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Individuals perceive organic food as being healthier and containing fewer calories than conventional foods. We provide an alternative way to investigate this organic halo effect using a mirrored method to Choice Experiments applied to healthiness judgments. In an experimental study (N = 415), we examined whether healthiness judgments toward a 200 g cookie box are impacted by the organic label, nutrition information (fat and sugar levels), and price and determined the relative importance of these attributes. In particular, we assessed whether food with an organic label could contain more fat or sugar and yet be judged to be of equivalent healthiness to food without this label. We hoped to estimate the magnitude of any such effect. Moreover, we explored whether these effects were obtained when including a widely used system for labeling food healthiness, the Traffic Light System. Although participants' healthiness choices were mainly driven by the reported fat and sugar content, the organic label also influenced healthiness judgments. Participants showed an organic halo effect leading them to consider the organic cookie as healthy as a conventional one despite containing more fat and sugar. Specifically, they considered the organic cookie as equivalent in healthiness to a conventional one, although containing 14% more of the daily reference intake for sugar and 30% more for fat. These effects did not change when including the Traffic Light System. This effect of the organic label could have implications for fat and sugar intake and consequent impacts on health outcomes., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Asking questions about a behavior has been found to influence subsequent performance of that behavior, a phenomenon termed the question-behavior effect (QBE). The present study addressed two under-researched questions concerning the QBE: (1) Can the QBE be used to change multiple health behaviors, and (2) does enhancing dissonance during questionnaire completion increase the magnitude of the QBE? Participants ( N  = 1534) were randomized to one of three conditions (dissonance-enhanced QBE; standard QBE; control) that targeted three health-protective behaviors (eating fruit and vegetables, physical activity, dental flossing) and three health-risk behaviors (alcohol intake, sedentariness, unhealthy snacking). The dissonance-enhanced intervention comprised a message designed to pressurize participants into forming healthful behavioral intentions. Behavior was assessed via self-reports at four-week follow up. Findings showed significant overall effects of the QBE both in increasing performance of health-protective behaviors ( p  = .001) and in reducing performance of health-risk behaviors ( p  = .04). Compared to the standard QBE condition, the dissonance-enhanced QBE intervention increased performance of health-protective behaviors ( p  = .04) and marginally reduced performance of health-risk behaviors ( p  = .07). The dissonance-enhanced QBE intervention outperformed the control condition in all analyses. This is the first report that a brief QBE intervention influences performance of multiple health behaviors. Findings supported the idea that magnifying dissonance increases the impact of the QBE.

The present research focused on water intake (WI) in young adults. Study 1 (N = 272) was a correlational study and showed affective attitude, perceived behavioural control, past behaviour and anticipated negative affective reactions (ANAR) to predict WI intentions. It also showed intentions, instrumental attitude, perceived behavioural control, and past behaviour to predict WI prospectively. In addition, ANAR moderates the relationship between intention and future water intake (WI). Study 2 (N = 197) was an experimental study and showed that daily text messages targeting ANAR plus a self-monitoring manipulation increased WI immediately after the intervention although this effect did not persist one month later. Mediation analysis indicated the intervention impacted WI via sequentially changing ANAR and intention., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

There is increasing evidence to suggest that work-family conflict is implicated in poor eating patterns. Yet, the underlying mechanism remains unexplored. The objectives of the present study were to demonstrate the interplay between work-family conflict, eating style, and unhealthy eating, and to test whether body mass index (BMI) and its interactions further explicate the relationships. In this study, 586 Malaysian adults (normal weight n = 437, overweight n = 149) completed a questionnaire, which included demographic variables, work-family scales, eating style measures, namely, restrained, emotional or external eating and reported food intake. As hypothesized, results showed that family-to-work conflict (FWC), emotional eating and external eating were positively related to unhealthy food consumption. In addition, emotional eating was found to moderate the impact of FCW on eating. These findings are consistent with research that has revealed emotional eating can indeed increase the positive association between stress such as conflict and unhealthy food choices. However, we found no clear support for the interactive effects of BMI. Our research builds on the findings of existing research as it demonstrates the role of eating style in explaining the association between work-family conflict and unhealthy eating. This conclusion has potential implications for appropriate interventions and calls for the enhancement of various policies to tackle obesity and other health problems., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

