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Rett syndrome (RTT) is a neurodevelopmental disorder associated with mutations in the X-linked gene encoding methyl-CpG-binding protein 2 (MeCP2) and consequent dysregulation of brain maturation. Patients suffer from a range of debilitating physical symptoms, however, behavioral and emotional symptoms also severely affect their quality of life. Here, we present previously unreported and clinically relevant affective dysfunction in the female heterozygous Mecp2tm1Tam mouse model of RTT (129sv and C57BL6 mixed background). The affective dysfunction and aberrant anxiety-related behavior of the Mecp2+ / - mice were found to be reversible with environmental enrichment (EE) from 4 weeks of age. The effect of exercise alone (via wheel running) was also explored, providing the first evidence that increased voluntary physical activity in an animal model of RTT is beneficial for some phenotypes. Mecp2+ / - mutants displayed elevated corticosterone despite decreased Crh expression, demonstrating hypothalamic-pituitary-adrenal axis dysregulation. EE of Mecp2+ / - mice normalized basal serum corticosterone and hippocampal BDNF protein levels. The enrichment-induced rescue appears independent of the transcriptional regulation of the MeCP2 targets Bdnf exon 4 and Crh. These findings provide new insight into the neurodevelopmental role of MeCP2 and pathogenesis of RTT, in particular the affective dysfunction. The positive outcomes of environmental stimulation and physical exercise have implications for the development of therapies targeting the affective symptoms, as well as behavioral and cognitive dimensions, of this devastating neurodevelopmental disorder.

Inositol-1,4,5-trisphosphate-3-kinase-A (ITPKA) has been considered as an actin bundling protein because its N-terminal actin binding domain (ABD) induces formation of linear actin bundles. Since in many cancer cell lines ITPKA is essential for formation of lamellipodia, which consist of cross-linked actin filaments, here we analyzed if full length-ITPKA may induce formation of more complex actin structures. Indeed, we found that incubation of F-actin with ITPKA resulted in formation of dense, branched actin networks. Based on our result that ITPKA does not exhibit an additional C-terminal ABD, we exclude that ITPKA cross-links actin filaments by simultaneous F-actin binding with two different ABDs. Instead, stimulated-emission-depletion-microscopy and measurement of InsP3Kinase activity give evidence that that N-terminal ABD-homodimers of ITPKA bind to F-actin while the monomeric C-termini insert between adjacent actin filaments. Thereby, they prevent formation of thick actin bundles but induce formation of thin branched actin structures. Interestingly, when embedded in this dense actin network, InsP3Kinase activity is doubled and the product of InsP3Kinase activity, Ins(1,3,4,5)P4, inhibits spontaneous actin polymerization which may reflect a local negative feedback regulation of InsP3Kinase activity. In conclusion, we demonstrate that not only the ABD of ITPKA modulates actin dynamics but reveal that the InsP3Kinase domain substantially contributes to this process. © 2015 Wiley Periodicals, Inc.

High energy lasers are a unique tool to create high pressure states above 10 Mbar at ns time scales, which allow to study material properties under these extreme conditions. These conditions are, for example, comparable with planetary cores, where material properties play an important role for the properties and evolution of a planet. The rapid compression allows also to study dynamic effects of phase transitions as compression times are comparable to relaxation times. We will present recent results of laser compression of iron reaching conditions of so called “super-Earth” cores. A description of the compression schemes as well as present and future diagnostics is presented. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

