Selection of an antimicrobial culture to be used in the prevention of neonatal listeriosis

The capacity of lactic acid bacteria to produce acidic products and/or secrete antimicrobial compounds is important in the impairment of vaginal colonization by pathogens. Vaginal pH is normally acidic, varying between 3.5-4.5; an increase in vaginal pH (5.0 to 6.5) can be associated with colonization by pathogenic microorganisms. The main goal of this study was to select an antimicrobial culture to be used in the prevention of vaginal colonization of Listeria monocytogenes during pregnancy, and consequently, prevent neonatal listeriosis. The survival and biofilm formation of 20 isolates of L. monocytogenes in simulated vaginal fluid at normal vaginal pH (4.2) and at higher pH values (5.5 and 6.5) was investigated. This pathogen was inhibited by the normal vaginal pH but survives when pH increases. All isolates tested were biofilm producers at different pH values. Streptococcus agalactiae is an important cause of neonatal infection and maternal colonization. Therefore, its behavior in simulated vaginal fluid was also analyzed. As with L. monocytogenes, S. agalactiae (n=10) survived longer at higher pH values than at normal vaginal pH. All S. agalactiae isolates were also biofilm producers. Therefore, since L. monocytogenes and S. agalactiae can survive at higher vaginal pHs, fetuses/neonates from women having increased vaginal pH values during pregnancy, may be at higher risk of neonatal infection. Biofilm production increases the probability of occurrence of neonatal infection. The application of vaginal probiotics could have the potential for preventing vaginal Listeria colonization in pregnant women and consequently reduce neonatal infections. Thirty-five isolates of Pediococcus spp. showed antimicrobial activity against L. monocytogenes, by production of a bacteriocin, but did not inhibit S. agalactiae isolates. Pediococcus spp. isolates demonstrated the ability to survive in simulated vaginal fluid at pH 4.2. Based on the higher bacteriocinogenic activity and survival in simulated vaginal fluid, one isolate of Pediococcus spp. was selected and characterized to evaluate its safety before use as vaginal probiotic. Pediococcus pentosaceus SB83 did not show the presence of virulence factors such as the production of gelatinase, lipase and DNase, hemolytic activity, nor the presence of virulence genes (i.e. surface adhesin, aggregation protein, cytolysin and extracellular metallo-endopeptidase). No relevant antibiotic resistance traits were detected. Pediococcus pentosaceus SB83 produced biofilms at different pH values (4.2, 5.5 and 6.5) in simulated vaginal fluid, which could also serve as a protective layer against colonization by pathogenic bacteria. The bacteriocin produced by P. pentosaceus SB83, designated as bacteriocin SB83, also showed inhibitory activity against Enterococcus faecalis and Enterococcus faecium, but did not inhibit vaginal lactic acid bacteria. Bacteriocin SB83 is resistant to several conditions, including conditions in the vaginal tract (pH and components of vaginal fluid). The bacteriocinogenic activity of P. pentosaceus SB83 against L. monocytogenes was evaluated in simulated vaginal fluid at pH 6.5, since this is the ideal pH to the L. monocytogenes survival and proliferation. There the inhibitory effect of the bacteriocinogenic culture was assessed in suspension, as lyophilized powder and in tablets. Suspensions of P. pentosaceus SB83 (1010 CFU/mL) reduced the pathogen (10 CFU/mL) 5after only 2 h of exposure to below the detection limit; the lyophilized bacteria after 24 h of contact and in tablet form, P. pentosaceus SB83 lost the antimicrobial activity. The pH of simulated vaginal fluid decreased in all the tested conditions. Since P. pentosaceus SB83 lose its antimicrobial activity in tablet form, it could be therefore used in the form of lyophilized powder, which may be administered intra-vaginally, for instance as a washing solution. This formulation was selected to evaluate the anti-listerial activity during 12 months of storage. During storage at room temperature, lyophilized bacteria totally inhibited the pathogen (below the detection limit) only during one month; after this time, there was a decrease in the cell counts of P.pentosaceus SB83 and, consequently, in antimicrobial potential. During storage at 4 ºC, P. pentosaceus SB83 showed antimicrobial activity throughout the time of storage investigated. The bacteriocin produced by P. pentosaceus SB83 after storage at 4 ºC, remained active at least during 12 months, however a slight decrease in antimicrobial activity occurred between 9 to 12 months. Therefore, the best formulation of P. pentosaceus SB83 is as a lyophilized powder stored at 4 ºC. These in vitro results prove a concept for the use of P. pentosaceus SB83 as a vaginal probiotic, to prevent vaginal colonization by L. monocytogenes in pregnant women.Os compostos antimicrobianos produzidos pelas bactérias do ácido láctico são importantes para a diminuição da colonização