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1.
Folia Phoniatr Logop ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38574489

RESUMO

PURPOSE: The purpose of this study was to explore the effect of a lingual resistance training protocol on the swallowing function of an individual presenting with dysphagia and reduced tongue pressures following a supratentorial ischemic stroke. METHODS: A study involving a lingual resistance training protocol with videofluoroscopy to measure outcomes comparing different parameters to ASPEKT normative reference values at three timepoints: baseline (VFSS A), following a 4-week lead-in period to control for spontaneous recovery (VFSS B), and at the 8-week endpoint of treatment (VFSS C). The study was interrupted due to the COVID-19 pandemic after 1 participant enrollment and is presented as single case study. RESULTS: Isometric tongue pressures: Following the 4-week lead-in, a decline in maximum isometric anterior tongue pressure (MAIP) and regular effort saliva swallow pressures (RESS) was noted, however there was no change in maximum posterior isometric tongue pressures (MPIP). Isometric tongue pressures improved post-treatment, with increases in MAIP, MPIP, and to a lesser degree RESS. Swallowing Function: Impairments in swallowing safety continued between the baseline VFSS A (Penetration-Aspiration Scale score [PAS]=8) and lead-in VFSS B (PAS=5). Swallowing safety improved following the intervention, with PAS scores = 1 at the endpoint VFSS C. Pixel-based measures of swallowing efficiency revealed a reduced frequency of post-swallow total pharyngeal reside following the treatment. Improvements were found in two other swallowing parameters, laryngeal vestibule closure integrity and pharyngeal area at maximum pharyngeal constriction, at the endpoint VFSS. CONCLUSION: These pilot data suggest improvements in some swallowing parameters as an outcome of intervention.

2.
J Speech Lang Hear Res ; 66(3): 863-871, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36780312

RESUMO

PURPOSE: Videofluoroscopic (VFSS) measurements of pharyngeal swallow mechanics can differentiate age- and disease-related changes in swallowing. Pharyngeal area at rest (PhAR) may differ in people with dysphagia, although its impact is not clear. Before the role of PhAR in dysphagia can be explored, it is important to establish whether PhAR remains stable across repeated measures in healthy adults, and varies as a function of sex or age. We hypothesized that healthy adults would show stable PhAR across repeated measures, but that larger PhAR would be seen in men versus women and in older versus younger adults. METHOD: We collected VFSS data from 87 healthy adults (44 men, M age = 46 years, range: 21-82). Trained raters identified the swallow rest frame after the initial swallow of each bolus and measured unobliterated pharyngeal area on these frames, in %(C2-4)2 units. Repeated-measures analyses of variance with a factor of sex, a covariate of age, and a repeated factor of task repetition were performed across the first 12 available measures per participant (N = 1,044 swallows). RESULTS: There were no significant variations in PhAR across repeated measures. A significant Sex × Age interaction was seen (p = .04): Males had significantly larger PhAR than females (p = .001), but females showed larger PhAR with advancing age (R = .47). CONCLUSIONS: These data confirm stability in PhAR across repeated measurements in healthy individuals. However, significant sex and age differences should be taken into consideration in future studies exploring the role of PhAR in people with dysphagia. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.22043543.


Assuntos
Transtornos de Deglutição , Adulto , Masculino , Humanos , Feminino , Idoso , Pessoa de Meia-Idade , Transtornos de Deglutição/diagnóstico por imagem , Faringe/diagnóstico por imagem , Deglutição , Cinerradiografia , Fluoroscopia
3.
Am J Speech Lang Pathol ; 32(2): 688-700, 2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36812476

RESUMO

PURPOSE: In this article, we illustrate use of a systematic approach to rating videofluoroscopic swallowing studies (VFSS), the Analysis of Swallowing Physiology: Events, Kinematics and Timing (ASPEKT) method. The method is applied to a clinical case series of individuals with a history of traumatic spinal cord injury (tSCI) requiring surgical intervention using a posterior approach. Previous studies suggest that swallowing is highly variable in this population given heterogeneity in mechanisms, location and extent of injury, and in surgical management approaches. METHOD: The case series involved 6 individuals who were at least 1 month postsurgery for management of tSCI. Participants completed a VFSS using a standardized bolus protocol. Each VFSS was blindly rated in duplicate using the ASPEKT method and compared with published reference values. RESULTS: The analysis revealed considerable heterogeneity across this clinical sample. Penetration-aspiration scale scores of 3 or higher were not observed in this cohort. Of note, patterns of impairment did emerge, suggesting there are some commonalities across profiles in this population, including the presence of residue associated with poor pharyngeal constriction, reduced upper esophageal opening diameter, and short upper esophageal sphincter opening duration. CONCLUSIONS: Although the participants in this clinical sample shared a history of tSCI requiring surgical intervention using a posterior approach, there was great heterogeneity in swallowing profile. Using a systematic method to identify atypical swallowing parameters can guide clinical decision making for determining rehabilitative targets and measuring swallowing outcomes.


