A novel assay for phosphoserine phosphatase exploiting serine acetyltransferase as the coupling enzyme

Phosphoserine phosphatase (PSP) catalyzes the final step of de novo L-serine biosynthesis— the hydrolysis of phosphoserine to serine and inorganic phosphate—in humans, bacteria, and plants. In published works, the reaction is typically monitored through the discontinuous malachite green phosphate assay or, more rarely, through a continuous assay that couples phosphate release to the phosphorolysis of a chromogenic nucleoside by the enzyme purine nucleoside phosphorylase (PNP). These assays suffer from numerous drawbacks, and both rely on the detection of phosphate. We describe a new continuous assay that monitors the release of serine by exploiting bacterial serine acetyltransferase (SAT) as a reporter enzyme. SAT acetylates serine, consuming acetyl-CoA and releasing CoA-SH. CoA-SH spontaneously reacts with Ellman’s reagent to produce a chromophore that absorbs light at 412 nm. The catalytic parameters estimated through the SAT-coupled assay are fully consistent with those obtained with the published methods, but the new assay exhibits several advantages. Particularly, it depletes L-serine, thus allowing more prolonged linearity in the kinetics. Moreover, as the SAT-coupled assay does not rely on phosphate detection, it can be used to investigate the inhibitory effect of phosphate on PSP

Working time satisfaction in aging nurses

Satisfaction with working time could represent an index of good balance between work and life and predict satisfactory work ability and endurance of aged workers. This study is aimed at checking whether elderly nurses who were satisfied with working hours had a better work ability index than those unsatisfied, and finding which factors were related to satisfaction of working time with reference to general \u201cwell being\u201d and/or \u201cprivate life\u201d. The study sample consisted of 3,174 female nurses recruited in six European countries within the Nurses\u2019 Early Exit Study. All were rotating shiftworkers (nights included) and 12.95 % were over 45 years of age. A composite questionnaire, including demands at work and in private life, working conditions, individual resources and alternatives to nursing profession, was administered to the participants at baseline and 1 yr later (Time 1). Work ability index (WAI) at time 1 was used as outcome, whereas age groups and satisfaction of working time at baseline were used as predictors, after adjusting for family status and number of children < 7yrs of age. Also \u201csatisfaction with working time\u201d at Time 1 was used as outcome, whereas working hours, job demand, leisure time, influence on planning rotas, family status, number of children, work/family conflicts, sleep at Time 0 were included as potential determinants. Conditional Random Forest analysis was used to evaluate high, moderate or weak importance of these determinants. Nurses satisfied with working time at time 0 showed a higher WAI (time1) than those unsatisfied in all age groups, also over 50. Less work/family conflicts and better quality and quantity sleep turned out to be the best predictors of satisfaction with working time. Consistently, the importance of the other predictors differs when the outcome is \u201csatisfaction with working time\u201d related to general well-being rather than to private life

Assessment of waveform similarity in clinical gait data. The linear fit method

The assessment of waveform similarity is a crucial issue in gait analysis for the comparison of kinematic or kinetic patterns with reference data. A typical scenario is in fact the comparison of a patient’s gait pattern with a relevant physiological pattern. This study aims to propose and validate a simple method for the assessment of waveform similarity in terms of shape, amplitude, and offset. The method relies on the interpretation of these three parameters, obtained through a linear fit applied to the two data sets under comparison plotted one against the other after time normalization. The validity of this linear fit method was tested in terms of appropriateness (comparing real gait data of 34 patients with cerebrovascular accident with those of 15 healthy subjects), reliability, sensitivity, and specificity (applying a cluster analysis on the real data). Results showed for thismethod good appropriateness, 94.1% of sensitivity, 93.3% of specificity, and good reliability. The LFM resulted in a simple method suitable for analysing the waveform similarity in clinical gait analysis

Immobilization of proteins in silica gel: Biochemical and biophysical properties

The development of silica-based sol-gel techniques compatible with the retention of protein structure and function started more than 20 years ago, mainly for the design of biotechnological devices or biomedical applications. Silica gels are optically transparent, exhibit good mechanical stability, are manufactured with different geometries, and are easily separated from the reaction media. Biomolecules encapsulated in silica gel normally retain their structural and functional properties, are stabilized with respect to chemical and physical insults, and can sometimes exhibit enhanced activity in comparison to the soluble form. This review briefly describes the chemistry of protein encapsulation within the pores of a silica gel three-dimensional network, the mechanism of interaction between the protein and the gel matrix, and its effects on protein structure, function, stability and dynamics. The main applications in the field of biosensor design are described. Special emphasis is devoted to silica gel encapsulation as a tool to selectively stabilize subsets of protein conformations for biochemical and biophysical studies, an application where silica-based encapsulation demonstrated superior performance with respect to other immobilization techniques

