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BACKGROUND: Curative treatment for gastric cancer involves tumor resection, followed by transit reconstruction, with Roux-en-Y being the main technique employed. To permit food transit to the duodenum, which is absent in Roux-en-Y, double transit reconstruction has been used, whose theoretical advantages seem to surpass the previous technique. AIMS: To compare the clinical evolution of gastric cancer patients who underwent total gastrectomy with Roux-en-Y and double tract reconstruction. METHODS: A systematic review was carried out on Web of Science, Scopus, EmbasE, SciELO, Virtual Health Library, PubMed, Cochrane, and Google Scholar databases. Data were collected until June 11, 2022. Observational studies or clinical trials evaluating patients submitted to double tract (DT) and Roux-en-Y (RY) reconstructions were included. There was no temporal or language restriction. Review articles, case reports, case series, and incomplete texts were excluded. The risk of bias was calculated using the Cochrane tool designed for randomized clinical trials. RESULTS: Four studies of good methodological quality were included, encompassing 209 participants. In the RY group, there was a greater reduction in food intake. In the DT group, the decrease in body mass index was less pronounced compared to preoperative values. CONCLUSIONS: The double tract reconstruction had better outcomes concerning body mass index and the time until starting a light diet; however, it did not present any advantages in relation to nutritional deficits, quality of life, and post-surgical complications.
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Anastomose em-Y de Roux , Gastrectomia , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirurgia , Gastrectomia/métodos , Anastomose em-Y de Roux/métodos , Trânsito Gastrointestinal/fisiologia , Procedimentos de Cirurgia Plástica/métodosRESUMO
ABSTRACT BACKGROUND: Curative treatment for gastric cancer involves tumor resection, followed by transit reconstruction, with Roux-en-Y being the main technique employed. To permit food transit to the duodenum, which is absent in Roux-en-Y, double transit reconstruction has been used, whose theoretical advantages seem to surpass the previous technique. AIMS: To compare the clinical evolution of gastric cancer patients who underwent total gastrectomy with Roux-en-Y and double tract reconstruction. METHODS: A systematic review was carried out on Web of Science, Scopus, EmbasE, SciELO, Virtual Health Library, PubMed, Cochrane, and Google Scholar databases. Data were collected until June 11, 2022. Observational studies or clinical trials evaluating patients submitted to double tract (DT) and Roux-en-Y (RY) reconstructions were included. There was no temporal or language restriction. Review articles, case reports, case series, and incomplete texts were excluded. The risk of bias was calculated using the Cochrane tool designed for randomized clinical trials. RESULTS: Four studies of good methodological quality were included, encompassing 209 participants. In the RY group, there was a greater reduction in food intake. In the DT group, the decrease in body mass index was less pronounced compared to preoperative values. CONCLUSIONS: The double tract reconstruction had better outcomes concerning body mass index and the time until starting a light diet; however, it did not present any advantages in relation to nutritional deficits, quality of life, and post-surgical complications.
RESUMO RACIONAL: O tratamento curativo do câncer gástrico envolve a ressecção do tumor, seguida de reconstrução do trânsito, sendo o Y-de-Roux a principal técnica empregada. Para permitir o trânsito alimentar para o duodeno, ausente em Y-de-Roux, tem-se utilizado a reconstrução de duplo trânsito, cujas vantagens teóricas parecem superar a técnica anterior. OBJETIVOS: Comparar a evolução clínica de pacientes com câncer gástrico submetidos à gastrectomia total com Y-de-Roux e reconstrução de duplo trânsito. MÉTODOS: Foi realizada uma revisão sistemática nas bases de dados: Web of Science, Scopus, Embase, Scielo, Biblioteca Virtual em Saúde, PubMed e Cochrane. Os dados foram coletados até 11 de junho de 2022. Foram incluídos estudos observacionais ou ensaios clínicos avaliando pacientes que utilizaram reconstruções de duplo trânsito (DT) e Y-de-Roux (RY). Não houve restrição temporal ou de idioma. Foram excluídos artigos de revisão, relatos de casos, séries de casos e aqueles com texto incompleto. O risco de viés foi calculado utilizando a ferramenta Cochrane desenvolvida para ensaios clínicos randomizados. RESULTADOS: Foram incluídos quatro estudos de boa qualidade metodológica, abrangendo 209 participantes. No grupo RY houve maior redução na ingestão alimentar. No grupo DT, a diminuição do índice de massa corporal (IMC) foi menos pronunciada em comparação aos valores pré-operatórios. CONCLUSÕES: A reconstrução de duplo trânsito apresentou melhores resultados em relação ao índice de massa corporal e ao tempo para início de dieta leve, porém não apresentou vantagens em relação aos déficits nutricionais, qualidade de vida e complicações pós-cirúrgicas.
