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1.
J Sci Food Agric ; 100(12): 4601-4611, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32419139

RESUMO

BACKGROUND: An innovative pilot-plant packaging was developed and evaluated for applying oregano essential oil (OEO) vapours in conditions of high vacuum for exploring the antimicrobial effect of essential oil vapours applied immediately before packaging of fish fillets. Farmed sea bream (Sparus aurata) fresh fillets have been used as a model for validating this new technology. These fillets, as a refrigerated product under modified atmosphere packaging (MAP), have a relatively short shelf life (12-14 days) mainly due to the fast microbial growth. The effects of conventional OEO dippings [pretreatment dipping (0.1% of OEO) of whole fish (T1) and filleted sea bream (T2)] were compared with the OEO application in vapour phase (67 µL L-1 ) under vacuum (5-10 hPa) immediately before MAP fillet packaging (T3). RESULTS: T3/T2 samples showed the lowest microbial growth after 28 days at 4 °C, with loads up to 1/2.6 log units for Enterobacteria/lactic acid bacteria compared to untreated samples. The initial trimethylamine nitrogen (TMA-N) content (2.6 mg kg-1 ) increased in T1 and T2/T3 samples by 9.6 and 6/7 units, respectively, after 28 days. Quality Index Method (QIM) better reflected the fish fillets shelf life than texture and colour measurements. The shelf life of T3/T2 samples was established in at least 28 days (4 °C), while the QIM threshold (6) was exceeded after 7/21 days in untreated/T1 fillets. CONCLUSION: The fish shelf life was extended with vapour OEO treatment using this new technology, similarly to OEO dipping treatment, according to QIM, corroborated by the microbial quality and TMA-N contents. © 2020 Society of Chemical Industry.


Assuntos
Produtos Pesqueiros/análise , Embalagem de Alimentos/métodos , Animais , Contagem de Colônia Microbiana , Enterobacteriaceae/crescimento & desenvolvimento , Produtos Pesqueiros/microbiologia , Embalagem de Alimentos/instrumentação , Conservação de Alimentos , Conservantes de Alimentos/análise , Armazenamento de Alimentos , Óleos Voláteis/análise , Origanum/química , Dourada/microbiologia
2.
Front Immunol ; 15: 1362995, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38596676

RESUMO

Introduction: Common Variable Immunodeficiency (CVID) patients are characterized by hypogammaglobulinemia and poor response to vaccination due to deficient generation of memory and antibody-secreting B cells. B lymphocytes are essential for the development of humoral immune responses, and mitochondrial function, hreactive oxygen species (ROS) production and autophagy are crucial for determining B-cell fate. However, the role of those basic cell functions in the differentiation of human B cells remains poorly investigated. Methods: We used flow cytometry to evaluate mitochondrial function, ROS production and autophagy processes in human naïve and memory B-cell subpopulations in unstimulated and stimulated PBMCs cultures. We aimed to determine whether any alterations in these processes could impact B-cell fate and contribute to the lack of B-cell differentiation observed in CVID patients. Results: We described that naïve CD19+CD27- and memory CD19+CD27+ B cells subpopulations from healthy controls differ in terms of their dependence on these processes for their homeostasis, and demonstrated that different stimuli exert a preferential cell type dependent effect. The evaluation of mitochondrial function, ROS production and autophagy in naïve and memory B cells from CVID patients disclosed subpopulation specific alterations. Dysfunctional mitochondria and autophagy were more prominent in unstimulated CVID CD19+CD27- and CD19+CD27+ B cells than in their healthy counterparts. Although naïve CD19+CD27- B cells from CVID patients had higher basal ROS levels than controls, their ROS increase after stimulation was lower, suggesting a disruption in ROS homeostasis. On the other hand, memory CD19+CD27+ B cells from CVID patients had both lower ROS basal levels and a diminished ROS production after stimulation with anti-B cell receptor (BCR) and IL-21. Conclusion: The failure in ROS cell signalling could impair CVID naïve B cell activation and differentiation to memory B cells. Decreased levels of ROS in CVID memory CD19+CD27+ B cells, which negatively correlate with their in vitro cell death and autophagy, could be detrimental and lead to their previously demonstrated premature death. The final consequence would be the failure to generate a functional B cell compartment in CVID patients.


