RESUMO
Eligibility and indication for autologous hematopoietic stem cell transplantation (HSCT) in patients with lymphoma are increasing. Acute kidney injury (AKI) is a known complication of HSCT with studies including a miscellaneous of hematological diagnoses and using different definitions of AKI. We aimed to evaluate incidence, risk factors and prognostic impact of AKI post-HSCT in patients with lymphoma submitted to autologous HSCT using the KDIGO classification with both serum creatinine and urinary output criteria. We performed a single-center retrospective cohort study including patients with lymphoma admitted for autologous HSCT. We used survival analysis with competing risks to evaluate cumulative incidence of AKI, AKI risk factors and AKI impact on disease-free survival. We used Cox regression for impact of AKI on overall survival. We used backward stepwise regression to create multivariable models. A total of 115 patients were included. Cumulative incidence of AKI: 63.7% 100 d post-HSCT. First diagnosis criteria: creatinine in 54.8%, urinary output in 41.1% and both in 4.1%. AKI highest stage: 1 in 57.5%, 2 in 17.8% and 3 in 24.7%. Variables independently associated with higher incidence of AKI were: use of nephrotoxic drugs (HR: 2.87, 95% CI: 1.07-7.65; p = 0.035), mucositis (HR: 1.95, 95% CI: 1.16-3.29; p = 0.012) and shock (HR: 2.63, 95% CI: 1.19-5.85; p = 0.017). Moderate to severe AKI was independently associated with lower overall survival (HR: 2.04, 95% CI: 1.06-3.94; p = 0.033). No association with relapse nor progression to chronic kidney disease (CKD) was found. AKI affects almost two thirds of patients with lymphomas submitted to autologous HSCT. Nephrotoxic drugs, mucositis and shock are important independent AKI risk factors. More than one third of AKI episodes are moderate to severe and these are associated with lower overall survival.
Assuntos
Injúria Renal Aguda , Transplante de Células-Tronco Hematopoéticas , Linfoma , Mucosite , Humanos , Creatinina , Estudos Retrospectivos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Linfoma/complicações , Linfoma/terapiaRESUMO
OBJECTIVE: Cephalic arch stenosis (CAS) is an important and recurring problem arising in hemodialysis patients because of the requirement for repeated interventions to maintain patency. The aim of this study was to determine predictive factors for recurrence of CAS after successful angioplasty. METHODS: A retrospective, case-control study was conducted at two ambulatory vascular access (VA) centers. All patients with a dysfunctional VA referred for an angiographic procedure and with a documented CAS as evidenced during the endovascular intervention (EI) between January 1, 2013, and December 31, 2015, were enrolled; 15 patients in whom an efficacious intervention was not possible were excluded. The study thus concerned 375 EIs using percutaneous transluminal angioplasty without stent placement on 241 VAs for CAS (9% of all procedures performed) during a 3-year period. Patients were compared regarding the absence (group 1; n = 181) or presence (group 2; n = 60) of recurrent CAS. We defined recurrence as that which occurred within 180 days of the previous successful EI for CAS. Any CAS diagnosed and treated >180 days after a previous one was considered a novel CAS and not a recurrence. Multivariate analysis was performed to determine variables independently associated with recurrence of CAS. Kaplan-Meier analysis was performed for determination of primary and assisted primary patency in this population. RESULTS: The recurrence rate of CAS was high (25%). Patients in both groups had similar demographic characteristics, time on hemodialysis, and mean dialysis dose and access flow rate at referral (P > .05). Multivariate analysis provided a significant discriminatory influence pertaining to diabetes (hazard ratio [HR], 2.054; 95% confidence interval [CI], 1.22-3.46; P = .007), residual stenosis even though it was <30% (HR, 1.86; 95% CI, 1.005-3.439; P = .048), and the finding of an isolated CAS lesion (HR, 0.445; 95% CI, 0.219-0.905; P = .025) in comparing group 1 and group 2. All other variables lost statistical significance on multivariate analysis. Primary patency at 6 months was 72%, increasing to an assisted primary patency of 89% at 6 months. The median durations of primary patency and assisted primary patency were 9.5 months and 15.6 months, respectively. CONCLUSIONS: Multivariate analysis showed that diabetes and residual stenosis (albeit <30%) were predictive of recurrence, whereas the finding of an isolated CAS lesion as opposed to stenoses in multiple locations was shown to be negatively associated with recurrent CAS, appearing to be "protective".
