| 1. |
- Enlund, Karolina Brunius, et al.
(författare)
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Dental home care in dogs-a questionnaire study among Swedish dog owners, veterinarians and veterinary nurses
- 2020
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Ingår i: BMC Veterinary Research. - : Springer Science and Business Media LLC. - 1746-6148. ; 16:1
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Tidskriftsartikel (refereegranskat)abstract
- Background Periodontal disease remains one of the dog's most common health issues, even though it is largely preventable by tooth brushing. Implementation of daily tooth brushing would not only improve animal welfare, but also reduce veterinary costs for the owner. There is a paucity of studies investigating attitudes, opinions and practices of dog owners, veterinarians, and veterinary nurses regarding preventative dental home care in dogs. The objective of this study was to investigate these parameters in Sweden, thereby providing a basis for improved prophylactic strategies. Methods Validated questionnaire surveys were distributed to all Swedish dog owners (n = 209,263), veterinarians (n = 3657) and veterinary nurses (n = 1650) with e-mail addresses in the national registry. The response rates were 32% for dog owners and veterinarians, and 38% for veterinary nurses. The survey questions concerned attitudes, opinions and practices regarding dental home care, including whether dog owners received information concerning dental home care or not, and if this information resulted in implementation. Results Attitudes, opinions and practices regarding dental home care are presented for Swedish dog owners, veterinarians, and veterinary nurses. A fundamental finding was that the absolute majority of Swedish dog owners do not perform adequate prophylactic dental home care. Considerable discrepancies were identified in the opinions of veterinary health practitioners and dog owners regarding attitudes towards dental home care and conveying of information. Several areas for improvement in the communication between dog owners and veterinary health practitioners concerning dental home care were identified. Conclusion Our results illustrates the need for validated methods to increase dog owner compliance with dental home care recommendations. We also see a need of further education, regarding canine dental home care, among veterinarians, veterinary nurses, and dog owners. The results from this unique study constitute an important foundation for future development of prophylactic strategies, with the ultimate goal to improve dental health, and thereby animal welfare, in dogs.
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| 2. |
- Enlund, Karolina Brunius, et al.
(författare)
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Development and validation of two questionnaires: Dental home care and dental health in Swedish dogs
- 2019
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203 .- 1932-6203. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Background: Dental disease is one of the most common health problems in dogs. However, no studies have investigated the attitudes, opinions and practices of dog owners, veterinarians and veterinary nurses regarding dental health and preventative dental home care in dogs. The objective of this study was therefore to develop and validate questionnaires for this purpose, in accordance with survey methodology guidelines. Methods: Questionnaire items were determined based on the authors' academic knowledge and clinical experience, and modified throughout the validation process. Several measures were taken to reduce sampling, coverage, measurement and non-response errors. Content validity was assessed by Subject-Matter Experts (SME) and cognitive interviews were conducted in accordance with the “think-aloud protocol”. Non-response analysis was performed using several methods. Results: Constructs were identified using exploratory factor analysis and two predefined constructs from the dog owner questionnaire were confirmed “Dog owners' attitudes towards brushing their dog's teeth” (Cronbach's α = 0.86) and “Dog owners' assessment of their dog's dental health” (α = 0.76). Additionally, exploratory factor analysis identified three potential constructs. In the veterinary health practitioner questionnaire, two constructs were identified: “Veterinary health practitioners' attitudes towards dental chews and dental feed” (α = 0.78) and “Veterinary health practitioners' attitudes and opinions on dental problems and dental cleaning” (α = 0.73). Non-response analysis showed a higher proportion of women in the sample of dog owners and veterinarians compared to the target populations. Veterinarians in the sample were also younger. In contrast, gender and age distributions in veterinary nurses did not differ between sample and target. Conclusion: The validation presented in this work showed that the developed questionnaires could be used as accurate and reliable tools for measuring attitudes and practices regarding dental home care in dogs among Swedish dog owners, veterinarians and veterinary nurses.
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| 3. |
- Enlund, Karolina Brunius, et al.
