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71.
Danilo ML Prado Fabiana B Benatti Ana L de Sá-Pinto Ana P Hayashi Bruno Gualano Rosa MR Pereira Adriana ME Sallum Eloisa Bonfá Clovis A Silva Hamilton Roschel 《Arthritis research & therapy》2013,15(2):R46
Introduction
Exercise training has emerged as a promising therapeutic strategy to counteract physical dysfunction in adult systemic lupus erythematosus. However, no longitudinal studies have evaluated the effects of an exercise training program in childhood-onset systemic lupus erythematosus (C-SLE) patients. The objective was to evaluate the safety and the efficacy of a supervised aerobic training program in improving the cardiorespiratory capacity in C-SLE patients.Methods
Nineteen physically inactive C-SLE patients were randomly assigned into two groups: trained (TR, n = 10, supervised moderate-intensity aerobic exercise program) and non-trained (NT, n = 9). Gender-, body mass index (BMI)- and age-matched healthy children were recruited as controls (C, n = 10) for baseline (PRE) measurements only. C-SLE patients were assessed at PRE and after 12 weeks of training (POST). Main measurements included exercise tolerance and cardiorespiratory measurements in response to a maximal exercise (that is, peak VO2, chronotropic reserve (CR), and the heart rate recovery (ΔHRR) (that is, the difference between HR at peak exercise and at both the first (ΔHRR1) and second (ΔHRR2) minutes of recovery after exercise).Results
The C-SLE NT patients did not present changes in any of the cardiorespiratory parameters at POST (P > 0.05). In contrast, the exercise training program was effective in promoting significant increases in time-to-exhaustion (P = 0.01; ES = 1.07), peak speed (P = 0.01; ES = 1.08), peak VO2 (P = 0.04; ES = 0.86), CR (P = 0.06; ES = 0.83), and in ΔHRR1 and ΔHRR2 (P = 0.003; ES = 1.29 and P = 0.0008; ES = 1.36, respectively) in the C-SLE TR when compared with the NT group. Moreover, cardiorespiratory parameters were comparable between C-SLE TR patients and C subjects after the exercise training intervention, as evidenced by the ANOVA analysis (P > 0.05, TR vs. C). SLEDAI-2K scores remained stable throughout the study.Conclusion
A 3-month aerobic exercise training was safe and capable of ameliorating the cardiorespiratory capacity and the autonomic function in C-SLE patients.Trial registration
NCT01515163. 相似文献72.
73.
Ontario is home to a sizeable, recently established immigrant population whose cancer mortality has until now remained unexamined. The province''s six largest immigrant groups (British, Italian, German, Dutch, Polish and Soviet) were investigated to compare their cancer mortality experience with that prevailing in Ontario and in their countries of birth for the period 1969 through 1973. Standardized mortality ratios (SMRs) were computed from data from Statistics Canada and the World Health Organization (for 1971) for five sites of cancer. The rates of death from stomach cancer were significantly higher for the immigrant groups (except the Germans) than for the Canadian-born (SMRs 158.6 to 256.1) and were significantly lower for the immigrants (except the Dutch) than for the populations of their countries of birth (SMRs 26.5 to 72.9). The rates of death from colorectal cancer and cancer of the breast tended to be lower among the immigrants. Most male immigrants had high rates of death from lung cancer relative to the Canadian-born, whereas their female counterparts had relatively low rates. For most of the immigrant groups the rates of death from prostate cancer closely resembled those prevailing in the country of birth. Displacement of cancer mortality experience towards that in Ontario was most evident for Polish immigrants. It may have been too soon to see trends among the more recent immigrants (Italian, German and Dutch), who, for the most part, had not yet reached the age of highest cancer risk. Ontario should provide a valuable resource for further studies of lifestyle and environmental determinants of cancer. 相似文献
74.
The Development of Multi-epitope Vaccines: Epitope Identification, Vaccine Design and Clinical Evaluation 总被引:5,自引:0,他引:5
A. Sette B. Livingston D. McKinney E. Appella J. Fikes J. Sidney M. Newman R. Chesnut 《Biologicals》2001,29(3-4):271-276
We have developed efficient methods for epitope identification and vaccine design. Our process for epitope selection based on the combined use of motif analyses, binding assays and immunogenicity evaluations is described. We also describe how the projected population coverage and vaccine design can be optimized. Finally, it is discussed how vaccine potency is evaluated by immunogenicity and antigenicity assays. 相似文献
75.
76.
Single nucleotide polymorphisms (SNPs) in the estrogen receptor gene and breast cancer susceptibility 总被引:8,自引:0,他引:8
Schubert EL Lee MK Newman B King MC 《The Journal of steroid biochemistry and molecular biology》1999,71(1-2):21-27
In order to evaluate the role of inherited variation in the estrogen receptor (ESR1) gene in human breast cancer, we determined intronic sequences flanking each ESRI exon; identified multiple SNPs and length polymorphisms in the ESR1 coding sequence, splice junctions and regulatory regions; and genotyped families at high risk of breast cancer and population-based breast cancer patients and controls. Of 10 polymorphic sites in ESR1, four are synonymous SNPs, two are nonsynonymous SNPs and four are length polymorphisms; five are novel. No ESR1 polymorphisms were associated with breast cancer, either in the high-risk families or the case-control study. We therefore conclude that inherited genetic variation is not a mechanism by which the estrogen receptor is commonly involved in breast cancer development. 相似文献
77.