Assuntos
Angioplastia , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Complicações do Diabetes/cirurgia , Oclusão de Enxerto Vascular/cirurgia , Diálise Renal , Extremidade Superior/irrigação sanguínea , Idoso , Angiografia , Estudos de Casos e Controles , Constrição Patológica , Complicações do Diabetes/diagnóstico por imagem , Feminino , Oclusão de Enxerto Vascular/diagnóstico por imagem , Hospitais de Veteranos , Humanos , Masculino , Recidiva , Sistema de Registros , Reoperação , Estudos Retrospectivos , Grau de Desobstrução VascularRESUMO
In this work, a turn-off photoluminescent sensing proof-of-concept based on blue luminescent graphene quantum dots (GQDs) as the fluorescent probe was developed. For that purpose, GQDs optical response was related with the catalytic enzymatic activity of alkaline phosphatase (ALP), in the presence of hydroquinone diphosphate (HQDP). The hydrolysis of HQDP by ALP generated hydroquinone (HQ). The oxidation of HQ, enzymatically produced, to p-benzoquinone (BQ) resulted in the quenching of GQDs fluorescence (FL). Therefore, the developed luminescent sensing mechanism allowed the FL quenching with ALP activity to be related and thus quantified the concentration of ALP down to 0.5 nM of enzyme. This innovative design principle appears as a promising tool for the development of enzymatic sensors based on ALP labeling with fluorescent detection or even for direct ALP luminescent quantification in an easy, fast and sensitive manner.
Assuntos
Fosfatase Alcalina/análise , Hidroquinonas/química , Medições Luminescentes/métodos , Organofosfatos/química , Pontos Quânticos/química , Fosfatase Alcalina/química , Fosfatase Alcalina/metabolismo , Fluorescência , Corantes Fluorescentes/química , Grafite , Hidrólise , Limite de Detecção , Reprodutibilidade dos TestesRESUMO
Although the prognostic effect of obesity has been studied in critically ill patients its impact on outcomes of septic patients and its role as a risk factor for acute kidney injury (AKI) is not consensual. We aimed to analyze the impact of obesity on the occurrence of AKI and on in-hospital mortality in a cohort of critically ill septic patients. This study is retrospective including 456 adult patients with sepsis admitted to the Division of Intensive Medicine of the Centro Hospitalar Lisboa Norte (Lisbon, Portugal) between January 2008 and December 2014. Obesity was defined as a body mass index of 30 kg/m2 or higher. The Kidney Disease Improving Global Outcomes classification was used to diagnose and classify patients developing AKI. AKI occurred in 87.5% of patients (19.5% with stage 1, 22.6% with stage 2 and 45.4% with stage 3). Obese patients developed AKI more frequently than non-obese patients (92.8% versus 85.5%, p = .035; unadjusted OR 2.2 (95% CI: 1.04-4.6), p = .039; adjusted OR 2.31 (95% CI: 1.07-5.02), p = .034). The percentage of obese patients, however, did not differ between AKI stages (stage 1, 25.1%; stage 2, 28.6%; stage 3, 15.4%; p = .145). There was no association between obesity and mortality (p = .739). Of note, when comparing AKI patients with or without obesity in terms of in-hospital mortality there were also no significant differences between those groups (38.4% versus 38.4%, p = .998). Obesity was associated with the occurrence of AKI in critically ill patients with sepsis; however, it was not associated with in-hospital mortality.
