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1.
J Nutr Health Aging ; 22(8): 916-922, 2018.
Article in English | MEDLINE | ID: mdl-30272093

ABSTRACT

OBJECTIVE: Modified texture food (MTF), especially pureed is associated with a high prevalence of under-nutrition and weight loss among older adults in long term care (LTC); however, this may be confounded by other factors such as dependence in eating. This study examined if the prescription of MTF as compared to regular texture food is associated with malnutrition risk in residents of LTC homes when diverse relevant resident and home-level covariates are considered. DESIGN: Making the Most of Mealtimes (M3) is a cross-sectional multi-site study. SETTING: 32 LTC homes in four Canadian provinces. PARTICIPANTS: Regular (n= 337) and modified texture food consumers (minced n= 139; pureed n= 68). MEASUREMENTS: Malnutrition risk was determined using the Mini Nutritional Assessment short-form (MNA-SF) score. The use of MTFs, and resident and site characteristics were identified from health records, observations, and standardized assessments. Hierarchical linear regression analyses, accounting for clustering, were performed to determine if the prescription of MTFs is associated with malnutrition risk while controlling for important covariates, such as eating assistance. RESULTS: Prescription of minced food [F(1, 382)=5.01, p=0.03], as well as pureed food [F(1, 279)=4.95, p=0.03], were both significantly associated with malnutrition risk among residents. After adjusting for age and sex, other significant covariates were: use of oral nutritional supplements, eating challenges (e.g., spitting food out of mouth), poor oral health, and cognitive impairment. CONCLUSIONS: Prescription of minced or pureed foods was significantly associated with the risk of malnutrition among residents living in LTC facilities while adjusting for other covariates. Further work needs to consider improving the nutrient density and sensory appeal of MTFs and target modifiable covariates.


Subject(s)
Diet/statistics & numerical data , Long-Term Care , Malnutrition/epidemiology , Meals , Weight Loss , Aged , Aged, 80 and over , Canada/epidemiology , Cross-Sectional Studies , Female , Homes for the Aged , Humans , Male , Nutrition Assessment , Nutritional Status , Prevalence , Risk Factors
2.
Clin Otolaryngol ; 36(1): 30-6, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21414151

ABSTRACT

OBJECTIVES: Reduced range of hyoid and laryngeal movement is thought to contribute to aspiration risk and pharyngeal residues in dysphagia. Our aim was to determine the extent to which movements of the hyoid and larynx are correlated in the superior and anterior directions in swallowing, and whether movement range is predictive of penetration-aspiration or pharyngeal residue. DESIGN: Prospective, single-blind study of penetration-aspiration and pharyngeal residue with objective frame-by-frame measures of hyoid and laryngeal excursion from videofluoroscopy. SETTING: Tertiary hospital and rehabilitation teaching hospital. PARTICIPANTS: Twenty-eight participants referred for videofluoroscopy: 13 women, aged 57-77; 15 men, aged 54-70. Individuals with known neurodegenerative diseases or prior surgery to the neck were excluded. Each swallowed three boluses of 40% w/v thin liquid barium suspension. OUTCOMES: Two speech-language pathologists independently rated penetration-aspiration, vallecular and pyriform sinus residue. Cervical spine length, hyoid and laryngeal displacement were traced frame-by-frame. Predictive power was calculated. RESULTS: Cervical spine length was significantly greater in men. Hyoid displacement ranged from 34-63% of the C2-4 distance. Arytenoid displacement ranged from 18-66%, with significantly smaller anterior displacement in men. Positive hyoid-laryngeal movement correlations in both axes were the most common pattern observed. Participants with reduced displacement ranges (≤ first quartile) and with abnormal correlation patterns were more likely to display penetration-aspiration. Those with reduced anterior hyoid displacement and abnormal correlation patterns had a greater risk of post-swallow pharyngeal residues. CONCLUSIONS: It is difficult for clinicians to make on-line appraisals of the extent to which hyoid and laryngeal movement may be contributing to functional swallowing consequences during videofluoroscopy. This study suggests that it is most important for clinicians to discern whether reduced anterior displacement of these structures is contributing to a patient's swallowing impairment. Measures of structural displacement in thin liquid swallowing should be corrected for variations in participant height. Reductions in anterior hyoid and laryngeal movement below the first-quartile boundaries are statistically associated with increased risk for penetration-aspiration and post-swallow residues.