vaginal por agentes patogénicos. O pH vaginal é normalmente acídico, variando entre 3,5-4,5; um aumento do pH vaginal (5,0 a 6,5) pode ser associado à colonização por microrganismos patogénicos. O objetivo principal deste estudo foi selecionar uma cultura com propriedades antimicrobianas com potencial para utilização na prevenção da colonização vaginal por Listeria monocytogenes durante a gravidez e, consequentemente, evitar a listeriose neonatal. Foi investigada a sobrevivência e a capacidade de formação de biofilmes para 20 isolados de L. monocytogenes em fluido vaginal simulado a pH vaginal normal (4,2) e a valores de pH elevados (5,5 e 6,5). Este patogénico foi inibido em condições de pH vaginal normal, mas sobreviveu quando este aumentou. Todos os isolados testados formaram biofilme aos diferentes valores de pH. Streptococcus agalactiae, é um importante agente de colonização maternal e causa de infeção neonatal. Por este motivo, foi também analisado o seu comportamento em condições de simulação de fluido vaginal. Tal como L. monocytogenes, os isolados de S. agalactiae (n=10) sobreviveram melhor a valores de pH elevados comparativamente ao pH vaginal normal. Todos os isolados foram também produtores de biofilme. O facto de L. monocytogenes e S. agalactiae sobreviverem a valores de pH vaginal elevados, sugere que as mulheres grávidas que tenham um aumento do pH vaginal, podem ter um maior risco de infeção neonatal. A produção de biofilmes aumenta a probabilidade de ocorrência destas infeções. A aplicação vaginal de probióticos apresenta potencial para a prevenção de colonização vaginal por L. monocytogenes em mulheres grávidas e, consequentemente, reduzir as infeções neonatais. Trinta e cinco isolados de Pediococcus spp., demonstraram atividade antimicrobiana contra L. monocytogenes, pela produção de uma bacteriocina, no entanto, não apresentou atividade contra os isolados de S. agalactiae. Estes isolados de Pediococcus spp. sobreviveram no fluido vaginal simulado a pH 4,2. Com base nos resultados da avaliação da atividade bacteriocinogénica e sobrevivência em fluido vaginal simulado, Pediococcus pentosaceus SB83 foi selecionado para futura aplicação como probiótico vaginal. Pediococcus pentosaceus SB83 não demonstrou possuir fatores de virulência tais como produção de gelatinase, lipase e DNase, atividade hemolítica, nem possuiu os genes de virulência estudados (adesina de superfície, proteína de agregação, citolisina e metalo-endopeptidase extracelular). Não foram detetadas resistências a antibióticos. Pediococcus pentosaceus SB83 demonstrou ser produtor de biofilme em fluido vaginal simulado a diferentes valores de pH (4,2, 5,5 e 6,5), que também pode atuar como camada protetora contra a colonização por bactérias patogénicas. A bacteriocina produzida por P. pentosaceus SB83, designada por bacteriocina SB83, também demonstrou atividade inibitória contra Enterococcus faecalis e Enterococcus faecium, mas não apresentou efeito inibitório para bactérias do ácido láctico autóctones do trato vaginal. A bacteriocina SB83 demonstrou ser resistente a vários parâmetros, incluindo as condições do trato vaginal (pH e componentes do fluido vaginal). A atividade bacteriocinogénica de P. pentosaceus SB83 contra L. monocytogenes foi avaliada em fluido vaginal simulado a pH 6,5, pois este demonstrou ser o pH ideal para a sobrevivência e proliferação de L. monocytogenes. Foi testado o efeito inibitório da cultura bacteriocinogénica em suspensão, na forma liofilizada e em comprimidos. A suspensão bacteriana de P. pentosaceus SB83 (1010 UFC/mL) reduziu o patogénico (10 UFC/mL) em5 apenas 2 h (abaixo do limite de deteção), a bactéria liofilizada após 24 h de contacto e em comprimidos o P. pentosaceus SB83 perdeu a atividade antimicrobiana. O pH do fluido vaginal simulado diminuiu para todas as condições testadas. Como P. pentosaceus SB83 perdeu a atividade antimicrobiana quando na forma de comprimido, poderá ser utilizado na forma liofilizada, a qual pode ser administrada intravaginalmente, por exemplo como uma solução de lavagem. Esta formulação foi a selecionada para avaliar a atividade anti-listerial durante 12 meses de armazenamento. Durante o armazenamento à temperatura ambiente, a bactéria liofilizada inibiu totalmente o patogénico (abaixo do limite de detecção) apenas durante um mês; após este período de tempo, houve uma diminuição SB83 e, consequentemente, o potencial antimicrobiano. Durante o armazenamento a 4 ºC, P. pentosaceus SB83 apresentou atividade antimicrobiana durante todo o tempo de armazenamento investigado. A bacteriocina produzida por P. pentosaceus SB83 após o armazenamento a 4 ºC, manteve-se ativa pelo menos durante 12 meses, no entanto, uma ligeira diminuição na atividade antimicrobiana ocorreu entre os 9 e 12 meses. Portanto, a melhor formulação de P. pentosaceus SB83 é como liofilizado armazenado a 4 ºC. Estes resultados in vitro provam o conceito para a utilização de P. pentosaceus SB83 como probiótico vaginal, para prevenir a colonização vaginal por L. monocytogenes em mulheres grávidas

