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M Madsen

Publications and source records attributed to M Madsen.

At least 37 records · Page 2Linked to original sources
PubMed2003

Cross-contamination with Salmonella on a broiler slaughterhouse line demonstrated by use of epidemiological markers.

AIMS: To investigate contamination of surfaces on a poultry slaughter line from infected poultry and subsequent cross-contamination of non-infected poultry. METHODS AND RESULTS: A broiler slaughterhouse was investigated for the presence of Salmonella on 17 defined points over two 1-week periods. Flocks supplied to slaughter and neck skin samples from processed chicken were likewise investigated. Salmonella was detected in 10 out of 18 flocks at ante-mortem inspection, while seven flocks tested positive in the finished products. Equipment at all but one control point at the slaughter line tested positive at least once during the study. The chicken receiving area was the most contaminated. By comparison of typing results from serotyping, plasmid profile typing and phage typing, direct evidence for cross-contamination with Salm. serotype Typhimurium, Salm. Serotype 4.12:b:- and Salm. serotype Virchow on the slaughter line was obtained for four of the flocks. The cleaning procedure in place did not remove all Salmonella from the contaminated areas. CONCLUSIONS: Evidence for contamination of equipment on a slaughter line and subsequent cross-contamination to non-infected chicken was provided by typing methods. SIGNIFICANCE AND IMPACT OF THE STUDY: This study has provided detailed information on cross-contamination on a slaughter line by the use of phage typing and plasmid profiling. The study stresses the importance of controlling Salmonella in the primary production, as contamination of the equipment on the slaughter line will act as a vehicle to contaminate finished products. Cleaning procedures on slaughter lines cannot be expected to control this problem with the current equipment.

Abattoirs↗
PubMed2003

PCR detection of seven virulence and toxin genes of Campylobacter jejuni and Campylobacter coli isolates from Danish pigs and cattle and cytolethal distending toxin production of the isolates.

AIMS: To study the prevalence of seven virulence and toxin genes, and cytolethal distending toxin (CDT) production of Campylobacter jejuni and C. coli isolates from Danish pigs and cattle. METHODS AND RESULTS: The presence of the cadF, ceuE, virB11, flaA, cdtA, cdtB, cdtC and the cdt gene cluster among 40 C. jejuni and C. coli isolates was detected by polymerase chain reaction. The CDT production of the isolates was determined on Vero, colon 205 and chicken embryo cells. The cadF, flaA, ceuE and cdtB genes were detected from 100% of the isolates. The cdtA and cdtC genes were found in 95.0 and 90.0% of the isolates, respectively. The cdt gene cluster was detected in 82.5% isolates. Only 7.5% of the isolates were positive for virB11. Ninety-five per cent of the isolates produced CDT in Vero and colon 205 cell assays, and 90% of the isolates produced CDT in chicken embryo cell assays. CONCLUSIONS: High prevalence of the cadF, ceuE, flaA and cdtB genes was found. Data of the prevalence of cdt genes was consistent with the CDT titres produced by the isolates. Campylobacter coli from pigs produced high CDT titres. SIGNIFICANCE AND IMPACT OF THE STUDY: The high prevalence of seven virulence and toxin genes demonstrated that these putative pathogenic determinants are widespread among Campylobacter isolates from pigs and cattle. Campylobacter coli isolates from pigs produced much higher CDT titres compared with C. coli isolates from other sources suggesting that C. coli may be particularly adapted to or associated with this species.

Animals↗
PubMed2003

Evaluation of PCR for detection of Campylobacter in a national broiler surveillance programme in Denmark.

AIMS: To develop and evaluate a rapid and sensitive PCR method for detection of Campylobacter spp. directly from chicken faeces. METHODS AND RESULTS: DNA was isolated from faecal swabs using magnetic beads followed by PCR using a prealiquoted PCR mixture, which had been stored in the freezer. The result could be obtained in <6 h. The method was evaluated on 1282 samples from the Danish surveillance programme for Campylobacter in broilers by comparing with conventional culture. The diagnostic specificity was calculated to be 0.99. The detection limits of the PCR method and of the conventional culture were compared using spiked control material. For both methods the detection limit was 36 CFU ml-1. CONCLUSIONS: It was concluded that the PCR proved useful for detection of Campylobacter in pooled cloacal swabs from broilers. SIGNIFICANCE AND IMPACT OF THE STUDY: By taking cloacal samples in the broiler flocks the technique can be used as an important tool for planning and directing the broiler slaughtering process. This will be a great help in minimizing the risk of contaminating Campylobacter-free flocks at the abattoir.

