Further evidence for the reliance of catalysis by rabbit muscle pyruvate kinase upon isomerization of the ternary complex between enzyme and products

Isothermal calorimetry has been used to examine the effect of thermodynamic non-ideality on the kinetics of catalysis by rabbit muscle pyruvate kinase as the result of molecular crowding by inert cosolutes. The investigation, designed to detect substrate-mediated isomerization of pyruvate kinase, has revealed a 15% enhancement of maximal velocity by supplementation of reaction mixtures with 0.1 M proline, glycine or sorbitol. This effect of thermodynamic non-ideality implicates the existence of a substrate-induced conformational change that is governed by a minor volume decrease and a very small isomerization constant; and hence, substantiates earlier inferences that the rate-determining step in pyruvate kinase kinetics is isomerization of the ternary enzyme product complex rather than the release of products. (C) 2003 Elsevier Science B.V. All rights reserved.

Quality of care of patients hospitalized with congestive heart failure

Background: Congestive heart failure (CHF) is an increasingly prevalent poor-prognosis condition for which effective interventions are available. It is -therefore important to determine the extent to which patients with CHF receive appropriate care in Australian hospitals and identify ways for improving suboptimal care, if it exists. Aim: To evaluate the quality of in-hospital acute care of patients with CHF using explicit quality indicators based on published guidelines. Methods: A retrospective case note review was -performed, involving 216 patients admitted to three teaching hospitals in Brisbane, Queensland, Australia, between October 2000 and April 2001. Outcome measures were process-of-care quality -indicators calculated as proportions of all, or strongly -eligible (ideal), patients who received -specific interventions. Results: Assessment of underlying causes and acute precipitating factors was undertaken in 86% and 76% of patients, respectively, and objective evaluation of left ventricular function was performed in 62% of patients. Prophylaxis for deep venous thrombosis (DVT) was used in only 29% of ideal patients. Proportions of ideal patients receiving pharmacological treatments at discharge were: (i) angiotensin--converting enzyme inhibitors (ACEi) (82%), (ii) target doses of ACEi (61%), (iii) alternative vasodilators in patients ineligible for ACEi (20%), (iv) beta-blockers (40%) and (v) warfarin (46%). Conclusions: Opportunities exist for improving quality of in-hospital care of patients with CHF, -particularly for optimal prescribing of: (i) DVT prophylaxis, (ii) ACEi, (iii) second-line vasodilators, (iv) beta-blockers and (v) warfarin. More research is needed to identify methods for improving quality of in-hospital care.

Epitope-blocking enzyme-linked immunosorbent assays for the detection of serum antibodies to West Nile virus in multiple avian species

We report the development of epitope-blocking enzyme-linked immunosorbent assays (ELISAs) for the rapid detection of serum antibodies to West Nile virus (WNV) in taxonomically diverse North American avian species. A panel of flavivirus-specific monoclonal antibodies (MAbs) was tested in blocking assays with serum samples from WNV-infected chickens and crows. Selected MAbs were further tested against serum samples from birds that represented 16 species and 10 families. Serum samples were collected from birds infected with WW or Saint Louis encephalitis virus (SLEV) and from noninfected control birds. Serum samples from SLEV-infected birds were included in these experiments because WNV and SLEV are closely related antigenically, are maintained in similar transmission cycles, and have overlapping geographic distributions. The ELISA that utilized MAb 3.11126 potentially discriminated between WW and SLEV infections, as all serum samples from WNV-infected birds and none from SLEV-infected birds were positive in this assay. Assays with MAbs 2132 and 6B6C-1 readily detected serum antibodies in all birds infected with WNV and SLEV, respectively, and in most birds infected with the other virus. Two other MAbs partially discriminated between infections with these two viruses. Serum samples from most WNV-infected birds but no SLEV-infected birds were positive with MAb 3.676, while almost all serum samples from SLEV-infected birds but few from WNV-infected birds were positive with MAb 6B5A-5. The blocking assays reported here provide a rapid, reliable, and inexpensive diagnostic and surveillance technique to monitor WNV activity in multiple avian species.

