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3.
Materials (Basel) ; 15(11)2022 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-35683301

RESUMO

During interventions to improve the energy efficiency of cultural heritage, it is common to use methodologies that are used for current buildings with different thermal behaviour. For this reason, research has been carried out on the thermal behaviour of old brick walls by carrying out thermal flow tests in the laboratory on brickwork specimens, in order to compare the behaviour of handmade bricks and mechanical bricks from more than a century ago, and to analyse the relationship between the values of thermal conductivity, humidity, density and porosity, as well as to compare these results with those obtained by applying the procedure of the EN-1745 standard. It was concluded that bricks behave thermally differently, depending on the manufacturing process: handmade or mechanical, in both types of brick it was found that the higher the moisture content and density were, the higher the brick's thermal conductivity value. It has also been concluded that old bricks have thermal conductivity values different from those indicated in EN-1745 as a function of density, and that the ratio detected in these specimens in the dry state and in the wet state does not conform to the processes indicated in the standard. With regard to porosity, it is important to note that the greater the closed porosity, the lower the conductivity. It has been concluded that in order to intervene in cultural heritage buildings, it is necessary to carry out a specific study of the behaviour of the systems with which they were constructed.

5.
Front Physiol ; 13: 852946, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35444561

RESUMO

Misshaped red blood cells (RBCs), characterized by thorn-like protrusions known as acanthocytes, are a key diagnostic feature in Chorea-Acanthocytosis (ChAc), a rare neurodegenerative disorder. The altered RBC morphology likely influences their biomechanical properties which are crucial for the cells to pass the microvasculature. Here, we investigated blood cell deformability of five ChAc patients compared to healthy controls during up to 1-year individual off-label treatment with the tyrosine kinase inhibitor dasatinib or several weeks with lithium. Measurements with two microfluidic techniques allowed us to assess RBC deformability under different shear stresses. Furthermore, we characterized leukocyte stiffness at high shear stresses. The results showed that blood cell deformability-including both RBCs and leukocytes - in general was altered in ChAc patients compared to healthy donors. Therefore, this study shows for the first time an impairment of leukocyte properties in ChAc. During treatment with dasatinib or lithium, we observed alterations in RBC deformability and a stiffness increase for leukocytes. The hematological phenotype of ChAc patients hinted at a reorganization of the cytoskeleton in blood cells which partly explains the altered mechanical properties observed here. These findings highlight the need for a systematic assessment of the contribution of impaired blood cell mechanics to the clinical manifestation of ChAc.

6.
mSphere ; 7(1): e0097821, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-34986320

RESUMO

Horizontal transfer of bacterial plasmids generates genetic variability and contributes to the dissemination of the genes that enable bacterial cells to develop antimicrobial resistance (AMR). Several aspects of the conjugative process have long been known, namely, those related to the proteins that participate in the establishment of cell-to-cell contact and to the enzymatic processes associated with the processing of plasmid DNA and its transfer to the recipient cell. In this work, we describe the roles of newly identified proteins that influence the conjugation of several plasmids. Genes encoding high-molecular-weight bacterial proteins that contain one or several immunoglobulin-like domains (Big) are located in the transfer regions of several plasmids that usually harbor AMR determinants. These Big proteins are exported to the external medium and target two extracellular organelles: the flagella and conjugative pili. The plasmid gene-encoded Big proteins facilitate conjugation by reducing cell motility and facilitating cell-to-cell contact by binding both to the flagella and to the conjugative pilus. They use the same export machinery as that used by the conjugative pilus components. In the examples characterized in this paper, these proteins influence conjugation at environmental temperatures (i.e., 25°C). This suggests that they may play relevant roles in the dissemination of plasmids in natural environments. Taking into account that they interact with outer surface organelles, they could be targeted to control the dissemination of different bacterial plasmids carrying AMR determinants. IMPORTANCE Transmission of a plasmid from one bacterial cell to another, in several instances, underlies the dissemination of antimicrobial resistance (AMR) genes. The process requires well-characterized enzymatic machinery that facilitates cell-to-cell contact and the transfer of the plasmid. Our paper identifies novel plasmid gene-encoded high-molecular-weight proteins that contain an immunoglobulin-like domain and are required for plasmid transmission. They are encoded by genes on different groups of plasmids. These proteins are exported outside the cell. They bind to extracellular cell appendages such as the flagella and conjugative pili. Expression of these proteins reduces cell motility and increases the ability of the bacterial cells to transfer the plasmid. These proteins could be targeted with specific antibodies to combat infections caused by AMR microorganisms that harbor these plasmids.


