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41.
Pahangensin A and B,two new antibacterial diterpenes from the rhizomes of Alpinia pahangensis Ridley
Yasodha Sivasothy Halijah Ibrahim Audra Shaleena Paliany Siti Aisyah Alias Khalijah Awang 《Bioorganic & medicinal chemistry letters》2013,23(23):6280-6285
The rhizomes of Alpinia pahangensis Ridley yielded a new bis-labdanic diterpene for which the name pahangensin A (1) was proposed along with a new labdane diterpene, pahangensin B (2). Their structures were elucidated by spectroscopic methods including, 1D and 2D NMR techniques and LCMS-IT-TOF analysis. Pahangensin A (1) was found to be an antibacterial agent against Staphylococcus aureus, Bacillus cereus and Bacillus subtilis with MIC values less than 100 μg/mL, respectively. Pahangensin B (2) exhibited antibacterial activity (MIC <100 μg/mL) against B. cereus. 相似文献
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43.
Yoshihiro Kato Motoji Kawasaki Tomohiro Nigo Shunya Nakamura Akira Fusano Yasuhiro Teranishi Mari N. Ito Takaaki Sumiyoshi 《Bioorganic & medicinal chemistry》2013,21(18):5851-5854
A series of 2,3-disubstituted pyridines were synthesized and evaluated for their PDE4 inhibitory activity. We successfully modified undesirable cyano group of initial lead compound 2 to 4-pyridyl group with improvement of in vitro efficacy and optimized the position of nitrogen atoms in pyridine moiety and alkylene linker. The most potent compound showed significant efficacy in animal models of asthma and inflammation. 相似文献
44.
Takashi Matsumoto Daisuke Yoshida Shigenobu Mizusaki Hideo Tomita Koichi Koshimizu 《Bioscience, biotechnology, and biochemistry》2013,77(4):861-864
The mutagenic activities of quinoline, isoquinoline, phenanthridine, benzo(f)quinoline, benzo(h)quinoline and their α-amino derivatives were compared in relation to the effect of structural changes using the Salmonella typhimurium test system. All mutagenic compounds tested require the liver microsomal fraction for their mutagenic activity. Phenanthridine, two benzoquinolines and quinoline were mutagenic. α-Amination of two benzoquinolines and quinoline resulted to increase their mutagenic activity intensively. Addition of a benzene ring to the benzene moiety of 2-aminoquinoline, so that two carbon atoms are shared, affected distinctly the increase in the mutagenic activity. The co-existence of benzoquinoline series with 2-aminobenzo(f)quinoline showed the clear synergistic action. 相似文献
45.
《Bioscience, biotechnology, and biochemistry》2013,77(12):2912-2920
The textures of cooked rice prepared from aged rice grains and their improvement by reducing agents were investigated. For aged rice that was stored for 5 months without air by the operation of a vacuum packing machine, the stickiness/hardness ratio of cooked rice was as low as that of aged rice stored in air. The results of electrophoresis showed that oxidation of proteins in the former was advanced to the same degree as in the latter. The stickiness/hardness ratios of the aged rice were increased by the addition of sodium sulfite, cysteine, and dithiothreitol to the cooking water. Sodium sulfite, cysteine, and dithiothreitol cleave disulfide bonds to sulfhydryl groups. Therefore, cleaving disulfide bonds to sulfhydryl groups improved the texture. The addition of them to the cooking water also increased the extractable solids at the time of heating. Hence cleaving disulfide bonds to sulfhydryl groups must increase extractable solids. Consequently, the gelatinized paste layer thickened and the thick paste layer softened the cooked rice. 相似文献
46.
《Bioscience, biotechnology, and biochemistry》2013,77(7):1520-1526
Synthetic D- and L-amino acid type cationic 9-mer peptides (all sequences were synthesized as D- or L-amino acids) derived from the active sites of insect defensins were tested for their ability to modify the growth of blood-stream form African trypanosomes in vitro. One of them, the D-type peptide A (RLYLRIGRR-NH2), irreversibly suppressed proliferation of the Trypanosoma brucei brucei GUTat3.1 parasite. The presence of negatively charged phosphatidylserine on the surface of the parasites was demonstrated, suggesting electrostatic interaction between the peptide and the phospholipids. Furthermore, this peptide was found to alter trypanosome membrane-potentials significantly, an effect apparently due to the removal of the parasite’s plasma membrane. The potential toxic effects of D-peptide A on mammalian cells was assessed using human brain microvascular endothelial cells. Only minor effects were found when the endothelial cells were exposed for 16 h to peptide concentrations of less than 200 μM. These findings suggest that insect defensin-based peptides represent a potentially new class of membrane-disrupting trypanocidal drugs. 相似文献
47.