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Phycoremediation of swine wastewater is a promising treatment since it efficiently removes nutrients and contaminants and, simultaneously, its biomass can be harvested and used to obtain a wide range of valuable compounds and metabolites. In this context, biomass microalgae were investigated for the phycoremediation of swine wastewater, and biomass extracts for its virucidal effect against enveloped and non-enveloped viruses. Microalgae were cultivated in a pilot scale bioreactor fed with swine wastewater as the growth substrate. Hexane, dichloromethane, and methanol were used to obtain the microalgae extracts. Extracts were tested for virucidal potential against HSV-1 and HAdV-5. Virucidal assays were conducted at temperatures that emulate environmental conditions (21 °C) and body temperature (37 °C). The maximum production of microalgae biomass reached a concentration of 318.5 ± 23.6 mgDW L-1. The results showed that phycoremediation removed 100% of ammonia-N and phosphate-P, with rates (k1) of 0.218 ± 0.013 and 0.501 ± 0.038 (day-1), respectively. All microalgae extract reduced 100% of the infectious capacity of HSV-1. The microalgae extracts with dichloromethane and methanol showed inhibition activities at the lowest concentration (3.125 µg mL-1). Virucidal assays against HAdV-5 using microalgae extract of hexane and methanol inhibited the infectious capacity of the virus by 70% at all concentrations tested at 37 °C. At a concentration of 12.5 µg mL-1, the dichloromethane microalgae extract reduced 50-80% of the infectious capacity of HAdV-5, also at 37 °C. Overall, the results suggest that the microalgae can be an attractive source of feedstock biomass for the exploration of alternative virucidal compounds.
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Chlorella , Microalgas , Animais , Biomassa , Hexanos , Metanol/metabolismo , Cloreto de Metileno , Microalgas/metabolismo , Nitrogênio/análise , Extratos Vegetais/metabolismo , Suínos , Águas ResiduáriasRESUMO
OBJECTIVE: To summarize the main evidence from educational interventions designed to increase levels of physical activity (PA) among Brazilian adults. METHODS: Systematic review of intervention studies carried out in Brazil that implemented educational components aimed at promoting increased levels of PA among adult populations (18 to 65 years old). In October 2020, systematic searches were conducted in six databases, and in the reference lists of the assessed studies. RESULTS: Of the initial 2,511 studies, nine were included in the synthesis. Samples with specific characteristics (such as social vulnerability, physical inactivity, and overweight or obesity) were observed, with a greater number of women. Five interventions (55.6%) occurred in primary healthcare settings (PHC) of the Brazilian Unified Health System (SUS). Only four studies (44.4%) described the pedagogical frameworks structuring the educational approaches, among which counseling was the most used strategy, such as those carried out through face-to-face meetings, home visits, lectures, and phone calls (n = 8; 88.9%). Positive results were observed in three different indicators: increase in weekly PA volume (n = 4); increase in leisure-time PA rate (n = 1); and increase in the proportion of women classified as "very active/active" (n = 1). Given the sampling specificities, the domain "participant selection" showed a high number of interventions with high risk of bias. CONCLUSIONS: Educational approaches engendered some positive effects on different PA indicators, notably counseling as the main strategy used and approaches involving other health themes, such as nutrition and stress. However, considering the several determinants of PA in Brazil, future interventions should be conducted in different locations of Brazil in order to evaluate, in a broader way, their implementation processes and articulation with the many professionals working in PHC.
