The connectivities of all atoms in ascorbigen A, an important metabolite, were determined unambiguously for the first time. The connectivity between carbon atoms was established by 2D INADEQUATE, and one-bond 13 C-13 C coupling constants were determined for all pairs of directly connected carbon atoms except for two strongly coupled carbon pairs. The 13 C-13 C coupling in one of the pairs was proved by a modification of standard INADEQUATE; however, the signals from the other pair were too weak to be observed. The connectivity within the two strongly coupled C-C pairs was confirmed by a combination of COSY and gHSQC; the latter experiment also identified all C-H bonds. The proton nuclear magnetic resonance (1 H NMR) spectra in dry dimethyl sulfoxide allowed identification and assignment of the signals due to NH and OH protons. The derived structure, 3-((1H-indol-3-yl)methyl)-3,3a,6-trihydroxytetrahydrofuro[3,2-b]furan-2(5H)-one, agrees with the structure suggested for ascorbigen A in 1966. The density functional theory (DFT) calculations showed that among 16 possible stereoisomers, only two complied with the almost zero value of the measured 3 J(H6-H6a). Of the two stereoisomers, 3S,3aS,6S,6aR and 3R,3aR,6R,6aS, the latter was excluded on synthetic grounds. The nuclear Overhauser effect measurements unveiled close proximity between H2' proton of the indole and the H6a proton of the tetrahydrofuro[3,2-b]furan part. Detailed structural interpretation of the measured NMR parameters by means of DFT NMR was hampered by rotational flexibility of the indole and tetrahydrofuro[3,2-b]furan parts and inadequacy of Polarizable Continuum Model (PCM) solvent model.

• Klíčová slova
• 13C NMR, 13C-13C coupling constants, 13C-1H coupling constants, 1H NMR, 1H-1H coupling constants, NMR, NOE, natural product, rotamers, stereochemistry,
• MeSH
• indoly analýza   MeSH
• kyselina askorbová analogy a deriváty   analýza   MeSH
• magnetická rezonanční spektroskopie MeSH
• molekulární konformace MeSH
• teorie funkcionálu hustoty MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• ascorbigen MeSH Prohlížeč
• indoly MeSH
• kyselina askorbová MeSH

Signal enhancements of up to two orders of magnitude in protein NMR can be achieved by employing HDO as a vector to introduce hyperpolarization into folded or intrinsically disordered proteins. In this approach, hyperpolarized HDO produced by dissolution-dynamic nuclear polarization (D-DNP) is mixed with a protein solution waiting in a high-field NMR spectrometer, whereupon amide proton exchange and nuclear Overhauser effects (NOE) transfer hyperpolarization to the protein and enable acquisition of a signal-enhanced high-resolution spectrum. To date, the use of this strategy has been limited to 1D and 1H-15N 2D correlation experiments. Here we introduce 2D 13C-detected D-DNP, to reduce exchange-induced broadening and other relaxation penalties that can adversely affect proton-detected D-DNP experiments. We also introduce hyperpolarized 3D spectroscopy, opening the possibility of D-DNP studies of larger proteins and IDPs, where assignment and residue-specific investigation may be impeded by spectral crowding. The signal enhancements obtained depend in particular on the rates of chemical and magnetic exchange of the observed residues, thus resulting in non-uniform 'hyperpolarization-selective' signal enhancements. The resulting spectral sparsity, however, makes it possible to resolve and monitor individual amino acids in IDPs of over 200 residues at acquisition times of just over a minute. We apply the proposed experiments to two model systems: the compactly folded protein ubiquitin, and the intrinsically disordered protein (IDP) osteopontin (OPN).

• Klíčová slova
• 3D NMR, BEST-HNCO, Direct 13C detection, Dissolution-dynamic nuclear polarization (D-DNP), Hyperpolarization, Non-uniform sampling,
• MeSH
• lidé MeSH
• nukleární magnetická rezonance biomolekulární * MeSH
• osteopontin chemie   MeSH
• ubikvitin chemie   MeSH
• vnitřně neuspořádané proteiny chemie   MeSH
• voda chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• osteopontin MeSH
• SPP1 protein, human MeSH Prohlížeč
• ubikvitin MeSH
• vnitřně neuspořádané proteiny MeSH
• voda MeSH

We report a new multidimensional magic angle spinning NMR methodology, which provides an accurate and detailed probe of molecular motions occurring on timescales of nano- to microseconds, in sidechains of proteins. The approach is based on a 3D CPVC-RFDR correlation experiment recorded under fast MAS conditions (ν(R) = 62 kHz), where (13)C-(1)H CPVC dipolar lineshapes are recorded in a chemical shift resolved manner. The power of the technique is demonstrated in model tripeptide Tyr-(d)Ala-Phe and two nanocrystalline proteins, GB1 and LC8. We demonstrate that, through numerical simulations of dipolar lineshapes of aromatic sidechains, their detailed dynamic profile, i.e., the motional modes, is obtained. In GB1 and LC8 the results unequivocally indicate that a number of aromatic residues are dynamic, and using quantum mechanical calculations, we correlate the molecular motions of aromatic groups to their local environment in the crystal lattice. The approach presented here is general and can be readily extended to other biological systems.

