35 resultados para Chain of value


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The treatment of sensorineural hearing loss is based on hearing aids, also known as individual sound amplification devices. The hearing aids purchased by the Brazilian Government, aiming at fulfilling public policies, are based on dedicated components, which bring about benefits, but also render them expensive and may impair repair services after manufacture`s warranty expires. Aim: to design digital behind-the-ear hearing aids built from standardized components coming from the very supply chain of these manufacturers. Study design: experimental. Materials and Methods: to identify the supply chain of these manufacturers, request samples and set up hearing aids in the laboratory. Results: The developed hearing aids did not show lesser electroacoustic characteristics when compared to those acquired by the Government, also being tested by the same reference international technical standard. Conclusion: It is possible to develop digital behind-the-ear hearing aids based on off-the-shelf components from hearing aid manufacturers` supply chain. Their advantages include low operational costs - for acquisition (with clear advantages for the Government) and service (advantage for the patient).

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Previous studies have shown that venoms of social wasps and bees exhibit strong anticoagulant activity. The present study describes the anticoagulant and fibrinogen-degrading pharmacological properties of the venom of Polybia occidentalis social wasp. The results demonstrated that this venom presented anticoagulant effect, inhibiting the coagulation at different steps of the clotting pathway (intrinsic, extrinsic and common pathway). The venom inhibited platelet aggregation and degraded plasma fibrinogen, possibly containing metal-dependent metalloproteases that specifically cleave the B beta-chain of fibrinogen. In conclusion, fibrinogenolytic and anticoagulant properties of this wasp venom find a potential application in drug development for the treatment of thrombotic disorders. For that, further studies should be carried out in order to identify and isolate the active compounds responsible for these effects. Blood Coagul Fibrinolysis 21: 653-659 (c) 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins.

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Objective: To determine whether basal levels of follicle-stimulating hormone (FSH) and anti-mullerian hormone (AMH), antral follicle count (AFC), and the numbers of dominant follicles, oocytes, and mature oocytes retrieved after ovarian stimulation differed between infertile women with endometriosis and healthy women undergoing assisted reproduction techniques (ART). Method: Of 77 consecutive ART candidates, 27 were infertile and had endometriosis. A male factor caused the infertility of the other 50, who acted as controls. Results: The AMH and AFC levels were similar in the 2 groups. The FSH levels were higher (8.28 mIU/ML [range, 5.25-24.1 mIU/ML] vs 5.91 mIU/mL [range, 2.47-18.7 mIU/ML]; P<0.01) in the study group. And the numbers of retrieved (n = 5 [range, 0-12] vs n = 9 [range, 0-27]; P<0.05) and mature oocytes (n = 4 [range, 0-11] vs n = 5 [range, 0-16]; P<0.05) were less in the study group. Conclusion: Because AMH levels were unchanged, endometriosis seems not to damage the primordial pool of follicles and oocytes, but to lessen the quality of the ovarian response to the hCG injection. Basal FSH levels may be of value in predicting ART success in women with the disease. (C) 2010 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

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One pair of reactants, Cu(hfac)(2) = M and the hinge-flexible radical ligand 5-(3-N-tert-butyl-N-aminoxylphenyl)pyrimidine (3PPN = L), yields a diverse set of five coordination complexes: a cyclic loop M(2)L(1) dimer; a 1:1 cocrystal between an M(2)L(2) loop and an ML(2) fragment; a ID chain of M(2)L(2) loops linked by M; two 2D M(3)L(2) networks of (M-L)(n) chains crosslinked by M with different repeat length pitches; a 3D M(3)L(2) network of M(2)L(2) loops cross-linking (M-L)(n)-type chains with connectivity different from those in the 2D networks. Most of the higher dimensional complexes exhibit reversible, temperature-dependent spin-state conversion of high-temperature paramagnetic states to lower magnetic moment states having antiferromagnetic exchange within Cu-ON bonds upon cooling, with accompanying bond contraction. The 3D complex also exhibited antiferromagnetic exchange between Cu(II) ions linked in chains through pyrimidine rings.

