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1.
Compr Rev Food Sci Food Saf ; 23(6): e70025, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39379291

RESUMO

Extensive monitoring programs of chemical hazards in the animal feed chain are in place, both organized by public and private organizations. The objective of this review was to prioritize chemical hazards for monitoring in the European animal feed supply chain. A step-wise approach was designed for the prioritization, based on: historical occurrence of the chemicals in animal feed ingredients and animal feeds (in relation to European guidance values or maximum limits in feed); information on transfer of the chemical to edible animal products, and; the extent of human dietary intake of the products and possible adverse human health effects of the chemical. Possible prioritization outcomes were: high (H), medium (M), or low (L) priority for monitoring, or classification not possible (NC) because of limited available data on the transfer of the chemical to edible animal tissues. The selection of chemicals included (with results in parentheses): dioxins and polychlorinated biphenyls (H); brominated flame retardants (H); per- and polyfluorinated alkyl substances (H); the heavy metals arsenic (H) and cadmium (H) as well as lead (M) and mercury (M); aflatoxins (H), ochratoxin A (NC), and other mycotoxins (L); pyrrolizidine alkaloids (H) and other plant toxins (NC); organochlorine pesticides (H) and other pesticides (L); pharmaceutically active substances (M); hormones (NC); polycyclic aromatic hydrocarbons (L), heat-induced processing contaminants (NC), and mineral oils (NC). Results of this study can be used to support risk-based monitoring by food safety authorities and feed-producing companies in Europe.


Assuntos
Ração Animal , Contaminação de Alimentos , Inocuidade dos Alimentos , Ração Animal/análise , Contaminação de Alimentos/análise , Europa (Continente) , Humanos , Animais , Retardadores de Chama/análise , Bifenilos Policlorados/análise , Dioxinas/análise , Metais Pesados/análise
2.
Compr Rev Food Sci Food Saf ; 23(5): e13403, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39137005

RESUMO

Foodborne illnesses result in a high disease burden worldwide, making food safety control of food business operations (FBOs) an urgent issue. With public agencies and FBOs facing challenges in monitoring the complex food supply chain with limited resources, scientific and objective insights into those factors that are related to food safety at FBOs are needed. These factors can be used as input for risk-based inspection. We conducted a systematic review to identify and analyze risk factors affecting the FBOs' food safety risk. We used a set of predefined search strings in Scopus and Web of Science to search for scientific manuscripts published in the English language between January 1 2003 and February 1 2023. The review identified 53 relevant studies and 43 risk factors. The presence of certified personnel turned out to be the most cited factor. Nearly half of the extracted factors had only been investigated in one study. Additional challenges were identified for developing a universal ready-to-use list of factors for the building of a risk-based inspection method, such as the limitation in the applicability of identified factors in different types of FBOs, and the variability in conclusions between publications for certain factors (e.g., FBO location and inspection history), stressing the need for additional research. Future studies should also prioritize standardizing definitions and measurements, particularly regarding compliance factors. In general, the current list of factors brought forward in our review lays the groundwork for building a transparent, objective, and risk-based method for food safety inspections of FBOs.


Assuntos
Inocuidade dos Alimentos , Doenças Transmitidas por Alimentos , Inocuidade dos Alimentos/métodos , Fatores de Risco , Humanos , Doenças Transmitidas por Alimentos/prevenção & controle , Inspeção de Alimentos/métodos , Inspeção de Alimentos/normas , Medição de Risco/métodos , Contaminação de Alimentos/prevenção & controle
3.
NPJ Sci Food ; 8(1): 36, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898076

