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911.
Jongjin Park Dong Gwang Lee Na Geum Lee Min-Gi Kwon Yeon Sung Son Mi-Young Son Kwang-Hee Bae Jangwook Lee Jong-Gil Park Nam-Kyung Lee Jeong-Ki Min 《BMB reports》2022,55(3):142
Human pluripotent stem cells (PSCs) have been utilized as a promising source in regenerative medicine. However, the risk of teratoma formation that comes with residual undifferentiated PSCs in differentiated cell populations is most concerning in the clinical use of PSC derivatives. Here, we report that a monoclonal antibody (mAb) targeting PSCs could distinguish undifferentiated PSCs, with potential teratoma-forming activity, from differentiated PSC progeny. A panel of hybridomas generated from mouse immunization with H9 human embryonic stem cells (hESCs) was screened for ESC-specific binding using flow cytometry. A novel mAb, K312, was selected considering its high stem cell-binding activity, and this mAb could bind to several human induced pluripotent stem cells and PSC lines. Cell-binding activity of K312 was markedly decreased as hESCs were differentiated into embryoid bodies or by retinoic acid treatment. In addition, a cell population negatively isolated from undifferentiated or differentiated H9 hESCs via K312 targeting showed a significantly reduced expression of pluripotency markers, including Oct4 and Nanog. Furthermore, K312-based depletion of pluripotent cells from differentiated PSC progeny completely prevented teratoma formation. Therefore, our findings suggest that K312 is utilizable in improving stem cell transplantation safety by specifically distinguishing residual undifferentiated PSCs. 相似文献
912.
Xincheng Yao Taeyoon Son Jiechao Ma 《Experimental biology and medicine (Maywood, N.J.)》2022,247(4):289
A portable, low cost, widefield fundus camera is essential for developing affordable teleophthalmology. However, conventional trans-pupillary illumination used in traditional fundus cameras limits the field of view (FOV) in a snapshot image, and frequently requires pharmacologically pupillary dilation for reliable examination of eye conditions. This minireview summarizes recent developments in alternative illumination approaches for widefield fundus photography. Miniaturized indirect illumination has been used to enable compact design for developing low cost, portable, widefield fundus camera. Contact mode trans-pars-planar illumination has been validated for ultra-widefield fundus imaging of infant eyes. Contact-free trans-pars-planar illumination has been explored for widefield imaging of adult eyes. Trans-palpebral illumination has been also demonstrated in a smartphone-based widefield fundus imager to foster affordable teleophthalmology. 相似文献
913.
Glycosylation sites and site-specific glycosylation in human Tamm- Horsfall glycoprotein 总被引:4,自引:1,他引:3
The N-glycosylation sites of human Tamm-Horsfall glycoprotein from one
healthy male donor have been characterized, based on an approach using
endoproteinase Glu-C (V-8 protease, Staphylococcus aureus ) digestion and a
combination of chromatographic techniques, automated Edman sequencing, and
fast atom bombardment mass spectrometry. Seven out of the eight potential
N-glycosylation sites, namely, Asn52, Asn56, Asn208, Asn251, Asn298,
Asn372, and Asn489, turned out to be glycosylated, and the potential
glycosylation site at Asn14, being close to the N-terminus, is not used.
The carbohydrate microheterogeneity on three of the glycosylation sites was
studied in more detail by high-pH anion-exchange chromatographic profiling
and 500 MHz1H-NMR spectroscopy. Glycosylation site Asn489 contains mainly
di- and tri-charged oligosaccharides which comprise, among others, the
GalNAc4 S (beta1-4)GlcNAc terminal sequence. Only glycosylation site Asn251
bears oligomannose-type carbohydrate chains ranging from Man5GlcNAc2to
Man8GlcNAc2, in addition to a small amount of complex- type structures.
Profiling of the carbohydrate moieties of Asn208 indicates a large
heterogeneity, similar to that established for native human Tamm-Horsfall
glycoprotein, namely, multiply charged complex-type carbohydrate
structures, terminated by sulfate groups, sialic acid residues, and/or the
Sda-determinant.
相似文献
914.