Abattoirs↗
PubMed2003

Identification of campylobacteria isolated from Danish broilers by phenotypic tests and species-specific PCR assays.

AIMS: To validate a phenotypic Campylobacter species identification method employed to identify campylobacters in broilers by comparison with campylobacterial species identification using various species-specific PCR analyses. METHODS AND RESULTS: From a collection of 2733 phenotypically identified campylobacterial cultures, 108 Campylobacter jejuni cultures and 351 campylobacterial cultures other than Camp. jejuni were subjected to various species-specific PCR assays. On the basis of the genotypic tests, it was demonstrated that Camp. jejuni and Camp. coli constituted approx. 99% of all cultures, while other species identified were Helicobacter pullorum, Camp. lari and Camp. upsaliensis. However, 29% of the 309 Camp. coli cultures identified by phenotypic tests were hippurate-variable or negative Camp. jejuni cultures, whereas some Camp. lari cultures and unspeciated campylobacter cultures belonged to H. pullorum. It was also notable that 2-6% of the cultures were, in fact, mixed cultures. CONCLUSIONS: The phenotypic identification scheme employed failed to appropriately differentiate Campylobacter species and particularly to identify the closely related species, H. pullorum. SIGNIFICANCE AND IMPACT OF THE STUDY: Future phenotypic test schemes should be designed to allow a more accurate differentiation of Campylobacter and related species. Preferably, the phenotypic tests should be supplemented with a genotypic strategy to disclose the true campylobacterial species diversity in broilers.

Animals↗
PubMed2003

Trends in incidence and case fatality rates of acute myocardial infarction in Denmark and Sweden.

OBJECTIVE: To compare the incidence and case fatality of acute myocardial infarction in Denmark and Sweden. DESIGN: A cohort study, linking the national registries of hospital admissions and causes of death in the two countries. PATIENTS: All admissions and deaths with acute myocardial infarction as primary or secondary diagnosis were extracted (Denmark, 1978 to 1998; Sweden, 1987 to 1999). MAIN OUTCOME MEASURES: The incidence was estimated using the first acute myocardial infarct for each patient. Case fatality was estimated in the first 28 days after acute myocardial infarction, including prehospital deaths. All rates were adjusted for age. RESULTS: The incidence of myocardial infarction and the case fatality declined significantly among all subgroups of patients. Case fatality was higher in Denmark early in the study period (1987-1990) than in Sweden. The odds ratios (OR) ranged from 1.28 to 1.50 in the four age groups. In 1994-1999, the prognosis of patients younger than 75 years did not differ. Patients aged 75-94 years still fared worse in Denmark (OR 1.21, 95% confidence interval 1.17 to 1.27). Women aged 30-54 years had a worse prognosis than men in both Denmark and Sweden (OR associated with male sex 0.85 and 0.90, respectively). In contrast, for patients older than 65 years, women had a better prognosis than men. This difference in the effect of sex with age was significant (p < 0.0001) and did not change over time. CONCLUSIONS: Case fatality after acute myocardial infarction was notably higher in Denmark than in Sweden in 1987-1991, but in the later periods the prognosis was comparable in the two countries.

Adult↗
PubMed2002

Rapid PCR using nested primers of the 16S rRNA and the hippuricase (hip O) genes to detect Campylobacter jejuni and Campylobacter coli in environmental samples.

Identification of sources Campylobacter infection in the poultry houses is in general problematic due to the lack of reliable methods to detect campylobacteria in environmental samples. Detection of campylobacteria in environmental samples by conventional culture methods is difficult and of limited sensitivity due to the use of selective media, the low number of bacteria in the samples and possibly also due to the presence of non-culturable or sub-lethally injured stages of the bacteria. The present paper describes a rapid PCR assay using nested primers of the 16S rRNA or the hippuricase (hip O) genes to detect Campylobacter jejuni and Campylobacter coli in environmental samples. The sensitivity of the nested PCR was determined to be 0.01 pg/PCR, corresponding to 2-3 colony forming units (cfu) per ml. The nested PCR assays were applied to detect C. jejuni and C. coli in 269 environmental samples collected from ten broiler farms. The sensitivity, specificity and the usefulness of the PCR assay for detection of C. jejuni and C. coli in environmental samples are presented and discussed.

Amidohydrolases↗
PubMed2002

Trends in lifestyle coronary risk factors in the Danish MONICA population 1982-1992.

