Elevated levels of galectin-3 are associated with tumorigenesis. Its inhibition with high-affinity carbohydrate ligands opens new therapeutic routes. Targeting of intracellular galectin-3 is challenging for polar inhibitors like carbohydrates. We demonstrate the potential of novel biomedical research tools, glycocalix[4]arenes, to enter epithelial cells, which may allow their interaction with galectin-3.

• MeSH
• buněčná membrána MeSH
• galektin 3 * MeSH
• galektiny MeSH
• glykokalyx * MeSH
• sacharidy farmakologie   MeSH
• Publikační typ
• časopisecké články MeSH

In 1959, P. Karlson and M. Lüscher introduced the term 'pheromone', broadly used nowadays for various chemicals involved in intraspecific communication. To demonstrate the term, they depicted the situation in termite societies, where king and queen inhibit the reproduction of nest-mates by an unknown chemical substance. Paradoxically, half a century later, neither the source nor the chemical identity of this 'royal' pheromone is known. In this study, we report for the first time the secretion of polar compounds of proteinaceous origin by functional reproductives in three termite species, Prorhinotermes simplex, Reticulitermes santonensis and Kalotermes flavicollis. Aqueous washes of functional reproductives contained sex-specific proteinaceous compounds, virtually absent in non-reproducing stages. Moreover, the presence of these compounds was clearly correlated with the age of reproductives and their reproductive status. We discuss the putative function of these substances in termite caste recognition and regulation.

• MeSH
• hmyzí proteiny chemie   metabolismus   MeSH
• Isoptera klasifikace   fyziologie   MeSH
• rozmnožování MeSH
• sociální hierarchie MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
• uhlovodíky analýza   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• Publikační typ
• abstrakty MeSH

A novel antimicrobial peptide designated melectin was isolated from the venom of the cleptoparasitic bee Melecta albifrons. Its primary sequence was established as H-Gly-Phe-Leu-Ser-Ile-Leu-Lys-Lys-Val-Leu-Pro-Lys-Val-Met-Ala-His-Met-Lys-NH(2) by Edman degradation and ESI-QTOF mass spectrometry. Synthetic melectin exhibited antimicrobial activity against both gram-positive and -negative bacteria and it degranulated rat peritoneal mast cells, but its hemolytic activity was low. The CD spectra of melectin measured in the presence of trifluoroethanol and sodium dodecyl sulfate showed a high content alpha-helices, which indicates that melectin can adopt an amphipathic alpha-helical secondary structure in an anisotropic environment such as the bacterial cell membrane. To envisage the role of the proline residue located in the middle of the peptide chain on biological activity and secondary structure, we prepared several melectin analogues in which the Pro11 residue was either replaced by other amino acid residues or was omitted. The results of biological testing suggest that a Pro kink in the alpha-helical structure of melectin plays an important role in selectivity for bacterial cells. In addition, a series of N- and C-terminal-shortened analogues was synthesized to examine which region of the peptide is related to antimicrobial activity.

• MeSH
• antibakteriální látky farmakologie   chemická syntéza   izolace a purifikace   MeSH
• cirkulární dichroismus MeSH
• degranulace buněk účinky léků   MeSH
• erytrocyty účinky léků   MeSH
• gramnegativní bakterie účinky léků   MeSH
• grampozitivní bakterie účinky léků   MeSH
• hemolýza účinky léků   MeSH
• hydrofobní a hydrofilní interakce MeSH
• inhibiční koncentrace 50 MeSH
• kationické antimikrobiální peptidy farmakologie   chemická syntéza   izolace a purifikace   MeSH
• krysa rodu rattus MeSH
• mastocyty fyziologie   účinky léků   MeSH
• mikrobiální testy citlivosti MeSH
• molekulární sekvence - údaje MeSH
• potkani Wistar MeSH
• sekundární struktura proteinů MeSH
• sekvence aminokyselin MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
• včelí jedy chemie   MeSH
• včely MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• zvířata MeSH
• Publikační typ
• práce podpořená grantem MeSH

Herein, we report the use of the Suzuki-Miyaura cross-coupling reaction for the preparation of a library of synthetic derivatives of flavonoids for biological activity assays. We have investigated the reactivity of halogenated flavonoids with aryl boronates and with boronyl flavonoids. This reaction was used to prepare new synthetic derivatives of flavonoids substituted at C-8 with aryl, heteroaryl, alkyl, and boronate substituents. The formation of flavonoid boronate enabled a cross-coupling reaction with halogenated flavones yielding biflavonoids connected at C-8. This method was used for the preparation of natural compounds including C-8 prenylated compounds, such as sinoflavonoid NB. Flavonoid boronates were used for the preparation of rare C-8 hydroxyflavonoids (natural flavonoids gossypetin and hypolaetin). A series of previously unknown derivatives of quercetin and luteolin were prepared and fully characterized.

• MeSH
• flavonoidy chemie   MeSH
• katalýza MeSH
• kyseliny boronové chemie   MeSH
• luteolin chemie   MeSH
• molekulární struktura MeSH
• palladium chemie   MeSH
• quercetin chemie   MeSH
• Publikační typ
• časopisecké články MeSH

In an attempt to prepare a library of short oligoadenylate analogues featuring both the enzyme-stable internucleotide linkage and the 5'-O-methylphosphonate moiety and thus obtain a pool of potential RNase L agonists/antagonists, we studied the spontaneous polycondensation of the adenosin-5'-O-ylmethylphosphonic acid (p(c)A), an isopolar AMP analogue, and its imidazolide derivatives employing N,N'-dicyclohexylcarbodiimide under nonaqueous conditions and uranyl ions under aqueous conditions, respectively. The RP LC-MS analyses of the reaction mixtures per se, and those obtained after the periodate treatment, along with analyses and separations by capillary zone electrophoresis, allowed us to characterize major linear and cyclic oligoadenylates obtained. The structure of selected compounds was supported, after their isolation, by NMR spectroscopy. Ab initio calculation of the model structures simulating the AMP-imidazolide and p(c)A-imidazolide offered the explanation why the latter compound exerted, in contrast to AMP-imidazolide, a very low stability in aqueous solutions.

