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Anders Thelin

Publications and source records attributed to Anders Thelin.

13 recordsLinked to original sources
PubMed2006

Unexpected high prevalence of IgG-antibodies to hepatitis E virus in Swedish pig farmers and controls.

Hepatitis E virus (HEV) infections are responsible for large waterborne outbreaks in developing countries. Sporadic cases in the developed world are mainly imported via immigrants and travellers from endemic areas. HEV has been suggested to be a zoonotic infection where pigs may be an important reservoir for the disease and specific swine strains of HEV have been identified which can infect also humans. The aim of this study was to analyse if Swedish pig farmers are more exposed to HEV than persons with other occupations. A total of 115 male pig farmers aged 40-60 y and 108 age- and geographically- matched control subjects were tested for IgG anti-HEV antibodies. No statistical difference in anti-HEV prevalence was noted between pig farmers (13.0%) and control subjects (9.3%). The prevalence of anti-HEV antibodies in the pig farmers and controls was higher than that previously reported among other populations in Europe (<1-9%). Further studies are needed to elucidate the routes for infection of indigenous HEV and if sub-clinical infections with pig associated HEV strains occur in Sweden.

Adult↗
PubMed2005

Gene expression analysis suggests that EBF-1 and PPARgamma2 induce adipogenesis of NIH-3T3 cells with similar efficiency and kinetics.

Differentiation of multipotent mesenchymal stem cells into lipid-accumulating adipocytes is a physiological process induced by transcription factors in combination with hormonal stimulation. We have used Affymetrix microarrays to compare the adipogenic differentiation pathways of NIH-3T3 fibroblasts induced to undergo in vitro differentiation by ectopic expression of early B cell factor (EBF)-1 or peroxisome proliferator-activated receptor (PPAR)gamma2. These experiments revealed that commitment to the adipogenic pathway in the NIH-3T3 cells was not reflected in gene expression until 4 days after induction of differentiation. Furthermore, gene expression patterns at the earlier time points after stimulation indicated that EBF-1 and PPARgamma2 induced different sets of genes, while the similarities increased upon differentiation, and that several genes linked to adipocyte differentiation were also transiently induced in the vector-transduced cells. These data suggest that the initial activation of genes associated with adipocyte development is independent of commitment to the adipogenic pathway and that EBF-1 and PPARgamma2 induce adipocyte differentiation with comparable kinetics and efficiency.

3T3-L1 Cells↗
PubMed2005

Low back pain comorbidity among male farmers and rural referents: a population-based study.

Farmers report more low back pain (LBP) than rural referents. We have previously demonstrated that the difference in reporting rate cannot be fully explained by known risk factors such as physical work exposures, psychosocial factors and lifestyle. Other etiological factors must be involved. In this cross-sectional population-based study, we investigate LBP comorbidity in terms of coexistent symptoms. A total of 1,013 male farmers, 40-60 years old, and 769 matched rural referents participated in an extensive health survey. Information on causes of primary health care and hospital admissions, symptoms, lifestyle factors, physical work exposures and psychosocial factors were gathered through standardized interviews and questionnaires. In the combined farmer-referent group, the prevalence of LBP was associated with musculoskeletal symptoms other than LBP, chest discomfort, dyspepsia, symptoms from eyes, nose and throat mucous membranes, skin problems, work-related fever attacks, and primary care appointments due to digestive disorders. The associations were independent of age, educational level, smoking habits, body mass index, physical work exposures and psychosocial factors. Presence of both respiratory and digestive disorders doubled the LBP prevalence. Significant associations between LBP and digestive and respiratory disorders were revealed, indicating that LBP and these disease entities may have etiological factors in common.

Agricultural Workers' Diseases↗
PubMed2004

Role of ADAMTS-1 in atherosclerosis: remodeling of carotid artery, immunohistochemistry, and proteolysis of versican.

OBJECTIVE: We investigated the potential role of ADAMTS-1 (a disintegrin and metalloprotease with thrombospondin motif type I) in atherogenesis. METHODS AND RESULTS: ADAMTS-1 is expressed at the highest levels in the aorta when compared with other human tissues examined. Immunolocalization studies in human aorta and coronary artery indicate that ADAMTS-1 expression is mainly seen at low levels in the medial layer, but upregulated in the intima when plaque is present. We found that ADAMTS-1 mRNA levels are significantly higher in proliferating/migrating cultured primary aortic vascular smooth muscle cells (VSMCs) compared with resting/confluent cells. Using the mouse carotid artery flow cessation model, we show that there are differences in vessel remodeling in ADAMTS-1 transgenic/apoE-deficient mice compared with apoE deficiency alone, particularly a significant increase in intimal hyperplasia. We show that ADAMTS-1 can cleave the large versican containing proteoglycan population purified from cultured human aortic VSMCs. Finally, using versican peptide substrates, we show data suggesting that ADAMTS-1 cleaves versican at multiple sites. CONCLUSIONS: We hypothesize that ADAMTS-1 may promote atherogenesis by cleaving extracellular matrix proteins such as versican and promoting VSMC migration.