(författare)
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Dog Owners' Perspectives on Canine Dental Health : A Questionnaire Study in Sweden
- 2020
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Ingår i: Frontiers in Veterinary Science. - : Frontiers Media SA. - 2297-1769. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- Periodontal disease is one of the most common diseases affecting dogs, with a reported prevalence of at least 80% in dogs over 3 years of age. However, there is a lack of studies regarding dog owners' assessment of their dog's dental health, and whether they perceive clinical signs often associated with periodontal disease, i.e., dental calculus, halitosis or mobile or lost teeth. A validated questionnaire survey was distributed to all Swedish dog owners with email addresses in the national registry (n = 209,263). The response rate was 32%. The survey questions concerned opinions and practices regarding canine dental health, including assessment of dental health parameters and dog owners' ability to examine their dog's mouth. A construct (α = 0.76) was used to investigate dog owners' assessed symptoms of their dog's dental health in relation to background factors. Half of the respondents rated their dog's dental health as very good. However, one in four dog owners experienced difficulties when inspecting the dog's teeth. The most common reason for this difficulty was stated to be an uncooperative dog. Almost half of the dog owners reported halitosis to some degree in their dog, and almost four in ten owners reported dental calculus. One in eight dogs had been previously anesthetized for dental cleaning, and one in 12 dogs had experienced problems with gum disease, according to the owners. Owners' assessment varied significantly with the dog's age, weight, breed, breed group, sex, and concurrent disease. Owner-related factors that influenced the assessment of the dog's dental health were age, gender, education, county (urban/rural), and whether they were breeders or not. Dog owners with smaller dogs, older dogs and certain breeds predisposed to periodontal disease assessed their dog's dental health as worse than their counterparts, which is in agreement with previously reported higher prevalence of dental disease in these groups. This indicates that dog owners are able to perform relative assessment of their dog's dental health status. Our results also highlight the need for routine professional assessment of periodontal health, as well as education of dog owners and training of dogs to accept dental care procedures.
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| 4. |
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| 5. |
- Enlund, Karolina Brunius, et al.
(författare)
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Professional dental cleaning in dogs: clinical routines among Swedish veterinarians and veterinary nurses
- 2020
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Ingår i: Acta Veterinaria Scandinavica. - : Springer Science and Business Media LLC. - 1751-0147 .- 0044-605X. ; 62:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Dental disease is very common in dogs and veterinary professional dental cleaning and examination, together with daily dental home care, is the foundation for good dental health. To our knowledge, no previous study has investigated professional dental cleaning routines in small animal veterinary practice. A validated questionnaire survey was distributed to all veterinarians and veterinary nurses with registered e-mail addresses in the Swedish national registry (veterinarians; n = 3657, veterinary nurses; n = 1650). Response rates were 32% for veterinarians (V) and 38% for veterinary nurses (VN). Results: In total, 73% (V)/96% (VN) of respondents reported that professional dental cleaning was performed at their work place under general anesthesia, and 27% (V)/18% (VN) that dental cleaning was performed under sedation. Of the respondents, 43% (V)/96% (VN) considered regular dental cleaning under general anesthesia fairly or very important, and 49% (V)/47% (VN) stated that it was sometimes important for good dental health in dogs. A majority of respondents, 84% (V)/97% (VN), reported that dental extractions were performed at their clinic, and 72% (V)/90% (VN) had access to dental radiography equipment. Conclusion: A majority of Swedish veterinarians and veterinary nurses perform professional dental cleaning under general anesthesia with access to dental radiography equipment, in accordance with national and international recommendations. However, a considerable proportion of professional dental cleanings were performed under sedation only, and extractions performed without access to dental radiography equipment were common, suggesting several areas of improvement in the routines in Swedish veterinary clinics and hospitals. Our results clearly indicate the need for improved educational efforts to increase the awareness among veterinary health professionals regarding guidelines and official recommendations in canine dental care.
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| 6. |
- Almanza-Aguilera, Enrique, et al.
