7 results on '"Wu, Shih-Hsiung"'
Search Results
2. A medically relevant capsular polysaccharide in Acinetobacter baumannii is a potential vaccine candidate.
- Author
-
Yang FL, Lou TC, Kuo SC, Wu WL, Chern J, Lee YT, Chen ST, Zou W, Lin NT, and Wu SH
- Subjects
- Acinetobacter Infections microbiology, Acinetobacter baumannii chemistry, Acinetobacter baumannii isolation & purification, Animals, Bacterial Vaccines chemistry, Bacterial Vaccines isolation & purification, Cross-Sectional Studies, Disease Models, Animal, Humans, Longitudinal Studies, Mice, Polysaccharides, Bacterial chemistry, Polysaccharides, Bacterial isolation & purification, Taiwan, Acinetobacter Infections prevention & control, Acinetobacter baumannii immunology, Bacterial Vaccines immunology, Polysaccharides, Bacterial immunology
- Abstract
Concerns of Acinetobacter baumannii infection have increased due to the emergence of multi-drug resistance. In the present study, we determined the capsular polysaccharide (CPS) structure of A. baumannii SK44, a clinical isolate from Taiwan, to consist of pentasaccharide repeats. We found that CPS-induced antibody provided 55% protection against challenge in an animal model. The CPS-specific antibody reacted with the surface components of about 62% clinical isolates (342/554 strains) from cross-sectional and longitudinal studies by dot-immunoassay. Pulsed-field gel electrophoresis of positive strains showed the antibody covered different clonalites of A. baumannii clinical isolates. Meanwhile, using the CPS antibody as a probe, we found a number of outer membrane proteins bound to the antibody, including OmpA/motB, TonB-dependent receptor, and Omp38, indicating their association with CPS. These results might lead to the use of the capsular polysaccharide as a vaccine to prevent A. baumannii infection., (Copyright © 2017 Elsevier Ltd. All rights reserved.)
- Published
- 2017
- Full Text
- View/download PDF
3. New Meroterpenoids from Aspergillus terreus with Inhibition of Cyclooxygenase-2 Expression.
- Author
-
Liaw CC, Yang YL, Lin CK, Lee JC, Liao WY, Shen CN, Sheu JH, and Wu SH
- Subjects
- Crystallography, X-Ray, Lipopolysaccharides pharmacology, Macrophages drug effects, Magnetic Resonance Spectroscopy, Molecular Structure, Taiwan, Aspergillus chemistry, Cyclooxygenase 2 Inhibitors chemistry, Cyclooxygenase 2 Inhibitors metabolism, Pyrones chemistry, Sesquiterpenes chemistry, Sesterterpenes biosynthesis, Sesterterpenes chemistry
- Abstract
Two novel meroterpenoids, yaminterritrems A (1) and B (2), were isolated from Aspergillus terreus collected from hot spring zones in Yang-Ming Mountain, Taiwan, and cultured at 40 °C. The structures of 1 and 2 were elucidated by NMR, MS spectral and X-ray crystallographic analyses. The biosynthetic route for 1 and 2 involving the conversion of the sesquiterpene with phenyl-α-pyrone is proposed. Besides, 2 exhibited a dose-dependent inhibitory effect on COX-2 expression in LPS-stimulated RAW264.7 macrophages.
- Published
- 2015
- Full Text
- View/download PDF
4. Generation of reactive oxygen species by polyenylpyrroles derivatives causes DNA damage leading to G2/M arrest and apoptosis in human oral squamous cell carcinoma cells.
- Author
-
Hua KF, Liao PC, Fang Z, Yang FL, Yang YL, Chen YL, Chiu YC, Liu ML, Lam Y, and Wu SH
- Subjects
- Animals, Antineoplastic Agents pharmacology, Carcinoma, Squamous Cell metabolism, Caspase 3 metabolism, Cell Death drug effects, Cell Division drug effects, Cell Line, Tumor, Cytochromes c metabolism, Female, G2 Phase drug effects, Humans, Membrane Potential, Mitochondrial drug effects, Mice, Mice, Inbred BALB C, Mice, Nude, Mitochondria drug effects, Mitochondria metabolism, Mouth Neoplasms metabolism, Oxidative Stress drug effects, Taiwan, Apoptosis drug effects, Carcinoma, Squamous Cell drug therapy, Cell Cycle Checkpoints drug effects, DNA Damage drug effects, Mouth Neoplasms drug therapy, Pyrones pharmacology, Pyrroles pharmacology, Reactive Oxygen Species metabolism
- Abstract
Oral squamous cell carcinoma (OSCC) accounts for 5.8% of all malignancies in Taiwan and the incidence of OSCC is on the rise. OSCC is also a common malignancy worldwide and the five-year survival rate remains poor. Therefore, new and effective treatments are needed to control OSCC. In the present study we have investigated the efficacy and associated mechanisms of polyenylpyrroles and their analogs in both in vitro cell culture and in vivo nude mice xenografts. Auxarconjugatin B (compound 1a) resulted in cell cycle arrest in the G2/M phase and caspase-dependent apoptosis in OEC-M1 and HSC-3 cells by activating DNA damage and mitochondria dysfunction through the loss of mitochondrial membrane potential, release of cytochrome c, increase in B-cell lymphoma-2-associated X protein level, and decrease in B-cell lymphoma-2 level. Compound 1a-induced generation of intracellular reactive oxygen species through cytochrome P450 1A1 was identified as a major mechanism of its effect for DNA damage, mitochondria dysfunction and apoptosis, which was reversed by antioxidant N-acetylcysteine as well as cytochrome P450 1A1 inhibitor and specific siRNA. Furthermore, compound 1a-treated nude mice showed a reduction in the OEC-M1 xenograft tumor growth and an increase in the caspase-3 activation in xenograft tissue. These results provide promising insights as to how compound 1a mediates cytotoxicity and may prove to be a molecular rationale for its translation into a potential therapeutic against OSCC.