• MeSH
• adeninnukleotidy chemie   metabolismus   MeSH
• adenosinmonofosfát analogy a deriváty   MeSH
• molekulární modely MeSH
• molekulární struktura MeSH
• nukleární magnetická rezonance biomolekulární MeSH
• oligoribonukleotidy chemie   metabolismus   MeSH
• oxidace-redukce MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

We investigated peroxidase-mediated oxidation of and the formation of the (deoxy)guanosine adduct by 1-phenylazo-2-hydroxynaphthalene (Solvent Yellow 14, Sudan I), a liver and urinary bladder carcinogen for rodents and a potent contact allergen and sensitizer for humans. Using thin layer chromatography (TLC) and/or high performance liquid chromatography (HPLC) combined with mass and/or nuclear magnetic resonance (NMR) spectrometry, we characterized the structures of two major peroxidase-mediated Sudan I metabolites and those of the adducts of (deoxy)guanosine that are formed during Sudan I oxidation. Peroxidase oxidizes Sudan I to radical species that react with another Sudan I radical to form the Sudan I dimer, or in the presence of (deoxy)guanosine, the oxidized Sudan I can attack the exocyclic amino group of guanine, forming the 4-[(deoxy)guanosin-N(2)-yl]Sudan I adduct. The reaction product with a second Sudan I radical results in a dimer where the oxygen 2 radical of Sudan I reacted with carbon 1 in the second Sudan I skeleton. The Sudan I dimer is unstable and decomposes spontaneously to the second oxidation product. This compound consists of the 4-oxo-Sudan I skeleton connected via the oxygen of its 2-hydroxyl group and nitrogen of its azo group with carbon 1 of 2-oxonaphthalene, having a unique spironaphthooxadiazine structure. If (deoxy)guanosine is present during the formation of this Sudan I metabolite, an adduct, in which this Sudan I metabolite is bound to the exocyclic amino group of guanine, is generated. This (deoxy)guanosine adduct is again unstable and decomposes spontaneously to the same adduct that is formed by the direct reaction of oxidized Sudan I, the 4-[(deoxy)guanosin-N(2)-yl]Sudan I adduct. The results presented here are the first structural characterization of Sudan I-(deoxy)guanosine adducts formed during the oxidation of this carcinogen by peroxidase.

• MeSH
• adukty DNA chemie   MeSH
• barvicí látky chemie   metabolismus   toxicita   MeSH
• biokatalýza MeSH
• deoxyguanosin chemie   metabolismus   MeSH
• karcinogeny chemie   metabolismus   toxicita   MeSH
• naftoly chemie   metabolismus   toxicita   MeSH
• oxidace-redukce MeSH
• peroxidasa metabolismus   MeSH
• Publikační typ
• práce podpořená grantem MeSH

• Publikační typ
• abstrakty MeSH

Eight C-6-geranylflavonoids ( 1- 8) were isolated from an ethanol extract of Paulownia tomentosa fruits. Tomentodiplacone ( 1), 3'- O-methyl-5'-hydroxydiplacone ( 2), 3'- O-methyl-5'- O-methyldiplacone ( 3), and tomentodiplacone B ( 4) were obtained as new compounds, and 3'- O-methyldiplacol ( 5) was isolated for the first time from a natural source. The structures of these new compounds were determined by using mass spectrometry (including HRMS) and 1D and 2D NMR spectroscopy, and the absolute configurations of the compounds were determined by circular dichroism. The antibacterial activities of 1- 8 against seven bacteria and yeast were evaluated.

• MeSH
• antibakteriální látky farmakologie   chemie   izolace a purifikace   MeSH
• Bacteria účinky léků   MeSH
• Candida albicans účinky léků   MeSH
• cirkulární dichroismus MeSH
• financování organizované MeSH
• flavonoidy farmakologie   chemie   izolace a purifikace   MeSH
• léčivé rostliny chemie   MeSH
• mikrobiální testy citlivosti MeSH
• molekulární struktura MeSH
• nukleární magnetická rezonance biomolekulární MeSH
• ovoce chemie   MeSH
• Scrophulariaceae chemie   MeSH
• Geografické názvy
• Česká republika MeSH

Analýza proteomu zhoubných nádorů prsu. Zjišťování nových faktorů efektivity léčby a selhání léčby s cílem zlepšit dosavadní léčebné výsledky. Vztah nových faktorů a stávajících prognostických a prediktivních faktorů. Kultivace nádorů in vitro. Data získaná v rámci projektu budou zpracována metodou explorační analýzy dat GUHA. Tato metoda umožňuje automatickou tvorbu a testování hypotéz o skutečnostech podporovaných daty.; Analysis of the proteome of malignant breast tumors. Determination of novel prognostic and predictive factors.The validity of the classical prognostic factors versus molecular prognostic factors will be determined. Statistical analysis of breast cancer patients using GUHA method. General Unary Hypotheses Automaton method of exploration data analysis.

• MeSH
• management nemoci MeSH
• nádorové biomarkery analýza   MeSH
• nádory prsu terapie   MeSH
• přežití bez známek nemoci MeSH
• prognóza MeSH
• proteom analýza   MeSH

• Konspekt
• Patologie. Klinická medicína
• NLK Obory
• gynekologie a porodnictví
• onkologie
• NLK Publikační typ
• závěrečné zprávy o řešení grantu IGA MZ ČR