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1.
BMC Public Health ; 21(1): 1866, 2021 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-34654404

RESUMO

BACKGROUND: New Nutri-Grade labelling, aimed at reducing Singaporeans' sugar consumption will be implemented for all pre-packaged non-alcoholic beverages (NABs) sold in retail outlets from end 2021 onwards. It is expected such labelling will have a major impact on sugar content of beverages, as well as the replacement of sugar with non-caloric alternatives. METHODS: This study used product label data obtained from in-store surveys to investigate sugar and sweetener composition of NABs present on the Singapore market. Using this data we calculated products prospective Nutri-Grade classification in order to compare the current market composition with relation to sugar and/or sweetener use. RESULTS: Over half of the NABs on market were sweetened with sugar (59%) and were associated with less healthy Nutri-Grades of 'C' and 'D'. The use of natural sweeteners; Stevia and Monk fruit, remains low (6%). CONCLUSION: With continuous efforts by the government in promoting public health nutrition, it is expected that there will be a greater usage of sugar substitutes among NABs in response to the upcoming implementation of Nutri-Grade and ever-fluctuating consumers' demands. The data collected in this study provide a point estimate (July-September 2020) on market composition and use of both sugar and artificial sweeteners in beverages prior to integration of the mandatory labelling requirements.


Assuntos
Bebidas , Edulcorantes , Bebidas/análise , Humanos , Estudos Prospectivos , Singapura , Açúcares , Edulcorantes/análise
2.
Regul Toxicol Pharmacol ; 95: 227-235, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29580972

RESUMO

A previously published fragmentation method for making reliable negative in silico predictions has been applied to the problem of predicting skin sensitisation in humans, making use of a dataset of over 2750 chemicals with publicly available skin sensitisation data from 18 in vivo assays. An assay hierarchy was designed to enable the classification of chemicals within this dataset as either sensitisers or non-sensitisers where data from more than one in vivo test was available. The negative prediction approach was validated internally, using a 5-fold cross-validation, and externally, against a proprietary dataset of approximately 1000 chemicals with in vivo reference data shared by members of the pharmaceutical, nutritional, and personal care industries. The negative predictivity for this proprietary dataset was high in all cases (>75%), and the model was also able to identify structural features that resulted in a lower accuracy or a higher uncertainty in the negative prediction, termed misclassified and unclassified features respectively. These features could serve as an aid for further expert assessment of the negative in silico prediction.


Assuntos
Dermatite Alérgica de Contato , Haptenos , Medição de Risco/métodos , Animais , Simulação por Computador , Bases de Dados Factuais , Cobaias , Humanos , Camundongos
4.
J Appl Toxicol ; 37(8): 985-995, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28244128

RESUMO

Dermal contact with chemicals may lead to an inflammatory reaction known as allergic contact dermatitis. Consequently, it is important to assess new and existing chemicals for their skin sensitizing potential and to mitigate exposure accordingly. There is an urgent need to develop quantitative non-animal methods to better predict the potency of potential sensitizers, driven largely by European Union (EU) Regulation 1223/2009, which forbids the use of animal tests for cosmetic ingredients sold in the EU. A Nearest Neighbours in silico model was developed using an in-house dataset of 1096 murine local lymph node (LLNA) studies. The EC3 value (the effective concentration of the test substance producing a threefold increase in the stimulation index compared to controls) of a given chemical was predicted using the weighted average of EC3 values of up to 10 most similar compounds within the same mechanistic space (as defined by activating the same Derek skin sensitization alert). The model was validated using previously unseen internal (n = 45) and external (n = 103) data and accuracy of predictions assessed using a threefold error, fivefold error, European Centre for Ecotoxicology and Toxicology of Chemicals (ECETOC) and Globally Harmonized System of Classification and Labelling of Chemicals (GHS) classifications. In particular, the model predicts the GHS skin sensitization category of compounds well, predicting 64% of chemicals in an external test set within the correct category. Of the remaining chemicals in the previously unseen dataset, 25% were over-predicted (GHS 1A predicted: GHS 1B experimentally) and 11% were under-predicted (GHS 1B predicted: GHS 1A experimentally). Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Dermatite Alérgica de Contato/etiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Modelos Biológicos , Preparações Farmacêuticas/química , Alternativas ao Uso de Animais , Animais , Simulação por Computador , Conjuntos de Dados como Assunto , Ensaio Local de Linfonodo , Camundongos , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Relação Estrutura-Atividade
5.
Nutrients ; 15(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36615901