RESUMO

In order to minimise food waste, side streams from feed and food production are increasingly being (re-) used in food supply chains. Such reuse contributes to the desire to implement circularity in food and agricultural systems. However, the reuse of side products in circular food systems may impact food safety, for instance, contaminant residues present at low levels in biomass may accumulate when reusing streams. In order to assess potential food safety issues related to circular food systems, a framework has been developed in this study. Based on this framework, appropriate actions can be taken to prevent from human health risks. The framework consists of three steps: 1. Describing the changes in the food supply chain as a result of the circularity transition; 2. Identifying potential food safety hazards related to the change; and 3. Prioritising food safety hazards related to the circularity transition. For the prioritisation, both the presence of the hazards in final foods and the effects of the hazards on human health need to be assessed. Persistence of the hazard in the environment and potential transfer from the environment to the final food product are relevant elements to include. The framework was tested in three case studies, showing that it allows for a prioritisation between hazards. Based on the case study results, circularity not so much influences the health effects of the hazards, but rather their presence depending on the persistence and transfer of food safety hazards in a circular system.

4.
Compr Rev Food Sci Food Saf ; 23(4): e13377, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38865251

RESUMO

Climate change and changing consumer demand are the main factors driving the protein transition. This shift toward more sustainable protein sources as alternatives to animal proteins is also reflected in the rapid upscaling of meat and dairy food analogues. Such changes could challenge food safety, as new food sources could result in new and unexpected food safety risks for consumers. This review analyzed the current knowledge on chemical and microbiological contamination of emerging alternative protein sources of plant origin, including soil-based (faba bean, mung bean, lentils, black gram, cowpea, quinoa, hemp, and leaf proteins) and aquatic-based (microalgae and duckweeds) proteins. Moreover, findings on commercial analogues from known alternative protein sources were included. Overall, the main focus of the investigations is on the European context. The review aimed to enable foresight approaches to food safety concerning the protein transition. The results indicated the occurrence of multiple chemical and microbiological hazards either in the raw materials that are the protein sources and eventually in the analogues. Moreover, current European legislation on maximum limits does not address most of the "contaminant-food" pairs identified, and no legislative framework has been developed for analogues. Results of this study provide stakeholders with a more comprehensive understanding of the chemical and microbiological safety of alternative protein sources and derived analogues to enable a holistic and safe approach to the protein transition.


Assuntos
Contaminação de Alimentos , Inocuidade dos Alimentos , Contaminação de Alimentos/prevenção & controle , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Proteínas de Plantas/química , Animais
5.
Food Res Int ; 168: 112791, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37120237

RESUMO

In this study, a methodology was developed that can be used as input for risk-based monitoring plans for chemical contaminants in food products. The novel methodology was applied to a case study in which cereals and fish were evaluated simultaneously for the possible presence of mycotoxins and heavy metals. The methodology was based on hazard quotients that were estimated by dividing the daily intake - using concentrations of the contaminants in the different food products and consumption of the respective products combined per product group - by the health based guidance value (HBGV) or reference points used for assessing potential health concerns (RPHC). The most relevant hazard-product combinations were further ranked based on the volume of import of the ingredients, per import country and a defined contaminant prevalence level per country. For fish, the hazard quotients were around ten times lower compared to the highest hazard quotients in cereals. Consumption of molluscs, mackerel-type fish and herring-type fish contaminated with mercury contributed most to the HBGV or RPHC. The top 25 hazard-product combinations for various age groups included: aflatoxin B1 in combination with wheat, rice (products), maize (products), and pasta, zearalenone in combination with wheat (products), T2/HT2-toxin in combination with rice (products), and DON in combination with wheat (products). The methodology presented showed to be useful in identifying the most relevant hazard-food-age group combinations and the most relevant import countries linked to these that should be included in the monitoring. As such, the method can help risk managers in establishing risk-based monitoring programs.


