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101.
Lund TC Stadem PS Panoskaltsis-Mortari A Raymond G Miller WP Tolar J Orchard PJ 《PloS one》2012,7(2):e32218
Background
X-linked adrenoleukodystrophy (ALD) is a metabolic, peroxisomal disease that results from a mutation in the ABCD1 gene. The most severe course of ALD progression is the cerebral inflammatory and demyelinating form of the disease, cALD. To date there is very little information on the cytokine mediators in the cerebral spinal fluid (CSF) of these boys.Methodology/Principal Findings
Measurement of 23 different cytokines was performed on CSF and serum of boys with cerebral ALD and patients without ALD. Significant elevations in CSF IL-8 (29.3±2.2 vs 12.8±1.1 pg/ml, p = 0.0001), IL-1ra (166±30 vs 8.6±6.5 pg/ml, p = 0.005), MCP-1 (610±47 vs 328±34 pg/ml, p = 0.002), and MIP-1b (14.2±1.3 vs 2.0±1.4 pg/ml, p<0.0001) were found in boys with cALD versus the control group. The only serum cytokine showing an elevation in the ALD group was SDF-1 (2124±155 vs 1175±125 pg/ml, p = 0.0001). The CSF cytokines of IL-8 and MCP-1b correlated with the Loes MRI severity score (p = 0.04 and p = 0.008 respectively), as well as the serum SDF-1 level (p = 0.002). Finally, CSF total protein was also significantly elevated in boys with cALD and correlated with both IL-8, MCP-1b (p = 0.0001 for both), as well as Loes MRI severity score (p = 0.0007).Conclusions/Significance
IL-8, IL-1ra, MCP-1, MIP-1b and CSF total protein were significantly elevated in patients with cALD; IL-8, MCP-1b, and CSF total protein levels correlated with disease severity determined by MRI. This is the largest report of CSF cytokine levels in cALD to date, and identification of these key cytokines will provide further insight into disease progression and perhaps lead to improved targeted therapies. 相似文献102.
Common and distinct patterns of terminal modifications to mirtrons and canonical microRNAs 总被引:1,自引:0,他引:1
Nucleotide modifications to microRNAs or their precursors can influence their processing and/or activity. A challenge to their analysis is the lack of independent references for the termini generated by primary processing; typically, these are empirically assigned as the most abundant mapped reads. Mirtrons offer such an independent measure since these microRNA hairpins are defined by splicing. Consequently, mirtron-derived reads that deviate from splice sites reflect modification following primary processing. Analysis in Drosophila revealed multiple modification patterns, including select alterations of 5' termini, many 3' resection events, and unexpectedly abundant 3' untemplated monouridylation. Resections occur on mature AGO1-loaded species, whereas uridylation occurs on pre-miRNAs but is compatible with dicing and AGO1 loading. Strikingly, we found many mirtrons whose modified reads are more abundant than those produced by primary processing. In some cases, these abundant modified reads matched the genome owing to fortuitous uridines in downstream flanking exons, thus highlighting the value of an independent reference for the primary-processed sequence. We could further extend the principle of abundant and preferred uridylation of mirtrons, relative to canonical pre-miRNAs, to Caenorhabditis elegans, mouse, and human. Finally, we found that 3' resection occurs broadly across AGO1-loaded canonical miRNA and star species. Altogether, these findings substantially broaden the complexity of terminal modification pathways acting upon small regulatory RNAs. 相似文献
103.
We developed predictive maps of farmland and forest species richness which are based on the “focal species concept” and remote sensing data. We explored environmental preferences of 17 farmland and 33 forest species in Poland, using data from the Pan-European Monitoring Scheme. The largest number of farmland species was noted in the central and eastern parts, while the opposite trend was observed in the case of forest species, where the preferred areas were in the north and south-east. The most important environmental component affecting the bird faunas of farmland and forest was a gradient from arable fields to forest. This relationship is unimodal, which means that on a meso-geographical scale the highest species richness occurred in heterogeneous landscapes where fields are interspersed with forest. Our results also indicate that the geographical gradient in Poland's bird fauna can simply be attributed to the habitat-based distinction: western and central parts are dominated by large agricultural habitats and coniferous forest, while in other areas predominate mixed forests and extensively used farmland. Among the climatic factors, only rainfall influenced the farmland bird species. Its effect is non-linear, but positive, which means that in areas with higher rainfall more species are recorded.Our predictive maps are complementary to research on population trends, and can be an essential tool for effective management and conservation of species populations on a trans-national scale. 相似文献
104.
105.
