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771.
Okan Ülgen Rami Shnaiderman Christian Zakian Vasilis Ntziachristos 《Journal of biophotonics》2021,14(7):e202000501
Optical fiber sensors can offer robust and miniaturized detection of wideband ultrasound, yielding high sensitivity and immunity to electromagnetic interference. However, the lack of cost-effective manufacturing methods prevents the disseminated use of these sensors in biomedical applications. In this study, we developed and optimized a simple method to create optical cavities with high-quality mirrors for acoustic sensing based on micro-manipulation of UV-curable optical adhesives and electroless chemical silver deposition. This approach enables the manufacturing of ultrasound sensors based on Fabry-Pérot interferometers on optical fiber tips with minimal production costs. Characterization and high-resolution optoacoustic imaging experiments show that the manufacturing process yielded a fiber sensor with a small NEP () over a broad detection bandwidth (25 MHz), generally outperforming conventional piezoelectric based transducers. We discuss how the new manufacturing process leads to a high-performance acoustic detector that, due to low cost, can be used as a disposable sensor. 相似文献
772.
Manolis Maragkakis Panagiotis Alexiou Tadashi Nakaya Zissimos Mourelatos 《RNA (New York, N.Y.)》2016,22(1):1-9
Immunoprecipitation of RNA binding proteins (RBPs) after in vivo crosslinking, coupled with sequencing of associated RNA footprints (HITS-CLIP, CLIP-seq), is a method of choice for the identification of RNA targets and binding sites for RBPs. Compared with RNA-seq, CLIP-seq analysis is widely diverse and depending on the RBPs that are analyzed, the approaches vary significantly, necessitating the development of flexible and efficient informatics tools. In this study, we present CLIPSeqTools, a novel, highly flexible computational suite that can perform analysis from raw sequencing data with minimal user input. It contains a wide array of tools to provide an in-depth view of CLIP-seq data sets. It supports extensive customization and promotes improvization, a critical virtue, since CLIP-seq analysis is rarely well defined a priori. To highlight CLIPSeqTools capabilities, we used the suite to analyze Ago-miRNA HITS-CLIP data sets that we prepared from human brains. 相似文献
773.
Panagiotis Kornilios Evanthia Thanou Petros Lymberakis Roberto Sindaco Cristiano Liuzzi Sinos Giokas 《Zoologica scripta》2014,43(2):149-160
The four‐lined snake, Elaphe quatuorlineata, has a fragmented distribution, restricted in continental regions and islands of the Italian and Balkan peninsulas, and includes several morphologically described subspecies. In this study, mtDNA sequences are used to investigate its evolutionary and biogeographical history, to explore the role of palaeogeography, palaeoclimate and human activities in shaping the observed phylogeographical patterns and to discuss whether current subspecific taxonomy is consistent with the intraspecific phylogeny. The phylogeography of the species is a result of both vicariant and dispersal events, some of them transmarine and even human mediated. Its diversification began approximately 3.5 Mya and continued during the Pleistocene glacial periods, when the four‐lined snake's range was restricted in the Italian and Balkan peninsulas, and subsequently expanded from subrefugia, which acted as ‘biodiversity pockets’. Our study supports the recognition of three genetic lineages that roughly correspond to the morphological subspecies, although the morphological characters used for their discrimination should be re‐evaluated. It seems that the current morphological subspecies correspond to ecomorphs associated with body size change in island snakes and the island‐dwarfism phenomenon. 相似文献
774.
