| 1. |
- Preinbergs, Julia, 1989-
(författare)
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Testosterone Analysis in Hair
- 2022
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The effects of testosterone in the body are dependent on the concentrations at the target organs, as well as the susceptibility of the androgen receptor. Steroid hormones circulate in the bloodstream bound to proteins, and only a small part is unbound and free to exert its effect at the receptors. Due to the diurnal variation in testosterone levels, the measured concentrations can change rapidly. Thus, a kind of "long-term measure" of the average free testosterone concentration would facilitate the understanding of the hormones' long-term effects on target organs.Hair seems at first sight to be a suitable matrix. The current theory is that only the free, unbound fraction of hormones passively diffuse from the bloodstream into the hair matrix as the hair grows. In this thesis, we have developed an analysis capable of analysing testosterone in the hair of men and women. We have systematically explored potential confounding factors and the pattern of testosterone concentrations in different hair segments. Furthermore, we have sought to confirm biological differences such as sex, age and BMI which affect hormone concentrations in the blood. Finally, we have investigated how hair testosterone concentrations change in relation to treatment with oral contraceptives and before an acute myocardial infarction.Our conclusions are that it is possible to measure testosterone in extracts from hair in very low concentrations. The choice of measurement method needs to balance between high specificity, which mass spectrometry can offer, and adequate detection limits, which can be achieved with immunoassays. Hair testosterone concentrations correlate significantly with testosterone concentrations in saliva, which suggests that hair testosterone reflects the average hormone concentrations in the body. The significant variation in hair growth rate within and between individuals impedes the theoretical relationship between certain hair segments and a specific time in the past. Hair testosterone concentrations are affected by the frequency of hair washing, cosmetic hair treatment, natural hair colour and the biological sex. In hair samples taken shortly after a patient was admitted to hospital due to a myocardial infarction, lower concentrations of testosterone can be seen in hair compared to individuals of the same age who have not had an acute heart attack. This suggests that a reduction in testosterone concentrations occurs shortly before the heart attack, independently of other cardiovascular risk factors. Reduced testosterone concentrations could thus be an independent risk factor for developing an acute myocardial infarction.
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| 2. |
- Babarro, Izaro, et al.
(författare)
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Hair cortisol as a biomarker of chronic stress in preadolescents: influence of school context and bullying
- 2023
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Ingår i: Child Neuropsychology. - : Informa UK Limited. - 0929-7049 .- 1744-4136. ; 29:5, s. 742-759
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Tidskriftsartikel (refereegranskat)abstract
- Bullying has been identified as the most common form of aggression and a major source of stress among children and adolescents. The main objective of this study was to analyze the association that school context in general and bullying in particular might have with hair cortisol concentration (HCC), examining the effect of executive function and sex on this association. The study included 659 11-year-old preadolescents from the cohorts of Gipuzkoa and Sabadell of the INMA (INfancia y Medio Ambiente-Children and Environment) project. We gathered information about school-related factors (bullying, school environment, problems with peers and academic performance) and executive function (risky decision-making). Hair samples were collected to measure cortisol concentrations and Structural Equation Modeling was used to examine associations between school-related factors, executive function and HCC. Results showed that being involved as a bully/victim was related to higher HCC and, higher HCC was associated with poorer executive function. This study may contribute to a better understanding of the consequences that chronic exposure to a stressful factors may have on preadolescents' health and developmental outcomes. Besides, our results are relevant for designing programs for prevention and intervention, which could modify individual physiological responses to stress and reduce the effects of stress on the health.
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| 3. |
- Carlstedt, Anders, et al.
(författare)
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Management of Diastasis of the Rectus Abdominis Muscles : Recommendations for Swedish National Guidelines
- 2021
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Ingår i: Scandinavian Journal of Surgery. - : Sage Publications. - 1457-4969 .- 1799-7267. ; 10:3, s. 452-459
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Tidskriftsartikel (refereegranskat)abstract
- Background: Diastasis of the rectus abdominis muscle is a common condition. There are no generally accepted criteria for diagnosis or treatment of diastasis of the rectus abdominis muscle, which causes uncertainty for the patient and healthcare providers alike. Methods: The consensus document was created by a group of Swedish surgeons and based on a structured literature review and practical experience. Results: The proposed criteria for diagnosis and treatment of diastasis of the rectus abdominis muscle are as follows: (1) Diastasis diagnosed at clinical examination using a caliper or ruler for measurement. Diagnostic imaging by ultrasound or other imaging modality, should be performed when concurrent umbilical or epigastric hernia or other cause of the patient's symptoms cannot be excluded. (2) Physiotherapy is the firsthand treatment for diastasis of the rectus abdominis muscle. Surgery should only be considered in diastasis of the rectus abdominis muscle patients with functional impairment, and not until the patient has undergone a standardized 6-month abdominal core training program. (3) The largest width of the diastasis should be at least 5 cm before surgical treatment is considered. In case of pronounced abdominal bulging or concomitant ventral hernia, surgery may be considered in patients with a smaller diastasis. (4) When surgery is undertaken, at least 2 years should have elapsed since last childbirth and future pregnancy should not be planned. (5) Plication of the linea alba is the firsthand surgical technique. Other techniques may be used but have not been found superior. Discussion: The level of evidence behind these statements varies, but they are intended to lay down a standard strategy for treatment of diastasis of the rectus abdominis muscle and to enable uniformity of management.
