The monophyodont molar teeth, prismatic enamel and the complexity of enamel microarchitecture are regarded as essential dental apomorphies of mammals. As prominent background factors of feeding efficiency and individual longevity these characters are crucial components of mammalian adaptive dynamics. Little is known, however, to which degree these adaptations are influenced by the crystallographic properties of elementary hydroxyapatite crystallites, the only inorganic component of enamel. In a miniature pig where individual molars differ significantly in duration of their development and in enamel resistance to attrition stress, we found highly significant differences between the molars in the size of crystallites, amount of microstrain, crystallinity and in enamel stiffness and elasticity, all clearly scaled with the duration of tooth calcification. The same pattern was found also in red deer bearing different molar type. The results suggest that the prolongation of tooth development is associated with an increase of crystallinity, i.e. the atomic order of enamel hydroxyapatite, an obvious component of micromechanical property of mature enamel. This relation could contribute to prolongation of dental development, characteristic of mammals in general. The aspects of enamel crystallinity, omitted in previous studies on mammalian and vertebrate dental evolution, are to be taken in account in these topics.

• MeSH
• apatity chemie   MeSH
• fyziologická adaptace * MeSH
• krystalografie MeSH
• miniaturní prasata MeSH
• moláry růst a vývoj   MeSH
• prasata MeSH
• prořezávání zubů fyziologie   MeSH
• zubní sklovina chemie   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• MeSH
• biokompatibilní potahované materiály terapeutické užití   MeSH
• fibroblasty fyziologie   MeSH
• financování organizované MeSH
• hydroxyapatit terapeutické užití   MeSH
• imunohistochemie využití   MeSH
• keratinocyty fyziologie   chemie   MeSH
• krystalizace metody   využití   MeSH
• lidé MeSH
• zubní implantáty trendy   využití   MeSH
• zubní materiály terapeutické užití   MeSH
• Check Tag
• lidé MeSH

• MeSH
• nukleové kyseliny metabolismus   MeSH
• oční čočka metabolismus   MeSH
• stárnutí * MeSH
• Publikační typ
• časopisecké články MeSH

Cnidaria is the earliest-branching metazoan phylum containing a well-developed, lens-containing visual system located on specialized sensory structures called rhopalia. Each rhopalium in a cubozoan jellyfish Tripedalia cystophora has a large and a small complex, camera-type eye with a cellular lens containing distinct families of crystallins. Here, we have characterized J2-crystallin and its gene in T. cystophora. The J2-crystallin gene is composed of a single exon and encodes a 157-amino acid cytoplasmic protein with no apparent homology to known proteins from other species. The non-lens expression of J2-crystallin suggests nonoptical as well as crystallin functions consistent with the gene-sharing strategy that has been used during evolution of lens crystallins in other invertebrates and vertebrates. Although nonfunctional in transfected mammalian lens cells, the J2-crystallin promoter is activated by the jellyfish paired domain transcription factor PaxB in co-transfection tests via binding to three paired domain sites. PaxB paired domain-binding sites were also identified in the PaxB-regulated promoters of the J1A- and J1B-crystallin genes, which are not homologous to the J2-crystallin gene. Taken together with previous studies on the regulation of the diverse crystallin genes, the present report strongly supports the idea that crystallin recruitment of multifunctional proteins was driven by convergent changes involving Pax (as well as other transcription factors) in the promoters of nonhomologous genes within and between species as well as within gene families.

• MeSH
• buněčné linie MeSH
• Cercopithecus aethiops MeSH
• COS buňky MeSH
• Cubozoa genetika   metabolismus   MeSH
• cytoplazma metabolismus   MeSH
• exony MeSH
• financování organizované MeSH
• klonování DNA MeSH
• krystaliny genetika   chemie   metabolismus   MeSH
• lidé MeSH
• molekulární evoluce MeSH
• molekulární sekvence - údaje MeSH
• oční čočka metabolismus   MeSH
• promotorové oblasti (genetika) MeSH
• regulace genové exprese MeSH
• sekvence nukleotidů MeSH
• transkripční faktory paired box genetika   metabolismus   metabolismus   MeSH
• vazebná místa MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH

• MeSH
• dítě MeSH
• heterozygot MeSH
• katarakta patologie   vrozené   MeSH
• konformace proteinů genetika   MeSH
• krystaliny genetika   chemie   MeSH
• lidé MeSH
• methionin genetika   nedostatek   MeSH
• oční čočka chemie   patologie   MeSH
• předškolní dítě MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• Publikační typ
• kazuistiky MeSH

• MeSH
• glykoproteiny MeSH
• haptoglobiny MeSH
• katalasa MeSH
• krystaliny MeSH
• krystalografie rentgenová MeSH
• lidé MeSH
• molekulární chaperony MeSH
• proteiny teplotního šoku MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• srovnávací studie MeSH

Some biologically active substances are unstable and poorly soluble in aqueous media, at the same time exhibiting low bioavailability. The incorporation of these biologically active compounds into the structure of a lipid-based lyotropic liquid crystalline phase or nanoparticles can increase or improve their stability and transport properties, subsequent bioavailability, and applicability in general. The aim of this short overview is (1) to clarify the principle of self-assembly of lipidic amphiphilic molecules in an aqueous environment and (2) to present lipidic bicontinuous cubic and hexagonal phases and their current biosensing (with a focus on electrochemical protocols) and biomedical applications.