Effect of different conditions of growth and storage on the cell counts of two lactic acid bacteria after spray drying in orange juice

Consumers increasingly require innovative food products with health benefits. Thus, a dried orange juice incorporating probiotics could be a novel challenge. In this context, we investigated whether different sugars added to the culture media used for growth of two lactic acid bacteria contributed to their protection during spray drying in orange juice and subsequent storage under different conditions of temperature, light exposure and water activity. Cell viability during passage through simulated gastro-intestinal conditions was also investigated. Cells grown in culture medium containing fructose resulted in the worst survival rates during storage. High survival was observed for cells grown in the presence of lactose, followed by glucose. The survival of dried bacteria was enhanced at 4 C, water activity of 0.03 and absence of daylight. For cells grown in standard culture medium and after 12 months of storage at 4 C in orange juice powder (about 109 cfu/mL), there was a reduction of approximately 2 log-units for both lactic acid bacteria after gastro-intestinal tract passage simulation. Using the conditions of growth and storage investigated, it is possible to improve the survival rate of lactic acid bacteria and produce an orange juice powder with probiotic characteristics with shelf life of at least 12 months.info:eu-repo/semantics/publishedVersio

Functional role of macrobenthos in estuarine sediment dynamics

Thesis submitted to the Universidade Nova de Lisboa,Faculdade de Ciências e Tecnologia for the degree of Doctor of Philosophy in Environmental EngineeringEstuaries are areas of high sediment dynamics. Particles in suspension are an important vehicle of several biochemical substances and contaminants. Therefore, the knowledge on the processes ruling sediment dynamics is needed to develop tools for estuarine water quality management. Presently, few numerical models for sediment dynamics incorporate biological interactions with sediment dynamics. The aim of this study is to gain understanding of the macrobenthic influences on cohesive sediment dynamics. The research was focused on the effects of two species of macrobenthos; 1) the cockle Cerastoderma edule (densities of 280 to 1000 ind m-2). Work on this species focused on sediment transport and deposition, by studying the hydrodynamic effect on the sediment removal activity (filtration) and its effects on topography and on the current velocities at the boundary layer 2) The ragworm Nereis diversicolor (densities of 320 to 1200 ind m-2). This work focused on sediment erodability and consolidation by studying the bioturbation effect on changes in the sediment properties,and 3) the effect of contamination (3 nmol Cu g-1 dw) on the bioturbation activity of N. diversicolor and on sediment dynamics. The results from experiments performed in a racetrack and in an annular flume showed that increasing density of C. edule is proportional to increasing sediment topography and related to reduced current velocities near the bed and increased shear velocity (u*), hydrodynamic roughness length and turbulence kinetic energy (TKE). The higher TKE values were related to the presence of active filtering C. edule, producing additional turbulence to the TKE produced by topography. The effect of filtration activity on turbulence is most pronounced at low velocities (u* < 1.5 cm s-1), in agreement with a unimodal response to increased velocities. Increasing densities of N. diversicolor are related to increased sediment shear strength (SS), increased biodiffusion coefficients (Db) and increased erosion rates (ER). This antagonistic effect of increase SS and ER is explained by erosion of bigger aggregates resulting from biological bound sediments. This study provides some evidence that copper contaminated sediments are more stable, as a consequence of decrease in biological response to toxicity, observed in lower values of shear strength and erosion rates. In addition, new methodologies for the determination of some of the parametersinvolved with this research field are suggested.This thesis was financed by Fundação para a Ciência e Tecnologia SFRH/BD/6188/200

