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R Lindqvist

Publications and source records attributed to R Lindqvist.

At least 19 recordsLinked to original sources
PubMed2006

Estimation of Staphylococcus aureus growth parameters from turbidity data: characterization of strain variation and comparison of methods.

Turbidity methods offer possibilities for generating data required for addressing microorganism variability in risk modeling given that the results of these methods correspond to those of viable count methods. The objectives of this study were to identify the best approach for determining growth parameters based on turbidity data and use of a Bioscreen instrument and to characterize variability in growth parameters of 34 Staphylococcus aureus strains of different biotypes isolated from broiler carcasses. Growth parameters were estimated by fitting primary growth models to turbidity growth curves or to detection times of serially diluted cultures either directly or by using an analysis of variance (ANOVA) approach. The maximum specific growth rates in chicken broth at 17 degrees C estimated by time to detection methods were in good agreement with viable count estimates, whereas growth models (exponential and Richards) underestimated growth rates. Time to detection methods were selected for strain characterization. The variation of growth parameters among strains was best described by either the logistic or lognormal distribution, but definitive conclusions require a larger data set. The distribution of the physiological state parameter ranged from 0.01 to 0.92 and was not significantly different from a normal distribution. Strain variability was important, and the coefficient of variation of growth parameters was up to six times larger among strains than within strains. It is suggested to apply a time to detection (ANOVA) approach using turbidity measurements for convenient and accurate estimation of growth parameters. The results emphasize the need to consider implications of strain variability for predictive modeling and risk assessment.

Animals↗
PubMed2006

Microbiological baseline study of broiler chickens at Swedish slaughterhouses.

This 1-year study was conducted to estimate the prevalence and concentrations of pathogenic and indicator bacteria on Swedish broiler chickens. A total of 636 chilled carcasses were collected from 10 slaughterhouses and sent to the National Food Administration for analyses of carcass rinses. No carcasses were positive for Salmonella. Campylobacter, predominantly Campylobacter jejuni, were detected on 15% (by enrichment) or 14% (by direct plating) of the carcasses. With one exception, all samples from late December through April were Campylobacter negative. The 10th and 90th percentiles of Campylobacter numbers per carcasses were 3.0 and 5.0 log CFU, respectively, and the maximum was 7.1 log CFU. Coagulase-positive staphylococci were detected on 68% of the carcasses, with a maximum of 3.5 log CFU/cm2. The 10th and 90th percentiles were 3.4 and 4.4 log CFU/cm2 for total aerobic microorganisms, 1.8 and 3.3 log CFU/cm2 for Enterobacteriaceae, and 2.0 and 3.6 log CFU/cm2 for Escherichia coli. No correlation was found between numbers of any indicator bacteria and numbers of pathogenic bacteria. Subsets of the samples were analyzed for Listeria monocytogenes, Clostridium perfringens, pathogenic Yersinia enterocolitica, and Enterococcus, resulting in prevalence estimates of 29, 18, 9 (as determined by a PCR assay), and 97%, respectively. L. monocytogenes was most common at slaughterhouses with a low prevalence of coagulase-positive staphylococci, and vice versa. These results will improve the ability of researchers to assess the importance of chicken as a source of foodborne pathogens and can serve as a basis for risk management actions.

Abattoirs↗
PubMed2006

Distribution of Campylobacter genotypes on broilers during slaughter.

The highly discriminatory genotyping methods now available for Campylobacter have enabled investigation of the diversity, origin, and route of transmission of this organism. In this study, we investigated the frequency of several genotypes of Campylobacter on chicken carcasses postchilling and on neck skin and cloacal swabs taken at slaughter. Campylobacter isolates recovered with and without enrichment from carcasses were subtyped by macrorestriction profiling. Subtyping 199 Campylobacter isolates from 36 carcasses revealed an average of 1.5 genotypes per carcass. The genotypes present on carcasses were, in most cases, also found in the cloacal samples taken at the beginning of the slaughter process. However, genotypes present on carcasses were, in some cases, not found in the corresponding cloacal samples but in cloacal samples of the preceding slaughter group and, in one case, from the preceding day. The genotypes present in cloacal samples were, with one exception, also found on the corresponding carcasses, indicating that most genotypes survive processing. In most cases, there was a difference of several bands between genotypes present in the same slaughter group, indicating different origins of the isolates rather than the occurrence of a recombination event. However, in two cases, a recombination event could have generated the difference in band patterns seen for two pairs of isolates with nearly identical band patterns, even after cleavage with a second restriction enzyme. The results indicate that individual Campylobacter-positive Swedish chicken carcasses, as well as whole carcass groups, are, in general, contaminated by one or two different genotypes.