Assuntos
Transtornos de Deglutição , Fluoroscopia , Traumatismos da Medula Espinal , Humanos , Deglutição , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/etiologia , Fluoroscopia/métodos , Valores de Referência , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/cirurgia , Gravação em Vídeo
4.
Comput Methods Programs Biomed ; 225: 107058, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35961072

RESUMO

BACKGROUND AND OBJECTIVE: The videofluoroscopic swallowing study (VFSS) is a gold-standard imaging technique for assessing swallowing, but analysis and rating of VFSS recordings is time consuming and requires specialized training and expertise. Researchers have recently demonstrated that it is possible to automatically detect the pharyngeal phase of swallowing and to localize the bolus in VFSS recordings via computer vision approaches, fostering the development of novel techniques for automatic VFSS analysis. However, training of algorithms to perform these tasks requires large amounts of annotated data that are seldom available. In this paper, we demonstrate that the challenges of pharyngeal phase detection and bolus localization can be solved together using a single approach. METHODS: We propose a deep-learning framework that jointly tackles pharyngeal phase detection and bolus localization in a weakly-supervised manner, requiring only the initial and final frames of the pharyngeal phase as ground truth annotations for the training. Our approach stems from the observation that bolus presence in the pharynx is the most prominent visual feature upon which to infer whether individual VFSS frames belong to the pharyngeal phase. We conducted extensive experiments with multiple convolutional neural networks (CNNs) on a dataset of 1245 bolus-level clips from 59 healthy subjects. RESULTS: We demonstrated that the pharyngeal phase can be detected with an F1-score higher than 0.9. Moreover, by processing the class activation maps of the CNNs, we were able to localize the bolus with promising results, obtaining correlations with ground truth trajectories higher than 0.9, without any manual annotations of bolus location used for training purposes. CONCLUSIONS: Once validated on a larger sample of participants with swallowing disorders, our framework will pave the way for the development of intelligent tools for VFSS analysis to support clinicians in swallowing assessment.


Assuntos
Líquidos Corporais , Transtornos de Deglutição , Deglutição/fisiologia , Transtornos de Deglutição/diagnóstico por imagem , Fluoroscopia/métodos , Humanos , Faringe/diagnóstico por imagem
5.
J Speech Lang Hear Res ; 65(7): 2399-2411, 2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35731684

RESUMO

PURPOSE: Patients with poststroke dysphagia may experience inefficient bolus clearance or inadequate airway protection. Following a stroke, impairments in lingual pressure generation capacity are thought to contribute to oropharyngeal dysphagia. The goal of our study was to determine whether similar profiles of swallowing impairment would be seen across a cohort of patients with reduced tongue strength within 3 months after cerebral ischemic stroke. METHOD: The sample comprised six adults with reduced tongue strength (i.e., maximum anterior isometric pressure < 40 kPa). Participants underwent a videofluoroscopy according to a standard protocol. Post hoc blinded ratings were completed using the Analysis of Swallowing Physiology: Events, Kinematics and Timing Method and coded as "typical" versus "atypical" (i.e., within vs. outside the healthy interquartile range) in comparison to published reference values. RESULTS: The videofluoroscopies suggested that having reduced tongue strength did not translate into a common profile. Of the six participants, two showed Penetration-Aspiration Scale (PAS) scores of ≥ 3 on thin liquids, associated with incomplete laryngeal vestibule closure (LVC). Another two participants displayed PAS scores of 2 (transient penetration), but these were not associated with incomplete LVC. Pharyngeal residue, above the healthy 75th percentile, was seen for three participants. Five participants presented with atypical reductions in hyoid XY peak position. CONCLUSIONS: In this cohort of adults within 3 months of cerebral ischemic stroke, reductions in tongue strength presented alongside a variety of changes in swallowing physiology. There was no straightforward relationship linking reduced tongue strength to particular patterns of impairment on videofluoroscopy.