Epitope-blocking enzyme-linked immunosorbent assays for detection of West Nile virus antibodies in domestic mammals

We evaluated the ability of epitope-blocking enzyme-linked immunosorbent assays (ELISAs) to detect West Nile virus (WNV) antibodies in domestic mammals. Sera were collected from experimentally infected horses, cats, and pigs at regular intervals and screened in ELISAs and plaque reduction neutralization tests. The diagnostic efficacies of these techniques were similar.

Characterisation of grafted supports used for solid-phase synthesis

A series of 'pellicular' type supports were fabricated by direct gamma-radiation-mediated graft polymerisation of styrene onto polypropylene, followed by aminomethylation. Raman spectroscopy was used for measuring the level of penetration of polystyrene graft into polypropylene, and other structural features such as density of graft and depth of functionalisation. The kinetics of the coupling of fluorenylmethylcarbamate (Fmoc)-labelled amino acids, to the aminomethylated polystyrene grafts have been measured by UV absorption followed cleavage of the Fmoc chromophore. The Raman spectroscopy results showed that for this series of experiments the calculated rate coefficient for coupling of Fmoc-labelled amino acids was primarily dependent on graft thickness, but was also influenced by the proportion of polystyrene graft to polypropylene. In general, it was also shown that with increasing loading capacity of support the calculated rate coefficient for amino-acid coupling decreased correspondingly. In addition, a support that had both a high rate coefficient and a high loading capacity was prepared from polypropylene base material with a co-continuous porous structure (high surface area). (C) 2003 Society of Chemical Industry.

Amylases in enzyme detergents and their effects on a simulated long-life dairy dessert

Enzyme detergents used in the food industry contain proteinase as the major enzyme but amylase may be present, either by design or inadvertently. Three commercial enzyme detergents and 3 enzyme preparations used in detergents were assayed for alpha-amylase activity by the Ceralpha method using the Megazyme kits. The amylase activities of the detergents varied from 3.2x 10(-6) to 32x 10(-6) mumoles ml(-1) h(-1) while the enzyme preparations had much higher activities ranging from 0.05 to 8.06 mumoles ml(-1) h(-1). When added aseptically to a simulated dairy dessert (2% starch solution) and stored for 42 days, the enzyme detergents caused an increase in viscosity; enzyme preparations at low concentrations caused an initial increase in viscosity followed by a decrease; and enzyme preparations at high concentrations caused an immediate decrease in viscosity. The increase in viscosity corresponded to formation of a distinct network of starch granules while the decrease in viscosity was characterised by a marked decrease in size of the granules and little or no network of granules. Decreases in viscosity corresponded to increases in reducing sugars but samples which increased in viscosity showed no measurable reducing sugars. The amylase activity in all sources was destroyed by heating at 75degreesC for 15 min at pH 1.8.

Inclusão ideal e inclusão real : estudo de caso com professoras de crianças surdas em uma escola regular de João Pessoa – PB

O presente estudo tem como objetivo analisar as condições de inclusão educacional de crianças surdas em uma escola regular, a partir dos relatos de professoras que vivenciam essa prática. Para coletar informações a esse respeito, foram realizadas junto às participantes entrevistas de caráter semi-estruturado. No tratamento a esses dados foram descritas as condições de inclusão existentes na escola (campo de pesquisa), como também os significados elaborados pelas participantes acerca do aluno surdo e da inclusão do mesmo na escola regular. Os dados foram coletados em uma amostra de cinco professoras de classes regulares que possuem alunos surdos. Esses dados foram submetidos a uma análise de conteúdo manual dos mesmos no modelo de Bardin (2002). Os resultados apontam para uma visão predominantemente negativa das condições de inclusão oferecidas pela escola, consideradas como inadequadas. Isto é agravado pela insuficiência em termos de capacitação dos professores para o trabalho inclusivo. Observa-se, pois, do ponto de vista das participantes, a existência de uma discrepância entre os modelos legal e real de inclusão das crianças surdas em escola regular, que se manifesta em diversos aspectos da prática pedagógica nesse contexto.