It is well established that stress is linked to changes in eating behaviors. Research using adult populations has shown that stress is associated with both increases and decreases in the amount and type of food consumed. However, due to a lack of research reviews, the relationship between stress and eating behaviors in children is unclear. This systematic research review and meta-analysis aimed to identify whether stress is associated with healthy and unhealthy eating behaviors in children aged 8-18 years. Studies were included in the review if they measured stress and included a measure of food consumption. All unique studies retrieved (N = 28,070) were assessed for their eligibility at title, abstract and full text levels. A total of 13 studies were included in the final review and data were analysed using Comprehensive Meta-Analysis. Using random-effects modelling, overall stress was not associated with a change in overall eating behaviors. However, additional analyses indicated stress was associated with unhealthy eating behaviors in both younger (Hedge's g = 0.283, p < 0.001) and older (Hedge's g = 0.274, p = 0.001) children. In contrast, stress was not associated with healthy eating behaviors in younger children (Hedge's g = 0.093, p = 0.156), but was negatively associated with healthy eating behaviors in older children (Hedge's g = -0.384, p < 0.001). The current findings are concerning as they suggest the impact of stress on unhealthy eating may begin as early as 8 or 9 years old. Future research ought to investigate further the role of psychological, behavioral and endocrine factors in the development of stress-related eating in children., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The present study aimed to extend the literature on text messaging interventions involved in promoting healthy eating behaviours. The theoretical framework was the Theory of Planned Behaviour (TPB). A randomized controlled trial was used to test the impact of daily text messages compared to no message (groups) for reducing processed meat consumption (PMC) over a 2 week period, testing the sequential mediation role of anticipated regret and intention on the relationship between groups and PMC reduction. PMC and TPB variables were assessed both at Time 1 and Time 2. Participants were Italian undergraduates (at Time 1 N = 124) randomly allocated to control and message condition groups. Undergraduates in the message condition group received a daily SMS, which focused on anticipated regret and urged them to self-monitor PMC. Participants in the control group did not receive any message. Those who completed all measures at both time points were included in the analyses (N = 112). Findings showed that a daily messaging intervention, controlling for participants' past behaviour, reduced self-reported consumption of PMC. Mediation analyses indicated partial serial mediation via anticipated regret and intentions. The current study provided support for the efficacy of a daily messaging intervention targeting anticipated regret and encouraging self-monitoring in decreasing PMC. Outcomes showed the important mediating role of anticipated regret and intentions for reducing PMC., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