Assuntos
Transtornos de Deglutição , AVC Isquêmico , Acidente Vascular Cerebral , Adulto , Deglutição/fisiologia , Transtornos de Deglutição/complicações , Transtornos de Deglutição/etiologia , Humanos , Acidente Vascular Cerebral/complicações , Língua/diagnóstico por imagem
6.
J Speech Lang Hear Res ; 65(2): 419-430, 2022 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-34982956

RESUMO

PURPOSE: Research remains equivocal regarding the links between hyoid movement and penetration-aspiration. The aims of this study were (a) to explore associations between hyoid parameters, laryngeal vestibule closure (LVC) parameters, and penetration-aspiration on thin liquids; and (b) to determine which of these parameters are the strongest predictors of penetration-aspiration. METHOD: This study involved retrospective analysis of an existing videofluoroscopy data set, collected in 305 participants (152 males) with noncongenital/nonsurgical/non-oncological risk for dysphagia. We extracted data for six thin liquid swallows per participant, and obtained measures of hyoid movement (peak position, speed) and LVC (complete/incomplete, timing, duration). Resulting values were coded as typical/atypical relative to healthy reference data. Relationships were explored using chi-square tests and odds ratios (a) for the entire data set and (b) for the subset of data with complete LVC. Hierarchical logistic regression models determined the strongest predictors of penetration-aspiration. RESULTS: Significant associations were found between penetration-aspiration and incomplete LVC, prolonged time-to-most-complete-LVC, short LVC duration, reduced anterior hyoid peak position, and reduced hyoid speed. Hyoid measures were also significantly associated with LVC parameters. In the first regression model, incomplete LVC and prolonged time-to-most-complete-LVC were the only significant predictors of penetration-aspiration. For cases with complete LVC, the only significant predictor was prolonged time-to-most-complete-LVC. CONCLUSIONS: Although reduced anterior hyoid peak position and speed are associated with penetration-aspiration on thin liquids, these measures do not independently account for penetration-aspiration when considered in conjunction with measures of LVC. When identifying mechanisms explaining penetration-aspiration, clinicians should focus on LVC (complete/incomplete) and timeliness of LVC.


Assuntos
Transtornos de Deglutição , Deglutição , Fenômenos Biomecânicos , Cinerradiografia/métodos , Transtornos de Deglutição/diagnóstico por imagem , Fluoroscopia , Humanos , Osso Hioide/diagnóstico por imagem , Masculino , Estudos Retrospectivos
7.
OBM Geriat ; 5(1)2021.
Artigo em Inglês | MEDLINE | ID: mdl-34350402

RESUMO

Research suggests there are age-related changes in swallowing that do not constitute impairment ("presbyphagia"). The goal of this study was to explore the influence of age on quantitative measures of healthy swallowing by controlling for the effects of sex and sip volume in order to determine the specific characteristics of presbyphagia. Videofluoroscopy recordings of thin liquid swallows from 76 healthy adults (38 male), aged 21-82 were analysed. Blinded duplicate ratings of swallowing safety, efficiency, kinematics, and timing were made using the ASPEKT method. Hierarchical regression models were used to determine the effects of age, sex, and sip-volume on swallowing. There were no age-related changes in sip volume, number of swallows per bolus, frequency or severity of penetration-aspiration, duration of the hyoid-burst (HYB)-to-upper-esophageal-sphincter (UES) opening interval, time-to-laryngeal-vestibule-closure (LVC), peak hyoid position, hyoid speed, or pharyngeal residue. Significant changes seen with increasing age included: longer swallow reaction time, UES opening duration and LVC duration; larger pharyngeal area at rest and maximum constriction; and wider UES diameter. Male participants had larger sip volume and pharyngeal area at rest. Larger sip volumes were associated with multiple swallows per bolus and shorter hyoid-burst-to-UES opening intervals. These results help to define presbyphagic changes in swallowing that can be expected in healthy older adults up to 80 years of age, and distinguish them from changes that represent impairment. Certain parameters showed changes that were opposite in direction to changes that are usually considered to reflect impairment: longer UES opening, longer LVC duration and wider UES opening. These changes may reflect possible compensations for slower bolus transit. Further research is needed to determine the points along the age continuum where observed age-related changes in swallowing begin to emerge.