B Ruszczycki Z Szepesi G Wilczynski M Bijata K Kalita L Kaczmarek J Wlodarczyk 《BMC bioinformatics》2012,13(1):213
ABSTRACT: BACKGROUND: Quantitative analysis of changes in dendritic spine morphology has become an interesting issue in contemporary neuroscience. However, the diversity in dendritic spines population might seriously influence the results of measurements in which their morphology is studied, the detection of differences in spine morphology between control and test group is often compromised by the number of dendritic spines taken for analysis. In order to estimate how severe is such an impact we have performed Monte Carlo simulations examining various experimental setups and statistical approaches. The confocal images of dendritic spines from hippocampal dissociated cultures have been used to create a set of variables exploited as the simulation resources. RESULTS: The tabulated results of simulations are given, providing the number of dendritic spines required for the detection of hidden morphological differences between control and test group, in spine head-width, length and area. It turns out that this is the head-width among these three variables, where the changes are most easily detected. Simulation of changes occurring in a subpopulation of spines reveal the strong dependence of detectability on the statistical approach applied. The analysis based on comparison of percentage of spines in subclasses is less sensitive than the direct comparison of relevant variables describing spines morphology. CONCLUSIONS: We evaluated the sampling aspect and effect of systematic morphological variation on detecting the differences in spine morphology. Provided results may serve as a guideline in selecting the number of samples to be studied in a planned experiment. Our simulations might be a step towards the development of a standardized method of quantitative comparison of dendritic spines morphology, in which different sources of errors are considered. 相似文献
106.
107.
We present a new approach to surface plasmon microscopy with high refractive index sensitivity and spatial resolution that is not limited by the propagation length of surface plasmons. It is based on a nanostructured metallic sensor surface supporting Bragg-scattered surface plasmons. We show that these non-propagating surface plasmon modes are excellently suited for spatially resolved observations of refractive index variations on the sensor surface owing to their highly confined field profile perpendicular to as well as parallel to the metal interface. The presented theoretical study reveals that this approach enables reaching similar refractive index sensitivity as regular surface plasmon resonance (SPR) microscopy and offers the advantage of improved spatial resolution when observing dielectric features with lateral size <10???m for the wavelength around 800?nm and gold as the SPR-active metal. This paper demonstrates the potential of Bragg-scattered surface plasmon microscopy for high-throughput SPR biosensing with high-density microarrays. 相似文献
108.
109.
Jablonska E Jablonski J Marcinczyk M Grabowska Z Piotrowski L 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2008,46(2):177-183
In the present study we examined the release of the soluble form of TRAIL by neutrophils (PMN) derived from patients with oral cavity cancer. Simultaneously, we estimated the ability of PMNs of these patients to release the soluble form of DR5 receptor, a natural regulatory protein of TRAIL. The obtained results were confronted with the serum levels of sTRAIL and sDR5. The cells were isolated from 21 patients with squamous cell carcinoma of oral cavity at diagnosis and three weeks after surgery treatment. For comparative purposes we performed similar examinations in autologous peripheral blood mononuclear cells (PBMC). Cytoplasmic protein fractions of the cells were analyzed for the presence of TRAIL and DR5 by western blotting. Soluble TRAIL and soluble DR5 concentrations in the culture supernatants of cells were confronted with their serum levels using ELISA kit. PMN and PBMC of the whole cancer patient group expressed decreased TRAIL protein and unchanged expression of DR5 receptor in comparison with the control group. Unchanged release of sTRAIL by PMNs of patients in Stage II was accompanying the decrease of the ability of PBMC to secrete this protein. In patients in Stage IV the secretion of sTRAIL by PMNs and PBMC was impaired. In contrast to changes in sTRAIL secretion by PMN and PBMC of oral cavity cancer patients, the secretion of sDR5 by these cells was unchanged. The serum levels of sTRAIL were increased in patients in Stage II before treatment and decreased in the same patients after treatment. The altered ability of PMN of PBMC to secrete sTRAIL may have different implications for the immune response of patients with oral cavity cancer cells at different stages of disease. 相似文献
110.
Chlorosomes of green photosynthetic bacterium Chlorobium tepidum contain aggregates of bacteriochlorophyll c (BChl c) with carotenoids and isoprenoid quinones. BChl aggregates with very similar optical properties can be prepared also in vitro
either in non-polar solvents or in aqueous buffers with addition of lipids and/or carotenoids. In this work, we show that the aggregation of BChl c in aqueous buffer can be induced also by quinones (vitamin K1 and K2), provided they are non-polar due to a hydrophobic side-chain. Polar vitamin K3, which possess the same functional group as K1 and K2, does not induce the aggregation. The results confirm a principal role of the hydrophobic interactions as a driving force
for the aggregation of chlorosomal BChls. The chlorosomal quinones play an important role in a redox-dependent excitation
quenching, which may protect the cells against damage under oxygenic conditions. We found that aggregates of BChl c with vitamin K1 and K2 exhibit an excitation quenching as well. The amplitude of the quenching depends on quinone concentration, as determined from
fluorescence measurements. No lipid is necessary to induce the quenching, which therefore originates mainly from interactions
of BChl c with quinones incorporated in the aggregate structure. In contrast, only a weak quenching was observed for dimers of BChl
c in buffer (either with or without vitamin K3) and also for BChl c aggregates prepared with a lipid (lecithin). Thus, the weak quenching seems to be a property of BChl c itself. 相似文献