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| 4. |
- Gustavsson, Erik, 1982-, et al.
(författare)
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The ethical dilemma ofgranulocyte transfusions
- 2020
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Ingår i: Clinical Ethics. - : Sage Publications. - 1477-7509 .- 1758-101X. ; 15:3, s. 156-161
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Tidskriftsartikel (refereegranskat)abstract
- Granulocyte transfusions have been administered to patients with life-threatening infections for more than five decades. However, to what extent this should be the case is far from established. On the one hand, the clinical effects of these transfusions are difficult to prove in clinical studies, and the donors of granulocytes may be exposed to certain risks. On the other hand, clinical experience seems to support the idea that granulocyte transfusions do play an important role for severely ill patients, and the donors are primarily motivated by altruistic reasons. In this paper, we first discuss the ethical issues that arise from the fact that there is a conflict between clinical experience and the results from the attempts to perform randomized control trials, and second, the risk/benefit assessment that has to be made between two different parties, namely the recipient and the donor of granulocyte transfusions.
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| 5. |
- Hedin, Christina, et al.
(författare)
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Intraoperativ strålbehandling vid primar operation for bröstcancer : TARGIT-A-studien ej konklusiv
- 2018
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Ingår i: Läkartidningen. - Stockholm, Sweden : Läkartidningen Förlag AB. - 0023-7205 .- 1652-7518. ; 115
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Forskningsöversikt (refereegranskat)abstract
- The TARGIT-A (TARGeted Intraoperative radioTherapy) multicentre study of early breast cancer compared intraoperative radiotherapy with external radiotherapy. While the intraoperative radiotherapy was standardised, the external postoperative comparison treatment followed established routines in the participating treatment centres resulting in substantial variations in dosages and treatment durations. The uncertainties in the interpretation of the study results created by the design of the TARGIT-A study constitute substantial obstacles to the possible introduction of intraoperative radiotherapy for early breast cancer.
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| 6. |
- Kallner, Anders, et al.
(författare)
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An experimental study of methods for the analysis of variance components in the inference of laboratory information
- 2020
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Ingår i: Scandinavian Journal of Clinical and Laboratory Investigation. - : TAYLOR & FRANCIS LTD. - 0036-5513 .- 1502-7686. ; 80:1, s. 73-80
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Tidskriftsartikel (refereegranskat)abstract
- Measurement uncertainty (MU) can be estimated and calculated by different procedures, representing different aspects and intended use. It is appropriate to distinguish between uncertainty determined under repeatability and reproducibility conditions, and to distinguish causes of variation using analysis of variance components. The intra-laboratory MU is frequently determined by repeated measurements of control material(s) of one or several concentrations during a prolonged period of time. We demonstrate, based on experimental results, how such results can be used to identify the repeatability, pure reproducibility and intra-laboratory variance as the sum of the two. Native patient material was used to establish repeatability using the Dahlberg formula for random differences between measurements and an expanded Dahlberg formula if a non-random difference, e.g. bias, was expected. Repeatability and reproducibility have different clinical relevance in intensive care compared to monitoring treatment of chronic diseases, comparison with reference intervals or screening.
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| 7. |
- Leijon, Ingemar, 1942-, et al.
(författare)
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God prognos för unga vuxna med mycket låg födelsevikt [Follow-up study of very low birthweight children in Sweden at the age of 27-28]
- 2020
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Ingår i: Läkartidningen. - Stockholm, Sweden : Sveriges Läkarförbund. - 0023-7205 .- 1652-7518. ; 117
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Tidskriftsartikel (refereegranskat)abstract
- Studies show that very low birthweight can be an important risk factor for mental problems, disturbed fertility and neuroendocrine dysregulation. In a regional long-term study 56 of 86 adult individuals 27 to 28 years of age with a very low birthweight were compared with normal birthweight controls. Analyses of self-reported mental health, socio-demographic factors, sex hormone levels, and hair cortisol levels showed no significant differences between the groups. However, in order to analyse subgroups with different risk factors from the newborn period or children with a variety of social background factors, larger patient groups are needed.
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| 8. |
- Leijon, Ingemar, 1942-, et al.