Abattoirs↗
PubMed2006

Postchill campylobacter prevalence on broiler carcasses in relation to slaughter group colonization level and chilling system.

Data from an ongoing national surveillance program of Campylobacter prevalence in broiler slaughter groups were related to results from a 1-year baseline study of broiler carcasses postchill. The goals were to establish the relation between Campylobacter prevalence in slaughter groups and on carcasses and to determine the effect of various chilling systems on Campylobacter prevalence. Pooled cloacal and neck skin samples from the surveillance program were analyzed after enrichment. Carcass rinse samples from the baseline study were analyzed after enrichment and by direct plating. Data from both studies were available for 614 carcasses. Direct-plating analyses indicated that the percentages of carcasses positive for Campylobacter jejuni and other Campylobacter spp. in slaughter groups with negative cloacal samples were 2 and 10%, respectively, whereas enrichment analyses indicated prevalences of 2% in both cases. Campylobacter prevalence in slaughter groups with a high degree of intestinal colonization (more than half of the pooled cloacal samples positive) was significantly higher than in slaughter groups with a low degree of colonization (76 to 85% and 30 to 50%, respectively, depending on Campylobacter spp. and analytical method). The prevalence of Campylobacter-positive carcasses postchill was at the same level as the prevalence of carcasses that originated from slaughter groups with positive neck skin samples at four of the six slaughterhouses. Only at one slaughterhouse, with an air-chilling system, was the postchill prevalence (13%) lower than that expected from slaughter group data (23%). The postchill prevalence (43%) was higher than that expected from slaughter group data (33%) at one slaughterhouse with immersion chilling.

Abattoirs↗
PubMed2004

Predicting noncompliant levels of ochratoxin A in cereal grain from Penicillium verrucosum counts.

AIMS: To model the probability of exceeding the European legislative limit of 5 microg ochratoxin A (OTA) per kilogram grain in relation to Penicillium verrucosum levels and storage conditions, and to evaluate the possibilities of using P. verrucosum colony counts for predicting noncompliant OTA levels. METHODS AND RESULTS: Cereal samples were inoculated with P. verrucosum spores and stored for up to 9 months at temperatures and water activities ranging from 10-25 degrees C and aw 0.77-0.95. A logistic regression analysis showed that the probability of exceeding 5 microg OTA kg(-1) grain was related to colony counts of P. verrucosum and water activity. The sensitivity and specificity of various P. verrucosum count thresholds for predicting noncompliant OTA levels were estimated, using data from the storage trial and natural cereal samples. CONCLUSION: The risk of exceeding 5 microg OTA kg(-1) grain increased with increasing levels of P. verrucosum, and with increasing water activities. A threshold of 1000 CFU P. verrucosum per gram grain is suggested to predict whether or not the legislative limit is exceeded. SIGNIFICANCE AND IMPACT OF THE STUDY: This study has provided a tool to evaluate the levels of P. verrucosum in grain in relation to OTA levels. Hence, mycological analyses can be used to identify cereal samples with high risk of containing OTA levels above the legislative limit.

Avena↗
PubMed2004

Home storage temperatures and consumer handling of refrigerated foods in Sweden.

The lack of data on consumer refrigeration temperatures and storage times limits our ability to assess and manage risks associated with microbial hazards. This study addressed these limitations by collecting data on temperatures and storage handling practices of chilled foods. Consumers from 102 households in Uppsala, Sweden, were instructed to purchase seven food items (minced meat, fresh herring fillets, soft cheese, milk, sliced cooked ham, vacuum-packed smoked salmon, and ready-to-eat salad) and to store them using their normal practices. They were interviewed the next day, and food temperatures were measured. In general, there were no significant relations between temperature and characteristics of the respondents (e.g., sex, age, education, age of the refrigerator). Mean storage temperatures ranged from 6.2 degrees C for minced meat to 7.4 degrees C for ready-to-eat salad. Maximum temperatures ranged from 11.3 to 18.2 degrees C. Data were not significantly different from a normal distribution, except for ready-to-eat salad, although distributions other than the normal fitted data better in most cases. Five percent to 20% of the food items were stored at temperatures above 10 degrees C. Most respondents knew the recommended maximum temperature, but less than one fourth claimed to know the temperature in their own refrigerator. Practical considerations usually determined where food was stored. For products with a long shelf life, stated storage times were different for opened and unopened packages. The current situation might be improved if consumers could be persuaded to use a thermometer to keep track of refrigerator temperature.

