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81.
L‐asparaginase isolated from Streptomyces ansochromogenes promotes Th1 profile and activates CD8+ T cells in human PBMC: an in vitro investigation 下载免费PDF全文
82.
Martins da Silva A Rios AF Ramos ES Lôbo RB Oliveira HN de Freitas MA 《Genetics and molecular research : GMR》2011,10(3):2140-2147
We analyzed two single nucleotide polymorphisms (SNPs) of the IGF2 and CYP21 genes in Nellore cattle participating in the Brazilian Animal Breeding Program. The SNPs were found in exon 6 of the IGF2 (insulin-like growth factor 2) gene (RFLP/MboII) as well as in the promoter region of the CYP21 (steroid 21-hydroxylase) gene (RFLP/HpaII) of these animals. The TC heterozygotes were significantly more frequent than CC and TT homozygotes in the RFLP/MboII polymorphism. The T allele was significantly more frequent than the C allele in RFLP/HpaII polymorphism. This population was found to be in Hardy-Weinberg equilibrium for these SNPs. Association of these polymorphisms with expected progeny differences of reproductive and productive traits was investigated, but proved to be significant only for DP550 (expected progeny differenced for weight at 365 days - IGF2 - RFLP/MboII) and DP450 (expected progeny differenced for weight at 450 days - CYP21 - RFLP/HpaII). This is the first study on the occurrence of these two polymorphisms in this Zebu breed of cattle. A total of 147 Nellore animals participating in the Breeding Program of the Nellore Breed (PMGRN) under the management of the National Association of Breeders and Researchers (ANCP) in the city of Ribeir?o Preto were analyzed. 相似文献
83.
Encarnação JM Rosa L Rodrigues R Pedro L da Silva FA Gonçalves J Ferreira GN 《Journal of biotechnology》2007,132(2):142-148
In this work three piezoelectric sensors modified with anti-HIV-1 Vif (virion infectivity factor) single fragment antibodies (4BL scFV), single domains (VH) and camelized single domains (VHD) were constructed and used to detect HIV1 Vif in liquid samples. Dithio-bis-succinimidyl-undecanoate (DSU) and 11-hydroxy-1-undecanethiol (HUT) mixed self assembled monolayers (SAM) were generated at the sensors surface onto which the antibodies were immobilized. All sensors detected specifically the target HIV1-Vif antigen in solution and no unspecific binding was monitored. Impedance analysis was performed to quantify electroacoustic and viscoelastic interferences during antibody immobilization and antigen recognition. The elimination of such interferences enabled the quantitative use of the piezoelectric immunosensors to estimate the antibody surface density as well as antigen binding and equilibrium constants. In spite of the possible limitation regarding mass transport and other related molecular phenomena, which were not considered in the binding model used, this work demonstrates the usefulness of piezoelectric biosensors in biorecognition analysis and evidences the advantages on using simultaneous impedance analysis to bring analytical significance to measured data, and thus to improve piezoelectric sensors sensitivity and applicability. 相似文献
84.
Khusnutdinova EK Viktorova TV Akhmetova VL Mustafina OE Fatkhlislamova RI Balanovskaia EV Petrova NV Makarov SV Kravchuk OI Paĭ GV Ginter EK 《Genetika》2003,39(11):1550-1563
Population-genetic study of indigenous populations representing three ethnic Chuvash group: highland (Cheboksarsk and Morgaush district), lowland (Kanash district) and mid-lowland (Marposad district). Eight polymorphic DNA loci of the nuclear genome (VNTR/PAH, STR/PAH, VNTR/ApoB, VNTR/DAT1, APF, VNTR/eNOS, IVS6aGATT, and KM.19/PstI) were examined in the population of each district. For each of the four population, we estimated the allele and genotype frequency distributions at each polymorphic system, heterozygosities HS and between-population differences FST. In the combined Chuvash sample, HS = 0.464 and FST = 0.006. Loci VNTR(DAT) and VNTR(ApoB) showed highest between-population differentiation (0.009 < or = FST < or = 0.012), and loci IVS6aGATT, APF, VNTR/eNOS, and D7S23 (KM.19), lowest differentiation (0.001 < or = FST < or = 0.003). Analysis of genetic distances revealed somewhat higher genetic similarity between the Cheboksarsk and Morgaush populations belonging to the highland Chuvash group, whereas the highland Chuvash population from the Marposad district, which belong to the mid-lowland group, was more distant from the former populations. 相似文献
85.
