1,142 research outputs found
Leber's Hereditary Optic Neuropathy: A Case Report
Leber's hereditary optic neuropathy (LHON) is a maternally inherited mitochondrial disease that primarily affects the optic nerve, causing bilateral vision loss in juveniles and young adults. A 12-year-old boy had complained of blurred vision in both eyes for more than 1 year. His best-corrected visual acuity was 0.08 in the right eye and 0.1 in the left. Ophthalmologic examination showed bilateral optic disc hyperemia and margin blurring, peripapillary telangiectasis, and a relative afferent pupil defect in his right eye. Fluorescein angiography showed no stain or leakage around the optic disc in the late phase. Visual field analysis showed central scotoma in the left eye and a near-total defect in the right. Upon examination of the patient's mitochondrial DNA, a point mutation at nucleotide position 11778 was found, and the diagnosis of LHON was confirmed. Coenzyme Q10 was used to treat the patient
Different RNA patterns of globin and non-globin 40S heterogeneous nuclear RNA-protein complexes in chicken reticulocyte nuclei
40s hetergeneous nuclear RNA-protein complex (HnRNP) was isolated from chicken reticulocyte nuclei after digestion of RNA by the endogenous nuclease. The size of the total RNA and β globin RNA was compared by agarose and high resolution acrylamide gel electrophoresis. The results show that size of the total RNA ranges between 20 to 650 bases and the most prominent sizes are between 20 and 70–80 bases. The size of the RNA increases at roughly 10 base intervals between 40 and 70 bases on an acrylamide gel. The size of the β globin RNA is smaller (25–50 bases) than the total RNA and also the RNA pattern is considerably different from that of total RNA. This suggests that, although the overall structure of 40s HnRNP might be the same, there is significant differences in the interaction of globin RNA with HnRNP protein and that of non-globin RNA with HnRNP protein in chicken reticulocyte nuclei
Ontology-based Fuzzy Markup Language Agent for Student and Robot Co-Learning
An intelligent robot agent based on domain ontology, machine learning
mechanism, and Fuzzy Markup Language (FML) for students and robot co-learning
is presented in this paper. The machine-human co-learning model is established
to help various students learn the mathematical concepts based on their
learning ability and performance. Meanwhile, the robot acts as a teacher's
assistant to co-learn with children in the class. The FML-based knowledge base
and rule base are embedded in the robot so that the teachers can get feedback
from the robot on whether students make progress or not. Next, we inferred
students' learning performance based on learning content's difficulty and
students' ability, concentration level, as well as teamwork sprit in the class.
Experimental results show that learning with the robot is helpful for
disadvantaged and below-basic children. Moreover, the accuracy of the
intelligent FML-based agent for student learning is increased after machine
learning mechanism.Comment: This paper is submitted to IEEE WCCI 2018 Conference for revie
Albumin fibrillization induces apoptosis via integrin/FAK/Akt pathway
[[abstract]]Background: Numerous proteins can be converted to amyloid-like fibrils to increase cytotoxicity and induce apoptosis, but the methods generally require a high concentration of protein, vigorous shaking, or fibril seed. As well, the detailed mechanism of the cytotoxic effects is not well characterized. In this study, we have developed a novel process to convert native proteins into the fibrillar form. We used globular bovine serum albumin (BSA) as a model protein to verify the properties of the fibrillar protein, investigated its cellular effects and studied the signaling cascade induced by the fibrillar protein. Results: We induced BSA, a non-cytotoxic globular protein, to become fibril by a novel process involving Superdex-200 column chromatography in the presence of anionic or zwittergenic detergent(s). The column pore size was more important than column matrix composite in fibril formation. The fibrillar BSA induced apoptosis in BHK-21 cell as well as breast cancer cell line T47D. Pre-treating cells with anti-integrin antibodies blocked the apoptotic effect. Fibrillar BSA, but not globular BSA, bound to integrin, dephosphorylated focal adhesion kinase (FAK), Akt and glycogen synthase kinase-3β (GSK-3β). Conclusion: We report on a novel process for converting globular proteins into fibrillar form to cause apoptosis by modulating the integrin/FAK/Akt/GSK-3β/caspase-3 signaling pathway. Our findings may be useful for understanding the pathogenesis of amyloid-like fibrils and applicable for the development of better therapeutic agents that target the underlying mechanism(s) of the etiologic agents. ? 2009 Huang et al; licensee BioMed Central Ltd
Evaluation of Antioxidant and Free Radical Scavenging Capacities of Polyphenolics from Pods of Caesalpinia pulcherrima
Thirteen polyphenolics were isolated from fresh pods of Caesalpinia pulcherrima using various methods of column chromatography. The structures of these polyphenolics were elucidated as gallic acid (1), methyl gallate (2), 6-O-galloyl-d-glucoside (3), methyl 6-O-galloyl-β-d-glucoside (4), methyl 3,6-di-O-galloyl-α-d-glucopyranoside (5), gentisic acid 5-O-α-d-(6′-O-galloyl)glucopyranoside (6), guaiacylglycerol 4-O-β-d-(6′-O-galloyl)glucopyranoside (7), 3-methoxy-4-hydroxyphenol 1-O-β-d-(6′-O-galloyl) glucopyranoside (8), (+)-gallocatechin (9), (+)-catechin (10), (+)-gallocatechin 3-O-gallate (11), myricetin 3-rhamnoside (12), and ampelopsin (13). All isolated compounds were tested for their antioxidant activities in the 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, and peroxynitrite radicals scavenging assays. Among those compounds, 11, 12, and 2 exhibited the best DPPH-, hydroxyl-, and peroxynitrite radical-scavenging activities, respectively. Compound 7 is a new compound, and possesses better scavenging activities towards DPPH but has equivalent hydroxyl radical scavenging activity when compared to BHT. The paper is the first report on free radical scavenging properties of components of the fresh pods of Caesalpinia pulcherrima. The results obtained from the current study indicate that the free radical scavenging property of fresh pods of Caesalpinia pulcherrima may be one of the mechanisms by which this herbal medicine is effective in several free radical mediated diseases
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