ReVIIO2(PO4) and (ReVII2O5)Sio2[Sit2O(PO4)6] were obtained from Re2O7 and P4O10 in sealed silica tubes (250 ≤ ϑ ≤ 400 °C). The crystal structures were solved and refined from X-ray single crystal data (ReVIIO2(PO4): C2/c, Z = 24, a = 14.403(1) A, b = 8.414(1) A, c = 20.647(3) A, β = 93.165(8)°, T = 123 K, 10352 ind. refl., 218 variables, 24 atoms in asymmetric unit, R1 = 0.041, wR2 = 0.106; (ReVII2O5)Sio2[Sit2O(PO4)6]: P, Z = 1, a = 7.8589(3) A, b = 7.8609(3) A, c = 10.8311(4) A, α = 85.312(2)°, β = 73.078(2)°, γ = 60.075(2)°, T = 298 K, 2551 ind. reflections, 174 variables, 22 atoms in asymmetric unit, R1 = 0.078, wR2 = 0.208). The complex crystal structure of ReO2(PO4) can be derived from the ReO3 structure type. The crystal structure of the silicophosphate consists of distorted [Re2O11] dioctahedra (1.69 A ≤ d(Re–O) ≤ 2.08 A), [SiIVO6] octahedra, and [Sit2O(PO4)6]12– heteropolyanions. In ReO2(PO4) monomeric perrhenyl ions (ReO2)3+ (∠(Ot,Re, Ot) ≈ 101.5°) are formed. The silicophosphate (Re2O5)Sio2[Sit2O(PO4)6] contains dinuclear (Re2O5)4+ cations. 31P-MAS-NMR studies on ReO2(PO4) are in accordance with three independent sites of phosphorus. The results of 31P- and 29Si-MAS-NMR studies on (Re2O5)Sio2[Sit2O(PO4)6] are in agreement with three crystallographically independent sites for phosphorus and two sites for silicon.

Interferon (IFN) regulatory factors (IRFs) are transcription factors with versatile functions in the regulation of innate and adaptive immune responses. In the current issue of the European Journal of Immunology, Steinhagen et al. [Eur. J. Immunol. 2013. 43: 1896–1906] investigate the regulation of IFN-β and IL-6 induction in human plasmacytoid DCs stimulated with CpG DNA. Using RNA interference studies, the authors identify critical roles for IRF5 and IRF8 as positive and negative regulators, respectively. In contrast, knockdown of IRF7 had no significant effect on IFN-β or IL-6 gene induction. In this Commentary, these findings are discussed in the context of the published literature and recent data regarding IRF5 and IRF8 as susceptibility genes for autoimmunity.

Objective To retrospectively analyse the effectiveness of bariatric surgery for hypothalamic obesity in patients with craniopharyngioma (CP). Patients Patients who developed morbid obesity after surgery for CP and who underwent laparoscopic gastric banding (LAGB), laparoscopic sleeve gastrectomy or gastric bypass were included (n = 9). Patients with common obesity who underwent bariatric surgery served as controls (LAGB n = 40, sleeve gastrectomy n = 49 and gastric bypass n = 54). Results CP was diagnosed during childhood or adolescence [median (range) 10 (1–21) years] and age at bariatric surgery was 17 [12–30] years. Six patients underwent gastric banding [median follow-up 5·5 years (range 1–9)], 4 had a sleeve gastrectomy [median follow-up 2 (0·4–4) years] and two patients had gastric bypass surgery (median follow-up 3 years). Three patients had more than one type of bariatric surgery. Different from controls, no weight loss was observed after LAGB or sleeve gastrectomy. The two patients who had gastric bypass surgery lost body weight comparable with controls. Conclusion With LAGB and sleeve gastrectomy, no significant loss of body weight was achieved in young adult patients with craniopharyngioma-associated morbid obesity.

Previous research on lesbian-led families rarely comments on specific mothering moments observed first hand by researchers. This article presents observations made with one such family in February of 2007, which followed up research I conducted throughout 2001–04 with this family and 29 other lesbian-led families. The vast majority of these informants are middle-class Euro-American lesbians living in the New York metropolitan area. In this article I detail particular mothering moments pertaining to the ways in which one couple educates and disciplines their children. Observations reveal an intentional rule-based parenting guided by expert opinion and focused on producing “highly intelligent,”“polite” children. I argue that raising “good children” is meaningful to lesbian couples in the United States as it indexes their own value as “good parents.” I suggest that my informants are nontraditional traditionalists as they parent and socialize their children in ways that cull components from cultural models from their own families of origin. These data offer a corrective to popular views of alternative family formations and practices as strictly countercultural. The family presented in the following microethnography consciously incorporates and reappropriates many traditional cultural values and models from the dominant heterosexual, middle-class, Euro-American culture. [lesbian-led families, U.S. parenting, childrearing, discipline, comothering, lesbian IVF]

