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971.
Occurring at adenine (A) with the consensus motif GAC, N6-methyladenosine (m6A) is one of the most abundant modifications in RNA, which plays very important roles in many biological processes. The nonuniform distribution of m6A sites across the genome implies that, for better understanding the regulatory mechanism of m6A, it is indispensable to characterize its sites in a genome-wide scope. Although a series of experimental technologies have been developed in this regard, they are both time-consuming and expensive. With the avalanche of RNA sequences generated in the postgenomic age, it is highly desired to develop computational methods to timely identify their m6A sites. In view of this, a predictor called “iRNA-Methyl” is proposed by formulating RNA sequences with the “pseudo dinucleotide composition” into which three RNA physiochemical properties were incorporated. Rigorous cross-validation tests have indicated that iRNA-Methyl holds very high potential to become a useful tool for genome analysis. For the convenience of most experimental scientists, a web-server for iRNA-Methyl has been established at http://lin.uestc.edu.cn/server/iRNA-Methyl by which users can easily get their desired results without needing to go through the mathematical details. 相似文献
972.
973.
Twenty four strains representing eight species of gram positive yellow-pigmented rods (Oerskovia turbata, Oerskovia xanthineolytica, CDC Coryneform groups A-3, A-4, A-5, Listeria denitrificans, Corynebacterium aquaticum and Brevibacterium acetylicum) were divided into two major groups based on the relative amounts of 12 methyltetradecanoate (15:0a) obtained by capillary gas liquid chromatography. O. turbata, O. xanthineolytica, CDC groups A-3 and A-4, L. denitrificans and C. aquaticum were placed in the first group due to the presence of a higher percentage (29–47%) of 15:0a, than CDC group A-5 and B. acetylicum. The latter contained 2–6% of this fatty acid, and were placed in the second group.All species in the two groups except C. aquaticum and CDC group A-4, were further separated from each other based on the qualitative and quantitative differences in their fatty acid compositions. In addition, the eight strains of CDC group A-5 revealed four different patterns and were further divided into four subgroups. This study supports the importance of the composition of cellular fatty acids in differentiating some closely related organisms. 相似文献
974.
Intensive research over the last 15 years has led to the identification of several autosomal recessive and dominant
genes that cause familial Parkinson’s disease (PD). Importantly, the functional characterization of these genes has
shed considerable insights into the molecular mechanisms underlying the etiology and pathogenesis of PD. Collectively;
these studies implicate aberrant protein and mitochondrial homeostasis as key contributors to the development of PD, with
oxidative stress likely acting as an important nexus between the two pathogenic events. Interestingly, recent genome-wide
association studies (GWAS) have revealed variations in at least two of the identified familial PD genes (i.e. α-synuclein
and LRRK2) as significant risk factors for the development of sporadic PD. At the same time, the studies also uncovered
variability in novel alleles that is associated with increased risk for the disease. Additionally, in-silico meta-analyses of
GWAS data have allowed major steps into the investigation of the roles of gene-gene and gene-environment interactions
in sporadic PD. The emergent picture from the progress made thus far is that the etiology of sporadic PD is multi-factorial
and presumably involves a complex interplay between a multitude of gene networks and the environment. Nonetheless,
the biochemical pathways underlying familial and sporadic forms of PD are likely to be shared. 相似文献
975.