(författare)
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Impact in Plasma Metabolome as Effect of Lifestyle Intervention for Weight-Loss Reveals Metabolic Benefits in Metabolically Healthy Obese Women
- 2018
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Ingår i: Journal of Proteome Research. - : American Chemical Society (ACS). - 1535-3907 .- 1535-3893. ; 17:8, s. 2600-2610
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Tidskriftsartikel (refereegranskat)abstract
- Little is known regarding metabolic benefits of weight loss (WL) on the metabolically healthy obese (MHO) patients. We aimed to examine the impact of a lifestyle weight loss (LWL) treatment on the plasma metabolomic profile in MHO individuals. Plasma samples from 57 MHO women allocated to an intensive LWL treatment group (TG, hypocaloric Mediterranean diet and regular physical activity, n = 30) or to a control group (CG, general recommendations of a healthy diet and physical activity, n = 27) were analyzed using an untargeted1H NMR metabolomics approach at baseline, after 3 months (intervention), and 12 months (follow-up). The impact of the LWL intervention on plasma metabolome was statistically significant at 3 months but not at follow-up and included higher levels of formate and phosphocreatine and lower levels of LDL/VLDL (signals) and trimethylamine in the TG. These metabolites were also correlated with WL. Higher myo-inositol, methylguanidine, and 3-hydroxybutyrate, and lower proline, were also found in the TG; higher levels of hippurate and asparagine, and lower levels of 2-hydroxybutyrate and creatine, were associated with WL. The current findings suggest that an intensive LWL treatment, and the consequent WL, leads to an improved plasma metabolic profile in MHO women through its impact on energy, amino acid, lipoprotein, and microbial metabolism.
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| 7. |
- Alvarsson Jan-Åke, Agüero Oscar, Bretschneider Peter, Brunius Staffan, Gumucio Juan Carlos, Gurt Carl-Johan, Hultkrantz Åke, Isacsson Sven-Erik, Johnsson Mick, Kurkiala Mikael, Liljefors-Persson Bodil, Perruchon Marie & Århem Kaj
(författare)
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Amerikas indiankulturer
- 1997
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Bok (övrigt vetenskapligt/konstnärligt)
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| 8. |
- Andersson, Annica, et al.
(författare)
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Paths to a sustainable food sector guided by LCA – exemplified by pork production
- 2014
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- To describe a more sustainable food sector, a supply chain approach is needed. Changing supply chains inevitably means that a range of attributes of the product and its system will change. This project will take on this challenge and deliver detailed descriptions of supply chains of six commodities from a Swedish region in 2012; Milk, cheese, beef, pork, chicken and bread. The set-up of the project was that experts on production along the supply chain design environmentally improved systems. The next step was to challenge the improvements considering their possible consequences on products and systems from different perspectives: food safety, sensory qualities, animal welfare, and consumer appreciation and (only for primary production) costs. The final supply chains were quantified by life cycle assessment (LCA), and they were again assessed from the perspectives mentioned above. Results will be generated during August 2014 and comprise both single-product LCA and region-wide impacts of the future scenarios.
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| 9. |
- Andersson, Kristina, et al.
(författare)
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Early vaccination with Improvac® - effects on performance and behaviour of male pigs
- 2012
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Ingår i: Animal. - 1751-7311 .- 1751-732X. ; 6, s. 87-95
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to investigate the effect of giving a two-dose regimen of gonadotropin-releasing hormone vaccine, Improvac (R) (Pfizer Ltd), earlier than currently recommended, on performance and behaviour of growing/finishing pigs. Cross-bred male pigs (n = 5192) were randomly allocated, within a litter, into four groups at birth: one group of pigs surgically castrated without anaesthesia before one week of age, a second group of early vaccinated pigs given Improvac at 10 and 14 weeks of age, a third group of standard vaccinated pigs given Improvac at 16 and 20 weeks of age, so that the second vaccination was given 4 to 6 weeks before slaughter as recommended by the manufacturer, and a fourth group of entire male pigs. The experiment started when the pigs were 12 weeks old and lasted until 25 weeks of age, when the pigs were slaughtered. The pigs were fed restrictedly. Daily weight gain and feed conversion during the entire raising period did not differ significantly between groups. Estimated lean meat content of early vaccinated and surgically castrated pigs was lower when compared with entire male pigs, whereas standard vaccinated pigs did not differ from entire males. Dressing percentage was higher in early vaccinated and surgically castrated pigs than in standard vaccinated and entire male pigs, partly because of lower size and weight of reproductive organs. For both groups of vaccinated pigs, both problematic and non-problematic behaviours decreased after their second injection, from the levels of entire males to those of surgically castrated pigs. After the second injection, pigs of both vaccination groups performed no mountings, in contrast with entire male pigs of the same age. Skin lesions at slaughter were fewer and less severe for vaccinated pigs compared with entire male pigs. No difference in income per carcass was observed for surgically castrated or vaccinated pigs. However, for entire male pigs the income was lower, as the payment system in Sweden also takes into consideration the additional cost for boar taint analyses and reduced payment for tainted carcasses. Under our experimental conditions, early vaccination with Improvac can be used as an alternative to the recommended schedule to minimise problematic behaviour with unaffected profitability.