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In this paper we extend the results presented in (de Ponte, Mizrahi and Moussa 2007 Phys. Rev. A 76 032101) to treat quantitatively the effects of reservoirs at finite temperature in a bosonic dissipative network: a chain of coupled harmonic oscillators whatever its topology, i.e., whichever the way the oscillators are coupled together, the strength of their couplings and their natural frequencies. Starting with the case where distinct reservoirs are considered, each one coupled to a corresponding oscillator, we also analyze the case where a common reservoir is assigned to the whole network. Master equations are derived for both situations and both regimes of weak and strong coupling strengths between the network oscillators. Solutions of these master equations are presented through the normal ordered characteristic function. These solutions are shown to be significantly involved when temperature effects are considered, making difficult the analysis of collective decoherence and dispersion in dissipative bosonic networks. To circumvent these difficulties, we turn to the Wigner distribution function which enables us to present a technique to estimate the decoherence time of network states. Our technique proceeds by computing separately the effects of dispersion and the attenuation of the interference terms of the Wigner function. A detailed analysis of the dispersion mechanism is also presented through the evolution of the Wigner function. The interesting collective dispersion effects are discussed and applied to the analysis of decoherence of a class of network states. Finally, the entropy and the entanglement of a pure bipartite system are discussed.

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Thermal properties and degree of conversion (DC%) of two composite resins (microhybrid and nanocomposite) and two photo-activation methods (continuous and gradual) displayed by the light-emitting diode (LED) light-curing units (LCUs) were investigated in this study. Differential scanning calorimetry (DSC) thermal analysis technique was used to investigate the glass transition temperature (T(g)) and degradation temperature. The DC% was determined by Fourier transform infrared spectroscopy (FT-IR). The results showed that the microhybrid composite resin presented the highest T(g) and degradation temperature values, i.e., the best thermal stability. Gradual photo-activation methods showed higher or similar T(g) and degradation temperature values when compared to continuous method. The Elipar Freelight 2 (TM) LCU showed the lowest T(g) values. With respect to the DC%, the photo-activation method did not influence the final conversion of composite resins. However, Elipar Freelight 2 (TM) LCU and microhybrid resin showed the lowest DC% values. Thus, the presented results suggest that gradual method photo-activation with LED LCUs provides adequate degree of conversion without promoting changes in the polymer chain of composite resins. However, the thermal properties and final conversion of composite resins can be influenced by the kind of composite resin and LCU.

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The design of therapeutic compounds targeting transthyretin (TTR) is challenging due to the low specificity of interaction in the hormone binding site. Such feature is highlighted by the interactions of TTR with diclofenac, a compound with high affinity for TTR, in two dissimilar modes, as evidenced by crystal structure of the complex. We report here structural analysis of the interactions of TTR with two small molecules, 1-amino-5-naphthalene sulfonate (1,5-AmNS) and 1-anilino-8-naphthalene sulfonate (1,8-ANS). Crystal structure of TTR: 1,8-ANS complex reveals a peculiar interaction, through the stacking of the naphthalene ring between the side-chain of Lys15 and Leu17. The sulfonate moiety provides additional interaction with Lys15` and a water-mediated hydrogen bond with Thr119`. The uniqueness of this mode of ligand recognition is corroborated by the crystal structure of TTR in complex with the weak analogue 1,5-AmNS, the binding of which is driven mainly by hydrophobic partition and one electrostatic interaction between the sulfonate group and the Lys15. The ligand binding motif unraveled by 1,8-ANS may open new possibilities to treat TTR amyloid diseases by the elucidation of novel candidates for a more specific pharmacophoric pattern. (C) 2009 Published by Elsevier Ltd.