Assuntos
Imunodeficiência de Variável Comum , Humanos , Espécies Reativas de Oxigênio/metabolismo , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo , Linfócitos B , Antígenos CD19/metabolismo , Autofagia , Mitocôndrias/metabolismo
3.
Plants (Basel) ; 12(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37836158

RESUMO

Plant essential oils (EOs) have an important ability to inhibit ethylene biosynthesis. Nevertheless, the effects of EOs on the key components of ethylene biosynthesis (l-aminocyclopropane-1-carboxylic (ACC) oxidase activity, ACC synthase activity, and ACC content) have not yet been thoroughly studied. Accordingly, this study focused on the effects of emitted EOs from active packaging (EO doses from 100 to 1000 mg m-2) on the key components of ethylene biosynthesis of blueberries and blackberries under several storage temperatures. Anise EO and lemon EO active packaging induced the greatest inhibitory effects (60-76%) on the ethylene production of blueberries and blackberries, respectively, even at high storage temperatures (22 °C). In terms of EO doses, active packaging with 1000 mg m-2 of anise EO or lemon EO led to the highest reduction of ethylene production, respectively. At 22 °C, the investigated EO active packing reduced the activities of ACC synthase and ACC oxidase up to 50%. In order to minimise ethylene biosynthesis in blueberries and blackberries when they are stored even under improper temperature scenarios at high temperatures, this EO active packaging is a natural and efficient technological solution.

4.
Plants (Basel) ; 12(19)2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37836143

RESUMO

Essential oils (EOs) extracted from plants have a high potential to reduce ethylene biosynthesis, although their effects have not been deeply studied yet on the key components of the ethylene biosynthesis pathway: l-aminocyclopropane-1-carboxylic (ACC) oxidase activity, ACC synthase activity, and ACC content. Hence, the present study aimed to elucidate the effects of released EOs from active packaging (with different EO doses ranging from 100 to 1000 mg m-2) on the ethylene biosynthesis key components of broccoli and tomato under different storage temperature scenarios. The largest ethylene inhibitory effects on broccoli and tomatoes were demonstrated by grapefruit EO and thyme essential EO (up to 63%), respectively, which were more pronounced at higher temperatures. Regarding EO doses, active packaging with a thyme EO dose of 1000 mg m-2 resulted in the strongest reduction (33-38%) of ethylene production in tomatoes. For broccoli, identical results were shown with a lower grapefruit EO dose of 500 mg m-2. The studied EO-active packaging decreased ACC synthase and ACC oxidase activities by 40-50% at 22 °C. Therefore, this EO-active packaging is a natural and effective technology to reduce ethylene biosynthesis in broccoli and tomatoes when they are stored, even in unsuitable scenarios at high temperatures.

5.
Foods ; 13(1)2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38201075

RESUMO

According to the Codex Alimentarius, a food additive is any substance that is incorporated into a food solely for technological or organoleptic purposes during the production of that food. Food additives can be of synthetic or natural origin. Several scientific evidence (in vitro studies and epidemiological studies like the controversial Southampton study published in 2007) have pointed out that several synthetic additives may lead to health issues for consumers. In that sense, the actual consumer searches for "Clean Label" foods with ingredient lists clean of coded additives, which are rejected by the actual consumer, highlighting the need to distinguish synthetic and natural codded additives from the ingredient lists. However, this natural approach must focus on an integrated vision of the replacement of chemical substances from the food ingredients, food contact materials (packaging), and their application on the final product. Hence, natural plant alternatives are hereby presented, analyzing their potential success in replacing common synthetic emulsifiers, colorants, flavorings, inhibitors of quality-degrading enzymes, antimicrobials, and antioxidants. In addition, the need for a complete absence of chemical additive migration to the food is approached through the use of plant-origin bioactive compounds (e.g., plant essential oils) incorporated in active packaging.