Henry LK Field JR Adkins EM Parnas ML Vaughan RA Zou MF Newman AH Blakely RD 《The Journal of biological chemistry》2006,281(4):2012-2023
In previous studies examining the structural determinants of antidepressant and substrate recognition by serotonin transporters (SERTs), we identified Tyr-95 in transmembrane segment 1 (TM1) of human SERT as a major determinant of binding for several antagonists, including racemic citalopram ((RS)-CIT). Here we described a separate site in hSERT TM3 (Ile-172) that impacts (RS)-CIT recognition when switched to the corresponding Drosophila SERT residue (I172M). The hSERT I172M mutant displays a marked loss of inhibitor potency for multiple inhibitors such as (RS)-CIT, clomipramine, RTI-55, fluoxetine, cocaine, nisoxetine, mazindol, and nomifensine, whereas recognition of substrates, including serotonin and 3,4-methylenedioxymethamphetamine, is unaffected. Selectivity for antagonist interactions is evident with this substitution because the potencies of the antidepressants tianeptine and paroxetine are unchanged. Reduced cocaine analog recognition was verified in photoaffinity labeling studies using [(125)I]MFZ 2-24. In contrast to the I172M substitution, other substitutions at this position significantly affected substrate recognition and/or transport activity. Additionally, the mouse mutation (mSERT I172M) exhibits similar selective changes in inhibitor potency. Unlike hSERT or mSERT, analogous substitutions in mouse dopamine transporter (V152M) or human norepinephrine transporter (V148M) result in transporters that bind substrate but are deficient in the subsequent translocation of the substrate. A double mutant hSERT Y95F/I172M had a synergistic impact on (RS)-CIT recognition ( approximately 10,000-fold decrease in (RS)-CIT potency) in the context of normal serotonin recognition. The less active enantiomer (R)-CIT responded to the I172M substitution like (S)-CIT but was relatively insensitive to the Y95F substitution and did not display a synergistic loss at Y95F/I172M. An hSERT mutant with single cysteine substitutions in TM1 and TM3 resulted in formation of a high affinity cadmium metal coordination site, suggesting proximity of these domains in the tertiary structure of SERT. These studies provided evidence for distinct binding sites coordinating SERT antagonists and revealed a close interaction between TM1 and TM3 differentially targeted by stereoisomers of CIT. 相似文献
78.
Genome Survey and Characterization of Endophytic Bacteria Exhibiting a Beneficial Effect on Growth and Development of Poplar Trees 总被引:1,自引:0,他引:1
Safiyh Taghavi Craig Garafola Sébastien Monchy Lee Newman Adam Hoffman Nele Weyens Tanja Barac Jaco Vangronsveld Daniel van der Lelie 《Applied and environmental microbiology》2009,75(3):748-757
The association of endophytic bacteria with their plant hosts has a beneficial effect for many different plant species. Our goal is to identify endophytic bacteria that improve the biomass production and the carbon sequestration potential of poplar trees (Populus spp.) when grown in marginal soil and to gain an insight in the mechanisms underlying plant growth promotion. Members of the Gammaproteobacteria dominated a collection of 78 bacterial endophytes isolated from poplar and willow trees. As representatives for the dominant genera of endophytic gammaproteobacteria, we selected Enterobacter sp. strain 638, Stenotrophomonas maltophilia R551-3, Pseudomonas putida W619, and Serratia proteamaculans 568 for genome sequencing and analysis of their plant growth-promoting effects, including root development. Derivatives of these endophytes, labeled with gfp, were also used to study the colonization of their poplar hosts. In greenhouse studies, poplar cuttings (Populus deltoides × Populus nigra DN-34) inoculated with Enterobacter sp. strain 638 repeatedly showed the highest increase in biomass production compared to cuttings of noninoculated control plants. Sequence data combined with the analysis of their metabolic properties resulted in the identification of many putative mechanisms, including carbon source utilization, that help these endophytes to thrive within a plant environment and to potentially affect the growth and development of their plant hosts. Understanding the interactions between endophytic bacteria and their host plants should ultimately result in the design of strategies for improved poplar biomass production on marginal soils as a feedstock for biofuels.Endophytic bacteria are bacteria that reside within the living tissue of their host plants without substantively harming it (19, 26). They are ubiquitous in most plant species, latently residing or actively colonizing the tissues. The diversity of cultivable bacterial endophytes is exhibited not only in the variety of plant species colonized but also in the many taxa involved, with most being members of common soil bacterial genera such as Enterobacter, Pseudomonas, Burkholderia, Bacillus, and Azospirillum (21, 23). Endophytic bacteria have several mechanisms by which they can promote plant growth and health. These mechanisms are of prime importance for the use of plants as feedstocks for biofuels and for carbon sequestration through biomass production. This is vital when considering the aim