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The di-iron RIC protein (YtfE) of Escherichia coli interacts with the DNA-binding protein from starved cells (Dps) to diminish RIC-protein-mediated redox stress
The RIC (Repair of Iron Clusters) protein of Escherichia coli is a di-iron hemerythrin-like protein that has a proposed function in repairing stress-damaged iron-sulphur clusters. In this work, we performed a Bacterial Two Hybrid screening to search for RIC-protein
interaction partners in E. coli. As a result, the DNA-binding protein from starved cells (Dps) was identified and its potential interaction with RIC was tested by BACTH, Bimolecular-Fluorescence-Complementation and pull-down assays. Using the activity of two Fe-S-containing enzyme as indicators of cellular Fe-S cluster damage, we observed that strains with single deletions of ric or dps have significantly lower aconitase and fumarase activities. In contrast, the double ric dps mutant strain displayed no loss of aconitase and fumarase activity with respect to the wild type. Additionally, while
complementation of the ric dps double mutant with ric led to a severe loss of aconitase activity, this effect was no longer observed when a gene encoding a di-iron site variant of the RIC protein was employed. The dps mutant exhibited a large increase in ROS levels, but this increase was eliminated when ric was also inactivated. Absence of other iron storage proteins, or of peroxidase and catalases, had no impact on RIC-mediated redox
stress induction. Hence, we show that RIC interacts with Dps in a manner that serves to protect E. coli from RIC-protein-induced ROS
Entomopathogenic fungi associated with the main insect pest in the Northeast of Portugal: preliminary results
Due to the problems caused by the use of chemical insecticides for humans and environment alternative pest control methods are an important topic of research. The use of microbial insecticides especially fungal agents are an attractive and promising alternative for biological control of insect pests. The aim of this work was to identify naturally occurring entomophatogenic fungi on the olive moth, Prays oleae Bern., in the northeast of Portugal, as first step to select biological control agent again this olive pest. The experimental work was carried out during 2007 in the three generation of the insect (phyllophagous, anthophagous and carpophagous generation). In each generation P. oleae larvae and pupae were collected in different groves and were put in glass vials in a climatic chamber with a photoperiod of 12h light:12h dark, 22ºC (light): 16ºC (dark) and 60% relative humidity, until emergency of the adults. From dead larvae, fungi were isolated on PDA plates and incubated at room temperature. Pure cultures were morphological and molecularly identified based on the ITS region of the rDNA. From the identified species Beauveria bassiana Vuill. and Cordyceps sinensis (Berk.) Sacc. were the most promising being B. bassiana the most abundant one.This work was partially financed by the project INTERREG III
A Instituição através de uma caderneta de cromos
Existem variadas formas de comunicação para dar a conhecer uma instituição, que seja ela privada ou pública. Considerando por um lado a sua missão e por outro lado o seu pequeno orçamento, o Centro Ciência Viva do Algarve (CCVAlg) optou por desenvolver um projeto que permitisse criar um produto educativo e lúdico e ao mesmo tempo transmitir a imagem de uma instituição promotora da transferência de conhecimento científico. Nesse sentido e de forma a apresentar um produto multidisciplinar que aproveitasse as especificidades da região, foi decidido desenvolver um projeto sobre a Ria Formosa, que além de oferecer um ambiente natural de grande riqueza também permite abordar temas como a economia, a história, a arquitetura ou ainda a geologia, entre outros. De seguida, foi necessário encontrar não só os parceiros que possuam os conhecimentos científicos que se pretendia transmitir mas igualmente o parceiro que desenvolvesse o suporte que alberga-se o projeto. Os parceiros científicos foram naturalmente surgindo, tratando-se de entidades que são reconhecidas pelo seu trabalho no sistema lagunar de ilhas barreiras da Ria Formosa, como é o caso do Parque Natural da Ria Formosa (PNRF-ICNF), da Universidade do Algarve (UALG) e da Associação RIAS. Quanto ao parceiro técnico, o CCVAlg teve a sorte de ser contactado pela empresa COLARA que desenvolve cadernetas digitais de cromes, produtos que respondem perfeitamente ao objetivo de associar uma vertente lúdica à vertente educativa. Assim nasceu a caderneta digital de cromes sobre a Ria Formosa que integra i) o conhecimento científico; ii) a divulgação científica; iii) a educação não formal e interativa e iv) a comunicação institucional. O lançamento da caderneta terá lugar na 1a semana da Ria Formosa organizada pelo Instituto de Conservação da Natureza e da Floresta que decorrerá de 4 a 8 de Abril nos 5 concelhos que abrigam a Ria Formosa.Acknowledgement to Colara companyinfo:eu-repo/semantics/publishedVersio