An X-ray diffraction study has been carried out on single crystals of two symmetrical ureines (N,N′-diiopropylurea and the familiar N,N′-dicyclohexylurea) and one unsymmetrical ureine (N-tert.-butyl.N′-methylurea). The presence/absence of intermolecular H-bonds in the crystal state has been compared to the situation assessed in solution by 1H n.m.r. It was shown by i.r. absorption that soluble ureines may disrupt intermolecular (peptide)N—H- O=C(peptide) H-bonds in methylene chloride, a point of practical interest, particularly in solid-phase peptide synthesis.

AIM To investigate dye permeability of root dentine according to patients' age, root section and dye penetration time. METHODOLOGY A total of 96 extracted human single-rooted teeth, assigned to four age groups ( 60 years) were separated at the cemento-enamel junction and root canals were enlarged. The root surfaces were coated with cyanocrylate to prevent external dye penetration and centrifuged in distilled water to eliminate air. For dye penetration the root canals were filled with methylene blue 5%. After 1, 30 and 60 days eight roots per age group were cross-sectioned in 1 mm slices. Dye penetrated areas and the complete dentine areas were digitized and measured. Differences between groups were judged with anova and LSD, P < 0.05 or P < 0.01. RESULTS The root section, the patients' age and the penetration time influenced significantly the penetrated areas (P < 0.05). After 1 and 30 days significant differences could be found only in the apical root sections between all age groups (P < 0.05). Dye penetration areas systematically decreased with increasing age and also from coronal to apical (P < 0.01). CONCLUSIONS Age influenced dye penetration significantly. Dye penetration also depended on the location (coronal, middle and apical) within the root canal. These findings indicate that there may be a correlation between the tooth age and permeability of root dentine, which may influence the distribution and effectiveness of drugs used for root canal disinfection.

Rett syndrome, commonly associated with mutations of the methyl CpG-binding protein 2 (MECP2) gene, is characterised by an apparently normal early postnatal development followed by deterioration of acquired cognitive and motor coordination skills in early childhood. To evaluate whether environmental factors may influence the disease outcome of Rett syndrome, we tested the effect of environmental enrichment from 4 weeks of age on the behavioural competence of mutant mice harboring a Mecp2 tm1Tam-null allele. Our findings show that enrichment improves motor coordination in heterozygous Mecp2 +/− females but not Mecp2 −/y males. Standard-housed Mecp2 +/− mice had an initial motor coordination deficit on the accelerating rotarod, which improved with training then deteriorated in subsequent weeks. Enrichment resulted in a significant reduction in this coordination deficit in Mecp2 +/− mice, returning the performance to wild-type levels. Brain-derived neurotrophic factor (BDNF) protein levels were 75 and 85% of wild-type controls in standard-housed and environmentally enriched Mecp2 +/− cerebellum, respectively. Mecp2 −/y mice showed identical deficits of cerebellar BDNF (67% of wild-type controls) irrespective of their housing environment. Our findings demonstrate a positive impact of environmental enrichment in a Rett syndrome model; this impact may be dependent on the existence of one functional copy of Mecp2.

In this study, we investigated the immunomodulatory activity of coffee and Maillard reaction products on macrophages in vitro. Stimulation of macrophages with coffee, but not with raw coffee extract in PBS, led to a 13-fold increased nuclear NF-kappaB translocation. A Maillard reaction mixture (25 mM D-ribose/L-lysine, 30 min at 120 degrees C) increased NF-kappaB translocation 18-fold (in PBS) or six-fold (in medium). MRPs also induced a two-fold increased NF-kappaB translocation in untransfected human embryonic kidney (HEK) cells as well as in HEK cells stably transfected with the receptor for advanced glycation endproducts (RAGE), indicating that the effect was not RAGE mediated. On the other hand, catalase totally abolished coffee- and MRP-induced NF-kappaB translocation. Consequently, up to 366 microM hydrogen peroxide was measured in the coffee preparation and Maillard mixtures used for cell stimulation. Stimulation of macrophages with MRPs did not lead to significantly increased IL-6 or NO release. Thus, it can be concluded that coffee and MRPs induce NF-kappaB translocation in macrophages via the generation of hydrogen peroxide.