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Exercício Físico , Vulnerabilidade Social , Adolescente , Adulto , Idoso , Brasil , Feminino , Humanos , Pessoa de Meia-Idade , Obesidade , Sobrepeso , Adulto JovemRESUMO
ABSTRACT OBJECTIVE To summarize the main evidence from educational interventions designed to increase levels of physical activity (PA) among Brazilian adults. METHODS Systematic review of intervention studies carried out in Brazil that implemented educational components aimed at promoting increased levels of PA among adult populations (18 to 65 years old). In October 2020, systematic searches were conducted in six databases, and in the reference lists of the assessed studies. RESULTS Of the initial 2,511 studies, nine were included in the synthesis. Samples with specific characteristics (such as social vulnerability, physical inactivity, and overweight or obesity) were observed, with a greater number of women. Five interventions (55.6%) occurred in primary healthcare settings (PHC) of the Brazilian Unified Health System (SUS). Only four studies (44.4%) described the pedagogical frameworks structuring the educational approaches, among which counseling was the most used strategy, such as those carried out through face-to-face meetings, home visits, lectures, and phone calls (n = 8; 88.9%). Positive results were observed in three different indicators: increase in weekly PA volume (n = 4); increase in leisure-time PA rate (n = 1); and increase in the proportion of women classified as "very active/active" (n = 1). Given the sampling specificities, the domain "participant selection" showed a high number of interventions with high risk of bias. CONCLUSIONS Educational approaches engendered some positive effects on different PA indicators, notably counseling as the main strategy used and approaches involving other health themes, such as nutrition and stress. However, considering the several determinants of PA in Brazil, future interventions should be conducted in different locations of Brazil in order to evaluate, in a broader way, their implementation processes and articulation with the many professionals working in PHC.
RESUMO OBJETIVO Sumarizar as principais evidências de intervenções educativas delineadas para o aumento dos níveis de atividade física (AF) em adultos brasileiros. MÉTODOS Revisão sistemática de estudos de intervenção conduzidos no Brasil, que implementaram componentes educativos com a finalidade de promover o aumento dos níveis de AF em populações de adultos (18 a 65 anos). Em outubro de 2020, buscas sistemáticas foram conduzidas em seis bases de dados e nas listas de referências dos artigos avaliados. RESULTADOS Dos 2.511 artigos iniciais, nove compuseram a síntese. Foram observadas amostras com características específicas (como vulnerabilidade social, inatividade física e sobrepeso ou obesidade), com maior número de mulheres. Cinco intervenções (55,6%) ocorreram nos cenários da atenção primária à saúde (APS) do Sistema Único de Saúde (SUS). Apenas em quatro estudos (44,4%) houve descrição dos referenciais pedagógicos estruturantes das abordagens educativas, dentro os quais o aconselhamento se configurou como a estratégia mais utilizada, como aquelas realizadas por meio de encontros presenciais, visitas domiciliares, palestras e chamadas telefônicas (n = 8; 88,9%). Resultados positivos foram observados em três distintos indicadores: aumento do volume semanal de AF (n = 4); aumento do índice de AF no lazer (n = 1); e aumento da proporção de mulheres classificadas como "muito ativas/ativas" (n = 1). Visto as especificidades amostrais, o domínio "seleção dos participantes" apresentou elevado número de intervenções com alto risco de viés. CONCLUSÕES As abordagens educativas produziram alguns efeitos positivos em distintos indicadores de AF, destacando-se o aconselhamento como principal estratégia utilizada e as abordagens que envolveram outras temáticas de saúde, como nutrição e estresse. Contudo, frente aos diversos determinantes da AF no Brasil, é importante que futuras intervenções sejam conduzidas em variadas localizações do país, de forma que avaliem, de maneira mais ampla, seus processos de implementação e articulação com os distintos profissionais que atuam na APS.