Subject(s)
Deglutition Disorders/etiology , Deglutition/physiology , Hyoid Bone/physiopathology , Larynx/physiopathology , Aged , Deglutition Disorders/diagnostic imaging , Deglutition Disorders/physiopathology , Female , Fluoroscopy , Follow-Up Studies , Humans , Hyoid Bone/diagnostic imaging , Larynx/diagnostic imaging , Male , Middle Aged , Prospective Studies , Single-Blind Method , Videotape Recording
3.
Folia Phoniatr Logop ; 63(1): 36-42, 2011.
Article in English | MEDLINE | ID: mdl-20689308

ABSTRACT

OBJECTIVE: The chin-down maneuver is commonly used in dysphagia management to facilitate greater airway protection. However, the literature suggests that variation in maneuver execution may threaten the effectiveness of the intervention. Our goal was to study variation in chin-down maneuver execution given a uniform instruction. METHODS: Sagittal view digital video recordings were acquired from 408 healthy adults who performed sequences of reiterated water swallows in head-neutral and chin-down positions. Head angle measurements were extracted from the recordings, using markers on goggles worn by 176 participants. RESULTS: We observed considerable variation in head angle in the head-neutral swallowing task, with a trend to greater flexion in participants over the age of 65. Male participants showed greater variation in head angle than females. Head flexion during the chin-down swallowing tasks averaged 19°, in the range reported to yield clinical benefit in radiographic studies. CONCLUSION: We conclude that a clear, uniform instruction is adequate to facilitate execution of the chin-down maneuver to a degree that is likely to be of clinical benefit. The variation in head angle observed in this study warrants further research, particularly regarding the relationship between anatomical cervical spine curvature and head angle influence on swallowing.


Subject(s)
Deglutition/physiology , Head Movements/physiology , Adult , Aged , Aged, 80 and over , Anthropometry , Cervical Vertebrae , Chin , Deglutition Disorders/physiopathology , Deglutition Disorders/therapy , Epiglottis , Female , Humans , Jaw , Male , Middle Aged , Posture , Reference Values , Young Adult
4.
Physiol Meas ; 31(6): 843-55, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20479519

ABSTRACT

Swallowing dysfunction, or dysphagia, is a serious condition that can result from any structural or neurological impairment (such as stroke, neurodegenerative disease or brain injury) that affects the swallowing mechanism. The gold-standard method of instrumental swallowing assessment is an x-ray examination known as the videofluoroscopic swallowing study, which involves radiation exposure. Consequently, there is interest in exploring the potential of less invasive methods, with lesser risks of biohazard, to accurately detect swallowing abnormalities. Accelerometry is one such technique, which measures the epidermal vibration signals on a patient's neck during swallowing. Determining the utility of accelerometry signals for detecting dysphagia requires an understanding of the physiological source of the vibrations that are measured on the neck during swallowing. The purpose of the current study was to determine the extent to which movement of the hyoid bone and larynx contributes to the vibration signal that is registered during swallowing accelerometry. This question was explored by mapping the movement trajectories of the hyoid bone and the arytenoid cartilages from lateral videofluoroscopy recordings collected during thin liquid swallowing, and comparing these trajectories to time-linked signals obtained from a dual-axis accelerometer placed on the neck, just anterior to the cricoid cartilage. Participants for this study included 43 adult patients referred for videofluoroscopic swallowing studies to characterize the nature and severity of suspected neurogenic dysphagia. A software program was created to allow frame-by-frame tracking of structural movement on the videofluoroscopy recordings. These movement data were then compared to the integrated acceleration data using multiple linear regressions. The results concur with previous studies, implicating hyolaryngeal excursion as the primary physiological source of swallowing accelerometry signals, with both the hyoid and the larynx contributing approximately equal amounts to the explained variance of the dependent variable, the integrated accelerometry signal.


