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1.
Anna M. Kauppi Alicia Edin Ingrid Ziegler Paula M?lling Anders Sj?stedt ?sa Gylfe Kristoffer Str?lin Anders Johansson 《PloS one》2016,11(1)
A metabolomics approach for prediction of bacteremic sepsis in patients in the emergency room (ER) was investigated. In a prospective study, whole blood samples from 65 patients with bacteremic sepsis and 49 ER controls were compared. The blood samples were analyzed using gas chromatography coupled to time-of-flight mass spectrometry. Multivariate and logistic regression modeling using metabolites identified by chromatography or using conventional laboratory parameters and clinical scores of infection were employed. A predictive model of bacteremic sepsis with 107 metabolites was developed and validated. The number of metabolites was reduced stepwise until identifying a set of 6 predictive metabolites. A 6-metabolite predictive logistic regression model showed a sensitivity of 0.91(95% CI 0.69–0.99) and a specificity 0.84 (95% CI 0.58–0.94) with an AUC of 0.93 (95% CI 0.89–1.01). Myristic acid was the single most predictive metabolite, with a sensitivity of 1.00 (95% CI 0.85–1.00) and specificity of 0.95 (95% CI 0.74–0.99), and performed better than various combinations of conventional laboratory and clinical parameters. We found that a metabolomics approach for analysis of acute blood samples was useful for identification of patients with bacteremic sepsis. Metabolomics should be further evaluated as a new tool for infection diagnostics. 相似文献
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The absolute concentration of zinc in the Purkinje cells of the rat cerebellum was determined by means of energy dispersive X-ray microanalysis (EDAX). Gelatine blocks with known zinc concentrations were stained by Timm's sulphide-silver method, and their silver concentrations were measured by EDAX. A linear correlation was found between the zinc and silver concentrations and this linear function was used as a quantitative calibration for evaluation of sulphide-silver staining, after perfusion with sodium-sulphide solution, fixation with glutaraldehyde, cryostat sectioning and staining of cerebellar samples in Timm's reagent. 相似文献
5.
Waicheim María Agustina Mendes Marques Taísa Rauque Carlos Alejandro Viozzi Gustavo 《Systematic parasitology》2021,98(2):131-139
Systematic Parasitology - A new parasitic copepod, Ergasilus yandemontei n. sp., is described based on 10 adult females collected from the gills of the atherinid silverside Odontesthes hatcheri... 相似文献
6.
Different types of genetic and epigenetic changes are associated with HNSCC. The molecular mechanisms of HNSCC carcinogenesis are still undergoing intensive investigation. WWOX gene expression is altered in many cancers and in a recent work reduced WWOX expression has been associated with miR-134 expression in HNSCC. In this study we investigated the WWOX messenger RNA expression levels in association with the promoter methylation of the WWOX gene and miR-134 expression levels in 80 HNSCC tumor and non-cancerous tissue samples. Our results show that WWOX expression is down-regulated especially in advanced-stage tumor samples or in tumors with SCC. This down-regulation was associated with methylation of the WWOX promoter region but not with miR-134 expression. There was an inverse correlation between the expression level and promoter methylation. We also analyzed whole exons and exon/intron boundries of the WWOX gene by direct sequencing. In our study group we observed 10 different alterations in the coding sequences and 18 different alterations in the non-coding sequences of the WWOX gene in HNSCC tumor samples. These results indicate that the WWOX gene can be functionally inactivated by promoter methylation, epigenetically or by mutations affecting the sequences coding for the enzymatic domain of the gene, functionally. We conclude that inactivation of WWOX gene contributes to the progression of HNSCC. 相似文献
7.