This research investigated whether the Theory of Planned Behavior (TPB) with the addition of self-identity could predict fruit and vegetable intake when controlling for past behavior. Previous research had demonstrated the efficacy of TPB to predict intention and behavior in relation to food choice and the additional power of self-identity, but had failed assess the effects of self-identity while controlling for past behavior. At baseline (N = 210) TPB components and past behavior in relation to fruit and vegetable consumption plus self-identity as a healthy eater were measured by questionnaire in a sample of university students. At time 1, 4 weeks later, self-reported fruit and vegetable consumption was measured. Structural Equation Modelling (SEM) indicated attitude, PBC and self-identity to be significant predictors of intention (subjective norm and past behavior were not significant). Intention, self-identity and past behavior were direct predictors of behavior. The current findings support the independent effect of self-identity as a healthy eater on both intentions and future behaviour when controlling for TPB variables and also past behavior. The discussion considers the importance of self-identity in changing intentions and behavior for behaviors such as fruit and vegetable consumption., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Objective. The Wnt/β-catenin pathway is known to regulate cellular proliferation and plays a role in chemoresistance. Niclosamide, an FDA approved salicyclamide derivative used for the treatment of tapeworm infections, targets the Wnt/β-catenin pathway. Therefore, the objective of this study was to investigate niclosamide as a potential therapeutic agent for ovarian cancer. Methods. Tumor cells isolated from 34 patients' ascites with primary ovarian cancer were treated with niclosamide (0.1 to 5 μM) ± carboplatin (5 to 150 μM). Cell viability was assessed using the ATP-lite assay. LRP6, Axin 2, Cyclin D1, survivin and cytosolic free β-catenin levels were determined using Western blot analysis. Tumorspheres were treated, and Wnt transcriptional activity was measured by the TOPflash reporter assay. ALDH and CD133 were analyzed by Flow cytometry and IHC. ALDH1A1 and LRP6 were analyzed by IHC in solid tumor and in ascites before and after treatment with niclosamide. Results. Combination treatment produced increased cytotoxicity compared to single agent treatment in 32/34 patient samples. Western blot analysis showed a decrease in Wnt/β-catenin pathway proteins and the expression of target genes. A significant reduction of Wnt/β-catenin signaling was confirmed by TOPflash assay. There was increased staining of ALDH1A1 and LRP6 in ascites compared to solid tumor which decreased after treatment. Conclusion. This study demonstrates that niclosamide is a potent Wnt/β-catenin inhibitor. Targeting the Wnt/β-catenin pathway led to decreased cellular proliferation and increased cell death. These findings warrant further research of this drug and other niclosamide analogs as a treatment option for ovarian cancer., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Objective: The aim of our study was to examine cross-sectional and longitudinal associations between cigarette smoking and alcohol drinking, in a representative sample of English pupils., Method: Data from 13,635 school pupils in the Longitudinal Study of Young People in England (LSYPE) on usage of cigarettes from 2004 (typical age 14) to 2006 (age 16) and alcohol from 2004 to 2007 (age 17), analyzed with latent growth curve models., Results: The weighted percentage of pupils drinking alcohol increased from 26% at age 14 to 71% by age 17, smoking from 12% to 27% by age 16. Pupils with lower socio-economic status were more likely to smoke but less likely to drink alcohol regularly. Both behaviors were positively correlated at age 14, adjusted for several confounding factors. The rate of increase over time was also positively correlated., Conclusion: Cigarette smoking and alcohol drinking are already correlated by age 14, are socio-economically patterned, and 'move together' during adolescence. Future studies and interventions should be targeted at a younger age range, to identify early smoking and potentially hazardous alcohol drinking patterns., (Copyright © 2013 Elsevier Inc. All rights reserved.)

External eaters reportedly increase snack intake when stressed, which could be due to an attentional shift towards food stimuli. Attentional biases for food stimuli were tested in high and low external eaters in stress and control conditions, using a computerised Stroop. A significant interaction was observed between external eating group and condition for snack word bias. This suggested that low external eaters have a greater bias for snack words when unstressed and that stressed, high external eaters have a greater bias for snack words than stressed, low external eaters, which could contribute to stress-induced snack intake in high external eaters.

This study investigated schoolchildren's breakfast choices focusing on their reported usual intake and perceptions of fat-reduced or fibre-enriched alternatives. A total of 184 eleven- to fifteen-year-old were asked to participate, and 181 completed the study. Using pictures of food items, the children were instructed to reproduce their usual breakfast, and then breakfasts that would be: healthy, tasty, consumed by their parents, or approved by their parents. Participants' usual breakfast included breads and breakfast cereals containing a higher fibre content than that of the breakfast reported as most palatable. Their usual breakfast also contained products with less fibre than was the case for their healthy or perceived parental norm breakfasts. This may be interpreted as evidence that high-fibre bread and breakfast cereals are perceived as healthy but that consumption of these products is limited by palatability. In contrast to the ambivalence towards cereal products, corresponding disagreements between breakfasts were not observed for milk, and only a small systematic disagreement was observed for spread. Thus, the majority consumed the kind of milk and spread perceived as being healthy, tasty and parentally sanctioned despite the fact that full-fat products were frequently consumed. In conclusion, the results suggest that taste may be a barrier to consumption of high-fibre products, while consumption of low-fat products appears to be impeded by health beliefs.

