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1.
Blood Adv ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38810260

RESUMO

Studies comparing the efficacy of post-transplant cyclophosphamide (PTCy) to conventional calcineurin inhibitor (CNI)-based GVHD prophylaxis regimens in Hodgkin lymphoma (HL) patients are scarce. This study aimed to compare the outcomes of HL patients undergoing hematopoietic stem cell transplantation from HLA-matched donors who received GVHD prophylaxis with either PTCy or conventional CNI-based regimens, using data reported to the EBMT database between January 2015 and December 2022. Among the cohort, 270 recipients received conventional CNI-based prophylaxis and 176 received PTCy prophylaxis. Notably, PTCy prophylaxis was associated with delayed hematopoietic recovery, but also with a lower risk of chronic (25% versus 43%, p<0.001) and extensive chronic GVHD (13% versus 28% p=0.003) compared to the CNI-based cohort. The 2-year cumulative incidence of non-relapse mortality and relapse were 11% versus 17% (p=0.12), and 17% versus 30% (p=0.007) for PTCy and CNI-based, respectively. Moreover, the 2-year overall survival, progression-free survival and GVHD-free, relapse-free survival were all significantly better in the PTCy group compared with the CNI-based group: 85% versus 72% (p=0.005), 72% versus 53% (p<0.001), and 59% versus 31% (p<0.001), respectively. In multivariable analysis, PTCy was associated with a lower risk of chronic and extensive chronic GVHD, reduced relapse, and better OS, PFS, and GRFS compared to the CNI-based platform. Our findings suggest that PTCy as GVHD prophylaxis offers more favorable outcomes compared to conventional CNI-based prophylaxis in adult patients with HL undergoing HSCT from HLA-matched donors.

2.
Transplant Cell Ther ; 30(5): 538.e1-538.e10, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38331195

RESUMO

Cytomegalovirus (CMV) reactivations cause significant morbidity in allogeneic hematopoietic stem cell transplantation (HSCT) recipients. Graft-versus-host disease (GVHD) prophylaxis with post-transplantation cyclophosphamide (PTCy) is associated with an increased risk of CMV infections. Data are limited comparing HSCT with PTCy performed from matched sibling donors (MSDs), matched unrelated donors (MUDs), and haploidentical (Haplo) donors. In the present study, we aimed to characterize CMV reactivation and recurrence in patients with hematologic malignancies undergoing HSCT from MSD, MUD, and Haplo donors using PTCy as GVHD prophylaxis in the pre-letermovir era. We also analyzed risk factors of CMV reactivation, including GVHD as a time-dependent variable, on the incidence and mortality associated with CMV infections. We analyzed CMV reactivation in patients undergoing HSCT from 160 MSDs, 124 MUDs, and 82 Haplo donors from a single institution. Uniform GVHD prophylaxis with PTCy, sirolimus, and mycophenolate mofetil was given irrespective of donor type. Overall, 46% of patients had at least 1 CMV reactivation. The 1-year cumulative incidence of CMV infection was 39% for MSD, 44% for MUD, and 62% for Haplo donors (P < .001), with 96% of reactivations occurring before day +100. Multivariate analysis identified factors associated with the first CMV reactivation, including Haplo donor, positive recipient CMV serology, older patient age, and grade II-IV acute GVHD. The 1-year cumulative incidence of second reactivation from HSCT was 13%. Recipient CMV seropositivity, older patient age, and grade II-IV acute GVHD, but not type of donor, were identified as adverse factors for second CMV reactivation in multivariate analysis. The 1-year cumulative incidence of a third reactivation post HSCT was 4.4%. Ten cases of CMV disease were recorded, with no attributable deaths. Nevertheless, the risk for nonrelapse mortality was greater for patients who experienced CMV reactivation in multivariate time-dependent Cox model analysis. CMV reactivation is frequent in HSCT with PTCy in patients not receiving letermovir prophylaxis. Identified risk factors include the use of a Haplo donor, recipient CMV seropositivity, and grade II-IV acute GVHD. The prevalence of recurrent CMV reactivations is a noteworthy issue, especially after acute GVHD, warranting trials of secondary prophylaxis strategies.


