Biochemical characterization of Neurospora crassa glycogenin (GNN), the self-glucosylating initiator of glycogen synthesis

Glycogenin acts in the initiation step of glycogen biosynthesis by catalyzing a self-glucosylation reaction. In a previous work [de Paula et al., Arch. Biochem. Biophys. 435 (2005) 112-124], we described the isolation of the cDNA gnn, which encodes the protein glycogenin (GNN) in Neurospora crassa. This work presents a set of biochemical and functional studies confirming the GNN role in glycogen biosynthesis. Kinetic experiments showed a very low GNN K-m (4.41 mu M) for the substrate UDP-glucose. Recombinant GNN was produced in Escherichia coli and analysis by mass spectroscopy identified a peptide containing an oligosaccharide chain attached to Tyr196 residue. Site-directed mutagenesis and functional complementation of a Saccharomyces cerevisiae mutant strain confirmed the participation of this residue in the GNN self-glucosylation and indicated the Tyr198 residue as an additional, although less active, glucosylation site. The physical interaction between GNN and glycogen synthase (GSN) was analyzed by the two-hybrid assay. While the entire GSN was required for full interaction, the C-terminus in GNN was more important. Furthermore, mutation in the GNN glucosylation sites did not impair the interaction with GSN. (c) 2005 Published by Elsevier B.V. on behalf of the Federation of European Biochemical Societies.

Self-assembly of organometallic Pd(II) complexes via CH3 center dot center dot center dot pi interactions: the first example of a cyclopalladated compound with herringbone stacking pattern

Two binuclear cyclometallated compounds [Pd(C-2,N-dmba)(mu-N-3)](2) (1) and [Pd-2(C-2,N-dmba)(2)(mu-N-3)(mu-Cl)] (2) (dmba = N,N-dimethylbenzylarnine) have been synthesized and characterized by elemental 3 analysis, IR and NMR spectroscopies and single crystal X-ray diffraction crystallography. The ability of CH3 groups to form C(sp(3))-H...pi hydrogen bonds with phenyl rings is responsible for the molecular self-assembly within the crystals of 1 and 2. Compound 1 crystallizes as one-dimensional supramolecular chains whereas the crystal packing of 2 consists of a herringbone of sandwiches composed by two inversely related [Pd-2(C-2,N-dmba)(2)(mu-N-3)(mu-Cl)] molecules. (c) 2007 Elsevier B.V. All rights reserved.

Durability of the bond strength of self-adhesive resin cements to human dentin

This study subjected two self-adhesive resin cements and two conventional resin cements to dry and aging conditions, to compare their microtensile bond strengths (MTBS) to dentin. Using four different luting systems (n = 10), 40 composite resin blocks (each 5x5x4 mm) were cemented to flat human crown dentin surfaces. The specimens were stored in water for 24 hours (37°C), at which point each specimen was sectioned along two axes to obtain beams that were divided randomly into two groups: dry samples, which were tested immediately, and samples that were subjected to accelerated aging conditions (12, 000 thermocycles followed by storage for 150 days). The μTBS results were affected significantly by the luting system used (P < 40001). Only the μTBS of Rely-X Unicem was reduced significantly after aging; the μTBS remained stable or increased for the other self-adhesive resin cement and the two conventional cements.

Evaluation of the Capillary Blood Glucose Self-monitoringProgram

OBJECTIVE: to evaluate the structure, process and results of the Capillary Blood Glucose Self-monitoring Program in a Brazilian city. METHOD: epidemiological, cross-sectional study. The methodological framework of Donabedian was used to construct indicators of structure, process and outcome. A random sample (n = 288) of users enrolled and 96 health professionals who worked in the program was studied. Two questionnaires were used that were constructed for this study, one for professionals and one for users, both containing data for the evaluation of structure, process and outcome. Anthropometric measures and laboratory results were collected by consulting the patients' health records. The analysis involved descriptive statistics. RESULTS: most of the professionals were not qualified to work in the program and were not knowledgeable about the set of criteria for patient registration. None of the patients received complete and correct orientations about the program and the percentage with skills to perform conducts autonomously was 10%. As regards the result indicators, 86.4% of the patients and 81.3% of the professionals evaluated the program positively. CONCLUSION: the evaluation indicators designed revealed that one of the main objectives of the program, self-care skills, has not been achieved.

Aggregates in the strength and gravity regime: Particles sizes in Saturn's rings

Particles in Saturn's main rings range in size from dust to kilometer-sized objects. Their size distribution is thought to be a result of competing accretion and fragmentation processes. While growth is naturally limited in tidal environments, frequent collisions among these objects may contribute to both accretion and fragmentation. As ring particles are primarily made of water ice attractive surface forces like adhesion could significantly influence these processes, finally determining the resulting size distribution. Here, we derive analytic expressions for the specific self-energy Q and related specific break-up energy Q(star) of aggregates. These expressions can be used for any aggregate type composed of monomeric constituents. We compare these expressions to numerical experiments where we create aggregates of various types including: regular packings like the face-centered cubic (fcc), Ballistic Particle Cluster Aggregates (BPCA), and modified BPCAs including e.g. different constituent size distributions. We show that accounting for attractive surface forces such as adhesion a simple approach is able to: (a) generally account for the size dependence of the specific break-up energy for fragmentation to occur reported in the literature, namely the division into "strength" and "gravity" regimes and (b) estimate the maximum aggregate size in a collisional ensemble to be on the order of a few tens of meters, consistent with the maximum particle size observed in Saturn's rings of about 10 m. (c) 2012 Elsevier B.V. All rights reserved.

