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1.
World J Microbiol Biotechnol ; 40(1): 18, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37985512

RESUMO

Three types of silver/silver chloride nanoparticles were obtained by green synthesis from three types of microbial biomass. Their biocidal capacity was tested against six microorganisms. Two filamentous fungi were used that had previously demonstrated the ability to synthesise nanoparticles, Penicillium sp. 8L2 and Botryosphaeria rhodina MAMB-05. Also, the synthesis capacity of a yeast, Rhodotorula mucilaginosa 1S1, was evaluated. The original protocols underwent slight modifications. At the same time, the fractional inhibitory concentration was obtained. The interaction between specific antibiotics and the nanoparticles that showed the greatest biocidal capacity came from Penicillium sp.8L2, and it was studied further. All nanoparticles were characterised by UV-vis spectrophotometry and transmission electron microscopy (TEM). Also, their size distribution was analysed, which was in the range of 4 to 34 nm. The biocidal capacity of the nanoparticles for a group of bacteria and fungi was studied, presenting very low values in the range of 2.5-10 µg/mL for bacteria and 4-256 µg/mL for fungi. The interactions between the nanoparticles synthesised by Penicillium sp. 8L2 and a group of specific antibiotics for the tested microorganisms were also studied, proving that there was a synergistic interaction with vancomycin and ciprofloxacin and Staphylococcus epidermidis CECT 4183 and Escherichia coli CECT 101 bacteria, respectively.


Assuntos
Nanopartículas Metálicas , Prata , Prata/farmacologia , Cloretos , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Bactérias
2.
Clin Transl Oncol ; 25(12): 3492-3500, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37247131

RESUMO

INTRODUCTION: This study investigated the impact of systemic cancer therapy on the quality of life, mental well-being, and life satisfaction of cancer patients. METHODS: This prospective study was promoted by the Spanish Society of Medical Oncology (SEOM) and enrolled patients with localized, resected, or unresectable advanced cancer from 15 Spanish medical oncology departments. Patients completed surveys on quality of life (EORTC-QoL-QLQ-C30), psychological distress (BSI-18) and life satisfaction (SWLS) before and after systemic cancer treatment. RESULTS: The study involved 1807 patients, 944 (52%) having resected, localized cancer, and 863 with unresectable advanced cancer. The mean age was 60 years, and 53% were female. The most common types of localized cancer were colorectal (43%) and breast (38%), while bronchopulmonary (32%), non-colorectal digestive (23%), and colorectal (15%) were the most frequent among those with advanced cancer. Before systemic treatment, patients with advanced cancer had poorer scores than those with localized cancer on physical, role, emotional, cognitive, social limitations, symptoms, psychological distress, and life satisfaction (all p < 0.001), but there were no differences in financial hardship. Patients with localized cancer had greater life satisfaction and better mental well-being than those with advanced cancer before systemic treatment (p < 0.001). After treatment, patients with localized cancer experienced worsening of all scales, symptoms, and mental well-being (p < 0.001), while patients with advanced disease had a minor decline in quality of life. The impact on quality of life was greater on all dimensions except economic hardship and was independent of age, cancer location, and performance status in participants with resected disease after adjuvant chemotherapy. CONCLUSION: In conclusion, our study highlights that systemic cancer treatment can improve quality of life in patients with advanced cancer, while adjuvant treatments for localized disease may have a negative impact on quality of life and psychological well-being. Therefore, treatment decisions should be carefully evaluated on an individual basis.


Assuntos
Neoplasias Colorretais , Qualidade de Vida , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Qualidade de Vida/psicologia , Estudos Prospectivos , Emoções , Bem-Estar Psicológico , Inquéritos e Questionários , Neoplasias Colorretais/terapia
3.
Nanomaterials (Basel) ; 13(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36678048