Assuntos
Ciclofosfamida , Infecções por Citomegalovirus , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Ativação Viral , Humanos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Ativação Viral/efeitos dos fármacos , Ciclofosfamida/uso terapêutico , Ciclofosfamida/efeitos adversos , Doença Enxerto-Hospedeiro/prevenção & controle , Infecções por Citomegalovirus/prevenção & controle , Infecções por Citomegalovirus/epidemiologia , Transplante Homólogo/efeitos adversos , Citomegalovirus/imunologia , Citomegalovirus/efeitos dos fármacos , Idoso , Adulto Jovem , Doadores de Tecidos , Adolescente , Transplante Haploidêntico/efeitos adversos , Fatores de Risco , Imunossupressores/uso terapêutico , Imunossupressores/efeitos adversos , Neoplasias Hematológicas/terapia , Doadores não Relacionados , Antígenos HLA/imunologia , Irmãos
3.
Foods ; 13(2)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38254551

RESUMO

The food industry is looking for substitutes for sucrose in food items due to the excessive consumption of products with added sugar and the demand for healthier products. Alternative natural sweeteners can help achieve this goal. Different types of low-fat yoghurts (1% fat), with low-protein and high-protein levels (3% and 4.5-6.5% protein, respectively), were produced using alternative natural sweeteners. The low-protein yoghurts were made with stevia (0.03% w/w) or agave syrup (4.5% w/w). The high-protein yoghurts were made with stevia (0.04% w/w), xylitol (6% w/w) or honey (6% w/w). Sucrose (6% w/w) was used as a control in both trials. pH and titratable acidity, CIEL*a*b* color parameters, syneresis index, rheology and the texture profile of the low-fat yoghurts were evaluated over refrigerated storage. All products underwent sensory evaluation by an untrained panel. The high-protein yoghurts were found to be more acidic (>1% as lactic acid), had a lower syneresis index (between 2.1 and 16.2%) and a better consistency (stronger gel structure) than the low-protein yoghurts. In terms of rheological parameters, stevia-sweetened yoghurts scored higher than the other sweetened yoghurts, showing a better gel structure. The different sweeteners tested did not significantly affect the sensory properties of the yoghurts, although the high-protein yoghurts scored higher for most of the attributes evaluated. Overall, consumers preferred stevia-sweetened yoghurts to yoghurts sweetened with sucrose or agave for the low-protein yoghurts. Of the tested formulations, those containing high protein with the alternative natural sweetener xylitol received higher scores in all attributes. These results reveal the potential of the tested natural sweeteners as sucrose substitutes, while contributing to improving the nutritional value of yoghurts.

4.
Molecules ; 28(11)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37298931

RESUMO

With great cultural significance, spirits and distillate beverages constitute an important niche market in Europe. The development of new food products, particularly for the functionalization of these beverages, is increasing exponentially. The present work aimed to develop a new wine spirit beverage aged with almond shells and flowers of P. tridentatum for further characterization of bioactive and phenolic compounds, coupled with a sensorial study to evaluate the acceptance of this new product by the market. Twenty-one phenolic compounds were identified, mainly isoflavonoids and O- and C-glycosylated flavonoids, especially in P. tridentatum flowers, indicating that it is a highly aromatizing agent. The developed liqueur and wine spirits (almonds and flowers) showed distinct physicochemical properties, with the last two samples showing greater appreciation and purchase intention by consumers due to their sweetness and smoothness. The most promising results were found for the carqueja flower, which should be further investigated in an industrial context to contribute to its valorization in its regions of origin, such as Beira Interior and Trás-os-Montes (Portugal).


Assuntos
Genista , Prunus dulcis , Fenóis/química , Flavonoides , Genista/química , Antioxidantes/química
5.
Foods ; 12(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36673423