(författare)
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Self-reported mental health and cortisol activity at 27-28 years of age in individuals born with very low birthweight
- 2020
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Ingår i: Acta Paediatrica. - : Wiley-Blackwell Publishing Inc.. - 0803-5253 .- 1651-2227. ; 109:5, s. 948-958
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Tidskriftsartikel (refereegranskat)abstract
- AimTo assess mental health outcomes of very low birthweight (VLBW, <1500 g) subjects to adulthood and to examine salivary cortisol and hair cortisol levels and their relation to birth characteristics and mental health.MethodsA Swedish regional cohort of 56 VLBW subjects and 55 full‐term controls were assessed at the ages 27‐28 with adult self‐reported scales and the mean of 2 days diurnal salivary cortisol and hair cortisol. The cohorts had been assessed at 15 years of age with youth self‐reported scales.ResultsThere were no differences between the groups in youth self‐reported scales and adult self‐reported scores. The 24 participating VLBW girls scored lower on youth self‐reported scales externalising and total problem scores than the control girls. In adulthood, the 21 participating VLBW women had significantly higher morning concentrations of salivary cortisol than control women, P = .014. No significant associations were found between cortisol concentrations and adult self‐reported scales internalising, externalising and total scores.ConclusionSelf‐reported mental health in VLBW subjects was comparable with normal birthweight controls indicating a satisfying transition from adolescence to adulthood. VLBW females had higher morning salivary cortisol concentrations, suggesting a gender difference. We found no correlations between cortisol and mental health.
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| 9. |
- Loh, Tze Ping, et al.
(författare)
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The LEAP checklist for laboratory evaluation and analytical performance characteristics reporting of clinical measurement procedures
- 2024
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Ingår i: Annals of Clinical Biochemistry. - : Sage Publications. - 0004-5632 .- 1758-1001. ; 61:1, s. 3-7
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Tidskriftsartikel (refereegranskat)abstract
- Reporting a measurement procedure and its analytical performance following method evaluation in a peer-reviewed journal is an important means for clinical laboratory practitioners to share their findings. It also represents an important source of evidence base to help others make informed decisions about their practice. At present, there are significant variations in the information reported in laboratory medicine journal publications describing the analytical performance of measurement procedures. These variations also challenge authors, readers, reviewers and editors in deciding the quality of a submitted manuscript. The International Federation of Clinical Chemistry and Laboratory Medicine Working Group on Method Evaluation Protocols (IFCC WG-MEP) developed a checklist and recommends its adoption to enable a consistent approach to reporting method evaluation and analytical performance characteristics of measurement procedures in laboratory medicine journals. It is envisioned that the LEAP checklist will improve the standardisation of journal publications describing method evaluation and analytical performance characteristics, improving the quality of the evidence base that is relied upon by practitioners.
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| 10. |
- Lööv, Anna, 1990-, et al.
(författare)
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Diagnostic accuracy for colorectal cancer of a quantitative faecal immunochemical test in symptomatic primary care patients : a study protocol
- 2022
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Ingår i: Diagnostic and prognostic research. - : BioMed Central (BMC). - 2397-7523. ; 6:1
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: There is increasing evidence supporting the use of faecal immunochemical tests (FIT) in patients reporting symptoms associated with colorectal cancer (CRC), but most studies until now have focused on selected subjects already referred for investigation. We therefore set out to determine the accuracy and predictive values of FIT in a primary care population.METHOD: A prospective, multicentre, single-gated comparative diagnostic study on quantitative FIT in patients aged 40 years and above presenting in primary care with symptoms associated with CRC will be conducted. Patients representing the whole spectrum of severity of such symptoms met with in primary care will be eligible and identified by GPs. Participants will answer a short form on symptoms during the last month. They will provide two faecal samples from two separate days. Analyses will be performed within 5 days (QuikRead go®, Aidian Oy). The analytical working range is 10-200 μg Hb/g faeces. Reference test will be linked to the Swedish Colorectal Cancer Registry up to 2 years after inclusion. Accuracy, area under ROC curves, and predictive values will be calculated for one FIT compared to the highest value of two FIT and at cutoff < 10, 10-14.9, 15-19.9 and ≥ 20 μg Hb/g faeces. Subgroup analyses will be conducted for patients with anaemia and those reporting rectal bleeding. A model-based cost-effectiveness analysis based on the clinical accuracy study will be performed. Based on previous literature, we hypothesized that the sensitivity of the highest value of two FIT at cutoff 10 μg Hb/g faeces will be 95% (95% CI + / - 15%). The prevalence of CRC in the study population was estimated to be 2%, and the rate of non-responders to be 1/6. In all, 3000 patients will be invited at 30 primary care centres.DISCUSSION: This study will generate important clinical real-life structured data on accuracy and predictive values of FIT in the most critical population for work-up of CRC, i.e. patients presenting with at times ambiguous symptoms in primary care. It will help establish the role of FIT in this large group.
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