A monoclonal antibody raised against adenovirus E1A-associated cellular proteins recognized Nek9, a NimA-related protein kinase. Subcellular fractionation and immunofluorescence indicated that Nek9 was primarily cytoplasmic with a small portion located in the nucleus whereas E1A was primarily nuclear. Although co-immunoprecipitation experiments indicated that nuclear Nek9 interacted, directly or indirectly, with E1A, the major effect of E1A was to diminish the amount of Nek9 in the nucleus suggesting that E1A alters the subcellular distribution of Nek9 and that the interaction is transient. A Nek9 deletion mutant lacking a central RCC1-like domain interacted stably with E1A and accumulated in the nucleus in the presence of E1A, possibly representing an intermediate stage of the normally transient Nek9/E1A interaction. The interaction of Nek9 with E1A was dependent on the N-terminal sequences of E1A. Attempts to stably overexpress either Nek9 or the kinase-inactive mutant in various cell lines were unsuccessful; however, the presence of E1A allowed stable overexpression of both proteins. These results suggest that E1A disrupts a nuclear function of Nek9. J. Cell. Physiol. 212: 13–25, 2007. © 2007 Wiley-Liss, Inc.

The correlation between structural and magnetic properties of Au(111)/Co(0001)/Au(111) sandwiches with perpendicular magnetic anisotropy, grown by molecular beam epitaxy, has been studied in details. Thermal treatment in the range between room temperature and 300 °C at various stages of samples growth process as well as after its completion is applied as a factor modifying the structure of studied specimens. Annealing at 150 °C does not affect substantially either crystalline structure or perpendicular magnetic anisotropy. At 250 °C the RHEED pattern of Co layers reveals the loss of the lattice coherence with Au underlayer and the analysis of synchrotron radiation reflectometry leads to the conclusion that the continuity of Co layers is lost. Structural evolution upon thermal treatment is well correlated with changes of magnetic anisotropy studied by magnetooptical Kerr effect. After annealing at 250 °C magnetization switches from out-of-plane to in-plane orientation, which is explained in terms of interfacial and magnetoelastic contributions to the sample magnetic anisotropy. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Objectives Hemopoietic cytokines regulate hemopoietic cell functions via specific cell surface receptors. There is evidence to suggest, that those receptors (R) could play a role in leukemia with respect to cell differentiations and its regulation, prognosis, and pathobiology. Knowledge of individual cytokine receptor (CKR) profiles could provide new discoveries about CKR-supported therapeutic considerations. Methods We have studied the expression of CKR on mononuclear bone marrow (BM) cells of 89 patients with acute myeloid leukemia (AML) at first diagnosis, three patients at relapse or with persisting AML and eight healthy probands by fluorescence-activated cell sorting (FACS) analysis using directly fluorescein-conjugated antibodies: CD114 (hG-CSF-R), CD116 (hGM-CSF-R), CD117 (hSCF-R), CD123 (hIL-3-R), CD130 (gp130subunit), CD135 (hFL-R). A case was defined as positive, if more than 20% of the cells expressed the regarding CKR. Results All investigated CKR were more frequently expressed in AML-samples than in healthy BM-samples, except CD130, which was only expressed on 5-6% of AML-blasts in all and with only one healthy BM-sample being CD130(+). Within the French-American-British (FAB) types we observed a maturation- and lineage (granulocytic/monocytic)-committed expression profile. Monocytic subtypes (FAB-type M4/M5) showed significantly more GM-CSF-R(+) (P = 0.001) and FL-R(+) (P = 0.001) and significantly less stem cell factor-R (SCF-R(+)) (P = 0.02) cases. Highest proportions of G-CSF-R(+) blasts were observed in FAB-type M3. In undifferentiated leukemias (FAB-type M1, M2) high amounts of SCF-R(+), IL-3-R(+), and FL-R(+) blasts could be detected. FL-R was the only CKR, which was positive in FAB-type M0 (n = 2). No differences in CKR-expression were detected between primary (p) and secondary (s). Separating our patient cohorts in cytogenetic risk groups we could detect a significant higher proportion of G-CSF-R(+) blasts in the cytogenetic good risk group than in the bad risk group (P = 0.027), but G-CSF-R-expression did not correlate with remission-rate or relapse-free survival probability of the patients. For clinical evaluation only patients treated by the AML-CG-protocol, were included (n = 53). There were no differences of CKR-expression in the responder and non-responder group, however, significant lower relapse-free survival probabilities for patients with more than 85.5% FL-R(+) (P = 0.001) and more than 45.5% SCF-R(+) blasts were found (P = 0.02). Patients with more than 32.5% IL-3-R(+) cells also showed a tendency to a lower relapse-free survival probability (P = 0.26), whereas patients with more than 33% GM-CSF-R(+) (P = 0.06) and patients with more than 52% G-CSF-R(+) (P = 0.175) blasts tended to have a higher relapse-free survival probability. Conclusion We can conclude, that CKR-expression in AML is maturation- and lineage-committed and the proportions of especially early acting CKR have influence on relapse-free survival probability of AML-patients, independently of the karyotype. With respect to the individual CKR status the benefit of cytokines as priming agents, as agents to treat neutropenia or to influence the metabolism of chemotherapy can be discussed under new points of view.

