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961.
962.
Baeta-Hall L Céu Sàágua M Lourdes Bartolomeu M Anselmo AM Fernanda Rosa M 《Bioresource technology》2005,96(1):69-78
In this study, the composting performance of two olive oil husk piles was compared using two different aeration processes: aeration by mechanical turning or by forced air-injection. The results showed that after the maturation phase both piles had a similar chemical composition and the same level of organic matter degradation (around 55%). However, the time necessary to reach the thermophilic phase was shorter for the turned pile (2 months in comparison to 3 months for the air-injected pile) and the humification degree achieved was slightly higher (94% versus 83%). Both piles showed the presence of an active microbial community, with an increase by 2-3 orders of magnitude in the number of cultured microbial colonies during the composting process. No significant difference in quantitative or qualitative terms was found in the microbial populations of both piles, nor was a clear succession between a mesophilic and a thermophilic population observed. In terms of industrial application, the mechanical turning process seems to be better since it is a lower energy and time consuming process. 相似文献
963.
964.
Tinahones FJ Gómez-Zumaquero JM Garrido-Sánchez L García-Fuentes E Rojo-Martínez G Esteva I Ruiz de Adana MS Cardona F Soriguer F 《Journal of lipid research》2005,46(3):452-457
Most studies of antibodies to oxidized LDL have been undertaken in patients with different diseases and cardiovascular risk factors. However, very few studies have researched the distribution and determining factors of antibodies to oxidized LDL in the general population. A total of 1,354 persons (817 females and 537 males) aged 5-65 years were included in this study. They were selected randomly from the population census of Málaga, in southern Spain. The females had lower levels of total cholesterol and triglycerides and higher levels of HDL-cholesterol and a very significant increase (P < 0.0001) in levels of anti-oxidized LDL [low density lipoprotein modified by malondialdehyde (MDA-LDL)] antibodies but no difference in levels of immune complexes consisting of LDL and IgG antibodies (anti-LDL immune complex). Younger persons (16-35 years) had higher levels of anti-oxidized LDL (MDA-LDL) antibodies than persons older than 35 years (P = 0.05). Levels of immune complexes were significantly higher (P = 0.05) in persons aged 5-15 years than in persons older than 40 years. A very weak association was found between levels of anti-oxidized LDL (MDA-LDL) antibodies and anti-LDL immune complexes. The higher prevalence of anti-oxidized LDL (MDA-LDL) antibodies in females and young persons is in agreement with studies that found an inverse association between atherosclerosis and the level of these antibodies. 相似文献
965.
Fujiwara K Poikonen K Aleman L Valtavaara M Saksela K Mayer BJ 《Biochemistry》2002,41(42):12729-12738
Protein-protein interactions play a critical role in cellular processes such as signal transduction. Although many methods for identifying the binding partners of a protein of interest are available, it is currently difficult or impossible to assess the functional consequences of a specific interaction in vivo. To address this issue, we propose to modify proteins by addition of an artificial protein binding interface, thereby forcing them to interact in the cell in a pairwise fashion and allowing the functional consequences to be determined. For this purpose, we have developed an artificial binding interface consisting of a anti-Myc single-chain antibody (ScFv) and its peptide epitope. We found that the binding of an ScFv derived from anti-Myc monoclonal antibody 9E10 was relatively weak in vivo, so we selected an improved clone, 3DX, by in vitro mutagenesis and phage display. 3DX bound well to its epitope in a yeast two-hybrid system, and GST-fused 3DX also bound to several Myc-tagged proteins in mammalian cells. In vivo binding was relatively insensitive to the position of the ScFv in a fusion protein, but was improved by including multiple tandem copies of the Myc epitope in the binding partner. To test the system, we successfully replaced the SH3 domain-mediated interaction between the Abl tyrosine kinase and adaptor proteins Crk and Nck with an engineered interaction between 3DX and multiple Myc tags. We expect that this approach, which we term a functional interaction trap, will be a powerful proteomic tool for investigating protein-protein interactions. 相似文献
966.