A therapeutic trial of bezafibrate on patients with hyperlipidemia with or without diabetes mellitus
L T Ho H L Chiang H Tsai T Y Chou C F Kwok 《Proceedings of the National Science Council, Republic of China. Part B, Life sciences》1984,8(3):240-245
Bezalip (bezafibrate), at an oral dosage of 200 mg three times a day, has been used on 12 patients with idiopathic hyperlipidemia, and on 12 patients with hyperlipidemia superimposed with diabetes mellitus. Each patient received bezafibrate for 3 months and placebo for 3 months. Blood glycosylated hemoglobin (HbA1) and fasting plasma glucose (FPG) were used as indices of diabetic control. Serum triglyceride (TG), total cholesterol (TC), high density lipoprotein-cholesterol (HDL-C), and TC/HDL-C ratio were measured and calculated in order to compare the antilipemic effects of bezafibrate with that of placebo. Non-parametric Wilcoxon test was used for statistical analysis. In both the idiopathic group and diabetic group, bezafibrate significantly lowered the serum levels of TG and TC/HDL-C, as well as elevated the level of HDL-C. The serum TC levels were not significantly altered in either of the groups. These effects could not be ascribed to an improved diabetic control, since the percent changes of HbA1 were not different between the bezafibrate periods and the placebo periods. There were no significant facial flushing, nor other side effects during the treatment with bezafibrate. It is concluded that bezafibrate has antilipemic effects, and may be helpful in reducing the atherogenic risks. 相似文献
976.
In the Lewis rat, fragment 43–88 of the highly encephalitogenic guinea-pig basic protein has been previously shown to retain the full activity of the parent protein. In the present studies this fragment was subjected to controlled chymotryptic digestion so that cleavage occurred only at tyrosine 67, generating two peptides, residues 43-67 and residues 68-88. When compared on an equimolar basis peptide 68-88 had the same encephalitogenic activity as the intact fragment and induced the same degree of immunologically specific cell response as measured by the in vitro lymphocyte stimulation test. Peptide 68-88 was further fragmented by selective tryptic cleavage at arginine 78 after blocking lysine 73 with citraconic anhydride. The two peptides, residues 68-78 and residues 79-88, were not encephalitogenic, indicating that residues adjacent to the point of cleavage contribute to the active site. 相似文献
977.
Shin-Shou Chou Eiji Taniguchi Morifusa Eto 《Bioscience, biotechnology, and biochemistry》2013,77(9):2169-2177
On irradiation with UV light the fungicide isoprothiolane (diisopropyl 1,3-dithiolan-2-ylidenemalonate) decomposed rapidly on the silica gel surface. The degradation pathways involved dithiolane ring cleavage, ester hydrolysis, decarboxylation, heterocycles formation such as dithietane and trithiolane, and sulfur liberation. The photoproducts confirmed were oxalic acid, dithiolanylidenemalonic acid, dithiolanylideneacetic acid, 2,4-bis[bis(isopropoxycar-bonyl)methylene]-1, 3-dithietane, 3, 5-bis[bis(isopropoxy-carbonyl)methylene]-1,2,4-trithiolane and sulfur. The methyl and ethyl homologs of isoprothiolane similarly gave the corresponding photoproducts. The surface area where isoprothiolane was placed appeared to be related closely with the photolysis rate. Isoprothiolane decomposed much more rapidly on sand than on a glass plate. This surface effect was greatly depressed under nitrogen atmosphere. Similar phenomena were observed with some other pesticides, with particularly those containing sulfur atoms in the molecule. 相似文献
978.
Predicting cleavability of peptide sequences by HIV protease via correlation-angle approach 总被引:2,自引:0,他引:2
James J. Chou 《Journal of Protein Chemistry》1993,12(3):291-302
In designing HIV protease inhibitors as potential drugs for AIDS therapy, knowledge about what peptide sequences in polyproteins are cleavable by HIV proteases is very useful. In this article, based on the formulation that any octapeptide can be uniquely expressed as a 160-dimensional vector and the principle that the similarity of any two such vectors is associated with their correlation angle, a new method is proposed to predict the cleavability of a peptide sequence by HIV-1 and HIV-2 proteases. The average predicted accuracy the new method for the 105 peptide sequences whose cleavability by HIV-1 protease is known is 96/105=9.14%, which is about 8% higher than that by the existing method for the same set of data. A considerably high rate of correct prediction was also obtained when the new method was used to predict the HIV-2 protease-cleaved sites in some proteins. 相似文献
979.
980.
Wei-Te Wu Su-Shan Tsai Tung-Sheng Shih Ming-Hsiu Lin Tzu-Chieh Chou Hua Ting Trong-Neng Wu Saou-Hsing Liou 《PloS one》2015,10(6)