Assuntos
Injúria Renal Aguda/epidemiologia , Estado Terminal/mortalidade , Mortalidade Hospitalar , Obesidade/complicações , Sepse/mortalidade , Injúria Renal Aguda/etiologia , Idoso , Feminino , Humanos , Unidades de Terapia Intensiva/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Portugal/epidemiologia , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Sepse/complicaçõesRESUMO
Herein, a new miniaturized analytical instrumentation for electrochemiluminescence (ECL) assays is presented. A photodiode integrated in an ECL cell combined with a potentiostat/galvanostat, all integrated in a one-piece instrument (µSTAT ECL), was developed. In addition, a complementary micro-spectrometer integrated in a similar ECL cell for luminescence spectra recording is also proposed. Both cells are intended to be used with screen-printed electrodes and all the devices are portable and small sized. Their performance was corroborated with two innovative proofs-of-concept that centered on the luminol transduction chemistry: a first time reported ECL assay based on the enzymatic reaction between an indoxyl substrate and the enzyme alkaline phosphatase, and the electrochemiluminescence resonance energy transfer (ECL-RET) process triggered by the electro-oxidized luminol to the acceptor fluorescein. The photodiode system revealed to be more sensitive than the spectrometer device in collecting the light; however, with the latter, it is possible to discriminate different luminescent species according to their maximum wavelength emission, which is extremely useful for carrying out simple and simultaneous ECL multiplex analyzes. The spectrometer device works as an excellent accessory to couple with the µSTAT ECL instrument, complementing the experiments. Graphical abstract Schematic representation of the ECL-RET: from luminol-H2O2 system to fluorescein, the micro-spectrometer for the light collection and the 3D representation of the ECL-RET reaction.
RESUMO
Physical examination (PE), and surveillance and monitoring techniques should be a core part of standard care provided to hemodialysis patients. This study aimed to define which referral criteria within a vascular access (VA) program were associated with indication for therapeutic endovascular intervention (EI). Retrospective study at two vascular centers, considering 1265 procedures between 1 November 2012 and 30 November 2013. All 617 arteriovenous fistulas (AVFs) and 648 arteriovenous grafts (AVGs) referred for angiography were enrolled. Each population was divided into two groups regarding absence (group 1) or presence (group 2) of a significant lesion on the angiogram, contemplating formal indication for EI. On multivariate analysis, factors independently associated with presence of a significant lesion in AVFs were referral due to increased dynamic venous pressure (p = 0.01), suspected stenosis by abnormal PE (p = 0.019), confirmed reduction in access flow rate (p = 0.003), and mean Kt/V < 1.4 (p = 0.004). In AVGs, although multivariate analysis did not find independent association of studied factors with presence of significant stenoses, 97.2% of the exams revealed relevant lesions previously suspected clinically. Aside from surveillance strategies, monitoring strategies including routine PE of the VA are imperative as an integral part of evaluation, especially in AVFs.
Assuntos
Angiografia , Fístula Arteriovenosa/diagnóstico por imagem , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Oclusão de Enxerto Vascular/diagnóstico por imagem , Seleção de Pacientes , Encaminhamento e Consulta , Adulto , Idoso , Idoso de 80 Anos ou mais , Angioplastia , Fístula Arteriovenosa/complicações , Feminino , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/terapia , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/diagnóstico por imagem , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Exame Físico , Diálise Renal , Estudos Retrospectivos , Dispositivos de Acesso Vascular/efeitos adversosRESUMO
Increasing use of tracheal expandable metallic hybrid stents will lead to common encounters with these devices in emergency airway management. The presence of these stents qualifies any patient as a challenge when an emergency tracheostomy is needed. We report an unorthodox technique of tracheostomy with concomitant removal of tracheal stent, without any major complications. Although the combined approach with bronchoscopy and tracheostomy has been reported in similar cases, we present a safe procedure when rigid bronchoscopy is not available.
