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Edible insects are a potential alternative food source of high feed conversion efficiency and protein content. Zophobas atratus is an edible insect that adapts to different diets, enabling sustainable rearing by adding value to by-products and agro-industrial residues. This study aimed to evaluate the performance and nutritional characterization of Zophobas atratus larvae fed with different proportions of grape residue. Physicochemical analysis of the diets and larvae (AOAC procedures), fatty acid profile (chromatographic techniques), metals and non-metals (inductively coupled plasma optical emission spectrometry), larval mass gain, feed conversion efficiency, and mortality rate were assessed. The replacement of 25% of the conventional diet with grape residue increased lipid, ash, and fiber contents and reduced protein, carbohydrates, and energy. It promoted greater mass gain, lower mortality rate, and reduced larval growth time by 51%. Among the replacements, 25% resulted in the second-highest content of calcium, sodium, magnesium, and zinc, and the lowest content of potassium and phosphorus in the larvae. The 100% replacement resulted in the highest amounts of C18:2n6 (27.8%), C18:3n3 (2.2%), and PUFA (30.0%). Replacing 25% of the conventional diet with grape residue is equivalent to the conventional diet in many aspects and improves several larvae performance indices and nutritional values.
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Cálcio , Besouros , Animais , Larva , Cálcio/metabolismo , Magnésio/metabolismo , Besouros/metabolismo , Ração Animal/análise , Ácidos Graxos/metabolismo , Fósforo/metabolismo , Carboidratos , Zinco/metabolismo , Sódio/metabolismo , Potássio/metabolismoRESUMO
The aim of this study was to characterize and determine how days in milk (DIM) affect the milk fatty acid (FA) profile of grazing donkeys. Donkey milk is very similar to human milk, containing bioactive molecules such as FA and proteins. However, there is a lack of scientific and technical information on the changes in the FA profile of asinine milk in pasture-feeding systems. Seven multiparous Pega donkeys, maintained in an exclusively extensive system, were used. Milking was undertaken twice a day, once a week for 16 weeks. Milk samples were composed according to the average lactating days as follows: 55, 110, 165, 220 and 275 DIM. A descriptive analysis of the milk fat composition was performed, and the linear and quadratic effects of DIM on the milk FA profile were tested. The milk FA profile of grazing donkeys is influenced by lactation days and is characterized by high concentrations of polyunsaturated FA (PUFA) with a low n-6 to n-3 ratio (0.66 g/100 g), mainly due to the high level of linolenic acid (16.8 g/100 g). Most of the individual FAs did not change during lactation, but stearic and oleic acid linearly decreased (p < .05), and total polyunsaturated FA (PUFA) and n-3 FA increased (p < .05) with DIM. The milk profile of grazing donkeys is influenced by the day of lactation and is characterized by a high concentration of n-3 PUFA (mainly α-linolenic acid) and a lower n-6 to n-3 ratio. As the number of days of lactation increased, the concentration of n-3 PUFA also increased. Therefore, higher milk quality may be associated with higher days in milk.
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Lactação , Leite , Ração Animal/análise , Animais , Dieta/veterinária , Equidae , Ácidos Graxos , FemininoRESUMO
Mixed microbial cultures (MMC) and waste/surplus substrates, as hardwood spent sulfite liquor, are being used to decrease polyhydroxyalkanoates' (PHA) production costs. The process involves two or three steps, being the selection step a crucial one. For the industrial implementation of this strategy, reactor stability in terms of both performance and microbial community presence has to be considered. A long-term operation of a sequencing batch reactor under feast/famine conditions was performed along with microbial community identification/quantification using FISH and DGGE. The community was found to be extremely dynamic, dominated by Alphaproteobacteria, with Paracoccus and Rhodobacter present, both PHA-storing microorganisms. 16S rRNA gene clone library further revealed that side populations' non-PHA accumulators were able to strive (Agrobacterium, Flavobacteria, and Brachymonas). Nevertheless, reactor performance in terms of PHA storage was stable during operation time. The monitoring of the MMC population evolution provided information on the relation between community structure and process operation.