6.
Microbiology (Reading) ; 158(Pt 9): 2384-2398, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22723286

RESUMO

Non-typable Haemophilus influenzae (NTHi) is a common commensal of the human nasopharynx, but causes opportunistic infection when the respiratory tract is compromised by infection or disease. The ability of NTHi to invade epithelial cells has been described, but the underlying molecular mechanisms are poorly characterized. We previously determined that NTHi promotes phosphorylation of the serine-threonine kinase Akt in A549 human lung epithelial cells, and that Akt phosphorylation and NTHi cell invasion are prevented by inhibition of phosphoinositide 3-kinase (PI3K). Because PI3K-Akt signalling is associated with several host cell networks, the purpose of the current study was to identify eukaryotic molecules important for NTHi epithelial invasion. We found that inhibition of Akt activity reduced NTHi internalization; differently, bacterial entry was increased by phospholipase Cγ1 inhibition but was not affected by protein kinase inhibition. We also found that α5 and ß1 integrins, and the tyrosine kinases focal adhesion kinase and Src, are important for NTHi A549 cell invasion. NTHi internalization was shown to be favoured by activation of Rac1 guanosine triphosphatase (GTPase), together with the guanine nucleotide exchange factor Vav2 and the effector Pak1. Also, Pak1 might be associated with inactivation of the microtubule destabilizing agent Op18/stathmin, to facilitate microtubule polymerization and NTHi entry. Conversely, inhibition of RhoA GTPase and its effector ROCK increased the number of internalized bacteria. Src and Rac1 were found to be important for NTHi-triggered Akt phosphorylation. An increase in host cyclic AMP reduced bacterial entry, which was linked to protein kinase A. These findings suggest that NTHi finely manipulates host signalling molecules to invade respiratory epithelial cells.


Assuntos
Endocitose , Células Epiteliais/microbiologia , Haemophilus influenzae/patogenicidade , Integrinas/metabolismo , Microtúbulos/metabolismo , Fosfotransferases/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Linhagem Celular , Humanos
7.
Diagnostics (Basel) ; 12(3)2022 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-35328252

RESUMO

Autoantibody detection is the cornerstone of autoimmune liver diseases (AILD) diagnosis. Standardisation of working algorithms among autoimmunity laboratories, as well as being aware of the sensitivity and specificity of various commercial techniques in daily practice, are still necessary. The aim of this nationwide study is to report the results of the 2020 Autoimmunity Workshop organised by the Autoimmunity Group of the Spanish Society of Immunology and to provide useful information to clinicians and laboratory specialists to improve the management of autoantibody detection in AILD diagnoses. Serum samples from 17 patients with liver diseases were provided by the organisers of the 2020 Autoimmunity Workshop and were subsequently analysed by the 40 participating laboratories. Each laboratory used different techniques for the detection of autoantibodies in each patients' serum sample, according to their working algorithm. Thus, almost 680 total complete patient reports were obtained, and the number of results from different autoantibody detection techniques was >3000. Up to eight different working algorithms were employed, including indirect immunofluorescence assays (IFA) and antigen-specific techniques (AgST). The IFA of HEp-2 cells was more sensitive than IFA of rat triple tissue for the study of anti-nuclear autoantibodies (ANA) associated with AILD. The IFA of a human neutrophil study for the analysis of anti-neutrophil cytoplasmic autoantibodies was not carried out systemically in all patients, or by all laboratories. AgSTs were the most sensitive methods for the detection of anti-smooth muscle/F-actin, soluble liver antigen, liver cytosol-1, M2-mitochondrial autoantibodies, and ANA associated with primary biliary cholangitis. The main differences in AMA detection were due to patients with autoantibodies against the non-dominant epitope of pyruvate dehydrogenase complex. Given that they are complementary, IFA and AgST should be performed in parallel. If there is high suspicion of AILD, AgST should always be performed.