Assuntos
Anti-Infecciosos , Conjugação Genética , Bactérias/genética , Transferência Genética Horizontal , Domínios de Imunoglobulina , Plasmídeos/genética
8.
Commun Biol ; 4(1): 1295, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34785760

RESUMO

Enteroaggregative Escherichia coli (EAEC) strains are one of the diarrheagenic pathotypes. EAEC strains harbor a virulence plasmid (pAA2) that encodes, among other virulence determinants, the aggR gene. The expression of the AggR protein leads to the expression of several virulence determinants in both plasmids and chromosomes. In this work, we describe a novel mechanism that influences AggR expression. Because of the absence of a Rho-independent terminator in the 3'UTR, aggR transcripts extend far beyond the aggR ORF. These transcripts are prone to PNPase-mediated degradation. Structural alterations in the 3'UTR result in increased aggR transcript stability, leading to increased AggR levels. We therefore investigated the effect of increased AggR levels on EAEC virulence. Upon finding the previously described AggR-dependent virulence factors, we detected novel AggR-regulated genes that may play relevant roles in EAEC virulence. Mutants exhibiting high AggR levels because of structural alterations in the aggR 3'UTR show increased mobility and increased pAA2 conjugation frequency. Furthermore, among the genes exhibiting increased fold change values, we could identify those of metabolic pathways that promote increased degradation of arginine, fatty acids and gamma-aminobutyric acid (GABA), respectively. In this paper, we discuss how the AggR-dependent increase in specific metabolic pathways activity may contribute to EAEC virulence.


Assuntos
Proteínas de Escherichia coli/genética , Escherichia coli/genética , Escherichia coli/patogenicidade , Transativadores/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Transativadores/metabolismo , Virulência/genética
9.
Foods ; 10(6)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201411

RESUMO

The authors would like to make the following correction to the published paper [1]: a few words should be corrected in the abstract, pages 7 and 9 [...].

10.
Med Clin (Barc) ; 157(12): 598, 2021 12 24.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-34074483

Assuntos
Neoplasias , Face , Humanos
12.
Int J Food Microbiol ; 348: 109203, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-33930835

RESUMO

In the UK and Northern Europe, ripening oats can become contaminated with T-2 and HT-2 mycotoxins, produced mainly by Fusarium langsethiae. There are indicative levels related to the maximum limits for oat grain for these toxins. The objectives of this study were to examine the effect of interacting conditions of temperature (10-30 °C) and water activity (aw, 0.995-0.90) on (a) lag times prior to growth, (b) growth and (c) T-2 and HT-2 toxins by two strains of F. langsethiae isolated from oats in the UK and compare this with the type strain (Fl201059) which has been genomically sequenced, and (d) develop (and validated with published data) a probabilistic models for impacts of temperature × aw on growth and toxin production. All three strains had an optimum aw range and temperature of 0.995-0.98 and 25 °C for growth. For T-2 + HT-2 production these were 0.995 aw and 20 °C. Overall, the type strain produced higher amounts of T-2 + HT-2 with a HT-2/T-2 ratio of up to 76. Using this study data sets and those from the literature, probabilistic models were developed and validated for growth and T-2 + HT-2 toxin production in relation to temperature × aw conditions. These models, when applied in stored oats, will be beneficial in determining the conditions on the relative level of risk of contamination with these two toxins in the context of the EU indicative maximum levels.