Assuntos
Micotoxinas , Zearalenona , Animais , Grão Comestível/química , Contaminação de Alimentos/análise , Micotoxinas/análise , Zearalenona/análise , Triticum
6.
Crit Rev Food Sci Nutr ; 63(30): 10319-10331, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35611891

RESUMO

Food production has increasingly become effective but not necessarily sustainable. Transitioning toward circular production systems aiming to minimize waste and reuse materials is one of the means to obtain a more sustainable food production system. However, such a circular food production system can also lead to the accumulation and recirculation of chemical hazards. A literature review was performed to identify potential chemical hazards related to the use of edible and non-edible resources in agriculture and horticulture, and edible plant and animal by-products in feed production. The review revealed that limited information was available on the chemical hazards that could occur when reusing crop residues in circular agriculture. Frequently mentioned hazards present in edible and non-edible resources are heavy metals, process and environmental contaminants, pesticides and pharmaceuticals. For feed, natural toxins and pharmaceutical residues are of potential concern. Studies, furthermore, indicated that plants are capable of taking up chemical hazards when grown on contaminated soil. The presence of chemical hazards in manure, sewage sludge, crop residues, and animal by-products may lead to accumulation in a circular food production system. Therefore, it is relevant to identify these hazards prior to application in food production and, if needed, take precautionary measures to prevent food safety risks.


Assuntos
Poluentes do Solo , Animais , Poluentes do Solo/análise , Agricultura , Esgotos/química , Inocuidade dos Alimentos , Plantas Comestíveis
7.
Crit Rev Food Sci Nutr ; 63(32): 11063-11080, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35757863

RESUMO

Traditionally, meat and dairy products have been important protein sources in the human diet. Consumers are eating more plant-based proteins, which is reflected in current market trends. Assessing how alternative proteins are processed and their impact on food safety helps realize market opportunities while ensuring food safety. In this review, an analysis of the food safety hazards, along with current industry trends and processing methods associated with alternative proteins for meat and dairy products for the European Union market is described. Understanding the effects of processing and safety alternative proteins is paramount to ensuring food safety and understanding the risks to consumers. However, the data here is limited. With the expected further increase in protein alternatives in consumers' diets, the risk of food allergens is apparent. The occurrence of processing contaminants in plant-based alternatives may occur, along with anti-nutritional compounds, which interfere with the absorption of nutrients. Further, typical food safety hazards related to the plant, the product itself, or processing are relevant. Although hazards in insects and seaweed are being addressed, other protein alternatives like cultured meat and SCPs warrant attention. Our findings can aid industry and governmental authorities in understanding current trends and prioritizing hazards for future monitoring.


Assuntos
Inocuidade dos Alimentos , Carne , Humanos , Carne/análise , Laticínios , União Europeia
8.
Food Res Int ; 158: 111505, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35840214

RESUMO

European food production systems have become very efficient in terms of high yield, quality and safety. However, these production systems are not sustainable since, amongst other reasons, a significant proportion of the production is wasted or lost in the supply chain. One of the strategies of the European Union is to achieve climate neutrality by moving towards a circular economy with better waste management. This includes, reducing food waste and losses, and reusing or recycling by-products of the food and feed production systems. A circular economy would greatly improve the sustainability of the European food systems, but attention must be paid to the emergence of (new) food safety hazards. New or not well-known hazards can occur because by-products are reintroduced into the system or new processing steps are used for recycling, and/or known hazards can accumulate in the food production chain due to the reuse of (by-)products. This review addresses food safety hazards in the circular biobased economy, covering the domains of plant production, animal production, aquaculture, and packaging. Instead of an exhaustive list of all potential hazards, example cases of circular food production systems are given, highlighting the known and potential emerging food safety hazards. Current literature covering emerging food safety hazards in the circular economy shows to be limited. Therefore, more research is needed to identify food safety hazards, to measure the accumulation and the distribution of such hazards in the food and feed production systems, and to develop control and mitigation strategies. We advocate a food safety by design approach.