Enzymatic hydrolysis of insect Alphitobius diaperinus towards the development of bioactive peptide hydrolysates

Edible insects are a promising protein source for the future generation, due to their nutritional composition, sustainability and low environmental impact. Recent studies demonstrated their potential as a protein base to obtain bioactive peptides with potential applicability in the food industry. The aim of this study was to hydrolyze and analyze the potential of the edible insect Alphitobius diaperinus protein to develop an improved insect food ingredient with bioactive properties. After evaluating various conditions for the enzymatic hydrolysis with Alcalase 2.5L and Corolase PP, the best condition chosen for each enzyme was an enzyme : substrate ratio of 1.5% for 4 hours and a ratio of 3.0% for 6 hours, respectively. Insect protein hydrolysates are demonstrated to have relevant bioactive properties, namely antioxidant (by ABTS and ORAC methods) and antihypertensive activities (through the ability to inhibit the angiotensin converting enzyme, ACE), but no antimicrobial or antidiabetic properties were observed. Antioxidant activity values for hydrolysates obtained with Alcalase 2.5L and Corolase PP were 95.0 ± 0.8 and 95.7 ± 1.0 μmol Trolox equivalent per g insect powder by the ABTS method, 825.6 ± 85.5 and 944.8 ± 68.1 μmol Trolox equivalent per g insect powder by the ORAC method, respectively. Insect hydrolysates were able to inhibit the ACE and IC50 values for insect hydrolysates obtained with Alcalase 2.5L and Corolase PP were 55.5 ± 6.2 and 107.4 ± 9.7 μg of protein per mL, respectively. These insect protein hydrolysates can be used as a supplement/ingredient in the food industry with potential health benefits.N/

A bioethical perspective on the meanings behind a wish to hasten death: a meta-ethnographic review

info:eu-repo/semantics/publishedVersio

Síndrome de Gilles de La Tourette: Relato de Caso com Diagnóstico Tardio

Gilles de la Tourette syndrome is a neuropsychiatric disease that affects about 1% of the population with frequent onset during childhood or early adolescence. Tics, the central manifestation, tend to decrease in frequency and severity throughout adolescence, even though a small percentage of cases progress to severe illness. We present a clinical case description of a 28‑year‑old patient late diagnosed at 18 years old, with severe disease and no response to treatment as well as a prognostic and maintenance factor exploration and surgical indication in pharmacological resistant cases. The pathophysiology is not well established and there is no approved treatment for all patients. There are alternatives when psychotropic drugs are not effective and a surgical intervention is considered in this case. We highlight the importance of a good co‑work and communication between Child and Adolescent Psychiatry, Psychiatry and Primary Care and early diagnosis. Further studies and evidence will be necessary to define and individualize resistant cases treatment.A síndrome de Gilles de La Tourette é uma doença neuropsiquiátrica que afeta cerca de 1% da população. Tem início frequente na infância ou adolescência precoce. Os tiques, manifestação central, tendem a diminuir em frequência e gravidade durante a adolescência, existindo uma pequena percentagem de casos que evolui para doença grave. A propósito de um caso clínico de uma doente com 28 anos, com diagnóstico tardio aos 18 anos, doença grave e sem resposta ao tratamento, apresenta‑se uma revisão de fatores de prognóstico, manutenção e indicações para alternativa cirúrgica na doença resistente. A fisiopatologia não está definida, não existindo tratamento eficaz comprovada para estes indivíduos. Existem alternativas quando o tratamento com psicofármacos não é eficaz e considera‑se proposta cirúrgica neste caso. Destaca‑se a importância de uma boa articulação entre a Psiquiatria da Infância e Adolescência, a Psiquiatria e os Cuidados Primários. Conclui‑se que serão necessários mais estudos para definir e individualizar o tratamento em casos de doença resistente

