Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 8 de 8
Filter
1.
J Cell Biochem ; 121(2): 954-962, 2020 02.
Article in English | MEDLINE | ID: mdl-31609010

ABSTRACT

Diabetic retinopathy (DR) is a serious complication of diabetes contributing to blindness in patients. Inhibiting retinal neovascularization is a potent strategy for diabetic retinopathy treatment. Reportedly, the stable expression of lin-28 homolog B (LIN28B), a member of the highly conserved RNA-binding protein LIN28 family, could promote vascular endothelial growth factor (VEGF) expression; herein, we investigated the role and mechanism of LIN28B in diabetic retinopathy progression from the perspective of microRNA (miRNA) regulation. We identified miR-152 as a miRNA that may target the LIN28B 3'-untranslated region and can be significantly downregulated under high-glucose (HG) condition. The expression of miR-152 was remarkably suppressed, whereas the expression of LIN28B was significantly increased under HG condition within both human retinal endothelial cells (hRECs) and retinal microvascular endothelial cell line (hRMECs). miR-152 overexpression significantly suppressed, while LIN28B overexpression promoted the angiogenesis and the protein levels of proangiogenesis factors in both hRECs and hRMECs. More importantly, LIN28B overexpression could remarkably attenuate the effect of miR-152 overexpression. In summary, miR-152 overexpression could inhibit HG-induced angiogenesis in both hRECs and hRMECs via targeting LIN28B and suppressing VEGF signaling. Further, in vivo experiments are needed for the application of miR-152/LIN28B axis in the treatment for diabetic retinopathy.


Subject(s)
Endothelial Cells/metabolism , Glucose/metabolism , MicroRNAs/metabolism , Neovascularization, Pathologic/metabolism , RNA-Binding Proteins/metabolism , Retinal Vessels/metabolism , Signal Transduction , Vascular Endothelial Growth Factor A/metabolism , Endothelial Cells/pathology , Glucose/genetics , Humans , MicroRNAs/genetics , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/pathology , RNA-Binding Proteins/genetics , Retinal Vessels/pathology , Vascular Endothelial Growth Factor A/genetics
2.
Viruses ; 11(2)2019 02 08.
Article in English | MEDLINE | ID: mdl-30744035

ABSTRACT

The double-stranded RNA-binding protein Staufen1 (Stau1) has multiple functions during RNA virus infection. In this study, we investigated the role of Stau1 in viral translation by using a combination of enterovirus 71 (EV-A71) infection, RNA reporter transfection, and in vitro functional and biochemical assays. We demonstrated that Stau1 specifically binds to the 5'-untranslated region of EV-A71 viral RNA. The RNA-binding domain 2-3 of Stau1 is responsible for this binding ability. Subsequently, we created a Stau1 knockout cell line using the CRISPR/Cas9 approach to further characterize the functional role of Stau1's interaction with viral RNA in the EV-A71-infected cells. Both the viral RNA accumulation and viral protein expression were downregulated in the Stau1 knockout cells compared with the wild-type naïve cells. Moreover, dysregulation of viral RNA translation was observed in the Stau1 knockout cells using ribosome fractionation assay, and a reduced RNA stability of 5'-UTR of the EV-A71 was also identified using an RNA stability assay, which indicated that Stau1 has a role in facilitating viral translation during EV-A71 infection. In conclusion, we determined the functional relevance of Stau1 in the EV-A71 infection cycle and herein describe the mechanism of Stau1 participation in viral RNA translation through its interaction with viral RNA. Our results suggest that Stau1 is an important host factor involved in viral translation and influential early in the EV-A71 replication cycle.