Assuntos
Eliminação de Resíduos , Gerenciamento de Resíduos , Animais , Europa (Continente) , Alimentos , Inocuidade dos Alimentos
9.
J Food Sci ; 86(12): 5078-5086, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34796503

RESUMO

Risk-based monitoring programs are increasingly applied for cost-effective monitoring of food safety. Such programs ideally consist of three steps: risk-ranking, risk-based inspections, and cost-effective monitoring. Various methods have been described to perform the first step of risk-based monitoring. However, once the risk-ranking has been completed, identifying the hazard-food combinations to monitor, the frequency of inspection needs to be established based on a prioritization of food business operators (FBOs). The aim of this paper is to provide an overview of methods available for risk-based inspections. Literature shows that FBO's food safety compliance can be assessed based on company size, historical monitoring data, and socio-economic factors influencing compliance behavior. Non-compliance can either be intentional or unintentional. The latter can be assessed by evaluating the food safety culture of a company. Various models-ranging from qualitative (e.g., focus groups) to quantitative (e.g., scoring)-can be used for this purpose. These models usually include an evaluation of the organizational structure (e.g., management control, communication, commitment), the technical food safety environment (e.g., hygienic design, zoning), and employee characteristics (e.g., knowledge, risk awareness). Intentional non-compliance can be assessed using food fraud vulnerability tools. These tools incorporate factors influencing the likelihood of food fraud at the company, that is, opportunity, motivation, and (lack of) control measures. The literature indicates that either self-assessment tools or risk matrices are applied. There is no global consensus on the methods to apply for risk-based inspections. Depending on time and budget available as well as preferred output, one of the presented methods may be applied for prioritizing FBOs.


Assuntos
Inocuidade dos Alimentos , Alimentos , Grupos Focais , Fraude
10.
Crit Rev Food Sci Nutr ; 58(2): 178-193, 2018 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26857813

RESUMO

This study aimed to critically review methods for ranking risks related to food safety and dietary hazards on the basis of their anticipated human health impacts. A literature review was performed to identify and characterize methods for risk ranking from the fields of food, environmental science and socio-economic sciences. The review used a predefined search protocol, and covered the bibliographic databases Scopus, CAB Abstracts, Web of Sciences, and PubMed over the period 1993-2013. All references deemed relevant, on the basis of predefined evaluation criteria, were included in the review, and the risk ranking method characterized. The methods were then clustered-based on their characteristics-into eleven method categories. These categories included: risk assessment, comparative risk assessment, risk ratio method, scoring method, cost of illness, health adjusted life years (HALY), multi-criteria decision analysis, risk matrix, flow charts/decision trees, stated preference techniques and expert synthesis. Method categories were described by their characteristics, weaknesses and strengths, data resources, and fields of applications. It was concluded there is no single best method for risk ranking. The method to be used should be selected on the basis of risk manager/assessor requirements, data availability, and the characteristics of the method. Recommendations for future use and application are provided.


Assuntos
Inocuidade dos Alimentos , Doenças Transmitidas por Alimentos/epidemiologia , Medição de Risco/métodos , Efeitos Psicossociais da Doença , Técnicas de Apoio para a Decisão , Árvores de Decisões , Contaminação de Alimentos , Microbiologia de Alimentos , Doenças Transmitidas por Alimentos/microbiologia , Humanos , Anos de Vida Ajustados por Qualidade de Vida , Risco
11.
J Food Sci ; 82(2): 477-483, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28146273

RESUMO

In order to prevent food safety incidents from becoming a crisis, a good crisis management structure is essential. The aim of the current study was to compare and evaluate the national food incident response plans of 2 neighboring EU Member States: Germany and the Netherlands. This revealed that the structure of these plans is comparable, starting with initial alerting, assessment of the problem, upscaling, an execution phase and finally an evaluation of the crisis management. However, the German communication structure is more complex than the Dutch one and cross-border communication between both countries is currently limited. In general, the presence of national response plans does not guarantee a good and swift response to a food safety incident as this is often hampered by difficulties in tracing the source of the problem as well as difficulties in communication between organizations involved in crisis management. A timely detection can be improved through the development of fast screening and detecting systems and through combining various data sources using computer software systems. Mutual cooperation and communication can be improved through joint exercises or projects. This will help to streamline communication toward consumers and trade partners. Such communication should be transparent relaying not only the facts but also the uncertainties in a crisis in order to gain consumer trust and safeguard international trade.


