- MeSH
- Dacryocystorhinostomy methods MeSH
- Humans MeSH
- Lacrimal Apparatus surgery MeSH
- Imaging, Three-Dimensional utilization MeSH
- Check Tag
- Humans MeSH
- Publication type
- Book Review MeSH
The enzyme UDP-N-acetylglucosamine: α-d-mannoside β-1-6 N-acetylglucosaminyltransferase V (GnT-V) catalyzes the transfer of GlcNAc from the UDP-GlcNAc donor to the α-1-6-linked mannose of the trimannosyl core structure of glycoproteins to produce the β-1-6-linked branching of N-linked oligosaccharides. β-1-6-GlcNAc-branched N-glycans are associated with cancer growth and metastasis. Therefore, the inhibition of GnT-V represents a key target for anti-cancer drug development. However, the development of potent and specific inhibitors of GnT-V is hampered by the lack of information on the three-dimensional structure of the enzyme and on the binding characteristics of its substrates. Here we present the first 3D structure of GnT-V as a result of homology modeling. Various alignment methods, docking the donor and acceptor substrates, and molecular dynamics simulation were used to construct seven homology models of GnT-V and characterize the binding of its substrates. The best homology model is consistent with available experimental data. The three-dimensional model, the structure of the enzyme catalytic site and binding information obtained for the donor and acceptor can be useful in studies of the catalytic mechanism and design of inhibitors of GnT-V.
- MeSH
- Glycosyltransferases chemistry MeSH
- Humans MeSH
- Mannose chemistry MeSH
- Molecular Conformation * MeSH
- Models, Molecular MeSH
- N-Acetylglucosaminyltransferases chemistry MeSH
- Polysaccharides chemistry genetics MeSH
- Molecular Dynamics Simulation MeSH
- Substrate Specificity MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Tooth development has attracted the attention of researchers since the 19th century. It became obvious even then that morphogenesis could not fully be appreciated from two-dimensional histological sections. Therefore, methods of three-dimensional (3D) reconstructions were employed to visualize the surface morphology of developing structures and to help appreciate the complexity of early tooth morphogenesis. The present review surveys the data provided by computer-aided 3D analyses to update classical knowledge of early odontogenesis in the laboratory mouse and in humans. 3D reconstructions have demonstrated that odontogenesis in the early stages is a complex process which also includes the development of rudimentary odontogenic structures with different fates. Their developmental, evolutionary, and pathological aspects are discussed. The combination of in situ hybridization and 3D reconstruction have demonstrated the temporo-spatial dynamics of the signalling centres that reflect transient existence of rudimentary tooth primordia at loci where teeth were present in ancestors. The rudiments can rescue their suppressed development and revitalize, and then their subsequent autonomous development can give rise to oral pathologies. This shows that tooth-forming potential in mammals can be greater than that observed from their functional dentitions. From this perspective, the mouse rudimentary tooth primordia represent a natural model to test possibilities of tooth regeneration.
- MeSH
- Biological Evolution MeSH
- Dentition MeSH
- Diastema embryology MeSH
- In Situ Hybridization methods MeSH
- Humans MeSH
- Mice MeSH
- Odontogenesis * genetics physiology MeSH
- Image Processing, Computer-Assisted MeSH
- Regeneration MeSH
- Imaging, Three-Dimensional methods MeSH
- Tooth, Supernumerary embryology MeSH
- Tooth embryology physiology MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Review MeSH
Echokardiografie je rutinně používanou metodou také v diagnostice nitrosrdečních útvarů. Dvourozměrné zobrazení rychle se pohybujících patologických struktur uvnitř srdečních oddílů přináší řadu specifických problémů a limitací. Jejich ne vždy ideální zobrazení při standardním ultrazvukovém vyšetřování doposud představuje určitou výzvu, neboť chybný závěr a nesprávná diagnóza mohou mít pro osud nemocného vážné důsledky. Podle teoretických předpokladů by trojrozměrná echokardiografie v reálném čase mohla mít potenciál některé tyto nedostatky zmírnit či zcela eliminovat. To by zároveň vedlo nejen ke zkrácení potřebného času, ale především ke zpřesnění vyšetřování podobných případů. V souladu s tím informace v literatuře naznačují, že komplexnější zobrazení těchto patologií by mohlo představovat určitý pokrok. Není dosud zcela jasné použití u osob ve vážném stavu, akutních situacích, při aktuální nemožnosti provést vyšetření jícnovou sondou či kontraindikacích k převozu na jinou zobrazovací metodu. Článek popisuje využití této metody na našem pracovišti při stanovení diagnózy u konkrétních pacientů. Jedná se o tři různé klinické jednotky, v běžné praxi v této formě a rozsahu poměrně raritní. Ve všech případech byl použit přístroj SONOS 7 500 a matrixová ultrazvuková sonda X4 (firma Philips, Andover, MA, USA).
