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21.
22.
Thomas K?ller Daniel Kurze Mirjam Lange Martin Scherdin Andreas Podbielski Philipp Warnke 《PloS one》2016,11(4)
A fully automated multiplex real-time PCR assay—including a sample process control and a plasmid based positive control—for the detection and differentiation of herpes simplex virus 1 (HSV1), herpes simplex virus 2 (HSV2) and varicella-zoster virus (VZV) from cerebrospinal fluids (CSF) was developed on the BD Max platform. Performance was compared to an established accredited multiplex real time PCR protocol utilizing the easyMAG and the LightCycler 480/II, both very common devices in viral molecular diagnostics. For clinical validation, 123 CSF specimens and 40 reference samples from national interlaboratory comparisons were examined with both methods, resulting in 97.6% and 100% concordance for CSF and reference samples, respectively. Utilizing the BD Max platform revealed sensitivities of 173 (CI 95%, 88–258) copies/ml for HSV1, 171 (CI 95%, 148–194) copies/ml for HSV2 and 84 (CI 95%, 5–163) copies/ml for VZV. Cross reactivity could be excluded by checking 25 common viral, bacterial and fungal human pathogens. Workflow analyses displayed shorter test duration as well as remarkable fewer and easier preparation steps with the potential to reduce error rates occurring when manually assessing patient samples. This protocol allows for a fully automated PCR assay on the BD Max platform for the simultaneously detection of herpesviridae from CSF specimens. Singular or multiple infections due to HSV1, HSV2 and VZV can reliably be differentiated with good sensitivities. Control parameters are included within the assay, thereby rendering its suitability for current quality management requirements. 相似文献
23.
Alies van Lier Scott A. McDonald Martijn Bouwknegt EPI group Mirjam E. Kretzschmar Arie H. Havelaar Marie-Josée J. Mangen Jacco Wallinga Hester E. de Melker 《PloS one》2016,11(4)
BackgroundInfectious disease burden estimates provided by a composite health measure give a balanced view of the true impact of a disease on a population, allowing the relative impact of diseases that differ in severity and mortality to be monitored over time. This article presents the first national disease burden estimates for a comprehensive set of 32 infectious diseases in the Netherlands.ConclusionsFor guiding and supporting public health policy decisions regarding the prioritisation of interventions and preventive measures, estimates of disease burden and the comparison of burden between diseases can be informative. Although the collection of disease-specific parameters and estimation of incidence is a process subject to continuous improvement, the current study established a baseline for assessing the impact of future public health initiatives. 相似文献
24.
Felix P. Bernhard Sebastian Heinzel Gerhard Binder Karin Weber Anja Apel Benjamin Roeben Christian Deuschle Mirjam Maechtel Tanja Heger Susanne Nussbaum Thomas Gasser Walter Maetzler Daniela Berg 《PloS one》2016,11(3)
Introduction
Biomarkers indicating trait, progression and prediction of pathology and symptoms in Parkinson''s disease (PD) often lack specificity or reliability. Investigating biomarker variance between individuals and over time and the effect of confounding factors is essential for the evaluation of biomarkers in PD, such as insulin-like growth factor 1 (IGF-1).Materials and Methods
IGF-1 serum levels were investigated in up to 8 biannual visits in 37 PD patients and 22 healthy controls (HC) in the longitudinal MODEP study. IGF-1 baseline levels and annual changes in IGF-1 were compared between PD patients and HC while accounting for baseline disease duration (19 early stage: ≤3.5 years; 18 moderate stage: >4 years), age, sex, body mass index (BMI) and common medical factors putatively modulating IGF-1. In addition, associations of baseline IGF-1 with annual changes of motor, cognitive and depressive symptoms and medication dose were investigated.Results
PD patients in moderate (130±26 ng/mL; p = .004), but not early stages (115±19, p>.1), showed significantly increased baseline IGF-1 levels compared with HC (106±24 ng/mL; p = .017). Age had a significant negative correlation with IGF-1 levels in HC (r = -.47, p = .028) and no correlation in PD patients (r = -.06, p>.1). BMI was negatively correlated in the overall group (r = -.28, p = .034). The annual changes in IGF-1 did not differ significantly between groups and were not correlated with disease duration. Baseline IGF-1 levels were not associated with annual changes of clinical parameters.Discussion
Elevated IGF-1 in serum might differentiate between patients in moderate PD stages and HC. However, the value of serum IGF-1 as a trait-, progression- and prediction marker in PD is limited as IGF-1 showed large inter- and intraindividual variability and may be modulated by several confounders. 相似文献25.
