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1.
Campylobacter jejuni isolated from raw poultry meat collected at retail shops in Denmark in the period 1996-2003 were tested for susceptibility to seven antimicrobial agents. The food samples consisted of raw chicken meat and other raw poultry meat of domestic or imported origin. The highest levels of resistance among C. jejuni were observed for tetracycline, nalidixic acid and ciprofloxacin, whereas macrolide resistance was rarely detected. C. jejuni originating from other poultry meat (mainly duck and turkey meat) exhibited the highest occurrences of antimicrobial resistance monitored; approximately one third of the isolates were tetracycline resistant (N=100). Among chicken meat isolates, the occurrence of tetracycline resistance was significantly higher (P<0.005) in C. jejuni isolated from imported chicken meat (N=88) than in C. jejuni from Danish chicken meat (N=367). The same tendency was observed for chloramphenicol, nalidixic acid and ciprofloxacin (P<0.05). The trends in resistance in the period 1996-2003 among C. jejuni isolates from chicken meat indicate a decrease in the occurrence of resistance towards fluoroquinolones. This may be due to reduced application of fluoroquinolones for food animals. Monitoring of the occurrence of antimicrobial resistance in C. jejuni isolated from raw uncooked poultry has been performed on a yearly basis since 1996, thus providing useful insight into consumer exposure to antimicrobial-resistant C. jejuni.  相似文献   

2.
A simple and sensitive method for detecting enrofloxacin, a major veterinary fluoroquinolone, was developed. Monoclonal antibody specific for enrofloxacin was immobilised on a chip and fluorescent dye-labelled microparticles were covalently bound to the enrofloxacin molecules. Enrofloxacin in solution competes with the microparticle-immobilised enrofloxacin (enroMPs) to bind to the antibody on the chip. The presence of enrofloxacin was verified by detecting the fluorescence of enrofloxacin-bound microparticles. Under optimum conditions, a high dynamic range was achieved at enrofloxacin concentrations ranging from 1 to 1000 μg kg?1. The limits of detection and quantification for standard solutions were 5 and 20 μg kg?1 respectively, which are markedly lower than the maximum residue limit. Using simple extraction methods, recoveries from fortified beef, pork and chicken samples were 43.4–62.3%. This novel method also enabled approximate quantification of enrofloxacin concentration: the enroMP signal intensity decreased with increasing enrofloxacin concentration. Because of its sensitivity, specificity, simplicity and rapidity, the method described herein will facilitate the detection and approximate quantification of enrofloxacin residues in foods in a high-throughput manner.  相似文献   

3.
Campylobacter has been the most prevalent microorganism associated with foodborne gastroenteritis in developed countries in the last years. The consumption of contaminated chicken meat is the main source of campylobacteriosis in humans. However, in developing countries, Campylobacter has not been recognized as a food safety problem. Here, we provide an overview of studies focusing on occurrence of Campylobacter in Brazilian chicken processing chain, epidemiological data, contamination sources, antimicrobial resistance and fields where more studies are needed. Over the past 15 years, only five foodborne outbreaks involving 37 cases of campylobacteriosis were reported in Brazil. However, the occurrence of Campylobacter in samples of carcasses and chicken products was about 32.7%, and the microbial load ranged from <0.30 to 5.15 log10 CFU. This pathogen was also found in feces, caecum, intestine and cloaca of chicken (50.9%), chicken litter (65.4%), and water (13.7%). The most prevalent species identified in the studies were C. jejuni (80%) and C. coli (19.6%). In addition, high antimicrobial resistance rates were noted for cephalosporins (98.5–100%), quinolones (84.5%), and fluoroquinolones (77.6–82.8%). This review demonstrates that Campylobacter seems to be an important pathogen in the chicken processing chain and, consequently, for public health in Brazil.  相似文献   