Assuntos
Comunicação , Inocuidade dos Alimentos , Doenças Transmitidas por Alimentos/prevenção & controle , Planejamento em Desastres , Alimentos , Microbiologia de Alimentos , Alemanha , Órgãos Governamentais , Humanos , Países Baixos , Saúde Pública
12.
Compr Rev Food Sci Food Saf ; 16(1): 59-75, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33371550

RESUMO

Monitoring of dairy products should preferably focus on the most relevant food safety hazards in the dairy supply chain. For this purpose, the possible presence of microbiological, chemical, and physical hazards as well as trends in the dairy supply chain that may affect their presence were assessed. A literature review was combined with available data from EFSA, RASFF, and the Dutch monitoring program on chemical hazards as well as expert information. This study revealed that microbiological hazards are encountered more frequently in dairy products than chemical and physical hazards. Listeria monocytogenes, Staphylococcus aureus, Salmonella, and human pathogenic Escherichia coli were identified as the most important microbiological hazards in dairy products. Soft and semisoft cheeses are most frequently associated with L. monocytogenes and S. aureus enterotoxins, whereas raw milk is most frequently associated with human pathogenic E. coli and Campylobacter spp., Cronobacter spp., and Salmonella spp. are the microbiological hazards of most concern in powdered infant formula. Based on literature, monitoring, and RASFF data, the most relevant chemical hazards in dairy products are aflatoxin M1 , dioxins, and dioxin-like compounds and residues of veterinary drugs. Chemical hazards primarily occur at the dairy farm and may accumulate during further processing. The most relevant physical hazards are metal, glass, and plastic particles introduced during processing. Analysis of trends in the near future revealed that increased milk production is seen as most relevant in relation to food safety. Other trends affecting food safety are climate change and changes at the farm level, which aim to improve animal welfare and environmental sustainability.

13.
Physiol Res ; 65(2): 341-8, 2016 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-27322010

RESUMO

Electrophysiological studies of whole organ systems in vitro often require measurement of nerve activity and/or stimulation of the organ via the associated nerves. Currently two-compartment setups are used for such studies. These setups are complicated and require two fluids in two separate compartments and stretching the nerve across one chamber to the other, which may damage the nerves. We aimed at developing a simple single compartment setup by testing the electrophysiological properties of FC-770 (a perfluorocarbon) for in vitro recording of bladder afferent nerve activity and electrical stimulation of the bladder. Perflurocarbons are especially suitable for such a setup because of their high oxygen carrying capacity and insulating properties. In male Wistar rats, afferent nerve activity was recorded from postganglionic branches of the pelvic nerve in vitro, in situ and in vivo. The bladder was stimulated electrically via the efferent nerves. Organ viability was monitored by recording spontaneous contractions of the bladder. Additionally, histological examinations were done to test the effect of FC-770 on the bladder tissue. Afferent nerve activity was successfully recorded in a total of 11 rats. The bladders were stimulated electrically and high amplitude contractions were evoked. Histological examinations and monitoring of spontaneous contractions showed that FC-770 maintained organ viability and did not cause damage to the tissue. We have shown that FC-770 enables a simple, one compartment in vitro alternative for the generally used two compartment setups for whole organ electrophysiological studies.