• MeSH
• cytoplazmatické dyneiny chemie   MeSH
• izotopy uhlíku chemie   MeSH
• kvantová teorie MeSH
• molekulární modely MeSH
• nukleární magnetická rezonance biomolekulární MeSH
• peptidy chemie   MeSH
• receptory GABA-B chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• cytoplazmatické dyneiny MeSH
• izotopy uhlíku MeSH
• peptidy MeSH
• receptory GABA-B MeSH

UNLABELLED: Nowadays 3D printing allows us to create physical objects on the basis of digital data. Thanks to its rapid development the use enormously increased in medicine too. Its creations facilitate surgical planning processes, education and research in context of organ transplantation, individualization prostheses, breast forms, and others.Our article describes the wide range of applied 3D printing technology possibilities in ophthalmology. It is focusing on innovative implementation of eye tumors treatment planning in stereotactic radiosurgery irradiation.We analyze our first experience with 3D printing model of the eye in intraocular tumor planning stereotactic radiosurgery. KEY WORDS: 3D printing, model, Fused Deposition Modelling, stereotactic radiosurgery, prostheses, intraocular tumor.

• MeSH
• 3D tisk statistika a číselné údaje   MeSH
• biologické modely MeSH
• lidé MeSH
• magnetická rezonanční tomografie MeSH
• nádory oka radioterapie   MeSH
• oftalmologie MeSH
• plánování radioterapie pomocí počítače MeSH
• radiochirurgie metody   MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Most of our knowledge of protein structure and function originates from experiments performed with purified proteins resuspended in dilute, buffered solutions. However, most proteins function in crowded intracellular environments with complex compositions. Significant efforts have been made to develop tools to study proteins in their native cellular settings. Among these tools, in-cell NMR spectroscopy has been the sole technique for characterizing proteins in the intracellular space of living cells at atomic resolution and physiological temperature. Nevertheless, due to technological constraints, in-cell NMR studies have been limited to asynchronous single-cell suspensions, precluding obtaining information on protein behavior in different cellular states. In this study, we present a methodology that allows for obtaining an atomically resolved NMR readout of protein structure and interactions in living human cells synchronized in specific cell cycle phases and within 3D models of human tissue. The described approach opens avenues for investigating how protein structure or drug recognition responds to cell-cell communication or changes in intracellular space composition during transitions among cell cycle phases.

• MeSH
• buněčný cyklus * MeSH
• konformace proteinů MeSH
• lidé MeSH
• magnetická rezonanční spektroskopie metody   MeSH
• proteiny * chemie   metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• proteiny * MeSH

BACKGROUND: Uterovaginal brachytherapy planning is conventionally based on the use of two orthogonal Xray projections. Currently, there is a large development of 3D brachytherapy planning based on the fusion of CT and MRI, which takes into account the extent of the tumor and the location of organs at risk. In this work, we evaluated the dosimetric data and first clinical results in patients with inoperable cervical cancer using MRI/ CT compatible applicator enabling 3D planning. PATIENTS AND METHODS: Between June 2012 and March 2013, we performed 52 uterovaginal applications in 13 patients with inoperable cervical cancer using Vienna Ring MR CT applicator. Planning was carried out by the fusion of MRI and CT. Target volumes and organs at risk delineation were carried out on the basis of GEC ESTRO and ABS recommendations as well as doses report-ing. RESULTS: Overall radiotherapy duration was 37- 52 days with median of 45 days. The median total dose delivered to the HR CTV was 88 Gy (70.7- 97.9) EQD2. The median single dose in brachytherapeutic applications was D90 = 6.45 Gy (3.2- 9.82). The median total doses delivered to the rectum, sigmoid colon and bladder were D2ccrectum = 64.2 Gy (54.3- 74.1), D2ccsigmoid = 68.6 Gy (57- 74.7) a D2ccbladder = 73.9 Gy (58.3- 92.6). In 11 patients (84.6%), complete locoregional remission was achieved, in the remaining two patients (15.4%), partial locoregional remission was achieved. Twelve patients (92.3%) had complete regression of the tumor in the cervix, one patient (7.7%) developed metastatic spread to the liver. Yet we did not observe manifestations of a higher degree of toxicity than the first grade, both GI and GU. Late GI toxicity was manifested in two patients (15.4%) and late GU toxicity was manifested in five patients (38.5%). CONCLUSION: 3D brachytherapy planning of inoperable cervical cancer using the fusion of MRI and CT conclusively raises the possibility of the dose escalation to the tumor and significantly spares the surrounding organs at risk. Subsequently, this way of planning leads to better local control of the disease and to lower radiation morbidity.