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Meios de Cultura/química , Microbiologia Industrial , Poli-Hidroxialcanoatos/biossíntese , Agrobacterium/isolamento & purificação , Agrobacterium/metabolismo , Alphaproteobacteria/isolamento & purificação , Alphaproteobacteria/metabolismo , Reatores Biológicos/microbiologia , Clonagem Molecular , Comamonadaceae/isolamento & purificação , Comamonadaceae/metabolismo , DNA Bacteriano/isolamento & purificação , Flavobacterium/isolamento & purificação , Flavobacterium/metabolismo , Biblioteca Gênica , Hibridização in Situ Fluorescente , Paracoccus/isolamento & purificação , Paracoccus/metabolismo , Filogenia , Poli-Hidroxialcanoatos/análise , Rhodobacter/isolamento & purificação , Rhodobacter/metabolismoRESUMO
Enrichment of mixed microbial cultures (MMCs) in polyhydroxyalkanoate (PHA)-storing microorganisms must take place to develop a successful PHA production process. Moreover, throughout the operational period of a MMC system, the population needs to be checked in order to understand the changes in the performance that eventually occurred. For these reasons, it is necessary to monitor the population evolution, in order to identify the different groups of microorganisms and relate them with the storage capacity and kinetics of the MMC. Regarding this particular process, several culture-independent molecular techniques were already applied, with the use of hybridization techniques such fluorescence in situ hybridization and also PCR-based methods like denaturing gradient gel electrophoresis, terminal restriction fragment length polymorphism, pyrosequencing, and quantitative PCR standing out. This review intends, thus, to look at the molecular methods currently applied in monitoring the PHA-storing population evolution and how they can be combined with the evolutionary engineering step in order to optimize the overall process.
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Bactérias/classificação , Bactérias/crescimento & desenvolvimento , Reatores Biológicos/microbiologia , Biotecnologia/métodos , Consórcios Microbianos , Poli-Hidroxialcanoatos/metabolismo , Bactérias/isolamento & purificação , Bactérias/metabolismo , Técnicas Bacteriológicas/métodos , Fermentação , Técnicas de Diagnóstico Molecular/métodosRESUMO
INTRODUCTION: Our department of anesthesiology has been conducting weekly, for several years, a group consultation to educate childbearing people about labor analgesia. The emergence of the COVID-19 pandemic forced an adaptation to a virtual consultation format. Since there are no studies about online group consultation on labor analgesia in order to understand its role, an anonymous questionnaire was created and applied. The objective was to evaluate this new consultation format, namely the ease of access, usefulness of the content provided, and its impact on the satisfaction and experience of childbirth. MATERIALS AND METHODS: An observational prospective study was conducted. A questionnaire was sent by e-mail after childbirth to all childbearing people participating in the online consultation from January 20, 2021, to March 2, 2022. SPSS Statistics version 28.0 (IBM Corp. Released 2021. IBM SPSS Statistics for Windows, Version 28.0. Armonk, NY: IBM Corp) was used for statistical analysis. Internal consistency was analyzed using Cronbach's alpha. RESULTS: A total of 563 participants were eligible, and 404 (71.8%) completed questionnaires were analyzed. A few technical problems were reported. The participants considered their privacy respected, and more than 90% were satisfied with the content of the online consultation, the opportunity to pose questions, and the help managing expectations. Considering face-to-face consultation, 89.6% of patients considered the online format an effective alternative, 63.2% believed it could replace the old model, and 96.3% would recommend it. CONCLUSIONS: Our study demonstrates that online consultation on labor analgesia was a good strategy during the COVID-19 pandemic and has the potential to be used in this format in the future.