ADAM Proteins↗
PubMed2004

Is there an increased risk of knee osteoarthritis among farmers? A population-based case-control study.

OBJECTIVES: Occupational workload is generally considered a to be contributing cause in the development of knee osteoarthritis, in addition to well-known risk factors such as age, female gender, excess weight and previous knee injuries. Farmers have an increased risk of developing hip osteoarthritis, but it is uncertain if farming is influencing the occurrence of knee osteoarthritis. The aim of this population-based case-control study was to investigate the risk of radiographically verified femorotibial osteoarthritis among farmers and those in some other physically demanding occupations. METHODS: A mailed questionnaire inquiring about previous occupations was answered by 778 subjects having X-ray verified osteoarthritis in the femorotibial joint and 695 matched controls. The reply frequency was 89%. Mean age of the participants was 63 years, 43% were male and 57% female. The relationship between knee osteoarthritis and occupation was analysed by multiple logistic regression, with adjustment for a number of variables. RESULTS: Men who had worked for 11-30 years in the building and construction industry had a 3.7-times (95% CI 1.2-11.3) increased risk of knee osteoarthritis. Farm work was not related to an increased risk for men. However, women who had worked for 11-30 years in farming tended to have an increased risk (OR 2.1, 95% CI 1.0-4.5). Forestry, letter-carrying (postal), cleaning and healthcare work was not related to knee osteoarthritis. Excess weight, heredity and previous knee injuries were strong risk factors, whereas smoking showed a negative relationship to knee osteoarthritis. CONCLUSION: Work in building and construction occupations, but not in farming, was associated with an increased risk of knee osteoarthritis.

Adult↗
PubMed2004

A comparison of oligonucleotide and cDNA-based microarray systems.

Large-scale public data mining will become more common as public release of microarray data sets becomes a corequisite for publication. Therefore, there is an urgent need to clarify whether data from different microarray platforms are comparable. To assess the compatibility of microarray data, results were compared from the two main types of high-throughput microarray expression technologies, namely, an oligonucleotide-based and a cDNA-based platform, using RNA obtained from complex tissue (human colonic mucosa) of five individuals. From 715 sequence-verified genes represented on both platforms, 64% of the genes matched in "present" or "absent" calls made by both platforms. Calls were influenced by spurious signals caused by Alu repeats in cDNA clones, clone annotation errors, or matched probes that were designed to different regions of the gene; however, these factors could not completely account for the level of call discordance observed. Expression levels in sequence-verified, platform-overlapping genes were not related, as demonstrated by weakly positive rank order correlation. This study demonstrates that there is only moderate overlap in the results from the two array systems. This fact should be carefully considered when performing large-scale analyses on data originating from different microarray platforms.

Aged↗
PubMed2004

Osteoarthritis of the hip joint and farm work.

BACKGROUND: Different types of farming and farm work were studied in relation to the occurrence of osteoarthritis of the hip joint in a cohort of farmers. METHODS: A group of 427 farmers with hip joint osteoarthritis were identified together with a matched control group of farmers without hip or knee problems. All were invited to an interview and physical examination. After a dropout of 10%, and removing those who had had predisposing diseases or trauma, the observations for 369 pairs were available for analyses. RESULTS: Farmers with larger dairy and swine confinement operations (sows) had an increased risk of acquiring osteoarthritis of the hip. In a logistic regression multivariate model, those who milked more than 40 cows daily had an increase in risk (OR = 4.5, 95% CI 1.9-11.0) in relation to those who did not work in dairy production. Those who had worked more than 5 hr daily in animal barns over a long period of time also had an increase in risk (OR = 13.3, 95% CI 1.2-145.0) in relation to those who did not work with animals. In another model, those who had large farm areas (>100 ha) had a significantly decreased risk (OR = 0.14, 95% CI 0.05-0.43) in relation to those who had smaller farm areas. CONCLUSIONS: Farmers operating farms with large plant production area and few animal contacts had a significantly lower risk of incurring osteoarthritis of the hip than did farmers in general. The presence of animal production showed a significant positive relationship to the risk of developing hip joint osteoarthritis. Am. J. Ind. Med. 45:202-209, 2004.

Adult↗
PubMed2004

Psychosocial factors and low back pain, consultations, and sick leave among farmers and rural referents: a population-based study.