Subject(s)
Cytoskeletal Proteins/metabolism , Enterovirus A, Human/physiology , Host Microbial Interactions , RNA, Viral/genetics , RNA-Binding Proteins/metabolism , Virus Replication , 5' Untranslated Regions , CRISPR-Cas Systems , Cell Line, Tumor , Cytoskeletal Proteins/genetics , Gene Knockout Techniques , Humans , Protein Biosynthesis , RNA-Binding Proteins/genetics
3.
J Am Chem Soc ; 139(39): 13811-13820, 2017 10 04.
Article in English | MEDLINE | ID: mdl-28885839

ABSTRACT

Supramolecular polymeric gels cross-linked by well-defined, discrete metal-organic macrocycles (MOMs) or metal-organic cages have become a prevailing topic within the field of supramolecular self-assembly. However, the realization of supramolecular polymeric hydrogels cross-linked by discrete organometallic architectures with good biocompatibility is still a great challenge. Herein, we present the successful preparation of CO2 stimuli-responsive, injectable block copolymer hydrogels cross-linked by discrete organoplatinum(II) metallacycles. Through the combination of coordination-driven self-assembly and stepwise post-assembly polymerization, star block copolymers (SBCPs) containing well-defined hexagonal metallacycles as cores were successfully prepared, which featured CO2 stimuli-responsive properties including CO2-triggered morphology transition and CO2-induced thermoresponsive behavior. Interestingly, the resultant SBCPs were capable of forming supramolecular hydrogels with MOMs as junctions near physiological temperature, which allowed the realization of a reversible gel-to-sol transformation through the removal and addition of CO2. More importantly, the resultant supramolecular hydrogels presented good cytocompatibility in vitro. Therefore, this study provides a new strategy for the construction of new "smart" supramolecular hydrogels with promising applications as biological materials.

5.
IEEE Trans Image Process ; 22(12): 5010-21, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24043388

ABSTRACT

In prediction-error expansion (PEE) based reversible data hiding, better exploiting image redundancy usually leads to a superior performance. However, the correlations among prediction-errors are not considered and utilized in current PEE based methods. Specifically, in PEE, the prediction-errors are modified individually in data embedding. In this paper, to better exploit these correlations, instead of utilizing prediction-errors individually, we propose to consider every two adjacent prediction-errors jointly to generate a sequence consisting of prediction-error pairs. Then, based on the sequence and the resulting 2D prediction-error histogram, a more efficient embedding strategy, namely, pairwise PEE, can be designed to achieve an improved performance. The superiority of our method is verified through extensive experiments.

6.
Dis Aquat Organ ; 73(1): 13-22, 2006 Nov 21.
Article in English | MEDLINE | ID: mdl-17240748

ABSTRACT

Requiring only simple heating devices, isothermal nucleic acid-based amplification (NASBA) is a potential detection platform to be developed for on-site diagnosis of aquaculture pathogens. In this report, an NASBA assay has been developed for the Taura syndrome virus (TSV), one of the most devastating RNA virus pathogens for several penaeid shrimp species. The NASBA amplicons were detected by agarose gel electrophoresis and confirmed by Northern-blotting and dot-blotting analysis, using a biotinylated TSV-specific primer. The sensitivity of the TSV NASBA coupled with dot-blotting detection was approximately 5-fold less sensitive than that of the commercially available RT-nested, PCR-based IQ2000 TSV Detection and Prevention System that was also confirmed to be more sensitive than the RT-PCR-based TSV detection protocol recommended by the OIE (Office International des Epizooties). The specificity of the TSV NASBA reaction was substantiated by the results that RNA of non-target viruses did not generate any signals. Furthermore, a simple colorimetric microtiter plate assay employing TSV-specific capture and detection primers was developed as a simple alternative approach for the detection of NASBA amplicons. Taken together, the combination of the isothermal NASBA and colorimetric solid phase-based assays should allow sensitive, straightforward, and speedy on-site detection of TSV.


Subject(s)
Aquaculture/methods , Nucleic Acid Amplification Techniques/veterinary , Penaeidae/virology , RNA Viruses/isolation & purification , Animals , Blotting, Northern/veterinary , Colorimetry/veterinary , DNA Probes/chemistry , Electrophoresis, Agar Gel/veterinary , Immunoblotting/veterinary , RNA Viruses/genetics , Reverse Transcriptase Polymerase Chain Reaction/veterinary , Sensitivity and Specificity , Taiwan , Time Factors
7.
Invest Ophthalmol Vis Sci ; 44(1): 154-9, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12506068

