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11.
Peggy CR Godschalk Mathijs P Bergman Raymond FJ Gorkink Guus Simons Nicole van den Braak Albert J Lastovica Hubert P Endtz Henri A Verbrugh Alex van Belkum 《BMC microbiology》2006,6(1):32-13
Background
Campylobacter jejuni is the predominant cause of antecedent infection in post-infectious neuropathies such as the Guillain-Barré (GBS) and Miller Fisher syndromes (MFS). GBS and MFS are probably induced by molecular mimicry between human gangliosides and bacterial lipo-oligosaccharides (LOS). This study describes a new C. jejuni-specific high-throughput AFLP (htAFLP) approach for detection and identification of DNA polymorphism, in general, and of putative GBS/MFS-markers, in particular. 相似文献12.
Christa R. Schwintzer 《American journal of botany》1983,70(7):1071-1078
The acetylene reduction assay was used to measure nonsymbiotic and symbiotic nitrogen fixation in a weakly minerotrophic peatland throughout the ice-free season. Nonsymbiotic nitrogen fixation was found in surface materials and subsurface peat. In surface materials, nitrogenase activity measured in the field contributed about 0.6 kg N ha-1 yr-1, was closely associated with Sphagnum, but was not correlated with temperature between 12 and 27 C. No cyanobacteria were found in association with Sphagnum. In subsurface peat, nitrogenase activity measured in situ contributed no more than 0.4 kg N ha-1 yr-1 and was closely correlated with temperature between 7 and 21 C. There were uncertainites in these measurements due to presence of ethylene oxidizing activity and a long time lag. Symbiotic nitrogen fixation was found only in actinomycete-induced root nodules of Myrica gale L. Legumes were absent and the few lichens present lacked nitrogenase activity. Based on acetylene reduction assays, Myrica gale fixed about 35 kg N ha-1 yr-1. Nitrogenase activity in Myrica gale showed a strong seasonal pattern which varied little during three consecutive years even though water levels varied substantially. Nitrogen input to the peatland from nonsymbiotic nitrogen fixation was only 15% the amount contributed by bulk precipitation. Symbiotic fixation, in contrast, contributed approximately six times the amount in bulk precipitation. 相似文献
13.
14.
Tjepkema J.D. Schwintzer C.R. Burris R.H. Johnson G.V. Silvester W.B. 《Plant and Soil》2000,219(1-2):285-289
Substantial enrichment of some plant parts in 15N relative to the rest of the plant is unusual, but is found in the nitrogen-fixing nodules of many legumes. A range of actinorhizal plants was surveyed to determine whether the nodules of any of them are also substantially enriched in 15N. The nonlegume Parasponia, nodulated by a rhizobium, was also included. Four of the actinorhizal genera and Parasponia were grown in N-free culture, and three actinorhizal genera were collected from the field. Nodules of Parasponia, Casuarina and Alnus were15N enriched relative to other plant parts, but only Parasponia approached the degree of enrichment found in some legume nodules. The nodules of Datisca, Myrica, Elaeagnus, Shepherdia, and Coriaria were depleted in 15N. Thus many actinorhizal nodules are depleted in 15N compared to other plant parts and enrichment is modest when it does occur. Whole plant 15N content (15N) in four actinorhizal plants and Parasponia showed a relatively narrow range of –1.41 to –1.90. Hence regardless of the degree of nodule enrichment or depletion, whole plant 15N content appears to vary little in plants grown in N-free culture. 相似文献
15.
Cristina T Fonseca Daniela M Amaral Márcia G Ribeiro Izabel CR Beserra Marília M Guimarães 《BMC endocrine disorders》2005,5(1):1-6
Background
The prevalence of diabetes mellitus is higher in individuals with Down syndrome (DS) than in the general population; it may be due to the high prevalence of obesity presented by many of them. The aim of this study was to evaluate the insulin resistance (IR) using the HOMA (Homeostasis Model Assessment) method, in DS adolescents, describing it according to the sex, body mass index (BMI) and pubertal development.Methods
15 adolescents with DS (8 males and 7 females) were studied, aged 10 to 18 years, without history of disease or use of medication that could change the suggested laboratory evaluation. On physical examination, the pubertal signs, acanthosis nigricans (AN), weight and height were evaluated. Fasting plasma glucose and insulin were analysed by the colorimetric method and RIA-kit LINCO, respectively. IR was calculated using the HOMA method. The patients were grouped into obese, overweight and normal, according to their BMI percentiles. The EPIINFO 2004 software was used to calculate the BMI, its percentile and Z score.Results
Five patients were adults (Tanner V or presence of menarche), 9 pubertal (Tanner II – IV) and 1 prepubertal (Tanner I). No one had AN. Two were obese, 4 overweight and 9 normal. Considering the total number of patients, HOMA was 1.7 ± 1.0, insulin 9.3 ± 4.8 μU/ml and glucose 74.4 ± 14.8 mg/dl. The HOMA values were 2.0 ± 1.0 in females and 1.5 ± 1.0 in males. Considering the nutritional classification, the values of HOMA and insulin were: HOMA: 3.3 ± 0.6, 2.0 ± 1.1 and 1.3 ± 0.6, and insulin: 18.15 ± 1.6 μU/ml, 10.3 ± 3.5 μU/ml and 6.8 ± 2.8 μU/ml, in the obese, overweight and normal groups respectively. Considering puberty, the values of HOMA and insulin were: HOMA: 2.5 ± 1.3, 1.4 ± 0.6 and 0.8 ± 0.0, and insulin: 13.0 ± 5.8 μU/ml, 7.8 ± 2.9 μU/ml and 4.0 ± 0.0 μU/ml, in the adult, pubertal and prepubertal groups respectively.Conclusion
The obese and overweight, female and adult patients showed the highest values of HOMA and insulin. 相似文献16.