Strength of the trilinear Higgs boson coupling in technicolor models

We discuss the strength of the trilinear Higgs boson coupling in technicolor (or composite) models in a model independent way. The coupling is determined as a function of a very general ansatz for the technicolor self-energy, and turns out to be equal or smaller than the one of the Standard Model Higgs boson depending on the dynamics of the theory. (c) 2006 Published by Elsevier B.V.

Kaon condensation and lambda-nucleon loop in the relativistic mean-field approach

The possibility of kaon condensation in high-density symmetric nuclear matter is investigated including both s- and p-wave kaon-baryon interactions within the relativistic mean-field (RMF) theory. Above a certain density, we have a collective (D) over bar (S) state carrying the same quantum numbers as the antikaon. The appearance of the (K) over bar (S) state is caused by the time component of the axial-vector interaction between kaons and baryons. It is shown that the system becomes unstable with respect to condensation of K-(K) over bar (S) pairs. We consider how the effective baryon masses affect the kaon self-energy coming from the time component of the axial-vector interaction. Also, the role of the spatial component of the axial-vector interaction on the possible existence of the collective kaonic states is discussed in connection with A-mixing effects in the ground state of high-density matter: Implications of K (K) over bar (S) condensation for high-energy heavy-ion collisions are briefly mentioned. (c) 2005 Elsevier B.V. All rights reserved.

Self-trapping of a binary Bose-Einstein condensate induced by interspecies interaction

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Photorefractive two-wave mixing phase coupling measurement in a self-stabilized recording regime

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Self-assembly of cyclometallated Pd(II) compounds directed by C-H center dot center dot center dot pi interactions: A structural evidence for metalloaromaticity in a cyclopalladated ring

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Nursing consultation applied to hypertensive clients: application of orem's self-care theory

O objetivo foi implantar a Consulta de Enfermagem para indivíduos hipertensos, utilizando-se a teoria do autocuidado de Orem e sistematizar a assistência de enfermagem. Foram entrevistados 56 pacientes, sendo 58,9% mulheres, 75% na faixa etária de 50 a 80 anos, 76,4% casados, 42,9% donas de casa, 47,2% aposentados e 67,3% com ensino fundamental completo. Utilizou-se instrumento estruturado abordando os requisitos de autocuidado universal, de desenvolvimento e de desvios de saúde. A análise dos dados possibilitou avaliar os requisitos de autocuidado alterados. No planejamento da assistência, as ações de apoio-educação foram prioridades. A teoria do autocuidado possibilitou identificar aspectos importantes para serem trabalhados pelo enfermeiro.

CORNWALL-NORTON MODEL IN THE STRONG-COUPLING REGIME

The Cornwall-Norton model is studied in the strong-coupling regime. It is shown that the fermionic self-energy at large momenta behaves as SIGMA(p) approximately (m2/p)ln(p/m). We verify that in the strong-coupling phase the dynamically generated masses of gauge and scalar bosons are of the same order, and the essential features of the model remain intact.

Localized mechanics of dentin self-etching adhesive system

The bond strength of composite resins (CRs) to dentin is influenced by the interfacial microstructure of the hybrid layer (HL) and the resin tags (TAG). The contemporary self-etching primer adhesive systems overcame the inconvenient of the etch-and-rinse protocol. Studies, however, have demonstrated that HL thickness and TAG length vary according to the wetting time and additional use of acid-etching prior to self-etching primers. This study investigated the localized stress distribution in the HL and the dentin/adhesive interface. Two HL thicknesses (3 or 6 mu m), two TAG lengths (13 or 17 mu m) and two loading conditions (perpendicular and oblique-25 degrees) were investigated by the finite element (FE) analysis. Five two-dimensional FE models (M) of a dentin specimen restored with CR (38 x 64 mu m) were constructed: M1 - no HL and no TAG; M2 - 3 mu m of HL and 13 mu m of TAG; M3 - 3 mu m of HL and 17 mu m of TAG; M4 - 6 mu m of HL and 13 mu m of TAG; and M5 - 6 mu m of HL and 17 mu m of TAG. Two distributed loadings (L) (20N) were applied on CR surface: L1 - perpendicular, and L2 - oblique (25 degrees). Fixed interfacial conditions were assigned on the border of the dentin specimen. Ansys 10.0 (Ansys (R), Houston, PA, USA) software was used to calculate the stress fields. The peak of von Mises (sigma(vM)) and maximum principal stress (sigma(max)) was higher in L2 than in L1. Microstructures (HL and TAG) had no effect on local stresses for L1. Decreasing HL decreased sigma(vM) and sigma(max) in all structures for L2, but the TAG length had influence only on the peributular dentin. The thickness of HL had more influence on the sigma(vM) and sigma(max) than TAG length. The peritubular dentin and its adjacent structures showed the highest sigma(vM) and sigma(max), mainly in the oblique loading.