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- Sinkvist, David, et al.
(författare)
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Five Year Data and Results of Continuous Quality Improvement Using SKURT
- 2017
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Ingår i: Educational Research Applications. - IL, USA : Gavin Publishers. - 2575-7032. ; 2017:05
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Tidskriftsartikel (refereegranskat)abstract
- Student rating of teaching isessentialfor attaining and maintaining higheducational quality.A quality improvement system, SKURT,based on digital online weekly combined quantitative, ten-graded scale, and qualitative, open-ended free text, group feedback from medical students was developed. Students rated all educational, non-clerkship, items throughout the entire medical program, spanning eleven terms. The results were semi-publicly available for students and faculty at a Swedish university. This study describes datafrom five-year use of the system,focusing on how the use of SKURT influenced educational items found to be in the most substantial need for improvements.Statistically but hardly practically significant improvement in average feedback grade was found during the observation period (average 7.07 in 2009 to 7.24 in 2013 (p<0.001)).The medical program was already in 2007recognized ascenter of excellent quality in higher education. When analyzing the 18 lectures with lowest outcome in the spring 2009 compared to the fall 2013, five were discontinued. The remaining 13 lectures improved significantly (p<0.001) 116% from 2.94 (SD 0.92) to 6.34 (SD 2.58). A weekly group feedback system employing the principles used in SKURTis useful forimproving the quality of medical education particularlyby improvingthe items with the lowest ratings.
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2. |
- Sinkvist, David, 1986-, et al.
(författare)
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SKURT: Quality Improvement System with Comprehensive Weekly Digital Student Group Feedback
- 2017
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Ingår i: Educational Research Applications. - : Gavin Publishers. - 2575-7032. ; 2017:5
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Tidskriftsartikel (refereegranskat)abstract
- Students’ role in evaluation and rating of teachers and education has been extensively researched for nearly a century. Applied worldwide, students’ ratings account for the majority of the available data.We created a new quality improvement system, SKURT, using digital online weekly combined quantitative, ten-graded scale, and qualitative, open-ended free text, group feedback from medical students. Students rated all educational, non-clerkship, items throughout the entire medical program, spanning eleven terms. The rating process is since 2008 an integral part of a medical program at a Swedish university. The results are, after a screening process, semi-publicly available on-demand, for students and faculty, creating a feedback loop enabling continuous improvement of quality.A thorough literature search of students rating of teaching found no other corresponding weekly group rating system spanning all educational items. Quality improvement systems based on similar principles as SKURT can uncover problem areas that are difficult to find using other rating systems and has the potential to circumvent several biases, risks and shortcomings of traditional rating systems in current use.
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3. |
- Theodorsson, Annette, 1958-, et al.
(författare)
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Hypothermia-induced increase in galanin concentrations and ischemic neuroprotection in the rat brain
- 2008
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Ingår i: Neuropeptides. - : Elsevier BV. - 0143-4179 .- 1532-2785. ; 42:1, s. 79-87
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Tidskriftsartikel (refereegranskat)abstract
- The effects of hypothermia on galanin concentrations and the relation between ischemic brain lesions, hypothermia and galanin concentrations in a transient and focal rat stroke model were investigated in order to elucidate whether hypothermia-induced alterations in galanin concentrations could constitute a part of the established neuroprotective effect of hypothermia. Female rats were allocated to normothermia (37 °C) or hypothermia (33 °C) treatments during a 60 min microclip middle cerebral artery occlusion. The ischemic lesions were visualized after observation periods of 2 or 7 days and the concentration of galanin measured by radioimmunoassay in extracts of punch biopsies from both the lesioned and the contralateral control hemisphere. Hypothermia-induced an overall increase in the concentrations of immunoreactive galanin (p < 0.001). The elevated galanin levels were predominantly found in the non-ischemic control hemisphere, in the hippocampus, thalamus and the posterior part of parietal cortex. The galanin concentrations were lower in the ischemic hemisphere in both the normo- and hypothermic animals compared to the corresponding contra lateral intact hemisphere (p = 0.049). The factor of time, 2 respectively 7 days, did not show any significant difference regarding the galanin concentrations (p = 0.844). Multivariate analyses of variance revealed significant effect of ischemia on the size of the ischemic brain lesions (p = 0.001) but no overall effect of temperature when data from both 2 and 7 days observation periods were analyzed together. The ischemic lesions were generally larger at 33 degrees after 2 days (p = 0.230). Prolonged observation time of 7 days resulted in a significant reduction of the ischemic brain lesion (p = 0.011) with smaller ischemic lesions in the hypothermic group. Our data support the notion that hypothermia-induced increase in the tissue concentrations of galanin in the brain are the result of changes from optimal homeostatic conditions - the hypothermia-induced stress - rather than the ischemia/re-perfusion lesion induced changes in galanin concentrations. Hypothermia-induced elevation in galanin concentration is therefore not likely to be amongst the major protective mechanisms of hypothermia. © 2007 Elsevier Ltd. All rights reserved.