RESUMO

Small ruminant dairy products are common in some Mediterranean countries, in the Middle East and Africa, and can play a particular role in the development of rural areas. Butter has been the object of few research studies aimed at evaluating its potential as a vehicle for probiotic microorganisms. Moreover, the recovery of fermented buttermilk with functional properties can be considered an excellent opportunity to value this dairy byproduct. Therefore, the purpose of the present work was to develop different sheep butters and respective buttermilks after cream fermentation by: (1) a mesophilic aromatic starter (A); (2) a kefir culture (K); and (3) a mixture of probiotic bacteria (P). The butters and buttermilk produced with fermented cream were compared with non-fermented sweet cream (S) butter or buttermilk, respectively, regarding their physicochemical, microbiological and sensory characteristics. The adjusted production (%, w/v) obtained for butter were: S (44.48%), A (36.82%), K (41.23%) and P (43.36%). S, A and K butters had higher solids, fat and ashes contents than P butter. The probiotic butter had a total fat of ca. 75% (w/w), below the legal limits, while all others had fat levels above 81.5%. In all samples, the pH decreased and the acidity increased over 90 days of refrigerated storage. These variations were more evident in the P butter, which agrees with the highest lactic acid bacteria counts found in this sample. Differences in color between samples and due to storage time were also observed. In general, the butter samples tended to become darker and yellower after the 60th day of storage. Texture analysis showed comparable results between samples and greater hardness was observed for the P butter, most probably due to its higher relative saturated fatty acids content (66.46% compared to 62−64% in S, A and K butters). Regarding rheological properties, all butters showed pseudoplastic behavior, but butter P had the lowest consistency index (249 kPa.sn−1). The probiotic butter and the corresponding buttermilk had viable cell counts greater than 7 Log CFU/g, indicating their suitability as probiotic carriers. All products were well accepted by consumers and small, but non-significant, differences (p > 0.05) were observed in relation to the sensory parameters evaluated. In general, it can be concluded that the use of adequate starter cultures can allow the production of innovative and potentially healthier products, alongside the valorization of dairy byproducts, improving the income of small-scale producers.

6.
Int J Food Sci ; 2022: 9189575, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35898417

RESUMO

The nutraceutical properties of Punica granatum L. are not restricted to the edible portion of the fruit but also to the peels and seeds, flowers, leaves, and tree bark. The recovery and valorization of the peel and seeds (ca. 50% of the whole fruit), besides the positive environmental impact, can be viewed as a source of natural bioactive compounds. Thus, the bioactive properties of extracts of pomegranate peel and seeds from Acco and Wonderful known cultivars, as well as of the novel Big Full cultivar, were evaluated. The dried and ground pomegranate by-products were submitted to a conventional solid/liquid extraction with ethanol/water mixtures (0%, 25%, 50%, and 75% of EtOH, v/v). The obtained extracts were characterized in terms of total phenolic compounds (TPC), total flavonoids (TF), and antioxidant activity (AA), determined by the DPPH radical scavenging activity and expressed as IC50 (half maximum inhibitory concentration). With the exception of the Acco cultivar, the extraction yield (EY) was higher for peels, whose extracts showed higher TPC, TF, and IC50 (lower AA). The extracts obtained from the by-products of the Big Full cultivar had a statistically higher overall bioactive potential (TPC: 0.36 mg GAE/mg extract; TF: 0.031 mg CATE/mg extract; IC50: 0.51 mg/mL) compared to the other two studied cultivars. Furthermore, the EY was enhanced by solvents richer in ethanol (50-75%), allowing obtaining extracts richer in TPC and TF with higher AA. Finally, it was shown that EY combined with bioactive data allowed a satisfactory principal component unsupervised differentiation of the pomegranate extracts according to the type of by-product used.

7.
J Funct Biomater ; 13(2)2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35645271

RESUMO

Tissue engineering using scaffolds is a promising strategy to repair damaged articular cartilage, whose self-repair is inefficient. Cellulose properties have been recognized for their application in the biomedical field. The aim of this study was to fabricate and characterize novel scaffolds based on poly(ɛ-caprolactone) (PCL) and sustainable cellulose. Thus, the performance of corncob-derived cellulose (CC) in scaffolds as an alternative to wood cellulose (WC) was also investigated to reduce the environmental footprint. Two concentrations of CC in scaffolds were tested, 1% and 2% (w/w), and commercial WC using the same concentrations, as a control. Morphologically, all the developed scaffolds presented pore sizes of ~300 µm, 10 layers, a circular shape and well-dispersed cellulose. Thus, all of these characteristics and properties provide the manufactured scaffolds suitable for use in cartilage-replacement strategies. The use of 2% CC results in higher porosity (54.24%), which promotes cell infiltration/migration and nutrient exchange, and has similar mechanical properties to WC. As for the effects of enzymatic degradation of the scaffolds, no significant changes (p > 0.05) were observed in resistance over time. However, the obtained compressive modulus of the scaffold with 2% CC was similar to that of WC. Overall, our results suggest that the integration of 2% corncob cellulose in PCL scaffolds could be a novel way to replace wood-cellulose-containing scaffolds, highlighting its potential for cartilage-replacement strategies.