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Humanos , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Exercício Físico , Vulnerabilidade Social , Brasil , Sobrepeso , ObesidadeRESUMO
RESUMO O controle do crescimento microbiano é um desafio crescente na produção de petróleo e gás, uma vez que a presença de determinadas bactérias traz impactos econômica e ambientalmente negativos. As bactérias redutoras de sulfato (BRS) são particularmente problemáticas, uma vez que são responsáveis pela corrosão biológica ligada à produção de sulfeto de hidrogênio, efeito conhecido como souring. A principal forma de controle das BRS atualmente é a injeção de biocidas, no entanto essa estratégia, além de requerer aplicação contínua, tem se revelado pouco efetiva na eliminação de biofilmes e é associada a um alto risco de contaminação das águas. Portanto, é necessário que se busquem abordagens mais eficientes e específicas em relação ao controle microbiológico. O uso de vírus bacteriófagos vem ao encontro dessas necessidades, pois eles, após se multiplicarem, geralmente provocam a lise celular, liberando novas partículas virais e evitando que a bactéria se prolifere. Diante disso, este estudo propõe estabelecer um método para a concentração e a determinação da eficiência de recuperação de bacteriófagos de BRS presentes em água de reator oriunda de poços de petróleo. As amostras foram coletadas de dois reatores operados em batelada alimentada e que simulam um poço de petróleo. As amostras de água de reator foram primeiramente clarificadas, os vírus eluídos desse sedimento e, em seguida, concentrados por ultracentrifugação. O concentrado viral foi então purificado com Vertrel XF. Ensaios de semeadura experimental de miofago P1 nas amostras de água do reator revelaram taxa de recuperação viral de 27,7%, contra ao 16% obtidos com outros protocolos.
ABSTRACT The control of microbial growth is an increasing challenge in the production of oil and gas, since the presence of certain bacteria has economic and environmental negative impacts. Sulphate reducing bacteria are particularly problematic, since they are responsible for the biological corrosion associated with the production of hydrogen sulfide, an effect known as souring. The main form of control is the use of biocides; however, this strategy, in addition to requiring continuous application, has proven to be ineffective in the elimination of biofilms and is associated with a high risk of water contamination. Therefore, it is necessary to seek more efficient and specific approaches to microbiological control. The use of bacteriophage viruses meets these needs, because after they multiply, they usually cause cell lysis, releasing new viral particles and preventing the bacteria from proliferating. In view of this, this study proposes to establish a method for the concentration and detection of bacteriophages of Sulphate Reducing Bacteria present in reactor water from oil wells. The samples were collected from two reactors, operated in a batch fed to simulate an oil well. The reactor water samples were first clarified, viruses adsorbed to sediment were eluted and then concentrated by ultracentrifugation. The viral concentrate was then purified with Vertrel-XF. Experimental seeding of P1 myophage in water samples from the reactor revealed a viral recovery rate of 27.7%, compared to the 16% obtained by use of other protocols.
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The effect of tetracyclines used for swine food-production (tetracycline and oxytetracycline) on enriched nitrifying bacteria cultures over time was investigated in this study. Short-term exposure assays were performed in different concentrations of each antibiotic, using ammonia oxidizing bacteria (AOB) culture and nitrifying bacteria. The results pointed out a higher inhibitory effect of tetracycline on both bacterial communities. The AOB was more sensitive to antibiotic exposure when compared to the nitrifying culture. Although high antibiotic concentrations were applied, the half maximal inhibitory concentration (IC50) was achieved only for the AOB culture exposed to tetracycline at a concentration of 273 mg L-1. Nonetheless, the long-term exposure assay demonstrated a reduction of the tetracycline inhibition effect against AOB. The exposure to 100 mg L-1 of tetracycline (TC) did not show relevant influence over ammonium conversion efficiency; however, at 128 mg L-1 of TC, the efficiency decreased from 94% to 72%. Further investigation revealed that TC reduced the final effluent quality due to the development of a resistance mechanism by AOB culture against this antibiotic. This mechanism involves increasing the excretion of extracellular polymeric substances (EPS) and soluble microbial products (SMP), which probably increases BOD, and reduces ammonia consumption by the bacterial culture.