Myocardial infarction affects Cx43 content of extracellular vesicles secreted by cardiomyocytes
Ischemic heart disease has been associated with an impairment on intercellular communication mediated by both gap junctions and extracellular vesicles. We have previously shown that connexin 43 (Cx43), the main ventricular gap junction protein, assembles into channels at the extracellular vesicle surface, mediating the release of vesicle content into target cells. Here, using a comprehensive strategy that included cell-based approaches, animal models and human patients, we demonstrate that myocardial ischemia impairs the secretion of Cx43 into circulating, intracardiac and cardiomyocyte-derived vesicles. In addition, we show that ubiquitin signals Cx43 release in basal conditions but appears to be dispensable during ischemia, suggesting an interplay between ischemia-induced Cx43 degradation and secretion. Overall, this study constitutes a step forward for the characterization of the signals and molecular players underlying vesicle protein sorting, with strong implications on long-range intercellular communication, paving the way towards the development of innovative diagnostic and therapeutic strategies for cardiovascular disorders
Contribution of Efflux to the Emergence of Isoniazid and Multidrug Resistance in Mycobacterium tuberculosis
Multidrug resistant (MDR) tuberculosis is caused by Mycobacterium tuberculosis resistant to isoniazid and rifampicin, the two most effective drugs used in tuberculosis therapy. Here, we investigated the mechanism by which resistance towards isoniazid develops and how overexpression of efflux pumps favors accumulation of mutations in isoniazid targets, thus establishing a MDR phenotype. The study was based on the in vitro induction of an isoniazid resistant phenotype by prolonged serial exposure of M. tuberculosis strains to the critical concentration of isoniazid employed for determination of drug susceptibility testing in clinical isolates. Results show that susceptible and rifampicin monoresistant strains exposed to this concentration become resistant to isoniazid after three weeks; and that resistance observed for the majority of these strains could be reduced by means of efflux pumps inhibitors. RT-qPCR assessment of efflux pump genes expression showed overexpression of all tested genes. Enhanced real-time efflux of ethidium bromide, a common efflux pump substrate, was also observed, showing a clear relation between overexpression of the genes and increased efflux pump function. Further exposure to isoniazid resulted in the selection and stabilization of spontaneous mutations and deletions in the katG gene along with sustained increased efflux activity. Together, results demonstrate the relevance of efflux pumps as one of the factors of isoniazid resistance in M. tuberculosis. These results support the hypothesis that activity of efflux pumps allows the maintenance of an isoniazid resistant population in a sub-optimally treated patient from which isoniazid genetically resistant mutants emerge. Therefore, the use of inhibitors of efflux should be considered in the development of new therapeutic strategies for preventing the emergence of MDR-TB during treatment
Multidifferential study of identified charged hadron distributions in -tagged jets in proton-proton collisions at 13 TeV
Jet fragmentation functions are measured for the first time in proton-proton
collisions for charged pions, kaons, and protons within jets recoiling against
a boson. The charged-hadron distributions are studied longitudinally and
transversely to the jet direction for jets with transverse momentum 20 GeV and in the pseudorapidity range . The
data sample was collected with the LHCb experiment at a center-of-mass energy
of 13 TeV, corresponding to an integrated luminosity of 1.64 fb. Triple
differential distributions as a function of the hadron longitudinal momentum
fraction, hadron transverse momentum, and jet transverse momentum are also
measured for the first time. This helps constrain transverse-momentum-dependent
fragmentation functions. Differences in the shapes and magnitudes of the
measured distributions for the different hadron species provide insights into
the hadronization process for jets predominantly initiated by light quarks.Comment: All figures and tables, along with machine-readable versions and any
supplementary material and additional information, are available at
https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-013.html (LHCb
public pages
Study of the decay
The decay is studied
in proton-proton collisions at a center-of-mass energy of TeV
using data corresponding to an integrated luminosity of 5