The fluorescence of the natural photosynthetic pigments beta-carotene (beta-K) and chlorophyll a (Chl) and their mixtures with bovine serum albumin (BSA) in different molar ratios has been studied. An increase in the fluorescence intensity in a pigment mixture-BSA complex was found. The highest possible (four- to sixfold) increase in the fluorescence intensity compared with fluorescence intensity of one-pigment BSA complexes BSA (beta-K) and BSA (Chl) was achieved at the ratio 11-27% beta-K/89-73% Chl in the BSA complex. A considerable overlap of fluorescence spectra of BSA (Chl) complex (lambda(max) at 690 nm) and BSA (beta-K) complex (lambda(max) at 684 nm) was observed. 相似文献
86.
Pedro LG Santos PA da Silva JA Figueiredo AC Barroso JG Deans SG Looman A Scheffer JJ 《Phytochemistry》2001,57(2):245-250
The essential oils isolated from leaves of ten and from unripe berries of eight populations of Laurus azorica (Seub.) Franco, collected on five islands of the Azorean archipelago, were analysed by GC and GC-MS. All oil samples were dominated by their monoterpene fraction (60-94%), alpha-pinene (15-37%) and 1,8-cineole (12-31%) being the main components of the leaf oils, while trans-beta-ocimene (27-45%) and alpha-pinene (12-22%) were the main components of the oils from the berries. The sesquiterpene fractions of the oils ranged from 3 to 17% and the main components were beta-caryophyllene (traces-8%) and beta-elemene (traces-3%) both in the leaf and berry oils. Some phenylpropanoid components were also present, in total amounting to 17%, trans-cinnamyl acetate (215% of the leaf oils) being the main component of this fraction. Cluster analysis of the enantiomeric composition of alpha- and beta-pinene in the oils from the leaves clearly showed two groups, one constituted by the two populations growing on the island S. Jorge, and the other constituted by the remaining populations. 相似文献
87.
Ptáková Michaela Pokorný Petr Šída Petr Novák Jan Horáček Ivan Juřičková Lucie Meduna Petr Bezděk Aleš Myšková Eva Walls Matthew Poschlod Peter 《Vegetation History and Archaeobotany》2021,30(2):269-286
Vegetation History and Archaeobotany - In a continuous, perfectly stratified sedimentary sequence which was discovered under a large sandstone overhang in northern Bohemia, Czech Republic, we... 相似文献
88.
Liu Z Bos JI Armstrong M Whisson SC da Cunha L Torto-Alalibo T Win J Avrova AO Wright F Birch PR Kamoun S 《Molecular biology and evolution》2005,22(3):659-672
Phytophthora infestans, the organism responsible for the Irish famine, causes late blight, a re-emerging disease of potato and tomato. Little is known about the molecular evolution of P. infestans genes. To identify candidate effector genes (virulence or avirulence genes) that may have co-evolved with the host, we mined expressed sequence tag (EST) data from infection stages of P. infestans for secreted and potentially polymorphic genes. This led to the identification of scr74, a gene that encodes a predicted 74-amino acid secreted cysteine-rich protein with similarity to the Phytophthora cactorum phytotoxin PcF. The expression of scr74 was upregulated approximately 60-fold 2 to 4 days after inoculation of tomato and was also significantly induced during early stages of colonization of potato. The scr74 gene was found to belong to a highly polymorphic gene family within P. infestans with 21 different sequences identified. Using the approximate and maximum likelihood (ML) methods, we found that diversifying selection likely caused the extensive polymorphism observed within the scr74 gene family. Pairwise comparisons of 17 scr74 sequences revealed elevated ratios of nonsynonymous to synonymous nucleotide-substitution rates, particularly in the mature region of the proteins. Using ML, all 21 polymorphic amino acid sites were identified to be under diversifying selection. Of these 21 amino acids, 19 are located in the mature protein region, suggesting that selection may have acted on the functional portions of the proteins. Further investigation of gene copy number and organization revealed that the scr74 gene family comprises at least three copies located in a region of no more than 300 kb of the P. infestans genome. We found evidence that recombination contributed to sequence divergence within at least one gene locus. These results led us to propose an evolutionary model that involves gene duplication and recombination, followed by functional divergence of scr74 genes. This study provides support for using diversifying selection as a criterion for identifying candidate effector genes from sequence databases. 相似文献
89.
