2,624 research outputs found
New approach in the treatment of ophthalmic neovascular disorders: using fusion protein aflibercept
The aim of this review is to appraise the usage of a newly approved anti-vascular endothelial growth factor (anti-VEGF) fusion protein, aflibercept, in ocular neovascular disorders such as diabetic retinopathy and age-related macular degeneration. Aflibercept is a soluble fusion protein, which combines ligand-binding elements taken from the extracellular domains of VEGF receptors 1 and 2 fused to the Fc portion of IgG. This protein contains all human amino acid sequences, which minimizes the risk for immunogenicity in human patients. In this short review we investigate the available literature and data from clinical studies on the efficacy, pharmaceutical and pharmacological properties of aflibercept, and identify its possible advantages over commercially available anti-VEGF drugs.Biomedical Reviews 2014; 25: 59-65
A universal form of slow dynamics in zero-temperature random-field Ising model
The zero-temperature Glauber dynamics of the random-field Ising model
describes various ubiquitous phenomena such as avalanches, hysteresis, and
related critical phenomena. Here, for a model on a random graph with a special
initial condition, we derive exactly an evolution equation for an order
parameter. Through a bifurcation analysis of the obtained equation, we reveal a
new class of cooperative slow dynamics with the determination of critical
exponents.Comment: 4 pages, 2 figure
Phase Transition in a Self-repairing Random Network
We consider a network, bonds of which are being sequentially removed; that is
done at random, but conditioned on the system remaining connected
(Self-Repairing Bond Percolation SRBP). This model is the simplest
representative of a class of random systems for which forming of isolated
clusters is forbidden. It qualitatively describes the process of fabrication of
artificial porous materials and degradation of strained polymers. We find a
phase transition at a finite concentration of bonds , at which the
backbone of the system vanishes; for all the network is a dense
fractal.Comment: 4 pages, 4 figure
Optic disc melanocytoma associated with macular cyst
BACKGROUND: Optic disc melanocytoma (ODM) is a benign tumor, most often asymptomatic and stationary. However occasionally it can grow slowly, cause visual loss or extremely rarely undergoes into malignant melanoma. Here lies the importance of periodic ocular examination and reliable documentation.AIM: to report a rare case of growing ODM, associated with macular cyst with related visual loss, 25-years follow-up, and documentation by color photography, optical coherence tomography (OCT) and fluorescein angiography (FAG).METHODS: Full ophthalmic examination, fundus color photography, FAG and OCT.CASE REPORT: An asymptomatic 40-year-old Caucasian female with normal visual acuity at routine ocular examination had a pigmented elevated lesion on the left optic disc, occupying the inferotemporal half. The diagnosis of ODM was based on clinical assessment, FAG, fundus photographies, and observation was recommended. Ten years later she complained of gradually decreasing visual acuity in the left eye. Dilated ophthalmoscopy showed an evidence of slow growth of ODM and initial macular degeneration. After 25 years fundus color photography, FAG, and OCT documented mild progressive growth of ODM and macular cyst in the same eye.CONCLUSION: According to the literature, optic disc melanocytoma is generally recognized to be a stationary lesion with excellent prognosis and no treatment is usually necessary. In our case fundus color photography, FAG and OCT data reveal persisting ODM. Despite the progressive growth of ODM and moderate to significant visual loss, the malignant transformation is not proved. We suggest that loss of vision is related with macular lesion. To our knowledge we report a rare case of 25 years follow-up of growing ODM with visual loss, associated with macula degeneration/cyst.
The topological relationship between the large-scale attributes and local interaction patterns of complex networks
Recent evidence indicates that the abundance of recurring elementary
interaction patterns in complex networks, often called subgraphs or motifs,
carry significant information about their function and overall organization.