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9. |
- 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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11. |
- Bjellerup, P, et al.
(författare)
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Limited neuropeptide Y precursor processing in unfavourable metastatic neuroblastoma tumours
- 2000
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Ingår i: British Journal of Cancer. - 0007-0920 .- 1532-1827. ; 83:2, s. 171-176
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Tidskriftsartikel (refereegranskat)abstract
- Neuropeptide Y (NPY) is found at high concentrations in neural crest-derived tumours and has been implicated as a regulatory peptide in tumour growth and differentiation. Neuroblastomas, ganglioneuromas and phaeochromocytomas with significant concentrations of NPY-like immunoreactivity were investigated for different molecular forms of NPY and for significance of proNPY processing. Gel-permeation chromatography identified intact NPY (1-36) in all tumours, whereas proNPY (69 amino acids) was detected only in control adrenal tissue and malignant neuroblastomas. Purification of NPY-like immunoreactivity in tumour extracts and structural characterization revealed that both NPY (1-36) and the truncated form NPY (3-36) was present. The degree of processing of proNPY to NPY in tumour tissue was lower in advanced neuroblastomas with regional or metastatic spread (stage 3 and 4) (n = 6), (41%, 12-100%, median, range), compared to the less aggressive stage 1, 2 and 4S tumours (n = 12), (93%, 69-100%), (P = 0.012). ProNPY processing of less than 50% was correlated with poor clinical outcome (P = 0.004). MYCN oncogene amplification was also correlated to a low degree of proNPY processing (P = 0.025). In summary, a low degree of proNPY processing was correlated to clinical advanced stage and poor outcome in neuroblastomas. ProNPY/NPY processing generated molecular forms of NPY with known differences in NPY-receptor selectivity, implicating a potential for in vivo modulation of NPY-like effects in tumour tissue. (C) 2000 Cancer Research Campaign.
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13. |
- Bracci-Laudiero, Luisa, et al.
(författare)
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NGF modulates CGRP synthesis in human B-lymphocytes : A possible anti-inflammatory action of NGF?
- 2002
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Ingår i: Journal of Neuroimmunology. - 0165-5728 .- 1872-8421. ; 123:1-2, s. 58-65
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Tidskriftsartikel (refereegranskat)abstract
- We investigated whether the sensory neuropeptide, calcitonin gene-related peptide (CGRP), could be synthesised by human lymphocytes. Our results indicate that in activated B-cells, there is a strong expression of CGRP gene transcripts, which is almost absent in resting cells. Since B-cells autocrinally produce NGF, the neutralisation of endogenous NGF by anti-NGF antibodies resulted in a marked reduction in CGRP expression in both resting and activated B-cells. Thus, NGF appears to directly affect the synthesis of CGRP in B-cells as in sensory neurons. By regulating CGRP synthesis in lymphocytes and neuronal cells, NGF can influence the intensity and duration of the immune response. ⌐ 2002 Elsevier Science B.V. All rights reserved.
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14. |
- 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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17. |
- Ehrström, M, et al.
(författare)
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Pharmacokinetic profile of orexin A and effects on plasma insulin and glucagon in the rat
- 2004
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Ingår i: Regulatory Peptides. - : Elsevier BV. - 0167-0115 .- 1873-1686. ; 119:3, s. 209-212
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Tidskriftsartikel (refereegranskat)abstract
- Orexin A (OXA) is found in the central nervous system (CNS) and in the gut. Peripheral administration of OXA to rats results in an inhibition of fasting motility. Plasma OXA increases during fasting and central administration of OXA increases food intake. The aim of the present study was to assess the pharmacokinetic profile of OXA and the effect of intravenously (IV) administered OXA on plasma concentrations of insulin and glucagon concentrations. Rats were given OXA IV (100 pmol kg-1 min-1) for time periods of 0, 10, 20, 30 min and for 10, 20, 30 min after ceasing a 30-min infusion. After each time period, rats were then sacrificed and blood obtained. OXA was also administered at increasing doses (0, 100, 300 and 500 pmol kg-1 min-1) for 30 min and blood was obtained. Plasma OXA, insulin and glucagon levels were measured using commercially available radioimmunoassay (RIA) kits. The plasma half-life of OXA was 27.1±9.5 min. Stepwise increasing infusion rates of OXA confirmed a linear concentration-time curve and thus first-order kinetics. Its volume of distribution indicated no binding to peripheral tissues. Plasma glucagon decreased during infusion of OXA, while insulin was unaffected. Plasma OXA was raised fourfold after food intake. Thus, OXA has a longer plasma half-life than many other peptides found in the gut. This needs to be taken into account when assessing effects of OXA on biological parameters after peripheral administration.reserved.
