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271.
Luciano S. Pinto Celso S. Nagano Taianá M. Oliveira Tales R. Moura Alexandre H. Sampaio Henri Debray Vicente P. Pinto Odir A. Dellagostin Benildo S. Cavada 《Journal of biosciences》2008,33(3):355-363
A new galactose-specific lectin was purified from seeds of a Caesalpinoideae plant, Bauhinia variegata, by affinity chromatography on lactose-agarose. Protein extracts haemagglutinated rabbit and human erythrocytes (native and
treated with proteolytic enzymes), showing preference for rabbit blood treated with papain and trypsin. Among various carbohydrates
tested, the lectin was best inhibited by D-galactose and its derivatives, especially lactose. SDS-PAGE showed that the lectin,
named BVL, has a pattern similar to other lectins isolated from the same genus, Bauhinia purpurea agglutinin (BPA). The molecular mass of BVL subunit is 32 871 Da, determined by MALDI-TOF spectrometry. DNA extracted from
B. variegata young leaves and primers designed according to the B. purpurea lectin were used to generate specific fragments which were cloned and sequenced, revealing two distinct isoforms. The bvl gene sequence comprised an open reading frame of 876 base pairs which encodes a protein of 291 amino acids. The protein carried
a putative signal peptide. The mature protein was predicted to have 263 amino acid residues and 28 963 Da in size. 相似文献
272.
Jeanny S. Maciel Luciano S. Chaves Bartolomeu W.S. Souza Drlio I.A. Teixeira Ana L.P. Freitas Judith P.A. Feitosa Regina C.M. de Paula 《Carbohydrate polymers》2008,71(4):559-565
Water soluble polysaccharide from Gracilaria birdiae cultivated along the northeast coast of Brazil was characterized by infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopy. The composition of the polysaccharide in wt% was determined as: β-d-galp (50.3%), 3,6-anhydro--l-galp (40.5%) and --l-galp-6 sulfate (9.2%). The ratio of l/d units (β-d-galp units and 3,6-anhydro--l-galp + -l-galp-6 sulfate) is that of an ideal agarose. The sulfate content calculated by S% accounts for 6.4%. 1D and 2D NMR techniques were employed in order to assign the spin system of polysaccharide without partial degradation. The structure is composed of → 4-3,6-anhydro--l-galp (1 → 3)β-d-galp 1 → segments, with the possibility of a -l-galp unit substituted at the 6-position by sulfate ester. 相似文献
273.
Vitali L Laranjeira MC Gonçalves NS Fávere VT 《International journal of biological macromolecules》2008,42(2):152-157
In the present study, a new chelating adsorbent was prepared from chitosan microspheres cross-linked with glutaraldehyde by spray drying using 8-hydroxyquinoline -5 sulphonic acid as chelant agent (CTS-SX-CL). Microspheres of the new adsorbent were characterized by Raman spectroscopy, scanning electron microscopy (SEM) and energy-dispersive X-ray microanalysis (EDX). The effect of pH, contact time and concentration of metallic ions in solution were evaluated on the adsorption behavior of Cd(II) and Zn(II) by CTS-SX-CL. Adsorption was maximum for both Cd(II) and Zn(II) at pH 8.0. Adsorption kinetic curves were obtained and could be fit by the pseudo second-order adsorption model. An analysis of equilibrium adsorption data using the Langmuir isotherm model indicated that the maximum adsorption capacity of CTS-SX-CL was higher than that of CTS-CL for both ions investigated. The adsorption capacity increased 74% for Cd(II). 相似文献
274.
Karina Keller Marques da Costa Flaiban Kledir Anderson H. Spohr Luciano de Souza Malanski Walfrido Kühl Svoboda Marcos M. Shiozawa Carmen Lúcia S. Hilst Lucas Moraes Aguiar Gabriela Ludwig Fernando C. Passos Italmar Teodorico Navarro Mara Regina Stipp Balarin Júlio Augusto Naylor Lisbôa 《International journal of primatology》2008,29(5):1375-1382
We evaluated blood samples obtained from 80 free-ranging healthy capuchins (Cebus cay and C. nigritus) to establish hematological reference values and to assess the influence of sex and age on them. We caught the monkeys in
the Paraná River region of Southern Brazil via manual or automatic traps. We anesthetized them intramuscularly with 3.6 mg/kg
tiletamine/zolazepam hydrochlorides. After physical examinations, we divided the sample according to sex and age: 26 females
(13 adults and 13 juveniles) and 54 males (27 adults and 27 juveniles). We collected blood and determined hematological values
via traditional published methods. We analyzed data via 2-way ANOVA to test the effect of sex, age, and interactions between
the 2 factors. The packed-cell volume was higher in adult males and the numbers of white blood cells and lymphocytes were
higher in juveniles. There is no other significant difference. 相似文献
275.
276.