RESUMO

The consumption of sugar and non-nutritive sweeteners has been associated with poor health outcomes. The aim of this paper was to provide a comparison of the range of sweetened or flavoured beverages between two high-income countries in the Asia-Pacific region: Australia and Singapore. Following the FoodTrackTM methodology, nutrition, labelling, and price data were collected from major Australian and Singaporean supermarket chains and convenience stores. The nutrient profiles of products were tested for differences using Kruskal−Wallis and Mann−Whitney U tests. The greatest number of products collected in Australia were from the 'carbonated beverages' category (n = 215, 40%), and in Singapore the greatest number of products were from the 'tea and coffee ready-to-drink' category (n = 182, 35%). There were more calorically sweetened beverages in Singapore compared with Australia (n = 462/517 vs. n = 374/531, p < 0.001). For calorically sweetened products, the median energy of Singaporean products was significantly higher than Australian products (134 kJ vs. 120 kJ per 100 mL, p = 0.009). In Australia, 52% of sweetened or flavoured beverages displayed a front-of-pack nutrient signposting logo, compared with 34% of sweetened or flavoured beverages in Singapore. These findings also indicate that the consumption of just one serving of calorically sweetened carbonated beverages or energy drinks would exceed the WHO maximum daily free sugar recommendations.


Assuntos
Bebidas , Bebidas Energéticas , Singapura , Austrália , Bebidas/análise , Bebidas Gaseificadas , Açúcares
6.
Food Res Int ; 173(Pt 2): 113475, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803798

RESUMO

Dairy and non-dairy (plant-based) alternatives are promoted as an essential component of a healthy diet. The purpose of this study was to evaluate the range of dairy milks and plant-based milk alternatives in supermarkets in Australia and Singapore, and to explore nutritional differences within the category, and between countries. Product information was collected in store from packaging. Products were sorted into dairy milks and plant-based milk alternatives, and further categorised as (i) breakfast drinks (12 % of products); (ii) plain milks (62 %); or (iii) flavoured milks (26 %). The nutrient profiles of products were tested for differences using Kruskal Wallis and Mann-Whitney U tests. Flavoured products contained almost double the median sugar content of plain products (8.3 g v. 4.6 g, p = 0.005). Two-thirds of the product range were dairy milks, which contained nearly four times the median saturated fat content (1.1 g v. 0.3 v, p < 0.0001) and more than double the amount of sugar (5.1 g v. 2.6 g, p < 0.0001) of plant-based milk alternatives, but three times more protein (3.3 g v. 1.0 g, p < 0.0001). Between countries, generally, calcium contents were similar across products, likely due to fortification of plant-based milk alternatives. Compared to Singapore, dairy milk and plant-based milk alternative products sold in Australia were generally higher in energy, protein and fat, but lower in carbohydrate content. Food supply differences between Singapore and Australia may be cultural and have nutritional implications.


Assuntos
Leite , Nutrientes , Animais , Estudos Transversais , Singapura , Valor Nutritivo , Açúcares
7.
Food Chem Toxicol ; 174: 113659, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36791904

RESUMO

Understanding trends in habits and practices of cosmetics and personal care products is essential for the assessment of product exposure and simultaneously, the establishment of safe use levels for incorporated ingredients. To date, most exposure data is limited to European and USA populations, with data on Asian-specific habits and practices lacking. This data gap needs to be filled as evidence has shown that there is a large variation in product use behaviors between consumers, across and within populations. Moreover, there is a need to seek a more efficient approach of data collection. Conventional methods of collecting habits and practices data require extensive effort and are generally cost and time intensive. In this publication, we demonstrate the feasibility of employing a rapid and cost-effective online survey approach to gather habits and practices for Southeast Asia, specifically Singapore. We describe the methodology and display the type of habits and practices data that can be gathered through this approach. Although certain limitations exist, this approach can be used to effectively collect preliminary product use data across regions and different product categories.


Assuntos
Qualidade de Produtos para o Consumidor , Cosméticos , Singapura , Inquéritos e Questionários , Hábitos
8.
Foods ; 11(18)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36140952

RESUMO

Commonly consumed foods and beverages can contain chemicals with reported carcinogenic activity in rodent models. Moreover, exposures to some of these substances have been associated with increased cancer risks in humans. Food-borne carcinogens span a range of chemical classes and can arise from natural or anthropogenic sources, as well as form endogenously. Important considerations include the mechanism(s) of action (MoA), their relevance to human biology, and the level of exposure in diet. The MoAs of carcinogens have been classified as either DNA-reactive (genotoxic), involving covalent reaction with nuclear DNA, or epigenetic, involving molecular and cellular effects other than DNA reactivity. Carcinogens are generally present in food at low levels, resulting in low daily intakes, although there are some exceptions. Carcinogens of the DNA-reactive type produce effects at lower dosages than epigenetic carcinogens. Several food-related DNA-reactive carcinogens, including aflatoxins, aristolochic acid, benzene, benzo[a]pyrene and ethylene oxide, are recognized by the International Agency for Research on Cancer (IARC) as causes of human cancer. Of the epigenetic type, the only carcinogen considered to be associated with increased cancer in humans, although not from low-level food exposure, is dioxin (TCDD). Thus, DNA-reactive carcinogens in food represent a much greater risk than epigenetic carcinogens.

9.
Curr Biol ; 17(7): 599-605, 2007 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-17363250

RESUMO

Reproductive behavior in Drosophila has both stereotyped and plastic components that are driven by age- and sex-specific chemical cues. Males who unsuccessfully court virgin females subsequently avoid females that are of the same age as the trainer. In contrast, males trained with mature mated females associate volatile appetitive and aversive pheromonal cues and learn to suppress courtship of all females. Here we show that the volatile aversive pheromone that leads to generalized learning with mated females is (Z)-11-octadecenyl acetate (cis-vaccenyl acetate, cVA). cVA is a major component of the male cuticular hydrocarbon profile, but it is not found on virgin females. During copulation, cVA is transferred to the female in ejaculate along with sperm and peptides that decrease her sexual receptivity. When males sense cVA (either synthetic or from mated female or male extracts) in the context of female pheromone, they develop a generalized suppression of courtship. The effects of cVA on initial courtship of virgin females can be blocked by expression of tetanus toxin in Or65a, but not Or67d neurons, demonstrating that the aversive effects of this pheromone are mediated by a specific class of olfactory neuron. These findings suggest that transfer of cVA to females during mating may be part of the male's strategy to suppress reproduction by competing males.


Assuntos
Drosophila/química , Drosophila/fisiologia , Ácidos Oleicos/fisiologia , Feromônios/fisiologia , Comportamento Sexual Animal/fisiologia , Acetatos , Animais , Corte , Proteínas de Drosophila/fisiologia , Feminino , Aprendizagem , Masculino , Receptores Odorantes/fisiologia , Olfato/fisiologia
10.
Curr Biol ; 15(3): 194-206, 2005 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-15694302

RESUMO

BACKGROUND: Associative memory formation requires that animals choose predictors for experiences they need to remember. When an artificial odor is paired with an aversive experience, that odor becomes the predictor. In more natural settings, however, animals can have multiple salient experiences that need to be remembered and prioritized. The mechanisms by which animals deal with multiple experiences are incompletely understood. RESULTS: Here we show that Drosophila males can be trained to discriminate between different types of female pheromones; they suppress courtship specifically to the type of female that was associated with unsuccessful courtship. Such "trainer-specific" learning is mediated by hydrocarbon olfactory cues and modifies the male's processing of those cues. Animals that are unable to use olfactory cues can still learn by using other sensory modalities, but memory in this case is not specific to the trainer female's maturation state. Concurrent and serial presentation of different pheromones demonstrates that the ability to consolidate memory of pheromonal cues can be modified by the temporal order in which they appear. CONCLUSION: Suppression of memory by new learning demonstrates that the dynamics of memory consolidation are subject to plasticity in Drosophila. This type of metaplasticity is essential for navigation of experience-rich natural environments.


Assuntos
Corte , Sinais (Psicologia) , Drosophila/fisiologia , Memória/fisiologia , Aprendizagem Seriada/fisiologia , Fatores Etários , Análise de Variância , Animais , Cromatografia Gasosa , Masculino , Odorantes , Reprodução/fisiologia , Atrativos Sexuais/química , Fatores de Tempo
11.
Food Chem Toxicol ; 120: 222-229, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30017998

RESUMO

ß-Myrcene is a flavoring substance that occurs naturally in a large variety of foods. At the request of the European Food Safety Authority (EFSA) for additional toxicological data on ß-myrcene, groups of Sprague Dawley rats (10/sex/group) were administered diets containing 0, 700, 2100, or 4200 ppm of ß-myrcene designed to provide nominal doses of 0, 50, 150, or 300 mg/kg bw/day in a 90-day GLP-compliant study. Based on body weights, feed consumption, and substance stability data, final estimated daily intakes of ß-myrcene were calculated to be 20.4, 58.8, and 115.2 mg/kg bw for males and 24.2, 70.0, and 135.9 mg/kg bw for females. No effects on clinical observations, hematology and clinical chemistry parameters, organ weights, or macroscopic and histopathological examinations were found attributable to ingestion of ß-myrcene. The oral no-observed-adverse-effect level (NOAEL) for rats of both sexes was the highest dose tested. Based on feed consumption and test substance stability in the diet, the NOAEL was calculated to be 115 and 136 mg/kg bw/day for males and females, respectively.


Assuntos
Exposição Dietética , Fidelidade a Diretrizes , Rim/efeitos dos fármacos , Monoterpenos/toxicidade , Monoterpenos Acíclicos , Ração Animal , Animais , Peso Corporal/efeitos dos fármacos , Testes de Carcinogenicidade , Cromatografia Gasosa , Relação Dose-Resposta a Droga , Comportamento Alimentar/efeitos dos fármacos , Feminino , Masculino , Monoterpenos/administração & dosagem , Nível de Efeito Adverso não Observado , Tamanho do Órgão/efeitos dos fármacos , Ratos Sprague-Dawley , Testes de Toxicidade Subcrônica
12.
Food Chem Toxicol ; 120: 544-551, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30075317

RESUMO

Methyl propyl trisulfide is a flavoring substance found in foods such as garlic and onions. At the request of the European Food Safety Authority (EFSA) for additional toxicological data on methyl propyl trisulfide, groups of Sprague-Dawley rats (10/sex/group) were gavaged with 0 (corn oil vehicle control), 0.5, 2, or 6 mg methyl propyl trisulfide/kg bw/day in a 90-day GLP-compliant study. No effects on clinical observations, hematology and clinical chemistry parameters, organ weights, or macroscopic and histopathological examinations were found attributable to ingestion of methyl propyl trisulfide. The oral no-observed-adverse-effect level (NOAEL) for rats of both sexes was the highest dose tested of 6 mg/kg bw/day.


Assuntos
Alcenos/efeitos adversos , Aromatizantes/efeitos adversos , Sulfetos/efeitos adversos , Administração Oral , Alcenos/administração & dosagem , Animais , Aromatizantes/administração & dosagem , Nível de Efeito Adverso não Observado , Ratos Sprague-Dawley , Sulfetos/administração & dosagem
13.
Food Chem Toxicol ; 120: 213-221, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29958989

RESUMO

Piperine (E,E-) is a naturally occurring pungent and spicy constituent of black pepperand is also used as an added flavoring ingredient to foods and beverages. Piperine has been determined safe under conditions of intended use as a flavoring substance by regulatory and scientific expert bodies. While concurring with the Joint FAO/WHO Expert Committee on Food Additives (JECFA) and Flavor and Extract Manufacturers Association (FEMA) Expert Panel on the safety of piperine, the European Food Safety Authority (EFSA) requested additional toxicological data. The results of a 90-day GLPcompliant dietary study, conducted in Sprague-Dawley rats at target doses of 0, 5, 15, or 50 mg/kg bw/day, to respond to this request are presented herein. No adverse effects were found attributable to ingestion of piperine. Statistically significant changes in food consumption, body weight gain, and plasma cholesterol levels were not considered adverse as discussed in this paper. Therefore, the oral no-observed-adverse-effect level (NOAEL) was determined to be the highest dose tested of 50 mg/kg bw/day. EFSA derived a lower NOAEL of 5 mg/kg bw/day based on increased plasma cholesterol levels which still affords an adequate margin of safety of over 48,000 and concluded that piperine is not of safety concern.


Assuntos
Alcaloides/toxicidade , Benzodioxóis/toxicidade , Exposição Dietética , Piperidinas/toxicidade , Alcamidas Poli-Insaturadas/toxicidade , Animais , Colesterol/sangue , Relação Dose-Resposta a Droga , Comportamento Alimentar/efeitos dos fármacos , Feminino , Masculino , Nível de Efeito Adverso não Observado , Ratos , Ratos Sprague-Dawley , Aumento de Peso/efeitos dos fármacos
14.
Proc Biol Sci ; 270(1518): 929-33, 2003 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-12803907

RESUMO

In many species, older males are often preferred mates because they carry 'good' genes that account for their viability. How females discern a male's age is a matter of question. However, for animals that rely heavily on chemical communication there is some indication that an animal's age can be determined by its scent. To investigate whether there are changes in body odours with age, and if so their composition, mice were trained in a Y-maze to discriminate urine odours of donor mice of different ages: Adult (3-10 months old) and Aged (more than 17 months old). Trained mice could discriminate between these two age groups by odour alone. To determine the chemical basis for these discriminations, studies were performed using gas chromatography and mass spectrometry. These analyses demonstrated differences in the ratio of urinary volatiles with age. The most prominent differences involved significantly greater amounts of 2-phenylacetamide and significantly lower amounts of methylbutyric acids in Aged animals relative to Adult animals. Fractionating and manipulating the levels of these compounds in the urine demonstrated that the mice can distinguish age based on variation in amounts of these specific compounds in the combined urine.


Assuntos
Acetamidas/urina , Envelhecimento/fisiologia , Benzenoacetamidas , Butiratos/urina , Indóis/urina , Odorantes , Acetamidas/isolamento & purificação , Envelhecimento/urina , Animais , Butiratos/isolamento & purificação , Discriminação Psicológica , Feminino , Cromatografia Gasosa-Espectrometria de Massas/veterinária , Masculino , Aprendizagem em Labirinto , Camundongos , Camundongos Endogâmicos C57BL , Odorantes/análise , Volatilização
15.
J Chem Ecol ; 29(9): 2085-100, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14584677

RESUMO

When stressed or challenged by a predator, the Australian green tree frog, Litoria caerulea, emits a characteristic nutty odor from its parotoid glands. This study identifies the source of the odor as the cyclic amide 2-pyrrolidone (2-PyrO). In addition, we demonstrate the presence of 2-PyrO's straight chain form, gamma-aminobutyric acid or GABA, in the frog's glandular secretion and propose an odorant-precursor relationship. What role both compounds play in the frog's defensive strategy remains unknown. Prolonged exposure to the odor is shown to result in adverse effects that may be attributed to a GABAergic mechanism. It is our hypothesis, however, that the odor acts as an aposematic signal, indicating the toxicity of the frog's nonvolatile secretion.


Assuntos
Anuros/fisiologia , Odorantes , Glândula Parótida/metabolismo , Pirrolidinonas/química , Pirrolidinonas/isolamento & purificação , Comunicação Animal , Animais , Moduladores GABAérgicos/farmacologia , Comportamento Predatório , Volatilização
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