RESUMO

The efficiency of Rhodotorula mucilaginosa 1S1 as an Ag(I) biosorbent and at the same time its ability to biosynthesize recoverable silver nanoparticles is evaluated. Kinetic, equilibrium and thermodynamic tests are carried out for 19 °C, 27 °C and 37 °C, from which the process is adjusted to a pseudo second-order kinetics and to the Freundlich model, while optimal operational conditions are determined at 27 °C. The thermodynamic study shows positive values for enthalpy (ΔH: 133.23 kJ/mol) and entropy (ΔS: 0.4976 kJ/(mol K)), while the Gibbs free energy (ΔG) value is 12.136 kJ/mol. For a metal concentration of 459 mg/L, a maximum biosorption capacity (qm) of 137.2 mg/g at 19 °C is obtained, while for 100 mg/L concentration a qm value of 60.44 mg/g is obtained at the same temperature. The mechanisms involved in the biosorption process are studied by infrared spectroscopy, X-ray diffraction and scanning and transmission electron microscopy, while the nanoparticle synthesis is evaluated by ultraviolet-visible spectrophotometry (UV-vis) and transmission electron microscopy. The results indicate that the biomass is a good biosorbent and also has the ability to synthesize silver nanoparticles (Ag/AgCl) with sizes between 12 nm and 20 nm.

4.
iScience ; 25(10): 105078, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36157587

RESUMO

CD6 is a lymphocyte-specific scavenger receptor expressed on adaptive (T) and innate (B1a, NK) immune cells, which is involved in both fine-tuning of lymphocyte activation/differentiation and recognition of bacterial-associated molecular patterns (i.e., lipopolysaccharide). However, evidence on CD6's role in the physiological response to bacterial infection was missing. Our results show that induction of monobacterial and polymicrobial sepsis in Cd6 -/- mice results in lower survival rates and increased bacterial loads and pro-inflammatory cytokine levels. Steady state analyses of Cd6 -/- mice show decreased levels of natural polyreactive antibodies, concomitant with decreased cell counts of spleen B1a and marginal zone B cells. Adoptive transfer of wild-type B cells and mouse serum, as well as a polyreactive monoclonal antibody improve Cd6 -/- mouse survival rates post-sepsis. These findings support a nonredundant role for CD6 in the early response against bacterial infection, through homeostatic expansion and functionality of innate-related immune cells.

5.
Front Psychol ; 13: 855704, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35693507

RESUMO

Objective: Loss of dignity is one of the main reasons for wishing for an early death in patients with incurable diseases such as cancer and is strongly associated with psychological distress and loss of quality of life. The present study aims to analyze the perceived dignity of patients with advanced cancer undergoing systemic treatment and their relationship with sociodemographic, clinical, and psychological factors. Methods: A prospective, cross-sectional, multicenter study was conducted in 15 oncology departments in Spain. Patients with locally advanced, unresectable, or metastatic cancer who were candidates for systemic treatment were included. Participants completed demographic information and Palliative Patients' Dignity Scale, Brief Symptom Inventory, Mental Adjustment to Cancer, Functional Social Support Questionnaire, and Illness Uncertainty. Results: A total of 508 patients were recruited between February 2020 and October 2021. Most were male, aged > 65 years, with digestive tumors (41%), and metastatic disease at diagnosis. Subjects were classified as having low (56%, N = 283) or high (44%, N = 225) perceived dignity. Patients ≥ 65 years, with worse baseline status (ECOG ≥ 1), and worse estimated 18-month survival had lower levels of perceived dignity. People with lower perceived dignity scored higher for anxious preoccupation and hopelessness and lower for positive attitude. They also displayed higher levels of anxiety, depression, and somatic symptoms, greater uncertainty, and less social support. Conclusion: Self-perceived dignity in advancer cancer patients is significantly associated with psychological factors, psychological distress, uncertainty, less social support. Knowledge of these specific interactions is importance for adequate, comprehensive palliative care.

6.
Cancer Invest ; 40(6): 475-482, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35468046

RESUMO

This study examines the mediating role of social support between anxious preoccupation and resilience in patients with cancer during COVID-19. NEOetic_SEOM is a prospective, multicenter study involving individuals with advanced, unresectable cancer who completed the following scales: Resilience (BCRS), Social Support (Duke-UNC-11), and anxious preoccupation subscale of the Mini-Mental Adjustment to Cancer (M-MAC) before starting antineoplastic treatment. Between March 2020 and July 2021, 507 patients (55% male; mean age, 65) were recruited. No differences in resilience were observed based on sociodemographic or clinical characteristics. Social support in people with advanced, unresectable cancer promotes both decreased anxious preoccupation and greater resilience.


