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At least 883 records · Page 49Linked to original sources
PubMed2005

Contribution of enterococci to the spread of antibiotic resistance in the production chain of swine meat commodities.

Thirty-six samples, including fecal specimens, dry feedstuffs, raw and processed pork meat products, and dry fermented sausages, were collected from two production chains of swine meat commodities and analyzed for the presence of 11 antibiotic resistance (AR) genes. Specific PCR assays carried out on DNA extracted directly from the samples revealed a high incidence of the genes tet(K) (80.5%), ermB (66.7%), and tet(M) (66.7%). Feces and feedstuffs gave the largest number of positive amplifications. To elucidate the contribution of enterococci to the occurrence and spread of AR, 146 resistant enterococci were isolated, and their identity, genetic fingerprints, and AR gene profiles were determined by means of molecular techniques. Enterococcus faecalis and Enterococcus faecium were the predominant isolated species (43.8 and 38.4%, respectively); Other Enterococcus species identified were E. durans (8.9%), E. hirae (2.7%), E. gallinarum (2.1%), E. mundtii (2.1%), and E. casseliflavus (2.1%). A number of isolates displayed a complex AR gene profile comprising up to four different resistance determinants. The genes tet(M) and ermB were highly diffused, being present in 86.9 and 84.9%, respectively, of the isolates. The application of amplified fragment length polymorphism fingerprinting was particularly valuable to monitor the resistant enterococcal isolates along the production chain and to individuate steps in which contamination might occur. In fact, isolates of E. faecalis and E. faecium showing the same amplified fragment length polymorphism profile and AR gene pattern were detected in samples taken at different steps of the food chain suggesting three cases of bacterial clonal spread.

Animals↗
PubMed2005

Integrons in Escherichia coli from food-producing animals in The Netherlands.

The presence and character of class 1 integrons in multidrug-resistant Escherichia coli from slaughter animals and meat was determined by integrase-specific PCR and conserved segment PCR-restriction fragment length polymorphism (RFLP). At least five different class 1 integron types were found and three types were shared between hospitalized patients, humans in the community, meat, and slaughter animals. Common integron types indicate that antibiotic resistance genes are exchanged via the food chain between different reservoirs of both human and animal origin.

Animals↗
PubMed1984

Defenses against aflatoxin carcinogenesis in humans.

Aspects of work on aflatoxin mainly from the author's studies are discussed, emphasizing procedures, strategies and insights related to protection against aflatoxin carcinogenesis in man due to transmission in the food chain. Five lines of defense are discussed. First, is the interfacing of the farm animal as a biologic filter between contaminated crop (feed) and human food derived from animal products. Second, is chemical detoxification of meals with ammonia and of contaminated milk by ultraviolet light. Third is prevention of mold growth and aflatoxin elaboration with ammonium carbonate for potential application during storage and drying of agricultural products. Fourth, is the development of ultrasensitive analytical methods for aflatoxins with structural proof of identity. And, fifth are natural defenses related to the role of hydroxylation of mammalian metabolism in detoxification, especially the pathway to aflatoxin Q1, a major detoxifying mechanism in primates, and the epoxidation pathway and its relation to prevention of aflatoxin residue transmission into edible tissues.

Aflatoxins↗
PubMed2006

Bivalve molluscs as vectors of marine biotoxins involved in seafood poisoning.