Assuntos
Fluorocarbonos/farmacologia , Neurônios Aferentes/fisiologia , Bexiga Urinária/inervação , Bexiga Urinária/fisiologia , Animais , Estimulação Elétrica/métodos , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Fenômenos Eletrofisiológicos/fisiologia , Masculino , Neurônios Aferentes/efeitos dos fármacos , Ratos , Ratos Wistar , Bexiga Urinária/efeitos dos fármacos
14.
Psychophysiology ; 52(12): 1646-63, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26332849

RESUMO

When two different color stimuli are presented in rapid succession, the resulting percept is sometimes that of a mixture of both colors, due to a perceptual process called color fusion. Although color fusion might seem to occur very early in the visual pathway, and only happens across the briefest of stimulus presentation intervals (< 50 ms), the present study showed that spatial attention can alter the fusion process. In a series of experiments, spatial cues were presented that either validly indicated the location of a pair of (different) color stimuli in successive stimulus arrays, or did not, pointing toward isoluminant gray distractors in the other visual hemifield. Increased color fusion was observed for valid cues across a range of stimulus durations, at the expense of individual color reports. By contrast, perception of repeated, same-color stimulus pairs did not change, suggesting that the enhancement was specific to fusion, not color discrimination per se. Electrophysiological measures furthermore showed that the amplitude of the N1, N2pc, and P3 components of the ERP were differentially modulated during the perception of individual and fused colors, as a function of cueing and stimulus duration. Fusion itself, collapsed across cueing conditions, was reflected uniquely in N1 amplitude. Overall, the results suggest that spatial attention enhances color fusion and decreases competition between stimuli, constituting an adaptive slowdown in service of temporal integration.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Percepção de Cores/fisiologia , Potenciais Evocados Visuais/fisiologia , Percepção Espacial/fisiologia , Adolescente , Cor , Sinais (Psicologia) , Eletroencefalografia , Feminino , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação/fisiologia , Adulto Jovem
15.
Poult Sci ; 94(8): 1742-50, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26049800

RESUMO

Housing systems for laying hens have changed over the years due to increased public concern regarding animal welfare. In terms of sustainability, animal welfare is just one aspect that needs to be considered. Social aspects as well as environmental and economic factors need to be included as well. In this study, we assessed the sustainability of enriched cage, barn, free-range, and organic egg production systems following a predefined protocol. Indicators were selected within the social, environmental, and economic dimensions, after which parameter values and sustainability limits were set for the core indicators in order to quantify sustainability. Uncertainty in the parameter values as well as assigned weights and compensabilities of the indicators influenced the outcome of the sustainability assessment. Using equal weights for the indicators showed that, for the Dutch situation, enriched cage egg production was most sustainable, having the highest score on the environmental dimension, whereas free-range egg production gave the highest score in the social dimension (covering food safety, animal welfare, and human welfare). In the economic dimension both enriched cage egg and organic egg production had the highest sustainability score. When weights were attributed according to stakeholder outputs, individual differences were seen, but the overall scores were comparable to the sustainability scores based on equal weights. The provided method enabled a quantification of sustainability using input from stakeholders to include societal preferences in the overall assessment. Allowing for different weights and compensabilities helps policymakers in communicating with stakeholders involved and provides a weighted decision regarding future housing systems for laying hens.


Assuntos
Criação de Animais Domésticos/normas , Galinhas , Ovos , Meio Ambiente , Criação de Animais Domésticos/economia , Criação de Animais Domésticos/métodos , Bem-Estar do Animal , Animais , Feminino , Inocuidade dos Alimentos , Países Baixos , Oviposição/fisiologia
16.
Artigo em Inglês | MEDLINE | ID: mdl-24109942