Assuntos
COVID-19 , Neoplasias , Adaptação Psicológica , Idoso , Feminino , Humanos , Masculino , Pandemias , Estudos Prospectivos , Apoio Social
7.
Antioxidants (Basel) ; 11(2)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35204087

RESUMO

Refined olive oils (ROOs) are commonly enriched with synthetic antioxidants. Antioxidant extracts obtained from natural products can be used to improve the stability of these oils. In this study, ROOs were enriched through the addition of phenolic extracts from olive leaves (OLs) and exhausted olive pomace (EOP). In addition to replacing synthetic antioxidants with natural ones, this results in the valorization of these olive-derived biomasses. The most suitable method for mixing and enriching refined oils was probe-type ultrasonication using lecithin as the emulsifier. Thereafter, the change in the content of antioxidant compounds and the antioxidant capacity of the oils at 25, 35, and 45 °C were studied over 28 and 50 days of storage. The experimental results were fitted using a pseudo-first-order kinetic model. The oxidative stability index of the ROO enriched with a 2 g/L OL extract (70 h) was higher than that of a commercial ROO (46.8 h). Moreover, the oxidative stability index of the refined olive pomace oil (ROPO) enriched with a 2 g/L EOP extract (44.1 h) was higher than that of a commercial ROPO (38.9 h). In addition, the oxidative stabilities and antioxidant capacities of the oils were significantly correlated.

8.
Support Care Cancer ; 30(4): 3363-3370, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34993652

RESUMO

OBJECTIVE: Cancer patients are at increased risk for psychological difficulties and COVID-19. We sought to analyze anxiety and depression levels during the COVID-19 pandemic and the association between sociodemographic, clinical, and psychological factors in patients with advanced cancer. METHODS: A prospective, multicenter cohort of 401 consecutive patients with newly diagnosed, advanced cancer completed the Brief Symptom Inventory, Michel Uncertainty in Illness Scale, Herth Hope Index, and Cancer Worry Scale between February 2020 and May 2021. Linear regression analyses explored the effects of uncertainty, hopelessness, and cancer worry on anxiety and depression, adjusting for sociodemographic and clinical variables. RESULTS: The incidence of anxiety and depression was 36% and 35%, respectively. Emotional distress was greater among women, patients < 65 years of age, and those with an estimated survival of > 18 months. Linear regression analysis revealed that being female, preoccupation about cancer, and hopelessness were associated with increased levels of anxiety (p < 0.001) and depression (p < 0.001) and younger age was associated with a higher risk of anxiety. No differences in anxiety or depression levels were found in relation to marital status, children, educational level, cancer type, histology, stage, or type of treatment. CONCLUSIONS: Patients with advanced cancer who initiated treatment during the pandemic experienced high levels of depression and anxiety. Early diagnosis and the development of intervention strategies are necessary, especially for specific patient subgroups, such as young women with long survival times.


Assuntos
COVID-19 , Neoplasias , Ansiedade/epidemiologia , Ansiedade/etiologia , Ansiedade/psicologia , Criança , Depressão/diagnóstico , Depressão/epidemiologia , Depressão/etiologia , Detecção Precoce de Câncer , Feminino , Humanos , Neoplasias/epidemiologia , Pandemias , Estudos Prospectivos , SARS-CoV-2 , Estresse Psicológico/etiologia
9.
BMC Pediatr ; 21(1): 446, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34629070

RESUMO

BACKGROUND: The fat mass estimators waist-to-height ratio (WHtR) and relative fat mass-pediatric (RFMp) complement the widely accepted body mass index (BMI) in obesity evaluation. AIMS OF THE STUDY: Conduct an easy appraisal of trunk fat and the cardiometabolic risk associated with pediatric obesity. METHODS: A total of 472 children (39% boys in the total sample) were classified as underweight, normal weight, overweight or obese (nutritional groups, NGs) according to BMI Z-score after initial anthropometric data were obtained and ad hoc exclusion criteria were applied. WHtR and RFMp (% of total fat) were calculated for each group, associations were assessed through multiple linear regression (MLR), and differences between sexes were evaluated (medians, IQR). RESULTS: The mean age (mean (95% CI)) was 10.8 y (10.1-11.1). The values in the total sample were as follows: WHtR, 0.5 (0.49-0.51) and RFMp%, 32.3 (31.7-33.0). In the overweight group, the values were as follows: WHtR, 0.51 (0.50-0.52) and RFMp(%), 34.2 (33.3-35.1). In the obese group, the values were as follows: WHtR, 0.56 (0.55-0.57) and RFMp(%), 37.8 (36.9-38.6). The associations were as follows (NG; independent variables): In the NG, adjusted R2 values were between 0.74 and 0.78. In the total sample, the beta coefficient was 3.36 (P < 0.001) for RFMp for girls; for waist circumference (WC), the beta coefficient was 2.97 (P < 0.001), and for WHtR the beta coefficients were - 0.01 (p < 0.001) and 0.03 (p < 0.001),for girls and for WC respectively. The sex differences were as follows: BMI exhibited no differences in the NG (Mann-Whitney U). WHtR (median (IQR)) differed (M vs. F) in the total sample (0.49 (0.45-0.54) vs. 0.52 (0.45-0.56), p < 0.004); in the overweight group (0.51 (0.48-0.53) vs. 0.54 (0.51-0.55), p < 0.001); and in the obese group (0.55 (0.52-0.57) vs. 0.57 (0.54-0.60), p < 0.004). RFMp (%) differed in the total group (29.21 (24.27-32.92) vs. 36.63 (30.2-39.51), p < 0.001); in the overweight group (31.24 (28.35-32.35) vs. 37.95 (35.75-38.82), p < 0.001) and in the obese group (35.89 (32.05-36.15) vs. 40.63 (38.27-42.42), p < 0.001). CONCLUSIONS: WHtR and RFMp are simple and reliable indices that do not require centile charts. Their values, including waist circumference, can be used to estimate the different trunk fat components in boys and girls better than BMI, especially if individuals are overweight or obese. RFMp proved to be more reliable as it considers sex. Both should be included in routine anthropometric readings.


