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991.
Marko Lukić Teo Delić Martina Pavlek Louis Deharveng Maja Zagmajster 《Zoologica scripta》2020,49(1):86-100
One of the most striking features of obligate subterranean species is their narrow distribution ranges. These prevail not only at specific, but often also at generic level. However, some subterranean genera have continental scale and disjunct distribution, which challenges their monophyly and questions the scenarios of their origin and colonization. In our study, we investigated the subterranean collembolan genus Verhoeffiella, currently known from five remote karst regions of Europe. Four nuclear and one mitochondrial genes were assembled to reveal the evolutionary history of the genus. We tested the monophyly of the genus, explored its relationship with putative surface relatives, and its temporal patterns of molecular diversification. The phylogeny revealed a complex relationship of Verhoeffiella with surface species Heteromurus nitidus and partially disentangled the biogeographical question of its disjunct distribution. Further on, several lineages of Verhoeffiella were recognized in the Dinarides, showing highly underestimated diversity and, compared with the number of described species, a sevenfold increase in the number of MOTUs. The radiation is relatively recent, with the events triggering the diversification linked to the Messinian salinity crisis and Pleistocene climatic shifts. The combination of this extensive subterranean radiation and close evolutionary links with epigean relatives makes Verhoeffiella an exceptional case within the subterranean fauna of temperate areas, which significantly contributes to our understanding of subterranean colonization and diversification patterns. 相似文献
992.
Nataša Obermajer Urban Švajger Sara Sattin Marko Anderluh 《Analytical biochemistry》2010,406(2):222-229
We report a new dendritic cell adhesion assay, using either immature or mature dendritic cells, for identifying functional dendritic cell-specific ICAM-3-grabbing nonintegrin (DC-SIGN) inhibitors. Because immature dendritic cells are responsible for pathogen binding and invasion, this in vitro assay provides an important link between in vitro results and pathogen-based in vivo assays. Furthermore, this assay does not require laborious expression, refolding, and purification of DC-SIGN carbohydrate recognition domain or extracellular domain as receptor-based assays. The assay power evaluated with Z and Z′ parameters enables screening of compound libraries and determination of IC50 values in the first stage of DC-SIGN inhibitor development. 相似文献
993.
Beside olfactory or trigeminal stimulation of chemosensory receptor-cellssome results in published literature suggest that fragrancesshow a direct affect on the brain. The effect of the fragrance1,8-cineol, which was described in literature as stimulating,on regional and global cerebral blood flow (rCBF and gCBF) inthe human brain after prolonged inhalation was investigated.The results show an increase of global-CBF without preferenceto primary or secondary olfactory centres after an inhalation-timeof 20 min. 相似文献
994.
Isidora Stojic Ivan Srejovic Vladimir Zivkovic Nevena Jeremic Marko Djuric Ana Stevanovic Tamara Milanovic Dragan Djuric Vladimir Jakovljevic 《Journal of physiology and biochemistry》2017,73(1):141-153
The role of N-methyl-D-aspartate receptor (NMDA-R) in heart is still unclear. For these ionotropic glutamate receptors is characteristic the necessity of both co-agonists, glutamate and glycine, for their activation, which primarily allows influx of calcium. The aim of the present study was to examine the effects of verapamil, as a calcium channel blocker, alone and its combination with glycine and/or glutamate on cardiac function, coronary flow, and oxidative stress in isolated rat heart or to examine the effects of potential activation of NMDA-R in isolated rat heart. The hearts of male Wistar albino rats were excised and perfused according to Langendorff technique, and cardiodynamic parameters and coronary flow were determined during the administration of verapamil and its combinations with glutamate and/or glycine. The oxidative stress biomarkers, including thiobarbituric acid-reactive substances, nitrites, superoxide anion radical, and hydrogen peroxide, were each determined spectrophotometrically from coronary venous effluent. The greatest decline in parameters of cardiac contractility and systolic pressure was in the group that was treated with verapamil only, while minimal changes were observed in group treated with all three tested substances. Also, the largest changes in coronary flow were in the group treated only with verapamil, and at least in the group that received all three tested substances, as well as the largest increase in oxidative stress parameters. Based on the obtained results, it can be concluded that NMDA-R activation allows sufficient influx of calcium to increase myocardial contractility and systolic pressure, as well as short-term increase of oxidative stress. 相似文献
995.
