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Elena Alexopoulou Aristidis Georgopoulos Konstantinos A. Kagkadis Costas Demetzos 《Journal of liposome research》2013,23(1):17-25
Liposomes composed of egg-phosphatidylcholine (EPC) incorporating quercetin (QR) were prepared by the thin-film hydration method (TFHM) and the monophase solution method (MSM). A rapid and slow freeze-drying process was applied for both laboratory and industrial scales. The purpose of this study was to compare the two methods of liposome preparation, and further determine whether the lyophilization process affects the liposome physicochemical characteristics (size, polydispersity index, and ζ-potential) and incorporation of quercetin. 相似文献
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Cardamine calliphaea Kit Tan, G. Vold & Giannopoulos sp. nov. (Brassicaceae) is illustrated and described as a new species endemic to Greece. It occurs in the prefectures of Ilia in western Peloponnese and Etolias‐Akarnanias in western Sterea Ellas and bears some resemblance to C. graeca, differing by its dense greyish–white indumentum and by the absence of leaf auricles. Affinities lie with C. glauca and C. plumieri from which it differs conspicuously, among other characters, by its imparipinnate leaves with the terminal leaflet smaller or equal in size to the lateral pairs. 相似文献
45.
Wei-Chien Hung Shih-Hsun Chen Colin D. Paul Kimberly M. Stroka Ying-Chun Lo Joy T. Yang Konstantinos Konstantopoulos 《The Journal of cell biology》2013,202(5):807-824
Using a microchannel assay, we demonstrate that cells adopt distinct signaling strategies to modulate cell migration in different physical microenvironments. We studied α4β1 integrin–mediated signaling, which regulates cell migration pertinent to embryonic development, leukocyte trafficking, and melanoma invasion. We show that α4β1 integrin promotes cell migration through both unconfined and confined spaces. However, unlike unconfined (2D) migration, which depends on enhanced Rac1 activity achieved by preventing α4/paxillin binding, confined migration requires myosin II–driven contractility, which is increased when Rac1 is inhibited by α4/paxillin binding. This Rac1–myosin II cross talk mechanism also controls migration of fibroblast-like cells lacking α4β1 integrin, in which Rac1 and myosin II modulate unconfined and confined migration, respectively. We further demonstrate the distinct roles of myosin II isoforms, MIIA and MIIB, which are primarily required for confined and unconfined migration, respectively. This work provides a paradigm for the plasticity of cells migrating through different physical microenvironments. 相似文献
46.
Konstantinos Feidantsis Efthimia Antonopoulou Antigone Lazou Hans O. Pörtner Basile Michaelidis 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2013,183(5):625-639
The present study aimed to investigate the seasonal cellular stress response in vital organs, like the heart, the liver, the whole blood and the skeletal (red and white) muscles of the Mediterranean fish Sparus aurata during a 1-year acclimatization period in the field, in two examined depths (0–2 m and 10–12 m). Processes studied included heat shock protein expression and protein kinase activation. Molecular responses were addressed through the expression of Hsp70 and Hsp90, the phosphorylation of stress-activated protein kinases and particularly p38 mitogen-activated protein kinase (p38 MAPK), the extracellular signal-regulated kinases (ERK-1/2) and c-Jun N-terminal kinases (JNK1/2/3). The induction of Hsp70 and Hsp90 and the phosphorylation of p38 MAPK, JNKs and ERKs in the examined five tissues of the gilthead sea bream indicated a cellular stress response under the prism of a seasonal pattern which was characterized by distinct tissue specificity. Specifically, Hsp induction and MAPK activation occurred before peak summer water temperatures, with no further increases in their levels despite increases in water temperatures. Moreover, although water temperature did not vary significantly with depth of immersion, significant effects of depth on cellular stress response were observed, probably caused by different light regime. The expression and the activation of these certain proteins can be used as tools to define the extreme thermal limits of the gilthead sea bream. 相似文献
47.