8.
J Speech Lang Hear Res ; 64(1): 51-58, 2021 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-33270468

RESUMO

Purpose Judgments regarding hyoid movement are frequently included in evaluations of swallowing. However, the literature lacks reference values for measures of hyoid kinematics in healthy swallowing. This study explores hyoid movement across the continuum from thin to extremely thick liquids. Method Participants were 39 healthy adults under the age of 60 years (19 men) who underwent videofluoroscopy involving three sips each of 20% w/v thin barium and six sips each of slightly, mildly, moderately, and extremely thick barium. Half of the thickened stimuli were prepared using xanthan gum; and half, with a starch-based thickener. Sip volume was derived from pre- and post-sip cup weights. Hyoid position was tracked frame-by-frame relative to the anterior-inferior corner of C4. Measures of peak hyoid position (along the XY axis) were normalized to a C2-C4 scalar, and measures of time-to-peak position, speed, and time-to-peak speed were derived. As a first step, Spearman's correlations confirmed the influence of sip volume on these hyoid measures. Linear mixed-effects models then explored the effects of stimulus, sip volume, and task repetition on the dependent variables. Results The data set comprised 975 swallows with available hyoid tracking data. Sip volume was correlated with peak hyoid XY position (rs = .15, p < .01), time-to-peak position (rs = -.15, p < .05), and speed (rs = .13, p < .01). No significant differences in hyoid kinematics were found across stimuli. Conclusion Measures of hyoid movement in healthy swallowing remain stable across the range from thin to extremely thick liquids with no systematic alterations in hyoid position or kinematics.


Assuntos
Transtornos de Deglutição , Deglutição , Adulto , Fenômenos Biomecânicos , Cinerradiografia , Humanos , Osso Hioide/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade
9.
J Speech Lang Hear Res ; 63(11): 3643-3658, 2020 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-33105085

RESUMO

Purpose Dysphagia is a serious extra pulmonary manifestation of chronic obstructive pulmonary disease (COPD). However, the nature of abnormalities in swallowing physiology in COPD has yet to be clearly established. We explored the frequency of swallowing measures outside the healthy reference range in adults with COPD. Method Participants were 28 adults aged 41-79 years (18 men, 20 women) with stable COPD. Disease severity was classified as GOLD (Global Initiative For Chronic Obstructive Lung Disease) Stages 1 (4%), 2 (25%), 3 (53%), and 4 (18%). Participants underwent a videofluoroscopy and swallowed 20% w/v thin barium in, followed by 20% w/v mildly, moderately, and extremely thick barium prepared with a xanthan gum thickener. Blinded duplicate ratings of swallowing safety, efficiency, kinematics, and timing were performed according to the ASPEKT method (Analysis of Swallowing Physiology: Events, Kinematics and Timing). Comparison data for healthy adults aged < 60 years were extracted from an existing data set. Chi-square and Fisher's exact tests compared the frequencies of measures falling < 1 SD/ > 1 SD from mean reference values (or < the first or > the third quartile for skewed parameters). Results Participants with COPD did not display greater frequencies of penetration-aspiration, but they were significantly more likely (p < .05) to display incomplete laryngeal vestibule closure (LVC), longer time-to-LVC, and shorter LVC duration. They also displayed significantly higher frequencies of short upper esophageal sphincter opening, reduced pharyngeal constriction, and pharyngeal residue. Conclusion This analysis reveals differences in swallowing physiology in patients with stable COPD characterized by impaired safety related to the mechanism, timing, and duration of LVC and by impaired swallowing efficiency with increased pharyngeal residue related to poor pharyngeal constriction.


Assuntos
Transtornos de Deglutição , Doença Pulmonar Obstrutiva Crônica , Adulto , Cinerradiografia , Deglutição , Transtornos de Deglutição/diagnóstico por imagem , Transtornos de Deglutição/etiologia , Feminino , Fluoroscopia , Humanos , Masculino , Índice de Gravidade de Doença
10.
Am J Speech Lang Pathol ; 29(1): 335-356, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-31999193