Using circulant symmetry to model featureless objects 总被引:1,自引:0,他引:1
17.
Greiciane MS Florim Heloisa C Caldas Julio CR de Melo Maria Alice SF Baptista Ida MM Fernandes Marcela Savoldi-Barbosa Gustavo H Goldman Mario Abbud-Filho 《Arthritis research & therapy》2015,17(1)
IntroductionMicrochimeric male fetal cells (MFCs) have been associated with systemic lupus erythematosus, and published studies have further correlated MFC with lupus nephritis (LN). In the present study, we evaluated the frequency of MFC in the renal tissue of patients with LN.MethodsTwenty-seven renal biopsies were evaluated: Fourteen were from women with clinical and laboratory findings of LN, and thirteen were from controls. Genomic DNA was extracted from kidney biopsies, and the male fetal DNA was quantified using real-time quantitative polymerase chain reactions for the detection of specific Y chromosome sequences.ResultsMFCs were detected in 9 (64%) of 14 of patients with LN, whereas no MFCs were found in the control group (P = 0.0006). No differences in pregnancy history were found between patients with LN and the control group. Significantly higher amounts of MFCs were found in patients with LN with serum creatinine ≤1.5 mg/dl. Furthermore, women with MFCs had significantly better renal function at the time of biopsy (P = 0.03). In contrast, patients with LN without MFCs presented with more severe forms of glomerulonephritis (World Health Organization class IV = 60% and class V = 40%).ConclusionsOur data indicate a high prevalence of MFCs in renal biopsy specimens from women with LN, suggesting a role for MFCs in the etiology of LN. The present report also provides some evidence that MFCs could have a beneficial effect in this disease.
Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0615-4) contains supplementary material, which is available to authorized users. 相似文献18.
Kessels MM Schwintzer L Schlobinski D Qualmann B 《European journal of cell biology》2011,90(11):926-933
Coordinated functions of the actin cytoskeleton and microtubules, which need to be carefully controlled in time and space, are required for the drastic alterations of neuronal morphology during neuromorphogenesis and neuronal network formation. A key process in neuronal actin dynamics is filament formation by actin nucleators, such as the Arp2/3 complex, formins and the brain-enriched, novel WH2 domain-based nucleators Spire and cordon-bleu (Cobl). We here discuss in detail the currently available data on the roles of these actin nucleators during neuromorphogenesis and highlight how their required control at the plasma membrane may be brought about. The Arp2/3 complex was found to be especially important for proper growth cone translocation and axon development. The underlying molecular mechanisms for Arp2/3 complex activation at the neuronal plasma membrane include a recruitment and an activation of N-WASP by lipid- and F-actin-binding adaptor proteins, Cdc42 and phosphatidyl-inositol-(4,5)-bisphosphate (PIP(2)). Together, these components upstream of N-WASP and the Arp2/3 complex ensure fine-control of N-WASP-mediated Arp2/3 complex activation and control distinct functions during axon development. They are counteracted by Arp2/3 complex inhibitors, such as PICK, which likewise play an important role in neuromorphogenesis. In contrast to the crucial role of the Arp2/3 complex in proper axon development, dendrite formation and dendritic arborization was revealed to critically involve the newly identified actin nucleator Cobl. Cobl is a brain-enriched protein and uses three Wiskott-Aldrich syndrome protein homology 2 (WH2) domains for actin binding and for promoting the formation of non-bundled, unbranched filaments. Thus, cells use different actin nucleators to steer the complex remodeling processes underlying cell morphogenesis, the formation of cellular networks and the development of complex body plans. 相似文献
19.
C C Vinson M Kanashiro A M Sebbenn T CR Williams S A Harris D H Boshier 《Heredity》2015,115(2):130-139
The impact of logging and subsequent recovery after logging is predicted to vary depending on specific life history traits of the logged species. The Eco-gene simulation model was used to evaluate the long-term impacts of selective logging over 300 years on two contrasting Brazilian Amazon tree species, Dipteryx odorata and Jacaranda copaia. D. odorata (Leguminosae), a slow growing climax tree, occurs at very low densities, whereas J. copaia (Bignoniaceae) is a fast growing pioneer tree that occurs at high densities. Microsatellite multilocus genotypes of the pre-logging populations were used as data inputs for the Eco-gene model and post-logging genetic data was used to verify the output from the simulations. Overall, under current Brazilian forest management regulations, there were neither short nor long-term impacts on J. copaia. By contrast, D. odorata cannot be sustainably logged under current regulations, a sustainable scenario was achieved by increasing the minimum cutting diameter at breast height from 50 to 100 cm over 30-year logging cycles. Genetic parameters were only slightly affected by selective logging, with reductions in the numbers of alleles and single genotypes. In the short term, the loss of alleles seen in J. copaia simulations was the same as in real data, whereas fewer alleles were lost in D. odorata simulations than in the field. The different impacts and periods of recovery for each species support the idea that ecological and genetic information are essential at species, ecological guild or reproductive group levels to help derive sustainable management scenarios for tropical forests. 相似文献
20.
Development and characterization of highly polymorphic long TC repeat microsatellite markers for genetic analysis of peanut 总被引:4,自引:0,他引:4
Selma E Macedo Márcio C Moretzsohn Soraya C M Leal-Bertioli Dione MT Alves Ediene G Gouvea Vania CR Azevedo David J Bertioli 《BMC research notes》2012,5(1):1-10