Penelope Bouziotis Eleni Gourni George Patsis Dimitrios Psimadas Christos Zikos Melpomeni Fani Stavros Xanthopoulos George Loudos Maria Paravatou-Petsotas Evangelia Livaniou Alexandra D. Varvarigou Ioannis Pirmettis Minas Papadopoulos 《Bioorganic & medicinal chemistry》2013,21(21):6699-6707
Bombesin is a neuropeptide widely studied due to its ability to target various types of cancers. Technetium-99m on the other hand is ideal for diagnostic tumor targeting. The aim of the present study is the investigation of the coupling of the ligand (S)-(2-(2′-pyridyl)ethyl)-d,l-cysteine with the BN-peptide Gln-Arg-Leu-Gly-Asn-Gln-Trp-Ala-Val-Gly-His-Leu-Met(CONH2) through the spacer aminohexanoic acidand the labeling of the resulting derivative MBN with the synthon [M(CO)3(H2O)3]+ (M = 99mTc, Re). The peptide was synthesized according to the SPPS method, purified and characterized by ESI-MS. The new 99mTc-labeled biomolecule was stable in vitro, showed high affinity for the human GRP receptor expressed in PC3 cells and the rate of internalization was found to be time-dependent tissue distribution of the radiopeptide was evaluated in normal mice and in prostate cancer experimental models and significant radioactivity uptake was observed in the pancreas of normal mice as well as in PC3 tumors. Dynamic studies of the radiopeptide showed satisfactory tumor images. 相似文献
48.
Stelios Paraskevaidis Efstratios K. Theofilogiannakos Vasileios Kamperidis Yiannis S. Chatzizisis Konstantinos Tsilonis Vassilios P. Vassilikos George Dakos George Stavropoulos Antonios Ziakas Stavros Hadjimiltiades Ioannis H. Styliadis 《Indian pacing and electrophysiology journal》2013,13(5):178-180
Brugada syndrome is an inherited channelopathy associated with an increased risk of syncope and sudden cardiac death. In rare cases it can be manifested with electrical storm. We report two cases of Brugada syndrome that presented with electrical storm and were treated successfully with oral quinidine, an "endangered species" drug. 相似文献
49.
Marta Corton Koji M. Nishiguchi Almudena Avila-Fernández Konstantinos Nikopoulos Rosa Riveiro-Alvarez Sorina D. Tatu Carmen Ayuso Carlo Rivolta 《PloS one》2013,8(6)
Background
Retinal dystrophies (RD) are a group of hereditary diseases that lead to debilitating visual impairment and are usually transmitted as a Mendelian trait. Pathogenic mutations can occur in any of the 100 or more disease genes identified so far, making molecular diagnosis a rather laborious process. In this work we explored the use of whole exome sequencing (WES) as a tool for identification of RD mutations, with the aim of assessing its applicability in a diagnostic context.Methodology/Principal Findings
We ascertained 12 Spanish families with seemingly recessive RD. All of the index patients underwent mutational pre-screening by chip-based sequence hybridization and resulted to be negative for known RD mutations. With the exception of one pedigree, to simulate a standard diagnostic scenario we processed by WES only the DNA from the index patient of each family, followed by in silico data analysis. We successfully identified causative mutations in patients from 10 different families, which were later verified by Sanger sequencing and co-segregation analyses. Specifically, we detected pathogenic DNA variants (∼50% novel mutations) in the genes RP1, USH2A, CNGB3, NMNAT1, CHM, and ABCA4, responsible for retinitis pigmentosa, Usher syndrome, achromatopsia, Leber congenital amaurosis, choroideremia, or recessive Stargardt/cone-rod dystrophy cases.Conclusions/Significance
Despite the absence of genetic information from other family members that could help excluding nonpathogenic DNA variants, we could detect causative mutations in a variety of genes known to represent a wide spectrum of clinical phenotypes in 83% of the patients analyzed. Considering the constant drop in costs for human exome sequencing and the relative simplicity of the analyses made, this technique could represent a valuable tool for molecular diagnostics or genetic research, even in cases for which no genotypes from family members are available. 相似文献50.
Network connections have been shown to be correlated with structural or external attributes of the network vertices in a variety of cases. Given the prevalence of this phenomenon network scientists have developed metrics to quantify its extent. In particular, the assortativity coefficient is used to capture the level of correlation between a single-dimensional attribute (categorical or scalar) of the network nodes and the observed connections, i.e., the edges. Nevertheless, in many cases a multi-dimensional, i.e., vector feature of the nodes is of interest. Similar attributes can describe complex behavioral patterns (e.g., mobility) of the network entities. To date little attention has been given to this setting and there has not been a general and formal treatment of this problem. In this study we develop a metric, the vector assortativity index (VA-index for short), based on network randomization and (empirical) statistical hypothesis testing that is able to quantify the assortativity patterns of a network with respect to a vector attribute. Our extensive experimental results on synthetic network data show that the VA-index outperforms a baseline extension of the assortativity coefficient, which has been used in the literature to cope with similar cases. Furthermore, the VA-index can be calibrated (in terms of parameters) fairly easy, while its benefits increase with the (co-)variance of the vector elements, where the baseline systematically over(under)estimate the true mixing patterns of the network. 相似文献