Large-scale growth and taxane production in cell cultures of Taxus cuspidata (Japanese yew) using a novel bioreactor 总被引:4,自引:0,他引:4
S. H. Son S. M. Choi Y. H. Lee K. B. Choi S. R. Yun J. K. Kim H. J. Park O. W. Kwon E. W. Noh J. H. Seon Y. G. Park 《Plant cell reports》2000,19(6):628-633
A novel type of bioreactor was successfully developed for the production of taxol and its precursors by culturing cells of
Taxus cuspidata (Japanese yew) on a pilot-scale. Rapidly growing cell lines were selected from callus cultures derived from immature embryos
of yew. The cells were inoculated in 20-l capacity bioreactors of different types to test the growth performance. The models
of small-scale bioreactors incorporated in this study included a balloon-type bubble bioreactor (BTBB), a bubble-column bioreactor
(BCB), a BCB with a split-plate internal loop, a BCB with a concentric draught-tube internal loop, a BCB with a fluidized
bed bioreactor, and two different models of stirred tank reactors. Among the reactors, BTBB appeared to be the most efficient
in promoting cell growth. The doubling time of cell growth in BTBB was 12 days with a 30% inoculation cell density. The optimum
time for medium replacement or feeding was 12–15 days after inoculation as determined by monitoring both the levels of sugars
and medium conductivity. When yew tree cells were grown in different sizes (100–500-l) of BTBBs, more than 70% cell viability
was recorded at the time of harvest. The growth pattern of the cells in the pilot-scale BTBB appeared to be the same as that
of cells in the 20-l bioreactors. Approximately 3 mg/l of taxol and 74 mg/l total taxanes were obtained after 27 days of culture.
Received: 6 April 1999 / Revision received: 23 August 1999 / Accepted: 31 August 1999 相似文献
915.
Boxwood is a representative ornamental shrub that is widely used in landscaping horticulture. After pruning, damaged leaves or stems of boxwoods are unavoidably vulnerable to infection by various plant pathogens. Several boxwood diseases caused by fungi, such as Volutella blight and Macrophoma leaf spot, have been reported worldwide including Republic of Korea. In this study, we isolated and identified fungal pathogens of boxwood diseases that occurred in Korea and characterized their morphological and taxonomic characteristics. Boxwood samples showing blight symptoms were collected in Seoul, Republic of Korea, and the putative fungal pathogens Pseudonectria buxi, P. foliicola, and Neofusicoccum buxi were successfully identified. Investigation of the morphological features of the field isolates, including mycelial growth and conidial morphology, and phylogenetic analysis of multiple DNA barcode loci revealed that there were some morphological and genetic variations among isolates, but all of the analyzed isolates were closely related to the corresponding reference strains. We also found that P. foliicola strains were more virulent than P. buxi, and the N. buxi strains isolated in this study were weak pathogens or saprophytes. The results of our study will contribute to the development of control strategies for boxwood diseases caused by fungi and accelerate research on the complex ecology of boxwood diseases. 相似文献
916.
Son Seunghyun; Platt Trevor; Fuentes-Yaco Cesar; Bouman Heather; Devred Emmanuel; Wu Yongsheng; Sathyendranath Shubha 《Journal of plankton research》2007,29(8):687-697
Physical and biogeochemical changes induced by the HurricaneFabian in the Northwest Atlantic in early September 2003 wereobserved using composite satellite images. After the passageof the hurricane, the mean sea surface temperature (SST) alongthe track decreased on average by about 1.3°C with maximumdecrease of 10°C. At the same time, the mean Chl a concentrationincreased by about 42%. Entrainment of cold, nutrient-rich watersby vertical mixing induced by the hurricane seems to have enhancedthe phytoplankton production. Asymmetric distribution of changesin SST and Chl a (strong intensity on the right side of thestorm track) was observed from the satellite data. The storm-inducednitrate increase estimated from the satellite SST, using a localrelationship between nitrate and temperature measurements wasabout 40% on average along the track of the storm. A numericalmodel study and climatological nutrient profile showed an increasein mixed-layer depth of 26 m and nitrate increase of about 0.2µmol L1 after the storm passage. In addition toaltering the physicochemical conditions of the water column,physical forcing by the hurricane also changed the taxonomiccomposition of phytoplankton. It is inferred that the dominanceof diatoms after the storm is a result of the increase in nutrientconcentration within the mixed layer due to the wind forcingof the storm. 相似文献
917.
