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131.
Effect of bread containing resistant starch on postprandial blood glucose levels in humans 总被引:7,自引:0,他引:7
Yamada Y Hosoya S Nishimura S Tanaka T Kajimoto Y Nishimura A Kajimoto O 《Bioscience, biotechnology, and biochemistry》2005,69(3):559-566
We examined the inhibitory effect of a single ingestion of bread containing resistant starch (bread containing about 6 g of resistant starch derived from tapioca per 2 slices) (test food) on the postprandial increase in blood glucose in male and female adults with a fasting blood glucose level between 100 and 140 mg/dl. Bread not containing resistant starch (placebo) was used as the control.The study was conducted in 20 subjects (9 men and 11 women with a mean age of 50.5+/-7.5 years) using the crossover method, with a single ingestion of either bread containing resistant starch or the placebo. Blood glucose and insulin were measured before ingestion, and at 0.5, 1, 1.5, and 2 h after ingestion. The blood glucose level before ingestion was stratified into a borderline group (blood glucose level >/= 111 mg/dl) and a normal group (blood glucose level = 110 mg/dl), with the upper limit of the normal range defined as 110 mg/dl. Postprandial increases in both blood glucose and blood insulin were significantly inhibited in subjects in the borderline group who took the test food in comparison with the placebo group (blood glucose: p<0.05 and p<0.01 at 1 and 1.5 h after ingestion respectively; insulin: p<0.05, p<0.01 and p<0.05 at 1, 1.5, and 2 h after ingestion respectively).These results indicate that bread containing resistant starch is useful for prevention of lifestyle-related diseases such as diabetes mellitus, and as a supplementary means of dietetic therapy. 相似文献
132.
Malay Choudhury Takahiro Oku Shoji Yamada Masaharu Komatsu Keita Kudoh Takao Itakura Seiichi Ando 《Central European Journal of Biology》2011,6(4):545-557
Apolipoproteins such as apolipoprotein (apo) A-I, apoA-IV, and apoE are lipid binding proteins synthesized mainly in the liver
and the intestine and play an important role in the transfer of exogenous or endogenous lipids through the circulatory system.
To investigate the mechanism of lipid transport in fish, we have isolated some novel genes of the apoA-I family, apoIA-I (apoA-I isoform) 1–11, from Japanese eel by PCR amplification. Some of the isolated genes of apoIA-I corresponded to 28kDa-1 cDNAs which had already been deposited into the database and encoded an apolipoprotein with molecular
weight of 28 kDa in the LDL, whereas others seemed to be novel genes. The structural organization of all apoIA-Is consisted of four exons separated by three introns. ApoIA-I10 had a total length of 3232 bp, whereas other genes except for apoIA-I9 ranged from 1280 to 1441 bp. The sequences of apoIA-Is at the exon-intron junctions were mostly consistent with the consensus sequence (GT/AG) at exon-intron boundaries, whereas
the sequences of 3′ splice acceptor in intron 1 of apoIA-I1-7 were (AC) but not (AG). The deduced amino acid sequences of all apoIA-Is contained a putative signal peptide and a propeptide
of 17 and 5 amino acid residues, respectively. The mature proteins of apoIA-I1-3, 7, and 8 consisted of 237 amino acids, whereas
those of apoIA-I4-6 consisted of 239 amino acids. The mature apoIA-I10 sequence showed 65% identity to amino acid sequence
of apoIA-I11 which was associated with an apolipoprotein with molecular weight of 23 kDa in the VLDL. All these mature apoIA-I
sequences satisfied the common structural features depicted for the exchangeable apolipoproteins such as apoA-I, apoA-IV,
and apoE but apoIA-I11 lacked internal repeats 7, 8, and 9 when compared with other members of apoA-I family. Phylogenetic
analysis showed that these novel apoIA-Is isolated from Japanese eel were much closer to apoA-I than apoA-IV and apoE, suggesting
new members of the apoA-I family. 相似文献
133.