This study investigated reported body weight, concerns about body weight and eating styles in habitual heavy users (consume>825 ml/day) and habitual non-users of artificially sweetened beverages (ASBs). Groups of habitual heavy users (N=51) and non-users (N=69) were compared on measures of weight using self-reported body mass index (BMI), and measures of weight concern and eating style using the Dutch Eating Behaviors Questionnaire (DEBQ), the Yale Eating Patterns Questionnaire (YEPQ), and the Eating Disorder Inventory (EDI). Habitual heavy users reported higher body weights (BMI), greater concerns about weight and greater tendencies toward certain eating styles, when compared to non-users. Using logistic regression, 82% of respondents were correctly classified as heavy or non-users of ASBs using body mass index and body-weight concerns. Associations between a heavy use of ASBs and certain eating styles can be explained by association with high body weights and concerns about body weight.

Objective: The objective of this study was to determine whether clinicopathologic findings or the immunohistochemical presence of molecular markers are predictive of clinical outcome in patients with small cell carcinoma of the cervix (SCCC)., Methods: A retrospective review of cases of carcinoma of the cervix was conducted to identify SCCC. From 1978 to 1999, 16 patients were identified at our institution with the diagnosis of SCCC. Microscopic sections of paraffin-embedded tissue specimens were evaluated for confirmation of diagnosis. Specimens were immunohistochemically stained with antibodies to three neuroendocrine markers: neuron-specific enolase, chromagranin (CGR), and synaptophysin. Specimens were also stained for protein expression of p53, erbB2, proliferating cell nuclear antigen, and c-myc. The relationship between molecular markers and clinical outcome was determined., Results: All 16 cases met the histologic criteria for SCCC. Fourteen of 16 tumors (88%) stained positive for neuroendocrine differentiation. Eleven of 16 patients (69%) died from disease with a median survival of 19 months; there were 3 long-term survivors (greater than 5 years). CGR was positive in 8 (50%) specimens and was found to be highly predictive of death (P = 0.001). Complete loss of p53 protein was seen in 8 patients, 7 of whom died with a median survival of 20 months., Conclusion: Immunohistochemistry can be helpful in confirming difficult cases of SCCC. Further studies are necessary to define molecular markers that may be predictive of outcome in patients with SCCC., (Copyright 2001 Academic Press.)

Vegetarianism within the U.K. is growing in popularity, with the current estimate of 7% of the population eating a vegetarian diet. This study examined differences between the attitudes and beliefs of four dietary groups (meat eaters, meat avoiders, vegetarians and vegans) and the extent to which attitudes influenced intentions to follow each diet. In addition, the role of attitudinal ambivalence as a moderator variable was examined. Completed questionnaires were obtained from 111 respondents (25 meat eaters, 26 meat avoiders, 34 vegetarians, 26 vegans). In general, predictions were supported, in that respondents displayed most positive attitudes and beliefs towards their own diets, and most negative attitudes and beliefs towards the diet most different form their own. Regression analyses showed that, as predicted by the Theory of Planned Behaviour, attitudes, subjective norm and perceived behavioural control were significant predictors of intention to follow each diet (apart from the vegetarian diet, where subjective norm was non-significant). In each case, attitudinal ambivalence was found to moderate the attitude-intention relationship, such that attitudes were found to be stronger predictors at lower levels of ambivalence. The results not only highlight the extent to which such alternative diets are an interesting focus for psychological research, but also lend further support to the argument that ambivalence in an important influence on attitude strength., (Copyright 2000 Academic Press.)

The present study examined the influences of attitudes, social norms, perceived control and underlying beliefs on 11 to 15-year-olds' breakfast choices of milk with different fat content and high-fibre bread. All pupils in the 5th, 7th and 9th grades in Mölndal community (N=1730), Sweden, were asked to complete a questionnaire based on the Theory of Planned Behaviour. Two weeks later, they were asked to fill in a 7-day record of food consumed for breakfast. Consumption of milk and high-fibre bread was predicted from intentions, and for milk also by perceived behavioural control. Intentions were influenced by attitudes, perceptions of significant others' preferences, and perceived control. In addition, perception of the parents' consumption (descriptive norm) of the specific food played an important role. Attitudes, norms and perceived control predicted intentions to a similar extent in each age group. Attitudes to the consumption of milk and high fibre bread were influenced by beliefs about their sensory and health aspects. Females and the oldest children had greater knowledge about the healthier alternatives and the oldest children had a tendency to choose healthier options., (Copyright 2000 Academic Press.)