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| 10. |
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| 11. |
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| 12. |
- Bodén, Stina, et al.
(författare)
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Dietary patterns, untargeted metabolite profiles and their association with colorectal cancer risk
- 2024
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Ingår i: Scientific Reports. - : Springer Nature. - 2045-2322 .- 2045-2322. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- We investigated data-driven and hypothesis-driven dietary patterns and their association to plasma metabolite profiles and subsequent colorectal cancer (CRC) risk in 680 CRC cases and individually matched controls. Dietary patterns were identified from combined exploratory/confirmatory factor analysis. We assessed association to LC–MS metabolic profiles by random forest regression and to CRC risk by multivariable conditional logistic regression. Principal component analysis was used on metabolite features selected to reflect dietary exposures. Component scores were associated to CRC risk and dietary exposures using partial Spearman correlation. We identified 12 data-driven dietary patterns, of which a breakfast food pattern showed an inverse association with CRC risk (OR per standard deviation increase 0.89, 95% CI 0.80–1.00, p = 0.04). This pattern was also inversely associated with risk of distal colon cancer (0.75, 0.61–0.96, p = 0.01) and was more pronounced in women (0.69, 0.49–0.96, p = 0.03). Associations between meat, fast-food, fruit soup/rice patterns and CRC risk were modified by tumor location in women. Alcohol as well as fruit and vegetables associated with metabolite profiles (Q2 0.22 and 0.26, respectively). One metabolite reflecting alcohol intake associated with increased CRC risk, whereas three metabolites reflecting fiber, wholegrain, and fruit and vegetables associated with decreased CRC risk.
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| 13. |
- Brunius, Carl, et al.
(författare)
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A modified high performance liquid chromatographic method for simultaneous quantification of skatole and indole in porcine plasma
- 2012
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Ingår i: Acta Veterinaria Brno. - : University of Veterinary and Pharmaceutical Sciences. - 0001-7213 .- 1801-7576. ; 81, s. 153-158
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Tidskriftsartikel (refereegranskat)abstract
- A simplified high-performance liquid chromatography method to measure skatole and indole in porcine plasma without the use of acetonitrile was developed and validated in this study. The mobile phase consisted of water and methanol used in a gradient programme. Fluorescence detection was performed on the supernatant obtained from plasma after protein precipitation with 100% acetone. Limits of quantification were 0.5 ng.ml(-1) for skatole and 1.0 ng.ml(-1) for indole. Accuracy and precision had less than 12% deviation in the linear ranges (0.5-256 ng.ml(-1) and R-2 = 0.9999 for skatole, 1.0-256 ng.ml(-1) and R-2 = 0.9999 for indole). The correlation between plasma and serum concentrations was strong for skatole (slope = 1.01, R-2 = 0.999) and moderate for indole (slope = 0.65, R-2 = 0.95). Analysis of skatole in plasma was in good accordance with our previous acetonitrile-based method (slope = 0.91, R-2 = 0.988). The proposed method is suited for rapid routine analysis because of its high selectivity, accuracy and precision. Furthermore, it needs only simple sample preparation and the use of methanol instead of acetonitrile in the mobile phase. This method is of practical use to researchers in the field of boar taint.