Assuntos
Broncoscopia , Remoção de Dispositivo , Traqueostomia , Humanos , Traqueostomia/efeitos adversos , Traqueostomia/instrumentação , Traqueostomia/métodos , Remoção de Dispositivo/métodos , Broncoscopia/métodos , Stents/efeitos adversos , Traqueia/cirurgia , Masculino , Estenose Traqueal/cirurgia , Estenose Traqueal/terapia , Estenose Traqueal/etiologia , FemininoRESUMO
PURPOSE: Organ shortage greatly limits treatment of patients with end-stage chronic kidney. Maastricht type 2 donation after circulatory death (DCD) has been shown to have similar results in long term outcomes in kidney transplantation, when compared with brain dead donation. Our main goal was to assess Maastricht type 2 DCD and evaluate factors that impact on early graft function. METHODS: A retrospective study was conducted in an ECMO Referral Centre. All patients who received a kidney transplant from Maastricht type 2 DCD were included in study. Early graft function and short term outcomes were assessed. RESULTS: From October 2017 to December 2022, 47 renal grafts were collected from 24 uDCD donors. Median warm ischemia time was 106 min (94-115), cannulation time was 10 min (8; 20) and duration of extracorporeal reperfusion (ANOR) was 180 min (126-214). Regarding early graft function, 25% had immediate graft function, 63.6% had delayed graft function and 11.4% had primary non-function (PNF). There was a correlation between cannulation time (p = 0.006) and ANOR with PNF (p = 0.016). CONCLUSIONS: Cannulation time and ANOR were the main factors that correlated with PNF. Better understanding of underlying mechanisms should be sought in future studies to reduce the incidence of PNF.
Assuntos
Transplante de Rim , Obtenção de Tecidos e Órgãos , Humanos , Masculino , Estudos Retrospectivos , Feminino , Pessoa de Meia-Idade , Adulto , Função Retardada do Enxerto , Doadores de Tecidos/provisão & distribuição , Falência Renal Crônica/cirurgia , Falência Renal Crônica/terapia , Isquemia QuenteRESUMO
Crithmum maritimum L. (sea fennel), an edible xerophyte of coastal habitats, is considered an emerging cash crop for biosaline agriculture due to its salt-tolerance ability and potential applications in the agri-food sector. Here, the nutritional value and bioactive properties of sea fennel are described. Sea fennel leaves, flowers, and schizocarps are composed of carbohydrates (>65%) followed by ash, proteins, and lipids. Sea fennel's salty, succulent leaves are a source of omega-6 and omega-3 polyunsaturated fatty acids, especially linoleic acid. Extracts obtained from flowers and fruits/schizocarps are rich in antioxidants and polyphenols and show antimicrobial activity against Staphylococcus aureus, Staphylococcus epidermis, Candida albicans, and Candida parapsilosis. Plant material is particularly rich in sodium (Na) but also in other nutritionally relevant minerals, such as calcium (Ca), chlorine (Cl), potassium (K), phosphorus (P), and sulfur (S), beyond presenting a potential prebiotic effect on Lactobacillus bulgaricus and being nontoxic to human intestinal epithelial Caco-2 model cells, up to 1.0% (w/v). Hence, the rational use of sea fennel can bring nutrients, aroma, and flavor to culinary dishes while balancing microbiomes and contributing to expanding the shelf life of food products.
RESUMO
The first electrochemical immunosensor (EI) for the detection of antibodies against deamidated gliadin peptides (DGP) is described here. A disposable nanohybrid screen-printed carbon electrode modified with DGP was employed as the transducer's sensing surface. Real serum samples were successfully assayed and the results were corroborated with an ELISA kit. The presented EI is a promising analytical tool for celiac disease diagnosis.
Assuntos
Técnicas Biossensoriais/métodos , Doença Celíaca/diagnóstico , Gliadina/imunologia , Anticorpos/sangue , Doença Celíaca/imunologia , Gliadina/metabolismo , Humanos , Imunoensaio/métodos , Imunoglobulina G/análise , Nanotubos de Carbono , Fragmentos de Peptídeos/imunologia , Transglutaminases/metabolismoRESUMO
Glycoforms (and other post-translational modifications) of otherwise identical proteins can indicate pathogenesis/disease state and hence new tools to detect and sense a protein's glycosylation status are essential. Antibody-based assays against specific protein sequences do not typically discriminate between glycoforms. Here we demonstrate a 'sandwich' bio-assay approach, whereby antibodies immobilised onto biolayer interferometry sensors first select proteins, and then the specific glycoform is identified using gold nanoparticles functionalised with lectins which provide signal enhancement. The nanoparticles significantly enhance the signal relative to lectins alone, allowing glycoform specific detection as low as 0.04 µg mL-1 (1.4 nM) in buffer, and crucially there is no need for an enrichment step and all steps can be automated. Proof of concept is demonstrated using prostate specific antigen: a biomarker for prostate cancer, where glycoform analysis could distinguish between cancerous and non-cancerous status, rather than only detecting overall protein concentration.