4.
In order to compare human and retail poultry meat thermophilic Campylobacter isolates originating in a regional area in Western Finland, minimum inhibitory concentration (MICs) for six antimicrobials (96 isolates) and pulsed-field gel electrophoresis (PFGE) (102 isolates) were analysed. Campylobacter spp. were detected in 10.5% out of 305 fresh poultry products studied; 29 (90.5%) isolates were identified as Campylobacter jejuni. Among the 70 human isolates, 66 (94.3%) isolates were identified as C. jejuni. Only one C. jejuni domestic poultry isolate showed resistance (ampicillin), whereas domestic human C. jejuni isolates were more commonly resistant to ciprofloxacin, nalidixic acid, ampicillin and tetracycline. The resistance in foreign human isolates was significantly more common than among domestic isolates. PFGE analysis with KpnI restriction enzyme resulted in 59 different PFGE types among the poultry and human isolates. Three types were detected first in poultry meat and thereafter during the following month in domestic human samples, whereas the other conjoint types were detected only after many months. This study suggests that poultry products play only a minor role in human campylobacteriosis in the study area and that the resistance found in domestic human isolates is not likely related to retail poultry meat products.  相似文献   

5.
In 2005, the FDA withdrew approval for the use of fluoroquinolones in live poultry production. To assess any changes in countable numbers of ciprofloxacin-resistant Campylobacter before and after the fluoroquinolone withdrawal, retail whole raw chicken carcasses (RTCC) purchased in Northwest Arkansas from 2004 to 2006 were sampled for this purpose. Using a previously published direct-plating method developed in our laboratory, we quantified trends of Campylobacter and ciprofloxacin-resistant Campylobacter loads by direct plating whole chicken carcass rinses on Campylobacter agar (CA) or Campylobacter agar containing 8.6 µg/ml ciprofloxacin (CCA). Countable populations of Campylobacter were recovered from 74, 96, and 63% of carcasses sampled in 2004, 2005, and 2006 respectively. The percentages of carcasses with minimum detectable levels of ciprofloxacin-resistant Campylobacter were 20, 42 and 33%, sampled in 2004, 2005 and 2006, respectively. Our 3 year analysis in one geographical area indicated a persistence of Campylobacter and ciprofloxacin-resistant Campylobacter on retail raw chicken carcasses despite the cessation of fluoroquinolone use in poultry production.  相似文献   

6.
ABSTRACT

An increasing concern about food safety has been observed over the years. The presence of drugs residues in food is one of the major subjects of research in food safety. Feedingstuffs can be responsible for carryover into the food chain of residues of several drugs. This paper describes the development, validation and application of a fast and simple method for analysis of 24 antibiotic residues in feedingstuffs for cattle, pigs and poultry. Analytes include compounds from different antimicrobials classes, such as sulfonamides (sulfadiazine, sulfamethazine, sulfamethoxazole, sulfaquinoxaline, sulfachlorpyridazine, sulfadoxine, sulfadimethoxine, sulfizoxazole, sulfamerazine and sulfathiazole), fluoroquinolones (ciprofloxacin, enrofloxacin, norfloxacin, danofloxacin, difloxacin, sarafloxacin, flumequine, nalidixic acid and oxolinic acid), tetracyclines (tetracycline, doxycycline, oxytetracycline and chlortetracycline) and trimethoprim. Samples were extracted with methanol:water (70:30) 0.1% formic acid, followed by clean-up steps using centrifugation, low-temperature purification (LTP) and ultracentrifugation. Instrumental analysis was performed using liquid chromatography coupled to tandem mass spectrometry. Chromatographic separation was achieved using a C18 column and a mobile phase composed of acetonitrile and water, both with 0.1% formic acid. Validation parameters such as limit of detection (LOD), limit of quantification (LOQ), selectivity, linearity, accuracy, precision, decision limit (CCα) and detection capability (CCβ) were determined and meet the adopted criteria. LOD and LOQ were set to 30 and 75 µg kg?1, respectively. Inter-day precision were in the range from 4.0 to 11.1%, and linearity provides values of r2 above 0.95 for all analytes. The optimised method was applied to the analysis of more than 1500 real samples within the period 2012–2017. Non-compliant results were discussed and classified in terms of analytes, feed types and target species. Multivariate analysis of the data was performed using principal component analysis.  相似文献   