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Bothropasin is a 48 kDa hemorrhagic PIII snake venom metalloprotease (SVMP) isolated from Bothrops jararaca, containing disintegrin/cysteine-rich adhesive domains. Here we present the crystal structure of bothropasin complexed with the inhibitor POL647. The catalytic domain consists of a scaffold of two subdomains organized similarly to those described for other SVMPs, including the zinc and calcium-binding sites. The free cysteine residue Cys(189) is located within a hydrophobic core and it is not available for disulfide bonding or other interactions. There is no identifiable secondary structure for the disintegrin domain, but instead it is composed mostly of loops stabilized by seven disulfide bonds and by two calcium ions. The ECD region is in a loop and is structurally related to the RGD region of RGD disintegrins, which are derived from I`ll SVMPs. The ECD motif is stabilized by the Cys(117)_Cys(310) disulfide bond (between the disintegrin and cysteine-rich domains) and by one calcium ion. The side chain of Glu(276) of the ECD motif is exposed to solvent and free to make interactions. In bothropasin, the HVR (hyper-variable region) described for other Pill SVMPs in the cysteine-rich domain, presents a well-conserved sequence with respect to several other Pill members from different species. We propose that this subset be referred to as PIII-HCR (highly conserved region) SVMPs. The differences in the disintegrin-like, cysteine-rich or disintegrin-like cysteine-rich domains may be involved in selecting target binding, which in turn could generate substrate diversity or specificity for the catalytic domain. (C) 2008 Elsevier Ltd. All rights reserved.

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The motility of T cells depends on the dynamic spatial regulation of integrin-mediated adhesion and de-adhesion. Cathepsin X, a cysteine protease, has been shown to regulate T-cell migration by interaction with lymphocyte function associated antigen-1 (LFA-1). LFA-1 adhesion to the ICAM-1 is controlled by the association of actin-binding proteins with the cytoplasmic tail of the beta(2) chain of LFA-1. Cleavage by cathepsin X of the amino acid residues S(769), E(768) and A(767) from the C-terminal of the beta(2) cytoplasmic tail of LFA-1 is shown to promote binding of the actin-binding protein alpha-actinin-1. Furthermore, cathepsin X overexpression reduced LFA-1 clustering and induced an intermediate affinity LFA-1 conformation that is known to associate with a-actinin-1. increased levels of intermediate affinity LFA-1 resulted in augmented cell spreading due to reduced attachment of T cells to the ICAM-1-coated surface. Gradual cleavage of LFA-1 by cathepsin X enables the transition between intermediate and high affinity LFA-1, an event that is crucial for effective T-cell migration.

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We explicitly construct a stationary coupling attaining Ornstein`s (d) over bar -distance between ordered pairs of binary chains of infinite order. Our main tool is a representation of the transition probabilities of the coupled bivariate chain of infinite order as a countable mixture of Markov transition probabilities of increasing order. Under suitable conditions on the loss of memory of the chains, this representation implies that the coupled chain can be represented as a concatenation of i.i.d. sequences of bivariate finite random strings of symbols. The perfect simulation algorithm is based on the fact that we can identify the first regeneration point to the left of the origin almost surely.

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Dental roots that have been exposed to the oral cavity and periodontal pocket environment present superficial changes, which can prevent connective tissue reattachment. Demineralizing agents have been used as an adjunct to the periodontal treatment aiming at restoring the biocompatibility of roots. OBJECTIVE: This study compared four commonly used demineralizing agents for their capacity of removing smear layer and opening dentin tubules. METHODS: Fifty fragments of human dental roots previously exposed to periodontal disease were scaled and randomly divided into the following groups of treatment: 1) CA: demineralization with citric acid for 3 min; 2) TC-HCl: demineralization with tetracycline-HCl for 3 min; 3) EDTA: demineralization with EDTA for 3 min; 4) PA: demineralization with 37% phosphoric acid for 3 min; 5) Control: rubbing of saline solution for 3 min. Scanning electron microscopy was used to check for the presence of residual smear layer and for measuring the number and area of exposed dentin tubules. RESULTS: Smear layer was present in 100% of the specimens from the groups PA and control; in 80% from EDTA group; in 33.3% from TC-HCl group and 0% from CA group. The mean numbers of exposed dentin tubules in a standardized area were: TC-HCl=43.8±25.2; CA=39.3±37; PA=12.1±16.3; EDTA=4.4±7.5 and Control=2.3±5.7. The comparison showed significant differences between the following pairs of groups: TC-HCl and Control; TC-HCl and EDTA; CA and Control; and CA and EDTA. The mean percentages of area occupied by exposed dentin tubules were: CA=0.12±0.17%; TC-HCl=0.08±0.06%; PA=0.03±0.05%; EDTA=0.01±0.01% and Control=0±0%. The CA group differed significantly from the others except for the TC-HCl group. CONCLUSION: There was a decreasing ability for smear layer removal and dentin tubule widening as follows: AC>TC-HCl>PA>EDTA. This information can be of value as an extra parameter for choosing one of them for root conditioning.