RESUMO

Purpose Expiratory muscle strength training (EMST) is increasingly utilized in dysphagia rehabilitation; however, little is known about the effects of this approach on swallowing function or physiology. We conducted a systematic review to appraise and synthesize evidence regarding the effects of EMST on videofluoroscopic measures of swallowing in individuals with medical diagnoses, in which dysphagia is a concern. Method A literature search was conducted according to Cochrane guidelines. Of 292 nonduplicate articles, 11 were judged to be relevant for review. These underwent detailed review for study quality, risk of bias evaluation, and synthesis of swallowing outcomes. Results The selected articles described EMST in a variety of patient populations using either the EMST150 or the Phillips Threshold positive expiratory pressure device. The typical protocol involved five sets of five breaths through the device (25 breaths/day), 5 days per week for 4 weeks. Exercise loads were set between 50% and 75% depending on the population, and treatment was typically supervised by a clinician weekly. The Penetration-Aspiration Scale was the most commonly reported videofluoroscopic outcome measure. Conclusions differed as to whether or not swallowing improved following a course of EMST. Differences in videofluoroscopy protocols, methods of summarizing participant performance, and statistical approaches across studies meant that meta-analysis of swallowing outcomes could not be completed. Conclusion This review failed to find clear evidence regarding the effects of EMST on videofluoroscopic measures of swallowing. Heterogeneity in the etiologies and baseline severity of dysphagia across studies and in the methods used to measure swallowing outcomes was a particular barrier to data synthesis.


Assuntos
Transtornos de Deglutição/terapia , Deglutição/fisiologia , Treinamento Resistido/métodos , Músculos Respiratórios/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Transtornos de Deglutição/diagnóstico por imagem , Transtornos de Deglutição/etiologia , Fluoroscopia/métodos , Humanos , Pessoa de Meia-Idade , Força Muscular/fisiologia , Músculos Respiratórios/diagnóstico por imagem
11.
Dysphagia ; 35(5): 745-761, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31612288

RESUMO

Lingual resistance training has been proposed as an intervention to improve decreased tongue pressure strength and endurance in patients with dysphagia. However, little is known about the impact of lingual resistance training on swallow physiology. This systematic review scrutinizes the available evidence regarding the effects of lingual resistance training on swallowing function in studies using Videofluoroscopic Swallowing Studies (VFSS) with adults. Seven articles met the inclusion criteria and underwent detailed review for study quality, data extraction, and planned meta-analysis. Included studies applied this intervention to a stroke and brain injury patient populations or to healthy participants, applied different training protocols, and used a number of outcome measures, making it difficult to generalize results. Lingual resistance training protocols included anterior and posterior tongue strengthening, accuracy training, and effortful press against hard palate with varying treatment durations. VFSS protocols typically included a thin barium stimulus along with one other consistency to evaluate the effects of the intervention. Swallowing measures included swallow safety, efficiency, and temporal measures. Temporal measures significantly improved in one study, while safety improvements showed mixed results across studies. Reported improvements in swallowing efficiency were limited to reductions in thin liquid barium residue in two studies. Overall, the evidence regarding the impact of lingual resistance training for dysphagia is mixed. Meta-analysis was not possible due to differences in methods and outcome measurements across studies. Reporting all aspects of training and details regarding VFSS protocols is crucial for the reproducibility of these interventions. Future investigations should focus on completing robust analyses of swallowing kinematics and function following tongue pressure training to determine efficacy for swallowing function.


Assuntos
Transtornos de Deglutição , Treinamento Resistido , Adulto , Deglutição , Transtornos de Deglutição/terapia , Humanos , Pressão , Reprodutibilidade dos Testes , Língua/diagnóstico por imagem
12.
J Speech Lang Hear Res ; 62(5): 1338-1363, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31021676

RESUMO

Purpose Thickened liquids are frequently used as an intervention for dysphagia, but gaps persist in our understanding of variations in swallowing behavior based on incremental thickening of liquids. The goal of this study was to establish reference values for measures of bolus flow and swallowing physiology in healthy adults across the continuum from thin to extremely thick liquids. Method A sex-balanced sample of 38 healthy adults underwent videofluoroscopy and swallowed 20% weight-to-volume concentration barium prepared in thin and slightly, mildly, moderately, and extremely thick consistencies using a xanthan gum thickener. Participants took comfortable sips and swallowed without a cue; sip volume was measured based on presip and postsip cup weights. A standard operating procedure (the ASPEKT method: Analysis of Swallowing Physiology: Events, Kinematics and Timing) was used to analyze videofluoroscopy recordings. Results The results clarify that, for thin liquid sips (10-14 ml), a single swallow without clearing swallows is typical and is characterized by complete laryngeal vestibule closure, complete pharyngeal constriction, and minimal postswallow residue. Aspiration was not seen, and penetration was extremely rare. Bolus position at swallow onset was variable, extending as low as the pyriform sinuses in 37% of cases. With thicker liquids, no changes in event sequencing, laryngeal vestibule closure, pharyngeal constriction, or postswallow residue were seen. The odds of penetration were significantly reduced. A longer timing interval until onset of the hyoid burst movement was seen, with an associated higher bolus position at swallow onset. Other timing measures remained unaffected by changes in bolus consistency. Conclusion The results include new reference data for swallowing in healthy adults across the range from thin to extremely thick liquids.