Assuntos
Avena/microbiologia , Grão Comestível/microbiologia , Fusarium/metabolismo , Micotoxinas/análise , Toxina T-2/análogos & derivados , Europa (Continente) , Fusarium/classificação , Fusarium/isolamento & purificação , Toxina T-2/análise , Temperatura , Água
14.
Int J Mol Sci ; 22(5)2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673442

RESUMO

This article includes an updated review of the classification, uses and side effects of surfactants for their application in the cosmetic, personal care and pharmaceutical industries. Based on their origin and composition, surfactants can be divided into three different categories: (i) synthetic surfactants; (ii) bio-based surfactants; and (iii) microbial biosurfactants. The first group is the most widespread and cost-effective. It is composed of surfactants, which are synthetically produced, using non-renewable sources, with a final structure that is different from the natural components of living cells. The second category comprises surfactants of intermediate biocompatibility, usually produced by chemical synthesis but integrating fats, sugars or amino acids obtained from renewable sources into their structure. Finally, the third group of surfactants, designated as microbial biosurfactants, are considered the most biocompatible and eco-friendly, as they are produced by living cells, mostly bacteria and yeasts, without the intermediation of organic synthesis. Based on the information included in this review it would be interesting for cosmetic, personal care and pharmaceutical industries to consider microbial biosurfactants as a group apart from surfactants, needing specific regulations, as they are less toxic and more biocompatible than chemical surfactants having formulations that are more biocompatible and greener.


Assuntos
Cosméticos/química , Tensoativos , Bactérias/química
15.
Eur J Dermatol ; 31(6): 785-790, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-35107070

RESUMO

BACKGROUND: Oral propranolol accelerates the involution of infantile haemangiomas (IHs). However, it is not clear whether IHs treated with oral propranolol are associated with fewer sequelae than when left untreated. OBJECTIVES: To quantify and describe sequelae associated with IHs treated with oral propranolol, and to explore whether treated IHs are associated with fewer sequelae than untreated IHs. MATERIALS & METHODS: This multicentre, retrospective, cohort study included patients with IH treated with oral propranolol ≥2 mg/kg for at least six months, with photographic images available at baseline and at age 4-5 years. A historical comparison cohort comprised 185 patients with untreated IHs. Main outcomes/measures were: IH features, treatment characteristics and type/degree of sequelae. RESULTS: Oral propranolol, most commonly at 2 mg/kg/day (mean duration: nine months), was initiated in 171 patients (mean age: 6.02 months). After treatment, 125 of 171 (73.1%) IHs were associated with no/minimal sequelae. The most common sequelae were telangiectasia (78%), fibrofatty tissue (37%) and anetodermic skin (28%). Deep IHs were associated with significantly fewer sequelae than other subtypes. Ulceration appeared to increase the likelihood of severe sequelae. IHs with a stepped border was associated with more severe sequelae than those with a progressive border (44% versus 27%, p < 0.05). Treated IHs resolved without sequelae or were associated with a sequela that did not need correction in 27.7% more cases than untreated IHs (RR: 1.61; p < 0.001). CONCLUSION: Among IHs treated with oral propranolol, 73% resolved without, or were associated with minimal sequelae. Deep IHs were associated fewer sequelae than other subtypes. Oral propranolol decreased the likelihood of IH sequelae requiring correction.


Assuntos
Antineoplásicos/administração & dosagem , Hemangioma/tratamento farmacológico , Propranolol/administração & dosagem , Neoplasias Cutâneas/tratamento farmacológico , Administração Oral , Feminino , Hemangioma/patologia , Humanos , Lactente , Masculino , Estudos Retrospectivos , Neoplasias Cutâneas/patologia , Resultado do Tratamento
16.
Microbiol Res ; 242: 126614, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33045681