Myocardial infarction incidence rate declined 3-5% per year during 1982-1992 in the Danish study population of the WHO MONICA Project. We examined whether smoking habits, alcohol intake, dietary habits and physical activity levels changed in the population during the same period. Data from 6695 men and women of ages 30, 40, 50 and 60 y, examined in 1982-4, in 1986-7, and in 1991-2, were analysed to estimate trends. A summary healthy eating index and six scores derived by factor analysis were used to analyse food frequency data. The percentage of smokers declined 1.6% per year in men, and 1.0% per year in 30-, 40- and 50-y-old women, but increased 0.9% per year in 60-y-old women. The percentages of heavy cigarette smoking men and women nevertheless remained constant and close to 30%. Total alcohol intake declined among 30-y-olds, but appeared constant in other age groups. However, among 60-y-old men and among women over 30, the percentage of wine-drinkers rose from 6-11% in 1982-4 to 9-18% in 1991-2. Only 60-y-old men became more physically active at work and only 30-y-old women more so in leisure times. The percentage of individuals with a low healthy eating index decreased and the percentage with a high index increased. More importantly, dietary factor scores showed trends suggesting that very profound and potentially beneficial changes in dietary habits occurred. Lifestyle in the DAN-MONICA population changed in several ways that may have contributed to the declining incidence of myocardial infarction during the 1980s.

Adult↗
PubMed2002

Discrimination of Arcobacter butzleri isolates by polymerase chain reaction-mediated DNA fingerprinting.

AIMS: The objective of this study was to subtype Arcobacter butzleri isolates using RAPD-PCR. METHODS AND RESULTS: Thirty-five A. butzleri isolates obtained from chicken carcasses were examined. PCR-mediated DNA fingerprinting technique with primers of the variable sequence motifs was used to detect polymorphism within the isolates. Eleven distinct DNA profiles were obtained as follows: Of the 35 strains, 10 as profile 4; seven as profile 1; five as profile 3; three as profiles 2 and 9; two as profile 10; one as profiles 5, 6, 7, 8 and 11. CONCLUSIONS: Chicken carcasses sold in markets were found to be contaminated with several different strains of A. butzleri. RAPD-PCR technique was found to be a useful technique for distinguishing A. butzleri isolates. SIGNIFICANCE AND IMPACT OF THE STUDY: The presence of several different A. butzleri strains on chicken carcasses may indicate multiple sources of contamination. The epidemiological role of A. butzleri in human and animal diseases should be investigated further.

Animals↗
PubMed2002

Application of molecular methods for identification of strains classified as Salmonella enterica serovar 6, 7:-:- by conventional serotyping.

An increased prevalence of Salmonella enterica serovar Tennessee (6, 7: z(29):-) was observed in broiler flocks in Denmark in 1994 and a parallel increase in the prevalence of Salmonella enterica serovar 6, 7:-:- was demonstrated, albeit at a lower level. Plasmid profiling and ribotyping revealed similar genotypes and it was speculated that serovar 6, 7:-:- could represent a non-motile variant of Salmonella Tennessee. Re-testing of the Salmonella 6, 7:-:- isolates demonstrated the presence of flagella through positive motility. All isolates but one demonstrated motility using both tube tests and light microscopy of overnight broth cultures. Molecular characterization indicated that all but two isolates previously classified as Salmonella 6, 7:-:, were isolates of Salmonella Tennessee and Salmonella Infantis, exhibiting reduced motility. Re-serotyping and multiplex polymerase chain reaction analysis for the phase 2 gene fljB demonstrated variants of Salmonella Infantis (6, 7: r: z(49)) expressing the R-phase antigen (Rz(49)) and possessing the gene for normal phase 2 antigen H: 1, 5. One of the two undefined strains demonstrated genotypic identity with a Salmonella Livingstone reference strain. The remaining putative 6, 7:-:- strain could not be identified and was genuinely non-motile. Diagnostic procedures performed initially were thus insufficient to differentiate between the different levels of motility and also resulted in mis-serotyping. As similar observations were made with two of 14 isolates received from a foreign laboratory, this may represent a general diagnostic problem.

Animals↗
PubMed2002

Persistence of vancomycin-resistant enterococci (VRE) in broiler houses after the avoparcin ban.

