nardosinane-type sesquiterpenoids from the formosan soft coral Paralemnalia thyrsoides     

Huang CY  Su JH  Chen BW  Wen ZH  Hsu CH  Dai CF  Sheu JH  Sung PJ 《Marine drugs》2011,9(9):1543-1553

Five new nardosinane-type sesquiterpenoids, paralemnolins Q-U (1-5), along with three known compounds (6-8), were isolated from the Formosan soft coral Paralemnalia thyrsoides. The structures of new metabolites were elucidated on the basis of extensive spectroscopic methods, and the absolute configuration of 1 was determined by the application of Mosher's method on 1. Among these metabolites, 1 and 3 are rarely found nardosinane-type sesquiterpenoids, possessing novel polycyclic structures. Compounds 1, 3, 6 and 7 were found to possess neuroprotective activity.  相似文献   

Antcin B and its ester derivative from Antrodia camphorata induce apoptosis in hepatocellular carcinoma cells involves enhancing oxidative stress coincident with activation of intrinsic and extrinsic apoptotic pathway     

Hsieh YC  Rao YK  Whang-Peng J  Huang CY  Shyue SK  Hsu SL  Tzeng YM 《Journal of agricultural and food chemistry》2011,59(20):10943-10954

The triterpenoids methylantcinate B (MAB) and antcin B (AB), isolated from the medicinal mushroom Antrodia camphorata , have been identified as strong cytotoxic agents against various type of cancer cells; however, the mechanisms of MAB- and AB-induced cytotoxicity have not been adequately explored. This study investigated the roles of caspase cascades, reactive oxygen species (ROS), DNA damage, mitochondrial disruption, and Bax and Bcl-2 proteins in MAB- and AB-induced apoptosis of hepatocellular carcinoma (HCC) HepG2 cells. Here, we showed that MAB and AB induced apoptosis in HepG2 cells, as characterized by increased DNA fragmentation, cleavage of PARP, sub-G1 population, chromatin condensation, loss of mitochondrial membrane potential, and release of cytochrome c. Increasing the levels of caspase-2, -3, -8, and -9 activities was involved in MAB- and AB-induced apoptosis, and they could be attenuated by inhibitors of specific caspases, indicating that MAB and AB triggered the caspase-dependent apoptotic pathway. Additionally, the enhanced apoptotic effect correlates with high expression of Fas, Fas ligand, as well as Bax and decreased protein levels of Bcl-(XL) and Bcl-2, suggesting that both the extrinsic and intrinsic apoptosis pathways were involved in the apoptotic processes. Incubation of HepG2 cells with antioxidant enzymes superoxide dismutase and catalase and antioxidants N-acetylcysteine and ascorbic acid attenuated the ROS generation and apoptosis induced by MAB and AB, which indicate that ROS plays a pivotal role in cell death. NADPH oxidase activation was observed in MAB- and AB-stimulated HepG2 cells; however, inhibition of such activation by diphenylamine significantly blocked MAB- and AB-induced ROS production and increased cell viability. Taken together, our results provide the first evidence that triterpenoids MAB and AB induced a NADPH oxidase-provoked oxidative stress and extrinsic and intrinsic apoptosis as a critical mechanism of cause cell death in HCC cells.  相似文献   

Expression frequency of c‐kit isoforms and its prognostic potential in canine mammary tumours     

Yi‐Chen Chen  Jiunn‐Wang Liao  Shih‐Chieh Chang  Wei‐Li Hsu 《Veterinary and comparative oncology》2020,18(3):303-314

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Comparison of direct measurement of intracranial pressures and presumptive clinical and magnetic resonance imaging indicators of intracranial hypertension in dogs with brain tumors     

Savannah Giannasi  Yukitaka Kani  Fang-Chi Hsu  John H. Rossmeisl 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(4):1514-1523

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Pharmacokinetics,tissue residues,and ex vivo pharmacodynamics of tylosin against Mycoplasma anatis in ducks     

Sara T. Elazab  Nahla S. Elshater  Yousreya H. Hashem  Seung-Chun Park  Walter H. Hsu 《Journal of veterinary pharmacology and therapeutics》2020,43(1):57-66

The pharmacokinetics of tylosin were investigated in 3 groups of ducks (n = 6). They received a single dose of tylosin (50 mg/kg) by intravenous (IV), intramuscular (IM), and oral administrations, respectively. Plasma samples were collected at various time points to 24 hr post-administration to evaluate tylosin concentration over time. Additionally, tylosin residues in tissues and its withdrawal time were assessed using 30 ducks which received tylosin orally (50 mg/kg) once daily for 5 consecutive days. After IV administration, the volume of distribution, elimination half-life, area under the plasma concentration–time curve, and the total body clearance were 7.07 ± 1.98 L/kg, 2.04 hr, 19.47 µg hr/ml, and 2.82 L hr⁻¹ kg⁻¹, respectively. After IM and oral administrations, the maximum plasma concentrations were 3.70 and 2.75 µg/ml achieved at 1 and 2 hr, and the bioavailability was 93.95% and 75.77%, respectively. The calculated withdrawal periods of tylosin were 13, 8, and 5 days for kidney, liver, and muscle, respectively. For the pharmacodynamic profile, the minimum inhibitory concentration for tylosin against M. anatis strain 1,340 was 1 µg/ml. The calculated optimal oral dose of tylosin against M. anatis in ducks based on the ex vivo pharmacokinetic/pharmacodynamic modeling was 61 mg kg⁻¹ day⁻¹.  相似文献   