The rabbit model of rotavirus infection has proved to be useful for assessing active immunity and protection after infection or vaccination with virus or virus-like particles. One limitation of the rabbit model is that after experimental infection of rabbits, clinical diarrhea is not routinely induced. Lack of diarrhea in the rabbit model has been proposed to be due to the fluid absorptive capability of the cecum or attenuation of virus strains through tissue culture adaptation. To test whether a wild-type lapine rotavirus strain BAP (BAPwt) isolated from diarrheic rabbits would cause disease on passage in rabbits, 1-, 2-, 10-, and 16-week-old rabbits were orally inoculated with BAPwt, its tissue culture-adapted counterpart strain (BAP-2), tissue culture-adapted lapine strain ALA, or PBS. Lapine rotavirus infection in 1-week-old, but not >/=2-week-old, rabbits resulted in the development of disease characterized by soft, wet, yellow-to-brownish-green partially formed-to-liquid stools observed only at the time of virus antigen shedding. The level and duration of virus shedding after infection were prolonged in 1-week-old rabbits compared with rabbits >/=2 weeks of age. Although diarrhea was not observed beyond the first 2 weeks of life, histopathological changes, including villus shortening and fusion, increased vacuolation of epithelial cells, and mononuclear infiltration of the lamina propria, were observed throughout the small intestine between 12 and 120 h after ALA infection in 1-week-old, 1- to 2-month-old, and 11-month-old rabbits. In 11-month-old rabbits, onset of intestinal damage appeared to be slightly delayed, was less severe, and was not observed in the duodenum. There were no differences in the immune responses to rotavirus infection in rabbits of different age groups (1 week to 5 years of age). All lapine rotavirus-inoculated rabbits seroconverted and were protected from virus challenge at 28 days postinoculation. Like in mice, rotavirus disease is age restricted in rabbits., (Copyright 1998 Academic Press.)

The presence of anti-Tax antibody responses in human T cell leukemia virus type I (HTLV-I)-infected individuals has been correlated with increased proviral load, increased risk of transmitting infection, and increased risk of developing tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM). In this study, a rabbit model of HTLV-I infection was used to determine whether anti-Tax antibody responses could predict the presence of virus with the potential to replicate. Seven of 14 HTLV-I-infected rabbits developed anti-Tax antibody responses. The onset of Tax reactivity was variable, but once detected remained constant throughout the remainder of the 60-week course of the study. All anti-Tax antibody positive rabbits produced virus as measured by p19 expression upon coculture, while p19 was detected in only one of the Tax antibody negative animals. Thus the presence of an anti-Tax antibody response correlates with p19 expression following cocultivation, and may be a useful predictor of virus replication in HTLV-I infected individuals., (Copyright 1998 Academic Press.)

Based on studies in animal models, parenteral immunization has become recognized as a potential vaccination strategy against rotavirus. Using an adult mouse model, the effects of the saponin adjuvant QS-21 on protection against murine rotavirus (strain EDIM) infection was determined following two intramuscular (i.m.) immunizations with purified EDIM particles including triple-layered (tl) infectious particles, tl particles inactivated with psoralen/UV, and double-layered (dl) inactivated particles. All three particles stimulated large serum rotavirus IgG responses and small amounts of serum rotavirus IgA, but undetectable stool rotavirus IgA. Inclusion of QS-21 during immunization increased the serum responses approximately 2- to 10-fold and also stimulated low levels of stool rotavirus IgA. Protection based on reduced shedding of rotavirus following EDIM challenge was significant (P < 0.001) with each immunized group and was enhanced (P < 0.001) by inclusion of QS-21 during immunization. Mice immunized with either live or inactivated tl particles and QS-21 were almost fully protected. Furthermore, animals inoculated with dl particles and the adjuvant shed significantly (P = .02) less virus following challenge than mice immunized with inactivated tl particles even though the latter induced measurable titers of neutralizing antibody to EDIM. These results demonstrate significant protection against rotavirus following i.m. immunization with both dl and tl EDIM particles which is consistently enhanced with QS-21.

A method utilizing pictures was used to assess food choice with 44 school boys in three different age groups (10, 13 and 16 years old). The aim of the study was to test reliability and construct validity (i.e. inter-instrument agreement) of food choice assessed when the boys were asked to compose breakfasts. The focus was on choices of milk, margarine, bread and breakfast cereals, as in these food groups it is possible to choose between low-fat/high-fat and low-fibre/high-fibre products. Subjects were asked to repeat their composing of breakfasts after eight weeks, and to complete a four-day food record on breakfasts after the second interview occasion. For comparisons between food choices a new non-parametric statistical method was used. Both reliability and construct validity were good for choices of milk and margarine. The unreliability could be explained as random in nature or in terms of healthier choices in the second interview., (Copyright 1998 Academic Press Limited.)

This paper reports a study of gender differences in the components of the Theory of Reasoned Action in relation to eating sweet snacks, and the role of these components in predicting sweet-snacking in women and men. Totals of 65 women and 64 men completed questionnaires assessing attitudes and behaviours towards eating sweet snacks. Women were more ambivalent towards eating sweet snacks than men, perceiving eating sweet snacks to be significantly less healthy (t(127) = - 2.43, p < 0.02), and more pleasant (t(127) = 2.52, p < 0.01). There were no statistically significant gender differences in outcome beliefs x evaluations, subjective norms, normative belief x motivation to comply, or in behavioural intention, although some gender differences were found within components. Women scored significantly higher (t(127) = 5.54, p < 0.0005) on restraint items from the Dutch Eating Behaviour Questionnaire, including those on snacking (t(127) = 5.04; p < 0.0005), but did not differ significantly from men on reported frequency of eating sweet snacks. There were gender differences in the predictive power of components of the Theory of Reasoned Action. Women's intentions to eat sweet snacks were predicted by perceived social pressure and attitudes towards sweet snacks. Men's intentions were only predicted significantly by attitudes. It is concluded that men's sweet-snacking is less influenced by social pressure than is women's.

We have evaluated the effect of colchicine, a potential antifibrotic drug, on bleomycin-induced pulmonary inflammation in hamsters. Pulmonary injury was induced by a single intratracheal (IT) instillation of bleomycin (bleo). Four groups of male Syrian hamsters each received one of four treatments: (1) IT bleo and twice daily intraperitoneal (IP) injections of colchicine (col) starting one day before IT instillation of bleo (bleo-col); (2) IT bleo and IP injections of saline (bleo-sal); (3) IT saline and IP colchicine (sal-col); and (4) IT saline and IP saline (sal-sal). Animals were sacrificed 28 days after IT treatment. Lung injury was evaluated histologically, biochemically and by analysis of bronchoalveolar lavage (BAL) fluid. Treatment of hamsters with colchicine did not ameliorate the bleo-induced lung injury, as determined by a semiquantitative morphological index that assesses the severity and extent of the lung injury on a scale of 0-3. Lung hydroxyproline measurements and BAL fluid cell count were also similar in bleo-col compared to bleo-sal hamsters. Colchicine did not prevent the bleo-induced restriction expressed by volume displacement. These results indicate that colchicine does not ameliorate the bleo-induced lung inflammation and fibrosis and call for further controlled investigations to justify the use of this drug in pulmonary disorders.

Relationship between body weight and the performance of five weight-related behaviours (limiting amount of food and drink at meals, avoid unnecessary fat, taking regular exercise, drinking little or no alcohol, avoiding calories in snacks) is examined in a sample of 165 normal-weight individuals. Each of these behaviours was commonly performed, particularly when trying to control body weight and shape. Avoiding alcohol, while being viewed as the least effective means of controlling weight, is found to be the only behaviour significantly related to lower current body weight. None of the five behaviours significantly correlate with amount lost in last effort to reduce weight. Self-reported intentions and previous performance of each behaviour are significantly predicted by components of the Theory of Planned Behaviour. The results are discussed in relation to implications for body weight and shape control and the prediction of behaviours and goal achievement.

In order to assess the relevance of the drug-nutrient interactions described in this chapter to routine toxicologic studies, the range of nutrient concentrations within which these interactions may occur must be compared to the range of nutrient concentrations found in routinely used rodent diets. While obviously deficient levels of some nutrients were supplied to demonstrate some of the interactions, others occur when the nutrients are present in adequate or excess levels, such as might be found in commercially available diets. These diets are known to vary from batch to batch in nutrient content. A lifetime toxicity/carcinogenicity bioassay using rodents may last longer than 2 years, during which time several batches of diet will be used. The variation in diet composition, coupled with inadequate diet description, makes nutrient-toxin interactions not only possible, but difficult to recognize. These considerations raise the practical and philosophical question as to what type of diet is most appropriate for rodents used for safety evaluation of drugs and chemicals. Is it appropriate to use diets that vary unpredictably in nutrient content, that infer a degree of protection against chemical carcinogenesis and which supply some nutrients such as protein in great excess of dietary needs? Is the increase in sensitivity to chemical carcinogens of animals fed purified diets desirable or does this increased sensitivity of the bioassay exceed that required to assess the risk of human exposure? In other words, is the use of purified diets likely to increase the number of false positive results? Proper interpretation and extrapolation of safety evaluation studies requires adequate description of the test system. Given the profound influence of diet on the response to some toxins, the composition of the diet should, ideally, be defined with the same rigor as are the test compound and the strain, age, sex, and housing conditions of the animals. It is likely, however, that natural ingredients diets will continue to be the diets of choice in safety evaluation studies. This is largely due to economic reasons. It is possible, however, to use these diets with greater confidence if open-formula diets are used and the concentration of each nutrient is reported. Consideration should also be given to preparing diets for use in adult and aging rodents, diets in which protein content is reduced.(ABSTRACT TRUNCATED AT 400 WORDS)

Horseradish peroxidase (HRP) absorption across the wall of the upper airway, monitored by the amount detected in the blood, is used to measure epithelial damage by toxins. Full details of kinetics of absorption and blood clearance have not been reported previously. We measured the kinetics under the experimental conditions used in testing toxins. HRP was administered to guinea pigs either by intraarterial injection of a 7.5 microgram bolus (plasma clearance) or by intratracheal instillation of 1 mg (respiratory tract absorption). Plasma concentrations were monitored for 60 min. Plasma concentrations of HRP rose linearly with time after intratracheal instillation, reaching 236 +/- 51 ng/ml (mean +/- SE) at 60 min after instillation. HRP was cleared from the plasma rapidly after bolus injection. The elimination coefficient, k2, determined from the biphasic log normal plot, was 0.322 min-1. These data were used to estimate the kinetics of absorption across the respiratory epithelium. A single 3-hr exposure to an atmosphere containing 2.5 mg/m3 of submicrometer zinc oxide particles increased plasma concentration of HRP after intratracheal deposition (407 +/- 63 ng/ml at 60 min) and had no effect on plasma clearance (k2 = 0.342 min-1). Therefore plasma concentrations of HRP measured after intratracheal deposition can be used as a sensitive indicator to evaluate the effects of inhalation of a test atmosphere on epithelial permeability, if plasma clearance kinetics are not altered by the exposure.

The ideal sugar concentration in a lime drink, the tolerance of deviations from that ideal, the choices between sweet and non-sweet foods, and tea and coffee sugaring habits, were assessed for each individual in an unstratified sample of 344 children and adults of both sexes, and body mass index (BMI) for 241 of them. Lime drink ideal point, hot-drink sugaring habits and the preferences for cake trolley over cheeseboard, flavoured milk shake over ice-cold milk, lemonade or tonic water over soda water and bread and margarine with honey or chocolate spread over plain bread and margarine, were all reliably associated positively with each other. This confirms the reality of the "sweet tooth", but not its extension to all sweet foods, because preferences for carrot over celery and for orange juice over tomato juice were not reliably associated with the other preferences. On average, the men showed a greater sweetness preference than the women. Women and younger subjects showed on average greater preferences for carrot and orange juice over the alternatives. When BMI was disconfounded from age and sex, it did not relate either to the preference for foods and drinks generally regarded as sweet or to the preference for a sweet alternative to a non-sweet vegetable food or drink.

Guinea pigs were exposed by nose only for 3 hr/day for 6 days to freshly formed zinc oxide (ZnO) particles (projected area diameter = 0.05 micron, sigma g = 2.0) at 5 mg/m3, the currently recommended threshold limit value (TLV). Ventilation, lung mechanics, lung volumes, and diffusing capacity for carbon monoxide (DLCO) in anesthetized, tracheostomized animals at 1, 24, 48, or 72 hr after the end of the last exposure were evaluated. At the same time intervals lung weight, lung fluid content, respiratory epithelial permeability to horseradish peroxidase, gross and microscopic appearance, and [3H]thymidine labeling of nuclei of bronchial and bronchiolar epithelial cells in other groups of animals were measured. Vital capacity, functional residual capacity, alveolar volume, and DLCO were all decreased following the last exposure and did not return to normal values by 72 hr. Increases in flow resistance and decreases in compliance and total lung capacity returned to normal by 72 hr. Lung weights were elevated due to inflammation involving the proximal portion of the alveolar ducts and adjacent alveoli. These changes were still present at 72 hr. [3H]Thymidine labeling of bronchiolar epithelial cell nuclei was increased for 48 hr. Respiratory epithelial permeability to horseradish peroxidase was not affected by the exposures. These results suggest that the current TLV for ZnO may not be adequate.

Lethality of anguidine (diacetoxyscirpenol) in rats and mice appears to be the result of primary or secondary cardiovascular collapse and to be related to severe tissue destruction in the gut and elsewhere. Experiments were performed in rats to examine the effect on anguidine lethality of treatment with several agents that alter gut function or toxic effects of other chemicals in the gut. Administration of atropine sulfate or methylatropine nitrate by sc injection to rats immediately following administration of an LD50 of anguidine and again 4 hr later gave modest but significant protection against anguidine lethality. The drugs were effective over a range of doses between 2.5 and 20 mg/kg, without a clear dose response, and probably were effective at doses lower than 2.5 mg/kg. S-Adenosylmethionine, 25 mg/kg, given to rats at the time of administration of an LD50 of anguidine and again 4 hr later gave some evidence of protection also. Semiquantitative evaluation of pathologic changes in the small intestine, a target of anguidine, indicated partial protection by atropine sulfate against anguidine toxicity at that site. Atropine-treated rats showed less severe damage, earlier resolution of damage, or both.

A characteristic of the trichothecene mycotoxin, anguidine, is its extreme toxicity to organs with populations of rapidly dividing cells. In preparation for evaluation of compounds that may protect against anguidine toxicity, we measured the LD50 of anguidine administered by gastric gavage (ig) or intraperitoneal injection (ip) and studied the dose- and time-dependent effects of anguidine on lymphohematopoietic organs, intestine, and testis, and measured hematocrit and peripheral blood leukocyte counts in male CD-1 mice. The ig LD50 at 96 hr was 15.5 mg/kg; after ip administration the LD50 at 96 hr was 20.0 mg/kg. Characteristic changes caused by sublethal doses of anguidine were cell depletion and necrosis in lymphohematopoietic organs, multifocal necrosis of intestinal epithelium, and diffuse necrosis of germinal epithelium followed by progressive tubule degeneration in the testes. There was leukocytosis due to both lymphocytosis and neutrophilia in the first few hours following anguidine exposure, followed by lymphopenia, neutropenia, and anemia by 3 days. After lethal doses, the intestinal necrosis was transmural, and there was extensive necrosis of lymphohematopoietic organs. There was rapid recovery after sublethal anguidine exposure of all anguidine-sensitive organs except for testis where decreased weights and abnormal spermatogenesis persisted for the 2-week observation period. Our results suggest that intestinal necrosis is an important cause of death following anguidine exposure. Atrophy of seminiferous tubules may have some value as an indicator of prior anguidine exposure, but the testicular changes are not unique to this compound.