Assuntos
Obesidade Infantil , Razão Cintura-Estatura , Índice de Massa Corporal , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Obesidade Infantil/diagnóstico , Circunferência da Cintura
10.
Front Immunol ; 12: 666545, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968069

RESUMO

In genetically prone individuals, chronic immune activation may lead to expansion of autoreactive lymphocyte clones that can induce organ damage developing autoimmune disorders. Sjögren's Syndrome (SjS) is a systemic chronic autoimmune disease that primarily affects exocrine glands. Despite the accumulated evidences of profound B-cell alterations of humoral immunity, the repertoire and development of B-cell autoreactivity in SjS remains to be determined. We hypothesize that SjS mice will have an increased frequency of self-reactive B cells with a progressive evolution to antigen-driven oligoclonality. Here, we study the B cell repertoire of NOD.H-2h4 mice, a mouse model of spontaneous autoimmunity mimicking SjS without developing diabetes. A library of 168 hybridomas from NOD.H-2h4 mice and 186 C57BL/6J splenocytes at different ages was created. The presence of mono or polyreactive autoantibodies to several antigens was evaluated by ELISA, and their staining patterns and cellular reactivity were tested by IFA and FACS. We observed a higher frequency of autoreactivity among B-cell clones from NOD.H-2h4 mice as compared to wild-type mice. The presence of polyreactive and autoreactive IgG clones increased with mice age. Strikingly, all anti-Ro52 autoantibodies were polyreactive. No loss of polyreactivity was observed upon antibody class switching to IgG. There was a progression to oligoclonality in IgG B cells with mice aging. Our results indicate that in the NOD.H-2h4 mouse model of SjS, IgG+ B cells are mainly polyreactive and might expand following an unknown antigen-driven positive selection process.


Assuntos
Autoimunidade , Linfócitos B/metabolismo , Glândulas Salivares/patologia , Síndrome de Sjogren/imunologia , Animais , Autoanticorpos/imunologia , Autoantígenos/imunologia , Modelos Animais de Doenças , Feminino , Imunoglobulina G/imunologia , Imunoglobulina G/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD
11.
Molecules ; 26(5)2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33671061

RESUMO

Wild olive trees have important potential, but, to date, the oil from wild olives has not been studied significantly, especially from an analytical point of view. In Spain, the wild olive tree is called "Acebuche" and its fruit "Acebuchina". The objective of this work is to optimize the olive oil production process from the Acebuchina cultivar and characterize the oil, which could be marketed as healthy and functional food. A Box-Behnken experimental design with five central points was used, along with the Response Surface Methodology to obtain a mathematical experimental model. The oils from the Acebuchina cultivar meet the requirements for human consumption and have a good balance of fatty acids. In addition, the oils are rich in antioxidants and volatile compounds. The highest extraction yield, 12.0 g oil/100 g paste, was obtained at 90.0 min and the highest yield of phenolic compounds, 870.0 mg/kg, was achieved at 40.0 °C, and 90.0 min; but the maximum content of volatile compounds, 26.9 mg/kg, was obtained at 20 °C and 30.0 min. The oil yield is lower than that of commercial cultivars, but the contents of volatile and phenolic compounds is higher.