Theodora Manolakou Valeria Kaltezioti Niki Prakoura Panagiotis Kavvadas Simone Reichelt-Wurm Harikleia Gakiopoulou Miriam Banas Bernhard Banas Maja T. Lindenmeyer Clemens D. Cohen Peter Boor Sonja Djudjaj Dimitrios T. Boumpas Christos Chatziantoniou Aristidis Charonis Panagiotis K. Politis 《Journal of cellular and molecular medicine》2023,27(9):1192-1205
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Multiple reversals of chirality in the land snail genus Albinaria (Gastropoda,Clausiliidae)
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Reversed chirality has frequently evolved in snails, although the vast majority coils dextrally. However, there are often sinistral species within a dextral genus or almost exclusively sinistral families, such as the Clausiliidae. Some populations of the predominantly sinistral clausiliid genus Albinaria, in the southern Greek mainland, coil dextrally. The origin, evolution and distribution of the dextral Albinaria are puzzling, and as there is no reliable phylogenetic reconstruction for this speciose genus, it remains unclear how many times a shift in chirality has really occurred. In this study, our aim was to elucidate the evolutionary pathways of dextrality in Albinaria. We undertook a molecular phylogenetic analysis of two mtDNA (16S and COI) and one nDNA marker (ITS1) and included dextral and sinistral representatives found in syntopy or not. Both mtDNA and nDNA tree topologies imply that dextrals did not evolve as a monophyletic lineage. Instead, dextral lineages have evolved from sinistral ancestors multiple times independently. The fragmented population structure in Albinaria facilitates genetic drift and contributes to fixation of the opposite chirality and overcoming of the mating disadvantage of left–right reversal. Stochastic phenomena and biogeographical barriers have trapped those reversals in a limited geographical area. 相似文献
778.
Georgios Renieris Dionysia-Eirini Droggiti Konstantina Katrini Panagiotis Koufargyris Theologia Gkavogianni Eleni Karakike Nikolaos Antonakos Georgia Damoraki Athanasios Karageorgos Labros Sabracos Antonia Katsouda Elisa Jentho Sebastian Weis Rui Wang Michael Bauer Csaba Szabo Kalliopi Platoni Vasilios Kouloulias Andreas Papapetropoulos Evangelos J. Giamarellos-Bourboulis 《PLoS pathogens》2021,17(3)
Hydrogen sulfide (H2S) has recently been recognized as a novel gaseous transmitter with several anti-inflammatory properties. The role of host- derived H2S in infections by Pseudomonas aeruginosa was investigated in clinical and mouse models. H2S concentrations and survival was assessed in septic patients with lung infection. Animal experiments using a model of severe systemic multidrug-resistant P. aeruginosa infection were performed using mice with a constitutive knock-out of cystathionine-γ lyase (Cse) gene (Cse-/-) and wild-type mice with a physiological expression (Cse+/+). Experiments were repeated in mice after a) treatment with cyclophosphamide; b) bone marrow transplantation (BMT) from a Cse+/+ donor; c) treatment with H2S synthesis inhibitor aminooxyacetic acid (ΑΟΑΑ) or propargylglycine (PAG) and d) H2S donor sodium thiosulfate (STS) or GYY3147. Bacterial loads and myeloperoxidase activity were measured in tissue samples. The expression of quorum sensing genes (QS) was determined in vivo and in vitro. Cytokine concentration was measured in serum and incubated splenocytes. Patients survivors at day 28 had significantly higher serum H2S compared to non-survivors. A cut- off point of 5.3 μΜ discriminated survivors with sensitivity 92.3%. Mortality after 28 days was 30.9% and 93.7% in patients with H2S higher and less than 5.3 μΜ (p = 7 x 10−6). In mice expression of Cse and application of STS afforded protection against infection with multidrug-resistant P. aeruginosa. Cyclophosphamide pretreatment eliminated the survival benefit of Cse+/+ mice, whereas BMT increased the survival of Cse-/- mice. Cse-/- mice had increased pathogen loads compared to Cse+/+ mice. Phagocytic activity of leukocytes from Cse-/- mice was reduced but was restored after H2S supplementation. An H2S dependent down- regulation of quorum sensing genes of P.aeruginosa could be demonstrated in vivo and in vitro. Endogenous H2S is a potential independent parameter correlating with the outcome of P. aeruginosa. H2S provides resistance to infection by MDR bacterial pathogens. 相似文献
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780.
Panagiotis Stathopoulos Serafim Papas Vassilios Tsikaris 《Journal of peptide science》2006,12(3):227-232
Decomposition of the resin linkers during TFA cleavage of the peptides in the Fmoc strategy leads to alkylation of sensitive amino acids. The C-terminal amide alkylation, reported for the first time, is shown to be a major problem in peptide amides synthesized on the Rink amide resin. This side reaction occurs as a result of the Rink amide linker decomposition under TFA treatment of the peptide resin. The use of 1,3-dimethoxybenzene in a cleavage cocktail prevents almost quantitatively formation of C-terminal N-alkylated peptide amides. Oxidized by-product in the tested Cys- and Met-containing peptides were not observed, even if thiols were not used in the cleavage mixture. 相似文献