ABSTRACT
Este artigo apresenta uma revisão integrativa das publicações científicas da última década, que investigaram os hábitos de sono, a ingestão alimentar e o estado nutricional de profissionais de enfermagem. Foram analisados artigos publicados em periódicos nacionais e internacionais no período de 2002 a 2014, disponibilizados na base de dados PubMed/MEDLINE (USA National Library of Medicine), Lilacs / SciELO (Scientific Eletronic Library Online) e Google Acadêmico. Trinta e um artigos preencheram os critérios estabelecidos. Na análise destes estudos foi identificada elevada prevalência de sobrepeso e obesidade, além de uma modificação negativa nos hábitos alimentares, bem como prejuízos na dinâmica do sono dos profissionais da área de enfermagem.
This article presents an integrative review of national and international scientific publications that investigate the sleep habits, the feed intake and nutritional status of nursing professionals. It was analyzed articles published in national and international journals in the period 2002 to 2014 and made available in the database PubMed / MEDLINE (USA National Library of Medicine), Lilacs / SciELO (Scientific Eletronic Library Online) and Google Scholar. Thirty one articles met the criteria. In the analysis of these studies it has been found a high prevalence of overweight and obesity, a negative change in the eating habits, as well as losses in the sleep patterns of nursing professionals.
En este artículo se presenta una revisión integradora de las publicaciones científicas nacionales e internacionales que investigan los hábitos de sueño, el consumo de alimento y el estado nutricional de los profesionales de enfermería. Se analizaron los artículos publicados en revistas nacionales e internacionales en el período de 2002 a 2014, disponibles en la base de datos PubMed / MEDLINE (USA Biblioteca Nacional de Medicina), Lilacs / SciELO (Scientific Eletronic Library Online) y Google Scholar. Treinta y uno artículos cumplieron con los criterios de inclusión. En el análisis de estos estudios se encontró una alta prevalencia de sobrepeso y obesidad, un cambio negativo en los hábitos alimenticios, así como prejuicios en la dinámica del sueño de los profesionales de enfermería.
Subject(s)
Penicillanic Acid/analysis , Penicillin G/metabolism , Phenylacetates/analysis , Chromatography, High Pressure Liquid , Enzymes, Immobilized/metabolism , Hydrogen-Ion Concentration , Hydrolysis , Mass Spectrometry , Penicillanic Acid/analogs & derivatives , Penicillin Amidase/metabolism , TemperatureABSTRACT
Particle size and enzyme protein loading are design parameters of enzyme immobilization affecting biocatalyst performance that can be varied within broad margins. Their effect on mass transfer limitations at different bulk penicillin G concentrations has been studied with glyoxyl agarose immobilized penicillin G acylase biocatalysts of average particle size of 5·10-5m and 10·10-4m at protein loadings from 15 to 130 mg/g gel. Internal diffusional restrictions were evaluated for such biocatalysts: Thiele modulus varied from 1.17 for the small particles at the lower protein load to 5.84 for the large particles at the higher protein load. Effectiveness factors at different bulk substrate concentrations were determined for all biocatalysts, values ranging from 0.78 for small particle size at 25 mM penicillin G to 0.15 for large particle size at 2 mM penicillin G. Enzyme protein loading had a strong impact on the effectiveness factors of immobilized penicillin G acylase, being it more pronounced in the case of large particle size biocatalysts. At conditions in which 6-aminopenicillanic acid is industrially produced, all biocatalysts tested were mass-transfer limited, being this information valuable for reactor design and performance evaluation.