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This work aimed to obtain and characterize chitin and chitosan extracted from the rearing residues of Tenebrio molitor, Zophobas morio, and Blaptica dubia insects in different growth stages in the same rearing cycles chitin and chitosan yielded 11.21 %-20.89 % and 6.26 %-7.07 %, respectively. The deacetylation degrees of chitosan ranged from 75.75 %-89.21 %, and the solubilities from 69.88 %-94.39 %. Infrared spectroscopy corroborated the acquisition of chitin and chitosan and can be used as a semi-quantitative technique for determining the degree of chitosan deacetylation. The X-ray diffraction profiles revealed the presence of α-chitin, and the relative crystalline indices ranged from 65.9 %-89.2 %. Typical TG profiles with two thermal events are observed for chitin and chitosan samples with different residue contents from the extraction procedure. The chitosan solutions exhibited pseudoplastic behavior, with apparent viscosities ranging from 195.96 to 249.86 mPa.s. The characterization results of the biopolymers extracted from insect residues were similar to those obtained from conventional sources. The growth stage influenced the chitin yield and crystallinity index. The results of this study reinforce the feasibility of using alternative sources of chitin and chitosan, providing the use of waste from insect farms and contributing to sustainability and a circular economy.
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Quitosana , Besouros , Animais , Quitosana/química , Quitina/química , Insetos , Besouros/química , Difração de Raios XRESUMO
This study aimed to encapsulate Talaromyces amestolkiae colorants in maltodextrin and chitosan microparticles using the spraydrying technique and to evaluate the biopolymers' capacities to protect the fungal colorant against temperature (65 °C) and extreme pH (2.0 and 13.0). The compact microparticles exhibited smooth or indented surfaces with internal diameters ranging between 2.58-4.69 µm and ζ ~ -26 mV. The encapsulation efficiencies were 86 % and 56 % for chitosan and maltodextrin microparticles, respectively. The shifted endothermic peaks of the free colorants indicated their physical stabilization into microparticles. The encapsulated colorants retained most of their absorbance (compared to the 0 h) even after 25 days at 65 °C. Contrary, the free colorant presented almost no absorbance after 1 day under the same conditions. Colorants in chitosan and maltodextrin matrices also partially maintained their colorimetric and fluorometric properties at acidic pH. However, only maltodextrin improved the resistance of the red colorant to alkaline environments. For the first time, the potential of polysaccharide-based microparticles to preserve polyketide colorants was demonstrated using 3D fluorescence. Therefore, this study demonstrated an alternative in developing functional products with natural color additives.
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Quitosana , Polissacarídeos , Quitosana/química , Polissacarídeos/química , Concentração de Íons de Hidrogênio , Corantes/química , Talaromyces/química , Tamanho da Partícula , Temperatura , MicroesferasRESUMO
INTRODUCTION: The dissemination of the COVID-19 pandemic in Europe, namely in Portugal, demanded an organizational and clinical reaction from the Portuguese National Health Service. With the unpredictable impact of COVID-19 infected patients redefining hospital logistics, reducing non-priority elective care and extending the hospital capacity for critical care patients made mobilizing a significant part of human resources a priority. We conducted a national survey to monitor the contribution and the role of anaesthesiologists belonging to the 53 Portuguese National Health Service hospitals in the first wave fight against the pandemic. MATERIAL AND METHODS: This prospective cross-sectional observational study used a weekly survey sent to the Directors of the Anaesthesiology Departments of all Portuguese National Health Service hospitals, between the period of 13th April and 21st June 2020. Directors were asked about human resources, hospital logistics, anaesthetic activity and residency programs in their departments as well as contingency plans facing the impact of the pandemic growth in the PNHS. RESULTS: Contingency strategy for all Portuguese National Health Service hospitals planned for a total of 1524 level III critical care beds during the initial phases of the pandemic, an increase of 151% from the existing 607 level III critical care beds in Portugal in January 2020. This re-configuration effort of the Portuguese National Health Service was only possible due to the partial or total suspension of non-urgent elective activity that reached over 90% of these institutions in the first pandemic months (March and April) and the deployment of anaesthesiologists from their normal activities to the treatment of critical care patients. During the peak of the first pandemic wave, 209 anaesthesiology specialists and 170 trainees (22.9% of the total anaesthesiologist's staff in the Portuguese National Health Service) were deployed in critical care. There was an almost complete interruption of the residency program rotation in 70.4% of hospitals with anaesthesiology residents, between March and April 2020. CONCLUSION: During the first pandemic wave there was an effective and fast reorganisation of the Portuguese National Health Service in order to increase level III critical care beds, which might have contributed to the low mortality rates in Portugal. We believe that this could have also been a result of the contribution given by all public anaesthesiology departments.
