVA revealed highly significant difference at α=0.01. The number of multiple adventitious
roots (MARs) formed in each adventitious roots highly depended on the types and levels of auxin tested. At both 24.6 μM and
34.4 μM IBA, more than 25 MARs were induced after 4 weeks of culture. When different medium were applied, immersion type showed
the highest fresh weight of MARs at the time of harvest. With 160 g fresh weight of inoculum, about 14.2 times of biomass
was obtained after 6 weeks of culture. Identical fractionation pattern of the amplified fragment length polymorphism (AFLP)
analysis was observed between the adventitious root and donor of a mountain ginseng. This observation suggested that any rearrangements
of the genomic DNA had not occurred in the adventitious roots after 1 year of cultures. The cultivated ginseng and the mountain
ginseng groups could be distinguished by 2 AFLP markers. 相似文献
936.
Shigehiro Hirano Tamayo Nakahira Masuo Nakagawa Son Ki Kim 《Journal of biotechnology》1999,70(1-3):373-377
Novel chitin–silk fibroin fibres and chitin fibres were prepared by an environmental friendly wet-spinning method. Each aqueous solution of sodium chitin (N-acetylchitosan) salt and its blends of silk fibroin in aqueous 14% sodium hydroxide was spun through a viscose-type spinneret into an aqueous 10% sulfuric acid solution saturated with ammonium sulfate (about 43%), and the corresponding white filament was obtained. The tenacity and elongation values of the chitin–silk fibroin filament decreased with an increase of fibroin content up to 33% by weight. A scanning electron microscopy analysis revealed that both the chitin filament and the chitin–silk fibroin (67:33, w/w) filament had vertical strips with faint scale structures on their surfaces. Some applications of these staple fibres were also reported. 相似文献
937.
Although ignorance and uncertainty are usually unwelcome feelings, they have unintuitive advantages for both human and non-human animals, which we review here. We begin with the perils of too much information: expertise and knowledge can come with illusions (and delusions) of knowing. We then describe how withholding information can counteract these perils: providing people with less information enables them to judge more precisely what they know and do not know, which in turn enhances long-term memory. Data are presented from a new experiment that illustrates how knowing what we do not know can result in helpful choices and enhanced learning. We conclude by showing that ignorance can be a virtue, as long as it is recognized and rectified. 相似文献
938.
939.
Mohammed Y. E. Chowdhury Rui Li Jae-Hoon Kim Min-Eun Park Tae-Hwan Kim Prabuddha Pathinayake Prasanna Weeratunga Man Ki Song Hwa-Young Son Seung-Pyo Hong Moon-Hee Sung Jong-Soo Lee Chul-Joong Kim 《PloS one》2014,9(4)
To develop a safe and effective mucosal vaccine against pathogenic influenza viruses, we constructed recombinant Lactobacillus casei strains that express conserved matrix protein 2 with (pgsA-CTA1-sM2/L. casei) or without (pgsA-sM2/L. casei) cholera toxin subunit A1 (CTA1) on the surface. The surface localization of the fusion protein was verified by cellular fractionation analyses, flow cytometry and immunofluorescence microscopy. Oral and nasal inoculations of recombinant L. casei into mice resulted in high levels of serum immunoglobulin G (IgG) and mucosal IgA. However, the conjugation of cholera toxin subunit A1 induced more potent mucosal, humoral and cell-mediated immune responses. In a challenge test with 10 MLD50 of A/EM/Korea/W149/06(H5N1), A/Puerto Rico/8/34(H1N1), A/Aquatic bird /Korea/W81/2005(H5N2), A/Aquatic bird/Korea/W44/2005(H7N3), and A/Chicken/Korea/116/2004(H9N2) viruses, the recombinant pgsA-CTA1-sM2/L. casei provided better protection against lethal challenges than pgsA-sM2/L. casei, pgsA/L. casei and PBS in mice. These results indicate that mucosal immunization with recombinant L. casei expressing CTA1-conjugated sM2 protein on its surface is an effective means of eliciting protective immune responses against diverse influenza subtypes. 相似文献
940.
The effects of combined cold, acid and ethanol on the membrane physical state and on the survival of Oenococcus oeni were investigated. Membrane fluidity was monitored on intact whole O. oeni cells subjected to single and combined cold, acid and ethanol shocks by using fluorescence anisotropy with 1,6-diphenyl-1,3,5-hexatriene (DPH) as a probe. Results showed that cold shocks (14 and 8 °C) strongly rigidified plasma membrane but did not affect cell survival. In contrast, ethanol shocks (10-14% v/v) induced instantaneous membrane fluidisation followed by rigidification and resulted in low viability. Acid shocks (pH 4.0 and pH 3.0) exerted a rigidifying effect on membrane without affecting cell viability. Whatever the shock orders, combined cold (14 °C) and ethanol (14% v/v) shocks resulted in strong membrane rigidification. Interestingly, O. oeni survived combined cold and ethanol shocks more efficiently than single ethanol shock. Membrane rigidification was induced by ethanol-and-acid (10% v/v - pH 3.5) shock and correlated with total cell death. In contrast, O. oeni recovered its viability when subjected to cold (8 °C)-then-ethanol-and-acid shock which strongly rigidified the membrane. Our results suggested a positive short-term effect of combined cold, acid and ethanol shocks on membrane fluidity and viability of O. oeni. 相似文献