Estágio de tradução na ABC Traduções: tradução jurídica

Mestrado em Tradução Especializada (Ciências Jurídicas)O presente relatório de estágio realizado na ABC Traduções, no âmbito da Tradução Jurídica, inclui a apresentação da empresa e a descrição das tarefas realizadas no âmbito do estágio curricular. Neste relatório descreve-se e analisa-se, ainda, o perfil do tradutor e a importância do domínio das ferramentas de apoio à tradução. Esta análise é complementada com a apresentação dos resultados de um inquérito a tradutores relativo ao perfil do tradutor, às suas competências e à sua opinião sobre a utilidade e a necessidade das ferramentas de apoio à tradução no século XXI.This final report on the Legal Translation Internship at ABC Traduções includes the presentation of the translation agency and a description of the tasks carried out during the curricular internship. In this report the profile of translators and the importance of the mastery of CAT tools is described and analyzed. This analysis is furthered with the presentation of the results of a translators’ questionnaire regarding the translators’ profile and competences and their opinions regarding the need and use of CAT tools in the 21st century

Metagenome-assembled genome sequences of three uncultured planktomarina sp. strains from the Northeast Atlantic Ocean

We report three metagenome-assembled genomes (MAGs) of Planktomarina strains from coastal seawater (Portugal) to help illuminate the functions of understudied Rhodobacteraceae bacteria in marine environments. The MAGs encode proteins involved in aerobic anoxygenic photosynthesis and a versatile carbohydrate metabolism, strengthening the role of Planktomarina species in oceanic carbon cycling.Portuguese Foundation for Science and Technology: EXPL/MAR-EST/1664/2013 PTDC/MAR-BIO/1547/2014, UIDB/04565/2020, PD/BD/143029/2018, CEECIND/00788/2017,PTDC/BIA-MIC/31996/2017;Institute of Bioengineering and Biosciences (iBB) by the Programa Operacional Regional de Lisboa 007317; Helmholtz Association VH-NG-1248.info:eu-repo/semantics/publishedVersio

New hydrogel biomaterial for the treatment of diabetic ulcers

info:eu-repo/semantics/publishedVersio

Black soldier fly: a new perspective as a functional and sustainable ingredient

The world population has been expected by the Food and Agriculture Organization ( of the United Nations to rise to over 9 billion by 2050 requiring an intensification in food production While the increase in human population efforts the demand for food, there is a concomitant decrease in accessible land resources needed to produce this food, which is likely to be exacerbated by global warming (Lange and Nakamura, 2021 The production and use of edible insects has arisen as one of the most fascinating alternative sources of proteins Insect rearing has several advantages related to environmental sustainability comparing to cattle raising, namely insects emit less greenhouse gases, require less land and water and present high feed conversion efficiency Insects are a highly nutritious source of food, with high protein, fat, vitamin, mineral and fiber content The nutritional profile of edible insects depends on the species and can be highly variable (Borges et al 2023 Lange and Nakamura, 2021 Hermetia illucens designated as black soldier fly ( is attractive as a food/feed because is a non infesting species contrary to Musca domestica (i e common fly) BSF larvae ( are avid consumers of decomposing organic matter and able to convert efficiently huge amounts of waste or spoiled food into biomass As for its chemical components, BSF prepupa is composed to 37 g/ 100 g lipids, 32 g/ 100 g proteins, 19 g/ 100 g mineral salts (including micronutrients, such as iron and zinc), and 9 g/ 100 g chitin (Montevecchi et al 2021 BSFL are a well recognized nutritious source with a high protein content In this context, enzymatic hydrolysis can be a promising process for the development of new insect based ingredients with improved bioactive properties This approach is widely used as a way to obtain bioactive peptides from various food matrices such soy protein milk protein, fish protein, egg white protein, among others Therefore, this work aimed to evaluate the potential of BSFL to generate bioactive peptides via enzymatic hydrolysis, with antioxidant and anti hypertensive potentialinfo:eu-repo/semantics/publishedVersio