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71.
Hye Ri Park Jiyoon Kim Taekeun Kim Seonmi Jo Miyoung Yeom Bongjin Moon Il Han Choo Jaeick Lee Eun Jeong Lim Ki Duk Park Sun-Joon Min Ghilsoo Nam Gyochang Keum C. Justin Lee Hyunah Choo 《Bioorganic & medicinal chemistry》2013,21(17):5480-5487
In Parkinson’s disease, the motor impairments are mainly caused by the death of dopaminergic neurons. Among the enzymes which are involved in the biosynthesis and catabolism of dopamine, monoamine oxidase B (MAO-B) has been a therapeutic target of Parkinson’s disease. However, due to the undesirable adverse effects, development of alternative MAO-B inhibitors with greater optimal therapeutic potential towards Parkinson’s disease is urgently required. In this study, we designed and synthesized the oxazolopyridine and thiazolopyridine derivatives, and biologically evaluated their inhibitory activities against MAO-B. Structure–activity relationship study revealed that the piperidino group was the best choice for the R1 amino substituent to the oxazolopyridine core structure and the activities of the oxazolopyridines with various phenyl rings were between 267.1 and 889.5 nM in IC50 values. Interestingly, by replacement of the core structure from oxazolopyrine to thiazolopyridine, the activities were significantly improved and the compound 1n with the thiazolopyridine core structure showed the most potent activity with the IC50 value of 26.5 nM. Molecular docking study showed that van der Waals interaction in the human MAO-B active site could explain the enhanced inhibitory activities of thiazolopyridine derivatives. 相似文献
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73.
Mi Kyung Woo Kyeong Ah Kim JuYeon Kim Jun Seo Oh Eun Taek Han Seong Soo A An Chae Seung Lim 《Memórias do Instituto Oswaldo Cruz》2013,108(3):359-367
Nucleotide sequence analyses of the Pvs48/45 and Pvs47 genes were conducted in 46 malaria patients from the Republic of Korea (ROK) (n = 40) and returning travellers from India (n = 3) and Indonesia (n = 3). The domain structures, which were based on cysteine residue position and secondary protein structure, were similar between Plasmodium vivax (Pvs48/45 and Pvs47) and Plasmodium falciparum (Pfs48/45 and Pfs47). In comparison to the Sal-1 reference strain (Pvs48/45, PVX_083235 and Pvs47, PVX_083240), Korean isolates revealed seven polymorphisms (E35K, H211N, K250N, D335Y, A376T, I380T and K418R) in Pvs48/45. These isolates could be divided into five haplotypes with the two major types having frequencies of 47.5% and 20%, respectivelfy. In Pvs47, 10 polymorphisms (F22L, F24L, K27E, D31N, V230I, M233I, E240D, I262T, I273M and A373V) were found and they could be divided into four haplotypes with one major type having a frequency of 75%. The Pvs48/45 isolates from India showed a unique amino acid substitution site (K26R). Compared to the Sal-1 and ROK isolates, the Pvs47 isolates from travellers returning from India and Indonesia had amino acid substitutions (S57T and I262K). The current data may contribute to the development of the malaria transmission-blocking vaccine in future clinical trials. 相似文献
74.
