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Structure of Free Radical inγ-Irradiated 21-Hydroxyprogesterone (Deoxycorticosterone) Single Crystals. ESR/ENDOR and DFT Studies

100%

Szyczewski A., Pietrzak J., Möbius K.

Acta Physica Polonica A

2005

vol. 108

issue 1

119-126

Single crystals of 21-hydroxyprogesterone have been γ-irradiated at 295 K and studied using X-band ESR and ENDOR. The structure of the one type radical has been determined on the basis of an analysis of the angular variation of the spectra. This radical is formed by abstraction of the hydrogen atom from the C(6) carbon, while the unpaired electron is delocalised onto the system O(3), C(3), C(4), C(5), C(6). Hyperfine splitting constants and unpaired electron density distribution have been calculated for the proposed radical structure by using the Gaussian98 set of programs. The results are in very good agreement with the experimental data. The effect of the hydrogen bond and biological activity on the anisotropy of α-hyperfine splitting tensor have also been discussed.

EPR Study of Gadolinium(III) Complexes with Heteropolyanions: [Gd(SiW_{11}O_{39})_{2}]^{13-} and [GdP_{5}W_{30}O_{110}]^{12-}

76%

Szyczewski A., Lis S., Kruczyński Z., Pietrzak J., But S., Elbanowski M.

Acta Physica Polonica A

1996

vol. 90

issue 2

345-351

The gadolinium complexes: [Gd(SiW_{11}O_{39})_{2}]^{13-} [I] and [GdP_{5}W_{30}O_{110}]^{12-} (Gd-encrypted Preyssler anion) [II] have been chosen for EPR study. This study is a continuation of our recent investigation related to solid gadolinium complexes: β-diketonates and aminopolycarboxylates. The EPR spectra of the Gd-polyoxometalates studied provide much better resolution than those recently studied. The spectra of Gd-polyoxometalates containing 1.7 to 2.5% of Gd(III) do not require an additional computer processing for correct interpretation. It is on the contrary to the β-diketonates and polyaminocarboxylates (with the content of Gd(III) 22-33%) for which the use of the RKU computer program (based on Fourier transform) was necessary in order to enhance the spectra resolution thus improving their correct interpretation. The EPR spectra obtained for the compounds I and II markedly differ from the U-spectrum characteristic of Gd(III) in glasses. Taking into account the spin-Hamiltonian calculations the existence of Gd(III) ion in two different surroundings: in a strong crystal field of rhombic symmetry and in a weak crystal field, is observed. The differences observed between the case I and II seem to be related to a various hydration degree.

Molecular cytogenetic characterization of eight small supernumerary marker chromosomes originating from chromosomes 2, 4, 8, 18, and 21 in three patients

52%

Pietrzak J., Mrasek K., Obersztyn E., Stankiewicz P., Kosyakova N., Weise A., Cheung S. W., Ca W. W., vo_ E. F., Mazurczak T., Bocian E., Liehr T.

Journal of Applied Genetics

2007

vol. 48

issue 2

167-175

Small supernumerary marker chromosomes (sSMCs) are a morphologically heterogeneous group of additional structurally abnormal chromosomes that cannot be identified unambiguously by conventional banding techniques alone. Molecular cytogenetic methods enable detailed characterization of sSMCs; however, in many cases interpretation of their clinical significance is problematic. The aim of our study was to characterize precisely sSMCs identified in three patients with dysmorphic features, psychomotor retardation and multiple congenital anomalies. We also attempted to correlate the patients' genotypes with phenotypes by inclusion of data from the literature. The sSMCs were initially detected by G-banding analysis in peripheral blood lymphocytes in these patients and were subsequently characterized using multicolor fluorescence in situ hybridization (M-FISH), (sub)centromere-specific multicolor FISH (cenM-FISH, subcenM-FISH), and multicolor banding (MCB) techniques. Additionally, the sSMCs in two patients were also studied by hybridization to whole-genome bacterial artificial chromosome (BAC) arrays (array-CGH) to map the breakpoints on a single BAC clone level. In all three patients, the chromosome origin, structure, and euchromatin content of the sSMCs were determined. In patient RS, only a neocentric r(2)(q35q36) was identified. It is a second neocentric sSMC(2) in the literature and the first marker chromosome derived from the terminal part of 2q. In the other two patients, two sSMCs were found, as M-FISH detected additional sSMCs that could not be characterized in G-banding analysis. In patient MK, each of four cell lines contained der(4)(:p11.1->.q12:) accompanied by a sSMC(18): r(18)(:p11.2->q11.1::p11.2->q11.1:), inv dup(18)(:p11.1->q11.1::q11.1->p11.1:), or der(18) (:p11.2->q11.1::q11.1->p11.1:). In patient NP, with clinical features of trisomy 8p, three sSMCs were characterized: r(8)(:p12->q11.1::q11.1->p21:) der(8) (:p11.22->q11.1::q11.1->p21::p21->p11.22:) and der(21)(:p11.1->q21.3:). The BAC array results confirmed the molecular cytogenetic results and refined the breakpoints to the single BAC clone resolution. However, the complex mosaic structure of the marker chromosomes derived from chromosomes 8 and 18 could only be identified by molecular cytogenetic methods. This study confirms the usefulness of multicolor FISH combined with whole-genome arrays for comprehensive analyses of marker chromosomes.

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2 Acta Physica Polonica A

1 Journal of Applied Genetics

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3 Pietrzak J.

2 Szyczewski A.

1 Bocian E.

1 But S.

1 Ca W. W.

1 Cheung S. W.

1 Elbanowski M.

1 Kosyakova N.

1 Kruczyński Z.

1 Liehr T.

1 Lis S.

1 Mazurczak T.

1 Mrasek K.

1 Möbius K.

1 Obersztyn E.

1 Stankiewicz P.

1 Weise A.

1 vo_ E. F.

Search results

Structure of Free Radical inγ-Irradiated 21-Hydroxyprogesterone (Deoxycorticosterone) Single Crystals. ESR/ENDOR and DFT Studies

EPR Study of Gadolinium(III) Complexes with Heteropolyanions: [Gd(SiW_{11}O_{39})_{2}]^{13-} and [GdP_{5}W_{30}O_{110}]^{12-}

Molecular cytogenetic characterization of eight small supernumerary marker chromosomes originating from chromosomes 2, 4, 8, 18, and 21 in three patients