Objectives: Interactions between hemopoietic cells and the stromal microenvironment or immunoreactive cells are mediated by specific cell surface receptors. The expression of those molecules may alter the adhesive qualities (mobility and homing) as well as immune response behavior of leukemic blasts. l-Selectin (CD62L) is suggested to play a role in the redistribution and homing of hemopoietic progenitor cells to the bone marrow (BM). Down-regulation of l-selectin is responsible for mobilization of blasts from the BM into the circulation and ligation of l-selectin stimulates proliferation of progenitor cells. This could have an influence on the process of leukemia. Method: We have studied the expression of l-selectin on mononuclear BM cells of 36 acute myeloid leukemia (AML) patients at first diagnosis by FACS analysis using a directly fluorescein isothiocyanate conjugated antibody (clone DRE G56). Results: On average the patients presented with 88% blasts in the BM. The expression tended to be higher in primary (p) AML compared with secondary (s) AML. l-Selectin was very heterogenously expressed in all FAB groups. Highest expression was found in cases with AML-M4 with four of nine cases presenting with an inv(16) karyotype. Separating our patient cohort in cytogenetic risk groups we could detect a significantly higher expression of l-selectin in cases with a ‘good risk’ karyotype and a very low expression in cases with a ‘bad risk’ karyotype (P = 0.037). Comparing patients who achieved remission after double induction therapy (responders) with patients who showed persisting disease (non-responders) we found a higher percentage of l-selectin+ cases or cells in the responder group than in the non-responder group, although the differences were not significant because of only five cases in the ‘non-responder’ group. Evaluating cut-off points greatest differences in relapse-free survival probabilities were found in patients who presented with ≥30%l-selectin+ BM cells compared with cases with