8.
Acta Med Port ; 35(12): 908-912, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-35635375

RESUMO

Serratia marcescens is a rarely implicated agent in endocarditis. We describe a case of a patient that underwent aortic and mitral valve replacement for Streptococcus agalactiae endocarditis. Four months later, he was readmitted with an ischemic stroke and fever. Physical examination and repetitive transthoracic echocardiogram were unremarkable. The initial blood cultures were negative. Due to sustained fever, vancomycin, gentamicin and piperacillin-tazobactam were initiated. On subsequent blood cultures, Serratia marcescens was isolated and antibiotics switched to ertapenem and gentamicin. In addition to cerebral emboli, a splenic embolus was found. The PET/CT revealed an abnormal hypercaptation in the mitral bioprosthesis. The patient was treated for six weeks. There are no current specific recommendations regarding the treatment of Serratia marcescens endocarditis. It is widely accepted that treatment should be prolonged and include a combination of antimicrobial agents. Morbidity and mortality are high, particularly when there's the need for surgical replacement. In this case, however, the patient ended-up only requiring medical treatment due to the favourable response.


A Serratia marcescens é um agente raro de endocardite. Descrevemos o caso de um doente submetido a substituição das válvulas aórtica e mitral por endocardite causada por Streptococcus agalactiae. Quatro meses após, é readmitido por evento cerebral isquémico e febre. Ao exame objetivo não evidenciava alterações e os ecocardiogramas transtorácicos eram normais. As hemoculturas colhidas à admissão foram estéreis. O doente manteve-se febril, iniciando-se empiricamente vancomicina, gentamicina e piperacilina-tazobactam. Após isolamento de Serratia marcescens em hemoculturas subsequentes, a antibioterapia foi ajustada para ertapenem e gentamicina. Para além de um êmbolo cerebral, foi encontrada embolia esplénica e hipercaptação anormal na prótese mitral biológica em PET. Foi efetuado tratamento durante seis semanas. Não existem recomendações específicas sobre o tratamento de endocardite por Serratia marcescens, mas deve ser prolongado e com terapêutica combinada. A morbimortalidade é elevada, sobretudo quando há necessidade de cirurgia. Neste caso, a evolução clínica favorável do doente permitiu o tratamento médico exclusivo.


Assuntos
Endocardite Bacteriana , Endocardite , Masculino , Humanos , Serratia marcescens , Endocardite Bacteriana/diagnóstico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Gentamicinas
9.
Foods ; 11(7)2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35407079

RESUMO

Pomegranate by-products can be an asset to the food industry due to the richness in bioactive and antimicrobial compounds. This work studied the influence of conventional solvent and sonication-assisted extraction methods on the bioactive profile, antimicrobial properties, and phytotoxicity effect of the peels and seeds extracts from Acco, Big Full, and Wonderful pomegranate cultivars. The bioactive composition of the extracts was evaluated for the content of total phenolics, total flavonoids, and antioxidant activity (expressed as the half-maximal inhibitory concentration-IC50) by spectrophotometric methods, while the tannins were determined by titration and the anthocyanins were estimated by the pH-differential method. For the evaluation of the antimicrobial activity, the disk diffusion method of Kirby-Bauer was adapted through inhibition halos against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus cereus, and Yarrowia lipolytica. The extracts' phytotoxicity was evaluated in vitro on garden-cress seeds. Extracts from conventional extraction were richer in total phenolics, expressed as gallic acid equivalents (0.16-0.73 mg GAE/mg extract), while those from sonication-assisted extraction had higher contents of total flavonoids, expressed as catechin equivalents (0.019-0.068 mg CATE/mg extract); anthocyanins, expressed as cyanidin-3-glucoside (0.06-0.60 µg C3G/mg, dry basis); and antioxidant activity (IC50, 0.01-0.20 mg/mL). All extracts were more effective against Gram-positive bacteria and yeasts than Gram-negative bacteria. In general, the sonication-assisted extracts led to higher inhibition halos (8.7 to 11.4 mm). All extracts presented phytotoxicity against garden-cress seeds in the tested concentrations. Only the lowest concentration (0.003 mg/mL) enabled the germination of seeds and root growth, and the sonication-assisted extracts showed the highest Munoo-Liisa vitality index (51.3%). Overall, sonication-assisted extraction obtained extracts with greater bioactive and antimicrobial potential and less phytotoxicity.