Subject(s)
Deglutition/physiology , Hyoid Bone/physiology , Larynx/physiology , Movement , Adult , Cricoid Cartilage , Deglutition Disorders/physiopathology , Female , Humans , Hyoid Bone/physiopathology , Larynx/physiopathology , Male , Neck , Regression Analysis , Retrospective Studies , Software , Vibration
5.
Physiol Meas ; 29(9): 1105-20, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18756027

ABSTRACT

Single-axis swallowing accelerometry has shown potential as a non-invasive clinical swallowing assessment tool. Previous swallowing accelerometry research has focused exclusively on the anterior-posterior vibration detected on the surface of the neck. However, hyolaryngeal motion during pharyngeal swallowing occurs in both the anterior-posterior and superior-inferior directions, suggesting that dual-axis accelerometry may be worthy of investigation. With this motivation, the present paper provides a characterization of dual-axis swallowing accelerometry signals from healthy adults in the time and time-frequency domains. Time-domain analysis revealed that signals in the two axes exhibited different probability density functions, and minimal cross-correlation and mutual information. Time-frequency analysis highlighted inter-axis dissimilarities in the scalograms, pseudo-spectra and temporal evolution of low- and high-frequency content. Therefore, it was concluded that the two axes contain different information about swallowing and that the superior-inferior axis should be further investigated in future swallowing accelerometry studies.


Subject(s)
Deglutition Disorders/physiopathology , Deglutition/physiology , Adult , Diagnostic Techniques, Digestive System , Female , Humans , Male , Middle Aged
6.
Am Psychol ; 52(6): 613-29, 1997 Jun.
Article in English | MEDLINE | ID: mdl-9174398

ABSTRACT

A general theory of domain identification is used to describe achievement barriers still faced by women in advanced quantitative areas and by African Americans in school. The theory assumes that sustained school success requires identification with school and its subdomains; that societal pressures on these groups (e.g., economic disadvantage, gender roles) can frustrate this identification; and that in school domains where these groups are negatively stereotyped, those who have become domain identified face the further barrier of stereotype threat, the threat that others' judgments or their own actions will negatively stereotype them in the domain. Research shows that this threat dramatically depresses the standardized test performance of women and African Americans who are in the academic vanguard of their groups (offering a new interpretation of group differences in standardized test performance), that it causes disidentification with school, and that practices that reduce this threat can reduce these negative effects.


Subject(s)
Achievement , Black or African American/psychology , Intelligence , Psychological Theory , Social Identification , Stereotyping , Students/psychology , Women/psychology , Adolescent , Child , Female , Humans , Male
7.
Dysphagia ; 12(1): 43-50; discussion 51, 1997.
Article in English | MEDLINE | ID: mdl-8997832

ABSTRACT

A mealtime screening tool was administered to 349 residents of a home for the aged to determine the prevalence of mealtime difficulties including, but not limited to, dysphagia. Mealtime difficulties, as assessed during a single meal observation of each resident, were documented in 87% of these individuals. Though 68% exhibited signs of dysphagia, 46% had poor oral intake, 35% had positioning problems, and 40% exhibited challenging behaviors. An increased prevalence of mealtime difficulties was related to both the presence and degree of cognitive impairment. Oral intake was best among residents with severe cognitive impairment, many of whom received partial to total feeding assistance. In contrast, poor oral intake was associated with mild-moderate cognitive impairment, pointing to a need for more aggressive intervention with this group. The results clearly demonstrate that the prevalence of a wide range of eating-related problems far exceeds accepted estimates of dysphagia alone and support a multidisciplinary approach to mealtime interventions for the institutionalized elderly. Additionally, the magnitude of problems identified has implications for both resource and staff-training requirements in long-term care facilities.


Subject(s)
Deglutition Disorders/epidemiology , Feeding and Eating Disorders/epidemiology , Homes for the Aged , Aged , Aged, 80 and over , Attitude , Cognition Disorders/epidemiology , Cross-Sectional Studies , Dentures , Diet , Eating , Feeding Behavior , Feeding and Eating Disorders/rehabilitation , Female , Health Personnel/education , Health Resources , Humans , Long-Term Care , Male , Mental Disorders/epidemiology , Ontario/epidemiology , Patient Care Team , Posture , Prevalence , Workforce
8.
J Pers Soc Psychol ; 69(5): 797-811, 1995 Nov.
Article in English | MEDLINE | ID: mdl-7473032

ABSTRACT

Stereotype threat is being at risk of confirming, as self-characteristic, a negative stereotype about one's group. Studies 1 and 2 varied the stereotype vulnerability of Black participants taking a difficult verbal test by varying whether or not their performance was ostensibly diagnostic of ability, and thus, whether or not they were at risk of fulfilling the racial stereotype about their intellectual ability. Reflecting the pressure of this vulnerability, Blacks underperformed in relation to Whites in the ability-diagnostic condition but not in the nondiagnostic condition (with Scholastic Aptitude Tests controlled). Study 3 validated that ability-diagnosticity cognitively activated the racial stereotype in these participants and motivated them not to conform to it, or to be judged by it. Study 4 showed that mere salience of the stereotype could impair Blacks' performance even when the test was not ability diagnostic. The role of stereotype vulnerability in the standardized test performance of ability-stigmatized groups is discussed.