Padilla O Pujana MA López-de la Iglesia A Gimferrer I Arman M Vilà JM Places L Vives J Estivill X Lozano F 《Immunogenetics》2002,54(9):621-634
The scavenger receptor cysteine-rich superfamily (SRCR-SF) is a highly conserved group of membrane and/or secreted proteins related to the innate and adaptive immune system. Here, we report the cloning of the gene encoding human S4D-SRCRB, a novel soluble member of the SRCR-SF, which is composed of four group B SRCR domains separated by Pro-, Ser- and Thr-rich polypeptides. The longest cDNA sequence found is 2,806 bp in length and encodes a mature protein of 528 aa, with a predicted molecular mass of M(r) 55,600. The S4D-SRCRB gene is located at Chromosome 7q11.23, telomeric to the Williams-Beuren syndrome deletion. It extends over 20 kb and consists of 11 exons, with each SRCR domain being encoded by a single exon. Northern blot analysis indicated that S4D-SRCRB has a broad tissue distribution and is expressed as two major mRNA species: one of 2.8 kb, with a restricted tissue expression pattern (mainly kidney and placenta), and another of 1.5 kb, with a broader distribution. A similar mRNA expression pattern was observed during the analysis of several tumor cell lines. The highest degree of similarity found between S4D-SRCRB and other group B SRCR-SF members was with human DMBT1 (a mosaic protein composed of fourteen SRCR domains, which is involved in innate defense and epithelia polarization) and chicken 18-B (a turpentine-induced soluble acute-phase protein composed of four SRCR domains). Our data indicate that S4D-SRCRB constitutes a novel SRCR-SF member, which could be involved in basic homeostatic functions such as innate host defense. 相似文献
967.
Several studies have suggested that dietary supplementation with antioxidants can influence the response to chemotherapy as well as the development of adverse side effects that result from treatment with antineoplastic agents. The emphasis of the present study was to investigate whether the administration of a single dose of oral glutamine had any protective effect against cisplatin-induced clastogenicity. Cisplatin was administered to Wistar rats either alone or after treatment with glutamine. The rats were treated with glutamine (300 mg/kg b.w.) by gavage 24h before the administration of cisplatin (5mg/kg b.w., i.p.) and then sacrificed 24h after treatment with cisplatin. Glutamine significantly reduced (by about 48%) the clastogenicity of cisplatin in rat bone marrow cells. The antioxidant action of glutamine presumably modulates the clastogenic action of cisplatin. 相似文献
968.
969.
Gude L Fernández MJ Grant KB Lorente A 《Bioorganic & medicinal chemistry letters》2002,12(21):3135-3139
Synthesis of two (2,2'-bipyridine)platinum(II) complexes tethered to one or two acridine chromophores is reported. These acridine complexes efficiently unwind and photocleave supercoiled plasmid DNA under physiological conditions of temperature and pH. 相似文献
970.
Camorlinga-Ponce M Aviles-Jimenez F Cabrera L Hernández-Pando R Muñoz O Soza J Torres J 《Helicobacter》2003,8(5):554-560
Background. Few reports exist on inflammation and interleukin (IL)‐8 response in H. pylori‐infected children. The aim of this study was to determine the intensity of inflammation, density of colonization and magnitude of IL‐8 response in children with and without H. pylori infection. Materials and Methods. We studied 45 children with dyspeptic symptoms, 21 infected with H. pylori and 24 without infection. Antrum and corpus gastric biopsies were obtained and studied for H. pylori infection with an immunofluorescence technique and for IL‐8 with an immunohistochemical assay. Biopsy specimens were stained with hematoxilin and eosin and gastritis was graded according to the Sydney system. The magnitudes of the IL‐8 response and H. pylori colonization were estimated microscopically with image analyzer software. Results. In H. pylori‐infected children, mild mono‐nuclear cell infiltration was found in 50%, and no neutrophils in 40% of cases. In the antrum but not in the corpus, the intensity of colonization correlated with neutrophil and mononuclear cell infiltration. The IL‐8 response was significantly higher in the antrum (p < .05) and corpus (p < .02) of infected children, and was localized mainly in the surface and crypts of the epithelium. No correlation was found between the magnitude of the IL‐8 response and the infiltration of either neutrophil or mononuclear cells. Conclusions. In H. pylori‐infected children, poor mononuclear and neutrophil infiltration was observed. Infection was associated with a higher IL‐8 response by gastric epithelial cells. The density of colonization but not the IL‐8 response correlated with neutrophil cell infiltration. 相似文献