8.
Microbiology (Reading) ; 157(Pt 1): 234-250, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20929955

RESUMO

Nontypable Haemophilus influenzae (NTHi) is a Gram-negative, non-capsulated human bacterial pathogen, a major cause of a repertoire of respiratory infections, and intimately associated with persistent lung bacterial colonization in patients suffering from chronic obstructive pulmonary disease (COPD). Despite its medical relevance, relatively little is known about its mechanisms of pathogenicity. In this study, we found that NTHi invades the airway epithelium by a distinct mechanism, requiring microtubule assembly, lipid rafts integrity, and activation of phosphatidylinositol 3-kinase (PI3K) signalling. We found that the majority of intracellular bacteria are located inside an acidic subcellular compartment, in a metabolically active and non-proliferative state. This NTHi-containing vacuole (NTHi-CV) is endowed with late endosome features, co-localizing with LysoTracker, lamp-1, lamp-2, CD63 and Rab7. The NTHi-CV does not acquire Golgi- or autophagy-related markers. These observations were extended to immortalized and primary human airway epithelial cells. By using NTHi clinical isolates expressing different amounts of phosphocholine (PCho), a major modification of NTHi lipooligosaccharide, on their surfaces, and an isogenic lic1BC mutant strain lacking PCho, we showed that PCho is not responsible for NTHi intracellular location. In sum, this study indicates that NTHi can survive inside airway epithelial cells.


Assuntos
Células Epiteliais/microbiologia , Haemophilus influenzae/patogenicidade , Viabilidade Microbiana , Técnicas de Tipagem Bacteriana , Endocitose , Endossomos/química , Endossomos/microbiologia , Haemophilus influenzae/classificação , Haemophilus influenzae/metabolismo , Haemophilus influenzae/fisiologia , Humanos , Microdomínios da Membrana/metabolismo , Microtúbulos/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Transdução de Sinais , Virulência
9.
Foods ; 10(3)2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33652559

RESUMO

Aroma is an important quality parameter of fresh culinary herbs that may be highly affected after postharvest treatments. The innovative technology of vapor essential oil (EO) application under vacuum conditions may recover aroma lost during the postharvest processing of plant products like aromatic herbs. Hence, this study assessed the aroma recovery effect of vapor EOs applied during vacuum cooling on curly parsley and dill. The volatile organic compounds (VOCs) profiles of these aromatic herbs were studied by static headspace solid-phase microextraction (SPME), and the VOCs sorption kinetics onto the SPME stir-bar coating were modeled by the Baranyi model. At the pilot plant scale, the total VOCs contents of parsley and dill (whose extractability was increased by 10-20% after a single vacuum process) were enhanced by 4.5- and 2-fold, respectively, when vapor EOs were applied. In particular, 1,3,8-p-menthatriene and carvone (parsley) increased by 18.7- and 7.3-fold, respectively, while dill ether (the characteristic VOC of dill) augmented by 2.4-fold after vapor EOs were applied under vacuum conditions. The aroma recovery of culinary herbs was successfully validated at an industrial level in an installation developed by our group to apply vapor EOs within a vacuum cooling system, reaching total VOC recoveries of 4.9- and 2.3-fold in parsley and dill, respectively.

10.
Foods ; 10(4)2021 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-33916629

RESUMO

The antioxidant capacity of oregano (OEO) and clove (CLEO) essential oils and black elderberry (Sambucus nigra) flower extract (SNE) were compared with butylhydroxytoluene (BHT) regarding its protection against lipid peroxidation and microbial counts in salmon burgers stored at 4 °C for 14 days and after cooking. The content of total phenols was 5.74% in OEO, 2.64% in CLEO and 2.67 % in the SNE. The total phenolic content and the antioxidant capacity were significantly higher (p < 0.05) for SNE and OEO. Both essential oils showed a similar IC50 and inhibition percentage of lipid peroxidation to BHT. The combination of OEO and SNE reduced 29% of thiobarbituric acid reactive substances (TBARS), while BHT reduced 31% of TBARS generated during refrigeration storage in salmon burgers in relation to the control sample without antioxidants. Additionally, the microbial counts after 14 days of refrigeration were the lowest in burgers when the combination of OEO and SNE was used. This study concludes that OEO and SNE can be used as inhibitors of lipid oxidation in salmon products and as natural candidates to replace commonly used synthetic antioxidants and antimicrobials in these food products.