Critical Impact of Hole Transporting Layers and Back Electrode on the Stability of Flexible Organic Photovoltaic Module
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Properties of hole transporting layers (HTLs) and back electrode are very critical to the stability of inverted bulk heterojunction organic photovoltaic (OPV) modules. Here, various deposition methods for back electrodes and materials of HTLs are examined by applying to inverted organic solar cells with a structure of indium tin oxide/ZnO/photoactive layer/poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/Ag. The experiment is performed on encapsulated modules with flexible barrier films under accelerated conditions. The OPV modules with screen‐printed Ag electrodes are shown to be electrically unstable with a reduction of the current density under damp heat condition at 85 °C/85% RH. Optical images for the active layer/PEDOT:PSS interface reveal that a reaction between the solvent from the Ag electrode and the underlying layers is the major cause for the degradation. In comparison with materials of the HTLs, the PEDOT:PSS layer shows low stability compared to the MoO3 layer under the accelerated conditions. Unusual chemical changes in the PEDOT:PSS film are observed through X‐ray photoelectron spectroscopy and this is further addressed by correlating the stability of the OPV devices. 相似文献
918.
Parinaz Fozouni Sungmin Son María Díaz de León Derby Gavin J. Knott Carley N. Gray Michael V. D’Ambrosio Chunyu Zhao Neil A. Switz G. Renuka Kumar Stephanie I. Stephens Daniela Boehm Chia-Lin Tsou Jeffrey Shu Abdul Bhuiya Maxim Armstrong Andrew R. Harris Pei-Yi Chen Jeannette M. Osterloh Melanie Ott 《Cell》2021,184(2):323-333.e9
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919.
Leo AB Joosten Erik Lubberts Monique MA Helsen Tore Saxne Christina JJ Coenen-de Roo Dick Heinegård Wim B van den Berg 《Arthritis research & therapy》1999,1(1):81-11
Destruction of cartilage and bone are hallmarks of human rheumatoid arthritis (RA), and controlling these erosive processes
is the most challenging objective in the treatment of RA. Systemic interleukin-4 treatment of established murine collagen-induced
arthritis suppressed disease activity and protected against cartilage and bone destruction. Reduced cartilage pathology was
confirmed by both decreased serum cartilage oligomeric matrix protein (COMP) and histological examination. In addition, radiological
analysis revealed that bone destruction was also partially prevented. Improved suppression of joint swelling was achieved
when interleukin-4 treatment was combined with low-dose prednisolone treatment. Interestingly, synergistic reduction of both
serum COMP and inflammatory parameters was noted when low-dose interleukin-4 was combined with prednisolone. Systemic treatment
with interleukin-4 appeared to be a protective therapy for cartilage and bone in arthritis, and in combination with prednisolone
at low dosages may offer an alternative therapy in RA. 相似文献
920.
Jae Bok Heo Woo Young Bang Se Won Kim Sung Min Hwang Young Sim Son Chak Han Im Biswa R. Acharya Chul Wook Kim Sam Woong Kim Byung Hyun Lee Jeong Dong Bahk 《Planta》2010,232(4):861-871
In yeast and mammals, the Yip/PRA1 family of proteins has been reported to facilitate the delivery of Rab GTPases to the membrane by dissociating the Rab–GDI complex during vesicle trafficking. Recently, we identified OsPRA1, a plant Yip/PRA1 homolog, as an OsRab7-interacting protein that localizes to the prevacuolar compartment, which suggests that it plays a role in vacuolar trafficking of plant cells. Here, we show that OsPRA1 is essential for vacuolar trafficking and that it has molecular properties that are typical of the Yip/PRA1 family of proteins. A trafficking assay using Arabidopsis protoplasts showed that the point mutant OsPRA1(Y94A) strongly inhibits the vacuolar trafficking of cargo proteins, but has no inhibitory effect on the plasma membrane trafficking of H+-ATPase-GFP, suggesting its specific involvement in vacuolar trafficking. Moreover, OsPRA1 was shown to be an integral membrane protein, suggesting that its two hydrophobic domains may mediate membrane integration, and its cytoplasmic N- and C-terminal regions were found to be important for binding to OsRab7. OsPRA1 also interacted with OsVamp3, implying its involvement in vesicle fusion. Finally, we used a yeast expression system to show that OsPRA1 opposes OsGDI2 activity and facilitates the delivery of OsRab7 to the target membrane. Taken together, our results support strongly that OsPRA1 targets OsRab7 to the tonoplast during vacuolar trafficking. 相似文献