Farmers have more low back pain (LBP) than nonfarmers. In a previous report, we found that differences between farmers and nonfarmers in physical work exposure did not explain the LBP differences. In this report, we tested the hypothesis that psychosocial factors might explain the differences in LBP reporting, medical consultation, and sick leave. A cross-sectional population-based survey of 1,013 middle-aged farmers and 769 matched referents was performed. Data on LBP, consultations, and sick leave during lifetime was obtained along with information on psychosocial, social network, and lifestyle variables. Several of the psychosocial variables were associated with LBP but the difference in LBP prevalence between farmers and nonfarmers could be explained only marginally. Farmers and self-employed referents tended to have lower odds of sick leave because of LBP than employed referents after adjustment for psychosocial factors.

Agricultural Workers' Diseases↗
PubMed2004

Vascular gene expression in atherosclerotic plaque-prone regions analyzed by representational difference analysis.

OBJECTIVES: Atherosclerotic plaques are known to develop and progress where the endothelium is subjected to turbulent blood flow. We have applied cDNA representational difference analysis (RDA) to study vascular gene expression in mouse aorta in a model for atherosclerosis. METHODS: Gene expression profiles were investigated in plaque-prone and plaque-resistant localizations in the ascending aorta and arch in 8-week-old ApoE-/- and LDLR-/- mice. Total RNA was extracted and two rounds of subtraction were performed; the difference products were characterized in detail by shotgun cloning and analysis of more than 2,700 gene sequences. RESULTS: The identified differentially expressed gene sequences include both genes with known involvement in vascular gene expression and genes previously not implicated in vascular processes. For example, CD36 and caveolin, previously reported for their participation in the progression of atherosclerosis, were found to have an increased expression in vessel localizations thought to be especially susceptible to plaque formation. CONCLUSIONS: This report provides new in vivo information of expressed genes that can be useful for further investigations of the molecular mechanisms in focal localization of atherosclerosis.

Animals↗
PubMed2003

Shotgun sequencing and microarray analysis of RDA transcripts.

Monitoring of differential gene expression is an important step towards understanding of gene function. We describe a comparison of the representational difference analysis (RDA) subtraction process with corresponding microarray analysis. The subtraction steps are followed in a quantitative manner using a shotgun cloning and sequencing procedure that includes over 1900 gene sequences. In parallel, the enriched transcripts are spotted onto microarrays facilitating large scale hybridization analysis of the representations and the difference products. We show by the shotgun procedure that there is a high diversity of gene fragments represented in the iterative RDA products (92-67% singletons) with a low number of shared sequences (<9%) between subsequent subtraction cycles. A non redundant set of 1141 RDA clones were immobilized on glass slides and the majority of these clones (97%) gave repeated good fluorescent signals in a subsequent hybridization of the labelled and amplified original cDNA. We observed only a low number of false positives (<2%) and a more than twofold differential expression for 32% (363) of the immobilized RDA clones. In conclusion, we show that by random sequencing of the difference products we obtained an accurate transcript profile of the individual steps and that large-scale confirmation of the obtained transcripts can be achieved by microarray analysis.

Cell Line↗
PubMed2003

The impact of physical work exposure on musculoskeletal symptoms among farmers and rural non-farmers.

In order to evaluate the impact of physical work exposure on differences in musculoskeletal symptom reported among Swedish farmers and referents, a cross-sectional, population-based cohort study was performed. Male farmers (N = 1221) and matched non-farmers (N = 1130) were invited to take part a survey in which 76 % participated. The analyses were based on 657 matched pairs. Lifetime incidence of musculoskeletal symptoms, information on work exposure, physical workload and leisure time physical activity were assessed by questionnaire and structured interview. Physical work capacity and muscle strength were measured. Farmers reported more low back and hip problems than the referents. After adjustment for the influence of work exposure factors, farmers still had a significant excess rate of low back and hip symptoms compared to the referents, and a significantly lower rate of neck and shoulder problems. In conclusion, work exposure explained some but not all of the farmer-referent differences in musculoskeletal symptom rates.

Agricultural Workers' Diseases↗
PubMedDate not supplied

Musculoskeletal symptoms among farmers and non-farmers: a population-based study.

Farming has been considered a high-risk occupation for musculoskeletal disorders. However, documentation of the increased risk is weak except for hip osteoarthritis. 1,013 full-time farmers in nine Swedish municipalities and 769 non-farmers (referents), matched for age, sex, and residential area, participated in the study. Information about medical history, consultations, and sick leave for musculoskeletal disorders was obtained by questionnaire and interview. The farmers reported significantly more symptoms affecting the hands and forearms, low back, and hips than did the non-farmers, and a non-significant trend in the same direction was found for symptoms from the neck, shoulders, and knees. However, the farmers did not seek medical advice more often than the referents, and they reported significantly less sick leave for these problems. Thus, farmers appear to have more musculoskeletal symptoms than do non-farmers.

Adult↗