Akashi Ohtaki Kensuke Murata Yuichi Sato Keiichi Noguchi Hideyuki Miyatake Naoshi Dohmae Kazuhiro Yamada Masafumi Yohda Masfumi Odaka 《Biochimica et Biophysica Acta - Proteins and Proteomics》2010,1804(1):184-192
In this study, we have structurally characterized the amidase of a nitrile-degrading bacterium, Rhodococcus sp. N-771 (RhAmidase). RhAmidase belongs to amidase signature (AS) family, a group of amidase families, and is responsible for the degradation of amides produced from nitriles by nitrile hydratase. Recombinant RhAmidase exists as a dimer of about 107 kDa. RhAmidase can hydrolyze acetamide, propionamide, acrylamide and benzamide with kcat/Km values of 1.14 ± 0.23 mM− 1s− 1, 4.54 ± 0.09 mM− 1s− 1, 0.087 ± 0.02 mM− 1s− 1 and 153.5 ± 7.1 mM− 1s− 1, respectively. The crystal structures of RhAmidase and its inactive mutant complex with benzamide (S195A/benzamide) were determined at resolutions of 2.17 Å and 2.32 Å, respectively. RhAmidase has three domains: an N-terminal α-helical domain, a small domain and a large domain. The N-terminal α-helical domain is not found in other AS family enzymes. This domain is involved in the formation of the dimer structure and, together with the small domain, forms a narrow substrate-binding tunnel. The large domain showed high structural similarities to those of other AS family enzymes. The Ser-cis Ser-Lys catalytic triad is located in the large domain. But the substrate-binding pocket of RhAmidase is relatively narrow, due to the presence of the helix α13 in the small domain. The hydrophobic residues from the small domain are involved in recognizing the substrate. The small domain likely participates in substrate recognition and is related to the difference of substrate specificities among the AS family amidases. 相似文献
134.
Ginkgo biloba extract modifies hypoglycemic action of tolbutamide via hepatic cytochrome P450 mediated mechanism in aged rats 总被引:2,自引:0,他引:2
We examined hepatic cytochrome P450 (CYP)-mediated interactions between Ginkgo biloba extract (GBE) and tolbutamide, an oral anti-diabetic agent, in aged and young rats. Tolbutamide was orally given to rats with or without GBE treatment, and time-dependent changes in blood glucose were monitored. The basal activity of six CYP subtypes in liver was lower in the aged rats than in the young rats, while the inductions of these enzymes by 5 day pretreatment of 0.1% GBE diet were more in the aged rats. Further, the pretreatment of GBE significantly attenuated the hypoglycemic action of tolbutamide in the aged rats, corresponding well to the enhanced activity of (S)-warfarin 7-hydroxylase, which is responsible for CYP2C9 subtype, a major isoform metabolizing tolbutamide. In contrast, the simultaneous administration of GBE with tolbutamide potentiated the hypoglycemic action of this drug. The in vitro experiments revealed that GBE competitively inhibited the metabolism of tolbutamide by (S)-warfarin 7-hydroxylase in the rat liver microsomes. In the young rats, the 5 day pretreatment with GBE significantly attenuated the hypoglycemic action of tolbutamide, but a simultaneous treatment had little influence on the tolbutamide effect. In conclusion, the present study has shown that the simultaneous and continuous intake of GBE significantly affects the hypoglycemic action of tolbutamide, possibly via a hepatic CYP enzyme-mediated mechanism, particularly in the aged rats. Therefore, it is anticipated that the intake of GBE as a dietary supplement with therapeutic drugs should be cautious, particularly in elderly people. 相似文献
135.
Background
In bio-systems, genes, proteins and compounds are related to each other, thus forming complex networks. Although each organism has its individual network, some organisms contain common sub-networks based on function. Given a certain sub-network, the distribution of organisms common to it represents the diversity of its function. 相似文献136.
Immunohistochemical study of the developing endocrine pancreas of the opossum (Didelphis virginiana)
Cells immunoreactive for insulin, glucagon, somatostatin, bovine pancreatic polypeptide and 5-hydroxytryptamine are found in the pancreas of the newborn opossum and of all later stages examined. All immunoreactive cell types are present in primary and secondary islets and within elements of the exocrine pancreas. Cells immunoreactive for glucagon, bovine pancreatic polypeptide, somatostatin and 5-hydroxytryptamine generally are confined to the periphery of secondary (intralobular) islets, whereas insulin-immunoreactive cells occupy the central region. Endocrine cells within primary (interlobular) islets are randomly scattered. A small number of pancreatic-polypeptide-immunoreactive cells are reactive for the amine 5-hydroxytryptamine also, but the reverse is not observed. The endocrine pancreas continues to differentiate and develop throughout postnatal life and into adulthood. Little difference was observed between the head and tail regions of the opossum pancreas for the measurements made. 相似文献
137.