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Compostos de Amônio/análise , Nitrificação/efeitos dos fármacos , Esgotos/microbiologia , Tetraciclinas/análise , Drogas Veterinárias/análise , Águas Residuárias/microbiologia , Purificação da Água/métodos , Animais , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Oxirredução , Esgotos/química , Suínos , Tetraciclinas/toxicidade , Drogas Veterinárias/toxicidade , Águas Residuárias/químicaRESUMO
Composting is an emerging strategy for swine slurry treatment; nonetheless, significant greenhouse gases (GHG) emissions may occur during this process. We carried out two separate assays with increasing doses of dicyandiamide (DCD; up to 1.1% w/w) as a nitrification inhibitor and solutions of MgCl2 and H3PO4 (Mg/P; up to 0.09/0.06 mol kg-1) to promote struvite crystallization in order to assess their efficiencies as additives to decrease GHG emission during swine slurry cocomposting with sawdust (1:1v/v). We monitored the nitrous oxide (N2O-N), methane (CH4-C), and carbon dioxide (CO2-C) emissions and the ammonia (NH4+-N) and nitrate/nitrite (NOx-N) concentrations in compost reactors (35 L) during the first 4-5 weeks of composting. DCD had no effect on CH4-C and CO2-C emissions but decreased N2O-N losses by up to 56% compared with control. However, DCD inactivation was favored by thermophilic conditions and N2O-N emissions increased to same levels of control after 13 days. Mg/P was effective to decrease N2O-N losses only at the highest dose, which also sustained higher [NH4+-N] in the compost by the end of the assessment. Nonetheless, the use of 0.09/0.06 mol kg-1 of Mg/P also decreased CH4-C and CO2-C emissions compared with lower doses of Mg/P and unamended treatments. Overall, DCD and Mg/P amendments decreased the global warming potential (GWP) of swine slurry composting by up to 46 and 28%, respectively. The Mg/P application may be also interesting to increase the compost quality by increasing its NH4+-N availability. Graphical abstract.
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Aquecimento Global , Gases de Efeito Estufa , Animais , Dióxido de Carbono/análise , Guanidinas , Metano/análise , Óxido Nitroso/análise , Solo , SuínosRESUMO
Anticancer drugs are a class of pharmaceutical compounds that have been found in hospital, domestic, and industrial wastewaters and also in surface waters. They have been showing recalcitrance to conventional wastewater treatment technologies and present a potential risk to environment and human health, since they exhibit cytotoxic, teratogenic, and carcinogenic among other effects in higher organisms, even at low concentrations. The presence of these compounds in the environment is a recent challenge for wastewater treatment and some alternative strategies to remove them were already studied, such as white-rot fungi (WRF) technologies. Despite promising results, processes involving fungi are complex, have high reaction times, and require nutrient addition for fungus growth and maintenance. Due to this potential, strategies to make the technology feasible were studied, such as the possibility for direct application of enzymes secreted by WRF. Enzymatic processes were studied in the removal of other pharmaceuticals such as antibiotics, anti-inflammatory, and steroid hormones; however, to the best of our knowledge, there is a gap on literature about their direct action on anticancer drugs.
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Antineoplásicos/metabolismo , Lacase/metabolismo , Águas Residuárias/análise , Poluentes Químicos da Água/metabolismo , Purificação da Água/métodos , Biodegradação Ambiental , Ativação Enzimática , Eliminação de Resíduos Líquidos/métodosRESUMO
The production of biopharmaceuticals as vaccines in serum-free media results in reduced risk of contamination and simpler downstream processing. The production of enveloped viruses and viral vectors such as Semliki Forest Virus (SFV) typically requires lipids that are provided by supplementation with animal serum, so production under serum-free conditions is challenging. In this work, the capacity to deliver genetic material of SFV-viral replicon particles (SFV-VRPs) produced in BHK-21 cells adapted to serum-free medium (BHK/SFM) was evaluated. Three transgenes were evaluated: GFP used as a model protein, while hepatitis C virus nonstructural protein 3 protease domain (HCV-NS3p) and rabies virus glycoprotein (RVGP) were selected based on their distinct nature (enzyme and glycoprotein, respectively). BHK/SFM cells produced a sevenfold higher number of SFV-VRPs, as determined by qRT-PCR. These particles showed similar capacities of infecting BHK/FBS or BHK/SFM cells. GFP expression was evaluated by flow cytometry, HCV-NS3p activity by enzymatic assay, and RVGP expression by ELISA and Western Blot. Expression analysis revealed higher levels of GFP and HCV-NS3p in BHK/SFM, while the levels of RVGP were similar for BHK/SFM and BHK/FBS. In conclusion, the BHK/SFM cells showed increased SFV-VRP production yields, without affecting vector infectivity or heterologous gene expression, hence validating the use of BHK/SFM for industrial applications.