11.
Foods ; 10(6)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204542

RESUMO

Plant bioactive compounds have antimicrobial and antioxidant activities that allow them to be used as a substitute for synthetic chemical additives in both food and food packaging. To improve its sensory and bactericidal effects, its use in the form of effective combinations has emerged as an interesting possibility in the food industry. In this study, the antimicrobial activities of essential oils (EOs) of cinnamon bark, cinnamon leaves, and clove and the pure compounds vanillin, eugenol, and cinnamaldehyde were investigated individually and in combination against Listeria monocytogenes and Escherichia coli O157:H7. The possible interactions of combinations of pure compounds and EOs were performed by the two-dimensional checkerboard assay and isobologram methods. Vanillin exhibited the lowest antimicrobial activity (MIC of 3002 ppm against L. monocytogenes and 2795 ppm against E. coli O157:H7), while clove and cinnamon bark EOs exhibited the highest antimicrobial activity (402-404 against L. monocytogenes and 778-721 against E. coli O157:H7). For L. monocytogenes, pure compound eugenol, the main component of cinnamon leaves and clove, showed lower antimicrobial activity than EOs, which was attributed to the influence of the minor components of the EOs. The same was observed with cinnamaldehyde, the main component of cinnamon bark EO. The combinations of vanillin/clove EO and vanillin/cinnamon bark EO showed the most synergistic antimicrobial effect. The combination of the EOs of cinnamon bark/clove and cinnamon bark/cinnamon leaves showed additive effect against L. monocytogenes but indifferent effect against E. coli O157:H7. For L. monocytogenes, the best inhibitory effects were achieved by cinnamon bark EO (85 ppm)/vanillin (910 ppm) and clove EO (121 ppm)/vanillin (691 ppm) combinations. For E. coli, the inhibitory effects of clove EO (104 ppm)/vanillin (1006 ppm) and cinnamon leaves EO (118 ppm)/vanillin (979 ppm) combinations were noteworthy. Some of the tested combinations increased the antimicrobial effect and would allow the effective doses to be reduced, thereby offering possible new applications for food and active food packaging.

12.
Foods ; 10(6)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073204

RESUMO

The use of vapour of essential oils (EOs) through an innovative pilot-plant packaging device was studied to preserve the quality of sliced mushrooms during storage. A mix of EOs (eugenol, bergamot EO, and grapefruit EO) was vaporized (100 and 125 µL L-1) and applied during packaging of sliced mushrooms under modified atmosphere packaging (MAP); then, the product quality was studied during cold storage up to 12 days. The highest colour changes of EOs125 samples, which were observed in the mushroom stipe, were not observed with the EOs100 atmosphere. Thus, the high polyphenoloxidase activity observed in untreated samples after 5-7 days was highly controlled with the vapour EOs atmospheres. Furthermore, the visual appearance scores of EOs100 samples were still over the limit of usability, while untreated samples were already below this threshold after 5 days of storage. A strong bacteriostatic effect was achieved with vapour EOs, reducing the Pseudomonas spp. (the main microbial genus in cultivated mushrooms) growth by ≈1.7 log CFU g-1, regardless of the EOs dose, after 12 days. The activity of phenyl ammonia lyase was also reduced up to ≈0.4 enzymatic units with the EOs100 treatment. Conclusively, packaging of sliced mushrooms under an atmosphere enriched with 100 µL L-1 EOs vapour highly controlled the quality loss of sliced mushrooms owing to their enzymatic inhibition and high bacteriostatic effect.

13.
Foods ; 9(12)2020 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-33352681

RESUMO

Plant essential oils (EOs) have several bioactive properties, highlighting their high antimicrobial and antioxidant capacities. As such, the use of EOs in active packaging has received special attention in the last few years. Nevertheless, the inhibitory effect of EOs on quality-degrading enzymatic systems of plant products during postharvest life has not been deeply studied. The effects of an EO active paper sheet on ethylene biosynthesis and quality (and related quality-degrading enzymes) of flat peach (Prunus persica var. platycarpa) samples were studied during 5 days (continental terrestrial transport) or 26 days (long maritime transport) storage at 2 or 8 °C, both followed by commercialization simulations (4 days at 22 °C). EOs released from active packaging reduced ethylene production by 40-50%, and by up to 70% after commercialization periods. These results were correlated with lower 1-aminocyclopropanecarboxylic acid (ACC) content and ACC-oxidase activity. Physicochemical fruit quality (as indicated by soluble solids content, titratable acidity, color, and firmness) was also better preserved by EO active sheets due to enzymatic inhibition (polygalacturonase and polyphenoloxidase). Furthermore, phenolic compounds (mainly catechin and cyanidin-3 glucoside) and total antioxidant capacity were increased (by up to 30 and 70%, respectively) in EO-packaged samples after 8 °C storage and the subsequent commercialization period. Conclusively, EO active paper sheets controlled ethylene production in flat peaches, maintained fruit quality, and even increased health-promoting bioactive compounds.