Iron metabolism at the interface between host and pathogen: From nutritional immunity to antibacterial development

Nutritional immunity is a form of innate immunity widespread in both vertebrates and invertebrates. The term refers to a rich repertoire of mechanisms set up by the host to inhibit bacterial proliferation by sequestering trace minerals (mainly iron, but also zinc and manganese). This strategy, selected by evolution, represents an effective front-line defense against pathogens and has thus inspired the exploitation of iron restriction in the development of innovative antimicrobials or enhancers of antimicrobial therapy. This review focuses on the mechanisms of nutritional immunity, the strategies adopted by opportunistic human pathogen Staphylococcus aureus to circumvent it, and the impact of deletion mutants on the fitness, infectivity, and persistence inside the host. This information finally converges in an overview of the current development of inhibitors targeting the different stages of iron uptake, an as-yet unexploited target in the field of antistaphylococcal drug discovery

Manual de implantação do treino e visita (T&V).

A visão sobre transferência de tecnologia na Embrapa; A metodologia treino e visita (T&V); O treino e visita em sua forma original; Adaptação do treino e visita para o Brasil; Consolidação do T&V soja/grãos - a experiência da Embrapa Soja; Programa de profissionalização do produtor rural (PPRR) da COPACOL; Projeto grãos da EMATER-Paraná; A aplicação da metodologia em diferentes projetos; Projeto T&V café; Projeto T&V saúde, alimentação e geração de renda; Projeto T&V girassol; Projeto T&V pecuária de corte e de leite no Paraná; Projeto T&V sementes; Projeto T&V grãos no Rio Grande do Sul; Estratégias para a implantação do T&V; Definição do foco; Criação do grupo gestor; Criação do comitê técnico; Pré-requisitos para a implantação do T&V; Anexo 1 - Modelo de relatório do T&V grãos - safra 2002/03; Anexo 2 - Modelo de relatório do T&V - saúde, alimentação e geração de renda; Anexo 3 - Modelo de marco zero do Projeto Grãos/EMATER-PR.bitstream/item/80261/1/Manual-de-implantacao-do-treino-e-visita-V-T.pd

Iron metabolism at the interface between host and pathogen: From nutritional immunity to antibacterial development

Nutritional immunity is a form of innate immunity widespread in both vertebrates and invertebrates. The term refers to a rich repertoire of mechanisms set up by the host to inhibit bacterial proliferation by sequestering trace minerals (mainly iron, but also zinc and manganese). This strategy, selected by evolution, represents an effective front-line defense against pathogens and has thus inspired the exploitation of iron restriction in the development of innovative antimicrobials or enhancers of antimicrobial therapy. This review focuses on the mechanisms of nutritional immunity, the strategies adopted by opportunistic human pathogen Staphylococcus aureus to circumvent it, and the impact of deletion mutants on the fitness, infectivity, and persistence inside the host. This information finally converges in an overview of the current development of inhibitors targeting the different stages of iron uptake, an as-yet unexploited target in the field of antistaphylococcal drug discovery

A New Kind of Quinonic-Antibiotic Useful Against Multidrug-Resistant S. aureus and E. faecium Infections

Indexación: Scopus.A rapid emergence of resistant bacteria is occurring worldwide, endangering the efficacy of antibiotics and reducing the therapeutic arsenal available for treatment of infectious diseases. In the present study, we developed a new class of compounds with antibacterial activity obtained by a simple, two step synthesis and screened the products for in vitro antibacterial activity against ATCC® strains using the broth microdilution method. The compounds exhibited minimum inhibitory concentrations (MIC) of 1⁻32 μg/mL against Gram-positive ATCC® strains. The structure⁻activity relationship indicated that the thiophenol ring is essential for antibacterial activity and the substituents on the thiophenol ring module, for antibacterial activity. The most promising compounds detected by screening were tested against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium (VREF) clinical isolates. We found remarkable activity against VREF for compounds 7 and 16, were the MIC50/90 were 2/4 µg/mL and 4/4 µg/mL, respectively, while for vancomycin the MIC50/90 was 256/512 µg/mL. Neither compound affected cell viability in any of the mammalian cell lines at any of the concentrations tested. These in vitro data show that compounds 7 and 16 have an interesting potential to be developed as new antibacterial drugs against infections caused by VREF.https://www.mdpi.com/1420-3049/23/7/177