Assuntos
Deglutição/fisiologia , Adulto , Sulfato de Bário/administração & dosagem , Meios de Contraste/administração & dosagem , Feminino , Aditivos Alimentares/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Polissacarídeos Bacterianos/administração & dosagem , Valores de Referência , Adulto Jovem
13.
Bioorg Med Chem ; 16(20): 9238-46, 2008 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-18823782

RESUMO

The generated wastewater of table-olive brine processing contains a high amount of polyphenols which are endowed with interesting biological activities. The ethyl acetate extract (EAE) of such wastewater shows high hydroxytyrosol (HT) and tyrosol concentrations of 690 and 98 mg g(-1) dry weight extract, respectively. Phenolic compounds analysis was performed by gas chromatography-mass spectrometry (GC-MS). The antioxidant activity was evaluated by the scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2'-Azinobis[3-ethylbenzothiazoline-6-sulfonate] radicals. Total polyphenol content was estimated with the Folin-Ciocalteu assay. Hydroxytyrosol has DPPH and ABTS radicals scavenging activities higher than 2,6-di-tert-butyl-hydroxytoluene (BHT), while triacetylated hydroxytyrosol (triAcHT) was devoid of any antioxidant activity. The assessment of these antioxidant compounds in biological systems was carried out by the determination of their in vitro cytotoxicity against two different human cancer cell lines (HeLa and DG75) and normal peripheral blood lymphocytes (PBL) using the MTT assay. The 50% cytotoxic concentrations were ranged between 27 and 210 microg mL(-1) for Hela and DG75. At the same concentration range, the EAE and the pure HT and triAcHT exhibited an insignificant cytotoxicity against PBL. Incubation of HeLa and DG75 cells with non-cytotoxic concentrations of EAE, HT or triAcHT resulted in a remarkable protection from the oxidative stress induced by Fe(2+). The antimicrobial activity evaluated by the broth dilution NCCL method using Gram-positive (Staphylococcus aureus, Bacillus subtilis) and Gram-negative (Pseudomonas aeruginosa, Escherichia coli, Salmonella enterica) bacteria and (Candida albicans, Aspergillus niger) fungi showed a broad spectrum bactericidal and fungicidal effect of table-olives-EAE, HT and triAcHT. The MICs vary from 125 to 500 microg mL(-1) for bacteria and from 500 to 2000 microg mL(-1) for fungi.


Assuntos
Olea/química , Fenol/síntese química , Fenol/isolamento & purificação , Sais/química , Poluentes Químicos da Água/química , Acetatos/química , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fenômenos Químicos , Humanos , Viabilidade Microbiana/efeitos dos fármacos , Estrutura Molecular , Fenol/química , Fenol/farmacologia , Eliminação de Resíduos Líquidos
14.
Appl Biochem Biotechnol ; 151(1): 71-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18785022

RESUMO

The lipase inhibitory activity of ethanol extracts obtained from some marine algae collected on the Tunisian coast was evaluated. Caulerpa prolifera extract markedly reduced both dog gastric (DGL) and human pancreatic lipase (HPL) activities. Generally, the inhibition reached 100% after 40 to 60 min of incubation depending on lipase types and on substrates used. Moreover, the inhibitory effect of C. prolifera extract on lipases appeared to be accelerated by adding bile salts, which likely modified the interface and allowed the inhibitory compound to inactivate the lipase. The separation of C. prolifera extract by thin-layer chromatography (TLC) resulted in eight fractions showing efficient inhibition rate against DGL, compared to the crude extract. In the case of HPL, TLC fractionation reduced the inhibitory rates, suggesting that the effect of algal extract on lipases may be caused by a synergetic action of several compounds within the extract. High-performance liquid chromatograph separation resulted in isolation of a major compound displaying high inhibition capacity of HPL activity. Caulerpa prolifera extract may therefore be useful in developing antiobesity drugs.


Assuntos
Eucariotos/química , Suco Gástrico/química , Suco Gástrico/enzimologia , Lipase/antagonistas & inibidores , Suco Pancreático/química , Suco Pancreático/enzimologia , Animais , Cães , Oceanos e Mares , Tunísia
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