7.
Campylobacteriosis is one of the most common bacterial infections worldwide causing economic costs. The high prevalence of Campylobacter spp. in poultry meat is a result of several contamination and cross‐contamination sources through the production chain. Moreover, survival mechanisms, such as biofilm formation, viable but nonculturable state, and antimicrobial resistance, enable its persistence during food processing. Therefore, mitigation strategies are necessary in order to avoid and/or inactivate Campylobacter at farm, abattoir, industry, and retail level. In this review, a number of potential strategies and novel technologies that could reduce the prevalence of Campylobacter in poultry meat have been identified and evaluated to provide a useful overview. At farm level for instance, biosecurity, bacteriocins, probiotics, feed and water additives, bacteriophages, and vaccination could potentially reduce colonization in chicken flocks. However, current technologies used in the chicken slaughter and processing industry may be less effective against this foodborne pathogen. Novel technologies and strategies such as cold plasma, ultraviolet light, high‐intensity light pulses, pulsed electric fields, antimicrobials, and modified atmosphere packaging are discussed in this review for reducing Campylobacter contamination. Although these measures have achieved promising results, most have not been integrated within processing operations due to a lack of knowledge or an unwillingness to implement these into existing processing systems. Furthermore, a combination of existing and novel strategies might be required to decrease the prevalence of this pathogen in poultry meat and enhance food safety. Therefore, further research will be essential to assess the effectiveness of all these strategies.  相似文献   

8.
The level of antibiotic multiresistance of Campylobacter strains from chicken was evaluated and responses to the bactericidal effects of organic acids were analyzed. Strains (76) isolated from chicken were analyzed for resistance to antibiotics and acid shock. A high strain resistance to fluoroquinolones (ciprofloxacin and nalidixic acid) was observed, with cross resistance to both drugs in 41% of strains. A low resistance was observed for amoxicillin, erythromycin, and gentamicin. Campylobacter jejuni was the most resistant species. Antibacterial activities against multiresistant Campylobacter strains were observed using acetic, citric, and ascorbic acids at minimum bactericidal concentrations (MBC) ranging from 0.3 to 3 mg/mL. Acetic acid was the most efficient acid with the lowest MBC value. However, a contact time of 4 h was required for an efficient effect against Campylobacter contaminated chicken skin. Using organic acids in the poultry production chain can reduce propagation of antibiotic multiresistant strains of Campylobacter.  相似文献   

9.
This study explored the potential use of seven congeners of polychlorinated biphenyls (PCBs-7) as indicator compounds for the presence of dioxins and PCBs in food samples, as part of the routine surveillance programme of a public health agency. Samples of 24 foodstuffs with high fat content were collected (ten fresh fish, six dairy products, five meat and three eggs). Duplicate analyses were performed. A research laboratory tested samples for seven polychlorinated dibenzo-p-dioxin (PCDDs), ten dibenzofurans (PCDFs) and twelve dioxin-like PCBs, with limits of detection in the range of ng kg?1 (ppt). The public health services official control laboratory tested samples for PCBs-7, with a limit of quantification of 5 µg kg?1 (ppb). The research laboratory detected the presence of dioxins and dioxin-like PCBs in all samples; fish samples had the highest levels (0.04–10.3 pg WHO-TEQ g?1). The public health service official control laboratory detected PCBs-7 only in five samples, which were all fish. Comparing the results in the two laboratories there seems to be an association between the detection of PCB-7 and the presence of higher levels of PCDD/Fs and dioxin-like PCBs. The use of PCB-7 as an indicator compound may be a practical surveillance strategy for those foodstuffs with higher concentrations of dioxin-like congeners.  相似文献   

10.
Brominated dioxins (PBDD/Fs) and 17 polybrominated diphenylether (PBDE) congeners including BDE-209 were analysed in 100 composite samples of commonly consumed foods of animal origin, prepared from ten to 40 individual subsamples of each type. These included 30 samples of milk from farms; eggs from chickens; fat from cows, pigs, sheep, and poultry; and liver from cows, pigs, sheep, horses, and poultry. The ISO 17025-accredited analytical methodology used, follows similar guidelines as given for chlorinated dioxins and polychlorinated biphenyls (PCBs) in European Commission Directive 2002/69/EC. Apart from some samples of milk, PBDD/Fs and PBDEs were detected in all food types. Concentrations ranged from 0.31 µg kg?1 Σ17 PBDEs for a sample of milk to 37.5 µg kg?1 Σ17 PBDEs for a sample of liver. The corresponding range for the PBDD/F toxicity (computed using analogous PCDD/F toxic equivalency factors (TEFs)) was 0.09 ng TEQ kg?1 to approximately 3.5 ng TEQ kg?1. The detection of these compounds, in particular PBDD/Fs, is consistent with the increased use and disposal of brominated organic compounds.  相似文献   