Echocardiography is a method used routinely also in the diagnosis of intracardiac formations. Two-dimensional visualization of fast-moving pathological structures within cardiac chambers is fraught with a variety of specific problems and limitations. Their visualization, not always ideal during standard ultrasound examination, still poses a challenge, as an erroneous conclusion and a misdiagnosis may have serious implications for the patient. In theory, three-dimensional real-time echocardiography could mitigate or even completely eliminate some of these shortcomings. This would result not only in shortening procedural time but, also, in improving the examination in similar cases. Consistent with this, literary data suggest a more comprehensive visualization of these pathologies would be a step forward. Potential utility of three-dimensional real-time echocardiography in the critically-ill, in acute states, in settings not allowing examination by esophageal probe or when use of another imaging method is contraindicated is yet to be defined. The paper describes the use of this method in our department for establishing diagnosis in specific patients with three different clinical entities, fairly rare in everyday practice in terms of the form and extent. A SONOS 7500 system with an X4 matrix ultrasound probe were used in all cases (Philips, Andover, MA, USA).
- MeSH
- Diagnostic Techniques, Cardiovascular utilization MeSH
- Echocardiography, Three-Dimensional methods utilization MeSH
- Embolism and Thrombosis diagnosis etiology ultrasonography MeSH
- Cardiovascular Abnormalities diagnosis etiology ultrasonography MeSH
- Heart Neoplasms diagnosis etiology ultrasonography MeSH
- Heart Diseases diagnosis etiology ultrasonography MeSH
- Papillary Muscles injuries MeSH
- Pulmonary Embolism diagnosis etiology surgery MeSH
- Thrombolytic Therapy methods utilization MeSH
- Publication type
- Case Reports MeSH
The Lon protein is a protease belonging to the superfamily of ATPases associated with diverse cellular activities (AAA+). Its main function is the control of protein quality and the maintenance of proteostasis by degradation of misfolded and damaged proteins, which occur in response to numerous stress conditions. It also participates in the regulation of levels of transcription factors that control pathogenesis, development and stress response. We focus our interest on the structure of human mitochondrial Lon (hLon) protease, whose altered expression levels are linked to some severe diseases such as epilepsy, myopathy, or lateral sclerosis. We present the first 3D structure of the ADP-bound human Lon S885A mutant obtained by electron microscopy as a result of preliminary negative staining studies. S885A appears as a hexameric ring of 120 Å diameter having 90 Å in height. Its resolution was estimated at 19 Å by the FSC = 0.5 criterion. This model is a primary step towards the understanding of the mechanism of action of the Lon protease and its involvement in the pathogenesis development.
Neuronal activity and many pathological states in the CNS are accompanied by transient astrocytic swelling, which affects excitability, extrasynaptic transmission, and neuron-glia interactions. By using three-dimensional confocal morphometry (3DCM), we quantified the morphometric parameters of astrocytes in intact tissue. In experiments performed in brain cortex slices from transgenic GFAP/EGFP mice, we applied 3DCM to study the dynamic changes in astrocyte morphology during hypotonic stress. Our morphometric analysis showed that the effect of a 10-min application of hypotonic solution (200 mmol/kg) on the swelling of different cell compartments was dependent on the extent of the swelling of the total astrocyte volume. If the swelling of the whole cell, i.e., soma and processes, was less than approximately 10%, there were no differences between the swelling of the soma and the processes. However, if the swelling of the total cell volume was greater than 10%, the swelling of the processes was greater than the swelling of the soma. Analyzing the effect of hypotonic solution on the morphology of these astrocytes revealed that the total cell volume increased; however, certain cell compartments were distinguished in which the volume increased, whereas in other compartments cell volume decreased or apparently did not change, and the structure of some compartments was altered. Our data show that astrocytes in brain slices undergoing hypotonic stress display cell volume regulation as well as transient changes in morphology.