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Problematiza-se a afirmação de que não são válidas as estimativas sobre as condições de saúde bucal da população brasileira geradas pelo SB Brasil 2003. Criticam-se os elementos que pretendem sustentar esse ponto de vista com base apenas em conceitos estatísticos, sem prova empírica. Identificam-se reduções decorrentes da abordagem epistemocêntrica que recusa peremptoriamente outras formas de conhecimento e não reconhece o caráter multidisciplinar da epidemiologia. Reconstituem-se informações sobre a realização do levantamento e seu impacto na produção de conhecimento. Faz-se uma analogia entre ciência e arte, argumentando-se que, nas imagens obtidas por ambas, os saberes gerados a partir do objeto cognoscível assumem feições variadas e, portanto, o reconhecimento de sua validade requer amplo domínio do objeto e operações com adequados critérios de valor. Conclui-se pela cientificidade, validade e relevância da produção acadêmica desenvolvida a partir da base de dados do levantamento SB Brasil 2003.

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São raros os momentos, na história das políticas de preservação do patrimônio no Brasil, em que se vê a dimensão de um conflito - gerado pela atribuição de valores a um bem cultural - alcançar repercussão significativa, mobilizando diversos agentes. O caso do edifício Luciano Costa, no Recife, é um exemplo dessa natureza. Neste artigo, procuramos apresentar -a partir da interpretação de uma trama complexa de discursos e ações - a polêmica preservacionista em torno desse edifício, um exemplar arquitetônico singular, por ter simultaneamente duas fachadas, uma eclética e uma modernista. Em grande parte inéditos, os documentos técnico-administrativos da 5ª Superintendência Regional e do Departamento de Documentação do Iphan, assim como aqueles da fundação do Patrimônio Histórico e Artístico de Pernambuco (fundarpe), da Diretoria de Projetos Especiais da Empresa de Urbanização do Recife (URb-Recife) e do Ministério Público de Pernambuco foram as fontes primárias privilegiadas.

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Interleukin-22 (IL-22) is a class 2 cytokine whose primary structure is similar to that of interleukin 10 (IL-10) and interferon-gamma (IFN-gamma). IL-22 induction during acute phase immune response indicates its involvement in mechanisms of inflammation. Structurally different from IL-10 and a number of other members of IL-10 family, which form intertwined inseparable V-shaped dimers of two identical polypeptide chains, a single polypeptide chain of IL-22 folds on itself in a relatively globular structure. Here we present evidence, based on native gel electrophoresis, glutaraldehyde cross-linking, dynamic light scattering, and small angle x-ray scattering experiments, that human IL-22 forms dimers and tetramers in solution under protein concentrations assessable by these experiments. Unexpectedly, low-resolution molecular shape of IL-22 dimers is strikingly similar to that of IL-10 and other intertwined cytokine dimeric forms. Furthermore, we determine an ab initio molecular shape of the IL-22/IL-22R1 complex which reveals the V-shaped IL-22 dimer interacting with two cognate IL-22R1 molecules. Based on this collective evidence, we argue that dimerization might be a common mechanism of all class 2 cytokines for the molecular recognition with their respective membrane receptor. We also speculate that the IL-22 tetramer formation could represent a way to store the cytokine in nonactive form at high concentrations that could be readily converted into functionally active monomers and dimers upon interaction with the cognate cellular receptors.

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In the Peruvian Amazon, the white-lipped peccary (Tayassu pecan) is a desirable game species and is important for the local rural economy. Blood samples from 101 white-lipped peccaries from Peru were collected from 3 different conservation areas located in the municipalities of Manu and Tambopata, southeastern region of the Peruvian Amazon. Antibodies were assayed using the modified agglutination test (MAT, cut of value of 25). Antibodies to Toxoplasma gondii were found in 89.1% (90 of 101) of animals, with titers of 1:25 in 9, 1:50 in 25, 1:100 in 20, 1:200 in 14, 1:400 in 12, 1:800 in 9, and 1:3,200 in 1; 87.7% and 89.2% of males and females, respectively, tested positively, and no association (P >= 0.05) with gender and occurrence of antibodies was observed.