Molluscs of many sorts, which are high in protein and trace minerals, have always been a substantial portion of the human diet. A great variety of mollusc species are therefore of commercial importance throughout the world. Episodes of poisoning occasionally happen to the consumers of molluscs, the main hazard being represented by bivalve molluscs. These organisms are filter-feeders, feeding mainly on a wide range of phytoplankton species. Among the thousands of species of microscopic algae at the base of the marine food chain, there are a few dozen which produce potent toxins. One major category of impact occurs when toxic phytoplankton are filtered from the water as food by shellfish, which then accumulate the algal toxins to levels which can be lethal to humans. Incidences of poisoning related to marine algal toxins come under the main categories of paralytic shellfish poisoning (PSP), neurotoxic shellfish poisoning (NSP), diarrhetic shellfish poisoning (DSP), and amnesic shellfish poisoning (ASP), depending upon the toxins and the symptoms that they cause. Since the beginning of the 1990s, a research program has been initiated to examine the toxin profiles in mussels from the Adriatic Sea. Since then, a number of polyether toxins have been isolated and characterized, some of which represent new additions to the DSP class of biotoxins. During this investigation, new types of toxins have also been isolated. The recent application of LC-MS methods for the detection of Adriatic marine biotoxins made it possible to speed up the analysis of toxic samples.

Animals↗
PubMed2006

Food-related advertising on preschool television: building brand recognition in young viewers.

OBJECTIVES: This study used content analysis to explore how much and what type of advertising is present in television programming aimed at toddlers and preschool-aged children and what methods of persuasion are being used to sell products and to promote brands to the youngest viewers. METHODS: Four randomly selected, 4-hour blocks (9 am to 1 pm) were recorded in spring 2005 from each of 3 stations airing programming aimed specifically at toddlers and preschool-aged children (Public Broadcasting Service, Disney, and Nickelodeon). All content that aired in the spaces between programs was examined. Data recorded for food-related advertisements included the primary appeals used to promote products or brands, whether advertisements were aimed at children or adults, whether advertisements used primarily animation or live action, whether advertisements showed food, and whether licensed characters were used. RESULTS: In 96 half-hour blocks of preschool programming, the 3 stations had a total of 130 food-related advertisements (1.354 food advertisements per half-hour). More than one half of all food advertisements (76 of 130 advertisements) were aimed specifically at children, and the majority of those were for fast food chains (50 advertisements) or sweetened cereals (18 advertisements). The primary advertising appeals used associated products with fun and happiness and/or with excitement and energy. Fast food advertisements in particular seemed to focus on building brand recognition and positive associations, through the use of licensed characters, logos, and slogans. CONCLUSIONS: The majority of child-oriented food advertisements viewed seemed to take a branding approach, focusing on creating lifelong customers rather than generating immediate sales. Promotional spots on advertisement-supported (Nickelodeon) and sponsor-supported (Public Broadcasting Service and Disney) networks took similar approaches and used similar appeals, seeming to promote the equation that food equals fun and happiness.

Advertising↗
PubMed2006

Assuring fish safety and quality in international fish trade.

International trade in fishery commodities reached US 58.2 billion dollars in 2002, a 5% improvement relative to 2000 and a 45% increase over 1992 levels. Within this global trade, developing countries registered a net trade surplus of US 17.4 billion dollars in 2002 and accounted for almost 50% by value and 55% of fish exports by volume. This globalization of fish trade, coupled with technological developments in food production, handling, processing and distribution, and the increasing awareness and demand of consumers for safe and high quality food have put food safety and quality assurance high in public awareness and a priority for many governments. Consequently, many countries have tightened food safety controls, imposing additional costs and requirements on imports. As early as 1980, there was an international drive towards adopting preventative HACCP-based safety and quality systems. More recently, there has been a growing awareness of the importance of an integrated, multidisciplinary approach to food safety and quality throughout the entire food chain. Implementation of this approach requires an enabling policy and regulatory environment at national and international levels with clearly defined rules and standards, establishment of appropriate food control systems and programmes at national and local levels, and provision of appropriate training and capacity building. This paper discusses the international framework for fish safety and quality, with particular emphasis on the United Nation's Food and Agricultural Organization's (FAO) strategy to promote international harmonization and capacity building.

Animals↗
PubMed1975

Total mercury in water, sediment, and selected aquatic organisms, Carson River, Nevada--1972.