Introdução: A disseminação da pandemia por COVID-19 na Europa, designadamente em Portugal, exigiu uma resposta clínica e organizativa por parte do Serviço Nacional de Saúde português. Com o imprevisível impacto da COVID-19 nos doentes infectados, foi prioritário redefinir a logística hospitalar, reduzir a prestação de cuidados electivos não prioritários, e estender a capacidade hospitalar ao tratamento do doente crítico, mobilizando uma parte significativa dos recursos humanos. Utilizou-se um inquérito nacional que permitisse monitorizar a contribuição que os anestesiologistas pertencentes aos 53 hospitais do Serviço Nacional de Saúde tiveram no combate à COVID-19 durante a primeira vaga da pandemia. Material e Métodos: Estudo observacional transversal de tipo prospectivo, baseado num inquérito semanal enviado aos directores dos Serviços de Anestesiologia de todos os hospitais do Serviço Nacional de Saúde, entre 13 de abril e 21 de junho de 2020. Foi solicitada informação relativa aos recursos humanos, logística hospitalar, atividade assistencial, programa de formação pós-graduado, assim como plano de contingência face ao crescimento da pandemia. Resultados: O plano de contingência hospitalar nos hospitais do Serviço Nacional de Saúde previu um total de 1524 camas de cuidados intensivos de nível III, o que corresponde a um crescimento de 151% das 607 camas existentes em janeiro de 2020. Esta reconfiguração dos hospitais do Serviço Nacional de Saúde só foi possível devido à suspensão parcial ou total da atividade eletiva não prioritária que afectou mais de 90% das instituições hospitalares nos primeiros meses da pandemia (março e abril), e à mobilização dos anestesiologistas das suas atividades eletivas para o tratamento do doente crítico. Nos piores momentos, esta mobilização envolveu 209 especialistas e 170 internos de especialidade (22,9% do total destes profissionais nos hospitais do Serviço Nacional de Saúde). Por outro lado, registou-se uma interrupção quase total do programa de formação pós-graduada em mais de 70,4% dos hospitais com esta idoneidade formativa, de março a abril de 2020. Conclusão: Durante a primeira vaga da pandemia houve uma rápida reorganização do Serviço Nacional de Saúde que poderá ter contribuído para a baixa taxa de mortalidade em Portugal. Os autores acreditam que para esse resultado poderá ainda ter contribuído a ajuda dada pelos serviços de Anestesiologia do Serviço Nacional de Saúde.
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Anestesiologia , COVID-19 , Humanos , COVID-19/epidemiologia , Pandemias , Portugal/epidemiologia , Medicina Estatal , Estudos Transversais , Estudos ProspectivosRESUMO
This work aimed to evaluate the properties of butylene adipate-co-terephthalate (PBAT) degraded after 1800 days of storage (DPBAT) by preparing blends (films) with crosslinked starch (Cm) through extrusion and thermocompression. Different ratios of DPBAT:Cm (70:30, 60:40, and 50:50 m/m) were prepared. The incorporation of Cm into DPBAT significantly changed the properties of the films by making them stiffer (increasing Young's modulus by up to 50%) and increasing the thermal resistance of DPBAT. The presence of crosslinked starch in the films made them less hydrophobic (with decreased contact angle and increased moisture content), but these parameters did not vary linearly with changes in the content of crosslinked starch in the blend (DPBAT:Cm). The microscopic images show an inhomogeneous distribution of Cm granules in the DPBAT matrix. Thus, the films prepared with PBAT show a significant decrease in their mechanical parameters and heat resistance after long-term storage. However, the preparation of blends of degraded DPBAT with crosslinked starch promoted changes in the properties of the films prepared by thermocompression, which could be useful for disposable packaging.