The glycopeptide growth promoter avoparcin was banned from animal production in the EU in 1997 due to concern for the spread of vancomycin-resistant enterococci (VRE) from food animals to humans. In recent Norwegian and Danish studies, extensive occurrence of VRE on broiler farms and in broiler flocks after the avoparcin ban has been reported. The present study was undertaken to investigate the epidemiology of VRE on broiler farms in the absence of the selective pressure exerted by avoparcin. Environmental samples were obtained from five broiler houses after depopulation, cleaning, and disinfection of the houses between rotations, and two consecutive broiler flocks from each house were sampled by taking cloacal swabs from the broilers at the time of slaughter. A total of 69 vancomycin-resistant Enterococcus faecium isolates obtained from broiler flocks and broiler houses were subjected to molecular typing by pulsed-field gel electrophoresis (PFGE). Forty-one PFGE-profiles were observed. VRE with indistinguishable or highly similar PFGE profiles were isolated from consecutive broiler flocks and from environmental samples from the houses in which the flocks were reared, whereas VRE-isolates from different broiler houses and from flocks reared in different houses appeared to be genetically unrelated. These findings indicated that VRE was transmitted between consecutive broiler flocks by clones of resistant bacteria surviving in the broiler houses despite cleaning and disinfection between rotations. Thus, the extensive occurrence of VRE in broiler flocks after the avoparcin ban may be explained by persistence of VRE in the broiler house environment.

Animal Feed↗
PubMed2002

Vancomycin-resistant enterococci (VRE) in broiler flocks 5 years after the avoparcin ban.

The glycopeptide growth promoter avoparcin was banned from animal production in Denmark in 1995. In this study, we investigated the occurrence of vancomycin-resistant enterococci (VRE) in broiler flocks in the absence of the selective pressure exerted by the use of avoparcin. One hundred sixty-two broiler flocks from rearing systems with different histories of avoparcin exposure were investigated for the presence of VRE. Using a direct selective plating procedure, VRE were isolated from 104 of 140 (74.3%) broiler flocks reared in broiler houses previously exposed to avoparcin on conventional and extensive indoor broiler farms. In contrast, only 2 of 22 (9.1%) organic broiler flocks reared on free-range farms with no history of previous exposure to avoparcin were VRE-positive. Furthermore, the occurrence of VRE over time in flocks reared in broiler houses previously exposed to avoparcin was investigated. Results obtained by direct selective plating showed no significant decrease in the proportion of VRE-positive flocks during the study period (1998-2001). This study demonstrated the extensive occurrence of VRE in broiler flocks more than 5 years after the avoparcin ban in Denmark, and indicates that VRE may persist in the absence of the selective pressure exerted by avoparcin. The results differ markedly from previously published Danish surveillance data on VRE in broilers. This may reflect differences in isolation procedures.

Aging↗
PubMed2002

111In-pentetreotide versus bone scintigraphy in the detection of bony metastases of neuroblastoma.

Bone scintigraphy (BS) is widely utilized for the assessment of bone metastases (BMs) of neuroblastoma (NB). Since 111In-pentetreotide scintigraphy (PS) has been used to image NB with high sensitivity, we compared the sensitivity and specificity of PS with that of BS for the detection of BMs of NB. Nine patients with NB underwent both PS and BS for staging and/or restaging of their disease. The sensitivity and specificity of both imaging approaches were compared based on the findings of histopathology, other conventional imaging methods and subsequent clinical follow-up. In five of the nine patients, both PS and BS were negative for BMs. Radiographic bone surveys (RBSs) were also negative in these patients, except in one who showed a suspicious tibial lesion, but a computed tomography-guided biopsy failed to show evidence of disease. These patients remained without clinical evidence of BMs after a median duration of more than 15 months (range, 6-19 months). In three of four remaining patients, both PS and BS were positive for BMs, whilst only PS was positive in one patient. Overall, PS showed a greater number of BMs (30 vs. 7) with greater conspicuity compared with BS. The initial experience comparing BS with PS suggests that PS may provide a better assessment of the extent of BMs of NB, and that it may be useful as an adjunct to BS at institutions in which 131I- or 123I-metaiodobenzylguanidine is not available, particularly if BS is negative. In patients with similarly positive BS, PS might still provide unique prognostic information beyond that provided by BS. Further studies are therefore warranted.

3-Iodobenzylguanidine↗
PubMed2002

Parents' labour market participation as a predictor of children's health and wellbeing: a comparative study in five Nordic countries.

OBJECTIVE: To study the association between parents' labour market participation and children's health and wellbeing. DESIGN: Parent reported data on health and wellbeing among their children from the survey Health and welfare among children and adolescents in the Nordic countries, 1996. A cross sectional study of random samples of children and their families in five Nordic countries (Denmark, Finland, Iceland, Norway, and Sweden). PARTICIPANTS: A total of 10 317 children aged 2-17 years. RESULTS: Children in families with no parents employed in the past six months had higher prevalence of recurrent psychosomatic symptoms (odds ratio 1.67, 95% confidence intervals 1.16 to 2.40), chronic illness (odds ratio 1.35, 95% confidence intervals 1.00 to 1.84), and low wellbeing (odds ratio 1.47, 95% confidence intervals 1.12 to 1.94). Social class, family type, parents' immigrant status, gender and age of the child, respondent, and country were included as confounders. When social class, family type and the parents' immigrant status (one or more born in the Nordic country versus both born elsewhere) were introduced into the model, the odds ratios were reduced but were still statistically significant. Health outcomes and parents' labour market participation were associated in all five countries. CONCLUSIONS: Children in families with no parents employed in the past six months had higher prevalence of ill health and low wellbeing in the five Nordic countries despite differences in employment rates and social benefits.