• MeSH
• brachyterapie metody   MeSH
• celková dávka radioterapie MeSH
• dospělí MeSH
• intervenční radiografie MeSH
• kombinovaná terapie MeSH
• lidé středního věku MeSH
• lidé MeSH
• magnetická rezonanční tomografie metody   MeSH
• nádory děložního čípku diagnostické zobrazování   patologie   radioterapie   MeSH
• plánování radioterapie pomocí počítače * MeSH
• senioři MeSH
• staging nádorů MeSH
• stupeň nádoru MeSH
• zobrazování trojrozměrné MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Brachytherapy plays a major role in the therapeutic management of patiens with cervix cancer. The rapid dose fall-off provide a very high dose to the tumor, while relative sparing bladder, rektum, sigmoid and small bowel. The CT/MR-based planning provides better information on target and organ volumes and dose-volumes histograms in contrast to radiography-based planning, that provides doses only at selected points.

• MeSH
• brachyterapie * MeSH
• celková dávka radioterapie MeSH
• lidé MeSH
• magnetická rezonanční tomografie * MeSH
• nádory děložního čípku radioterapie   MeSH
• plánování radioterapie pomocí počítače * MeSH
• počítačová rentgenová tomografie * MeSH
• zobrazování trojrozměrné MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH

Improving our understanding of nanosecond motions in disordered proteins requires the enhanced sampling of the spectral density function obtained from relaxation at low magnetic fields. High-resolution relaxometry and two-field NMR measurements of relaxation have, so far, only been based on the recording of one- or two-dimensional spectra, which provide insufficient resolution for challenging disordered proteins. Here, we introduce a 3D-HNCO-based two-field NMR experiment for measurements of protein backbone 15 N amide longitudinal relaxation rates. The experiment provides accurate longitudinal relaxation rates at low field (0.33 T in our case) preserving the resolution and sensitivity typical for high-field NMR spectroscopy. Radiofrequency pulses applied on six different radiofrequency channels are used to manipulate the spin system at both fields. The experiment was demonstrated on the C-terminal domain of δ subunit of RNA polymerase from Bacillus subtilis, a protein with highly repetitive amino-acid sequence and very low dispersion of backbone chemical shifts.

• Klíčová slova
• Dynamics, High-resolution relaxometry, Intrinsically disordered proteins, Non-uniform sampling, Nuclear magnetic resonance, Relaxation,
• MeSH
• Bacillus subtilis enzymologie   MeSH
• bakteriální proteiny chemie   MeSH
• DNA řízené RNA-polymerasy chemie   MeSH
• nukleární magnetická rezonance biomolekulární * MeSH
• rekombinantní proteiny chemie   MeSH
• vnitřně neuspořádané proteiny chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• bakteriální proteiny MeSH
• DNA řízené RNA-polymerasy MeSH
• rekombinantní proteiny MeSH
• vnitřně neuspořádané proteiny MeSH

Congenital epulis is a rare benign oral cavity tumor that usually arises from the maxillary alveolar mucosa. It is also known as congenital gingival granular cell tumor. Prenatal diagnosis is uncommon and mostly confined to the third trimester. We report a case of congenital epulis, which was referred to our department at 35 weeks of gestation. Both images from our prenatal 2D/3D ultrasound (including Doppler technique) and magnetic resonance examination are presented. A baby girl weighing 2,800 g was delivered spontaneously at 36 weeks and 1 day. The newborn had to be intubated immediately after delivery. A simple excision of the mass was performed on the first day of neonatal life after clinical examination by our pediatric stomatologists confirmed the presence of a tumor resembling epulis. The correctness of this diagnosis was subsequently confirmed by histogenesis. Photographs from the operating room show the postnatal appearance of the tumor. The baby was discharged at the age of 19 days and has remained well at follow-up controls.

• MeSH
• dospělí MeSH
• lidé MeSH
• magnetická rezonanční tomografie MeSH
• nádor z granulárních buněk diagnóza   diagnostické zobrazování   embryologie   chirurgie   MeSH
• nádory dásní diagnóza   diagnostické zobrazování   embryologie   chirurgie   MeSH
• novorozenec MeSH
• prenatální diagnóza * MeSH
• těhotenství MeSH
• třetí trimestr těhotenství MeSH
• ultrasonografie dopplerovská barevná MeSH
• ultrasonografie prenatální MeSH
• výsledek terapie MeSH
• zobrazování trojrozměrné MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• novorozenec MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• práce podpořená grantem MeSH

The 1H and 13C NMR chemical shifts of cis- and trans-protopinium salts were measured and calculated. The calculations of the chemical shifts consisted of conformational analysis, geometry optimization (RHF/6-31G** method) and shielding constants calculations (B3LYP/6-31G** method). Based on the results of the quantum chemical calculations, two sets of experimental chemical shifts were assigned to the particular isomers. According to the experimental results, the trans-isomer is more stable and its population is approximately 68%.

• MeSH
• benzofenantridiny MeSH
• berberinové alkaloidy analýza   chemie   MeSH
• chemické modely * MeSH
• isomerie MeSH
• izotopy uhlíku MeSH
• magnetická rezonanční spektroskopie metody   MeSH
• molekulární konformace MeSH
• molekulární modely * MeSH
• počítačová simulace MeSH
• protony MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• benzofenantridiny MeSH
• berberinové alkaloidy MeSH
• izotopy uhlíku MeSH
• protony MeSH
• protopine MeSH Prohlížeč