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Acidogenic fermentation (AF) is often applied to wastes to produce short-chain organic acids (SCOAs)-molecules with applications in many industries. Spent coffee grounds (SCGs) are a residue from the coffee industry that is rich in carbohydrates, having the potential to be valorized by this process. However, given the recalcitrant nature of this waste, the addition of a pretreatment step can significantly improve AF. In this work, several pretreatment strategies were applied to SCGs (acidic hydrolysis, basic hydrolysis, hydrothermal, microwave, ultrasounds, and supercritical CO2 extraction), evaluated in terms of sugar and inhibitors release, and used in AF. Despite the low yields of sugar extracted, almost all pretreatments increased SCOAs production. Milder extraction conditions also resulted in lower concentrations of inhibitory compounds and, consequently, in a higher concentration of SCOAs. The best results were obtained with acidic hydrolysis of 5%, leading to a production of 1.33 gSCOAs/L, an increase of 185% compared with untreated SCGs.
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Spent coffee grounds (SCGs) are a promising substrate that can be valorized by biotechnological processes, such as for short-chain organic acid (SCOA) production, but their complex structure implies the application of a pretreatment step to increase their biodegradability. Physicochemical pretreatments are widely studied but have multiple drawbacks. An alternative is the application of biological pretreatments that include using fungi Trametes versicolor and Paecilomyces variotii that naturally can degrade complex substrates such as SCGs. This study intended to compare acidic and basic hydrolysis and supercritical CO2 extraction with the application of these fungi. The highest concentration of SCOAs, 2.52 gCOD/L, was achieved after the acidification of SCGs pretreated with acid hydrolysis, but a very similar result, 2.44 gCOD/L, was obtained after submerged fermentation of SCGs by T. versicolor. This pretreatment also resulted in the best acidification degree, 48%, a very promising result compared to the 13% obtained with the control, untreated SCGs, highlighting the potential of biological pretreatments.
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Café , Trametes , Dióxido de Carbono/metabolismo , Café/química , Fermentação , Hidrólise , Trametes/metabolismoRESUMO
Two eco-friendly healing bioproducts generated from microbial mixed cultures (MMC) for the production of polyhydroxyalkanoates (PHA) were used as surface treatments, with two residual materials used as the substrates, namely crude glycerol and pinewood bio-oil. Their ability to improve the durability of concrete samples containing recycled aggregates was assessed. To determine this protective capacity, 180 samples were analyzed using different tests, such as water penetration under pressure, capillary absorption, freeze-thaw and water droplet absorption test. Three types of conditions were used: outdoor-indoor exposure, re-application of biopolymers and application in vertical exposure conditions. The results showed reductions of up to 50% in the water penetration test and a delay in the water droplet absorption test of up to 150 times relative to the reference. The surface application of these bioproducts significantly reduced the degree of water penetration in recycled concrete, increasing its useful lifespan and proving to be a promising treatment for protecting concrete surfaces.
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[S,S]-ethylenediamine-N,N'-diglutaric acid (EDDG) has been gaining interest in the industrial sector as a promising chelator. In this study, the effective metal complexing capacity of EDDG over a wide pH range was modelled and its biodegradability assessed. Results showed that EDDG could effectively bind to several metallic ions in a wide pH range and was completely biodegraded after approximately 15 days by un-acclimatized sludge. To confirm its biodegradability, an accurate quantification method based on the combination of liquid chromatography and tandem quadrupole mass spectrometry (LC-MS/MS) was developed. Good linearity of the detector response was found for EDDG at concentrations ranging from 0.15 to 1.2 mg/L.
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Quelantes/metabolismo , Ácido Glutâmico/análogos & derivados , Metais/metabolismo , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Quelantes/análise , Quelantes/química , Ácido Glutâmico/análise , Ácido Glutâmico/química , Ácido Glutâmico/metabolismo , Metais/análise , Metais/química , Modelos Químicos , Esgotos/química , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/químicaRESUMO
Fluorescence in situ hybridization (FISH) enables the detection and enumeration of microorganisms in a diversity of samples. Short-length oligonucleotide DNA probes complementary to 16S or 23S rRNA sequences are generally used to target different phylogenetic levels. The protocol for the application of FISH to aggregated or suspended cells in mixed microbial communities is described in this chapter, with a special emphasis on environmental samples.