- MeSH
- Astrocytes ultrastructure MeSH
- Financing, Organized MeSH
- Glial Fibrillary Acidic Protein genetics MeSH
- Hypotonic Solutions MeSH
- Microscopy, Confocal MeSH
- Brain ultrastructure MeSH
- Mice, Transgenic MeSH
- Mice MeSH
- Organ Culture Techniques MeSH
- Image Processing, Computer-Assisted MeSH
- Promoter Regions, Genetic MeSH
- Green Fluorescent Proteins genetics MeSH
- Imaging, Three-Dimensional MeSH
- Animals MeSH
- Check Tag
- Mice MeSH
- Animals MeSH
In organized tissues, the precise geometry and the overall shape are critical for the specialized functions that the cells carry out. Odontoblasts are major matrix-producing cells of the tooth and have also been suggested to participate in sensory transmission. However, refined morphologic data on these important cells are limited, which hampers the analysis and understanding of their cellular functions. We took advantage of fluorescent color-coding genetic tracing to visualize and reconstruct in 3 dimensions single odontoblasts, pulp cells, and their assemblages. Our results show distinct structural features and compartments of odontoblasts at different stages of maturation, with regard to overall cellular shape, formation of the main process, orientation, and matrix deposition. We demonstrate previously unanticipated contacts between the processes of pulp cells and odontoblasts. All reported data are related to mouse incisor tooth. We also show that odontoblasts express TRPM5 and Piezo2 ion channels. Piezo2 is expressed ubiquitously, while TRPM5 is asymmetrically distributed with distinct localization to regions proximal to and within odontoblast processes.
- MeSH
- Ameloblasts cytology ultrastructure MeSH
- Cell Nucleus ultrastructure MeSH
- Cell Surface Extensions ultrastructure MeSH
- Dentin ultrastructure MeSH
- Extracellular Matrix ultrastructure MeSH
- Fluorescent Antibody Technique MeSH
- Ion Channels ultrastructure MeSH
- TRPM Cation Channels ultrastructure MeSH
- Cell Compartmentation MeSH
- Mesenchymal Stem Cells cytology ultrastructure MeSH
- Microscopy, Electron, Scanning methods MeSH
- Mice, Transgenic MeSH
- Mice MeSH
- Odontoblasts cytology ultrastructure MeSH
- Incisor cytology ultrastructure MeSH
- Cell Shape MeSH
- Imaging, Three-Dimensional methods MeSH
- Dental Pulp cytology ultrastructure MeSH
- Animals MeSH
- Check Tag
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Pathological states in the central nervous system lead to dramatic changes in the activity of neuroactive substances in the extracellular space, to changes in ionic homeostasis and often to cell swelling. To quantify changes in cell morphology over a certain period of time, we employed a new technique, three-dimensional confocal morphometry. In our experiments, performed on enhanced green fluorescent protein/glial fibrillary acidic protein astrocytes in brain slices in situ and thus preserving the extracellular microenvironment, confocal morphometry revealed that the application of hypotonic solution evoked two types of volume change. In one population of astrocytes, hypotonic stress evoked small cell volume changes followed by a regulatory volume decrease, while in the second population volume changes were significantly larger without subsequent volume regulation. Three-dimensional cell reconstruction revealed that even though the total astrocyte volume increased during hypotonic stress, the morphological changes in various cell compartments and processes were more complex than have been previously shown, including swelling, shrinking and structural rearrangement. Our data show that astrocytes in brain slices in situ during hypotonic stress display complex behaviour. One population of astrocytes is highly capable of cell volume regulation, while the second population is characterized by prominent cell swelling, accompanied by plastic changes in morphology. It is possible to speculate that these two astrocyte populations play different roles during physiological and pathological states.
- MeSH
- Astrocytes pathology ultrastructure MeSH
- Financing, Organized MeSH
- Animals, Genetically Modified MeSH
- Glial Fibrillary Acidic Protein analysis MeSH
- Microscopy, Confocal methods MeSH
- Humans MeSH
- Models, Animal MeSH
- Brain pathology ultrastructure MeSH
- Mice MeSH
- Brain Diseases pathology MeSH
- Green Fluorescent Proteins MeSH
- Imaging, Three-Dimensional MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Mice MeSH
- Animals MeSH
- Publication type
- Review MeSH
Terrestrial laser scanning is a powerful technology for capturing the three-dimensional structure of forests with a high level of detail and accuracy. Over the last decade, many algorithms have been developed to extract various tree parameters from terrestrial laser scanning data. Here we present 3D Forest, an open-source non-platform-specific software application with an easy-to-use graphical user interface with the compilation of algorithms focused on the forest environment and extraction of tree parameters. The current version (0.42) extracts important parameters of forest structure from the terrestrial laser scanning data, such as stem positions (X, Y, Z), tree heights, diameters at breast height (DBH), as well as more advanced parameters such as tree planar projections, stem profiles or detailed crown parameters including convex and concave crown surface and volume. Moreover, 3D Forest provides quantitative measures of between-crown interactions and their real arrangement in 3D space. 3D Forest also includes an original algorithm of automatic tree segmentation and crown segmentation. Comparison with field data measurements showed no significant difference in measuring DBH or tree height using 3D Forest, although for DBH only the Randomized Hough Transform algorithm proved to be sufficiently resistant to noise and provided results comparable to traditional field measurements.
- MeSH
- Algorithms MeSH
- Automation MeSH
- Forests * MeSH
- Imaging, Three-Dimensional * MeSH
- Publication type
- Journal Article MeSH