14.
Front Nutr ; 7: 559978, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33344489

RESUMO

The quality loss of fruit and vegetables should be minimized to reduce food waste during retail. In that sense, sustainable and effective post-harvest techniques/technologies are needed, showing active packaging including encapsulated essential oils a high potential. In that sense, we studied the effect of different sized active packages (including ß-cyclodextrin-EOs inclusion complex) on the quality of grapes, nectarines, and lettuces (as models of berry fruit, stone fruit, and leafy vegetables) during storage at 2°C (90-95% relative humidity). The active industrial tray showed the best effect on grapes and lettuce quality, as it reduced rachis dehydration and product weight loss (reduced by ≈50% in grapes after 30 days), reduced berry shatter (reduced by ≈40% in grapes after 30 days), highly maintained the physicochemical quality (soluble solid content, titratable acidity and firmness), and also reduced microbial growth (0.5-1.4 lower log units than non-active industrial tray). For nectarines, the package with the biggest active surface (large tray, 200 × 300 × 90) also showed the best-quality retention compared to smaller packages, showing nectarines within active large tray better microbial quality (0.6-1 lower log units than non-active large tray) and firmness. As expected, flow packaging of nectarines (using active trays) better controlled the product weight loss. In conclusion, active cardboard packages with greater active surface better preserved quality of grapes, nectarines and lettuce, which sensory quality was accepted after more than 30, 25, and 14 days at 2°C, respectively, contrary to non-active samples (~1 week less).

15.
Foods ; 9(5)2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32384627

RESUMO

Mandarins are usually sold in bulk and refrigerated in open cardboard boxes with a relatively short shelf-life (12-15 days) due to physiological and pathological disorders (rot, dehydration, internal breakdown, etc.). The influence of a controlled release of essential oils (EOs) from an active packaging (including ß-cyclodextrin-EOs inclusion complex) was studied on the mandarin quality stability, comparing different sized cardboard trays and boxes, either non-active or active, at the pilot plant scale (experiment 1; commercialization simulation at room temperature after a previous simulation of short transportation/storage of 5 days at 8 °C). Then, the selected package was further validated at the industrial scale (experiment 2; cold storage at 8 °C up to 21 days). Among package types, the active large box (≈10 kg fruit per box) better maintained the mandarin quality, extending the shelf life from two weeks (non-active large box) to three weeks at room temperature. Particularly, the active large box highly controlled microbial growth (up to two log units), reduced weight losses (by 1.6-fold), reduced acidity, and increased soluble solids (highly appreciated in sensory analyses), while it minimized colour and controlled firmness changes after three weeks. Such trends were also observed during the validation experiment, extending the shelf life (based on sensory quality) from 14 to at least 21 days. In conclusion, the mandarin's shelf life with this active cardboard box format was extended more than one week at 8 °C.

16.
Foods ; 9(12)2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33256099

RESUMO

In the aquaculture industry, fish are stunned using a wide range of methods, but all of them trigger stress responses and affect the fish flesh quality. Chilled water is considered one of the most efficient methods, but even this is not a stress-free experience for the fish. Anesthetics included in the ice slurry or in water could decrease this stress and delay the loss of flesh quality. In this work, we analyze the effect of clove oil (CO) nanoencapsulated in ß-cyclodextrins (ß-CD) (CO + ß-CD), incorporated in the stunning bath, on the stress response and the organoleptic attributes of fresh marine and freshwater fish from four economically important fish species: Atlantic salmon, European seabass, Nile tilapia, and Rainbow trout. CO + ß-CD reduces the time required to induce anesthesia, independently of water salinity, habitat or water temperature. The plasmatic glucose and cortisol levels decreased in all four species, although the concentrations of CO varied between species. Moreover, plasmatic lactate level differed between the marine and freshwater fish. The use of CO + ß-CD extended the shelf life of fish from all the species studied (by 3-7 days). In conclusion, using CO encapsulated in ß-CD for anesthetizing fish can be regarded as an improved fish-stunning technique that reduces the anesthesia-induction time, decreases the stress response, and extends the shelf life of fresh fish.