RESUMO

The presence of biosurfactants produced by a Bacillus strain in corn steep liquor (CSL), a wastewater stream of the corn milling process, has been recently discovered. However, the species responsible for their production has not been identified at the moment. Therefore, in this work, the Bacillus strain isolated from CSL, with capacity to produce biosurfactants, was subjected to amplification and sequence analysis of the 16S rRNA, being identified as Aneurinibacillus aneurinilyticus. This strain has been proved to be endospore forming and thermophile, what would explain its presence in the commercial CSL. It was observed that the strain under evaluation has the ability to produce both cell-bound and extracellular biosurfactant extracts, which were characterized in this work. The electrospray ionization mass spectrometry (ESI) analysis of the biosurfactant extracts revealed that the extracellular biosurfactant produced by Aneurinibacillus aneurinilyticus is composed by a mixture of lipopeptides, containing C16 and C18 fatty acids and amino acids, including valine, phenylalanine, proline, cysteine, histidine, aspartic acid/asparagine, alanine, glycine, leucine/isoleucine, with biomarkers between 1025-458 m/z. Conversely, the cell-bound biosurfactant extract produced by Aneurinibacillus aneurinilyticus was composed by the cyclic decapeptide gramicidin S, with a characteristic peak at 571 m/z, and lipopeptides with characteristic peaks between 1034-705 m/z, containing alanine, glycine, cysteine, serine, proline, aspartic acid/asparagine, similarly to the amino acid sequence of the extracellular biosurfactant extract.


Assuntos
Bacillales/isolamento & purificação , Bacillales/metabolismo , Tensoativos/química , Tensoativos/metabolismo , Zea mays/microbiologia , Aminoácidos/análise , Bacillales/genética , Bacillus/classificação , Bacillus/genética , Bacillus/isolamento & purificação , Ácidos Graxos/análise , Gramicidina/metabolismo , Lipopeptídeos/análise , RNA Ribossômico 16S/genética , Espectrometria de Massas por Ionização por Electrospray
17.
ACS Omega ; 5(48): 31381-31390, 2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33324849

RESUMO

In this work, five biosurfactant extracts, obtained from different sources, all of them with demonstrated antimicrobial properties, were characterized and subjected to a cytotoxic study using mouse fibroblast cells (NCTC clone 929). Biosurfactant extracts obtained directly from corn steep water (CSW) showed similar surfactant characteristics to those of the extracellular biosurfactant extract produced by Bacillus isolated from CSW and grown in tryptic soy broth, observing that they are amphoteric, consisting of viscous and yellowish liquid with no foaming capacity. Contrarily, cell-bound biosurfactant extracts produced from Lactobacillus pentosus or produced by Bacillus sp isolated from CSW are nonionic, consisting of a white powder with foaming capacity. All the biosurfactants possess a similar fatty acid composition. The cytotoxic test revealed that the extracts under evaluation, at a concentration of 1 g/L, were not cytotoxic for fibroblasts (fibroblast growth > 90%). The biosurfactant extract obtained from CSW with ethyl acetate, at 1 g/L, showed the highest cytotoxic effect but above the cytotoxicity limit established by the UNE-EN-ISO10993-5. It is remarkable that the cell-bound biosurfactant produced by L. pentosus, at a concentration of 1 g/L, promoted the growth of the fibroblast up to 113%.

18.
Foods ; 9(12)2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33256051

RESUMO

In winemaking, oenological tannins are used to preserve wine colour by enhancing the antioxidant activity, taking part in copigmentation, and forming polymeric pigments with anthocyanins. As a novel processing aid, in this study, a biosurfactant extract was evaluated as a solubilizing and stabilizing agent of anthocyanins in red wine. The biosurfactant extract under evaluation was obtained from a fermented residual stream of the corn milling industry named corn steep liquor (CSL). Two red winegrape varieties (Vitis vinifera L. cv. Aglianico and Cabernet sauvignon) were studied for anthocyanin content and profile, and colour traits, during simulated skin maceration for 7 days at 25 °C, as well as polymerization and copigmentation at the end of maceration. A model wine solution was used as a control, which was added either with the CSL biosurfactant or with four different oenological tannins (from grape skin, grape seed, quebracho, and acacia). The results showed that CSL biosurfactant addition improved the colour properties of skin extracts by the formation of more stable compounds mainly through copigmentation interactions. These preliminary results highlighted that the effectiveness of CSL biosurfactant is variety-dependent; however, there is no significant protection of individual anthocyanin compounds as observed for delphinidin and petunidin forms using quebracho tannin.