Subject(s)
Black or African American , Intelligence Tests , Stereotyping , Female , Humans , Male , Task Performance and Analysis
9.
J Pers Soc Psychol ; 64(6): 885-96, 1993 Jun.
Article in English | MEDLINE | ID: mdl-8326471

ABSTRACT

It was predicted that high self-esteem Ss (HSEs) would rationalize an esteem-threatening decision less than low self-esteem Ss (LSEs), because HSEs presumably had more favorable self-concepts with which to affirm, and thus repair, their overall sense of self-integrity. This prediction was supported in 2 experiments within the "free-choice" dissonance paradigm--one that manipulated self-esteem through personality feedback and the other that varied it through selection of HSEs and LSEs, but only when Ss were made to focus on their self-concepts. A 3rd experiment countered an alternative explanation of the results in terms of mood effects that may have accompanied the experimental manipulations. The results were discussed in terms of the following: (a) their support for a resources theory of individual differences in resilience to self-image threats--an extension of self-affirmation theory, (b) their implications for self-esteem functioning, and (c) their implications for the continuing debate over self-enhancement versus self-consistency motivation.


Subject(s)
Dissociative Disorders/psychology , Interpersonal Relations , Personality Development , Self Concept , Adaptation, Psychological , Adult , Feedback , Female , Humans , Male , Personality Inventory , Social Support
10.
J Pers Soc Psychol ; 62(1): 26-37, 1992 Jan.
Article in English | MEDLINE | ID: mdl-1538314

ABSTRACT

Three experiments tested the idea that a motive to protect self-esteem (SE) from the threat of regret can influence decision making. Threat to SE was manipulated by varying whether people expected to know the outcome of their decisions. Study 1 showed that when Ss expected feedback about their decisions, only Ss low in SE made regret-minimizing choices. Study 2 showed that when Ss did not expect to know the outcome of their decisions, SE differences in choice strategies disappeared. Study 3 manipulated expectations about feedback on chosen and unchosen alternatives and showed that the more feedback that was expected, the more likely low but not high SE Ss were to make regret-minimizing choices. These studies suggest that people base decisions not only on objective attributes of choice alternatives, but also on the damage to SE that is perceived to result from a poor-decision outcome.


Subject(s)
Decision Making , Defense Mechanisms , Risk-Taking , Self Concept , Adult , Female , Gambling/psychology , Humans , Knowledge of Results, Psychological , Male , Personality Inventory
11.
Am Psychol ; 45(8): 921-33, 1990 Aug.
Article in English | MEDLINE | ID: mdl-2221564

ABSTRACT

This article explains how alcohol makes social responses more extreme, enhances important self-evaluations, and relieves anxiety and depression, effects that underlie both the social destructiveness of alcohol and the reinforcing effects that make it an addictive substance. The theories are based on alcohol's impairment of perception and thought--the myopia it causes--rather than on the ability of alcohol's pharmacology to directly cause specific reactions or on expectations associated with alcohol's use. Three conclusions are offered (a) Alcohol makes social behaviors more extreme by blocking a form of response conflict. (b) The same process can inflate self-evaluations. (c) Alcohol myopia, in combination with distracting activity, can reliably reduce anxiety and depression in all drinkers by making it difficult to allocate attention to the thoughts that provoke these states. These theories are discussed in terms of their significance for the prevention and treatment of alcohol abuse.


Subject(s)
Alcohol Drinking/psychology , Alcoholism/psychology , Social Behavior , Alcoholic Intoxication/psychology , Humans , Social Environment
12.
J Abnorm Psychol ; 99(2): 115-26, 1990 May.
Article in English | MEDLINE | ID: mdl-2348005

ABSTRACT

Two studies provided evidence that alcohol's relationship to psychological stress is indirect and is mediated by the allocation of attention. Study 1 found that, as the attentional demands of a distracting activity increased, so did alcohol's reduction of anxiety. Study 2 replicated this effect and found that a highly demanding activity could reduce anxiety even without alcohol. This study further implicated the role of attention in anxiety reduction by demonstrating a relationship between changes in anxiety and response latency to a secondary monitoring task. Finally, in both experiments, intoxicated subjects who did not perform any activity showed an increase in anxiety. From these data, we argue that alcohol affects psychological stress, to an important degree, through its ability, in conjunction with ongoing activity, to affect the amount of attention paid to stressful thoughts.


Subject(s)
Alcoholic Intoxication/psychology , Alcoholism/psychology , Attention/drug effects , Stress, Psychological/complications , Adaptation, Psychological/drug effects , Adult , Anxiety/psychology , Arousal/drug effects , Female , Humans , Male
13.
Addict Behav ; 15(5): 491-6, 1990.
Article in English | MEDLINE | ID: mdl-2248124

ABSTRACT

Intentional self-restraint may play an important role in the control of potentially addictive behavior. Unfortunately, for some individuals, efforts to reduce substance use may prove not only temporary but to increase the likelihood of a later "binge." An experimental study examined the relationship between prior self-restraint efforts and drinking. Results indicated that successfully restrained drinkers (i.e., those individuals who reported exerting considerable effort toward drinking self-control, and who were normatively successful, that is, light drinkers) responded to the sudden availability of alcohol with increased levels of consumption, relative to unrestrained drinkers at a similar level of habitual drinking. There was no such effect among unsuccessfully restraining (i.e., heavy) drinkers. These results suggest that a period of successful drinking restraint which is initiated by the individual, may lead to heightened subsequent alcohol consumption.


Subject(s)
Alcohol Drinking/psychology , Alcoholic Intoxication/psychology , Internal-External Control , Adult , Affect , Alcoholism/psychology , Cues , Female , Humans , Male , Risk Factors , Self Concept , Social Environment , Taste
15.
Chem Biol Interact ; 59(2): 129-39, 1986 Sep.
Article in English | MEDLINE | ID: mdl-3021347

ABSTRACT

Male golden Syrian hamsters were maintained on ethanol-containing liquid diets for 4 weeks, corresponding to an average daily intake of 17 g/kg body wt. The p-hydroxylation of aniline was markedly enhanced by this treatment while minimal effects were seen in benzphetamine N-demethylase and ethoxyresorufin O-deethylase activities; there was no change in the microsomal levels of cytochromes P-450. Hepatic microsomal preparations from the ethanol-treated hamsters were more efficient than controls fed isocaloric diets in converting 2-aminofluorene, 4-aminobiphenyl, benzidine and 2-acetylaminofluorene into mutagens in the Salmonella mutagenicity test. The same treatment had no effect on the metabolic activation of 2-naphthylamine and even inhibited the mutagenicity of 2-aminoanthracene. No increase was seen in the activation of the two polycyclic aromatic hydrocarbons, benzo[a]pyrene and 3-methylcholanthrene to mutagens and an inhibitory effect was seen with the former. The ethanol-induced increase in the mutagenicity of 2-aminofluorene was inhibited by 2-butanol but not by the hydroxyl radical scavenger dimethylsulphoxide. It is concluded that chronic ethanol ingestion modulates the bioactivation of aromatic amines and amides to mutagens, the effect being substrate dependent. This effect of ethanol may be catalysed by unique form(s) of cytochrome P-450 whose synthesis is induced by such treatment.


Subject(s)
Amines/metabolism , Ethanol/pharmacology , Microsomes, Liver/drug effects , Mixed Function Oxygenases/analysis , Mutagens/metabolism , Animals , Biotransformation , Cricetinae , Hydroxides , Hydroxyl Radical , In Vitro Techniques , Male , Mesocricetus , Microsomes, Liver/enzymology
16.
Mutat Res ; 162(1): 41-6, 1986 Aug.
Article in English | MEDLINE | ID: mdl-3724776

ABSTRACT

Hepatic microsomal mixed-function oxidase activities were determined in rats pretreated with the aromatic amines 2-aminoanthracene, 2-naphthylamine or 4-aminobiphenyl. All three amines stimulated the O-deethylation of ethoxyresorufin (cytochromes P-448) but none had any effect on the p-hydroxylation of aniline. 2-Aminoanthracene and 4-aminobiphenyl also stimulated the NADPH-dependent reduction of cytochrome c and 2-naphthylamine inhibited the N-demethylation of benzphetamine. Hepatic preparations from animals pretreated with 2-aminoanthracene were more efficient in converting this carcinogen to mutagens while in contrast pretreatment with Aroclor 1254 caused a marked decrease in mutagenicity. 4-Aminobiphenyl also enhanced its own activation but Aroclor-pretreated preparations were the most effective. The latter preparations were also more efficient than controls in activating 2-naphthylamine to mutagens. It is concluded that 4-aminobiphenyl and 2-aminoanthracene enhance their own activation at least partly, by inducing the synthesis of cytochromes P-448.


Subject(s)
Amines/metabolism , Microsomes, Liver/enzymology , Mixed Function Oxygenases/biosynthesis , Mutagens/metabolism , 2-Naphthylamine/metabolism , 2-Naphthylamine/toxicity , Amines/toxicity , Aminobiphenyl Compounds/metabolism , Aminobiphenyl Compounds/toxicity , Animals , Anthracenes/metabolism , Anthracenes/toxicity , Biotransformation , Enzyme Induction/drug effects , Male , Mutagenicity Tests , Rats , Rats, Inbred Strains
17.
Carcinogenesis ; 7(5): 825-9, 1986 May.
Article in English | MEDLINE | ID: mdl-3009048

ABSTRACT

Male Wistar albino rats were maintained on alcohol-containing liquid diets for 4 weeks. Hepatic post-mitochondrial preparations derived from these animals were more efficient than control in activating 4-aminobiphenyl and 2-aminofluorene to mutagens in the Ames test. The alcohol-induced enhancement in mutagenicity was not inhibited by dimethylsulphoxide indicating that the generation of hydroxyl radicals is not involved. The activation of 2-naphthylamine was not affected by the treatment with alcohol but the mutagenicities of 2-aminoanthracene, benzo[a]pyrene and 3-methylcholanthrene were inhibited. The same treatment markedly increased hepatic microsomal aniline p-hydroxylase and ethoxyresorufin O-de-ethylase activities and to a lesser extent benzphetamine N-demethylase and microsomal levels of total cytochromes P-450. It is concluded that chronic alcohol administration to rats modulates the metabolic activation of pre-carcinogens to their reactive intermediates presumably by causing the redistribution of cytochrome P-450 isozymes.


Subject(s)
Amines/metabolism , Ethanol/toxicity , Mutagens/metabolism , Animals , Biotransformation , Carcinogens/metabolism , Cytochrome P-450 CYP1A2 , Cytochrome P-450 Enzyme System/biosynthesis , Cytochromes/biosynthesis , Hydroxides/metabolism , Hydroxyl Radical , Hydroxylation , Male , Mutagenicity Tests , Oxygenases/physiology , Rats , Rats, Inbred Strains
19.
Cancer Res ; 45(8): 3573-7, 1985 Aug.
Article in English | MEDLINE | ID: mdl-4016737

ABSTRACT

Addition of the plant phenolic flavonoid (+)-catechin to rat liver microsomes inhibited the mutagenicity of the aromatic amines 2-aminofluorene and 4-aminobiphenyl in the Ames test. Similarly, (+)-catechin decreased the mutagenicity of N-hydroxy-4-amino-biphenyl, the proximate carcinogen, but, in contrast, had no effect on the mutagenicity of other direct-acting carcinogens such as N-methyl-N'-nitro-N-nitrosoguanidine and 9-aminoacridine. In vitro addition of (+)-catechin gave rise to a dose-dependent inhibition of the cytochrome P-450-dependent benzphetamine N-demethylase and ethoxyresorufin O-deethylase activities. This was achieved by impairment of the electron flow from the reduced pyridine nucleotide to the cytochrome. However, administration of (+)-catechin to rats had no effect on the in vitro mixed-function oxidase activities. It is concluded that the (+)-catechin inhibits the mutagenicity of aromatic amines in the Ames test by interfering with their cytochrome P-450-dependent bioactivation and by direct interaction with the proximate carcinogen, but the former mechanism is unlikely to occur in vivo because the high doses of the flavonoid required are not achieved.


Subject(s)
Amines/antagonists & inhibitors , Benzopyrans/pharmacology , Catechin/pharmacology , Mutagens , Amines/toxicity , Aminobiphenyl Compounds/antagonists & inhibitors , Aminobiphenyl Compounds/toxicity , Animals , Dose-Response Relationship, Drug , Fluorenes/antagonists & inhibitors , Fluorenes/toxicity , Male , Mixed Function Oxygenases/antagonists & inhibitors , Mutagens/metabolism , Rats , Rats, Inbred Strains
20.
Appl Opt ; 24(4): 527, 1985 Feb 15.
Article in English | MEDLINE | ID: mdl-18216982
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