Assuntos
Antioxidantes/química , Olea/química , Azeite de Oliva/química , Extratos Vegetais/química , Antioxidantes/farmacologia , Ácidos Graxos/química , Humanos , Azeite de Oliva/farmacologia , Fenóis/química , Extratos Vegetais/farmacologia , Espanha , Compostos Orgânicos Voláteis/química
12.
Food Chem ; 329: 127153, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32512392

RESUMO

Olive leaves are an under valorized residue of olive tree pruning and olive fruit harvesting and that are usually removed by either burning or grinding and scattering them on fields. However, as plant material easily available, they may be used as raw material in biorefineries, or for the industrial manufacture of many diverse products, given their lignocellulosic composition. Like other lignocellulosic biomasses, the composition of olive leaves depends on cultivar and to know it is essential for an adequate use. Therefore, this work tackles a characterization analysis of the lignocellulosic fraction of some olive leaf cultivars, both commercial and wild. In general, the cultivars studied did not show large differences in their quantitative composition, except for the content of ethanolic extractives and cellulose of the commercial and wild cultivars. In addition, the high lignin content (around 15%) is remarkable.


Assuntos
Lignina/química , Olea/química , Açúcares/química , Biomassa , Extratos Vegetais/química , Folhas de Planta/química
13.
Food Chem ; 320: 126626, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32222659

RESUMO

Olive leaves are considered a promising source of bioactives such as phenolic compounds and mannitol. The extraction of high added value products is an issue of great interest and importance from the point of view of their exploitation. However, the content of these compounds can differ between cultivars and extraction methods. In this work, six olive leaves cultivars, including three wild cultivars, and two extraction processes (an innovative and alternative technique, pressurized liquid extraction, and a conventional Soxhlet extraction) were evaluated and compared towards the selective recovery of bioactive compounds. The wild cultivars showed the highest content of phenolic and flavonoid compounds, being oleuropein the compound present in higher amount. Findings also revealed that the highest mannitol content in the extracts was observed with the commercial cultivars, specifically in Arbequina. It is thus possible to decide which cultivars to use in order to obtain the highest yield of each bioproduct.


Assuntos
Manitol/análise , Olea/química , Fenóis/análise , Extratos Vegetais/química , Flavonoides/análise , Glucosídeos Iridoides , Iridoides/análise , Folhas de Planta/química , Pressão , Espanha
14.
Food Chem ; 314: 126218, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31982857

RESUMO

Olive leaves farmed from trees are valuable for the production of functional extracts. Nonetheless, olive leaves (containing thin branches), which are separated during olives cleaning in the mill, have received little attention. In this context, a multiple response optimization was performed to maximize at once the yield, total phenolic content, oleouropein and antioxidant activity obtained by ultrasound-assisted extraction of this low-cost byproduct. The optimum was achieved using the following operational parameters: solid-to-liquid ratio, 5.9%; ethanol concentration, 47%; extraction time, 50 min. This enabled to obtain an extract with both high level of oleuropein and antioxidant activity. Besides oleuropein, other minor phenolic compounds were characterized in the extract, which could contribute to the antioxidant activity as Pearson correlation suggested. After this extraction step, how the phenolic extraction affects the recovery/profile of other constituents was evaluated, looking for the integral valorization of this resource towards the zero-waste.


Assuntos
Fracionamento Químico/métodos , Iridoides/isolamento & purificação , Olea/química , Folhas de Planta/química , Etanol , Glucosídeos Iridoides , Fenóis , Ondas Ultrassônicas
15.
Foods ; 8(11)2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31671747

RESUMO

The extraction of bioactive compounds in a biorefinery context could be a way to valorize agri-food byproducts, but there is a remaining part that also requires attention. Therefore, in this work the integrated extraction of phenolic compounds, including the bioactive oleuropein, and proteins from olive mill leaves was addressed following three schemes, including the use of ultrasound. This affected the total phenolic content (4475.5-6166.9 mg gallic acid equivalents/100 g), oleuropein content (675.3-1790.0 mg/100 g), and antioxidant activity (18,234.3-25,459.0 µmol trolox equivalents/100 g). No effect was observed on either the protein recovery or the content of sugars and lignin in the extraction residues. Concerning the recovery of proteins, three operational parameters were evaluated by response surface methodology. The optimum (63.1%) was achieved using NaOH 0.7 M at 100 °C for 240 min. Then, the selected scheme was applied to olive leaves from the field, observing differences in the content of some of the studied components. It also changed the lignocellulosic profile of the extraction residues of both leaf types, which were enriched in cellulose. Overall, these results could be useful to diversify the valorization chain in the olive sector.

16.
Molecules ; 24(19)2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31590381

RESUMO

Three factors for the extraction of extra virgin olive oil (EVOO) were evaluated: diameter of the grid holes of the hammer-crusher, malaxation temperature, and malaxation time. A Box-Behnken design was used to obtain a total of 289 olive oil samples. Twelve responses were analyzed and 204 mathematical models were obtained. Olives from super-intensive rainfed or irrigated crops of the Arbequina, Koroneiki, and Arbosana cultivars at different stages of ripening were used. Malaxation temperature was found to be the factor with the most influence on the total content of lipoxygenase pathway volatile compounds; as the temperature increased, the content of volatile compounds decreased. On the contrary, pigments increased when the malaxation temperature was increased. EVOO from irrigated crops and from the Arbequina cultivar had the highest content of volatile compounds. Olive samples with a lower ripening degree, from the Koroneiki cultivar and from rainfed crops, had the highest content of pigments.


Assuntos
Olea/crescimento & desenvolvimento , Azeite de Oliva/análise , Compostos Orgânicos Voláteis/análise , Irrigação Agrícola/métodos , Manipulação de Alimentos , Lipoxigenase/metabolismo , Modelos Teóricos , Odorantes/análise , Olea/química , Olea/classificação , Olea/metabolismo , Azeite de Oliva/classificação , Fenóis/análise , Proteínas de Plantas/metabolismo , Temperatura
17.
Redox Biol ; 26: 101258, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31234016

RESUMO

Using non-reducing Western blotting to assess protein thiol redox state is challenging because most reduced and oxidised forms migrate at the same molecular weight and are, therefore, indistinguishable. While copper catalysed Click chemistry can be used to ligate a polyethylene glycol (PEG) moiety termed Click PEGylation to mass shift the reduced or oxidised form as desired, the potential for copper catalysed auto-oxidation is problematic. Here we define a catalyst-free trans-cyclooctene-methyltetrazine (TCO-Tz) inverse electron demand Diels Alder chemistry approach that affords rapid (k ~2000 M-1 s-1), selective and bio-orthogonal Click PEGylation. We used TCO-Tz Click PEGylation to investigate how fertilisation impacts reversible mitochondrial ATP synthase F1-Fo sub-unit alpha (ATP-α-F1) oxidation-an established molecular correlate of impaired enzyme activity-in Xenopus laevis. TCO-Tz Click PEGylation studies reveal substantial (~65%) reversible ATP-α-F1 oxidation at evolutionary conserved cysteine residues (i.e., C244 and C294) before and after fertilisation. A single thiol is, however, preferentially oxidised likely due to greater solvent exposure during the catalytic cycle. Selective reduction experiments show that: S-glutathionylation accounts for ~50-60% of the reversible oxidation observed, making it the dominant oxidative modification type. Intermolecular disulphide bonds may also contribute due to their relative stability. Substantial reversible ATP-α-F1 oxidation before and after fertilisation is biologically meaningful because it implies low mitochondrial F1-Fo ATP synthase activity. Catalyst-free TCO-Tz Click PEGylation is a valuable new tool to interrogate protein thiol redox state in health and disease.


Assuntos
Química Click/métodos , Mitocôndrias/química , ATPases Mitocondriais Próton-Translocadoras/química , Óvulo/química , Polietilenoglicóis/química , Processamento de Proteína Pós-Traducional , Subunidades Proteicas/química , Trifosfato de Adenosina/biossíntese , Sequência de Aminoácidos , Animais , Dissulfetos/química , Embrião não Mamífero , Feminino , Fertilização in vitro , Glutationa/metabolismo , Compostos Heterocíclicos com 1 Anel/química , Masculino , Mitocôndrias/enzimologia , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Óvulo/citologia , Óvulo/enzimologia , Oxirredução , Filogenia , Subunidades Proteicas/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Compostos de Sulfidrila/química , Compostos de Sulfidrila/metabolismo , Xenopus laevis/classificação , Xenopus laevis/embriologia , Xenopus laevis/metabolismo
18.
Food Chem ; 293: 161-168, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151597