11.
A survey was carried out on the occurrence of dinitrocarbanilide (DNC), the marker residue for nicarbazin, in poultry produced in Ireland during 2002–2004. Liver (n?=?736) and breast muscle samples (n?=?342) were tested. DNC residues were found in 40 and 26% of liver and breast muscle samples at levels greater than 12.5 and 5?µg?kg?1, respectively. DNC residues were found at >200?µg?kg?1 in 12 and 0% of liver and muscle samples, respectively. Samples of breast muscle (n?=?217) imported from 11 countries were also tested for DNC residues. A lower incidence of DNC residues (6%) was found in imported breast muscle. Egg samples (n?=?546) were tested and DNC residues were found in nine samples, with levels ranging between 14 and 122?µg?kg?1. Analysis of poultry, carried out as part of official food inspection in the period 2004–2006, indicated a reduction in the number of broiler liver samples containing DNC at >200?µg?kg?1, to approximately 7%. Low levels of DNC residues continue to be found in <2% of egg samples.  相似文献   

12.
The current study was carried out to determine the antimicrobial resistance profiles and evaluate some molecular characteristics of a set of Salmonella and Campylobacter isolates recovered from production line turkeys in the Midwest region of the United States. A total of 94 birds identified as being positive for both Salmonella and Campylobacter spp. were selected for study. All Salmonella isolates were examined for antimicrobial resistance using the methods employed in the National Antimicrobial Resistance Monitoring System (NARMS). Campylobacter isolates were subjected to similar analysis using the Etest®. In addition, polymerase chain reaction (PCR) was carried out to determine the presence of the antimicrobial resistance associated genes, integrase (int1), class 1 integrons (Salmonella and Campylobacter) and a multidrug efflux pump (Campylobacter spp.). Results from the study showed that the Salmonella and Campylobacter isolates examined displayed resistance to a number of antimicrobials, with Salmonella and Campylobacter isolates being resistant to at least three antimicrobials while some isolates showed resistances to 6 or 8 different antimicrobials. In addition, 68.1% of the Salmonella isolates tested were found to be positive for the class I integrase gene (int1), 28.7% possessed a 1000 bp gene cassette and 17% possessed an 800 bp gene cassette. All Campylobacter isolates were negative for int1, but 36.2% tested positive for the Campylobacter multidrug efflux pump (CmeB). A considerable number of Salmonella and Campylobacter isolates tested displayed varying degrees of antimicrobial resistance as well as the presence of some factors associated with the carriage and persistence of antimicrobial resistance. Similarities in the types of antimicrobial resistance observed in Campylobacter and Salmonella strains was evident. The results of this study suggest that prescribing practice at the farm level may be a factor in promoting antimicrobial resistance in more than one species of organism. Such practices may, therefore, contribute to the potential health risk for consumers should micro-organisms carrying multiple antimicrobial resistances enter the food chain. This study may be one of the first to report on the incidence of the multidrug efflux pump (CmeB) in Campylobacters recovered from processed turkeys. The antimicrobial resistance and molecular characteristics of Salmonella and Campylobacter is discussed.  相似文献   

13.
Poultry is thriving across the globe. Chicken meat is the most preferred poultry worldwide, and its popularity is increasing. However, poultry also threatens human hygiene, especially as a fomite of infectious diseases caused by the major foodborne pathogens (Campylobacter, Salmonella, and Listeria). Preventing pathogenic bacterial biofilm is crucial in the chicken industry due to increasing food safety hazards caused by recurring contamination and the rapid degradation of meat, as well as the increased resistance of bacteria to cleaning and disinfection procedures commonly used in chicken processing plants. To address this, various innovative and promising strategies to combat bacterial resistance and biofilm are emerging to improve food safety and quality and extend shelf-life. In particular, natural compounds are attractive because of their potential antimicrobial activities. Natural compounds can also boost the immune system and improve poultry health and performance. In addition to phytochemicals, bacteriophages, nanoparticles, coatings, enzymes, and probiotics represent unique and environmentally friendly strategies in the poultry processing industry to prevent foodborne pathogens from reaching the consumer. Lactoferrin, bacteriocin, antimicrobial peptides, cell-free supernatants, and biosurfactants are also of considerable interest for their prospective application as natural antimicrobials for improving the safety of raw poultry meat. This review aims to describe the feasibility of these proposed strategies and provide an overview of recent published evidences to control microorganisms in the poultry industry, considering the human health, food safety, and economic aspects of poultry production.  相似文献   