ABSTRACT

PURPOSE: To investigate the phosphorylation of the heavy neurofilament subunit (NF-H), which could be deeply involved in axonal transport of retinal ganglion cells (RGCs), in an experimental glaucoma model of chronic elevation of intraocular pressure (IOP) in monkeys. METHODS: One eye in adult monkeys was randomly selected for laser treatment, and IOP was maintained between 30 and 40 mm Hg throughout the experiment. The eyeballs with the optic nerve and optic chiasm were enucleated as one tissue and were subject to immunocytochemical observation, using two NF-H-specific antibodies, NF-200 and SMI31. NF-200 reacts with both phosphorylated and dephosphorylated NF-H, whereas SMI reacts only with phosphorylated NF-H. Ratios of SMI31-positive to NF-200-positive areas were calculated for quantitative evaluation of phosphorylation status. Specimens from the retina, lamina cribrosa (LC), post-LC, and optic chiasm were evaluated separately. Phosphorylation of NF-H at the retina and optic nerve head was compared between specimens from temporal retina and nasal retina, or between temporal and nasal regions of the optic disc. The status of phosphorylation was confirmed by Western blot analysis. RESULTS: An enlargement of the disc cup was observed on the temporal side, and the superior and inferior poles were preferentially involved in the neuronal damage in laser-treated eyes. Most NF-Hs in the control eyes were phosphorylated in all investigated regions, whereas those in the glaucomatous eyes were significantly dephosphorylated, and NF-Hs in the temporal region were significantly dephosphorylated compared with those in the nasal region. At the optic chiasm, NF-Hs in axons traveling from laser-treated eyes were highly dephosphorylated, and the extent of NF-H dephosphorylation corresponded to the degree of glaucoma-induced axonal damage. Western blot analysis showed the change in the phosphorylation of NF-Hs. CONCLUSIONS: NF-Hs in RGC axons are dephosphorylated by elevated IOP, which may be deeply involved in glaucoma-induced damage to axonal transport.


Subject(s)
Glaucoma/metabolism , Neurofilament Proteins/metabolism , Optic Nerve Diseases/metabolism , Animals , Axons/metabolism , Axons/pathology , Blotting, Western , Chronic Disease , Disease Models, Animal , Fluorescent Antibody Technique, Indirect , Glaucoma/complications , Intraocular Pressure , Macaca , Optic Chiasm/metabolism , Optic Chiasm/pathology , Optic Disk/metabolism , Optic Disk/pathology , Optic Nerve Diseases/etiology , Phosphorylation , Protein Isoforms/metabolism , Retinal Ganglion Cells/metabolism
8.
Ophthalmic Epidemiol ; 9(2): 97-104, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11821975

ABSTRACT

This study was undertaken to validate a WHO methodology for the rapid assessment of trachoma. Fourteen villages were chosen by random sampling in two counties in Hainan Province, China. For the rapid assessment, trichiasis patients were identified, 50 children ages 1-10 years were examined for active trachoma, and information was collected on community access to services and community risk factors. To validate the methodology, a prevalence survey was undertaken simultaneously in the same villages. For the prevalence survey, 2428 people from 1606 households in the 14 villages were chosen by random sampling. Very little active trachoma was found by either method, although the rates of trichiasis were more substantial. Ranking of the villages by the two methods for trichiasis was highly correlated (Spearman's correlation coefficient = 0.60, p = 0.02). For active trachoma, the Spearman's correlation coefficient for the ranking of villages by the two methods was 0.40 and not significant (p = 0.14), suggesting that a correlation this close may have been seen by chance alone. The observational data showed all the villages to be at risk of active trachoma (due to poor environmental hygiene conditions), suggesting that this aspect of the WHO methodology overestimates the risk for active trachoma. We conclude that, with the exception of the community assessment of risk, this rapid assessment methodology is a valid tool for the assessment of trichiasis and possibly of active trachoma in rural communities, although the level of active trachoma in this study was too low to effectively validate that aspect of the methodology.


Subject(s)
Diagnostic Techniques, Ophthalmological , Trachoma/diagnosis , Trachoma/epidemiology , Child , Child, Preschool , China/epidemiology , Developing Countries , Humans , Infant , Prevalence , Risk Factors , World Health Organization
SELECTION OF CITATIONS
SEARCH DETAIL
...