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| 14. |
- Brunius, Carl
(författare)
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Early immunocastration of male pigs : effects on physiology, performance and behaviour
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The aim of this study was to investigate the effects of prepubertal or early pubertal vaccination against GnRH using Improvac® (Pfizer Ltd.) on boar taint, reproductive organs, anabolic hormones, cytochrome P450 enzymes, performance and behaviour. Crossbred male pigs (n=192) were randomly allocated to four groups: one group surgically castrated without anaesthesia, a second group receiving early vaccination (at ages 10 and 14 weeks), a third standard vaccinated group (at ages 16 and 20 weeks), and a fourth group of entire male pigs. After the second injection, antibody titres increased rapidly and testicular steroids decreased to the low levels of castrates. Reproductive organs were small in vaccinated pigs and smaller after early vaccination. Spermatogenesis and steroidogenesis were disrupted with a more severe, possibly irreversible effect after early vaccination. Oestradiol was suppressed for castrated and vaccinated pigs. IGF-1 was lowest for castrates and highest for entire male pigs, with vaccinated pigs at an intermediate level. Hepatic CYP450 mRNA expression was highest for castrated and early vaccinated pigs, and lowest for entire male pigs, suggesting suppression at the transcriptional level of CYP1A2, CYP2A and CYP2E1 by testicular steroids. This did not correspond exactly with protein expression and activities, suggesting other regulations for some CYP450s. The levels of skatole and androstenone in adipose tissue were low in castrated and vaccinated pigs, whereas entire male pigs had elevated levels. Daily weight gain and feed conversion did not differ between groups and income per carcass did not differ between castrated or vaccinated pigs. The income was lower for entire male pigs, due to the additional cost for boar taint analyses and reduced payment for tainted carcasses. After vaccination, the frequency of interactions, both problematic and non-problematic, decreased from the levels of entire males to those of surgically castrated pigs. Under these conditions, early vaccination with Improvac can be used to control boar taint, testicular function and behaviour with unaffected profitability. Thus, the flexi¬bility of vaccination may be extended, implying advantages in terms of animal welfare and sustainability.
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| 15. |
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| 16. |
- Brunius, Carl, et al.
(författare)
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Expression and activities of hepatic cytochrome P450 (CYP1A, CYP2A and CYP2E1) in entire and castrated male pigs
- 2012
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Ingår i: Animal. - 1751-7311 .- 1751-732X. ; 6, s. 271-277
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Tidskriftsartikel (refereegranskat)abstract
- This study aimed to provide further insights into the mechanism of in vivo regulation of cytochrome P450 (CYP450) 1A, 2A and 2E1 activities in pigs with different levels of testicular steroids. Hepatic mRNA and protein expression and enzymatic activity of CYP1A, CYP2A and CYP2E1 were compared between entire male and castrated pigs. Castration was performed either surgically or immunologically. The pigs were divided into four groups. In the first group, piglets were surgically castrated without anaesthesia. Immunological castration was performed by vaccination with Improvac (R) (Pfizer Ltd). Vaccinated pigs were subdivided into two groups according to the vaccination regimen: early and standard vaccination. Pigs in the early vaccination group were vaccinated when aged 11 and 15 weeks. Pigs in the standard vaccination group were vaccinated when aged 17 and 21 weeks. In the control group, pigs remained intact throughout the study. Hepatic CYP450 mRNA expression, measured by real-time RT-PCR, differed significantly between groups for all isoforms measured: CYP1A2 (P = 0.002), 2A (P = 0.000) and 2E1 (P = 0.002). Lower CYP450 mRNA in entire male pigs suggests suppression of CYP1A2, CYP2A and CYP2E1 by testicular steroids at the transcriptional level. However, this suppression was not always reflected in decreased protein expression and activities of these isoforms, suggesting that at least some CYP450s (e. g. CYP2E1) are regulated by a post-transcriptional mechanism.
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| 17. |
- Brunius, Carl, et al.
(författare)
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Expression of hepatic 3 beta-hydroxysteroid dehydrogenase and sulfotransferase 2A1 in entire and castrated male pigs
- 2012
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Ingår i: Molecular Biology Reports. - : Springer Science and Business Media LLC. - 0301-4851 .- 1573-4978. ; 39, s. 7927-7932
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Tidskriftsartikel (refereegranskat)abstract
- The present study investigated the effect of surgical (SC) and immunological castration on the steroid metabolizing enzymes 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) and sulfotransferase 2A1 (SULT2A1) in male pigs. Thirty-two male pigs were divided in four groups; in one group the pigs were SC before the age of 7 days, two groups were injected with Improvac(A (R)) a vaccine against gonadotropin releasing hormone (immunological castration), while the pigs in the last group remained entire males (EMs). Immunological castration was in one group performed by vaccine injection at ages 11 and 14 weeks, while the other group received injections at ages 17 and 21 weeks. Plasma, adipose and liver tissue were collected at the time of slaughter. Plasma was analyzed for concentrations of testosterone and oestradiol. The adipose tissue was analyzed for the concentration of androstenone, while the liver tissue was analyzed for mRNA and protein expression of 3 beta-HSD and SULT2A1. Independent of method, all castrated pigs showed greater mRNA and protein expression of 3 beta-HSD and lower levels of all steroids in plasma compared with EMs. Moreover, there was a strong correlation between mRNA and protein expression of 3 beta-HSD and steroid levels. The same was not valid for expression of SULT2A1. It is concluded that steroid levels can increase expression of the steroid metabolizing enzyme 3 beta-HSD and thereby influence steroid metabolism, e.g. of androstenone.