Yet, the underlying reasons for the variable quantity of different subgraph
types, their propensity to form clusters, and their relationship with the
networks' global organization remain poorly understood. Here we show that a
network's large-scale topological organization and its local subgraph structure
mutually define and predict each other, as confirmed by direct measurements in
five well studied cellular networks. We also demonstrate the inherent existence
of two distinct classes of subgraphs, and show that, in contrast to the
low-density type II subgraphs, the highly abundant type I subgraphs cannot
exist in isolation but must naturally aggregate into subgraph clusters. The
identified topological framework may have important implications for our
understanding of the origin and function of subgraphs in all complex networks.Comment: pape
Minimum spanning trees on random networks
We show that the geometry of minimum spanning trees (MST) on random graphs is
universal. Due to this geometric universality, we are able to characterise the
energy of MST using a scaling distribution () found using uniform
disorder. We show that the MST energy for other disorder distributions is
simply related to . We discuss the relationship to invasion
percolation (IP), to the directed polymer in a random media (DPRM) and the
implications for the broader issue of universality in disordered systems.Comment: 4 pages, 3 figure
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Inverse Regulation of Inflammation and Mitochondrial Function in Adipose Tissue Defines Extreme Insulin Sensitivity in Morbidly Obese Patients
Obesity is associated with insulin resistance, a major risk factor for type 2 diabetes and cardiovascular disease. However, not all obese individuals are insulin resistant, which confounds our understanding of the mechanistic link between these conditions. We conducted transcriptome analyses on 835 obese subjects with mean BMI of 48.8, on which we have previously reported genetic associations of gene expression. Here, we selected ∼320 nondiabetic (HbA1c <7.0) subjects and further stratified the cohort into insulin-resistant versus insulin-sensitive subgroups based on homeostasis model assessment–insulin resistance. An unsupervised informatics analysis revealed that immune response and inflammation-related genes were significantly downregulated in the omental adipose tissue of obese individuals with extreme insulin sensitivity and, to a much lesser extent, in subcutaneous adipose tissue. In contrast, genes related to β-oxidation and the citric acid cycle were relatively overexpressed in adipose of insulin-sensitive patients. These observations were verified by querying an independent cohort of our published dataset of 37 subjects whose subcutaneous adipose tissue was sampled before and after treatment with thiazolidinediones. Whereas the immune response and inflammation pathway genes were downregulated by thiazolidinedione treatment, β-oxidation and citric acid cycle genes were upregulated. This work highlights the critical role that omental adipose inflammatory pathways might play in the pathophysiology of insulin resistance, independent of body weight
Measurement of an excess in the yield of J/ at very low in Pb-Pb collisions at = 2.76 TeV
We report on the first measurement of an excess in the yield of J/ at
very low transverse momentum ( GeV/) in peripheral hadronic
Pb-Pb collisions at = 2.76 TeV, performed by ALICE at the
CERN LHC. Remarkably, the measured nuclear modification factor of J/ in
the rapidity range reaches about 7 (2) in the range 0-0.3
GeV/ in the 70-90% (50-70%) centrality class. The J/ production cross
section associated with the observed excess is obtained under the hypothesis
that coherent photoproduction of J/ is the underlying physics mechanism.
If confirmed, the observation of J/ coherent photoproduction in Pb-Pb
collisions at impact parameters smaller than twice the nuclear radius opens new
theoretical and experimental challenges and opportunities. In particular,
coherent photoproduction accompanying hadronic collisions may provide insight
into the dynamics of photoproduction and nuclear reactions, as well as become a
novel probe of the Quark-Gluon Plasma.Comment: 18 pages, 3 captioned figures, 1 table, authors from page 13,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/191
Coarse-Graining and Self-Dissimilarity of Complex Networks
Can complex engineered and biological networks be coarse-grained into smaller
and more understandable versions in which each node represents an entire
pattern in the original network? To address this, we define coarse-graining
units (CGU) as connectivity patterns which can serve as the nodes of a
coarse-grained network, and present algorithms to detect them. We use this
approach to systematically reverse-engineer electronic circuits, forming
understandable high-level maps from incomprehensible transistor wiring: first,
a coarse-grained version in which each node is a gate made of several
transistors is established. Then, the coarse-grained network is itself
coarse-grained, resulting in a high-level blueprint in which each node is a
circuit-module made of multiple gates. We apply our approach also to a
mammalian protein-signaling network, to find a simplified coarse-grained
network with three main signaling channels that correspond to cross-interacting
MAP-kinase cascades. We find that both biological and electronic networks are
'self-dissimilar', with different network motifs found at each level. The
present approach can be used to simplify a wide variety of directed and
nondirected, natural and designed networks.Comment: 11 pages, 11 figure
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