10.
J Dairy Sci ; 104(2): 1504-1517, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33309377

RESUMO

Fresh unripened curd cheese has long been a well-known Eastern European artisanal dairy product; however, due to possible cross-contamination from manual production steps, high moisture content (50-60%), and metabolic activity of present lactic acid bacteria, the shelf life of curd cheese is short (10-20 d). Therefore, the aim of this study was to improve the shelf life of Eastern European acid-curd cheese by applying an antimicrobial protein-based (5%, wt/wt) edible coating. The bioactive edible coating was produced from liquid whey protein concentrate (a cheese production byproduct) and fortified with 0.3% (wt/wt, solution basis) Chinese cinnamon bark (Cinnamomum cassia) CO2 extract. The effect of coating on the cheese was evaluated within package-free (group 1) and additionally vacuum packaged (group 2) conditions to represent types of cheeses sold by small and big scale manufacturers. The cheese samples were examined over 31 d of storage for changes of microbiological (total bacterial count, lactic acid bacteria, yeasts and molds, coliforms, enterobacteria, Staphylococcus spp.), physicochemical (pH, lactic acid, protein, fat, moisture, color change, rheological, and sensory properties). The controlled experiment revealed that in group 1, applied coating affected appearance and color by preserving moisture and decreasing growth of yeasts and molds during prolonged package-free cheese storage. In group 2, coating did not affect moisture, color, or texture, but had a strong antimicrobial effect, decreasing the counts of yeasts and molds by 0.79 to 1.55 log cfu/g during 31 d of storage. In both groups, coating had no effect on pH, lactic acid, protein, and fat contents. Evaluated sensory properties (appearance, odor, taste, texture, and overall acceptability) of all samples were similar, indicating no effect of the coating on the flavor of curd cheese. The edible coating based on liquid whey protein concentrate with the incorporation of cinnamon extract was demonstrated to efficiently extend the shelf life of perishable fresh curd cheese, enhance its functional value, and contribute to a more sustainable production process.


Assuntos
Anti-Infecciosos/farmacologia , Queijo/normas , Cinnamomum zeylanicum/química , Contaminação de Alimentos/prevenção & controle , Lactobacillales/metabolismo , Extratos Vegetais/farmacologia , Proteínas do Soro do Leite/farmacologia , Animais , Dióxido de Carbono/farmacologia , Queijo/microbiologia , Filmes Comestíveis , Armazenamento de Alimentos , Casca de Planta/química , Extratos Vegetais/química , Paladar
11.
J Sci Food Agric ; 101(2): 555-563, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32672836

RESUMO

BACKGROUND: In Southern European countries, whey cheeses are normally produced with ovine or caprine whey. Cow's cheese whey can also be used, although the whey cheese yield is low (2-3%, w/v) which discourages its use. In the present study, bovine cheese whey was concentrated by ultrafiltration for the production of four types of whey cheeses (Requeijão): conventional, without any addition (WC); with 10% (w/w) addition of cream (WCC); with cream fermented with Kefir culture (WCCK); and with cream fermented with Bifidobacterium sp. culture (WCCBB12). RESULTS: Whey cheeses with cream presented lower protein content (330-360 g kg-1 , dry basis) and higher levels of total solids (220-250 g kg-1 ) and fat (300-330 g kg-1 , dry basis) than WC. C16:0 and C18:1 were the most abundant fatty acids present, with 31% and 38%, respectively. The small differences found concerning instrumental determination of colour and texture were not perceived by panelists. However, the presence of Kefir and probiotics decreased the elastic modulus (G') of the samples, as well as their viscosity. Fermentation with Kefir presented the highest counts of lactic acid bacteria (7 logUFC g-1 ). However, after 14 days of refrigerated storage, the counts of yeasts and moulds reached 6 logUFC g-1 in all products, indicating the need for appropriate packaging solutions. CONCLUSION: Ultrafiltration of bovine whey allows for the efficient production of bovine whey cheeses. The addition of cream fermented with Kefir or BB12 appears to be an efficient methodology to incorporate Kefir or probiotic bacteria in Requeijão, improving its nutritional and sensory characteristics, alongside the potential for the extension of its shelf-life. © 2020 Society of Chemical Industry.