High dietary salt decreases antioxidant defenses in the liver of fructose-fed insulin-resistant rats
Waleska Claudia Dornas Wanderson Geraldo de Lima Rinaldo Cardoso dos Santos Joyce Ferreira da Costa Guerra Melina Oliveira de Souza Maísa Silva Lorena Souza e Silva Mirla Fiuza Diniz Marcelo Eustáquio Silva 《The Journal of nutritional biochemistry》2013,24(12):2016-2022
In this study we investigated the hypothesis that a high-salt diet to hyperinsulinemic rats might impair antioxidant defense owing to its involvement in the activation of sodium reabsorption to lead to higher oxidative stress. Rats were fed a standard (CON), a high-salt (HS), or a high-fructose (HF) diet for 10 weeks after which, 50% of the animals belonging to the HF group were switched to a regimen of high-fructose and high-salt diet (HFS) for 10 more weeks, while the other groups were fed with their respective diets. Animals were then euthanized and their blood and liver were examined. Fasting plasma glucose was found to be significantly higher (approximately 50%) in fructose-fed rats than in the control and HS rats, whereas fat liver also differed in these animals, producing steatosis. Feeding fructose-fed rats with the high-salt diet triggered hyperinsulinemia and lowered insulin sensitivity, which led to increased levels of serum sodium compared to the HS group. This resulted in membrane perturbation, which in the presence of steatosis potentially enhanced hepatic lipid peroxidation, thereby decreasing the level of antioxidant defenses, as shown by GSH/GSSG ratio (HFS rats, 7.098±2.1 versus CON rats, 13.2±6.1) and superoxide dismutase (HFS rats, 2.1±0.05 versus CON rats, 2.3±0.1%), and catalase (HFS rats, 526.6±88.6 versus CON rats, 745.8±228.7 U/mg ptn) activities. Our results indicate that consumption of a salt-rich diet by insulin-resistant rats may lead to regulation of sodium reabsorption, worsening hepatic lipid peroxidation associated with impaired antioxidant defenses. 相似文献
90.
Satoshi N. Suzuki Masae I. Ishihara Masahiro Nakamura Shin Abe Tsutom Hiura Kosuke Homma Motoki Higa Daisuke Hoshino Kazuhiko Hoshizaki Hideyuki Ida Ken Ishida Motohiro Kawanishi Kazutaka Kobayashi Koichiro Kuraji Shigeo Kuramoto Takashi Masaki Kaoru Niiyama Mahoko Noguchi Haruto Nomiya Satoshi Saito Takeshi Sakai Michinori Sakimoto Hitoshi Sakio Tamotsu Sato Hirofumi Shibano Mitsue Shibata Maki Suzuki Atsushi Takashima Hiroshi Tanaka Masahiro Takagi Naoaki Tashiro Naoko Tokuchi Toshiya Yoshida Yumiko Yoshida 《Ecological Research》2012,27(6):989-990
This data paper reports litter fall data collected in a network of 21 forest sites in Japan. This is the largest litter fall data set freely available in Japan to date. The network is a part of the Monitoring Sites 1000 Project launched by the Ministry of the Environment, Japan. It covers subarctic to subtropical climate zones and the four major forest types in Japan. Twenty-three permanent plots in which usually 25 litter traps were installed were established in old-growth or secondary natural forests. Litter falls were collected monthly from 2004, and sorted into leaves, branches, reproductive structures and miscellaneous. The data provide seasonal patterns and inter-annual dynamics of litter falls, and their geographical patterns, and offer good opportunities for meta-analyses and comparative studies among forests. 相似文献