Takahashi N Yamada W Masuda K Araki H Tsukamoto Y Galinha A Sautès C Kato K Shimada I 《Glycoconjugate journal》1998,15(9):905-914
N-glycans of a recombinant mouse soluble Fc receptor II (sFcRII) expressed in baby hamster kidney cells were released from glycopeptides by digestion with glycoamidase A (from sweet almond), and the reducing ends of the oligosaccharides were reductively aminated with 2-aminopyridine. The derivatized N-glycans were separated and structurally identified by a three-dimensional high-performance liquid chromatography (HPLC) mapping technique on three kinds of HPLC columns [Takahashi, et al. (1995) Anal. Biochem. 226: 139–46]. Eighteen different major N-glycan structures were identified, of which six were neutral (45%), five mono-sialyl (49%), one di-sialyl (4.6%), five tri-sialyl (1.1%), and one tetra-sialyl (0.3%). All N-glycan structures determined were complex type with fucosylation at the N-acetylglucosamine residue of the reducing end, and N-acetylneuraminic acid, when present, was -(2,3)-linked. The existence of a unique structure containing both N-acetylgalactosamine and -(2,3)-N-acetylneuraminic acid residues at the reducing ends, as below, was confirmed by MALDI-TOF mass spectrometry. 相似文献
138.
Genome-wide association study identified genetic variations and candidate genes for plant architecture component traits in Chinese upland cotton 总被引:1,自引:0,他引:1
Junji Su Libei Li Chi Zhang Caixiang Wang Lijiao Gu Hantao Wang Hengling Wei Qibao Liu Long Huang Shuxun Yu 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2018,131(6):1299-1314
Key message
Thirty significant associations between 22 SNPs and five plant architecture component traits in Chinese upland cotton were identified via GWAS. Four peak SNP loci located on chromosome D03 were simultaneously associated with more plant architecture component traits. A candidate gene, Gh_D03G0922, might be responsible for plant height in upland cotton.Abstract
A compact plant architecture is increasingly required for mechanized harvesting processes in China. Therefore, cotton plant architecture is an important trait, and its components, such as plant height, fruit branch length and fruit branch angle, affect the suitability of a cultivar for mechanized harvesting. To determine the genetic basis of cotton plant architecture, a genome-wide association study (GWAS) was performed using a panel composed of 355 accessions and 93,250 single nucleotide polymorphisms (SNPs) identified using the specific-locus amplified fragment sequencing method. Thirty significant associations between 22 SNPs and five plant architecture component traits were identified via GWAS. Most importantly, four peak SNP loci located on chromosome D03 were simultaneously associated with more plant architecture component traits, and these SNPs were harbored in one linkage disequilibrium block. Furthermore, 21 candidate genes for plant architecture were predicted in a 0.95-Mb region including the four peak SNPs. One of these genes (Gh_D03G0922) was near the significant SNP D03_31584163 (8.40 kb), and its Arabidopsis homologs contain MADS-box domains that might be involved in plant growth and development. qRT-PCR showed that the expression of Gh_D03G0922 was upregulated in the apical buds and young leaves of the short and compact cotton varieties, and virus-induced gene silencing (VIGS) proved that the silenced plants exhibited increased PH. These results indicate that Gh_D03G0922 is likely the candidate gene for PH in cotton. The genetic variations and candidate genes identified in this study lay a foundation for cultivating moderately short and compact varieties in future Chinese cotton-breeding programs.139.
beta-Br-ethylamine is both a substrate and an irreversible inhibitor of amine oxidase from Aspergillus niger. The enzyme catalyzes the nonoxidative elimination of HBr from beta-Br-ethylamine to form acetaldehyde. beta-Br-ethylamine meets several criteria for an irreversible substrate analog or suicide inhibitor. 1) It inactivates the oxidized enzyme, but not the reduced enzyme. 2) The Michaelis constant for beta-Br-ethylamine in the elimination reaction showed a similar magnitude to that of the related constant found when the haloamine acted as an inhibitor. 3) The enzyme was protected from the inactivation by the co-existence of the substrate. 4) Inactivation with beta-Br-[14C]ethylamine resulted in the incorporation of radioactivity corresponding to 1 mol of the label/mol of the monomeric unit of the enzyme and a decrease of 1 mol of the -SH group. 5) Inactivation was accompanied by the formation of a new absorption peak at 320 nm which was bleached by addition of NaBH4. 相似文献
140.
A new solid-phase synthesis of oligoribonucleotides by the phosphoro-p-anisidate method using tetrahydrofuranyl protection of 2''-hydroxyl groups. 下载免费PDF全文
Six nonaribonucleotides containing the 5'-splice site, one complementary nonamer and an octadecamer containing the 3'-splice site have been synthesized on a polymer support using the phosphoro-p-anisidate method. A 5'-linked 2'-O-tetrahydrofuranyl-N-protected nucleoside 3'-(o-chlorophenyl)phosphoro-p-anisidate was used as the starting nucleotide, and the chain elongated in the 3'-direction by removing the p-anisidate protecting group with isoamyl nitrite under neutral conditions. The octadecamer has been synthesized using dinucleotide blocks and a 3'-terminal trinucleotide. 相似文献