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The salts of 1,4-diazabicyclo[2.2.2]octane (DABCO) and bis(trifluoromethylsulfonyl)amine (in 1 : 1 and 1 : 2 stoichiometry, 1and 2, respectively) were investigated by DSC, TGA, PXRD and single crystal X-ray diffraction. Thermal analysis of the two compounds revealed reversible phase transitions, indicating enantiotropic relationships between all the polymorphs. Compound 1can exist as a room-temperature form 1Land as a high-temperature modification 1H. By contrast, 2forms a low- (2L), an intermediate- (2I) and a high-temperature (2H) polymorph. The structures of 1Land 2Lwere determined by single crystal X-ray crystallography. N–HO bonded cations of 1Lare arranged in a staggered fashion and form infinite chains. The crystal contains two sets of symmetry related H-bonded chains, which are in an inclined orientation relative to one another. In the structure of 2L, the cation is N–HO bonded to two neighbouring triflimide anions. The discrete H-bonded structure fragments resulting from these interactions assemble to a layer structure. The structure determination of the high-temperature forms 1Hand 2Hfrom PXRD data was negatively affected by a high degree of disorder of the triflimide anions. All N–HO bonded DABCO chains in 1Hadopt a parallel orientation, which is in contrast to the inclined orientation found in 1L. [ABSTRACT FROM AUTHOR]

Tissue chromium levels of subjects with diabetes are lower than those of normal control subjects, and a correlation exists between low circulating levels of chromium and the incidence of type-2 diabetes. Chromium is an essential mineral that appears to have a beneficial role in the regulation of insulin action, metabolic syndrome, and cardiovascular disease. There is growing evidence that chromium may facilitate insulin signalling and chromium supplementation therefore may improve systemic insulin sensitivity. Controversy still exists as to the need for chromium supplementation. However, supplementation with chromium has been shown to reduce insulin resistance and to help reduce the risk of cardiovascular disease and type-2 diabetes. Since chromium supplementation is a safe treatment, further research is necessary to resolve the confounding data. [ABSTRACT FROM AUTHOR]

The novel metal complexes bis(3-acetyl-2,4-pentanedionato-O2,O3)palladium(ii), Pd[C7O3H9]2, and bis(3-acetyl-2,4-pentanedionato-O2,O3)magnesium(ii), Mg[C7O3H9]2, have been synthesized. They are comprehensively characterized by a number of complementary methods. Spectroscopic data of the molecules in solution have been obtained by means of 1H- and 13C NMR. X-Ray powder diffractograms, IR- and micro-Raman spectra have been obtained from polycrystalline material and are discussed in detail. The crystal structures have been determined from laboratory X-ray powder diffraction data and subsequently refined with the Rietveld technique. In both complexes, the central metal cation is coordinated by two chelating ligands, forming a square-planar coordination. The crystal structure of the palladium(ii) complex is comprised of isolated molecules the stability and catalytic capabilities of which make the compound a promising candidate as a metal–organic frameworks (MOF) interlinker. In contrast, the magnesium(ii) complex undergoes supplementary intermolecular ligation to complete an octahedral coordination of the Mg(ii), resulting in an extended layer structure. Line-shifts and -splittings in the Raman spectra are identified, from which the structural features of further complexes could be identified. [ABSTRACT FROM AUTHOR]

Infants born to women with type 1 diabetes (T1D) are at increased risk of neonatal morbidity. Intrapartum monitoring is therefore essential to minimize complications. We analyzed APGAR scores after 1 and 5 min. in BABYDIAB offspring from mothers with T1D (n= 1047) compared to offspring from nondiabetic mothers whose partners had T1D (n= 592). Sectio rates in mothers with T1D were increased more than two-fold (48.1%) compared to mothers w/o T1D (21.4%, p<0.0001). 16 of 927 offspring (1.7%) suffered from initial asphyxia as defined by an APGAR (1) < 7. Neonates from mothers with T1D had lower mean APGAR scores (1′: 9.18 and 5′: 9.59) compared to offspring from non-diabetic mothers (1′: 9.58 and 5′: 9.87, p<0.0001). Translated into clinical practice, that was a lower rate of maximally good APGAR scoring of 10 (47%) in children from mothers with T1D compared with offspring from non-diabetic mothers (71.8%, p<0.0001) while rates of early asphyxia were not different (1.9% vs 1.7%). Since mean APGAR scores were decreased in offspring delivered by sectio compared with neonates born spontaneously (1′: 9.19 vs 9.49, 5′:9.61 vs 9.78, p<0.0001), APGAR scores by maternal diabetes status were controlled for the mode of delivery. Again, rates of low APGAR 1′ scores were higher and rates of maximally good scores lower both in offspring from diabetic mothers delivered by sectio and in children born spontaneously compared to offspring from non-diabetic mothers (p<0.034, p<0.0001 ). HbA1c levels at delivery were slightly higher in mothers who gave birth by sectio (5.86%) compared to mothers who delivered spontaneously (5.69% p<0.035). Mean APGAR1′ scores were also lower in offspring from mothers with elevated HbA1c levels (mean APGAR1′ (HbA1c-subgroups) 9.51 (>8%) vs 9.42(7-8%), vs 9.44(6-7%) vs 9.25 (5-6%), p<0.007, Kruskal-Wallis). In conclusion, offspring of mothers with well controlled T1D may not be at risk of severely compromised vitality at birth, however, they less often score maximum points on the APGAR scale compared to offspring from non-diabetic mothers. [ABSTRACT FROM AUTHOR]