A 1971-72 study of the Nevada Carson River drainage system by the Geological Survey, U.S. Department of Interior, revealed substantial amounts of mercury from pre-1900 gold and silver milling operations of the Comstock Lode. A monitoring survey was initiated to determine the extent of mercury uptake from corresponding surface water and sediments for seven aquatic species collected from five sampling stations along the watercourse. Total mercury content in fish ranged from 0.02 to 2.72 ppm; highest concentrations occurred in piscivorous white bass (0.50-2.72 ppm) sampled from Lahontan Reservoir. Residue levels appeared to be related to fish size, as demonstrated by highly significant correlations between wet weight and mercury content of five of the six species. Concentrations also appeared to be directly influenced by the species' position on the aquatic food chain. These results indicate that mercury levels in some fish from the Carson River drainage system may exceed the 0.50 ppm maximum concentration considered by the Food and Drug Administration, U.S. Department of Health, Education, and Welfare, to be safe for human consumption.

Animals↗
PubMed2001

[Ecotoxicology, human ecology, laser biotechnology in primary prevention of environmental health hazards].

Interdisciplinary studies in ecotoxicology (including the influence of complex physical, chemical and biological factors on ecosystems and human food chain), human ecology (related to estimation of individuals exposition to different pollutants both in the natural environment and in-door environment, as well as by food) and environmental biotechnology (based on application of high sensitive biological, especially embryological criteria in biotests for water quality, including image computisation and biosensors)--are scientific base for primary prevention of disturbances of the ecological balance as well as environmental risk factors for human health. Large scale applications of laser biostimulation in environmental engineering is a new chance for system approach in primary prevention by more efficient nutritional prevention, protection of proper water quality (including biotests) and protection of the human environment in working and living places.

Biotechnology↗
PubMed1985

IncH plasmids in Escherichia coli strains isolated from broiler chicken carcasses.

Plasmids conferring tellurite resistance were transferred at low temperature (27 degrees C) from Escherichia coli strains isolated from chicken carcasses at the time of slaughter and after storage. They belonged to group IncH, as evidenced by their large molecular weight and incompatibility with plasmid pIP233. E. coli strains contaminating chickens meat can thus represent a source of IncH plasmids in the food chain of humans.

Animals↗
PubMed1980

Nutritional implications of pesticides in foods.

Pesticides having a rapid and positive influence on the quantity of produced food, at the same time are involved in several side effects, often creating some hazard to human health and well-being. The authors show these facts in view of the possible entrance of these substances into the food chain, and present several actions or measures undertaken by various organizations, especially UN Agencies. The main emphasis is laid down on pesticides residues which remain in consumed food, based on the experience gained in different countries including Poland. From the toxicological or health point of view, it is important to know whether these substances interact with other nutrients entering plant or animal tissues or whether they remain on the surface, being easily removed before human consumption. Some effects of processing on decreasing the content of these residues in foodstuffs are also briefly outlined. Another aspect connected with the application of pesticides is their influence (mainly negative) on the nutritive value of harvested plants. In conclusion, the authors call for more attention and a complex approach in using pesticides for plant and animal protection as well as basic and applied nutrition, or health-oriented research along with training activity within national or rather international (e.g. UN Agency) programmes. They should be aimed at the optimal application of pesticides on modern agricultural practices with the main emphasis on their nutritional implication.

DDT↗
PubMed2003

Bovine spongiform encephalopathy.

Early epidemiological studies identified bovine spongiform encephalopathy as a feed-borne infection associated with infected meat-and-bone meal in animal feed. The infection may have derived from scrapie in sheep, a spontaneous genetic mutation in cattle, or a transmissible spongiform encephalopathy in another mammalian species. Experimental work on the risk of transmission has necessarily tried to identify risk materials and their infectivity levels, the nature and size of species barriers, the infectious dose, the route of infection, the strain of the agent and the genotype of the animals at risk. The identification of levels of infection in cattle tissues has aided the removal of risk materials from the human and animal food chains. Maternally associated transmission is unlikely to maintain an outbreak, but the offspring of clinical cases appear to be at greater risk when the rate of food-borne exposure is high. Studies of embryo transfer have not shown infection to be transmitted by this means. While the control measures appeared to be straightforward, compliance has at times proved difficult to enforce and quantify. This has necessitated more extensive prohibitions, aggressive enforcement and thorough auditing of compliance levels.