17.
Heliyon ; 5(6): e01804, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31286075

RESUMO

Ice containing essential oils (EOs) nanoencapsulated in ß-cyclodextrins (ß-CD) (named as EOs+ß-CD ice) was used for stunning/slaughtering by hypothermia in ice slurry, and for ice storage of gilthead seabream. Clove essential oil (CEO) was used at fish stunning/slaughtering, while ice storage of whole fish was performed using a combination of carvacrol, bergamot and grapefruit EOs (CBG). Inclusion complexes CBG+ß-CD were characterized, and antimicrobial effect was also evaluated. The kneading method used to form inclusion complexes with CBG showed a good complexation efficiency. Microbial, physical-chemical and sensory analyses were carried out to assess the quality changes of fresh whole seabream during ice storage at 2 °C for 17 days. Results (microbial, chemical and sensorial) indicated that seabream stunning/slaughtering and storage using EOs+ß-CD ice (in low doses of 15 mg/kg ice for stunning, and 50 mg/kg ice for ice storage) improved the quality of fresh fish and extended the shelf-life up to 4 days.

18.
Cell Death Dis ; 9(12): 1156, 2018 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-30464201

RESUMO

Common variable immunodeficiency (CVID) is characterized by an abnormal B cell differentiation to memory and antibody-secreting B cells. The defective functionality of CVID patients' B cells could be the consequence of alterations in apoptosis regulation. We studied the balance of Bcl-2 family anti-/pro-apoptotic proteins to identify molecular mechanisms that could underlie B cell survival defects in CVID. We used flow cytometry to investigate Bcl-2, Bcl-XL, Bax, and Bim expression in B cells ex vivo and after anti-CD40 or anti-BCR activation with or without IL-21, besides to spontaneous and stimulation-induced Caspase-3 activation and viable/apoptotic B cell subpopulations. We found increased basal levels of Bax and Bim in CVID B cells that correlated with low viability and high Caspase-3 activation only in CD27+ B cells, particularly in a subgroup of apoptosis-prone CVID (AP-CVID) patients with low peripheral B cell counts and high autoimmunity prevalence (mostly cytopenias). We detected a broad B cell defect in CVID regarding Bcl-2 and Bcl-XL induction, irrespective of the stimulus used. Therefore, peripheral CVID memory B cells are prompted to die from apoptosis due to a constitutive Bcl-2 family protein imbalance and defective protection from activation-induced apoptosis. Interestingly, anti-CD40 and IL-21 induced normal and even higher levels of Bcl-XL, respectively, in CD27+ B cells from AP-CVID, which was accompanied by cell viability increase. Thus low-survival memory B cells from AP-CVID can overcome their cell death regulation defects through pro-survival signals provided by T cells. In conclusion, we identify apoptosis regulation defects as disease-contributing factors in CVID. B cell counts and case history of cytopenias might be useful to predict positive responses to therapeutic approaches targeting T-dependent signaling pathways.


Assuntos
Linfócitos B/metabolismo , Imunodeficiência de Variável Comum/genética , Interleucinas/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Receptores de Antígenos de Linfócitos B/genética , Adulto , Apoptose/imunologia , Linfócitos B/imunologia , Linfócitos B/patologia , Proteína 11 Semelhante a Bcl-2/genética , Antígenos CD40/genética , Imunodeficiência de Variável Comum/imunologia , Imunodeficiência de Variável Comum/patologia , Feminino , Regulação da Expressão Gênica/genética , Humanos , Memória Imunológica , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia , Linfócitos T/metabolismo , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/genética , Proteína X Associada a bcl-2/genética , Proteína bcl-X/genética
19.
J Infect Dev Ctries ; 12(2): 89-96, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-31825909