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| 18. |
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| 19. |
- Brunius, Carl, et al.
(författare)
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Feeding dried chicory root to pigs decrease androstenone accumulation in fat by increasing hepatic 3 beta hydroxysteroid dehydrogenase expression
- 2012
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Ingår i: Journal of Steroid Biochemistry and Molecular Biology. - : Elsevier BV. - 0960-0760 .- 1879-1220. ; 130, s. 90-95
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Tidskriftsartikel (refereegranskat)abstract
- The present study investigated the in vivo effect of chicory root on testicular steroid concentrations and androstenone metabolizing enzymes in entire male pigs. Furthermore, the effect on skatole and indole concentrations in plasma and adipose tissue was investigated. The pigs were divided into two groups; one receiving experimental feed containing 10% dried chicory root for 16 days before slaughter, the control group was fed a standard diet. Plasma, adipose and liver tissue samples were collected at slaughter. Plasma was analyzed for the concentration of testosterone, estradiol, insulin-like growth factor 1 (IGF-1), skatole and indole. Adipose tissue was analyzed for the concentration of androstenone, skatole and indole, while the liver tissue was analyzed for mRNA and protein expressions of 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD), sulfotransferase 2A1 and heat-shock protein 70 (HSP70). The results showed that the androstenone concentrations in the adipose tissue of chicory fed pigs were significantly (p < 0.05) lower and indole concentrations were higher (p < 0.05) compared to control fed pigs. Moreover the chicory root fed pigs had increased mRNA and protein expression of 3 beta-HSD and decreased HSP70 expression (p < 0.05). Testosterone and IGF-1 concentrations in plasma as well as skatole concentrations in adipose tissue were not altered by dietary intake of chicory root. It is concluded that chicory root in the diet reduces the concentration of androstenone in adipose tissue via induction of 3 beta-HSD, and that these changes were not due to increased cellular stress. (C) 2012 Elsevier Ltd. All rights reserved.
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| 20. |
- Brunius, Carl, et al.
(författare)
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Large-scale untargeted LC-MS metabolomics data correction using between-batch feature alignment and cluster-based within-batch signal intensity drift correction
- 2016
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Ingår i: Metabolomics. - : Springer Science and Business Media LLC. - 1573-3882 .- 1573-3890. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- Introduction Liquid chromatography-mass spectrometry (LC-MS) is a commonly used technique in untargeted metabolomics owing to broad coverage of metabolites, high sensitivity and simple sample preparation. However, data generated from multiple batches are affected by measurement errors inherent to alterations in signal intensity, drift in mass accuracy and retention times between samples both within and between batches. These measurement errors reduce repeatability and reproducibility and may thus decrease the power to detect biological responses and obscure interpretation.Objective Our aim was to develop procedures to address and correct for within-and between-batch variability in processing multiple-batch untargeted LC-MS metabolomics data to increase their quality.Methods Algorithms were developed for: (i) alignment and merging of features that are systematically misaligned between batches, through aggregating feature presence/missingness on batch level and combining similar features worthogonally present between batches; and (ii) within-batch drift correction using a cluster-based approach that allows multiple drift patterns within batch. Furthermore, a heuristic criterion was developed for the feature-wise choice of reference-based or population-based between-batch normalisation.Results In authentic data, between-batch alignment resulted in picking 15 % more features and deconvoluting 15 % of features previously erroneously aligned. Within-batch correction provided a decrease in median quality control feature coefficient of variation from 20.5 to 15.1 %. Algorithms are open source and available as an R package ('batchCorr').Conclusions The developed procedures provide unbiased measures of improved data quality, with implications for improved data analysis. Although developed for LC-MS based metabolomics, these methods are generic and can be applied to other data suffering from similar limitations.
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| 21. |
- Brunius, Carl, et al.