of improving biomass production of marginal soils, thus avoiding competition for agricultural resources, which is one of the critical socioeconomic issues of the increased use of biofuels.Like rhizosphere bacteria, endophytic bacteria have been shown to have plant growth-promoting activity that can be due to the production of phytohormones, enzymes involved in growth regulator metabolism, such as ethylene, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, auxins, indole-3-acetic acid (IAA), acetoin, 2,3-butanediol, cytokinins (3, 13-15, 20, 30), or combinations thereof. They can also improve plant growth via the fixation of nitrogen (diazotrophy) (9, 38).Typical examples of marginal soils include soils that have deteriorated due to the presence of heavy metals or organic contaminants. These are often soils with a history of industrial, military, or mining activities. Endophytic bacteria can assist their host plants in overcoming phytotoxic effects caused by environmental contamination (5, 11, 12, 36), which is of direct relevance for waste management and pollution control via phytoremediation technologies. When nonsterile poplar cuttings (Populus trichocarpa × deltoides cv. Hoogvorst) were inoculated with the endophyte Burkholderia cepacia VM1468, a derivative of B. cepacia Bu72 which possesses the pTOM-Bu61 plasmid coding for a constitutively expressed toluene degradation pathway, it was observed that in addition to decreasing the phytotoxicity and releasing toluene, strain VM1468 also considerably improved the growth of poplar trees in the absence of toluene (36). This observation, which was the first of its kind for poplar trees, prompted us to further study the poplar tree-associated beneficial endophytic bacteria in order to improve the overall performance of poplar trees, as it can enhance multiple applications, including biomass production, carbon sequestration, and phytoremediation. This was done by screening endophytic bacteria for their plant growth-promoting capabilities toward poplar trees by performing colonization studies with gfp-labeled strains, by examining their metabolic properties, and by initiating the genome sequencing of several strains. 相似文献
79.
Lipid remodeling in Rhodopseudomonas palustris TIE‐1 upon loss of hopanoids and hopanoid methylation 下载免费PDF全文
C. Neubauer N. F. Dalleska E. S. Cowley N. J. Shikuma C.‐H. Wu A. L. Sessions D. K. Newman 《Geobiology》2015,13(5):443-453
The sedimentary record of molecular fossils (biomarkers) can potentially provide important insights into the composition of ancient organisms; however, it only captures a small portion of their original lipid content. To interpret what remains, it is important to consider the potential for functional overlap between different lipids in living cells, and how the presence of one type might impact the abundance of another. Hopanoids are a diverse class of steroid analogs made by bacteria and found in soils, sediments, and sedimentary rocks. Here, we examine the trade‐off between hopanoid production and that of other membrane lipids. We compare lipidomes of the metabolically versatile α‐proteobacterium Rhodopseudomonas palustris TIE‐1 and two hopanoid mutants, detecting native hopanoids simultaneously with other types of polar lipids by electrospray ionization mass spectrometry. In all strains, the phospholipids contain high levels of unsaturated fatty acids (often >80 %). The degree to which unsaturated fatty acids are modified to cyclopropyl fatty acids varies by phospholipid class. Deletion of the capacity for hopanoid production is accompanied by substantive changes to the lipidome, including a several‐fold rise of cardiolipins. Deletion of the ability to make methylated hopanoids has a more subtle effect; however, under photoautotrophic growth conditions, tetrahymanols are upregulated twofold. Together, these results illustrate that the ‘lipid fingerprint’ produced by a micro‐organism can vary depending on the growth condition or loss of single genes, reminding us that the absence of a biomarker does not necessarily imply the absence of a particular source organism. 相似文献
80.
The relative importance of seed availability, waterdepth, and soil phosphorus (P) concentrations oncattail (Typha domingensis pers.) earlyestablishment in an Everglades wetland area wasexamined using seed bank analysis and controlledexperiments. The experiments measured seed germinationand seedling growth in tanks with cattail seedaddition subjected to two P concentrations(un-enriched vs. enriched) and water depth (saturatedvs. flooded soils). A limited seed bank (223 ± 69m2) of cattail was found in the surface soil ofthe area studied. The germination of added seeds wasinhibited under flooded conditions, and only 0.6% ofthe germination was found. In contrast,under-saturated soil conditions, a maximum of 6% and15% germination was observed in P-un-enriched andP-enriched treatments, respectively. High mortality ofseedlings occurred regardless of P treatments followinga cold spell. However, P enrichment resulted inincreased seedling growth and asexual propagation.These results suggested the importance of theconcurrence of appropriate hydrologic regimes, Penrichment, and air temperature on the recruitment ofplant species. 相似文献