8 results match your criteria: "1 Institute of Biophysics[Affiliation]"

In recent years, several computer-aided diagnosis systems emerged for the diagnosis of thyroid gland disorders using ultrasound imaging. These systems based on machine learning algorithms may offer a second opinion to radiologists by evaluating a malignancy risk of thyroid tissue, thus increasing the overall diagnostic accuracy of ultrasound imaging. Although current computer-aided diagnosis systems exhibit promising results, their use in clinical practice is limited.

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Despite the potential obstacle represented by the blood-brain barrier for extravasating malignant cells, metastases are more frequent than primary tumors in the central nervous system. Not only tightly interconnected endothelial cells can hinder metastasis formation, other cells of the brain microenvironment (like astrocytes and microglia) can also be very hostile, destroying the large majority of metastatic cells. However, malignant cells that are able to overcome these harmful mechanisms may benefit from the shielding and even support provided by cerebral endothelial cells, astrocytes and microglia, rendering the brain a sanctuary site against anti-tumor strategies.

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Electrotonic potentials allow the accommodative processes to long-lasting subthreshold polarizing stimuli to be assessed. The present study investigates such potentials in previously simulated cases of amyotrophic lateral sclerosis, termed as ALS1, ALS2 and ALS3, respectively, when the temperature is changed during hypothermia ([Formula: see text]C) and hyperthermia ([Formula: see text]C). The ALS cases are modeled as three progressively severe uniform axonal dysfunctions along the human motor nerve fiber which is simulated by our temperature-dependent multi-layered numerical model.

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The present study investigates action potential abnormalities in previously simulated cases of amyotrophic lateral sclerosis, termed as ALS1, ALS2 and ALS3, respectively, when the temperature is changed from 20[Formula: see text]C to 42[Formula: see text]C. These ALS cases are modeled as three progressively severe axonal abnormalities. The effects of temperature on the kinetics of currents, defining action potentials in the normal and abnormal cases, are also given and discussed.

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How water molecules affect the catalytic activity of hydrolases--a XANES study of the local structures of peptide deformylase.

Sci Rep

December 2014

1] National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, China [2] Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China.

Peptide deformylase (PDF) is a prokaryotic enzyme that catalyzes the deformylation of nascent peptides generated during protein synthesis and water molecules play a key role in these hydrolases. Using X-ray absorption near edge spectroscopy (XANES) and ab initio calculations we accurately probe the local atomic environment of the metal ion binding in the active site of PDF at different pH values and with different metal ions. This new approach is an effective way to monitor existing correlations among functions and structural changes.

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The soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) proteins are small and abundant membrane-bound proteins, whose specific interactions mediate membrane fusion during cell fusion or cellular trafficking. In this study, we report the use of a label-free method, called imaging ellipsometer to analyze the interactions among three SNAREs, namely Sec22p, Ykt6p and Sso2p. The SNAREs were immobilized on the silicon wafer and then analyzed in a pairwise mode with microfluidic array, leading us to discover the interactions between Ykt6p and Sso2p, Sec22p and Sso2p.

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Direct recordings of electron currents mediated by cytochromes b561 (CYB561) are not available yet, despite the importance of these proteins in a variety of physiological functions, including neurotransmitter synthesis and dietary iron uptake. Here, we used the two-electrode voltage-clamp technique applied to Xenopus oocytes to demonstrate, for the first time, the generation of electron currents by a Drosophila member of the CYB561 superfamily named stromal cell-derived receptor 2 (SDR2). This experimental method, along with the theoretical development of a three-state kinetic model, supports the hypothesis that electron donor/acceptor concentrations and transmembrane voltage mutually control SDR2-mediated electron transport activity in a complex but predictable manner.

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The MST/YAP (mammalian Ste20-like kinase/Yes-associated protein 2) pathway plays an important role in hepatocellular carcinoma (HCC). Although post-translational modification-especially MST/Lats (large tumor suppressor)-mediated phosphorylation and PP1 (protein phosphatase-1)-mediated dephosphorylation-has been found to regulate the activity of YAP2, very little is known about its acetylation. In our experiments, we observed that the expression of SIRT1 is significantly upregulated in the tumor samples of the hepatocarcinoma patients, and SIRT1 mRNA level positively correlates with connective tissue growth factor (CTGF) mRNA level.

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