19.
Front Mol Biosci ; 7: 160, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32850954

RESUMO

Gene duplications are a feature of bacterial genomes. In the present work we analyze the extent of gene duplications in the genomes of three microorganisms that belong to the Firmicutes phylum and that are etiologic agents of several nosocomial infections: Staphylococcus aureus, Enterococcus faecium, and Enterococcus faecalis. In all three groups, there is an irregular distribution of duplications in the genomes of the strains analyzed. Whereas in some of the strains duplications are scarce, hundreds of duplications are present in others. In all three species, mobile DNA accounts for a large percentage of the duplicated genes: phage DNA in S. aureus, and plasmid DNA in the enterococci. Duplicates also include core genes. In all three species, a reduced group of genes is duplicated in all strains analyzed. Duplication of the deoC and rpmG genes is a hallmark of S. aureus genomes. Duplication of the gene encoding the PTS IIB subunit is detected in all enterococci genomes. In E. faecalis it is remarkable that the genomes of some strains encode duplicates of the prgB and prgU genes. They belong to the prgABCU cluster, which responds to the presence of the peptide pheromone cCF10 by expressing the surface adhesins PrgA, PrgB, and PrgC.

20.
Rev. chil. cardiol ; 39(2): 105-113, ago. 2020. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1138523

RESUMO

ANTECEDENTES: Las unidades de Cardiología intervencional han evidenciado un número creciente de procedimientos, cada vez más variados y complejos, lo cual podría eventualmente generar daños a los profesionales ocupacionalmente expuestos a radiaciones ionizantes (POEs) de no contar con los adecuados elementos de radioprotección y un uso correcto de ellos. OBJETIVO: Caracterizar la disponibilidad y utilización de los elementos de radioprotección y dosimetría de unidades de cardiología intervencionista de centros Sudamericanos. MATERIAL Y MÉTODOS: Se realizó una encuesta autoaplicada a 139 POEs, de ambos sexos de 7 países, a través de una plataforma on-line, se les consultó sobre características demográficas, dosimétricas y de radioprotección. RESULTADOS: Los elementos de radioprotección más tradicionales; delantales y cuellos plomados se utilizaron un 99,5 % y 98,4 % respectivamente, aquellos elementos más recientes como gafas, gorros y paños plomados solo alcanzaron un 36,8 %, 6,8 % y 34,2%, de utilización respectivamente, en cuanto a la utilización de los dosímetros, solo un 7,9 % lo hace apegado a las normas de la Organización Internacional de Energía Atómica (OIEA). CONCLUSIÓN: Se constató en la muestra analizada una falta de elementos de radioprotección y un uso inadecuado de ellos, urge realizar intervenciones educativas y técnicas para mejorar estos datos.


BACKGROUND: Due to the increasing number of interventional cardiology procedures currently performed, health professionals (POE) are exposed to ionizing radiation unless adequate protective elements are used. AIM: to describe the use of radioprotection elements and dosimetry in interventional cardiology laboratories in South America. METHODS: A self-administered survey was performed on 139 POE of both sexes and 7 countries using an online platform. Demographic data, dosimetry and characteristics of radioprotection analyzed. RESULTS: Commonly used radioprotective elements (lead aprons and collars) were used in 99.5% and 98% respectively. Recently introduced protection elements like lead goggles, caps and drapery were used in 36.8, 6.8 and 34.2% , respectively. Dosimetry according to the International Atomic Energy Commission (OIAE) was performed in only 7.9% of the procedures. CONCLUSION: there is a severe lack of adequate radioprotection during interventional cardiology procedures. Urgent measures, including technical implementation and educational interventions are needed to improve radioprotection in interventional cardiology.


Assuntos
Humanos , Masculino , Feminino , Adulto , Proteção Radiológica/métodos , Radiografia Intervencionista/efeitos adversos , Exposição Ocupacional/prevenção & controle , Serviço Hospitalar de Cardiologia , Doses de Radiação , Radiação Ionizante , Proteção Radiológica/instrumentação , Proteção Radiológica/estatística & dados numéricos , América do Sul , Projetos Piloto , Inquéritos e Questionários , Autorrelato , Equipamento de Proteção Individual
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