14.
Analysis of residual levels of tetracyclines (TCs) in chicken meat was performed using a validated liquid chromatography coupled with a tandem mass spectrometry (LC-MS/MS) technique. Overall, the recoveries for TCs ranged from 56.9% to 101.2%, with standard deviations of 4.5–13.2%. Detection limits ranged from 7.9 to 14.6?µg?kg?1. In four of 60 samples, doxycycline (DXC) was determined in a range from 19.9 to 35.6?µg?kg?1; and in one sample tetracycline was detected at 17.2?µg?kg?1. Chlortetracycline (CTC) and oxytetracycline (OTC) were not detected in any of the tested samples. This study indicates that chicken meat sold in Bursa, Turkey, contained some residues of TCs. Therefore, stricter regulations for the use of antibiotics in the poultry industry and the monitoring of drug residues in chicken meat prior to marketing are needed. Finally, this method has been applied successfully for the confirmation of TCs in chicken meat.  相似文献   

15.
Beef meat is an important food that can be contaminated by pesticides. This study aimed to optimize a multiresidue method for identification and quantification of pesticides in beef meat by liquid chromatography coupled to mass spectrometry detection (LC-MS). The extraction and clean-up procedures were adapted from the QuECHERS method. From the 188 analytes tested, the method was validated as qualitative method for 19 compounds and as quantitative method for 152 compounds. The results were satisfactory, yielding coefficients of variation of less than 20% and recoveries ranging from 70% to 120% and expanded uncertainty of less than 50%. The quantification limit was typically 10 µg kg?1 (but 25 µg kg?1 for 12 of the compounds) and the detection limit was 5.0 µg kg?1. Thirty-two real samples of commercialized beef meat were analyzed without any residual pesticide being found. Thus, the results showed that the multiresidue method for detecting 171 pesticides, using adapted QuECHERS for extraction and LC-MS for detection, is suitable for analyzing beef meat.  相似文献   

16.
This paper reports levels of polybrominated diphenyl ethers (PBDEs) in a wide range of foods of animal origin and estimates their dietary exposure for secondary school students in Hong Kong, China. Dietary exposure to PBDEs was estimated using local food consumption data obtained from secondary school students in 2000 and the concentrations of PBDEs in food samples taken from local market in 2008. The PBDE levels on a fresh weight basis for fish ranged from 13 to 6600 pg g?1, for seafood and seafood products ranged from 15 to 1200 pg g?1, for meat and meat products ranged from 23 to 3500 pg g?1, for poultry ranged from 68 to 670 pg g?1, for eggs ranged from 280 to 800 pg g?1, and for dairy products ranged from 12 to 480 pg g?1. The dietary exposures of secondary school students for the average and high consumers were estimated to be 2.6 and 6.4 ng kg?1 body weight day?1, respectively. According to the Joint FAO/WHO Expert Committee on Food Additives (JECFA), for the more toxic PBDE congeners, adverse effects would be unlikely to occur in laboratory animals at doses of less than approximately 100 µg kg?1 body weight day?1. The resulting margins of exposures (38,000 for average consumers and 16,000 for high consumers) showed that the estimated dietary exposures of secondary school students were far below any adverse effect dose observed in laboratory animals and were therefore of low concern for human health.  相似文献   

17.
Mean counts of Escherichia coli were determined for 54 samples of organic pork meat, and in 67 samples of conventional pork meat. Up to three E. coli strains from each sample were analysed by an agar disk diffusion assay for their resistance to ampicillin, chloramphenicol, cephalotin, doxycycline, enrofloxacin, gentamicin, nitrofurantoin, sulfisoxazole and streptomycin by the agar disk diffusion method. Results indicated that the presence of E. coli was significantly (P < 0.05) higher in organic pork meat as compared to conventional pork meat. Isolates from organic pork meat exhibited lower levels of antimicrobial resistance against ampicillin (P < 0.0001), doxycycline (P < 0.0001) and sulfisoxazole (P < 0.0001), as compared to isolates from conventional meat. Moreover, presence of multi-resistant E. coli strains was significantly (P < 0.0001) higher in conventional pork meat as compared to organic pork meat, the largest differences being observed for isolates resistant to combinations of ampicillin, sulfisoxazol and/or doxycycline. Organically-farmed pork samples showed significantly lower development of antimicrobial resistance in E. coli, thus contributing to reduce the development and spread of antimicrobial resistance among these food-borne bacteria.  相似文献   