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Hibridização in Situ Fluorescente/métodos , Microbiota/genética , Sondas de Oligonucleotídeos/genética , Filogenia , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genéticaRESUMO
Starch derivatives are versatile compounds that are widely used in the pharmaceutical industry. This article reviews the advances in the research on hydrophilic and hydrophobic starch derivatives used to develop drug delivery systems over the last ten years, specifically microparticles, nanoparticles, nanocrystals, hydrogels, and scaffolds using these materials. The fundamentals of drug delivery systems, regulatory aspects, and chemical modifications are also discussed, along with the synthesis of starch derivatives via oxidation, etherification, acid hydrolysis, esterification, and cross-linking. The chemical modification of starch as a means to overcome the challenges in obtaining solid dosage forms is also reviewed. In particular, dialdehyde starches are potential derivatives for direct drug attachment; carboxymethyl starches are used for drug encapsulation and release, giving rise to pH-sensitive devices through electrostatic interactions; and starch nanocrystals have high potential as hydrogel fillers to improve mechanical properties and control drug release through hydrophilic interactions. Starch esterification with alginate and acidic drugs could be very useful for site-specific, controlled release. Starch cross-linking with other biopolymers such as xanthan gum is promising for obtaining novel polyelectrolyte hydrogels with improved functional properties. Surface modification of starch nanoparticles by cross-linking and esterification reactions is a potential approach to obtain novel, smart solid dosages.
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Aprovação de Drogas/organização & administração , Sistemas de Liberação de Medicamentos/métodos , Amido/química , Reagentes de Ligações Cruzadas/química , Esterificação , Legislação de Medicamentos , Estados Unidos , United States Food and Drug AdministrationRESUMO
Background: SARS-CoV-2 virus changed society's behaviour. Population was advised to reduce unnecessary heath care use to accommodate urgent cases and daily increase of COVID-19 patients. Health care facilities faced huge challenges, having to readjust their response to preserve good quality of care. In Portugal, a significant reduction in the number of admissions to the Emergency Department (ED) was reported all over the country, however the impact on the dynamics of undeferrable surgery remains to be reported. This study compares the volume and characteristics of urgent/emergency surgery during the 2020 COVID-19 pandemic with the homologous period in 2019, chronologically illustrating the national evolution of new COVID-19 cases and the social and hospital containment response. Methods: A retrospective observational study was conducted in a tertiary hospital center located in the most affected region by COVID-19 in Portugal. Medical records of patients who underwent urgent/emergency surgery between March 1st and May 2nd of both 2020 and 2019 were examined and the volume of surgeries were compared. Also, daily national updates from Portuguese Directorate-General for Health were analysed. Results: During the COVID-19 pandemic approximately 30% less patients underwent urgent/emergency surgery (99%CI = 0.18-0.61, p < 0.001). Waiting time for surgery showed no difference between both years (p = 0.068), but patients who did surgery during the 2020 pandemic had higher mortality rates than the ones who did it in 2019 (11.4% in 2020 and 5.9% in 2019, p = 0.001). Reduction in surgery volume was correlated with the increasing number of infected cases nationally. Conclusion: This study demonstrates decreasing numbers of urgent/emergency procedures during the COVID-19 pandemic that may be justified by the national growth number of infected cases. Preoperative mass screening strategy was implemented without compromising the efficiency of surgical service, but patients' mortality was higher. The importance of visiting the ED during COVID-19 pandemic for serious cases that cannot be managed in other settings should be highlighted.
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COVID-19 , Emergências , Procedimentos Cirúrgicos Operatórios/estatística & dados numéricos , Idoso , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Portugal , Estudos Retrospectivos , Centros de Atenção Terciária , Listas de EsperaRESUMO
The large increase in the world population has resulted in a very large amount of construction waste, as well as a large amount of waste glycerol from transesterification reactions of acyl glycerides from oils and fats, in particular from the production of biodiesel. Only a limited percentage of these two residues are recycled, which generates a large management problem worldwide. For that reason, in this study, we used crude glycerol as a carbon source to cultivate polyhydroxyalkanoates (PHA)-producing mixed microbial cultures (MMC). Two bioproducts derived from these cultures were applied on the surface of concrete with recycled aggregate to create a protective layer. To evaluate the effect of the treatments, tests of water absorption by capillarity and under low pressure with Karsten tubes were performed. Furthermore, SEM-EDS analysis showed the physical barrier caused by biotreatments that produced a reduction on capillarity water absorption of up to 20% and improved the impermeability of recycled concrete against the penetration of water under pressure up to 2.7 times relative to the reference. Therefore, this bioproduct shown to be a promising treatment to protect against penetration of water to concrete surfaces increasing its durability and useful life.