Assuntos
Bifidobacterium/metabolismo , Queijo/microbiologia , Microbiologia de Alimentos/métodos , Kefir/microbiologia , Probióticos/metabolismo , Ultrafiltração/métodos , Soro do Leite/microbiologia , Animais , Bovinos , Queijo/análise , Módulo de Elasticidade , Fermentação , Kefir/análise , Lactobacillales/crescimento & desenvolvimento , Lactobacillales/metabolismo , Leite/química , Leite/microbiologia , Probióticos/análise , Ovinos , Soro do Leite/química
12.
Bioresour Bioprocess ; 8(1): 25, 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38650204

RESUMO

Considering the expected increasing demand for cellulose fibers in the near future and that its major source is wood pulp, alternative sources such as vegetable wastes from agricultural activities and agro-food industries are currently being sought to prevent deforestation. In the present study, cellulose was successfully isolated from six agroindustrial residues: corncob, corn husk, grape stalk, pomegranate peel, marc of strawberry-tree fruit and fava pod. Cellulose fibers were characterized by Fourier-transform infrared spectroscopy, thermogravimetric analysis, stereomicroscopy and scanning electron microscopy (SEM). Despite the evident morphological differences among the extracted celluloses, results revealed similar compositional and thermal properties with the wood-derived commercial microcrystalline cellulose used as a control. Trace amounts of lignin or hemicellulose were detected in all cellulose samples, with the exception of corncob cellulose, that exhibited the greatest extraction yield (26%) and morphological similarities to wood-derived microcrystalline cellulose, visible through SEM. Furthermore, corncob cellulose was found to have thermal properties (TOnset of 307.17 °C, TD of 330.31 °C, and ΔH of 306.04 kJ/kg) suitable for biomedical applications.

13.
Materials (Basel) ; 13(17)2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32887321

RESUMO

Valorization of food industry waste and plant residues represents an attractive path towards obtaining biodegradable materials and achieving "zero waste" goals. Here, melanin was isolated from watermelon (Citrullus lanatus) seeds and used as a modifier for whey protein concentrate and isolate films (WPC and WPI) at two concentrations (0.1% and 0.5%). The modification with melanin enhanced the ultraviolet (UV) blocking, water vapor barrier, swelling, and mechanical properties of the WPC/WPI films, in addition to affecting the apparent color. The modified WPC/WPI films also exhibited high antioxidant activity, but no cytotoxicity. Overall, the effects were melanin concentration-dependent. Thus, melanin from watermelon seeds can be used as a functional modifier to develop bioactive biopolymer films with good potential to be exploited in food packaging and biomedical applications.

14.
Foods ; 9(8)2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32751419

RESUMO

In the following study, three different dairy by-products, previously concentrated by ultrafiltration (UF), were used as ingredients in the production of reduced-fat (RF) washed curd cheeses in order to improve their characteristics. Conventional full-fat (FF) cheeses (45% fat, dry basis (db)) and RF cheeses (20-30% fat, db) were compared to RF cheeses produced with the incorporation of 5% concentrated whey (RF + CW), buttermilk (RF + CB) or sheep second cheese whey (RF + CS). Protein-to-fat ratios were lower than 1 in the FF cheeses, while RF cheeses ranged from 1.8 to 2.8. The tested by-products performed differently when added to the milk used for cheese production. The FF cheese showed a more pronounced yellow colour after 60 and 90 days of ripening, indicating that fat plays an important role regarding this parameter. As far as the texture parameters are concerned, after 60 days of ripening, RF cheeses with buttermilk presented similar results to FF cheeses for hardness (5.0-7.5 N) and chewiness (ca. 400). These were lower than the ones recorded for RF cheeses with added UF concentrated whey (RF + CW) and second cheese whey (RF + CS), which presented lower adhesiveness values. RF cheeses with 5% incorporation of buttermilk concentrated by UF presented the best results concerning both texture and sensory evaluation.

15.
Science ; 367(6478): 671-676, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-32029625

RESUMO

Magnetoelectric (ME) materials combine magnetic and electric polarizabilities in the same phase, offering a basis for developing high-density data storage and spintronic or low-consumption devices owing to the possibility of triggering one property with the other. Such applications require strong interaction between the constitutive properties, a criterion that is rarely met in classical inorganic ME materials at room temperature. We provide evidence of a strong ME coupling in a paramagnetic ferroelectric lanthanide coordination complex with magnetostrictive phenomenon. The properties of this molecular material suggest that it may be competitive with inorganic magnetoelectrics.