Combination of Fish Oil and Selenium Enhances Anticancer Efficacy and Targets Multiple Signaling Pathways in Anti-VEGF Agent Treated-TNBC Tumor-Bearing Mice     

Chih-Hung Guo  Simon Hsia  Chieh-Han Chung  Yi-Chun Lin  Min-Yi Shih  Pei-Chung Chen  Guoo-Shyng W. Hsu  Ciou-Ting Fan  Chia-Lin Peng 《Marine drugs》2021,19(4)

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Integrated Omics Strategy Reveals Cyclic Lipopeptides Empedopeptins from Massilia sp. YMA4 and Their Biosynthetic Pathway     

Shang-Tse Ho  Ying-Ning Ho  Chih Lin  Wei-Chen Hsu  Han-Jung Lee  Chia-Chi Peng  Han-Tan Cheng  Yu-Liang Yang 《Marine drugs》2021,19(4)

Empedopeptins—eight amino acid cyclic lipopeptides—are calcium-dependent antibiotics that act against Gram-positive bacteria such as Staphylococcus aureus by inhibiting cell wall biosynthesis. However, to date, the biosynthetic mechanism of the empedopeptins has not been well identified. Through comparative genomics and metabolomics analysis, we identified empedopeptin and its new analogs from a marine bacterium, Massilia sp. YMA4. We then unveiled the empedopeptin biosynthetic gene cluster. The core nonribosomal peptide gene null-mutant strains (ΔempC, ΔempD, and ΔempE) could not produce empedopeptin, while dioxygenase gene null-mutant strains (ΔempA and ΔempB) produced several unique empedopeptin analogs. However, the antibiotic activity of ΔempA and ΔempB was significantly reduced compared with the wild-type, demonstrating that the hydroxylated amino acid residues of empedopeptin and its analogs are important to their antibiotic activity. Furthermore, we found seven bacterial strains that could produce empedopeptin-like cyclic lipopeptides using a genome mining approach. In summary, this study demonstrated that an integrated omics strategy can facilitate the discovery of potential bioactive metabolites from microbial sources without further isolation and purification.  相似文献   

Effects of divalent cations on nadh‐linked electron transfer in corn root plasma membrane     

Shu‐I Tu  Deidre Patterson  David Braver  An‐Fei Hsu 《Journal of plant nutrition》2013,36(5):923-936

The effects of calcium (Ca²⁺), cadmium (Cd²⁺), and copper (Cu²⁺) cations on NADH‐linked electron transfer in com root plasma membrane vesicles were investigated. The reduction of both cytochrome c and ferricyanide were slightly stimulated by Ca²⁺ but not significantly affected by Cd²⁺. However, Cd²⁺ induced a redox‐linked increase in light scattering suggesting an increase in the size/volume of the vesicles. The presence of micromolar levels of Cu²⁺ decreased the reduction rates of both cytochrome c and ferricyanide. However, in contrast to ferricyanide reduction, Cu inhibition to the cytochrome c reduction was more effective, and was less sensitive to ionic strength. Copper inhibition changed the Michaelis‐Menten dependence of the ferricyanide reduction but not that of cytochrome c. These results suggest that the reduction of cytochrome c. and ferricyanide must occur at different membrane sites.  相似文献   

Bioactive cembranoids from the soft coral Sinularia crassa     

Chao CH  Chou KJ  Huang CY  Wen ZH  Hsu CH  Wu YC  Dai CF  Sheu JH 《Marine drugs》2011,9(10):1955-1968

Eight new cembranoids, crassarines A-H (1-8) were isolated from the Formosan soft coral Sinularia crassa. Compounds 1-3 represent the rare cembranoids with a 1,12-oxa-bridged tetrahydrofuran ring, while 4 and 5 are the firstly discovered 1,11-oxa-bridged tetrahydropyranocembranoids. The absolute configuration of 6 was determined using the Mosher's method. Compounds 6 and 8 were found to significantly inhibit the expression of both pro-inflammatory iNOS and COX-2 proteins at 10 μM, respectively, while compounds 4-8 were found to be non-cytotoxic toward the selected human liver cancer cells.  相似文献   

Ballistic-resistant stainless steel mesh compound nonwoven fabric     

Chia-Chang Lin  Chao-Chiung Huang  You-Liang Chen  Ching-Wen Lou  Chin-Mei Lin  Chan-Hung Hsu  Jia-Horng Lin 《Fibers and Polymers》2008,9(6):761-767

The energy of impact must decay and be transmitted after a bullet is shot through a ballistic-resistant cloth with a laminate structure. A rigid net structure transmits the impact stress to reduce the breakage of the material in the direction perpendicular to the fabric after the impacting of a projectile. This work combines the rigid net structure of stainless steel mesh with two layers a needle-punched polyamide nonwoven fabric to create a sandwich-like laminate structure. A compound fabric that is composed of a stainless steel mesh and polyamide nonwoven fabrics is placed in multi-layer Kevlar fabrics, and the buffer effect is measured by performing a dropping weight impact test and a bullet-shooting test. The specifications of the stainless steel mesh and the order of placement of the compound fabrics are varied to show the effect of these parameters on the energy of fracture propagation and the buffer effect of the multi-layered Kevlar compound fabric that includes a layer of compound fabric that is made of stainless steel mesh and polyamide nonwoven fabrics. In this study, the compound fabric replaces several layers of Kevlar unidirectional fabric, to be used to reduce the cost of bulletproof vests without reducing ballistic resistance.  相似文献