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981.
High-throughput methods for detecting protein interactions, such as mass spectrometry and yeast two-hybrid assays, continue to produce vast amounts of data that may be exploited to infer protein function and regulation. As this article went to press, the pool of all published interaction information on Saccharomyces cerevisiae was 15,143 interactions among 4,825 proteins, and power-law scaling supports an estimate of 20,000 specific protein interactions. To investigate the biases, overlaps, and complementarities among these data, we have carried out an analysis of two high-throughput mass spectrometry (HMS)-based protein interaction data sets from budding yeast, comparing them to each other and to other interaction data sets. Our analysis reveals 198 interactions among 222 proteins common to both data sets, many of which reflect large multiprotein complexes. It also indicates that a "spoke" model that directly pairs bait proteins with associated proteins is roughly threefold more accurate than a "matrix" model that connects all proteins. In addition, we identify a large, previously unsuspected nucleolar complex of 148 proteins, including 39 proteins of unknown function. Our results indicate that existing large-scale protein interaction data sets are nonsaturating and that integrating many different experimental data sets yields a clearer biological view than any single method alone. 相似文献
982.
To better understand the outcomes of companion animal adoptions, Bardsley & Neidhart Inc. conducted a series of 3 surveys over a 1-year period with dog and cat owners who had adopted their pet through either a (a) Luv-A-Pet location, (b) Adopt-a-thon, or (c) traditional shelter. This article suggests opportunities to improve owners' perceptions of their pets and the adoption process through (a) providing more information before adoption about pet health and behaviors, (b) providing counseling to potential adopters to place pets appropriately, and (c) educating adopters to promote companion animal health and retention. Results demonstrate that the pet's relationship to the family unit, such as where the pet sleeps and how much time is spent with the pet, is related to the amount of veterinary care the companion animal receives, and to long-term retention. Satisfaction and retention are attributed to the pet's personality, compatibility, and behavior, rather than demographic differences among adopters or between adoption settings. The age of the companion animal at adoption, the intended recipient, and presence of children in the home also play a role. Health problems were an issue initially for half of all adopted pets, but most were resolved within 12 months. Roughly one fourth of adopters who no longer have their companion animal said their pet died. Characteristics of pets that died support the contention that spaying and neutering profoundly affects a companion animal's life span. Although retention is similar for dogs and cats, mortality is higher among cats in the first year after adoption. 相似文献
983.
Dapas B Perissin L Pucillo C Quadrifoglio F Scaggiante B 《Antisense & nucleic acid drug development》2002,12(4):247-255
Aptameric GT oligomers are a new class of potential anticancer molecules that inhibit the growth of human cancer cell lines by binding to specific nuclear proteins. We demonstrated that an aptameric GT oligonucleotide increased the therapeutic index of doxorubicin and vinblastine in T lymphoblastic drug-sensitive and multidrug-resistant (MDR) cells. The doxorubicin ID50 decreased 6.5-fold by coadministration of 1 microM GT to CCRF-CEM cells and by 24-fold by coadministration of 0.75 microM GT to CEM-VLB300 cells. In CEM-VLB300 cells, the vinblastine ID50 decreased 11-fold by coadministration of 0.5 microM GT. Control CT sequence did not potentiate the drugs in either CCRF-CEM or CEM-VLB300 cells. The ability of GT to bind to specific nuclear proteins in cancer cells related to the increase in the therapeutic index of doxorubicin and vinblastine. No cooperation was detected by the administration of GT oligomer together with doxorubicin to rat differentiated thyroid FRTL-5 cells and to normal human lymphocytes. These cells did not show binding of GT to the specific nuclear proteins, and they were not sensitive to the cytotoxic action of the GT sequence. Drug potentiation by GT not involving normal human lymphocytes might be exploited to develop a more selective treatment of drug-sensitive and MDR tumors. 相似文献
984.
Cuzzocrea S Mazzon E Dugo L Serraino I Di Paola R Genovese T De Sarro A Caputi AP 《European cytokine network》2002,13(3):285-297
Interleukin-10 (IL-10) exerts a wide spectrum of regulatory activities in the immune and inflammatory response. The aim of this study was to investigate the role of endogenous IL-10 on the modulation of the inflammatory response in mice subjected to carrageenan-induced lung injury. When compared to carrageenan-treated IL-10 wild-type (WT) mice, carrageenan-treated IL-10 knock-out mice (IL-10KO) mice experienced a higher rate of pleural exudation, and polymorphonuclear cell migration. Exudate levels of the pro-inflammatory cytokines tumour necrosis factor, interleukin-1beta and interleukin-6 were also greatly enhanced in IL-10KO mice in comparison to wild-type mice. Lung myeloperoxidase (MPO) activity was significantly reduced in IL-10WT mice when compared to IL-10KO mice-treated with carrageenan. The degree of oxidative and nitrosative damage was significantly higher in IL-10KO mice than in wild-type littermates, as indicated by elevated malondialdehyde levels and formation of nitrotyrosine and poly (ADP-ribose) synthetase (PARS). Staining of lung tissue sections obtained from carrageenan-treated IL-10WT with an anti-COX-2 antibody showed a positive staining of the inflamed tissue. Furthermore, expression of inducible nitric oxide synthase (iNOS) was found mainly in the macrophages of the inflamed lungs from carrageenan-treated IL-10WT mice. The intensity and degree of the staining for COX-2 and iNOS were markedly enhanced in tissue sections obtained from carrageenan-treated IL-10KO mice. Most notably, the degree of lung injury caused by carrageenan was also enhanced in IL-10KO mice. Taken together, our results clearly demonstrate that endogenous IL-10 exerts an anti-inflammatory role during acute inflammation and tissue damage associated with carrageenan-induced pleurisy, possibly by regulating neutrophil recruitment, and the subsequent cytokine and oxidant generation. 相似文献
985.