RESUMO

INTRODUCTION: Noma is an opportunistic polymicrobial infection that cause necrosis of the mouth and face, with high morbidity and mortality, predominantly affecting malnourished children and persons with debilitating diseases. Cases of noma-like disease in adults, although rare, have been increasingly reported in HIV/AIDS patients particularly in developing countries but also in more developed countries. METHODOLOGY: A systematic review of the literature to assess the occurrence and clinical impact of noma and noma-like disease in HIV/AIDS patients was performed on PubMed, Virtual Health Library, Cochrane Library and Google Scholar using the keywords "HIV"[ All Fields] AND "Noma"[All Fields] in December 2016 (years includead for the search: 1985 to 2016). RESULTS: Twenty-four published studies were identified that document the occurrence of noma or noma-like disease in a total of 133 HIV/AIDS children and adult patients in the last 22 years. Although HIV infection is not the principal risk factor for noma, in some regions may play a substantial role in its pathogenesis. The mortality rate for noma-like disease in HIV/AIDS patients was 54.3%, compared to the 15% mortality rate of treated noma patients without HIV/AIDS. Most of the cases have never been on antiretroviral therapy, and their HIV infection was discovered because of the noma-like disease. CONCLUSIONS: The syndemic interaction between HIV/AIDS and noma-like disease adversely impacts the severity of the disease and the mortality rate. Noma-like disease, although not yet considered a specific or frequent disease associated with HIV infection, should be considered as an opportunistic infection for AIDS.

20.
Front Immunol ; 9: 1097, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29896193

RESUMO

Multiple sclerosis (MS) is considered a T cell-mediated autoimmune disease, although several evidences also demonstrate a B cell involvement in its etiology. Follicular T helper (Tfh) cells, a CXCR5-expressing CD4+ T cell subpopulation, are essential in the regulation of B cell differentiation and maintenance of humoral immunity. Alterations in circulating (c)Tfh distribution and/or function have been associated with autoimmune diseases including MS. Dimethyl fumarate (DMF) is a recently approved first-line treatment for relapsing-remitting MS (RRMS) patients whose mechanism of action is not completely understood. The aim of our study was to compare cTfh subpopulations between RRMS patients and healthy subjects and evaluate the impact of DMF treatment on these subpopulations, relating them to changes in B cells and humoral response. We analyzed, by flow cytometry, the distribution of cTfh1 (CXCR3+CCR6-), cTfh2 (CXCR3-CCR6-), cTfh17 (CXCR3-CCR6+), and the recently described cTfh17.1 (CXCR3+CCR6+) subpopulations of CD4+ Tfh (CD45RA-CXCR5+) cells in a cohort of 29 untreated RRMS compared to healthy subjects. CD4+ non-follicular T helper (Th) cells (CD45RA-CXCR5-) were also studied. We also evaluated the effect of DMF treatment on these subpopulations after 6 and 12 months treatment. Untreated RRMS patients presented higher percentages of cTfh17.1 cells and lower percentages of cTfh2 cells consistent with a pro-inflammatory bias compared to healthy subjects. DMF treatment induced a progressive increase in cTfh2 cells, accompanied by a decrease in cTfh1 and the pathogenic cTfh17.1 cells. A similar decrease of non-follicular Th1 and Th17.1 cells in addition to an increase in the anti-inflammatory Th2 subpopulation were also detected upon DMF treatment, accompanied by an increase in naïve B cells and a decrease in switched memory B cells and serum levels of IgA, IgG2, and IgG3. Interestingly, this effect was not observed in three patients in whom DMF had to be discontinued due to an absence of clinical response. Our results demonstrate a possibly pathogenic cTfh pro-inflammatory profile in RRMS patients, defined by high cTfh17.1 and low cTfh2 subpopulations that is reverted by DMF treatment. Monitoring cTfh subsets during treatment may become a biological marker of DMF effectiveness.


Assuntos
Fumarato de Dimetilo/uso terapêutico , Imunossupressores/uso terapêutico , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/imunologia , Linfócitos T/imunologia , Adulto , Idoso , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Linfócitos B/metabolismo , Biomarcadores , Fumarato de Dimetilo/farmacologia , Feminino , Humanos , Imunoglobulinas/sangue , Imunoglobulinas/imunologia , Imunofenotipagem , Imunossupressores/farmacologia , Estudos Longitudinais , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/metabolismo , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Resultado do Tratamento
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