Schaeffer SW Bhutkar A McAllister BF Matsuda M Matzkin LM O'Grady PM Rohde C Valente VL Aguadé M Anderson WW Edwards K Garcia AC Goodman J Hartigan J Kataoka E Lapoint RT Lozovsky ER Machado CA Noor MA Papaceit M Reed LK Richards S Rieger TT Russo SM Sato H Segarra C Smith DR Smith TF Strelets V Tobari YN Tomimura Y Wasserman M Watts T Wilson R Yoshida K Markow TA Gelbart WM Kaufman TC 《Genetics》2008,179(3):1601-1655
The sequencing of the 12 genomes of members of the genus Drosophila was taken as an opportunity to reevaluate the genetic and physical maps for 11 of the species, in part to aid in the mapping of assembled scaffolds. Here, we present an overview of the importance of cytogenetic maps to Drosophila biology and to the concepts of chromosomal evolution. Physical and genetic markers were used to anchor the genome assembly scaffolds to the polytene chromosomal maps for each species. In addition, a computational approach was used to anchor smaller scaffolds on the basis of the analysis of syntenic blocks. We present the chromosomal map data from each of the 11 sequenced non-Drosophila melanogaster species as a series of sections. Each section reviews the history of the polytene chromosome maps for each species, presents the new polytene chromosome maps, and anchors the genomic scaffolds to the cytological maps using genetic and physical markers. The mapping data agree with Muller's idea that the majority of Drosophila genes are syntenic. Despite the conservation of genes within homologous chromosome arms across species, the karyotypes of these species have changed through the fusion of chromosomal arms followed by subsequent rearrangement events. 相似文献
277.
do Nascimento CA Lião LM Kato L da Silva CC Tanaka CM Schuquel IT de Oliveira CM 《Carbohydrate research》2008,343(6):1104-1107
A new tetrahydro beta-carboline alkaloid that has an oligosaccharide unit was isolated from the root extracts of the Palicourea coriacea. The structure was elucidated using spectral methods, including 2D NMR: COSY, HMQC, HMBC and NOESY. 相似文献
278.
Pinheiro ES Silva IM Gonzaga LV Amante ER Teófilo RF Ferreira MM Amboni RD 《Bioresource technology》2008,99(13):5561-5566
A central composite design was employed to optimize the extraction of pectin with citric acid. The independent variables were citric acid concentration (0.086–2.91% w/v) and extraction time (17–102 min). The combined effect of these variables on the degree of esterification was investigated. Results have shown that the generated regression models adequately explained the data variation and significantly represented the actual relationship between the independent variables and the responses. Besides that, the citric acid concentration was the most important factor to affect the degree of esterification, as it exerted a significant influence on the dependent variable. Lower citric acid concentration increased the pectin degree of esterification. The surface response showed the relationships between the independent variables, and thus responses were generated. Through this surface, the satisfactory condition of 0.086% w/v citric acid for 60 min was established for extraction of high-ester yellow passion fruit pectin. 相似文献
279.
Claudio Maffeis Yves Schutz Lorenza Chini Alessandra Grezzani Rita Piccoli Luciano Tat 《Obesity (Silver Spring, Md.)》2004,12(7):1128-1135
Objective: To see whether a fat‐rich (50%) evening meal promoted fat oxidation and a different spontaneous food intake on the following day at breakfast than a meal with a lower fat content (20%) in 10 prepubertal obese girls. Research Methods and Procedures: The postabsorptive and postprandial (10.5 hours) energy expenditure after a low‐fat (LF) (20% fat, 68% carbohydrate, 12% protein) and an isocaloric (2.1 MJ) and isoproteic high‐fat (HF; 50% fat, 38% carbohydrate, 12% protein) meal were measured by in direct calorimetry. Results: Fat oxidation was not significantly different after the two meals [LF, 31 ± 9 vs. HF, 35 ± 9 g/10.5 hours, p = not significant (NS)]. The girls oxidized 1.8 ± 0.9 times more fat than that ingested (11.1 grams) with the LF meal vs. 0.3 ± 0.3 times more fat than that ingested (27.1 grams) with the HF meal (p < 0.001). Carbohydrate oxidation was significantly higher after an LF than an HF meal (39 ± 12 vs. 29 ± 9 g/10.5 hours, p < 0, 05). At breakfast, the girls spontaneously ingested a similar amount of energy (1.5 ± 0.7 vs. 1.5 ± 0.6 MJ, p = NS) and macronutrient proportions (fat, 23% vs. 26%, p = NS; protein, 9% vs. 10%; carbohydrate, 68% vs. 64%,) independently of their having eaten an HF or an LF dinner. Discussion: An HF dinner did not stimulate fat oxidation, and no compensatory effect in spontaneous food intake was observed during breakfast the following morning. Cumulated total fat oxidation after dinner was higher than total fat ingested at dinner, but a much larger negative fat balance was observed after the LF meal. Spontaneous energy and nutrient intakes at breakfast were similar after LF and HF isocaloric, isoproteic dinners. This study points out the lack of sensitivity of short‐term fat balance to subsequently readjust fat intake and emphasizes the importance of an LF meal to avoid transient positive fat imbalance. 相似文献
280.
Fabrizio Bolletta Marco Montalti Silvia Romano Luciano Canovese Claudio Santo 《Inorganica chimica acta》2004,357(14):4078-4084
Two new fluorescent chemosensors for heavy metal ions have been synthesised and their photophysical properties have been investigated. They present a pyridyl-thioether-based binding site and the anthracene moiety as a chromophore. In the experimental conditions used, no evidence is found for the formation of complexes with Pb2+, Zn2+, Cd2+, and Ag+ ions. On the contrary, in acetonitrile solutions both ligands strongly bind Cu2+ and Hg2+ cations according to a 1:1 and a 1:2 (metal:ligand) stoichiometry. In these complexes, the intense luminescence typical of anthracene derivatives is almost completely quenched and this phenomenon can be mainly attributed to an intraligand electron transfer process from the anthracene chromophore to the complexed pyridine. These results are of interest for the development of new chemosensors for the design of efficient electronic tongues for the detection of transition metal ions. 相似文献