Assuntos
Lectinas , Nanopartículas Metálicas , Humanos , Masculino , Anticorpos , Glicosilação , Ouro , Lectinas/metabolismo , Neoplasias da Próstata/diagnóstico , Antígeno Prostático Específico/análiseRESUMO
Seaweeds are a sustainable source of protein and lipids that may be used to replace fish by-products in aquaculture feed. This study aimed at using the macroalgae Pelvetia canaliculata as an ingredient in gilthead seabream (Sparus aurata) feed, either as freeze-dried powder or as algae residue (waste) that was obtained after the supplementation of sunflower oil. The formulated diets and the fish muscle were analyzed concerning the proximate composition and the fatty acid profile. The health lipid indices hypocholesterolemic/hypercholesterolemic (h/H), atherogenic (AI), thrombogenic (TI), as well as n-3/n-6 and polyunsaturated fatty acid/saturated fatty acid (PUFA/SFA) ratios were calculated. Additionally, the peroxidizability index (PI) was determined. No differences were observed in the proximate composition of fish muscle regardless of the diet used. Fish fed a diet supplemented with 10% of algae waste (W10) stand out for the highest content in oleic acid (C18:1 n-9), and the lowest in both linoleic (C18:2 n-6) and palmitic (C16:0) fatty acids. All fish samples showed values of health lipid indices within the limits recommend for a nutritional balanced diet. These results highlight that fish fed diets supplemented with P. canaliculata are sources of healthy lipids that might be consumed on a regular basis to prevent cardiovascular diseases.
RESUMO
Thirty-one 2'-hydroxychalcones were prepared via solid-phase synthesis by base-catalyzed aldol condensation of substituted 2'-hydroxyacetophenones and benzaldehydes. Chalcones were tested for their growth inhibitory activity in three human tumor cell lines (MCF-7, NCI-H460 and A375-C5) using the SRB assay. Results revealed that several of the tested compounds caused a pronounced dose-dependent growth inhibitory effect on the tumor cell lines studied in the low micromolar range. To gain further insight on the cellular mechanism of action of this class of compounds, studies of their effect on cell cycle profile as well as on induction of cellular apoptosis were also carried out. Generally, the tested chalcones interfered with the cell cycle profile and increased the percentage of apoptotic MCF-7 cells. The results here presented may help to identify new chalcone-like structures with optimized cell growth inhibitory activity which may be further tested as potential antitumor agents.
Assuntos
Antineoplásicos/síntese química , Chalconas/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose , Benzaldeídos/química , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Chalconas/síntese química , Chalconas/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Técnicas de Síntese em Fase Sólida , Relação Estrutura-AtividadeRESUMO
Six prenyl (=3-methylbut-2-en-1-yl) chalcones (=1,3-diphenylprop-2-en-1-ones), 2-7, and one natural non-prenylated chalcone, 1, have been synthesized and evaluated for their in vitro growth-inhibitory activity against three human tumor cell lines. A pronounced dose-dependent growth-inhibitory effect was observed for all prenylated derivatives, except for 7. The chalcone possessing one prenyloxy group at C(2'), i.e., 2, was the most active derivative against the three human tumor cell lines (5.9Assuntos
Apoptose/efeitos dos fármacos
, Pontos de Checagem do Ciclo Celular/efeitos dos fármacos
, Chalcona/análogos & derivados
, Linhagem Celular Tumoral
, Chalcona/síntese química
, Chalcona/toxicidade
, Ensaios de Seleção de Medicamentos Antitumorais
, Humanos
, Estereoisomerismo
RESUMO
