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111.
Nakul Mandal Steffen Heegaard Jan Ulrik Prause Bent Honoré Henrik Vorum 《Biological procedures online》2010,12(1):56-88
The intention of this review is to provide an overview of current methodologies employed in the rapidly developing field of
ocular proteomics with emphasis on sample preparation, two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and mass
spectrometry (MS). Appropriate sample preparation for the diverse range of cells and tissues of the eye is essential to ensure
reliable results. Current methods of protein staining for 2D-PAGE, protein labelling for two-dimensional difference gel electrophoresis,
gel-based expression analysis and protein identification by MS are summarised. The uses of gel-free MS-based strategies (MuDPIT,
iTRAQ, ICAT and SILAC) are also discussed. Proteomic technologies promise to shed new light onto ocular disease processes
that could lead to the discovery of strong novel biomarkers and therapeutic targets useful in many ophthalmic conditions. 相似文献
112.
Pollinator population size and pollination ecosystem service responses to enhancing floral and nesting resources 下载免费PDF全文
Johanna Häussler Ullrika Sahlin Charlotte Baey Henrik G. Smith Yann Clough 《Ecology and evolution》2017,7(6):1898-1908
Modeling pollination ecosystem services requires a spatially explicit, process‐based approach because they depend on both the behavioral responses of pollinators to the amount and spatial arrangement of habitat and on the within‐ and between‐season dynamics of pollinator populations in response to land use. We describe a novel pollinator model predicting flower visitation rates by wild central‐place foragers (e.g., nesting bees) in spatially explicit landscapes. The model goes beyond existing approaches by: (1) integrating preferential use of more rewarding floral and nesting resources; (2) considering population growth over time; (3) allowing different dispersal distances for workers and reproductives; (4) providing visitation rates for use in crop pollination models. We use the model to estimate the effect of establishing grassy field margins offering nesting resources and a low quantity of flower resources, and/or late‐flowering flower strips offering no nesting resources but abundant flowers, on bumble bee populations and visitation rates to flowers in landscapes that differ in amounts of linear seminatural habitats and early mass‐flowering crops. Flower strips were three times more effective in increasing pollinator populations and visitation rates than field margins, and this effect increased over time. Late‐blooming flower strips increased early‐season visitation rates, but decreased visitation rates in other late‐season flowers. Increases in population size over time in response to flower strips and amounts of linear seminatural habitats reduced this apparent competition for pollinators. Our spatially explicit, process‐based model generates emergent patterns reflecting empirical observations, such that adding flower resources may have contrasting short‐ and long‐term effects due to apparent competition for pollinators and pollinator population size increase. It allows exploring these effects and comparing effect sizes in ways not possible with other existing models. Future applications include species comparisons, analysis of the sensitivity of predictions to life‐history traits, as well as large‐scale management intervention and policy assessment. 相似文献
113.
Gnetalean compression-impression fossils are described from the Early Cretaceous Yixian Formation, Liaoning Province, north-eastern
China, and assigned to six species of Liaoxia Cao et S.Q. Wu. The fossils have opposite-decussate phyllotaxis and cones comprising 2–12 pairs of bracts. Ovulate cones
have seeds typically in a distal position. The species differ from each other and from previously described fossils in the
absence or presence of leaves, shape of cones and seeds, and shape and position of cone bracts. The species of Liaoxia are probably close relatives of extant species of Ephedra L., but diagnostic reproductive details that could confirm this hypothesis are not preserved. The restricted information
in the fossils and the poorly understood morphological diversity of extant Ephedra, prevent assignment of the fossils to any particular subgroup of Ephedra, as well as an explicit exclusion of them from the extant genus. 相似文献
114.
Søndergaard H Frederiksen KS Thygesen P Galsgaard ED Skak K Kristjansen PE Odum N Kragh M 《Cancer immunology, immunotherapy : CII》2007,56(9):1417-1428
Interleukin (IL)-21 is a recently discovered cytokine in early clinical development, which has shown anti-tumor activity in
various animal models. In the present study, we examine the anti-tumor activity of IL-21 protein therapy in two syngeneic
tumor models and its effect on the density of tumor infiltrating T cells. We treated mice bearing established subcutaneous
B16 melanomas or RenCa renal cell carcinomas with intraperitoneal (i.p.) or subcutaneous (s.c.) IL-21 protein therapy and
subsequently scored the densities of tumor infiltrating CD4+ and CD8+ T cells by immunohistochemistry. Whereas both routes of IL-21 administration significantly inhibited growth of small, established
RenCa and B16 tumors, only s.c. therapy significantly inhibited the growth of large, established tumors. We found a greater
bioavailability and significant drainage of IL-21 to regional lymph nodes following s.c. administration, which could account
for the apparent increase in anti-tumor activity. Specific depletion of CD8+ T cells with monoclonal antibodies completely abrogated the anti-tumor activity, whereas NK1.1+ cell depletion did not affect tumor growth. In accordance, both routes of IL-21 administration significantly increased the
density of tumor infiltrating CD8+ T cells in both B16 and RenCa tumors; and in the RenCa model s.c. administration of IL-21 led to a significantly higher density
of tumor infiltrating CD8+ T cells compared to i.p. administration. The densities of CD4+ T cells were unchanged following IL-21 treatments. Taken together, these data demonstrate that IL-21 protein has anti-tumor
activity in established syngeneic tumors, and we show that IL-21 therapy markedly increases the density of tumor infiltrating
CD8+ T cells. 相似文献
115.