In rat kidney, megalin, a member of the low density lipoprotein receptor gene family, is the sole glycoprotein which carries oligo/poly 2,8 deaminoneuraminic acid (KDN) as a posttranslational modification. We have investigated immunoprecipitated megalin from rat brain, lung and placenta, mouse yolk sac carcinoma and megalin synthesizing carcinoma cell lines, for presence of this unique glycan structure. Our immunoblot analysis revealed the presence of oligo/poly 2,8 KDN on megalin in all the studied normal tissues and carcinoma cells. Furthermore, it is demonstrated that to be part of oligosaccharides O-glycosidically linked to megalin. 相似文献
26.
Phosphatidylcholine (PC), a major lipid class in the membranes of eukaryotes, is synthesized either via the triple methylation of phosphatidylethanolamine (PE) or via the CDP-choline route. To investigate whether the two biosynthetic routes contribute differently to the steady-state profile of PC species, i.e., PC molecules with specific acyl chain compositions, the pools of newly synthesized PC species were monitored by labeling Saccharomyces cerevisiae with deuterated precursors of the two routes, (methyl-D3)-methionine and (D13)-choline, respectively. Electrospray ionization tandem mass spectrometry (ESI-MS/MS) revealed that the two PC biosynthetic pathways yield different sets of PC species, with the CDP-choline route contributing most to the molecular diversity. Moreover, yeast was shown to be capable of remodeling PC by acyl chain exchange at the sn-1 position of the glycerol backbone. Remodeling was found to be required to generate the steady-state species distribution of PC. This is the first study demonstrating a functional difference between the two biosynthetic routes in yeast. 相似文献
27.
A combination of techniques was used to localise the O-acetyl substituents in xylo-oligosaccharides, which are present in hydrolysates of hydrothermally treated Eucalyptus wood. Reversed-phase (RP)-high performance liquid chromatography (HPLC) coupled on-line to both a mass spectrometer and an evaporating light scattering (ELS) detector provided data about the order of elution of the various O-acetylated oligomers. The retention of the oligomers on the column depended on the number and position of the O-acetyl substituents within the xylo-oligosaccharides. One dimensional (1D)- and two dimensional (2D)-(1)H NMR spectroscopy was used to study the structural features of several xylotetramers separated by RP-HPLC, each having one O-acetyl substituent. O-Acetyl migration was proven to have occurred in these xylo-oligosaccharides. Mainly O-acetyl migration within the same xylosyl residue was observed. RP-HPLC-NMR was performed in order to study the structural features of the acetylated oligomers 'on-line' avoiding O-acetyl migration. Finally, the precise location of the 2-O- or 3-O-acetyl substituent in 6 xylotetramers and 4 xylotrimers separated by RP-HPLC was determined. 相似文献
28.