16.
Rheumatology (Oxford) ; 59(5): 1137-1147, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31600398

RESUMO

OBJECTIVES: Patient global assessment (PGA) is purported to add the patient's perspective in the composite measures of RA. However, PGA is not standardized and it is not known whether patients' interpretation of the measure is consistent with its intended purpose. This study aimed to explore difficulties experienced by patients with RA in completing PGA, and to assess the impact of a structured explanation in improving its validity and reliability. METHODS: This was a mixed methods study, using interviews, focus groups and PGA data. During interviews, patients (convenience sample, n = 33) completed three often-used PGA formulations. Then a nurse provided structured explanation about what PGA is and why it is used. After further discussion, patients completed one PGA version again. Interviews were recorded, transcribed and analysed using inductive thematic analysis. We compared PGA scores pre- and post-explanation (Wilcoxon signed-ranks) and the proportion of patients achieving RA remission with PGA ⩽1 (McNemar's tests). RESULTS: Three themes emerged: understanding the meaning of PGA, the purpose of PGA and measurement difficulties. The difficulties caused systematic errors in PGA completion such as marking higher when feeling well, marking near the centre or away from zero. The structured explanation was helpful. Following the explanation, the median PGA score decreased from 3.0 to 2.1 cm, and the proportion of non-remission solely due to PGA >1 from 52% to 41%; none of these changes was statistically significant. CONCLUSION: Many patients have difficulties in completing PGA. Standardization of PGA and a structured explanation may improve its clarity, validity and reliability.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/epidemiologia , Saúde Global , Medidas de Resultados Relatados pelo Paciente , Adulto , Artrite Reumatoide/diagnóstico , Feminino , Grupos Focais , Humanos , Incidência , Internacionalidade , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Medição de Risco , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Resultado do Tratamento
17.
J Dairy Sci ; 102(9): 7838-7848, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31255280

RESUMO

Frozen yogurt is a type of dairy product that is considered to be a more healthful alternative to conventional ice cream due to its lower fat content and the presence of viable lactic acid bacteria. Lactose-free products are a growing trend in the dairy industry, and lactose-free yogurts and ice creams can both be found on the market. However, lactose-free frozen yogurt has not yet reached the market. In this study, we aimed to investigate the effect of adding κ-carrageenan (0.05, 0.1, and 0.15%) and corn starch (1, 2, and 3%) on acidity, texture, viscosity, overrun, melting properties, color attributes, and sensory characteristics of lactose-free frozen yogurts. Lactose was reduced by enzymatic hydrolysis during the fermentation process. The effectiveness of the hydrolysis was measured by HPLC, and lactose was reduced to 0.05% after 80 min of incubation with the enzyme. The addition of stabilizers did not change overrun and melting properties of frozen yogurt, but it did affect pH, titratable acidity, and color parameters. The product with 0.15% κ-carrageenan had the highest hardness and stickiness values. Moreover, κ-carrageenan had a positive effect on sensory attractiveness of lactose-free frozen yogurt, and it reduced the coarse texture in comparison with the control without stabilizers. A lactose-free frozen yogurt with good quality and nutritional characteristics was produced, particularly with the use of κ-carrageenan as stabilizer.


Assuntos
Lactobacillus delbrueckii/metabolismo , Streptococcus thermophilus/metabolismo , Iogurte/análise , Carragenina/química , Excipientes/química , Fermentação , Alimentos Congelados , Concentração de Íons de Hidrogênio , Hidrólise , Lactose/análise , Reologia , Amido/química , Viscosidade , Iogurte/microbiologia , Zea mays
18.
Chemistry ; 24(13): 3251-3262, 2018 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-29283203

RESUMO

Reports showing that the copper concentration is considerably higher in neoplasms than in normal tissues prompted the need to develop selective copper chelators. We disclosed recently that some N-linked tetrazole-saccharinates bind selectively to copper, forming complexes that are highly cytotoxic towards cancer cells. Because tetrazole-saccharinates are photolabile, due to the photoreactivity of tetrazoles, we proposed thiadiazolyl-saccharinates as an alternative. Herein we describe the synthesis, structure, and monomeric photochemistry of a sulphanyl-bridged thiadiazolyl-saccharinate, 3-[(5-methyl-1,3,4-thiadiazol-2-yl)sulphanyl]-1,2-benzothiazole 1,1-dioxide (MTSB). The monomeric structure, charge density analysis, and characteristic infrared spectrum of MTSB were investigated theoretically, using quantum chemical calculations, and also experimentally, using matrix-isolation infrared spectroscopy. The crystal structure was investigated by combining X-ray crystallography with infrared and Raman spectroscopies. Results show that the structure of isolated MTSB is similar to that found in the crystal, with an S⋅⋅⋅N interaction clearly contributing to the structure of the molecule and of the crystal. Matrix irradiation revealed a high photostability of MTSB, compared to parent tetrazole-saccharinates and to the 5-methyl-1,3,4-thiadiazole building block, emphasizing the photostabilizing effect of the saccharyl system. Finally, in vitro toxicity assays of MTSB showed a copper concentration-dependent toxicity against cancer cells, without affecting normal cells. In particular, MTSB was most effective towards the hepatic (HepG2), neuroblastoma (SH-SY5), and lymphoma cell lines (U937). Thus, MTSB represents a promising lead for cancer chemotherapy based on chelating agents.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Benzotiazóis/síntese química , Benzotiazóis/farmacologia , Compostos Heterocíclicos de Anel em Ponte/síntese química , Compostos Heterocíclicos de Anel em Ponte/farmacologia , Sacarina/análogos & derivados , Sacarina/síntese química , Sacarina/farmacologia , Compostos de Enxofre/síntese química , Compostos de Enxofre/farmacologia , Tiadiazóis/síntese química , Tiadiazóis/farmacologia , Antineoplásicos/química , Benzotiazóis/química , Compostos Heterocíclicos de Anel em Ponte/química , Humanos , Estrutura Molecular , Sacarina/química , Relação Estrutura-Atividade , Compostos de Enxofre/química , Tiadiazóis/química
19.
Acta Sci Pol Technol Aliment ; 16(2): 171-179, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28703957