Subject(s)
Penicillin Amidase , Penicillin Amidase/metabolism , Penicillin G/metabolism , Penicillin G/chemistry , Enzymes, Immobilized , Hydrolysis , Immunodiffusion/methodsABSTRACT
Search for anti-beta-lactamase and synthesis of newer penicillin were suggested to overcome resistance to penicillin in chemotherapy. It was found that clavulanic acid, an ant-beta-lactamase was ineffective due to its structural modification by bacteria. Thus, there is a need for the synthesis of newer pencillins. Retro-synthesis was inspired by the success of forward reaction i.e.conversion of penicillin G to 6-aminopenicillanic acid (6-APA) by biological process. In the present study a better enzymatic method of synthesis of newer pencillin by a beta-lactamase-free penicillin amidase produced by Alcaligenes sp. is attempted. Antibacterial and toxicological evaluation of the enzymatically synthesized beta-lactams are reported. Condensation of 6-APA with acyl donor was found to be effective when the reaction is run in dimethyl formamide (DMF 50% v/v) in acetate buffer (25 mM pH 5.0) at 37 degrees C. Periplasm entrapped in calcium alginate exihibited the highest yield (approximately 34%) in synthesis. The minimum inhibitory concentration of the synthetic products against Staphylococcus aureus and Salmonella typhi varied between 20-80 microg/ml. Some of the products exhibited antibacterial activity against enteric pathogens. It was interesting to note that product A was potent like penicillin G. LD50 value of three products (product A, B and C) was more than 12 mg/kg. Furthermore, these synthetic beta-lactams did not exihibit any adverse effect on house keeping enzymes viz., serum glutamate oxalacetate-trans-aminase, serum glutamate pyruvate -trans-aminase, acid phosphatase, alkaline phosphatase of the test animals. The hematological profile (RBC and WBC) of the test animals also remained unaffected.
Subject(s)
Alcaligenes/drug effects , Animals , Anti-Bacterial Agents/biosynthesis , Cells, Immobilized/enzymology , Lethal Dose 50 , Microbial Sensitivity Tests , Penicillin Amidase/metabolism , Staphylococcus aureus/drug effects , beta-Lactams/metabolismABSTRACT
Penicillin acylase (EC 3.5.1.11) catalyses the condensation of phenylacetic acid (PAA) and 6-aminopenicillanic acid (6-APA) to form benzylpenicillin (BP). Both PAA and 6-APA were found to form host-guest complexes with beta-methylcyclodextrin (beta m-CD) and gamma-cyclodextrin (gamma-CD) respectively. The rate of the reaction catalyzed by the enzyme remained unaffected if one of the substrates used was in the cyclodextrin complexed form. However, in this case, the reaction lasted longer and yielded about 20 per cent more products compared to the condensation reaction involving only uncomplexed substrates. There was distinct increase in the rate of formation of the antibiotic, if both substrates used are in CD-complexed form.
Subject(s)
Carbohydrates , Cyclodextrins , Penicillanic Acid/analogs & derivatives , Penicillin Amidase/metabolism , Penicillin G/metabolism , Phenylacetates/metabolism , Substrate SpecificityABSTRACT
Enzymatic parameters such as pH, temperature and substrate concentration were studied for the hydrolysis of 7-PADCA by penicillin G acylase. Optimum pH and temperature were 8.0 and 50 degrees C, respectively. Km value of soluble and immobilized enzyme for 7-PADCA was 2.3 x 10(-5) M and 7.5 x 10(-5) M, respectively. At 7-PADCA concentration of 5% and an IME: 7-PADCA ratio of 1:2.5, the hydrolysis was complete in 110 min.
Subject(s)
Cephalosporins/metabolism , Enzymes, Immobilized , Hydrogen-Ion Concentration , Hydrolysis , Penicillin Amidase/metabolism , TemperatureABSTRACT
Binding of penicillin amidase from E. coli 436 to aniline-, benzylamine- and phenylethylamine-Sepharose was studied. Binding of the enzyme to aniline-Sepharose was exclusively due to hydrophobic interactions. Benzylamine-Sepharose binds the enzyme due to affinity interactions in the absence of ammonium sulphate and due to hydrophobic interactions in the presence of ammonium sulphate. A conformational change in the penicillin amidase molecule due to ammonium sulphate there by exposing the side chain binding site as a hydrophobic core is suggested.