Elza van Deel Yanto Ridwan J. Nicole van Vliet Sasha Belenkov Jeroen Essers 《Journal of visualized experiments : JoVE》2016,(108)
The use of Micro-Computed Tomography (MicroCT) for in vivo studies of small animals as models of human disease has risen tremendously due to the fact that MicroCT provides quantitative high-resolution three-dimensional (3D) anatomical data non-destructively and longitudinally. Most importantly, with the development of a novel preclinical iodinated contrast agent called eXIA160, functional and metabolic assessment of the heart became possible. However, prior to the advent of commercial MicroCT scanners equipped with X-ray flat-panel detector technology and easy-to-use cardio-respiratory gating, preclinical studies of cardiovascular disease (CVD) in small animals required a MicroCT technologist with advanced skills, and thus were impractical for widespread implementation. The goal of this work is to provide a practical guide to the use of the high-speed Quantum FX MicroCT system for comprehensive determination of myocardial global and regional function along with assessment of myocardial perfusion, metabolism and viability in healthy mice and in a cardiac ischemia mouse model induced by permanent occlusion of the left anterior descending coronary artery (LAD). 相似文献
48.
A specific plasminogen activator inhibitor‐1 antagonist derived from inactivated urokinase 下载免费PDF全文
Zebin Hong Zhonghui Lin Min Liu Guangpu Xue Cai Yuan Lin Lin Barbara Furie Robert Flaumenhaft Peter Andreasen Bruce Furie Mingdong Huang 《Journal of cellular and molecular medicine》2016,20(10):1851-1860
Fibrinolysis is a process responsible for the dissolution of formed thrombi to re‐establish blood flow after thrombus formation. Plasminogen activator inhibitor‐1 (PAI‐1) inhibits urokinase‐type and tissue‐type plasminogen activator (uPA and tPA) and is the major negative regulator of fibrinolysis. Inhibition of PAI‐1 activity prevents thrombosis and accelerates fibrinolysis. However, a specific antagonist of PAI‐1 is currently unavailable for therapeutic use. We screened a panel of uPA variants with mutations at and near the active site to maximize their binding to PAI‐1 and identified a potent PAI‐1 antagonist, PAItrap. PAItrap is the serine protease domain of urokinase containing active‐site mutation (S195A) and four additional mutations (G37bR–R217L–C122A–N145Q). PAItrap inhibits human recombinant PAI‐1 with high potency (Kd = 0.15 nM) and high specificity. In vitro using human plasma, PAItrap showed significant thrombolytic activity by inhibiting endogenous PAI‐1. In addition, PAItrap inhibits both human and murine PAI‐1, allowing the evaluation in murine models. In vivo, using a laser‐induced thrombosis mouse model in which thrombus formation and fibrinolysis are monitored by intravital microscopy, PAItrap reduced fibrin generation and inhibited platelet accumulation following vascular injury. Therefore, this work demonstrates the feasibility to generate PAI‐1 inhibitors using inactivated urokinase. 相似文献
49.
Masaki Kikugawa Hiroyasu Tsutsuki Tomoaki Ida Hidemitsu Nakajima Hideshi Ihara 《Bioscience, biotechnology, and biochemistry》2016,80(3):547-553
Ferulic acid (FA) has been reported to exhibit protective effects against amyloid-β (Aβ)-induced neurodegeneration in vitro and in vivo. Recently, we developed two water-soluble FA derivatives: 1-feruloyl glycerol and 1-feruloyl diglycerol. In this study, we examined the neuroprotective effects of these water-soluble FA derivatives on Aβ-induced neurodegeneration both in vitro and in vivo. FA and water-soluble FA derivatives inhibited Aβ aggregation and destabilized pre-aggregated Aβ to a similar extent. Furthermore, water-soluble FA derivatives, as well as FA, inhibited Aβ-induced neuronal cell death in cultured neuronal cells. In in vivo experiments, oral administration of water-soluble FA derivatives to mice improved Aβ-induced dysmnesia assessed by contextual fear conditioning test and protected hippocampal neurons against Aβ-induced neurotoxicity. This study provides useful evidence suggesting that water-soluble FA derivatives are expected to be effective neuroprotective agents. 相似文献
50.
Kosuke Nakayama Takeshi Ohmori Satoshi Ishikawa Natsumi Iwata Yasuo Seto 《Bioscience, biotechnology, and biochemistry》2016,80(5):1024-1026
The plasmid encoding His-tagged organophosphorus hydrolase (OPH) cloned from Sphingobium fuliginis was modified to be transferred back to this bacterium. The replication function of S. amiense plasmid was inserted at downstream of OPH gene, and S. fuliginis was transformed with this plasmid. The transformant produced larger amount of active OPH with His-tag than E. coli. 相似文献