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The present study assessed the carbohydrate and sugar production from Chlorella spp. biomass harvested from a field scale reactor simulating phycoremediation of swine wastewater. The microalgae biomass was mainly composed by (%): carbohydrates (41 ± 0.4), proteins (50 ± 0.4), and lipids (1.3 ± 0.5). The residual sugar present in the biomass was extracted via acid hydrolysis. Among different concentrations of sulfuric acid tested (i.e., 47, 94, 188, 281 and 563 mM), significantly higher sugar content was obtained with 188 mM (0.496 g-sugar g-1 microalgae-DW). The concentration of sugar present in the microalgae did not differ significantly between the biomasses harvested by either centrifugation or coagulation-flocculation. Two commercially available strains of yeast (i.e., Saccharomyces cerevisiae and S. cerevisiae chardonnay) were tested for their capability to ferment sugar from lyophilized microalgae biomass. S. cerevisiae chardonnay showed a significantly faster consumption of sugar during the exponential growth phase. Both strains of yeast were capable of consuming most of the sugar added â 8 g L-1 within 24 h. Overall, the results suggest that carbohydrate-rich microalgae biomass obtained from the phycoremediation of swine wastewaters can play an important role in green design for industries seeking alternative sources of feedstock rich in sugar.
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Chlorella , Microalgas , Eliminação de Resíduos Líquidos , Animais , Biomassa , Carboidratos , Saccharomyces cerevisiae , Açúcares , Suínos , Águas ResiduáriasRESUMO
The production of biopharmaceuticals as vaccines in serum-free media results in reduced risk of contamination and simpler downstream processing. The production of enveloped viruses and viral vectors such as Semliki Forest Virus (SFV) typically requires lipids that are provided by supplementation with animal serum, so production under serum-free conditions is challenging. In this work, the capacity to deliver genetic material of SFV-viral replicon particles (SFV-VRPs) produced in BHK-21 cells adapted to serum-free medium (BHK/SFM) was evaluated. Three transgenes were evaluated: GFP used as a model protein, while hepatitis C virus nonstructural protein 3 protease domain (HCV-NS3p) and rabies virus glycoprotein (RVGP) were selected based on their distinct nature (enzyme and glycoprotein, respectively). BHK/SFM cells produced a sevenfold higher number of SFV-VRPs, as determined by qRT-PCR. These particles showed similar capacities of infecting BHK/FBS or BHK/SFM cells. GFP expression was evaluated by flow cytometry, HCV-NS3p activity by enzymatic assay, and RVGP expression by ELISA and Western Blot. Expression analysis revealed higher levels of GFP and HCV-NS3p in BHK/SFM, while the levels of RVGP were similar for BHK/SFM and BHK/FBS. In conclusion, the BHK/SFM cells showed increased SFV-VRP production yields, without affecting vector infectivity or heterologous gene expression, hence validating the use of BHK/SFM for industrial applications.
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Viral hepatitis caused by the hepatitis C virus (HCV) affects millions of people worldwide. The non-structural protein 3 (NS3), one of the most conserved proteins in HCV, is the target of many therapeutic studies. The NS3 protease domain (NS3p) has a range of cytotoxic T lymphocyte (CTL) epitopes, and synthesizing the protein inside the cells is the most appropriate way to present it to the immune system. We developed a tool to study this kind of presentation, using two vectored particle (VP) systems, one based on the Semliki Forest virus (SFV) and the other on HCV pseudoparticles (HCVpp), both carrying the protease domain of the NS3 gene. In addition to producing the particles, we developed a method to quantify these VPs using qRT-PCR. We produced batches of approximately 2.4x10(4) SFV-NS3p/mu L and 4.0x10(2) HCVpp-NS3p/mu L. BHK-21 and HuH-7 cells treated with the VPs expressed the NS3 protein, thus showing the functionality of this system.