Renata Šoštarić Darko Kovačić Marko Ćaleta Antun Alegro Božena Mitić 《Vegetation History and Archaeobotany》2008,17(3):289-295
Archaeobotanical analysis has been used to reconstruct the nest and diet of a small rodent from the Classical period (first
century b.c. to second century a.d.) and most probably from Greece. The nest was found in the hollow interior of a very valuable bronze statue of a young athlete,
recovered from the waters of the Northern Adriatic and named the Croatian Apoxyomenos. Apoxyomenos was probably the cargo
of a Roman ship on one of highly frequented sea routes in ancient times, along which, among other things, a highly developed
trade in artworks was maintained. All plant remains were non-carbonised and mineralised; encrusted with metallic salts, especially
of copper, and preserved in excellent condition. The nest itself (wisps of “straw” found in the hollow interior of the left
forearm of the statue) was mainly composed of stems and leaves of grasses (Poaceae), but also of laurel (Laurus nobilis) leaves and other plant remains. Along with “straw”, a further 837 individual plant remains were found and analysed and 41
different plant taxa were identified. Plant remains that presumably were part of the rodent’s diet belong to various wild
and cultivated plants which indicate various anthropogenic habitats probably situated somewhere on the edge of human settlement.
From zoological analysis of bite marks found on fruit stones of cherry and olive, and of the potential rodent fauna in the
area the statue was assumed to be in prior to becoming submerged, it was established that the rodent was most probably one
of the taxa of the Mus domesticus group. 相似文献
996.
Simon Ströbel Marko Loparic David Wendt Andreas D Schenk Christian Candrian Raija LP Lindberg Florina Moldovan Andrea Barbero Ivan Martin 《Arthritis research & therapy》2010,12(2):R34
Introduction
Oxygen is a critical parameter proposed to modulate the functions of chondrocytes ex-vivo as well as in damaged joints. This article investigates the effect of low (more physiological) oxygen percentage on the biosynthetic and catabolic activity of human articular chondrocytes (HAC) at different phases of in vitro culture. 相似文献997.
Meaning is a central concept of (bio)semiotics. At the same time, it is also a word of everyday language. Here, on the example of the world information, we discuss the “reduction-inflation model” of evolution of a common word into a scientific concept, to return subsequently into everyday circulation with new connotations. Such may be, in the near future, also the fate of the word meaning if, flexed through objectified semantics, will become considered an objective concept usable in semiotics. We argue that reducing meaning to a technical term essentially synonymous to code and stripped of most of the original semantic field is not a necessary prerequisite for a meaningful application of the concept in semiotics and in biology. 相似文献
998.
Botao Xiao Benjamin S. Freedman Kelly E. Miller Rebecca Heald John F. Marko 《Molecular biology of the cell》2012,23(24):4864-4871
Histone H1 binds to linker DNA between nucleosomes, but the dynamics and biological ramifications of this interaction remain poorly understood. We performed single-molecule experiments using magnetic tweezers to determine the effects of H1 on naked DNA in buffer or during chromatin assembly in Xenopus egg extracts. In buffer, nanomolar concentrations of H1 induce bending and looping of naked DNA at stretching forces below 0.6 pN, effects that can be reversed with 2.7-pN force or in 200 mM monovalent salt concentrations. Consecutive tens-of-nanometer bending events suggest that H1 binds to naked DNA in buffer at high stoichiometries. In egg extracts, single DNA molecules assemble into nucleosomes and undergo rapid compaction. Histone H1 at endogenous physiological concentrations increases the DNA compaction rate during chromatin assembly under 2-pN force and decreases it during disassembly under 5-pN force. In egg cytoplasm, histone H1 protects sperm nuclei undergoing genome-wide decondensation and chromatin assembly from becoming abnormally stretched or fragmented due to astral microtubule pulling forces. These results reveal functional ramifications of H1 binding to DNA at the single-molecule level and suggest an important physiological role for H1 in compacting DNA under force and during chromatin assembly. 相似文献
999.
Cell electrofusion is a safe, non-viral and non-chemical method that can be used for preparing hybrid cells for human therapy. Electrofusion involves application of short high-voltage electric pulses to cells that are in close contact. Application of short, high-voltage electric pulses causes destabilization of cell plasma membranes. Destabilized membranes are more permeable for different molecules and also prone to fusion with any neighboring destabilized membranes. Electrofusion is thus a convenient method to achieve a non-specific fusion of very different cells in vitro. In order to obtain fusion, cell membranes, destabilized by electric field, must be in a close contact to allow merging of their lipid bilayers and consequently their cytoplasm. In this video, we demonstrate efficient electrofusion of cells in vitro by means of modified adherence method. In this method, cells are allowed to attach only slightly to the surface of the well, so that medium can be exchanged and cells still preserve their spherical shape. Fusion visualization is assessed by pre-labeling of the cytoplasm of cells with different fluorescent cell tracker dyes; half of the cells are labeled with orange CMRA and the other half with green CMFDA. Fusion yield is determined as the number of dually fluorescent cells divided with the number of all cells multiplied by two. 相似文献
1000.