O cinema do SPN/SNI – o ideal de Ferro, a realidade de chumbo

In Europe, the first half of the twentieth century was characterize by the rise of authoritarian regimes that used cinema as a propaganda tool for the prosecution and consolidation of political power. Indeed, film conveyed images, symbols, myths to an extent and strength that no other media had. In Portugal, the 1930 and 1940’s represent one of the most significant phases, either because of the introduction/strengthening of the technology of sound cinema, whether by the action of the Secretariado Nacional de Propaganda, the propaganda instrument of Estado Novo. Among the multitude of ways that this organization resorted to spread the political message of Estado Novo, cinema in particular aroused the attention of its director, António Ferro, as a preferred mean of communication with the masses. This communication seeks to examine the role played by António Ferro in the national film scene. It intends to determine the nature and direction of his cinematographic vision, i.e., his ethical and aesthetic assumptions, firstly, and secondly, its political action towards the portuguese film industry, as director of the SPN / SNI, under the tutelage of Oliveira Salazar.

O cinema do SPN/SNI – o ideal de Ferro, a realidade de chumbo

Em Portugal, as décadas de 1930 e 1940 constituem um período importante, quer pela introdução/consolidação tecnológica do cinema sonoro, quer pela acção do Secretariado da Propaganda Nacional. Dentre a multitude de meios de que este organismo se serviu para a difusão da mensagem política do regime do Estado Novo, o cinema desperta em particular a atenção do seu director, António Ferro, como meio privilegiado de comunicação com as massas. Neste artigo procura-se averiguar o papel desempenhado por António Ferro no panorama cinematográfico nacional, a nível da sua acção política sobre o cinema português.

Optimal location of supports in beam structures using genetic algorithms

Real structures can be thought as an assembly of components, as for instances plates, shells and beams. This later type of component is very commonly found in structures like frames which can involve a significant degree of complexity or as a reinforcement element of plates or shells. To obtain the desired mechanical behavior of these components or to improve their operating conditions when rehabilitating structures, one of the eventual parameters to consider for that purpose, when possible, is the location of the supports. In the present work, a beam-type structure is considered, and for a set of cases concerning different number and types of supports, as well as different load cases, the authors optimize the location of the supports in order to obtain minimum values of the maximum transverse deflection. The optimization processes are carried out using genetic algorithms. The results obtained, clearly show a good performance of the approach proposed. © 2014 IEEE.

Enzyme linked immunosorbent assay: determination of anti-adenovirus antibodies in an infant population

In order to define an accurate assay for anti-adenovirus antibody detection, a recently developed ELISA was compared with IFA and CF. On 58 sera, the ELISA was more sensitive than both CF and IFA, which showed relative sensitivities of 63% and 94%, respectively. It was not possible to determine the exact specificity of the tests because of the lack of a gold standard. Furthermore, the ELISA was used to define the prevalence of adenovirus antibodies in 116 infants between 1 and 24 months old (mean 7.28). The data showed that maternal antibodies waned by the age of 5 to 6 months and that more than 80% of the children had been infected by adenoviruses by the age of 10 months.

Evaluation of enzyme-linked immunosorbent and alternative assays for detection of HIV antibodies using panels of Brasilian sera

Sera from 472 Brazilian subjects, confirmed to be either positive or negative for HIV antibodies and comprising the total clinical spectrum of HIV infection, were utilized in the evaluation of six commercially available enzyme-linked immunosorbent assays (ELISA), as well as of four alternative assays, namely indirect immunofluorescence (IIF), passive hemagglutination (PHA), dot blot and Karpas AIDS cell test. The sensitivities ranged from 100% (Abbott and Roche ELISA) to 84.2% (PHA) and the specificities ranged from 99.3% (IIF) to 80.2% (PHA). The sensitivity and specificity of the PHA and the sensitivity of the Karpas cell test were significantly lower than those of the other tests. Although the IFF and dot blot had good sensitivities and specificities, the six ELISA were more attractive than those tests when other parameters such as ease of reading and duration of assay were considered.