Crithmum maritimum L., or sea fennel, is an edible halophyte plant, rich in phenolic compounds with antioxidant and antimicrobial activities, that naturally grows in Mediterranean coasts. This study aims to incorporate bioactive compounds extracted from lyophilized Crithmum maritimum to sunflower oil assisted by ultrasounds (UAE), to improve its biological value and oxidative stability. UAE conditions were optimized as a function of time (5-20 min) and lyophilized plant concentration (5-20% m/v). The experiments were dictated by a central composite rotatable matrix. Oxidation products were not influenced by UAE conditions. Acidity, chlorophyll, and carotenoid contents were affected by both factors, while total phenols, flavonoids, and antioxidant activity (FRAP method) only increased with plant concentration. Response surfaces were fitted to these experimental results. Flavonoids were highly related with oil antioxidant activity. No sensory defects were detected in supplemented oil (12.5% m/v plant/5 min UAE). The oxidative stability of this oil was evaluated at 60 °C/12 days. Chlorophylls, phenols, radical scavenging (DPPH), and antioxidant activities decreased over time but were always higher than the values in non-supplemented oil (8.6 and 7-fold with FRAP and DPPH, respectively). C. maritimum presented high amounts of bioactive compounds with antioxidant activity, adequate for sunflower oil supplementation by UAE.
RESUMO
Anthropogenic CO2 emissions have led to the warming and acidification of the oceans. Although, there is a growing of evidence showing that simultaneous occurrence of ocean acidification and ocean warming are threats to marine organisms, information on their combined effect on coastal shrimp species remains scarce. The purpose of this study was to estimate the combined effects of seawater acidification and warming on growth-related traits and biochemical responses of P. elegans juveniles. In this work, shrimp were exposed for 65 days at 4 experimental conditions: pH 8.10 * 18 °C, pH 7.80 * 18 °C, pH 8.10 * 22 °C, pH 7.80 * 22 °C. The results showed that low pH decreases the lipid content by â¼13% (p < 0.05). Higher temperature reduced the condition factor by â¼11%, the protein content by â¼20%, the PUFA by â¼8,6% and shortened moulting events by 5 days (p > 0.05) while the SFA increased â¼9.4%. The decrease in condition factor and protein was however more prominent in organisms exposed to the combination of pH and temperature with a decrease of â¼13% and â¼21%, respectively. Furthermore, essential fatty acids as EPA and DHA also decreased by â¼20% and â¼6.6% in low pH and higher temperature condition. Despite this study suggest that warming may have a greater impact than acidification, it has been shown that their combined effect can exacerbate these impacts with consequences for the shrimp's body size and biochemical profile.
Assuntos
Palaemonidae , Água do Mar , Animais , Aquecimento Global , Concentração de Íons de Hidrogênio , Oceanos e Mares , Água do Mar/química , TemperaturaRESUMO
Helichrysum italicum (H. italicum) is a halophyte shrub with bright yellow flowers with a strong curry-like aroma. The essential oils of H. italicum have been used in the production of cosmetics and pharmaceuticals, due to their antiallergic and anti-inflammatory properties. In the agri-food sector, H. italicum flowers can be used for seasoning and flavoring food, and as natural food preservatives. Here, we report on the composition, bioactive compounds, and nutritive value of H. italicum flowers. Flowers were mainly composed of carbohydrates (>80 % dry weight), followed by minerals (6.31 ± 0.95 % dw), protein (5.44 ± 0.35 % dw), and lipids (3.59 % ± 0.53 % dw). High percentages of Fe, Zn, Ca, and K were found in the flower material, along with a high content in antioxidants, polyphenols, and carotenoids, as corroborated by the nuclear magnetic resonance (NMR) data. Flowers were mainly composed of saturated fatty acids (SFAs) (54.50 ± 0.95 % of total FA), followed by polyunsaturated fatty acids (PUFAs) (37.73 ± 1.25 % of total FA) and monounsaturated fatty acids (MUFAs) (7.77 ± 0.34 %), as detected by gas chromatography mass spectrometry (GC-MS). The omega-6 PUFA linoleic acid (22.55 ± 0.76 % of total FA) was the most abundant fatty acid found. Flower extracts showed antimicrobial activity against Saccharomyces cerevisiae and Komagataella phaffii, as well as against Gram-negative (Klebsiella pneumoniae) and Gram-positive (Staphylococcus aureus) bacteria. H. italicum flower material was nontoxic to human intestinal Caco-2 model cells at concentrations up to 1.0 % w/v.