Animal Feed↗
PubMedDate not supplied

Campylobacter jejuni--an emerging foodborne pathogen.

Campylobacter jejuni is the most commonly reported bacterial cause of foodborne infection in the United States. Adding to the human and economic costs are chronic sequelae associated with C. jejuni infection--Guillian-Barré syndrome and reactive arthritis. In addition, an increasing proportion of human infections caused by C. jejuni are resistant to antimicrobial therapy. Mishandling of raw poultry and consumption of undercooked poultry are the major risk factors for human campylobacteriosis. Efforts to prevent human illness are needed throughout each link in the food chain.

Animals↗
PubMed1992

Arctic contaminants: sources, occurrence and pathways.

Potentially toxic organic compounds, acids, metals and radionuclides in the northern polar region are a matter of concern as it becomes evident that long-range transport of pollution on hemispheric to global scales is damaging this part of the world. In this review and assessment of sources, occurrence, history and pathways of these substances in the north, the state of knowledge of the transport media--the ocean and atmospheric circulation--is also examined. A five-compartment model of the northern region is developed with the intent of assessing the pathways of northern contaminants. It shows that we know most about pathways of acids, metals and radionuclides and least about those of complex synthetic organic compounds. Of the total annual inputs of anthropogenic acidic sulphur and the metals lead and cadmium to the Arctic via the atmosphere, an estimated 10-14% are deposited. A water mass budget for the surface layer of the Arctic Ocean, the most biologically active part of that sea, is constructed to examine the mass budget for one of the major persistent organochlorine compound groups found in remote regions, hexachlorocyclohexanes (HCH), one isomer of which is lindane. It is concluded that both the atmosphere and the ocean are important transport media. Even for the HCH substances which are relatively easily measured and simple in composition compared to other synthetic organics, we know little about the occurrence and environmental physical/chemical characteristics that determine pathways into the food chain. More environmental measurements, chemical characterization studies and environmental chemical transport modelling are needed, as is better knowledge of the circulation of the Arctic Ocean and the marine food web.

Acids↗
PubMed2004

Microbiological risk assessment models for partitioning and mixing during food handling.

To describe the transmission dynamics of a pathogen over a food pathway in quantitative microbiological risk assessment (QMRA), several types of processes need to be modelled. Next to microbial processes like bacterial growth and inactivation, four food handling processes can be identified. Among these are partitioning and mixing of the food product. With these processes, the (sizes of) units of food product are modified and the pathogenic cells are reallocated over the units, so that the prevalence of contaminated units and the number of cells per unit may change. Usually, simple models of these processes are applied in QMRA food chain models. These models assume independence of units, random homogeneous distribution of cells (for partitioning) and equal contribution of units (for mixing), which is often not realistic in food and food handling processes. In this paper, these assumptions are abandoned. The use of multivariate distributions is proposed to include the effect of dependence between units: the Multinomial distribution for partitioning and the Dirichlet distribution for mixing. Effects of cell clustering and/or unequal sizes of units formed by partitioning or contributing to mixing are incorporated. Some algorithms are derived that are easily implemented in spreadsheet models that simulate food production and preparation. Some examples show the effect of more realistic modelling by implementation of these algorithms on the prevalence and the probability distribution of the number of pathogens per unit of food product. In general, cell clustering will result in lower prevalences, but higher levels of contamination in contaminated food units. With the methods presented, these effects can be quantified. Difficulties in estimating the model parameters and the impact of implementation of the proposed methods on risk estimates in QMRA are discussed.

Bacteria↗
PubMed2004

[Are mycotoxins in food a health hazard?].