• MeSH
• kapalné krystaly * chemie   MeSH
• lipidy chemie   MeSH
• nanočástice * chemie   MeSH
• technologie MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

Spectrometric-based surface-enhanced laser desorption/ionization ProteinChip (SELDI-TOF) facilitates rapid and easy analysis of protein mixtures and is often exploited to define potential diagnostic markers from sera. However, SELDI- TOF is a relatively insensitive technique and unable to detect circulating proteins at low levels even if they are differentially expressed in cancer patients. Therefore, we applied this technology to study tissues from renal cell carcinomas (RCC) in comparison to healthy controls. We found that different biomarkers are identified from tissues than those previously identified in serum, and that serum markers are often not produced by the tumors themselves at detectable levels, reflecting the nonspecific nature of many circulating biomarkers. We detected and characterized aB-crystallin as an overexpressed protein in RCC tissues and showed differential expression by immunohistochemistry. We conclude that SELDI-TOF is more useful for the identification of biomarkers that are synthesized by diseased tissues than for the identification of serum biomarkers and identifies a separate set of markers. We suggest that SELDI-TOF should be used to screen human cancer tissues to identify potential tissue-specific proteins and simpler and more sensitive techniques can then be applied to determine their validity as biomarkers in biological fluids.

• MeSH
• alfa-krystaliny - řetězec B analýza   krev   MeSH
• dospělí MeSH
• financování organizované MeSH
• imunohistochemie MeSH
• karcinom z renálních buněk diagnóza   chemie   krev   MeSH
• ledviny chemie   MeSH
• lidé MeSH
• nádorové biomarkery analýza   krev   MeSH
• nádory ledvin diagnóza   chemie   krev   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• senzitivita a specificita MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice metody   statistika a číselné údaje   MeSH
• studie případů a kontrol MeSH
• tkáňová distribuce MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• hodnotící studie MeSH

The most common complication following cataract surgery is posterior capsule opacification. This results from migration, proliferation and transdifferentiation of residual lens epithelial cells (LECs). We studied the effect of several culture substrates and culture conditions on LEC proliferation and ?-smooth muscle actin (?-SMA) expression. We used primary and secondary cultures of porcine LECs cultivated on collagen I, collagen IV, microscopic glass slides, and uncoated plastic dishes. We studied the cell proliferation and expression of ?-SMA and ?-, ß-, and ?-crystallins. The effect of the medium exchange protocol was studied using the TOTL-86 rabbit epithelial lens cell line. There was no difference in growth characteristics of primary cultures on different substrates. In secondary cultures, LECs adhered better to collagen-coated surfaces. The culture substrate influenced LEC proliferation and ?-SMA expression. The proliferation was greater when the medium was changed than when extra medium was added on the 4th day. The cells did not synthesize ?-, ß- or ?-crystallin. The culture substrate influences the adhesion ability, proliferation and ?-SMA expression in lens epithelial cells. In addition, it is necessary to consider the effects of the medium exchange protocol, serum supplementation, cell density and other cell culture conditions in lens epithelial cell experiments.

• MeSH
• aktiny metabolismus   MeSH
• alfa-krystaliny metabolismus   MeSH
• beta-krystaliny metabolismus   MeSH
• epitelové buňky cytologie   metabolismus   účinky léků   MeSH
• financování organizované MeSH
• gama-krystaliny metabolismus   MeSH
• imunohistochemie MeSH
• kolagen farmakologie   MeSH
• králíci MeSH
• kultivační média farmakologie   MeSH
• kultivované buňky MeSH
• myocyty hladké svaloviny účinky léků   MeSH
• oční čočka cytologie   MeSH
• prasata MeSH
• proliferace buněk účinky léků   MeSH
• regulace genové exprese účinky léků   MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• zvířata MeSH

The organisation of dinoflagellate chromosomes is exceptional among eukaryotes. Their genomes are the largest in the Eukarya domain, chromosomes lack histones and may exist in liquid crystalline state. Therefore, the study of the structural and functional properties of dinoflagellate chromosomes is of high interest. In this work, we have analysed the telomeres and telomerase in two Dinoflagellata species, Karenia papilionacea and Crypthecodinium cohnii. Active telomerase, synthesising exclusively Arabidopsis-type telomere sequences, was detected in cell extracts. The terminal position of TTTAGGG repeats was determined by in situ hybridisation and BAL31 digestion methods and provides evidence for the linear characteristic of dinoflagellate chromosomes. The length of telomeric tracts, 25-80 kb, is the largest among unicellular eukaryotic organisms to date. Both the presence of long arrays of perfect telomeric repeats at the ends of dinoflagellate chromosomes and the existence of active telomerase as the primary tool for their high-fidelity maintenance demonstrate the general importance of these structures throughout eukaryotes. We conclude that whilst chromosomes of dinoflagellates are unique in many aspects of their structure and composition, their telomere maintenance follows the most common scenario.

• MeSH
• chromatin genetika   metabolismus   MeSH
• chromozomy genetika   metabolismus   ultrastruktura   MeSH
• Dinoflagellata genetika   růst a vývoj   metabolismus   ultrastruktura   MeSH
• kapalné krystaly MeSH
• protozoální DNA genetika   MeSH
• repetitivní sekvence nukleových kyselin MeSH
• replikace DNA genetika   MeSH
• telomerasa metabolismus   MeSH
• telomery genetika   metabolismus   ultrastruktura   MeSH
• zlomy DNA MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH