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1.
J Magn Reson Imaging ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538062

RESUMO

BACKGROUND: Movement disorders such as Parkinson's disease are associated with structural and functional changes in specific brain regions. Advanced magnetic resonance imaging (MRI) techniques combined with machine learning (ML) are promising tools for identifying imaging biomarkers and patterns associated with these disorders. PURPOSE/HYPOTHESIS: We aimed to systematically identify the brain regions most commonly affected in movement disorders using ML approaches applied to structural and functional MRI data. We searched the PubMed and Scopus databases using relevant keywords up to June 2023 for studies that used ML approaches to detect brain regions associated with movement disorders using MRI data. STUDY TYPE: A systematic review and diagnostic meta-analysis. POPULATION/SUBJECTS: Sixty-seven studies with 6,285 patients were included. FIELD STRENGTH/SEQUENCE: Studies utilizing 1.5T or 3T MR scanners and the acquisition of diffusion tensor imaging (DTI), structural MRI (sMRI), functional MRI (fMRI), or a combination of these were included. ASSESSMENT: The authors independently assessed the study quality using the CLAIM and QUADAS-2 criteria and extracted data on diagnostic accuracy measures. STATISTICAL TESTS: Sensitivity, specificity, accuracy, and area under the curve were pooled using random-effects models. Q statistics and the I2 index were used to evaluate heterogeneity, and Begg's funnel plot was used to identify publication bias. RESULTS: sMRI showed the highest sensitivity (93%) and mixed modalities had the highest specificity (90%) for detecting regional abnormalities. sMRI had a 94% sensitivity for identifying subcortical changes. The support vector machine (93%) and logistic regression (91%) models exhibited high diagnostic accuracies. DATA CONCLUSION: The combination of advanced MR neuroimaging techniques and ML is a promising approach for identifying brain biomarkers and affected regions in movement disorders with subcortical structures frequently implicated. Structural MRI, in particular, showed strong performance. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 2.

2.
Pharmacol Rev ; 73(3): 897-923, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34045305

RESUMO

Guanine-rich DNA and RNA sequences can fold into noncanonical nucleic acid structures called G-quadruplexes (G4s). Since the discovery that these structures may act as scaffolds for the binding of specific ligands, G4s aroused the attention of a growing number of scientists. The versatile roles of G4 structures in viral replication, transcription, and translation suggest direct applications in therapy or diagnostics. G4-interacting molecules (proteins or small molecules) may also affect the balance between latent and lytic phases, and increasing evidence reveals that G4s are implicated in generally suppressing viral processes, such as replication, transcription, translation, or reverse transcription. In this review, we focus on the discovery of G4s in viruses and the role of G4 ligands in the antiviral drug discovery process. After assessing the role of viral G4s, we argue that host G4s participate in immune modulation, viral tumorigenesis, cellular pathways involved in virus maturation, and DNA integration of viral genomes, which can be potentially employed for antiviral therapeutics. Furthermore, we scrutinize the impediments and shortcomings in the process of studying G4 ligands and drug discovery. Finally, some unanswered questions regarding viral G4s are highlighted for prospective future projects. SIGNIFICANCE STATEMENT: G-quadruplexes (G4s) are noncanonical nucleic acid structures that have gained increasing recognition during the last few decades. First identified as relevant targets in oncology, their importance in virology is now increasingly clear. A number of G-quadruplex ligands are known: viral transcription and replication are the main targets of these ligands. Both viral and cellular G4s may be targeted; this review embraces the different aspects of G-quadruplexes in both host and viral contexts.


Assuntos
Quadruplex G , Antivirais/farmacologia , Humanos , Ligantes , Estudos Prospectivos
3.
BMC Psychiatry ; 23(1): 220, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-37005577

RESUMO

Family caregivers of dying cancer patients may suffer from grief experiences and bereavement complications. Previous studies have proposed some psycho-emotional interventions for the management of these complications. However, little attention has been given to family-based dignity intervention and expressive writing. This study was conducted to examine the effects of family-based dignity intervention and expressive writing, combined and alone, on anticipatory grief in family caregivers of dying cancer patients. This was a randomized controlled trial, in which 200 family caregivers of dying cancer patients were randomly assigned to four intervention groups: family-based dignity intervention (n = 50), expressive writing intervention (n = 50), combined family-based single dignity intervention and expressive writing (n = 50), and control group (n = 50). In three times (baseline, 1 week, and 2 weeks after the interventions), anticipatory grief was assessed by a 13-item anticipatory grief scale (AGS). Finally, we found a significant reducing effect of family-based dignity intervention on AGS (-8.12 ± 1.53 vs. -1.57 ± 1.52, P = 0.01) and its subscales including behavioral (-5.92 ± 0.97 vs. -2.17 ± 0.96, P = 0.04) and emotional (-2.38 ± 0.78 vs. 0.68 ± 0.77, P = 0.03) subscales compared to the control group. However, no significant effect was seen for expressive writing intervention and combined interventions of expressive writing and family-based dignity intervention. In conclusion, family-based dignity intervention may be a safe intervention for relieving anticipatory grief among family caregivers of dying cancer patients. Additional clinical trials are needed to confirm our findings. Registration number: IRCT20210111050010N1. Trial registration date:2021-02-06.


Assuntos
Luto , Neoplasias , Humanos , Cuidadores/psicologia , Respeito , Pesar , Redação
4.
Proc Natl Acad Sci U S A ; 117(25): 14015-14020, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32518106

RESUMO

The line crack models, including linear elastic fracture mechanics (LEFM), cohesive crack model (CCM), and extended finite element method (XFEM), rest on the century-old hypothesis of constancy of materials' fracture energy. However, the type of fracture test presented here, named the gap test, reveals that, in concrete and probably all quasibrittle materials, including coarse-grained ceramics, rocks, stiff foams, fiber composites, wood, and sea ice, the effective mode I fracture energy depends strongly on the crack-parallel normal stress, in-plane or out-of-plane. This stress can double the fracture energy or reduce it to zero. Why hasn't this been detected earlier? Because the crack-parallel stress in all standard fracture specimens is negligible, and is, anyway, unaccountable by line crack models. To simulate this phenomenon by finite elements (FE), the fracture process zone must have a finite width, and must be characterized by a realistic tensorial softening damage model whose vectorial constitutive law captures oriented mesoscale frictional slip, microcrack opening, and splitting with microbuckling. This is best accomplished by the FE crack band model which, when coupled with microplane model M7, fits the test results satisfactorily. The lattice discrete particle model also works. However, the scalar stress-displacement softening law of CCM and tensorial models with a single-parameter damage law are inadequate. The experiment is proposed as a standard. It represents a simple modification of the three-point-bend test in which both the bending and crack-parallel compression are statically determinate. Finally, a perspective of various far-reaching consequences and limitations of CCM, LEFM, and XFEM is discussed.

5.
Appl Nurs Res ; 74: 151744, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38007245

RESUMO

BACKGROUND: "Partnership Care Model (PCM)", which is the first partnership conceptual framework founded on the Iranian culture to control chronic diseases, has been recently used in different fields of nursing research with no levels of valid evidence to support its application. Therefore, this systematic review and meta-analysis sought to clarify the impacts of interventions developed based on PCM on quality of life (QoL), sleep quality, anxiety, and depression among adults and children with chronic diseases. METHODS: International data sources (e.g., PubMed, Web of Science, Scopus) and national databases (e.g., SID, MagIran, IranDoc, IRCT) were searched from 2001 to September 23, 2023, to find Randomized Controlled Trials (RCTs) on PCM-driven interventions for the experimental groups versus no intervention or standard care groups. The studies' methodological quality and evidence quality were rated utilizing the Cochrane risk of bias instruction and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE). Data were pooled by a random-effects approach employing STATA (vers. 11.2). RESULT: Eighteen RCTs, reported in 22 publications, were qualified. The PCM compared to the standard care significantly improved the QoL among both adults (10 effect sizes [ESs], mean difference [MD]: 3.17, P < 0.001) and children (4 ESs, MD: 4.45, P < 0.001). Likewise, the intervention enhanced adults' sleep quality (3 ESs, MD: 7.15, P < 0.001). The anxiety of adults and children was also significantly lower in the PCM group (4 ESs, MD: -4.52, P = 0.001; 2 ESs, MD: -4.04, P < 0.001, respectively). However, regarding depression, a significant effect of PCM was found only among children (3 ESs, MD: -7.99, P = 0.011). The methodological quality of the studies and the evidence quality were undesirable. CONCLUSION: The PCM had a promising influence on the caring of adults and children suffering from chronic diseases. However, additional high-quality RCTs are needed to generate a higher quality of evidence concerning the clinical benefits of the PCM. PROSPERO NO: CRD42021253790.


Assuntos
Ansiedade , Depressão , Humanos , Adulto , Criança , Ensaios Clínicos Controlados Aleatórios como Assunto , Doença Crônica , Irã (Geográfico) , Qualidade de Vida
6.
Int Nurs Rev ; 70(1): 59-77, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36418147

RESUMO

AIM: This study aimed to clarify the value of caring programs developed according to Orem's Self-Care Deficit Nursing Theory regarding quality of life and self-care as the primary outcomes and self-efficacy, anxiety, depression, and stress as the secondary outcomes among individuals aged 18-70 years with chronic diseases. BACKGROUND: Chronically ill patients need to receive appropriate self-care training, counseling, and support. In this regard, the use of caring programs developed based on theories is highly suggested. Orem's Nursing Theory is the most well-known theory that provides a structure to involve patients in their self-care activities. INTRODUCTION: Orem's Nursing Theory has been increasingly applied to guide practice for patients with chronic health conditions. However, recent trials have reported conflicting findings on the value of its application. METHODS: Eight information sources (e.g., Web of Science Core Collection, PubMed, and Scopus) and the International Clinical Trials Registry Platform were searched up to 30 March 2022. RESULTS: A total of 46 studies and 11 study register entries were eligible. Orem's theory-based interventions significantly improved the quality of life, self-care, and self-efficacy as well as significantly reduced anxiety and depression. However, the value of the interventions on stress was uncertain, as performing the meta-analysis was not possible. DISCUSSION: Orem's Nursing Theory can help nurses in different fields to dynamically and carefully evaluate patients' self-care ability and implement appropriate nursing measures tailored to their needs, interests, and problems. Considering the inconsistent evidence to support the empirical adequacy of this theory, high-quality reviews are essential. CONCLUSION: Orem's theory-based programs had a favorable effect on taking care of adults with chronic diseases. IMPLICATIONS: This study augments the previous reviews related to the applicability of Orem's Nursing Theory. Considering the undesirable evidence quality and the high between-study heterogeneity, further well-designed trials are required to draw an evidence-based conclusion.


Assuntos
Teoria de Enfermagem , Qualidade de Vida , Humanos , Adulto , Autocuidado , Doença Crônica , Autoeficácia
7.
Crit Rev Food Sci Nutr ; 62(5): 1242-1269, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33124897

RESUMO

There is increasing demand from consumers for healthier and more sustainable foods. The marine biosphere is a rich source of health-promoting substances like bioactive peptides, polysaccharides, polyunsaturated lipids, carotenoids, polyphenolic compounds, minerals, saponins, and phytosterols. These substances display a myriad of potentially beneficial biological functions including antioxidant, antimicrobial, anticancer, anti-diabetic, anti-obesity, anti-Alzheimer, anti-fibrotic, neuroprotective, sleep-enhancing, lipid-lowering, wound healing, and skin protection activities. This review provides an update on recent research on bioactive ingredients derived from aquatic sources and highlights their potential application in the food, supplement, and pharmaceutical industries. Key techno-functional and sensorial attributes of these substances are reviewed, as well as their gastrointestinal fate and potential toxicity. This review should provide academia and industry with new insights into the potential application of marine bioactives in products intended to improve human health and wellbeing.


Assuntos
Organismos Aquáticos , Suplementos Nutricionais , Antioxidantes/farmacologia , Humanos , Peptídeos , Polissacarídeos
8.
Biotechnol Appl Biochem ; 69(1): 30-40, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33179788

RESUMO

The necessity and impact of SARS-CoV2 on the world's health have led to developing and producing practical and useful vaccines for this deadly respiratory virus. Since April 2020, a vaccine for the virus has been developed. Given that comorbidities such as diabetes, hypertension, and cardiovascular disease are more prone to viruses and the risk of infection, vaccines should be designed to protect against high-risk respiratory illnesses. Including SARS, MERS, influenza, and the SARS-CoV-2 provide a safe immune response. Here, we review the information and studies that have been done to help develop strategies and perspectives for producing a safe and ideal vaccine to prevent COVID-19 in normal people, especially at high-risk groups such as diabetes patients.


Assuntos
COVID-19 , Diabetes Mellitus , Vacinas contra COVID-19 , Humanos , RNA Viral , SARS-CoV-2
9.
Phytother Res ; 35(12): 6585-6606, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34405933

RESUMO

Recent studies have reported conflicting findings on the antianxiety, antidepressant, and anti-stress properties of Rosa Damascena Mill (RDM). Therefore, the present systematic review and meta-analysis were conducted on the effects of RDM for treating anxiety, depression, and stress amongst adults. The online data sources of Cochrane Central Register of Controlled Trials, PubMed, Scopus, Web of Science, Embase, ProQuest, and Scientific Information Database were searched from inception to June 30, 2021. The randomized controlled trials (RCTs), which examined the effects of RDM (in any form of administration) on adults' anxiety, depression, and stress, were included. A random-effects model was applied to pool the data, and a total of 32 publications were included. The results of the meta-analysis revealed that administration of RDM significantly reduced state anxiety (effect size [ES]: 24, standardized mean difference [SMD]: -1.74, 95% confidence interval [CI]: -2.29, -1.20; p < .001), depression (ES: 7, SMD: -0.87, 95% CI: -1.47, -0.28; p = .004), and stress (ES: 4, SMD: -1.33, 95% CI: -1.98, -0.69; p < .001). However, the treatment had no significant effect on trait anxiety (ES: 6, weighted mean difference: -0.75, 95% CI: -1.93, 0.43; p = .214). The association between the total administration dosage and/or duration of RDM and the changes in state anxiety and depression was not dose-dependent. Most RCTs had a fair methodological quality based on the Cochrane risk of bias assessment tool. Besides, the quality of evidence ranged from very low to moderate according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Hence, further high-quality RCTs are needed to draw reliable conclusions regarding the use of RDM for treating adults' anxiety, depression, and stress.


Assuntos
Depressão , Rosa , Adulto , Ansiedade/tratamento farmacológico , Transtornos de Ansiedade/tratamento farmacológico , Depressão/tratamento farmacológico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Geriatr Nurs ; 42(1): 78-82, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33302002

RESUMO

The current study aimed to investigate the effects of a Namaste care program on the quality of life of 25 women with late-stage Alzheimer's disease. The program was implemented two hours daily and four days per week for six months in a nursing facility, Tehran, Iran. Women's quality of life was measured using the Persian version of the Quality of Life in Late-Stage Dementia scale before and after the program implementation. After a six-month intervention with the Namaste care program, the total score of quality of life significantly decreased (17.79 ± 1.10 at the end of trial compared with 24.67 ± 1.62 at baseline, P = 0.01), indicating improved quality of life. This effect was obtained after controlling for demographic variables and comorbidities. Hence, it seems that the Namaste care program might be an effective supportive method to improve the quality of life of women with late-stage Alzheimer's disease in Iranian culture. However, further large-sample studies are needed to investigate the generalizability of the findings.


Assuntos
Doença de Alzheimer , Demência , Feminino , Humanos , Irã (Geográfico) , Casas de Saúde , Projetos Piloto , Qualidade de Vida
12.
Support Care Cancer ; 28(1): 405-411, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31418073

RESUMO

BACKGROUND AND OBJECTIVES: Cancer is usually associated with decreased self-esteem. Relaxation is one of the most effective methods to promote self-esteem of patients with chronic diseases. Hence, the present study aimed to investigate the effects of relaxation on self-esteem of patients with cancer. METHODS: This randomized clinical trial was conducted on 80 patients with cancer. The samples were selected by convenience sampling method and were randomly divided into experimental and control groups. In the experimental group, the patients implemented relaxation techniques once a day for 30 min during 60 consecutive days in addition to receiving routine care, while patients in the control group received only routine care. Before and after the intervention, the Persian version of the Coopersmith Self-Esteem Inventory (CSEI) was completed. RESULTS: After the interventions, significant differences were observed between groups in favor of the relaxation group in total score of CSEI and all its subscales (P = 0.0001). In the experimental group, a significant increase in total score and all subscales of CSEI was observed after the intervention (P = 0.001), whereas in the control group, a significant decrease was found in all dimensions (P = 0.001). CONCLUSION: The relaxation seems to be potentially effective in promoting self-esteem of patients with cancer. Further studies, particularly randomized clinical trials with higher sample size and more power, are needed to confirm the obtained findings.


Assuntos
Neoplasias/psicologia , Neoplasias/terapia , Terapia de Relaxamento , Autoimagem , Adulto , Sobreviventes de Câncer/psicologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Inventário de Personalidade , Terapia de Relaxamento/métodos , Terapia de Relaxamento/psicologia , Autoeficácia
13.
J Perianesth Nurs ; 35(5): 533-538, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32386940

RESUMO

PURPOSE: This study compared the effects of Benson relaxation with progressive muscle relaxation on pain severity after laminectomy. DESIGN: Three-arm randomized, nonblinded, and parallel group trial. METHODS: The study was conducted with 93 patients who underwent lumbar laminectomy. Patients were randomly assigned to three groups of Benson relaxation + routine care (n = 31), progressive muscle relaxation + routine care (n = 31), and routine care (n = 31). The two relaxation methods were performed at 2 (time 1), 12 (time 2), and 24 (time 3) hours after patients' regaining full consciousness in postoperative wards. Pain severity was assessed using the visual analog scale once before laminectomy, before and also 20 minutes after each relaxation session. In the control group, pain severity was measured at the same times as in the two relaxation groups. FINDINGS: Both Benson relaxation and progressive muscle relaxation resulted in a significant reduction in pain severity in comparison with the control group at all three measurement times (except at time 1 in the progressive muscle relaxation group). However, no significant differences were found between Benson relaxation and progressive muscle relaxation in any of the three times. CONCLUSIONS: The results suggest that both Benson and progressive muscle relaxation techniques can decrease acute postlaminectomy pain in the immediate postoperative period in adult patients.


Assuntos
Dor , Terapia de Relaxamento , Adulto , Humanos , Medição da Dor , Dor Pós-Operatória , Período Pós-Operatório , Resultado do Tratamento
14.
J Food Sci Technol ; 56(8): 3777-3789, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31413404

RESUMO

This study aimed to investigate the performance of equal amounts of edible green seaweed, Ulva intestinalis powder (2.77 g kg-1), and its sulphated polysaccharide ([USP], 0.5 g kg-1, based on the extraction yield from U. intestinalis powder) on the proximate compositions, lipid oxidation, pH, colour, textural properties, cooking yield and sensory attributes of fish-surimi restructured products during storage at - 18 °C as compared with the control. Results showed incorporation of two functional components resulted in lower TBARS values compared with the control over 6 months (P ≤ 0.05). The USP incorporated fingers showed the least moisture loss over 6 months (P < 0.05). Textural properties for two functional fingers remained relatively stable from month 0 to month 6, while the hardness increased significantly (P < 0.05) in the control fingers (67 to 80 N). Additionally, the sensory attributes of all formulated fingers were judged acceptable; however, the USP containing fingers were preferred by the sensory panelists, due to their juicy texture as a result of less cooking loss comparing with others. In conclusion, this study suggests the potential use of such natural marine ingredients to maintain the quality and to extend the shelf life of surimi-based products with beneficial health effects.

15.
J Food Sci Technol ; 56(3): 1212-1220, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30956301

RESUMO

Sulfated polysaccharide (fucoidan) was isolated from Nizamuddinia zanardinii by enzyme (alcalase), ultrasonic and enzyme-ultrasonic methods. The extracted fucoidans were assessed for their chemical compositions, molecular characteristics, anticancer and immunomodulatory activities. Enzyme-ultrasonic isolated fucoidan showed the maximum extraction yield (7.87%) while that obtained by ultrasonic had the minimum value (3.6%). fucoidans were composed of different levels of carbohydrates (52.78-58.65%), proteins (6.98-8.91%), sulfates (21.78-29.6%) and uronic acids (0.42-1.08%). The weight mean average molecular weight of fucoidans varied between 443.7 and 1020.85 kDa. The polysaccharide chains were consisted of fucose, galactose, glucose, mannose and xylose. All the recovered fucoidans showed strong growth inhibition against HeLa and Hep-G2 cancer cells. The isolated fucoidans were non-toxic and considerably stimulated the macrophage cells to release nitric oxide. Enzyme extraction produced fucoidan with the most macrophage stimulation capacity (> 42 µmol). These results suggested that enzyme treatment preserved more sulfate groups in fucoidan structure influencing its anticancer and immunostimulatory activities.

17.
J Food Sci Technol ; 55(11): 4650-4660, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30333662

RESUMO

Water-soluble polysaccharides were isolated from Colpomenia peregrina to determine their chemical characteristics and immunomodulatory properties. High extraction yields were obtained for CP1 (17.6%) and CP2 (5.2%) polysaccharides. Polysaccharides were mainly consisted of neutral sugars (67.01-73.79%), uronic acids (9.43-14.89%), proteins (3.44-14.89%) and small amounts of sulfates (4.87-4.91%). Polysaccharides were composed of fucose (20.62-24.56%), galactose (25.5-26.94%) and glucose (50.00-52.91%) residues. The average molecular weights of the CP1 and CP2 polysaccharides were 1890 × 103 g/mol and 639 × 103 g/mol, respectively. The polysaccharides exerted a relatively low cytotoxicity against HeLa cancer cells (< 40%). The CP1 and CP2 polysaccharides were nontoxic and induced RAW264.7 murine macrophage cells to release considerable amounts of nitric oxide (NO). Inflammatory cytokines including IL-1ß, TNF-α, IL-6, IL-10 and IL-12 from were secreted from RAW264.7 cells induced with CP1 polysaccharides. As the most immunostimulating fraction, CP1 polysaccharides were homogeneous and formed of 1,3-linked galactose, 1,4-linked glucose and 1,3-linked fucose residues. Overall, these findings suggested that the polysaccharides isolated from C. peregrina can be utilized as potential natural immunostimulant in functional foods or pharmaceutical industries.

18.
J Food Sci Technol ; 54(12): 4016-4025, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29085144

RESUMO

The effect of polymer degradation was studied on immunomodulatory and antioxidant properties of fucoidan isolated from S. angustifolium. Partially hydrolyzed fucoidans were prepared using 0.01 N hydrochloric acid after incubation for 10 and 15 min in boiling water. FT-IR analysis showed two major peaks at 850 cm-1 corresponding to bending vibration of C-O-S of sulfate and 1256 cm-1 derived from the stretching vibration of S-O. The native fucoidan consisted mainly of carbohydrate (49.4%), sulfate (22.9%), uronic acid (10.3%) and minor amount of protein (4.1%). The hydrolysis reduced the molecular weight of native fucoidan from 421 × 103 g/mol to 104.1 × 103 g/mol after 10 min boiling and 63.9 × 103 g/mol after 15 min boiling, without a significant change in their chemical compositions. Acid degradation increased the specific volume of gyration from 0.84 to 3.32 cm3/g in hydrolyzed fucoidan polymers. Fucoidan with the lowest molecular weight showed the greatest proliferating effect on RAW264.7 cells and induced the macrophage cells to release more nitric oxide (39.0 µmol) at 50 µg/mL. The DPPH radical scavenging activity, ABTS radical scavenging activity and reducing power remarkably increased after hydrolysis. The current results showed that molecular weight has determinant effect on immunomodulatory and antioxidant activities of unrefined fucoidan and thus acid hydrolysis can be applied on commercial scale to obtain fucoidans with more beneficial effects.

19.
J Food Sci Technol ; 53(1): 521-30, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26787971

RESUMO

Essential oils of clove, coriander, caraway, marjoram, cinnamon, and cumin were tested for their antilisterial activity by application of agar diffusion assay (experiment 1). Marjoram essential oil (MEO) showed the highest inhibitory effect, followed by clove and cinnamon. Subsequently, these essential oils were incorporated to alginate/clay nanocomposite films and antilisterial effectiveness of the films was studied in a model solid food system during 12 days at 10 °C (experiment 2). The results revealed that the films with MEO were more effective against Listeria monocytogenes in the model step. Finally, alginate-clay film incorporating 1 % MEO was applied to inoculated trout slices during refrigerated storage (4 °C) for 15 days (experiment 3). The control and the wrapped fish samples were analyzed periodically for microbiological (L. monocytogenes, total viable count, psychrotrophic count) and chemical (TVB-N) properties. The results demonstrated that alginate-clay films enriched with 1 % MEO significantly delayed the growth of L. monocytogenes during the 15-day storage with final counts reaching 6.23 log CFU/g while the counts in control samples were significantly higher reaching 7.38 log CFU/g (p < 0.05). Furthermore, active films efficiently reduced total viable count and psychrotrophic count as well as TVB-N in the fish slice during refrigerated storage.

20.
J Food Sci Technol ; 52(5): 2974-81, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25892798

RESUMO

The potential of antioxidant activity of the green algae (Chaetomorpha sp.) was studied in this work. The optimum processing conditions for the extraction of antioxidant compounds from dried green algae were determined using response surface methodology (RSM). A central composite design (CCD) was applied to determine the effects of three process variables as follows: solvent concentration (percent), extraction time (min) and microwave power (w) on total phenolic contents, ferric reducing power, 2'2-dipheny-l-picrylhydrazyl (DPPH) radical scavenging activity and total antioxidant capacity assays. The independent variables were coded at five levels and CCD included 20 experimental runs with six replications at the center point. The statistical analysis of data was performed using design expert software and second-order polynomial models generated after analysis of variance (ANOVA) applied for predicting the responses. The results revealed that the highest total phenol content and reducing power were 1.09 and 0.12 mg of tannic acid equivalent/g dry weight, respectively. The maximum antioxidant activity was 0.19 mg ascorbic acid equivalent/g dry weight and DPPH was 99.8 % under MAE. The optimum conditions using RSM for the predicted responses were: microwave power 300 W, extraction time 8 min and solvent concentration 25 %, respectively. Furthermore the actual experimental values were adjacent to the corresponding predicted values which demonstrated fitness of the employed models and suitability of RSM in extraction parameters optimization.

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