The effects of mycotoxins are well known since antiquity. Modern trace analysis show the wide prevalence of mycotoxins in the food chain. Aflatoxins (AFB1, AFB2, AFG1, AFG2), trichothecenes (deoxynivalenol, T-2 Toxin, HT-2 Toxin), zearalenone, fumonisins (FB1, FB2) and ochratoxin A are the most important mycotoxins world wide. Foods of plant origin are normally contaminated more frequently and in higher concentrations than food of animal origin. The mean concentrations of mycotoxins analysed in European foods can be assed as low. This may be one reason why acute poisonings are rare incidences and why the limits of the tolerable daily intake (TDI) levels are exceeded only very seldom; however the population group "infant" exceed the preliminary TDI-level for trichothecenes. The consequences of a chronic intake of low amounts of mykotoxins is hardly to assess. A participation of the aflatoxins in the pathogenesis of primary liver cancer is considered as certain. Other coherence between the dietary intake of mycotoxins and specific clinical symptoms of man are not convincingly shown till now.

Aflatoxins↗
PubMed2003

In vitro conjugal transfer of tetracycline resistance from Lactobacillus isolates to other Gram-positive bacteria.

The ability of 14 Lactobacillus strains, isolated from fermented dry sausages, to transfer tetracycline resistance encoded by tet(M) through conjugation was examined using filter mating experiments. Seven out of 14 tetracycline-resistant Lactobacillus isolates were able to transfer in vitro this resistance to Enterococcus faecalis at frequencies ranging from 10(-4) to 10(-6) transconjugants per recipient. Two of these strains could also transfer their resistance to Lactococcus lactis subsp. lactis, whereas no conjugal transfer to a Staphylococcus aureus recipient was found. These data suggest that meat lactobacilli might be reservoir organisms for acquired resistance genes that can be spread to other lactic acid bacteria. In order to assess the risk of this potential hazard, the magnitude of transfer along the food chain merits further research.

Animals↗
PubMed2002

Glucosinolates: bioavailability and importance to health.

Epidemiological studies suggest that brassica vegetables are protective against cancers of the lungs and alimentary tract. Cruciferous vegetables are the dietary source of glucosinolates, a large group of sulfur-containing glucosides. These compounds remain intact unless brought into contact with the enzyme myrosinase by pests, food processing, or chewing. Myrosinase releases glucose and breakdown products, including isothiocyanates. These highly reactive compounds are potent inducers of Phase II enzymes in vitro. Isothiocyanates also inhibit mitosis and stimulate apoptosis in human tumor cells, in vitro and in vivo. To understand and exploit such effects it is important to determine the routes of absorption of glucosinolate breakdown products, their metabolism, and delivery to systemic tissues. Glucosinolates can be gained or lost by vegetables during storage. They may be degraded or leached during processing, or preserved by thermal inactivation of myrosinase. Glucosinolates are broken down by plant myrosinase in the small intestine or by bacterial myrosinase in the colon. Isothiocyanates are absorbed from the small bowel and colon, and metabolites are detectable in human urine two to three hours after consumption of brassica vegetables. Interpretation of epidemiological data and exploitation of brassica vegetables for human health requires an understanding of glucosinolate chemistry and metabolism, across the whole food chain, from production and processing to the consumer.

Anticarcinogenic Agents↗
PubMed1993

[Control of salmonella infections in animal herds--basis for a reduction of salmonella entries into food].

Control measures against Salmonella infections in livestock are discussed on the basis of an epidemiological classification of Salmonella serovars important for animals and/or humans. Special attention is paid to immunoprophylaxis carried out additionally to generally accepted zoo sanitary measures. Available Salmonella vaccines are described and their major characteristics discussed briefly. Schemes are presented for the administration of vaccines in cattle, pigs and poultry. They have to be rationally integrated into general control concepts. They should serve as recommendations for the practical use in animal farms. It is concluded that given consequent combination and enforcement of the described measures the occurrence of Salmonella serovars important for animals and/or humans can be reduced decisively in livestock, thus minimizing introduction into the food chain for the sake of improved consumer protection.

Animals↗