The Hardangervidda in southern Norway, the largest mountain plateau in Europe, has thousands of lakes and streams, mainly
between 1000 and 1300 m above sea level, where brown trout is the only fish species. To describe the current genetic diversity
of brown trout in this area, a total of 863 fish from 20 lakes were genotyped with eleven microsatellites. Most diversity
is within lake populations, but diversity among geographical groups and populations within groups was significant, too. Neighbor-joining,
principle coordinate analysis and Bayesian clustering show three major geographic groups in accordance with the river systems.
Bias was caused by recent stocking in two lakes. Low/no genetic differentiation among some populations indicates that intermixing
is common when lakes are well-connected, as was also shown by assignment test. We recommend preserving the genetic diversity
of brown trout in this unique area by managing stocking in lake systems according to genetic structure. 相似文献
116.
Twenty Aspergillus strains were evaluated for production of extracellular cellulolytic and xylanolytic activities. Aspergillus brasiliensis, A. niger and A. japonicus produced the highest xylanase activities with the A. brasiliensis and A. niger strains producing thermostable β-xylosidases. The β-xylosidase activities of the A. brasiliensis and A. niger strains had similar temperature and pH optima at 75°C and pH 5 and retained 62% and 99%, respectively, of these activities
over 1 h at 60°C. At 75°C, these values were 38 and 44%, respectively. Whereas A. niger is a well known enzyme producer, this is the first report of xylanase and thermostable β-xylosidase production from the newly
identified, non-ochratoxin-producing species A. brasiliensis. 相似文献
117.
118.
Per-Henrik D Edqvist Madelen Lek Henrik Boije Sarah M Lindbäck Finn Hallböök 《BMC developmental biology》2008,8(1):46
Background
Horizontal cells are retinal interneurons that modulate the output from photoreceptors. A rich literature on the morphological classification and functional properties of HCs in different animals exists, however, the understanding of the events underlying their development is still limited. In most vertebrates including chicken, two main horizontal cell (HC) subtypes are identified based on the presence or absence of an axon. 相似文献119.
Amyotrophic lateral sclerosis (ALS) is a progressive motor neuron disease with largely unknown pathogenesis that typically results in death within a few years from diagnosis. There are currently no effective therapies for ALS. Clinical diagnosis usually takes several months to complete and the long delay between symptom onset and diagnosis limits the possibilities for effective intervention and clinical trials. The establishment of protein biomarkers for ALS may aid an earlier diagnosis, facilitating the search for effective therapeutic interventions and monitoring drug efficacy during clinical trials. Biomarkers could also be used to discriminate between subtypes of ALS, to measure disease progression and to detect susceptibility for developing ALS or monitor adverse effects of drug treatment. The present review will discuss the opportunities and proteomic platforms used for biomarker discovery efforts in ALS, summarizing putative ALS protein biomarkers identified in different biofluids. 相似文献
120.
Helle Wulf-Johansson Sofie Lock Johansson Anders Schlosser Anne Trommelholt Holm Lars Melholt Rasmussen Hans Mickley Axel C. P. Diederichsen Henrik Munkholm Tina Svenstrup Poulsen Ida Torn?e Vicki Nielsen Niels Marcussen J?rgen Vestbo Susanne Gj?rup S?kmose Uffe Holmskov Grith Lykke Sorensen 《PloS one》2013,8(12)
Microfibrillar-associated protein 4 (MFAP4) is located in the extracellular matrix (ECM). We sought to identify tissues with high levels of MFAP4 mRNA and MFAP4 protein expression. Moreover, we aimed to evaluate the significance of MFAP4 as a marker of cardiovascular disease (CVD) and to correlate MFAP4 with other known ECM markers, such as fibulin-1, osteoprotegerin (OPG), and osteopontin (OPN). Quantitative real-time PCR demonstrated that MFAP4 mRNA was more highly expressed in the heart, lung, and intestine than in other elastic tissues. Immunohistochemical studies demonstrated high levels of MFAP4 protein mainly at sites rich in elastic fibers and within blood vessels in all tissues investigated. The AlphaLISA technique was used to determine serum MFAP4 levels in a clinical cohort of 172 patients consisting of 5 matched groups with varying degrees of CVD: 1: patients with ST elevation myocardial infarction (STEMI), 2: patients with non-STEMI, 3: patients destined for vascular surgery because of various atherosclerotic diseases (stable atherosclerotic disease), 4: apparently healthy individuals with documented coronary artery calcification (CAC-positive), and 5: apparently healthy individuals without signs of coronary artery calcification (CAC-negative). Serum MFAP4 levels were significantly lower in patients with stable atherosclerotic disease than CAC-negative individuals (p<0.05). Furthermore, lower serum MFAP4 levels were present in patients with stable atherosclerotic disease compared with STEMI and non-STEMI patients (p<0.05). In patients with stable atherosclerotic disease, positive correlations between MFAP4 and both fibulin-1 (ρ = 0.50; p = 0.0244) and OPG (ρ = 0.62; p = 0.0014) were found. Together, these results indicate that MFAP4 is mainly located in elastic fibers and is highly expressed in blood vessels. The present study suggests that serum MFAP4 varies in groups of patients with different cardiovascular conditions. Further studies are warranted to describe the role of serum MFAP4 as a biomarker of stable atherosclerotic disease. 相似文献