Adult↗
PubMed2001

Who stops smoking during pregnancy?

BACKGROUND: The proportion of women who stop smoking during pregnancy has varied between 17 and 40% percent in Sweden with a tendency of lower prevalence in recent years. The aim of the present study was to examine the factors that might influence the ability to stop smoking during pregnancy. METHOD: One hundred and two women were interviewed shortly after their first visit to the antenatal clinic and a second time approximately one month after delivery. Two women who had late spontaneous abortions were excluded. The women were asked about background factors, smoking habits of their parents, smoking history and current smoking habits. The carbon monoxide in expiratory air was measured to verify reported smoking habits. RESULTS: Fifty-six of the 100 participating women had stopped smoking before the second interview. Having started smoking at an older age, having no previous children, smoking few cigarettes, a higher level of education, positive support from the partner and having lived with non-smoking parents were all associated with stopping smoking when tested as single factors. Reported smoking habits could be verified. Age, smoking habits of the partner, passive smoking at work, quality of sleep, general perceived health, length of sick-leave or amount of nausea were not correlated to stopping smoking. CONCLUSION: The presence of several factors found to influence stopping smoking during pregnancy, and the tendency for smoking habits to be passed over to the new generation, are reasons for comprehensive and individualized, anti-smoking support.

Age Factors↗
PubMed2001

A one-year study of foodborne illnesses in the municipality of Uppsala, Sweden.

Surveillance was enhanced and a retrospective interview study performed in 1998-99 to determine incidence, causes, and costs of foodborne illnesses in Uppsala, Sweden. Sixty-eight percent of the detected foodborne illness incidents were single cases, and 32% were outbreaks. Most (85%) of the incidents came to the attention of the municipal authorities through telephone calls from affected persons. Calicivirus, Campylobacter spp., and Staphyloccocus aureus were the most common etiological agents; meat, meat products, and mixed dishes were the most implicated food categories. The incidence of foodborne illness was estimated to be 38 cases per 1,000 inhabitants per year. The estimated average costs per illness were 2,164 Swedish Krona (SEK) ($246) to society and 500 SEK ($57) to the patient. The annual cost of foodborne illnesses in Sweden was estimated to be 1,082 million SEK ($123 million).

Adolescent↗
PubMed2000

Quantitative risk assessment for Listeria monocytogenes in smoked or gravad salmon and rainbow trout in Sweden.

The objective of the present work was to develop a quantitative risk assessment model in which the exposure and risk of acquiring listeriosis from consumption of packaged smoked or gravad salmon and rainbow trout were estimated. An Excel spreadsheet model was constructed in which variables were represented by distributions based on surveys of L. monocytogenes in these food products, and on demographic and consumption data. Growth or inactivation was not included in the model. The model was run through Monte Carlo simulations using the @Risk software (Palisade Corporation). The probability of illness per serving was calculated using two dose-response models from the literature. The first was an exponential model in which the species specific constant R, that helps define the dose-response curve, previously has been estimated to be 1.18 x 10(-10) based on German data (GR). In this study, R was estimated to 5.6 x 10(-10) based on Swedish data. The second model was a flexible Weibull-Gamma model (WG), with different coefficients for high- and low-risk groups. The exponential model (GR), although conservative and generally overestimating the risk, still predicted a lower probability of illness than the WG-model. The estimated mean risk per serving was 2.8 x 10(-5) (GR, high-risk group), 2.0 x 10(-3) (WG, low-risk group) and 0.016 (WG, high-risk group), respectively. The average number of reported listeriosis cases in Sweden is 37 per year. In comparison, the mean number of annual cases predicted by the risk assessment model was 168 (range 47 to 2800, GR, high-risk group), and 95 000 (range 34 000 to 1.6 x 10(6), WG high-risk group), respectively. If 1 to 10% (uniform distribution) of strains, instead of all, were considered virulent, the mean number of predicted cases would decrease to nine (GR) and 5200 (WG), respectively. The mean annual cumulative individual risk in the high-risk group based on a monthly exposure was estimated to be 4.0 x 10(-4) (range 8.0 x 10(-8) to 5.4 x 10(-3), GR). This risk increased to 1.5 x 10(-3) (range 1.7 x 10(-5) to 9.2 x 10(-3), GR) based on a weekly exposure. The risk assessment model was most sensitive to the input distribution describing the level of contamination and to a lesser degree on the prevalence of L. monocytogenes, the proportion of virulent strains, and serving sizes. A lack of data on the prevalence and concentration of L. monocytogenes in these products, dose-response data and quantitative information on the proportion of virulent strains were identified.