18.
Abstract : Because of the carcinogenic nature of many N-nitroso compounds, there is concern about their presence in foods. This paper presents some data on the levels of two non-volatile compounds (2-(hydroxymethyl)-N-nitrosothiazolidine-4-carboxylic acid (HMNTCA) and 2-(hydroxymethyl)-N-nitrosothiazolidine (HMNTHZ)) in various smoked foods such as 25 cured meats, eight smoked fish and seafoods, 15 smoked poultry products, and 17 smoked cheeses. All samples were negative for HMNTHZ, but 11 of the cured meats, six poultry products and two smoked fish contained HMNTCA at levels of 10–260 μg kg?1. Upon frying, appreciable levels of HMNTHZ were formed in only one of 10 samples of cured meat products. The smoked cheeses were all negative for HMNTCA.  相似文献   

19.
Lead-based hunting ammunitions are still common in most countries. On impact such ammunition releases fragments which are widely distributed within the carcass. In Norway, wild game is an important meat source for segments of the population and 95% of hunters use lead-based bullets. In this paper, we have investigated the lead content of ground meat from moose (Alces alces) intended for human consumption in Norway, and have predicted human exposure through this source. Fifty-two samples from different batches of ground meat from moose killed with lead-based bullets were randomly collected. The lead content was measured by atomic absorption spectroscopy. The lead intake from exposure to moose meat over time, depending on the frequency of intake and portion size, was predicted using Monte Carlo simulation. In 81% of the batches, lead levels were above the limit of quantification of 0.03?mg?kg?1, ranging up to 110?mg?kg?1. The mean lead concentration was 5.6?mg?kg?1, i.e. 56 times the European Commission limit for lead in meat. For consumers eating a moderate meat serving (2?g?kg?1 bw), a single serving would give a lead intake of 11?µg?kg?1 bw on average, with maximum of 220?µg?kg?1 bw. Using Monte Carlo simulation, the median (and 97.5th percentile) predicted weekly intake of lead from moose meat was 12?µg?kg?1 bw (27?µg?kg?1 bw) for one serving per week and 25?µg?kg?1 bw (45?µg?kg?1 bw) for two servings per week. The results indicate that the intake of meat from big game shot with lead-based bullets imposes a significant contribution to the total human lead exposure. The provisional tolerable weekly intake set by the World Health Organization (WHO) of 25?µg?kg?1 bw is likely to be exceeded in people eating moose meat on a regular basis. The European Food Safety Authority (EFSA) has recently concluded that adverse effects may be present at even lower exposure doses. Hence, even occasional consumption of big game meat with lead levels as those found in the present study may imply an increased risk for adverse health effects. Children and women of child-bearing age are of special concern due to the neurodevelopmental effects of lead.  相似文献   

20.
Acrylamide in Thai-conventional snacks was analysed by GC/MS with a linear response ranged of 5–50?µg and r 2?>?0.99. The limit of detection (s/n?=?(3) and limit of quantification (s/n?=?10) were 4 and 15?µg?kg?1, respectively, and RSD?<?2%. Acrylamide in 19 food samples ranged from <15?µg?kg?1 to 1.26?mg?kg?1 with highest concentrations in Kanom Jak. Moderate levels (150–500?µg?kg?1) were detected mostly in deep-fried products, especially sweet potato and taro crisps, Kanom Kai Hong, banana fritters, durian chips and spring rolls. Thai-conventional snacks possessed low concentrations (<150?µg?kg?1) including Khao Larm, Pa Tong Koo, sweet banana crisps and deep-fried Chinese wonton. Acrylamide was lowest (<15?µg?kg?1) in fish strips, rice crackers, Hoi Jor and fried fish balls. Dietary habits by 400 tourists indicate a daily intake of acrylamide <150?ng, well below a toxic dose.  相似文献   

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