Complete removal of failed posterior resin composite fillings is time-expensive and involves the risk of removing sound tooth substance. In any case of failure within the composite material, intra-oral repair would be favourable. This in vitro study was conducted to examine the effect of different preparation and bonding modes on integrity of repaired restorations. Forty-eight direct Class II resin composite restorations (Syntac Classic/Tetric Ceram) were placed in extracted human third molars. The specimens were stored for 365 days and then replaced partially by removing the central part of the proximal box with all margins located in composite. The partial repairs were placed with the same materials after pre-treatment with a silicon carbide bur and Syntac Classic (n = 8). Preparation modes have been (i) box-only parallel, (ii) box-only with undercuts, (iii) box with undercuts and additional occlusal retention. The repairs were performed either with (i) Tetric Ceram or with (ii) Tetric Flow as thin lining covered with Tetric Ceram. Before and after thermomechanical loading (100 000 cycles of 50 N and 2500 cycles between +5 and +55 degrees C in an artificial mouth), marginal quality between aged and freshly applied composite was evaluated by SEM at x200 magnification and microleakage was observed by light microscopy at x50 magnification. Box-only preparations exhibited a better fatigue resistance than preparations with additional occlusal retention. This observation was independent from the presence of undercuts (P < 0.05). An intermediary layer of flowable resin composite tended to result in better marginal quality, however, not being statistically significant.

Summary. The survival of leukaemic blasts contributes to the pathological mechanism of acute promyelocytic leukaemia (APL). While treatment of APL using retinoic acid (RA) is a model of differentiation therapy, little is known about possible effects of this treatment on the Fas/FasL system. Investigation of APL cells from patients undergoing differentiation therapy with RA and of promyelocytic HL-60 and monoblastic U-937 cells cultured with RA revealed a reduction of surface expression of both Fas and its ligand. Accordingly, the sensitivity of the cells to anti-Fas-induced apoptosis decreased proportionally and the reduced expression of FasL resulted in a decreased ability of the leukaemic cells to induce apoptosis in T cells. Our findings demonstrate that there are significant changes in Fas and FasL expression during RA treatment of APL, which probably have consequences for the interaction between host immune and leukaemia cells, and thus may be involved in the beneficial effects of differentiation therapy.

ReVIIO2(PO4) (I) and (ReVII2O5)Si2 [Si2O(PO4)6] (II) are obtained from the reaction of Re2O7 and P4O10 in sealed silica tubes (temperature gradient 400 300 °C, 2 d).

The coordination of flavins to Lewis-acidic zinc(II)cyclen complexes, as a mimic for a metalloprotein binding site, changes their redox properties significantly. The coordination facilitates the electrochemical reduction of the flavin and stabilizes the flavinhydroquinone redox stage, so that a 600 mV more positive potential is necessary for reoxidation. Binding of flavin to the receptor molecule is not restricted to nonpolar solvents and works in methanol. Here, interception of the ECE mechanism of reduction is possible leading to a stabilization of the flavosemiquinone radical anion redox stage, which was proved by its characteristic UV absorption in spectroelectrochemistry. Although it has not yet been observed in flavoproteins, this study shows that flavin binding by coordination to a metal binding site is suitable for cofactor binding and modulation of its redox properties as well as other intermolecular interactions.

The reaction between 1,4,7,10-tetraazacyclododecane (cyclen) and partially protected derivatives and isocyanates gives macrocyclic ureas in good yields. Bridged biscyclens with aliphatic or aromatic spacers were obtained from the reaction between diisocyanates and partially protected cyclen. The substituted cyclen derivatives with one or two urea moieties coordinate zinc(II) and copper(II) ions to form stable mononuclear and dinuclear complexes. Potentiometric titration revealed that the urea substitution significantly changes the basicity of the remaining secondary amino groups of the macrocycle. In comparison with that of cyclen (1), which has two basic amino groups, the basicity of one amino group in 1,4,7,10-tetraazacyclododecane-1-carboxylic acid butylamide (6b) is reduced by 5 orders of magnitude. The binding affinity of cyclen (1), urea derivatives of cyclen, and metal complexes to double stranded DNA was measured under physiological conditions, using an ethidium bromide displacement assay. The binding affinities correlate with the positive charge of the protonated cyclic amines. Their metal complexes show even higher affinities, which presumably result from different binding motifs.