Assuntos
Helichrysum , Óleos Voláteis , Células CACO-2 , Flores/química , Helichrysum/química , Humanos , Valor Nutritivo , Óleos Voláteis/químicaRESUMO
Seaweeds exhibit high nutritional value due to a balanced concentration of proteins, vitamins and minerals, a high concentration of low digestibility polysaccharides, and reduced levels of lipids, many of which are n-3 and n-6 fatty acids. The species Agarophyton vermiculophyllum is no exception and, as such, a comprehensive study of the chemical and nutritional profile of this red seaweed was carried out for 1 year. Seasonal variations in moisture, ash, protein and amino acids content, crude fibers, ascorbic acid, agar, lipids, and the corresponding fatty acid profile, were analyzed. We found low levels of fatty acids and a high protein content, but also noticed interesting seasonal change patterns in these compounds. The present study gives insights on the environmental conditions that can lead to changes in the nutritional composition of this species, aiming, therefore, to bring new conclusions about the manipulation of environmental conditions that allow for maximizing the nutritional value of this seaweed.
RESUMO
Efficiently detecting peanut traces in food products can prevent severe allergic reactions and serious health implications. This work presents the development of an electrochemical dual immunosensor for the simultaneous analysis of two major peanut allergens, Ara h 1 and Ara h 6, in food matrices. A sandwich immunoassay was performed on a dual working screen-printed carbon electrode using monoclonal antibodies. The antibody-antigen interaction was detected by linear sweep voltammetry through the oxidation of enzymatically deposited silver, which was formed by using detection antibodies labeled with alkaline phosphatase and a 3-indoxyl phosphate/silver nitrate mixture as the enzymatic substrate. The assay time was 2 h 20 min, with a hands-on time of 30 min, and precise results and low limits of detection were obtained (Ara h 1: 5.2 ng·mL-1; Ara h 6: 0.017 ng·mL-1). The selectivity of the method was confirmed through the analysis of other food allergens and ingredients (e.g., hazelnut, soybean and lupin). The dual sensor was successfully applied to the analysis of several food products and was able to quantify the presence of peanuts down to 0.05% (w/w). The accuracy of the results was confirmed through recovery studies and by comparison with an enzyme-linked immunosorbent assay. Tracking food allergens is of utmost importance and can be performed using the present biosensor in a suitable and practical way.
RESUMO
In this study, Pelvetia canaliculata L. macroalga, collected from the Atlantic Portuguese coast, was used as a source of bioactive compounds, mostly antioxidants, to incorporate them in sunflower oil with the aim of increasing its biological value and oxidative stability. The lyophilized alga was added to the oil, and ultrasound-assisted extraction (UAE) was performed. Algae concentration and UAE time varied following a central composite rotatable design (CCRD) to optimize extraction conditions. The following parameters were analyzed in the oils: oxidation products, acidity, color, chlorophyll pigments, carotenoids, flavonoids, total phenolic content, antioxidant activity by DPPH (2,2-diphenyl-1-picrylhydrazyl) and FRAP (ferric reducing antioxidant power) assays, and sensory analysis. Extraction conditions did not affect the acidity and the amount of oxidation products in the oil. Chlorophylls and carotenoid contents increased with algae concentration, while flavonoid extraction did not depend on algae content or UAE time. Total phenolics in the oil were highly related only to FRAP antioxidant activity. Storage experiments of supplemented oil (12.5% algae; 20 min UAE) were carried out under accelerated oxidation conditions at 60 °C/12 days. Antioxidant activity (FRAP) of supplemented oil was 6-fold higher than the value of non-supplemented oil. Final samples retained 40% of their initial antioxidant activity. The presence of algae extracts contributed to the increased oxidative stability of sunflower oil.