Brambilla G Civitareale C Ballerini A Fiori M Amadori M Archetti LI Regini M Betti M 《Redox report : communications in free radical research》2002,7(3):159-163
In pigs, the genetic selection for lean, large muscle blocks and fast growth has been linked to an increased prevalence of metabolic diseases such as porcine stress syndrome and mulberry heart disease. These diseases are associated with cardiovascular inadequacy, which may lead to oxidative stress. In the present study, reactive oxygen metabolites (ROMs) and the anti-oxidant power (OXY) in sera of different swine groups were investigated. The following groups were selected (each around 80 kg body weight): wild boars (WB), Cinta Senese (CS), and Landrace x Large White (LxLW), the latter as both specific pathogen-free (SPF) and intensively farmed animals. In addition, a group of LxLW agonic sows (AS) was also investigated; this group is known to be under oxidative stress. Two colorimetric micro-methods were used to measure ROMs and OXY; ROMs were expressed as mM H(2)O(2) and OXY as microM HOCl neutralised. Between groups, average ROM and OXY values were found to be significantly different by one-way ANOVA (P < 0.001). ROM levels were lower in WB (13.41 +/- 1.85) and CS (19.27 +/- 1.68), and highest in LxLW (42.00 +/- 1.36). OXY values ranged from 260.10 +/- 22.13 (WB) to 396.90 +/- 9.83 (LxLW). Only one swine group (the CS group) showed a significant, positive correlation between ROM and OXY values. The AS group even showed a negative correlation between ROM and OXY values. These results imply satisfactory environmental coping occurred only within the CS group. Results are discussed in the light of animal welfare legislation, food safety and consumers' protection. 相似文献
986.
987.
988.
Pérez-Vizcaíno F López-López JG Santiago R Cogolludo A Zaragozá-Arnáez F Moreno L Alonso MJ Salaices M Tamargo J 《American journal of physiology. Lung cellular and molecular physiology》2002,283(4):L839-L848
The maturation in the vasodilator response to nitric oxide (NO) in isolated intrapulmonary arteries was analyzed in newborns and 15- to 20-day-old piglets. The vasodilator responses to NO gas but not to the NO donor sodium nitroprusside increased with age. The inhibitory effects of the superoxide dismutase inhibitor diethyldithiocarbamate and xanthine oxidase plus hypoxanthine and the potentiation induced by superoxide dismutase and MnCl(2) of NO-induced vasodilatation were similar in the two age groups. Diphenyleneiodonium (NADPH oxidase inhibitor) potentiated the response to NO, and this effect was more pronounced in the older animals. The nonselective cyclooxygenase inhibitors indomethacin and meclofenamate and the preferential cyclooxygenase-1 inhibitor aspirin augmented NO-induced relaxation specifically in newborns, whereas the selective cycloxygenase-2 inhibitor NS-398 had no effect. The expressions of alpha-actin, cycloxygenase-1, and cycloxygenase-2 proteins were similar, whereas Cu,Zn-superoxide dismutase decreased with age. Therefore, the present data suggest that the maturational increase in the vasodilatation of NO in the pulmonary arteries during the first days of extrauterine life involves a cycloxygenase-dependent inhibition of neonatal NO activity. 相似文献
989.
Recombinant human histone H4 (hH4) was produced in milligrams quantities in Escherichia coli, without altering the codons of the original cDNA sequence. The hH4 cDNA was subcloned into the pQE30 expression vector, in frame with a sequence encoding an N-terminal stretch of six histidine residues. Purification to electrophoretic homogeneity was obtained by nickel-chelating chromatography, followed by gel filtration. The final yield of the entire expression and purification process was about 1 mg of pure histone H4 per liter of bacterial culture. SDS-PAGE analysis showed for the recombinant H4 a molecular weight corresponding to the expected one (12,535 Da). Circular dichroism spectroscopy was used to estimate the secondary structural composition of recombinant histone, when it is isolated from the physiological core particle. It was observed that under these conditions histone H4 exhibits an altered secondary conformation. In order to induce the recombinant histone to assume a conformation more similar to the one measured when it is organized inside the nucleosome, we resuspended it in buffers at increasing ionic strengths and in the presence of different concentrations of trifluoroethanol. We tried also to mimic the physiological situation of histone H4 by adding an equimolar amount of a commercial DNA to the protein solution. Finally, an estimation of protein thermal stability was evaluated by spectropolarimetry. 相似文献
990.
Legakis JE Koepke JI Jedeszko C Barlaskar F Terlecky LJ Edwards HJ Walton PA Terlecky SR 《Molecular biology of the cell》2002,13(12):4243-4255
The molecular mechanisms of peroxisome biogenesis have begun to emerge; in contrast, relatively little is known about how the organelle functions as cells age. In this report, we characterize age-related changes in peroxisomes of human cells. We show that aging compromises peroxisomal targeting signal 1 (PTS1) protein import, affecting in particular the critical antioxidant enzyme catalase. The number and appearance of peroxisomes are altered in these cells, and the organelles accumulate the PTS1-import receptor, Pex5p, on their membranes. Concomitantly, cells produce increasing amounts of the toxic metabolite hydrogen peroxide, and we present evidence that this increased load of reactive oxygen species may further reduce peroxisomal protein import and exacerbate the effects of aging. 相似文献