collected by the LHCb experiment. In the system, the
state observed at the BaBar and Belle experiments is
resolved into two narrower states, and ,
whose masses and widths are measured to be where the first uncertainties are statistical and the second
systematic. The results are consistent with a previous LHCb measurement using a
prompt sample. Evidence of a new
state is found with a local significance of , whose mass and width
are measured to be and , respectively. In addition, evidence of a new decay mode
is found with a significance of
. The relative branching fraction of with respect to the
decay is measured to be , where the first
uncertainty is statistical, the second systematic and the third originates from
the branching fractions of charm hadron decays.Comment: All figures and tables, along with any supplementary material and
additional information, are available at
https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-028.html (LHCb
public pages
Measurement of the ratios of branching fractions and
The ratios of branching fractions
and are measured, assuming isospin symmetry, using a
sample of proton-proton collision data corresponding to 3.0 fb of
integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The
tau lepton is identified in the decay mode
. The measured values are
and
, where the first uncertainty is
statistical and the second is systematic. The correlation between these
measurements is . Results are consistent with the current average
of these quantities and are at a combined 1.9 standard deviations from the
predictions based on lepton flavor universality in the Standard Model.Comment: All figures and tables, along with any supplementary material and
additional information, are available at
https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-039.html (LHCb
public pages
Exercise but not metformin improves health-related quality of life and mood states in older adults with type 2 diabetes
The aim of this cohort study is to analyse the effect of three types of treatment: (i) exercise training with multicomponent exercise (E); (ii) pharmacologic treatment with oral hypoglycaemic drug - metformin (M); and (iii) a combined therapy - exercise and metformin (E + M) on health-related quality of life (HRQoL) and mood states in older adults with type 2 diabetes (T2D) with comorbidity in an early stage of the disease. Participants (n = 284) underwent 1 of the following 3 conditions: (i) E (n = 59) trained three times/week; (ii) M (n = 30) used 850 mg of metformin twice daily; and (iii) E + M (n = 195) combined exercise and metformin. Furthermore, participants completed baseline and 2-year follow-up evaluations including a Shortform Health Survey 36, Profile of Mood States - Short-form, the health history questionnaires, anthropometric, and blood biochemistry. E and E + M revealed improved mood states, with large effect size on the vigour domain, and moderate effect size in the anger and total mood disturbance (TMD) domains (P 0.05). Metformin had no significant effect on the self-referred HRQoL in T2D participants aged above 60 years, in an early stage of the disease. The E and E + M were the most effective long-term therapies to improve mood states and HRQoL in older adults with T2D.info:eu-repo/semantics/publishedVersio
Antihypertensive monotherapy or combined therapy: which is more effective on functional status?
Background: This study aims to analyze the effects of anti-hypertensive monotherapy and combined therapy on functional status, and cardiovascular risk outcomes in older adults. Methods: This longitudinal non-randomized cohort study, involved hypertensive older adults (n = 440) aged 60 or more years with comorbidities. Participants underwent a community exercise training program and one of the following 2 conditions: i) use of daily mono-dose angiotensin-converting enzyme inhibitors (ACEi; n= 232); ii) combined therapy including ACEi plus other class agent (Combined; n= 208). Baseline and 2-year follow-up evaluations included the functional fitness, health-related quality of life (HRQoL), health history questionnaires, anthropometric and hemodynamic profile. Results: Both experimental groups have significantly improved physical functional status, and have significantly decreased blood pressure and waist circumference. ACEi group has significantly reduced body mass and body mass index, the Combined group significantly reduced the waist-to-hip ratio. Additionally, both groups perceived better physical HRQoL. Conclusions: Functional status has improved with ACEi medication and exercise training, regardless the ACEi medication therapy. Exercise training plus ACEi antihypertensive therapy should be recommended into the standard prescription practice to reduce the rate of physical disability among hypertensive older adults
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