RESUMO

BACKGROUND: Nowadays, consumer demand is driving better and more nutritious dairy products. Changing from traditional to new lactose-free products poses technological challenges for the food industry in order to maintain or improve their food characteristics and consumer preferences. METHODS: This study investigates the production of lactose-free frozen yogurt by enzymati- cally hydrolysis of lactose, and its influence on the final product characteristics. In the case of lactose-free products, commercial Ha-lactase® was used for hydrolysis, and the reaction occurred simultaneously with fermentation. The effect of lactose hydrolysis on the physicochemical properties, texture, viscosity, overrun and sensory attributes in the final product was investigated. RESULTS: After yogurt maturation, the acidity of the lactose-free product was significantly higher than in the control, suggesting that breaking down lactose enhances the fermentation process. Lactose-free frozen yogurt had significantly lower hardness and stickiness and higher viscosity than control frozen yogurt. Moreover, lactose hydrolysis promoted a smooth and creamy consistency, whereas in the case of conventional prod- ucts a coarse structure, due to the presence of large ice crystals, was identified. Hydrolysis of lactose also improved the sweetness and brightness of frozen yogurt. The improved textural properties of lactose-free product results from the fact that monosaccharides produced during lactose hydrolysis depress the freezing point of the mix, which enables product with softer structure and bigger resistance to ice recrystallization to be obtained. CONCLUSIONS: The study showed that lactose-free frozen yogurt may be used successfully for production of novel lactose-free frozen desserts. Lactose hydrolysis improves the texture and viscosity of the product,     as well as enhancing its sensory quality.


Assuntos
Fenômenos Químicos , Manipulação de Alimentos , Lactose/análise , Iogurte/análise , Comportamento do Consumidor , Fermentação , Microbiologia de Alimentos , Congelamento , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Lactobacillus delbrueckii , Valor Nutritivo , Streptococcus thermophilus , Paladar
20.
Nanotechnology ; 28(28): 285704, 2017 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-28643695

RESUMO

This work reports on highly fluorescent and superparamagnetic bimodal nanoparticles (BNPs) obtained by a simple and efficient method as probes for fluorescence analysis and/or contrast agents for MRI. These promising BNPs with small dimensions (ca. 17 nm) consist of superparamagnetic iron oxide nanoparticles (SPIONs) covalently bound with CdTe quantum dots (ca. 3 nm). The chemical structure of the magnetic part of BNPs is predominantly magnetite, with minor goethite and maghemite contributions, as shown by Mössbauer spectroscopy, which is compatible with the x-ray diffraction data. Their size evaluation by different techniques showed that the SPION derivatization process, in order to produce the BNPs, does not lead to a large size increase. The BNPs saturation magnetization, when corrected for the organic content of the sample, is ca. 68 emu g-1, which is only slightly reduced relative to the bare nanoparticles. This indicates that the SPION surface functionalization does not change considerably the magnetic properties. The BNP aqueous suspensions presented stability, high fluorescence, high relaxivity ratio (r 2/r 1 equal to 25) and labeled efficiently HeLa cells as can be seen by fluorescence analysis. These BNP properties point to their applications as fluorescent probes as well as negative T 2-weighted MRI contrast agents. Moreover, their potential magnetic response could also be used for fast bioseparation applications.

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