RESUMO

Urinary incontinence (UI) is a very common and serious disorder which can be classified in stress and urge incontinence, the latter mainly caused by an overactive bladder (OAB). A definitive treatment for OAB does not exist yet due to its complex nature. Therefore, more attention must be focused on improving the patient's quality of life. A device able to alert the patient to development of a voiding contraction would be highly desirable, enabling actions to avoid incontinence. The main hypothesis of this work is that a voiding contraction is preceded by a consistent change in the pattern of intravesical pressure (p(ves)). We developed an algorithm based on frequency analysis of p(ves) recordings of two strains of rats whose bladders were first filled with saline (S fillings) and then with acetic acid (AA fillings); the latter was used as model for OAB in rats. The algorithm was designed to provide an alarm when an increase in the range 0.2-0.6 Hz of the amplitude spectrum was detected. The accuracy of the algorithm has been tested and quantified, successful alarms were those taking place within fifty seconds before the start of voiding. Although the results are still very preliminary, due to the low number of tested animals, they seem encouraging since, in five rats, only one showed a percentage of success lower than 50%, with one rat reaching 100%. The accuracy of the algorithm is affected by the choice of the values for the controlling parameters, which have been set the same for all rats; future developments might include individual values for each rat.


Assuntos
Algoritmos , Bexiga Urinária/fisiologia , Ácido Acético/farmacologia , Animais , Área Sob a Curva , Masculino , Contração Muscular/efeitos dos fármacos , Curva ROC , Ratos , Ratos Nus , Ratos Wistar , Solução Salina Hipertônica/farmacologia , Bexiga Urinária/efeitos dos fármacos , Micção
17.
Artigo em Inglês | MEDLINE | ID: mdl-24109970

RESUMO

This study presents a novel single compartment model for in vitro electrophysiological studies of the rat urinary bladder. We tested the functionality and suitability of FC-770 (a Perflurocarbon) for in vitro recording of nerve activity arising from the bladder in a single compartment setup. We have also favorably tested stimulation of the bladder via the bladder nerves in FC-770. The organ viability was monitored by recording spontaneous contractions of the bladder for a certain time. We propose the use of FC-770 as a fluid for nerve recording/stimulation in vitro as well as for maintaining organ viability, over the commonly used two compartmental methods.


Assuntos
Eletrofisiologia/instrumentação , Eletrofisiologia/métodos , Fluorocarbonos/química , Bexiga Urinária/inervação , Bexiga Urinária/fisiologia , Animais , Estimulação Elétrica , Técnicas In Vitro , Ratos , Ratos Nus , Ratos Wistar , Processamento de Sinais Assistido por Computador
18.
Food Chem ; 141(2): 1489-95, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23790943

RESUMO

Dietary intake is the predominant route for human exposure to perfluorooctane sulfonic acid (PFOS). Single pollution events may thus affect human exposure if polluted ground and water is used to produce animal feed or food. In this study, a physiologically based pharmacokinetic (PBPK-) model is derived that describes the uptake of PFOS from contaminated feed by cows and its subsequent elimination through the cows' milk. Parameter values of the model were estimated by fitting to experimental data of a cow feeding trial. Model calculations showed that almost all PFOS ingested is excreted through the cows' milk. The elimination rate, however, was low as the estimated half-life in the cow was 56days and it may, thus, take a long time after an initial pollution event to produce PFOS-free milk. The derived model can be used to estimate the transfer of PFOS through the dairy food chain and can be used for comparison of various contamination routes.


Assuntos
Ácidos Alcanossulfônicos/química , Ração Animal/análise , Bovinos/metabolismo , Poluentes Ambientais/química , Fluorocarbonos/química , Contaminação de Alimentos/análise , Leite/química , Ácidos Alcanossulfônicos/metabolismo , Animais , Qualidade de Produtos para o Consumidor , Poluentes Ambientais/metabolismo , Fluorocarbonos/metabolismo , Meia-Vida , Humanos , Leite/metabolismo
19.
Artigo em Inglês | MEDLINE | ID: mdl-22934894