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The effects of nitrogen (N) and/or phosphorus (P) starvation on the biochemical composition of native microalgae Chlorella spp. polyculture obtained from the phycoremediation of swine wastewaters were investigated. Microalgae-specific growth rate of 1.2 day(-1) was achieved (30.3 mg L(-1) day(-1)). PO4 (-2) and NH3 were completely removed from swine digestate effluent after 3 and 11 days, respectively. Microalgae harvested immediately after nutrient removal showed high protein (56-59 %) and carbohydrate (25-34 %) but low lipid (1.8-3 %) contents. Depletion of N or P alone stimulated carbohydrate production at the expenses of proteins. Significant lipid accumulation from 3 % ± 0.5 to 16.3 % ± 0.8 was reached only after 25 days following N and P starvation as demonstrated by Nile red-stained cells. Regarding to the effects of harvesting methods on cellular biochemical composition, circumstantial evidences indicate that coagulation-flocculation with tannin may lead to lower protein and lipid amounts but increased carbohydrate content (p < 0.01) as compared to centrifugation.
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Biodegradação Ambiental , Carboidratos/biossíntese , Nitrogênio/metabolismo , Fósforo/metabolismo , Animais , Carboidratos/química , Chlorella/metabolismo , Lipídeos/biossíntese , Lipídeos/química , Microalgas/metabolismo , Suínos , Taninos/química , Taninos/metabolismo , Águas Residuárias/químicaRESUMO
This work investigated the effects of swine wastewater-derived biogas on microalgae biomass production and nutrient removal rates from piggery wastewater concomitantly with biogas filtration. Photobioreactors with dominant Scenedesmus spp. were prepared using non-sterile digestate and exposed to different photoperiods. In the presence of biogas and autotrophic conditions microalgae yield of 1.1±0.2 g L(-1) (growth rate of 141.8±3.5 mg L(-1) d(-1)) was obtained leading to faster N-NH3 and P-PO4(3-) assimilation rate of 21.2±1.2 and 3.5±2.5 mg L(-1) d(-1), respectively. H2S up to 3000 ppmv was not inhibitory and completely removed. Maximum CO2 assimilation of 219±4.8 mg L(-1) d(-1) was achieved. Biological consumption of CH4 up to 18% v/v was verified. O2 up to 22% v/v was controlled by adding acetate to exacerbate oxygen demand by microorganisms. Microalgae-based wastewater treatment coupled to biogas purification accelerates nutrient removal concomitantly producing valuable biomass and biomethane.
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Biocombustíveis/análise , Microalgas/metabolismo , Nitrogênio/isolamento & purificação , Fósforo/isolamento & purificação , Scenedesmus/metabolismo , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Amônia/isolamento & purificação , Animais , Biodegradação Ambiental , Análise da Demanda Biológica de Oxigênio , Biomassa , Dióxido de Carbono/análise , Filtração , Sulfeto de Hidrogênio/análise , Metano/análise , Microalgas/crescimento & desenvolvimento , Fotobiorreatores/microbiologia , Fotoperíodo , Scenedesmus/crescimento & desenvolvimento , SuínosRESUMO
Nitrifying bacteria are highly susceptible to silver nanoparticles (AgNPs). However, the effect of sublethal exposure to AgNPs after their release of nitrogenous compounds of environmental concern (e.g., the greenhouse gas nitrous oxide [N2 O] and the common water pollutant nitrite [NO2 -]) has not been systematically investigated. The present study reports the effect of AgNPs (and potentially released silver ions [Ag(+) ]) on NO2 - and N2 O production by Nitrosomonas europaea, and on the transcription of the associated genes. The release of NO2 - was more negatively affected than the production of N2 O. For example, exposure to AgNPs at 0.075 mg/L temporarily enhanced N2 O production (by 12%) without affecting nitrite release, whereas higher AgNP concentrations (>0.25 mg/L) inhibited NO2 - release (by >12%) but not N2 O production. Transcriptomic analyses corroborated these trends; AgNPs at 0.075 mg/L increased the expression of the nitric oxide reductase gene (norQ) associated with N2 O production (by 5.3-fold to 12.8-fold), whereas both 0.075 mg/L of Ag(+) and 0.75 mg/L of AgNPs down-regulated the ammonia monooxygenase gene (amoA2; by 0.08-fold to 0.15-fold and 0.32-fold to 0.64-fold, respectively), the nitrite reductase gene (nirK; by 0.01-fold to 0.02-fold and 0.22-fold to 0.44-fold, respectively), and norQ (by 0.11-fold to 0.15-fold and 0.32-fold to 0.57-fold, respectively). These results suggest that AgNP release to sewage treatment plants and land application of AgNP-containing biosolids should be minimized because of their potential temporary stimulation of N2 O release and interference with nitrification. Environ Toxicol Chem 2015;34:2231-2235. © 2015 SETAC.