Animals↗
PubMed2000

Coping strategies and health-related quality of life among spouses of continuous ambulatory peritoneal dialysis, haemodialysis, and transplant patients.

In the study reported here 55 spouses of patients living with end-stage renal disease (ESRD) were investigated with respect to coping strategies and health-related quality of life. Findings from the study were compared to two random samples of the Swedish general population (n = 454, and n = 1200). The study design was correlational and comparative. Coping was measured by the Jalowiec Coping Scale, and quality of life (QoL) by the Swedish Health-Related Quality of Life Survey (SWED-QUAL). Data were analysed using a number of statistical tests including Pearson's product moment correlations, Student's t-test and two way ANOVAs. The combined sample of spouses used significantly more optimistic and palliative coping than the general population, but less confrontative, self-reliant, evasive and emotive coping. In the study fatalistic, evasive and emotive coping was associated with low perceived efficiency in handling various aspects of the partners' situation. The male spouses used significantly less optimistic, supportive and palliative coping than did the female spouses. The spouses of transplant patients had better overall quality of life than the continuous ambulatory peritoneal dialysis and haemodialysis spouse groups, most likely due to the lower age of the former group. The study findings suggest that emotive, evasive and fatalistic coping are less than optimal ways to deal with problems occasioned by the partner's treatment.

Adaptation, Psychological↗
PubMed2000

A summary of reported foodborne disease incidents in Sweden, 1992 to 1997.

Reports of foodborne disease incidents in Sweden from 1992 to 1997 are summarized. The results are based on reports from the municipal environmental and public health authorities to the National Food Administration and from medical authorities to the Swedish Institute for Infectious Diseases Control. A total of 555 incidents, of which 84% were outbreaks, were reported, involving 11,076 ill people. In 66% of the incidents, no disease agent was determined. Bacterial agents were implicated in 25% and viruses in 8% of the incidents. Calicivirus was the most reported agent both in terms of incidents and cases. Mixed dishes was the food category most often implicated in outbreaks, and smorgasbord and casserole or stews were the subcategories that caused the most cases. The place of consumption was unknown in 8% of the incidents. In about 60% of the incidents, the implicated food was consumed in commercial food establishments; in approximately 20% of incidents, it was consumed at home. The average annual incidence of reported foodborne disease in Sweden was estimated to be 21 cases per 100,000. The average annual incidence of reported foodborne salmonellosis and campylobacteriosis was estimated to be 2.0 and 0.6 cases per 100,000, respectively. The awareness and motivation to report foodborne diseases need to be improved, but additional sources of information are needed to counteract some of the limitations of reporting discussed in this work.

Caliciviridae↗
PubMed2000

Perceived consequences of being a renal failure patient.

This study describes the perceived consequences of illness and treatment among end stage renal disease (ESRD) patients. A qualitative, explorative-descriptive design was used, which included continuous ambulatory peritoneal dialysis (CAPD) (n = 26), hemodialysis (HD) (n = 30), and transplantation (n = 30) patients. Data collection was performed using unstructured interviews, mostly in the patients' homes. All interviews were tape-recorded with permission from the informants, transcribed verbatim, and analyzed by content analysis. An overall theme was identified, "Wishes for independence and normality." Four main categories emerged: "Wish for normality," "Wish to manage one's own life," "Deprivation of one's normal life," and "Concerns." Interview statements were classified in 11 subcategories: live as usual, keep up appearances, social comparison, hope/fulfilled dreams, freedom/lack of freedom, control/lack of control, losses, dependence on others, physical problems, disgusted with oneself, and broodings. The perceived consequences of being an ESRD patient are multidimensional and involve several aspects of everyday life. It is important for nurses to appreciate the patient's view of illness as well as the patient's perceived stressors and expectations. It may help to direct the focus of nursing assessment in planning and implementing nursing care.

Adult↗
PubMed2000

Coping strategies and styles assessed by the Jalowiec Coping Scale in a random sample of the Swedish population.

A random sample of the Swedish general population (n = 1,200), age range 18-80 years, was studied with regard to coping strategies and styles used for handling stressful situations. The total response rate was 65% (n = 519), and coping was assessed by the Jalowiec Coping Scale (JCS). The three most frequently used coping styles were the confrontative, the optimistic and the self-reliant. The three least used styles were the emotive, the supportant and the palliative. There were few differences between the age groups for the total material or for each gender separately. Young (18-29 years) and middle-aged (30-59 years) groups used confrontative and emotive styles significantly more than did the elderly (60-80 years) group. Young and middle-aged women used significantly more optimistic, evasive, emotive and supportant coping than did elderly women. All subscales except the self-reliant showed significant gender differences, with women reporting more frequent use than men. Ethnicity is a major determinant of the use of the emotionally-oriented coping styles. Those of Swedish origin used less of these styles than did those of non-Swedish origin. The results illustrate the importance of using different norm values for the JCS for groups differering in these demographic variables.