RESUMO

The phenological development of cereal crops from emergence through flowering to maturity is largely controlled by temperature, but also affected by day length and potential physiological stresses. Responses may vary between species and varieties. Climate change will affect the timing of cereal crop development, but exact changes will also depend on changes in varieties as affected by plant breeding and variety choices. This study aimed to assess changes in timing of major phenological stages of cereal crops in Northern and Central Europe under climate change. Records on dates of sowing, flowering, and maturity of wheat, oats and maize were collected from field experiments conducted during the period 1985-2009. Data for spring wheat and spring oats covered latitudes from 46 to 64°N, winter wheat from 46 to 61°N, and maize from 47 to 58°N. The number of observations (site-year-variety combinations) varied with phenological phase, but exceeded 2190, 227, 2076 and 1506 for winter wheat, spring wheat, spring oats and maize, respectively. The data were used to fit simple crop development models, assuming that the duration of the period until flowering depends on temperature and day length for wheat and oats, and on temperature for maize, and that the duration of the period from flowering to maturity in all species depends on temperature only. Species-specific base temperatures were used. Sowing date of spring cereals was estimated using a threshold temperature for the mean air temperature during 10 days prior to sowing. The mean estimated temperature thresholds for sowing were 6.1, 7.1 and 10.1°C for oats, wheat and maize, respectively. For spring oats and wheat the temperature threshold increased with latitude. The effective temperature sums required for both flowering and maturity increased with increasing mean annual temperature of the location, indicating that varieties are well adapted to given conditions. The responses of wheat and oats were largest for the period from flowering to maturity. Changes in timing of cereal phenology by 2040 were assessed for two climate model projections according to the observed dependencies on temperature and day length. The results showed advancements of sowing date of spring cereals by 1-3 weeks depending on climate model and region within Europe. The changes were largest in Northern Europe. Timing of flowering and maturity were projected to advance by 1-3 weeks. The changes were largest for grain maize and smallest for winter wheat, and they were generally largest in the western and northern part of the domain. There were considerable differences in predicted timing of sowing, flowering and maturity between the two climate model projections applied.


Assuntos
Agricultura/métodos , Mudança Climática , Produtos Agrícolas/crescimento & desenvolvimento , Grão Comestível/crescimento & desenvolvimento , Agricultura/tendências , Avena/crescimento & desenvolvimento , Europa (Continente) , Topos Floridos/crescimento & desenvolvimento , Previsões/métodos , Germinação , Humanos , Modelos Biológicos , Modelos Estatísticos , Estações do Ano , Sementes/crescimento & desenvolvimento , Análise Espaço-Temporal , Triticum/crescimento & desenvolvimento , Zea mays/crescimento & desenvolvimento
20.
Poult Sci ; 91(9): 2376-81, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22912476

RESUMO

Based on a data set on Campylobacter and Salmonella prevalence in the broiler supply chain, collected during the period 2002 through 2005 in the Netherlands, farm- and slaughterhouse-specific characteristics were tested for their effect on Campylobacter and Salmonella prevalence at different stages of the broiler supply chain. Three different sampling points were considered: departure from the farm, arrival at the slaughterhouse, and the end of the slaughterline. Strong associations were found between Salmonella and Campylobacter prevalence at a particular sampling point and their prevalence at the preceding point of the chain. Statistical analyses showed that the country of origin of the broiler farm had a significant effect on the prevalence of Salmonella and Campylobacter at slaughterhouse arrival. The feeding company delivering to the farm also showed a significant effect on the occurrence of both pathogens at departure from the broiler farm. The prevalence of Campylobacter decreased with an increasing number of birds per flock, whereas the prevalence of Salmonella increased with an increasing number of birds per flock. The number of flocks processed within a specific slaughterhouse was not associated with an increased or decreased prevalence of Campylobacter and Salmonella. The results provide more insight into factors related to the occurrence of both pathogens and in understanding their epidemiology. The results can be supportive in decision making on measures to reduce the contamination of broiler products with Salmonella and Campylobacter.


Assuntos
Matadouros/normas , Criação de Animais Domésticos/métodos , Criação de Animais Domésticos/normas , Campylobacter/isolamento & purificação , Carne/microbiologia , Salmonella/isolamento & purificação , Animais , Galinhas/microbiologia , Microbiologia de Alimentos
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