The N-heterocyclic carbene (NHC) precursors 1-[(E)-2-butenyl]-3-(4-ferrocenylphenyl)imidazolium bromide (2) and 1-[(E)-2-butenyl]-3-(4-ferrocenylphenyl)imidazolium tetrafluoroborate (3) were derived from 1-(4-ferrocenylphenyl)imidazole. Ferrocenyl complex 3 reacts with Ag2O and chloro(dimethylsulfide)gold(i) in the presence of tetraethylammonium chloride to produce the mixed metal species bis{1-[(E)-2-butenyl]-3-(4-ferrocenylphenyl)-2H-imidazol-2-ylidene}gold(i) tetrafluoroborate (4). Single crystal X-ray structure analyses of 1, 3 and 4 indicate that the NCHN-hydrogen in 3 is hydrogen bonded to the BF4− anion [C(H1)⋯F, 3.265(4) Å], as is also reflected in the position of its 1H NMR chemical shift. Cytotoxicity studies show that complex 4 is selective for cancer cells and active against the tumour cell lines Jurkat and MCF 7. [ABSTRACT FROM AUTHOR]

Induced pluripotent stem (iPS) cells have been generated from bone marrow (BM) hematopoietic progenitor cells by ectopic expression of Sox-2, Oct-4, and Klf-4 with the hope that they may differentiate more efficiently than embryonic stem (ES) cells in vitro into hematopoietic cell lineages because of their epigenetic memory. An in vitro culture system has been standardized to allow a quantitative assessment of the capacities of different ES, BM-derived iPS, and fibroblast-derived iPS cell lines developing to erythroid, myeloid, and lymphoid cell lineages. Surprisingly, the efficiency to differentiate BM-derived iPS cells to hematopoietic cells in vitro is severely reduced compared with ES cells and fibroblast-derived iPS cells. Undifferentiated as well as differentiated stages of the BM-derived iPS lines express elevated mRNA levels of the transcription factors Sox-2, Oct-4, and Klf-4 with which the iPS cells have been transduced. Overexpression of the transcription factors inhibits development of Flk-1+mesodermal to CD45+hematopoietic progenitors. The overexpression of Sox-2 appears to be inversely related to hematogenic potency. These results suggest that iPS cell generation with the aim of developing hematopoietic cells should be controlled and selected for low levels of transduced Sox-2, Oct-4, and Kfl-4 expression. [ABSTRACT FROM AUTHOR]

The novel analogue of the parent Zr(acac)4 complex, tetrakis(3-acetyl-2,4-pentanedionato)zirconium(IV), Zr[C7O3H9]4, has been synthesized straightforwardly by a salt-free methodology and was characterized by a number of complementary methods (1H NMR, 13C NMR, IR, and bulk density). From polycrystalline material, X-ray powder diffractograms and micro-Raman spectra were obtained and are discussed in detail. The crystal structure was determined from laboratory X-ray powder diffraction data by simulated annealing and subsequently refined with the Rietveld technique. The compound is monoclinic with space group P2/c. Zr, residing on a crystallographic 2-fold rotation axis, is coordinated by the four chelating ligands forming a square-antiprismatic coordination polyhedron. Differences and similarities to zirconium(IV)acetylacetonate, Zr[C5O2H7]4, and other similar complexes are discussed, addressing the conformational rigidity of this symmetrically substituted homoleptic acac complex. [ABSTRACT FROM AUTHOR]