Carlos Alemn M. Cristina Vega Eloísa Navarro Jordi Puiggalí 《Journal of peptide science》1996,2(6):364-370
The conformational preferences of the methylenic sequence in the side chain of the glutamine residue were investigated by ab initio and semi-empirical quantum mechanical calculations and examination of both the Brookhaven Protein Databank and Cambridge Structural Data Base. The results were analysed on the basis of our previous findings about the folding of methylene groups in aliphatic segments. Both energy calculations and the crystallographic structure of small peptides indicate that methylene units of the glutamine residue tend to fold in a gauche conformation. In contrast, such groups usually adopt an all-trans conformation in proteins due basically to the entropic and solvent contributions. These results have been demonstrated by computing the entropic correction to the free energy and evaluating the solvent effects through SCRF calculations 相似文献
8.
Immobilized a-chymotrypsin was used as catalyst for studying temperature effects on acyl transfer reactions (acyl-donor: Bz-TyrOEt) in a water-immiscible organic solvent. The solubility of the two nucleophiles, Phe-NH and water, decreased with decreasing temperature. The relative decrease for the amide was larger (2.4-fold) than for water. Therefore the thermodynamic activity (estimated by the relative saturation) increased more for this substrate and hence the selectivity in the reaction was increased. 相似文献
9.
Åsa Lankinen 《Oecologia》2001,128(4):492-498
In this study on Viola tricolor pollen, the competitive ability of 16 pollen donors originating from a wild population was analysed in a set of greenhouse and germination temperatures. The aim was to examine the consistency in donor pollen performance across temperatures and to see whether variation in performance was random or due to individual differences in the plastic response to temperature. Pollen tube growth rate in vitro was investigated in two greenhouse temperatures (on the day pollen was collected) and in four germination temperatures. In addition, pollen tube growth rate was assessed in vivo (in one temperature) to examine the relationship between in vivo and in vitro growth. A temperature difference of 5 K - corresponding to natural variation in time and space detected in the field - affected pollen tube growth rate. For both temperature components, significant pollen donor by temperature interactions were found and rank order of pollen donors changed across treatments. Although pollen competitive ability in violets was strongly influenced by both temperature components, the occurrence of pollen donor by temperature interactions indicates that donor siring ability varies with temperature. This, in turn, may suggest a means to maintain pollen competitive ability despite selection for this trait. 相似文献
10.
Karina D. Asensi Rodrigo S. Fortunato Danúbia S. dos Santos Thaísa S. Pacheco Danielle F. de Rezende Deivid C. Rodrigues Fernanda C. P. Mesquita Tais H. Kasai‐Brunswick Antonio C. Campos de Carvalho Denise P. Carvalho Adriana B. Carvalho Regina C. dos S. Goldenberg 《Journal of cellular and molecular medicine》2014,18(5):824-831
Properties of induced pluripotent stem cells (iPSC) have been extensively studied since their first derivation in 2006. However, the modification in reactive oxygen species (ROS) production and detoxification caused by reprogramming still needs to be further elucidated. The objective of this study was to compare the response of iPSC generated from menstrual blood–derived mesenchymal stem cells (mb‐iPSC), embryonic stem cells (H9) and adult menstrual blood–derived mesenchymal stem cells (mbMSC) to ROS exposure and investigate the effects of reprogramming on cellular oxidative stress (OS). mbMSC were extremely resistant to ROS exposure, however, mb‐iPSC were 10‐fold less resistant to H2O2, which was very similar to embryonic stem cell sensitivity. Extracellular production of ROS was also similar in mb‐iPSC and H9 and almost threefold lower than in mbMSC. Furthermore, intracellular amounts of ROS were higher in mb‐iPSC and H9 when compared with mbMSC. As the ability to metabolize ROS is related to antioxidant enzymes, we analysed enzyme activities in these cell types. Catalase and superoxide dismutase activities were reduced in mb‐iPSC and H9 when compared with mbMSC. Finally, cell adhesion under OS conditions was impaired in mb‐iPSC when compared with mbMSC, albeit similar to H9. Thus, reprogramming leads to profound modifications in extracellular ROS production accompanied by loss of the ability to handle OS. 相似文献