Assuntos
Nanopartículas Metálicas/química , Nitrosomonas europaea/metabolismo , Óxido Nitroso/metabolismo , Prata/química , Cromatografia Gasosa , Nanopartículas Metálicas/toxicidade , Nitrificação/efeitos dos fármacos , Nitritos/análise , Nitritos/metabolismo , Nitrosomonas europaea/efeitos dos fármacos , Nitrosomonas europaea/enzimologia , Óxido Nitroso/análise , Oxirredutases/genética , Oxirredutases/metabolismo , Transcrição GênicaRESUMO
Groundwater contamination is becoming a serious problem in many Brazilian regions. European countries started to deal with this issue in the 1980s, mainly caused by the extensive usage of nitrogenous fertilizers and the absence of domestic wastewater treatment. Due to its high solubility, nitrate readily passes through the soil and reaches the aquifer. Thereafter, this ion moves, following groundwater flow, and can be found several kilometers from the area where the pollution occurred. Concern about nitrate contamination is due to the link found between this contaminant and various human health diseases, such as methemoglobin and cancer. Studies carried out in France enabled the design and implementation of several biological denitrification plants throughout the country, in order to remove nitrate from its contaminated groundwater. Heterotrophic denitrification facilities shown to be adequate to treat high water flows with satisfactory nitrate removal efficiency, especially when static media supports are employed. The objective of this research was to evaluate the existence of denitrifying microorganisms in bamboo (Bambusa tuldóides) and verify the feasibility of their use to inoculate a pilot-scale fixed-bed bioreactor. The support material selected to fill the bioreactor bed was commercial polypropylene Pall rings, since such support has a high porosity associated with a wide superficial area. The bioreactor was able to produce and retain a large amount of cells. Using ethanol as carbon source, nitrate (N-NO3(-)) removal efficiency of the bioreactor stood around 80 % for a maximum nitrogen loading rate of approximately 6.5 mg N-NO3 (-) L(-1) h(-1).
Assuntos
Bambusa/química , Desnitrificação , Água Potável , Purificação da Água , Sequência de Bases , Reatores Biológicos , Primers do DNA , Reação em Cadeia da Polimerase em Tempo RealRESUMO
The present work focuse on the impact of O2, CO2 and ethylene concentrations on ripening rate control of bananas as a contribution for the development of domestic equipments that could allow the user to drive the fruit shelf live. It represented the adjustment of metabolic activity rates in order to manage the maturity process. Ripening variables such as ethylene and CO2 concentrations and temperature were adjusted to accelerate or slow down the process, while the maturity degree was monitored through the physical and chemical parameters and sensorial analysis. Therefore, the objective of this work was to evaluate the influence of these parameters to manage the banana ripening. The optimum temperature was at 25 ºC of storage. The presence of oxygen, CO2 withdraws and ethylene injection were relevant for the ripening process. The "ready-to-eat" quality was achieved in 6 days in confined system. The use of ethylene as trigger was adequate to accelerate the ripening process with advantages in fruit color.
O presente trabalho foca no impacto da concentração de O2, CO2 e etileno no controle da taxa de amadurecimento de bananas, como contribuição para o desenvolvimento de equipamentos domésticos que permitam o controle pelo próprio usuário da vida de prateleira de frutas. Isto representa o ajuste das atividades metabólicas para garantir o controle do amadurecimento. Variáveis como concentração de etileno e CO2 e temperatura foram ajustadas para acelerar ou reduzir o processo, enquanto que o grau de maturação foi monitorado através de parâmetros físico-químicos e sensoriais. Desta forma, o objetivo deste trabalho foi avaliar a influência destes parâmetros para controlar o amadurecimento de banana. A temperatura ótima de amadurecimento foi 25ºC. A presença de O2, a retirada de CO2 e a injeção de etileno foram relevantes no processo. A qualidade "pronto-para-consumo" foi obtida em 6 dias em sistema confinado. O uso de etileno como gatilho é adequado para acelerar o amadurecimento, com vantagens para a cor do produto.