Neff L Zeisel M Druet V Takeda K Klein JP Sibilia J Wachsmann D 《The Journal of biological chemistry》2003,278(30):27721-27728
Protein I/II, a pathogen-associated molecular pattern from oral streptococci, is a potent inducer of interleukin-6 (IL-6) and IL-8 synthesis and release from fibroblast-like synoviocytes (FLSs), cells that are critically involved in joint inflammation. This synthesis implicates ERK 1/2 and JNKs as well as AP-1-binding activity and nuclear translocation of NF-kappaB. The mechanisms by which protein I/II activates MAPKs remain, however, elusive. Because focal adhesion kinase (FAK) was proposed to play a role in signaling to MAPKs, we examined its ability to contribute to the MAPKs-dependent synthesis of IL-6 and IL-8 in response to protein I/II. We used FAK-/- fibroblasts as well as FAK+/+ fibroblasts and FLSs transfected with FRNK, a dominant negative form of FAK. The results demonstrate that IL-6 and IL-8 release in response to protein I/II was strongly inhibited in both protein I/II-stimulated FAK-/- and FRNK-transfected cells. Cytochalasin D, which inhibits protein I/II-induced phosphorylation of FAK (Tyr-397), had no effect either on activation of ERK 1/2 and JNKs or on IL-6 and IL-8 release. Taken together, these results indicate that IL-6 and IL-8 release by protein I/II-activated FLSs is regulated by FAK independently of Tyr-397 phosphorylation. 相似文献
29.
Nitric oxide synthesis is involved in arterial haptoglobin expression after sustained flow changes 总被引:4,自引:0,他引:4
Smeets MB Pasterkamp G Lim SK Velema E van Middelaar B de Kleijn DP 《FEBS letters》2002,529(2-3):221-224
The acute phase protein haptoglobin is highly expressed in arteries after sustained flow changes and involved in cell migration and arterial restructuring. In the liver, haptoglobin expression is mainly regulated by interleukin-6 (IL-6). In the artery, shear stress and NO influence IL-6 expression. In the present study, we demonstrate that NO synthesis is involved in the regulation of arterial haptoglobin expression after sustained flow changes. Decreased haptoglobin expression after NO inhibition coincided with decreased IL-6 levels. However, IL-6 knockout mice had normal arterial haptoglobin expression levels after sustained flow changes suggesting that other mediators may provide compensatory mechanisms for the regulation of arterial haptoglobin expression. 相似文献
30.
Key role for mast cells in nonatopic asthma 总被引:7,自引:0,他引:7
Kraneveld AD van der Kleij HP Kool M van Houwelingen AH Weitenberg AC Redegeld FA Nijkamp FP 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(4):2044-2053
The mechanisms involved in nonatopic asthma are poorly defined. In particular, the importance of mast cells in the development of nonatopic asthma is not clear. In the mouse, pulmonary hypersensitivity reactions induced by skin sensitization with the low-m.w. compound dinitrofluorobenzene (DNFB) followed by an intra-airway application of the hapten have been featured as a model for nonatopic asthma. In present study, we used this model to examine the role of mast cells in the pathogenesis of nonatopic asthma. First, the effect of DNFB sensitization and intra-airway challenge with dinitrobenzene sulfonic acid (DNS) on mast cell activation was monitored during the early phase of the response in BALB/c mice. Second, mast cell-deficient W/W(v) and Sl/Sl(d) mice and their respective normal (+/+) littermate mice and mast cell-reconstituted W/W(v) mice (bone marrow-derived mast cells-->W/W(v)) were used. Early phase mast cell activation was found, which was maximal 30 min after DNS challenge in DNFB-sensitized BALB/c, +/+ mice but not in mast cell-deficient mice. An acute bronchoconstriction and increase in vascular permeability accompanied the early phase mast cell activation. BALB/c, +/+ and bone marrow-derived mast cell-->W/W(v) mice sensitized with DNFB and DNS-challenged exhibited tracheal hyperreactivity 24 and 48 h after the challenge when compared with vehicle-treated mice. Mucosal exudation and infiltration of neutrophils in bronchoalveolar lavage fluid associated the late phase response. Both mast cell-deficient strains failed to show any features of this hypersensitivity response. Our findings show that mast cells play a key role in the regulation of pulmonary hypersensitivity responses in this murine model for nonatopic asthma. 相似文献