Sze-Looi Song Phaik-Eem Lim Siew-Moi Phang Weng-Wah Lee Khanjanapaj Lewmanomont Danilo B. Largo Nurridan Abdul Han 《Journal of applied phycology》2013,25(3):839-846
Gracilaria is a red seaweed that has been cultivated worldwide and is commercially used for food, fertilizers, animal fodder, and phycocolloids. However, the high morphological plasticity of seaweeds often leads to the misidentification in the traditional identification of Gracilaria species. Molecular markers are important especially in the correct identification of Gracilaria species with high economic value. Microsatellite markers were developed from the expressed sequence tags of seaweeds deposited at the National Center for Biotechnology Information database and used for differentiating Gracilaria changii collected at various localities and two other Gracilaria species. Out of 33 primer pairs, only one primer pair gave significant results that can distinguish between three different Gracilaria species as well as G. changii from various localities based on the variation in repeated nucleotides. The unweighted pair group method using arithmetic mean dendrogram analysis grouped Gracilaria species into five main clades: (a) G. changii from Batu Besar (Malacca), Sandakan (Sabah), Bintulu (Sarawak), Batu Tengah (Malacca), Gua Tanah (Malacca), Middle Banks (Penang), Sungai (Sg.) Merbok (Kedah), Teluk Pelandok (Negeri Sembilan), Pantai Dickson (Negeri Sembilan), Sg. Kong-Kong (Johore), and Sg. Pulai (Johore); (b) Gracilaria manilaensis from Cebu, Philippines; (c) G. changii from Morib (Selangor); (d) Gracilaria fisheri from Pattani, Thailand; and (e) G. changii from Pantai Dickson (Negeri Sembilan), Gua Tanah (Malacca), Sg. Merbok (Kedah), Sg. Kong-Kong (Johore), and Sg. Pulai (Johore). This result shows that this primer pair was able to distinguish between three different species, which are G. changii from Morib (Malaysia), G. fisheri from Pattani (Thailand), and G. manilaensis from Cebu (Philippines), and also between different genotypes of G. changii. This suggested that the simple sequence repeat primer we developed was suitable for differentiating between different Gracilaria species due to the polymorphisms caused by the variability in the number of tandem repeats. 相似文献
75.
Bee Ting Chan Einly Lim Chi Wei Ong Noor Azuan Abu Osman 《Computer methods in biomechanics and biomedical engineering》2013,16(1):90-96
Despite the advancement of cardiac imaging technologies, these have traditionally been limited to global geometrical measurements. Computational fluid dynamics (CFD) has emerged as a reliable tool that provides flow ?eld information and other variables essential for the assessment of the cardiac function. Extensive studies have shown that vortex formation and propagation during the filling phase acts as a promising indicator for the diagnosis of the cardiac health condition. Proper setting of the boundary conditions is crucial in a CFD study as they are important determinants, that affect the simulation results. In this article, the effect of different transmitral velocity profiles (parabolic and uniform profile) on the vortex formation patterns during diastole was studied in a ventricle with dilated cardiomyopathy (DCM). The resulting vortex evolution pattern using the uniform inlet velocity profile agreed with that reported in the literature, which revealed an increase in thrombus risk in a ventricle with DCM. However the application of a parabolic velocity profile at the inlet yields a deviated vortical flow pattern and overestimates the propagation velocity of the vortex ring towards the apex of the ventricle. This study highlighted that uniform inlet velocity profile should be applied in the study of the filling dynamics in a left ventricle because it produces results closer to that observed experimentally. 相似文献
76.
Elaine T. Lim Soumya Raychaudhuri Stephan J. Sanders Christine Stevens Aniko Sabo Daniel G. MacArthur Benjamin M. Neale Andrew Kirby Douglas M. Ruderfer Menachem Fromer Monkol Lek Li Liu Jason Flannick Stephan Ripke Uma Nagaswamy Donna Muzny Jeffrey G. Reid Alicia Hawes Mark J. Daly 《Neuron》2013,77(2):235-242
77.
Timothy W. Yu Maria H. Chahrour Michael E. Coulter Sarn Jiralerspong Kazuko Okamura-Ikeda Bulent Ataman Klaus Schmitz-Abe David A. Harmin Mazhar Adli Athar N. Malik Alissa M. D’Gama Elaine T. Lim Stephan J. Sanders Ganesh H. Mochida Jennifer N. Partlow Christine M. Sunu Jillian M. Felie Jacqueline Rodriguez Christopher A. Walsh 《Neuron》2013,77(2):259-273
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79.
Hiroki Hayase Nobumoto Watanabe Chung Liang Lim Toshihiko Nogawa Keisuke Komatsuya Kiyoshi Kita 《Bioscience, biotechnology, and biochemistry》2013,77(4):633-635
Quinomycin A and its derivatives were identified as potent antimalarial (Plasmodium falciparum) agents in a screen of the RIKEN NPDepo chemical library. IC50 values of quinomycin A and UK-63,598 were approximately 100 times lower than that of the antimalarial drug chloroquine. This activity was mitigated by the addition of plasmid DNA, suggesting that these compounds act against parasites by intercalating into their DNA. 相似文献
80.