Adolescent↗
PubMed2002

Comparisons of sampling procedures and time of sampling for the detection of Salmonella in Danish infected chicken flocks raised in floor systems.

Bacteriological follow-up samples were taken from 41 chicken (Gallus gallus) flocks in floor systems, where Salmonella enterica (Salmonella) had been detected either directly in bacteriological samples or indirectly by serological samples. Three types of follow-up samples were compared to each other within each flock: 1) 5 pairs of socks, analysed as 5 samples, 2) 2 pairs of socks, analysed as one sample, and 3) 60 faecal samples, analysed as one pooled sample. Agreement between sampling methods was evaluated by the following statistical tests: 'Kappa', 'The adjusted rand', McNemar's test for marginal symmetry, Proportion of agreement P0, P+, P-, and Odds Ratio. The highest agreement was found between the 2 types of sock sampling, while the lowest agreement was found by comparing 60 faecal samples with 5 pairs of socks. Two pairs of socks analysed as one pool appeared to be just as effective in detecting S. enterica as the 60 faecal samples. In broiler flocks, 5 pairs of socks were used both in the routine samples taken at about 3 weeks of age for the establishment of infection of the flock, and as one of the follow-up samples taken shortly before slaughter age, which means that the only notable differences between the 2 sampling rounds were the age of the broilers and of their litter. S. enterica was detected more frequently in samples from broilers about 3 weeks old, than in similar samples taken from broilers a few days prior to slaughter at ca. 33-40 days of age.

Animals↗
PubMed2001

[Trends in selected biological risk factors of cardiovascular diseases in the Danish MONICA population 1982-1992].

INTRODUCTION: The incidence rate of a first myocardial infarction declined 3-5% annually in the Danish WHO MONICA population in the period from 1982 to 1991. The aim of this study was to investigate whether levels of the most commonly considered biological traits associated with cardiovascular risk have changed in the Danish MONICA population during this period. METHOD: Data from 6,695 men and women of 30, 40, 50 and 60 years of age, examined in the Danish WHO MONICA surveys in 1982-1984, 1986-1987, and 1991-1992, were analysed to estimate temporal trends in body height and weight, blood pressure, and serum total, HDL, and LDL cholesterol, and triglyceride. RESULTS: Body height increased by 0.1% per year and the body mass index by 0.4% per year in women. The diastolic blood pressure increased 0.4% per year in women and 0.6% per year in 60-year-old men. HDL cholesterol declined 0.4% per year. Body mass indices in men, diastolic blood pressures in men < 60 years of age, systolic blood pressures, total and LDL cholesterol and triglyceride did not change. DISCUSSION: The levels of biological risk factors in the Danish WHO MONICA study population did not show trends during the 1980s that contribute to explain the declining incidence of myocardial infarction in the population.

Adult↗
PubMed2001

An epidemiological study of Salmonella enterica serovar 4, 12:b:- in broiler chickens in Denmark.

Epidemiological investigations of isolates of Salmonella enterica serovar 4, 12:b:- were carried out to establish particular molecular markers to assign isolates to a common origin. Plasmid profiling demonstrated that over 50% of 291 isolates, obtained between 1991 and 1996, were plasmid-free. The remaining isolates exhibited a common trend in plasmid content of 105 and 2kb. Although no specific correlation to any particular source within the poultry industry was discernible using plasmid analysis, there were indications of clonality with local divergence. Ribotyping with EcoRI demonstrated limited discriminative potential as 96% of the isolates expressed a common profile. Ribotyping with HindIII failed to further differentiate the isolates. IS200 (PstI) typing and PFGE (NotI and XbaI) afforded some degree of further discrimination with selected isolates. Each technique produced four profiles, but dominant profiles were also apparent. Eighteen variables were selected for multivariate logistic regression analysis in order to identify risk areas associated with broiler flocks within the industry. An increased risk for S. 4, 12:b:- infection was only associated with the feedmills used. Random effects at the house and/or farm level were also found to be statistically significant. Of the 16 feedmills associated with the isolation of 4, 12:b:-, six were deemed to be significant risk factors.

Animal Feed↗