Adaptation, Psychological↗
PubMed1999

Psychometric assessment of the Life Satisfaction Questionnaire (LSQ) and a comparison of a randomised sample of Swedish women and those suffering from breast cancer.

In a previous study, the Life Satisfaction Questionnaire (LSQ) was developed especially for women with breast cancer. The aim of the present study was to assess the psychometric properties of the LSQ in a randomized sample of Swedish women and to compare the perceived quality of life with that of women suffering from breast cancer. Another aim was to relate the result to educational background. A total of 257 women aged 20-80, randomly selected from the Swedish population register, answered the LSQ. The result was compared with that from 362 women aged 27-78 suffering from breast cancer. The construct validity was calculated by a principal component analysis, and the reliability by Cronbach alpha-coefficients. It was concluded that the LSQ has acceptable validity and reliability. The result also showed that the women with breast cancer rated their perceived quality of life higher than women in general with respect to the quality of personal relations and the quality of daily activities, but lower for physical symptoms. In the comparison with respect to educational background, women with university education rated their quality of life higher than women with other types of education. The testing of the LSQ will continue.

Adult↗
PubMed1999

Detection of Shigella spp. in food with a nested PCR method-sensitivity and performance compared with a conventional culture method.

A nested PCR method was developed and its performance evaluated by detection of Shigella flexneri in food. The nested PCR amplifies sequences within an invasion-associated locus (ial) on the invasion plasmid specific for Shigella and enteroinvasive Eschrichia coli (EIEC). The nested PCR detected Sh. flexneri in lettuce inoculated with 2, 20 and 200 cfu g-1 after 1, 7 and 18 d of storage, respectively. In comparison, a culture method (NMKL no. 151) detected 10(5) cfu g-1 after 1 but not after 7 d of storage. The presence of inhibitors in blue cheese and shrimps reduced the sensitivity of the PCR assay. To overcome this inhibition, a sample preparation step based on buoyant density centrifugation was developed. This treatment resulted in a successful recovery of Sh. flexneri in lettuce, milk, shrimp and blue cheese inoculated with 10 cfu g-1. The proposed method, which includes a combination of enrichment, buoyant density centrifugation and a nested PCR, can be completed in less than two working days.

Centrifugation, Density Gradient↗
PubMed1999

Vocational rehabilitation of the socially disadvantaged long-term sick: inter-organizational co-operation between welfare state agencies.

Vocational rehabilitation targeted to the socially disadvantaged long-term sick requires that the client keep in touch with a number of welfare state agencies, all of which have different regulations, conflicting goals and various types of benefits. This is an arduous and time-consuming task for clients with medical, social and labour market problems. Many of these clients run the risk of ending up in a no-man's land or being endlessly circulated between agencies because their problems do not correspond to the profile of the typical client. Both government and welfare workers see institutional co-operation between welfare state agencies as the remedy to such problems. This article, which is based on interviews with participants in fourteen cooperating projects, focuses on difficulties and opportunities experienced in such co-operation. It is concluded that such cooperation, when initiated in local settings and supported by local players, is a way of rejuvenating the existing Swedish model.

Chronic Disease↗
PubMed1998

Coping strategies and quality of life among patients on continuous ambulatory peritoneal dialysis (CAPD).

The present study describes CAPD patients' coping strategies and quality of life. A descriptive-comparative design was chosen and a consecutive series of patients (n = 26) was included. Data collection was performed through questionnaire and interview. Coping was measured by the Jalowiec Coping Scale and quality of life by the Swedish Health-Related Quality of Life Survey (SWED-QUAL). The main results show that an optimistic coping style was the most widely used by both men and women and this style was also considered to be the most effective in terms of dealing with stressful treatment aspects. Significantly more men than women found emotive coping to be less effective. Compared to a sample from the general population, CAPD patients had lower values on all SWED-QUAL sub-scales except those that tapped family functioning and emotional health. In general, women evidenced a more negative perception of their health than did men. With respect to emotional well-being/negative aspect, the CAPD patients achieved higher scores than the general population. The findings suggest targets for nurse practitioners' provision of support and information and in assisting patients to better utilize adequate coping methods to enhance their quality of life.

Adaptation, Psychological↗