RESUMO

Olive leaves have become a promising source of phenolic compounds and flavonoids with high added value. Phenolic compounds and flavonoids are important sources of antioxidants and bioactives, and one of the processes used to effectively produce them is extraction via solvents, using aqueous ethanol solutions. To obtain the highest extraction yield per kg of biomass, olive leaves were extracted using a conventional technique (dynamic maceration) and an emerging technology, such as pressurized liquid extraction. Studies of the factors that influence these processes were performed: temperature, leaf moisture content, solvent/solid, and aqueous ethanol concentration were optimized using the central composite and Box-Behnken experiment designs. Pressurized liquid extraction resulted in more efficient oleuropein and luteolin-7-O-glucoside extraction than dynamic maceration. The operational conditions for maximizing the recovery of phenolic compounds and flavonoids and antioxidant capacity were determined to be 190 °C, leaf moisture content of 5%, and aqueous ethanol concentration of 80%.


Assuntos
Flavonas/química , Glucosídeos/química , Iridoides/química , Olea/química , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Flavonas/isolamento & purificação , Flavonoides , Glucosídeos/isolamento & purificação , Glucosídeos Iridoides , Iridoides/isolamento & purificação , Olea/metabolismo , Fenóis/química , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Solventes/química , Temperatura
19.
Bioresour Technol ; 280: 459-477, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30777702

RESUMO

The biorefinery concept is attracting scientific and policy attention as a promising option for enhancing the benefits of agri-food biomass along with a reduction of the environmental impact. Obtaining bioproducts based on proteins from agri-food residues could help to diversify the revenue stream in a biorefinery. In fact, the extracted proteins can be applied as such or in the form of hydrolyzates due to their nutritional, bioactive and techno-functional properties. In this context, the present review summarizes, exemplifies and discusses conventional extraction methods and current trends to extract proteins from residues of the harvesting, post-harvesting and/or processing of important crops worldwide. Moreover, those extraction methods just integrated in a biorefinery scheme are also described. In conclusion, a plethora of methods exits but only some of them have been applied in biorefinery designs, mostly at laboratory scale. Their economic and technical feasibility at large scale requires further study.


Assuntos
Produtos Agrícolas , Proteínas de Plantas/isolamento & purificação , Animais , Biomassa , Humanos
20.
Front Immunol ; 9: 2661, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30519241

RESUMO

Sjögren's Syndrome (SjS) is a common chronic autoimmune disease characterized by the B cell hyperactivation, lymphocyte infiltration, and tissue damage of exocrine glands. It can also present life-threatening extraglandular manifestations, such as pulmonary and hepatic involvement, renal inflammation and marginal zone (MZ) B cell lymphoma. Several biologic agents have been tested in SjS but none has shown significant efficacy. Here, we report the effects of Ly9 (CD229) antibody targeting, a cell surface molecule that belongs to the SLAM family of immunomodulatory receptors, using NOD.H-2h4 mice as a model of SjS-like disease. Female mice were treated with anti-Ly9 antibody or isotype control at week 24, when all mice present SjS related autoantibodies, salivary gland infiltrates, and marginal zone (MZ) B cell pool enlargement. Antibody injection depleted key lymphocyte subsets involved in SjS pathology such as MZ, B1, and germinal center B cells in spleen and draining lymph nodes without inducing a general immunosuppression. Importantly, mice receiving anti-Ly9 mAb showed a reduced lymphocyte infiltrate within salivary glands. This reduction may be, in part, explained by the down-regulation of L-selectin and alfa4/beta7 integrin induced by the anti-Ly9 antibody. Furthermore, levels of anti-nuclear autoantibodies were reduced after anti-Ly9 treatment. These data indicate that Ly9 is a potential therapeutic target for the treatment of SjS.


Assuntos
Linfócitos B/metabolismo , Centro Germinativo/patologia , Tecido Linfoide/imunologia , Glândulas Salivares/patologia , Sialadenite/imunologia , Família de Moléculas de Sinalização da Ativação Linfocitária/imunologia , Síndrome de Sjogren/imunologia , Animais , Autoanticorpos/imunologia , Autoanticorpos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Movimento Celular/imunologia , Modelos Animais de Doenças , Feminino , Linfonodos/patologia , Camundongos , Camundongos Endogâmicos NOD , Terapia de Alvo Molecular , Membro 1 da Família de Moléculas de Sinalização da Ativação Linfocitária , Baço/patologia
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