The glycoprotein CD36 functions as a thrombospondin receptor and is expressed on a variety of cell types, including platelets, monocyte/macrophages, and endothelial cells. In human skin, the presence of CD36 on keratinocytes was initially found in lesional areas of T-cell mediated inflammatory dermatoses. Controversy still exists on the interpretation of this expression as an inflammatory or differentiation-associated marker. So far, only limited data are available on CD36 expression in oral epithelia. The present immunohistochemical study was therefore performed to determine the presence of CD36 on keratinocytes of healthy and disease-affected epithelia of the oral cavity in 80 biopsy specimens. As results, we found an inflammation-independent strong expression of CD36 in oral epithelia with ortho- and parakeratinization, such as the oral side of the gingiva, the hard palate, and the back of the tongue. Non-keratinized epithelia such as the gingival pocket epithelium, the soft palate, the lip, the buccal mucosa, and the side of the tongue were CD36 negative. We therefore suggest that CD36 expression in keratinocytes from oral epithelia is an epithelial differentiation marker.

We report here a new synthetic route to highly-substituted tetraazamacrocycles. Raney nickel hydrogenation of macrocyclic phenylenediamine–acetylacetone condensation products gives cyclams in high yield with complexes all-cis stereoselectivity. The extensive C-substitution of the cyclam 2a changes its ligand properties markedly. The X-ray structure analyses of NiII, CuII, and ZnII complexes of 2a reveals a deviation of the metal ion coordination geometry from the usual square-planar arrangement. This may account for the differences in the redox properties of the NiII and CuII complexes of 2a leads to more positive oxidation and reduction potentials compared to the analogous unsubstituted cyclam complexes. While the binding constant between Zn(ClO4)2 and 2a is lower by a factor of 105 compared to cyclam, the subsequent binding of uridine to the zinc-cyclam complexes in methanol/water is slightly stronger in the case of 2a · Zn(ClO4)2].

The two-body and three-body wear of glass-ionomers (GIC), visible light cured glass-ionomers (VLC-GIC), and composites were compared. The wear simulations were performed for the two-body wear in an artificial mouth and for the three-body wear with the so-called ACTA machine. The tested materials were different conventional glass-ionomers, light cured glass-ionomers, composites, and amalgam. The wear rates of 8 specimens of each material for the two-body and 16 for the three-body wear test were compared. After 10(5) cycles with each testing device, the wear shapes were measured. All measurements were related to the wear rate of amalgam. For the two-body wear method, the worn materials were qualitatively judged by scanning electron microscopy. The two different wear testing methods lead to similar results with slight differences in ranking. Amalgam showed the lowest wear rates with both methods. Photac Fil, a newly developed VLC-GIC, showed dramatically lower wear resistance than composites and conventional GIC with both methods. Further investigations are necessary to identify the material-specific parameters influencing the wear behaviour of a material in relation to different wear testing methods.

The beta 1-integrins (VLA family) are cellular adhesion molecules (CAM) that play a major role in cell-cell and cell-matrix interactions. The expression pattern of CAM was studied in 5 clinically normal volunteers with healthy gingiva and in 18 patients with clinically different stages of periodontitis. In healthy human gingiva alpha 2, alpha 3 and alpha 6 integrin chains were found in a characteristic distribution, showing a broad continuous expression on the junctional and sulcular epithelium sites. The expression of these integrins was demonstrated primarily on the basal cell layers and in some cells of the stratum spinosum. Inflammatory stages of periodontitis revealed further upregulation of alpha 2, alpha 3 and alpha 6 integrins into the junctional and sulcular epithelial cells, which correlated with the stage of the periodontitis and the extent of the cellular infiltration. alpha 4 and alpha 6 were found to be the predominant beta 1 integrin chains on inflammatory cells. The amount of alpha 4 and alpha 6 positive infiltrative cells increased with the number of inflammatory cells. VCAM-1, the corresponding cell-cell ligand of VLA-4 (alpha 4) was present on the majority of subepithelial vessels in all stages of gingivitis and periodontitis. The alpha 5 subunit was expressed on both endothelium and gingival connective tissue cells. Samples from advanced periodontitis cases showed a higher number of alpha 5 positive mononuclear cells. In comparison to normal epidermis, human gingival epithelial cells express higher levels of integrins. This expression is further upregulated in advanced stages of periodontitis, indicating changes of the beta 1 integrin organization.