(författare)
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Metabolomics for Improved Understanding and Prediction of Cardiometabolic Diseases—Recent Findings from Human Studies
- 2015
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Ingår i: Current Nutrition Reports. - : Springer Science and Business Media LLC. - 2161-3311. ; 4, s. 348-364
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Tidskriftsartikel (refereegranskat)abstract
- Cardiometabolic dieases are the main causes of morbidity and mortality worldwide. Despite large clinical and basic research efforts to improve the understanding of the molecular mechanisms of these conditions and to develop prediagnostic markers still remains a challenge. Recently, targeted and untargeted metabolomics technique became available for comprehensive studies of small molecules in biological samples in large-scale studies. MS- or NMR-based techniques dominate and have recently been used extensively in studies to identify predictive biomarkers, monitoring therapeutic response as well as in basic mechanism studies of obesity, metabolic syndrome, type 2 diabetes, and heart disease. Here, we review the recent findings from such studies. Findings highlight the roleof branched-chain amino acids, acyl carnitines and other lipid classes in these conditions. Putative biomarkers for disease conditions have been identified but mechanistic understanding of their role in the disease development and progression typically remains to be elucidated. Future studies should to a greater extent be designed to allow studies on causal mechanistic links between metabolites and disease.
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| 22. |
- Brunius, Carl, 1974, et al.
(författare)
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Prediction and modeling of pre-analytical sampling errors as a strategy to improve plasma NMR metabolomics data
- 2017
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Ingår i: Bioinformatics. - : Oxford University Press (OUP). - 1367-4803 .- 1460-2059 .- 1367-4811. ; 33:22, s. 3567-3574
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Tidskriftsartikel (refereegranskat)abstract
- Biobanks are important infrastructures for life science research. Optimal sample handling regarding e.g. collection and processing of biological samples is highly complex, with many variables that could alter sample integrity and even more complex when considering multiple study centers or using legacy samples with limited documentation on sample management. Novel means to understand and take into account such variability would enable high-quality research on archived samples. This study investigated whether pre-analytical sample variability could be predicted and reduced by modeling alterations in the plasma metabolome, measured by NMR, as a function of pre-centrifugation conditions (1-36 h pre-centrifugation delay time at 4 A degrees C and 22 A degrees C) in 16 individuals. Pre-centrifugation temperature and delay times were predicted using random forest modeling and performance was validated on independent samples. Alterations in the metabolome were modeled at each temperature using a cluster-based approach, revealing reproducible effects of delay time on energy metabolism intermediates at both temperatures, but more pronounced at 22 A degrees C. Moreover, pre-centrifugation delay at 4 A degrees C resulted in large, specific variability at 3 h, predominantly of lipids. Pre-analytical sample handling error correction resulted in significant improvement of data quality, particularly at 22 A degrees C. This approach offers the possibility to predict pre-centrifugation delay temperature and time in biobanked samples before use in costly downstream applications. Moreover, the results suggest potential to decrease the impact of undesired, delay-induced variability. However, these findings need to be validated in multiple, large sample sets and with analytical techniques covering a wider range of the metabolome, such as LC-MS.
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| 23. |
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| 24. |
- Brunius, Carl, et al.
(författare)
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Skatole metabolites in urine as a biological marker of pigs with enhanced hepatic metabolism
- 2016
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Ingår i: Animal. - 1751-7311 .- 1751-732X. ; 10, s. 1734-1740
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Tidskriftsartikel (refereegranskat)abstract
- Boar taint is a quality defect in meat, related to accumulation of skatole and androstenone in male pigs. The levels of skatole and its main metabolites in plasma and urine samples were measured with a validated liquid chromatography-MS method and related to activity of hepatic cytochrome P450 (CYP450) in order to identify fast metabolizing' pigs. Urine (n=46), blood (n=12), liver (n=25) and adipose tissue (n=46) were sampled from a total of 46 entire male pigs. Skatole levels in fat were negatively correlated to CYP2E1 activity and positively to 3-hydroxy-3-methyloxindole (HMOI), indole-3-carboxylic acid (ICA) and 2-aminoacetophenone in urine. HMOI and ICA levels in urine were the best predictors of high skatole levels in fat. In summary, the present study provided further evidence for the key role of CYP2E1 in skatole metabolism and suggested that measurement of HMOI and/or ICA in urine might provide information about skatole levels in live pigs.
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| 25. |
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