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One approach to tackle the problems created by the vast amounts of construction and demolition waste (CDW) generated worldwide while at the same time lengthening concrete durability and service life is to foster the use of recycled aggregate (RA) rather than natural aggregate (NA). This article discusses the use of polyhydroxyalkanoates (PHAs)-producing mixed microbial cultures (MMCs) to treat the surface of recycled concrete with a view to increase its resistance to water-mediated deterioration. The microorganisms were cultured in a minimal medium using waste pinewood bio-oil as a carbon source. Post-application variations in substrate permeability were determined with the water drop absorption and penetration by water under pressure tests. The significant reduction in water absorption recorded reveals that this bioproduct is a promising surface treatment for recycled concrete.
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Pulp and paper factories produce several residues that can be explored and valorized through polyhydroxyalkanoate (PHA) production via a three-step process. The objective of this work was focused on the selection step. Acidified hardwood spent sulfite liquor (HSSL), a fermented waste stream from a pulp and paper factory, was used to select a mixed microbial culture (MMC) in a sequencing batch reactor (SBR) operated for 156 days under different operational conditions. The MMC adapted to the imposed conditions, revealing its robustness whenever the operational parameters were changed. Feast-to-Famine ratio was kept below or equal to 0.2, with constant production of a copolymer of P(3HB-co-3â¯HV), and with storage contents values over 30 %. Changes in the operational conditions, namely cycle length, and organic load rate (OLR), successfully led to the selection of an MMC with a stable accumulation capacity and an increased biomass concentration. Next Generation Sequencing analysis was performed on samples collected during the SBR operational period. The analysis of the microbial composition of the MMC showed a rise in PHA-accumulating bacteria over time. Acidovorax and Comamonas species were found mainly to drive the PHA storage process during the first two periods of operation. After an increase in the OLR, in the last period, a shift towards Comamonas dominance occurred, suggesting a higher tolerance to the inhibitory compounds of the HSSL for this genus.
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Comamonadaceae/metabolismo , Comamonas/metabolismo , Fermentação , Consórcios Microbianos , Bifenilos Policlorados/metabolismo , Sulfitos/metabolismo , Reatores BiológicosRESUMO
BACKGROUND AND OBJECTIVES: The gold standard for the treatment of postdural puncture headache (PDPH) is the epidural blood patch (EBP). Regional techniques-sphenopalatine ganglion block (SPGB), greater occipital nerve block (GONB) and trigger point infiltration (TPI)-can also be used for the treatment of PDPH. Our objective was to evaluate the efficacy of these peripheral nerve blocks (PNBs) in the treatment of PDPH. METHODS: A retrospective study was conducted including all patients with PDPH in the obstetrics department of our institution between April 2016 and December 2017. Data were retrieved from clinical records regarding anesthetic technique, symptoms, treatment, Numeric Pain Score (NPS) before and after treatment, among others. RESULTS: We observed 50 cases of PDPH: 25 following spinal anesthesia, 19 following epidural block and 6 following combined spinal-epidural. Of these, seven were managed conservatively and one received EBP as first-line treatment. The remaining 42 patients received PNB as first-line treatment. Of these, 27 received only 1 course of PNB, while 15 received 2 courses. We observed a statistically significant improvement in the NPS after the first course of blocks (n=42), with a reduction of the median NPS by 6.0 (IQR 4.0-7.5; p<0.001). Improvement was also observed after the second course of blocks (n=15), with a reduction of the median NPS of 3.5 (IQR 1.5-5.0; p=0.02). Due to treatment failure, 9 of the 42 patients treated with PNB required EBP. None of these were cases following spinal anesthesia. CONCLUSION: SPGB, GONB and TPI can be safe and effective options for treatment of PDPH, but do not completely eliminate the need for EBP. Prospective studies designed to identify factors associated with unsuccessful treatment are required.