Information obtained owing to aquaintance with the course of the angular dependence of photoelectron intensity excited by the X-ray standing waves allows to determine, more explicitly, the state of crystal surface layer deformation. The aim of this work is to present a new measuring device constructed at the Institute of Physics of the Polish Academy of Sciences, especially the X-ray microcamera being simultaneously the proportional flowing counter used for measuring of photoelectron current emitted from the examined crystal. The angular dependence of the photoelectron current can be measured in coincidence with the angular running of rocking-curves. It is possible due to a computer program controlling the X-ray doble-crystal spectrometer, the microcamera and the electronic system for registration of the intensity of the diffracted beam as well the flowing counter. The scheme of the X-ray double-crystal spectrometer, the microcamera, and the electronic measuring system operation is given. There are also given the results of the introductory measurements carried out for the Si(111) implanted with the Au ions. The calculation of rocking-curve for non-disturbed crystal in the case of asymmetrically cut monochromator crystal was made. There was also estimated the range of depth from that the photoelectrons were emitted. Der Deformationszustand der Oberflachenschichten eines Einkristalls kann mit Hilfe der Winkelverteilung der Photoelektronen, die durch stehende Rontgenwellen angeregt wurden, bestimmt werden. Die Beschreibung der Mikrokamera mit einem rechnergesteuerten System ist Gegenstand dieser Arbeit. Dieses Gerat wurde im Institut fur Physik der Polnischen Akademie der Wissenschaften gebaut. Der Hauptteil dieses Gerates besteht aus der Mikrokamera, die gleichzeitig als Proportional-Fluszahler fungiert. In der Kamera befindet sich der zu untersuchende Kristall. Die Photoelektronen werden durch stehende Rontgenwellen im Kristall angeregt. Die Winkelabhangigkeit des Photoelektronenstromes wird gleichzeitig mit der Rocking-Kurve gemessen. Dazu dient ein Zweikristallspektrometer. Die Mikrokamera ist auf die Achse des zweiten Spektrometertisches aufgesetzt. Die Messungen werden mit Hilfe eines Computerprogramms ermoglicht, das das gesamte Gerat kontrolliert. Die Ergebnisse der erten Messungen an einem mit Au-Ionen implantierten Si Kristall werden diskutiert. Die experimentell gewonnene Rocking Kurve wird mit einr theoretisch ermittelten verglichen und der Grad der Austrittstiefe der Photoelektronen ermittelt.

Crystals of (H3O){[Cu(dien)]4[W(CN)8]} [W(CN)8]2·6.5H2O (dien: diethylenetriamine) are prepared by slow diffusion of aqueous solutions of [Cu(dien)(H2O)2]Cl2 and Cs3[W(CN)8] in an H-tube at room temperature (pH 5.5, 22% yield).

An X-ray diffraction analysts of two N-acyl derivatives of symmetrical dialkylureas, N-[Nα-(benzyloxycarbonyl)-L-valyl] -N, N′-diisopropylurea (1) and N-{Nα(tert-butyloxy)carbonyl -L-valyl}-N-N′-dicyclohexylurea (2), and one N-acyl derivative of an unsymmetrical N-N′-dialkylurea, N-[Nα-(benzyloxycarbonyl)-L-valyl] -N′-(tert-butyl)-N-ethylurea (3), has been performed. It was established that it is the least hindered O-acylisourca N-atom that attacks intramolecularly the carbonyl group of the Nα-protected amino acid activated by the unsymmetrical carbodiimide to form the major rearrangement product. The occurrence and nature of intra- and intermolecularly Hbonded forms of the N-acylureas in the crystal state were also assessed. It was also shown that soluble N-acylureas may compete with intermolecular (peptide)NH…OC(peptide) H-bonds in CH2Cl2.