- Published
- 2013
- Full Text
- View/download PDF
5. Chemical composition and bioactivities of the marine alga Isochrysis galbana from Taiwan.
- Author
-
Yu CC, Chen HW, Chen MJ, Chang YC, Chien SC, Kuo YH, Yang FL, Wu SH, Chen J, Yu HH, and Chao LK
- Subjects
- Animals, Cell Survival drug effects, Cells, Cultured, Interleukin-1beta biosynthesis, Macrophages drug effects, Macrophages immunology, Mice, Polysaccharides pharmacology, Taiwan, Haptophyta chemistry, Polysaccharides chemistry
- Abstract
The present study investigated the chemical composition of Isochrysis galbana Parke, a marine microalga which is widely used as a feedstock in aquaculture. From gas chromatography/mass spectrometric analysis the mono-sugar compositions of I. galbana were 2.1% fucose, 2.5% rhamnose, 2.7% arabinose, 8.5% xylose, 15.7% mannose, 32.7% galactose and 35.8% glucose. The polysaccharides of I. galbana were able to induce prointerleukin-1beta (pro-IL-1beta) protein expression within murine macrophages. Furthermore, five kinds of chlorophyll and one sterol were separated from the ethanolic extracts, including pheophorbide-a, ethyl pheophorbide-a, 10S-10-hydroxypheophytin-a, 10R-10-hydroxypheophytin-a, (132-R)-pheophytin-a, and brassicasterol. In addition, the major soluble components of the ethanol/n-hexane extract were 9-octadecenoic acid (E) (38.4%), hexadecanoic acid (23.3%), tetradecanoic acid (15.7%), and octadecanoic acid (7.2%), but only a few polyunsaturated fatty acids were found, such as 9,12,15-octadecatrienoic acid (1.9%), 9,12-octadecadienoic acid (Z,Z) (3.4%), and docosahexaenoic acid (0.2%). This is the first occasion that polysaccharides from I. galbana have been demonstrated to exert immunomodulatory properties by the induction of IL-1 within macrophages.
- Published
- 2010
6. Mono-tetrahydrofuran annonaceous acetogenins from Annona squamosa as cytotoxic agents and calcium ion chelators.
- Author
-
Liaw CC, Yang YL, Chen M, Chang FR, Chen SL, Wu SH, and Wu YC
- Subjects
- Acetogenins chemistry, Antineoplastic Agents, Phytogenic chemistry, Drug Screening Assays, Antitumor, Female, Humans, Molecular Structure, Taiwan, Acetogenins isolation & purification, Acetogenins pharmacology, Annona chemistry, Antineoplastic Agents, Phytogenic isolation & purification, Antineoplastic Agents, Phytogenic pharmacology, Plants, Medicinal chemistry
- Abstract
Eight new mono-tetrahydrofuran (THF)-type annonaceous acetogenins, squafosacins B, C, F, and G (1-4), squadiolins A-C (5-7), and cis-annotemoyin-1 (8), as well as eight known annonaceous acetogenins, glabranin, annotemoyins-1 and -2, bullatencin, cis-bullatencin, and uvariamicins-I, -II, and -III, were isolated from the seeds of Annona squamosa by HPLC. The structures of all new isolates were elucidated by using spectroscopic and chemical methods. Squadiolins A (5) and B (6) showed ng/mL potency against human Hep G2 hepatoma cells and significant cytotoxic activity against human MDA-MB-231 breast cancer cells. Squafosacin B (1) also exhibited significant cytotoxic activity against human Hep G2 and 3B hepatoma and MCF-7 breast cancer cells. In addition, the chelation of mono-THF acetogenins with calcium ions was investigated using isothermal titration calorimetry.
- Published
- 2008
- Full Text
- View/download PDF
7. Rubrobacter taiwanensis sp. nov., a novel thermophilic, radiation-resistant species isolated from hot springs.
- Author
-
Chen MY, Wu SH, Lin GH, Lu CP, Lin YT, Chang WC, and Tsay SS
- Subjects
- Actinobacteria physiology, Actinobacteria radiation effects, Aerobiosis, Bacterial Typing Techniques, DNA, Bacterial chemistry, DNA, Bacterial isolation & purification, DNA, Ribosomal chemistry, DNA, Ribosomal isolation & purification, Fatty Acids analysis, Gamma Rays, Genes, rRNA genetics, Hot Temperature, Molecular Sequence Data, Nucleic Acid Hybridization, Phylogeny, Pigments, Biological biosynthesis, RNA, Bacterial genetics, RNA, Ribosomal, 16S genetics, Sequence Analysis, DNA, Taiwan, Temperature, Water Microbiology, Actinobacteria classification, Actinobacteria isolation & purification, Hot Springs microbiology
- Abstract
Two novel bacteria, with an optimum growth temperature of approximately 60 degrees C, were isolated from Lu-shan hot springs in the central region of Taiwan. These isolates were aerobic, thermophilic, halotolerant, pink-pigmented, heterotrophic and resistant to gamma-radiation. Both pleomorphic, short, rod-shaped cells and coccoid cells were observed. Strains LS-286 (= ATCC BAA-452 = BCRC 17198) and LS-293T (= ATCC BAA-406T = BCRC 17173T) represented a novel species of the genus Rubrobacter, according to a phylogenetic analysis of the 16S rRNA gene, DNA-DNA hybridization, biochemical features and fatty acid composition. The name Rubrobacter taiwanensis sp. nov. is proposed for this novel species, with LS-293T as the type strain.
- Published
- 2004
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.