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19. |
- El-Nour, H, et al.
(författare)
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Study of innervation, sensory neuropeptides, and serotonin in murine contact allergic skin
- 2005
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Ingår i: Immunopharmacology and immunotoxicology. - 0892-3973 .- 1532-2513. ; 27:1, s. 67-76
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Tidskriftsartikel (refereegranskat)abstract
- Density of nerve fibers, axonal growth, calcitonin gene-related peptide (CGRP), and substance P, and serotonin immunoreactivity as well as concentration were all determined in a murine model of contact allergy. Female Balb/c mice were sensitized on the back with oxazolone and 6 days later challenged with the same antigen on the dorsal surface of the ears, while control mice received the vehicle only. Then, 24 hr postchallenge, one ear was processed for immunohistochemical staining, while the other was frozen and processed for gas chromatography-mass spectrometry or radioimmunoassay (RIA). Protein gene product 9.5 (PGP 9.5) positive nerve fibers showed a tendency to increase in inflamed ears versus control ears in epidermis as well as the dermis. Growth-associated protein-43 (GAP-43) positive fibers in the epidermis were increased (p < .01) in inflamed ears, compared with control ears, as was the case for the dermal fibers, indicating increased axonal growth. Total (epidermis and dermis) numbers of CGRP and substance P positive nerve fibers tended to increase in the inflamed skin in contrast to control skin. In contrast, RIA demonstrated a lower (p < .05) concentration of CGRP in the inflamed ears compared with controls and a tendency for substance P to decrease in concentration in eczematous ears versus controls. There was no difference in serotonin concentration, or in the number of serotonin positive mast cells, between the inflamed and control skin, whereas semiquantification of serotonin positive platelets showed an increase in the inflamed (++) compared with control ears (+). Our results indicate that 24 hr after being challenged with the antigen, at the peak of murine skin inflammation, axonal growth, sensory neuropeptides, as well as serotonin may be involved. Copyright © 2005 Taylor & Francis Inc.
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20. |
- El-Salhy, Magdy, 1951-, et al.
(författare)
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Effects of triple treatment with octreotide, galanin and serotonin on a human pancreas cancer cell line in xenografts
- 2005
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Ingår i: Histology and Histopathology. - 0213-3911 .- 1699-5848. ; 20:3, s. 745-752
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Tidskriftsartikel (refereegranskat)abstract
- Human pancreas cancer cells were implanted s.c. in nude mice. After 11 days, the mice were divided into two groups of 13. The first group received sterile saline solution and the second received triple therapy containing octreotide, galanin and serotonin, 40 μg/kg/day as a continuous i.p. infusion via an implanted osmotic pump for 14 days. Triple therapy prolonged the survival rate of the mice bearing human pancreatic carcinoma. Both the volume and weight of tumours in mice given triple therapy were less than in controls (not statistically significant). The proliferation index and the labelling index for epidermal growth factor (EGF) increased significantly in mice given triple therapy vis-á-vis controls. There was no statistically significant difference between control and treated tumours as regards, apoptotic index, necrosis, or number of tumour blood vessels. The increased survival rate was attributed to the reduced tumour load, since both weight and volume were reduced. It is most probable that octreotide was the responsible agent. Further investigation with single and double combinations of octreotide, galanin and serotonin are needed to identify the cause of increased cell proliferation in tumours subjected to these bioactive substances. Identifying the agent(s) inducing pancreatic cancer cell proliferation may be useful in combining a new treatment, as antagonists to these bioactive substances are available.
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21. |
- Grankvist, Kjell, et al.
(författare)
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Laboratoriernas verksamhet
- 2018. - 10
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Ingår i: Laurells Klinisk kemi i praktisk medicin. - Lund : Studentlitteratur AB. - 9789144119748 ; , s. 13-30
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Bokkapitel (refereegranskat)
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22. |
- Greaves, Ronda F, et al.
(författare)
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The IFCC Curriculum - phase 1.
- 2018
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Ingår i: EJIFCC. - 1650-3414. ; 29:1, s. 55-93
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Tidskriftsartikel (refereegranskat)
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23. |
- 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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24. |
- Hammarsten, Ola, et al.
(författare)
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Tolkning av analysresultat
- 2018. - 10
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Ingår i: Laurells Klinisk kemi i praktisk medicin. - Lund : Studentlitteratur AB. - 9789144119748 ; , s. 31-53
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Bokkapitel (refereegranskat)
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25. |
- 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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26. |
- Hellström, P. M., et al.
(författare)
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GLP-1 suppresses gastrointestinal motility and inhibits the migrating motor complex in healthy subjects and patients with irritable bowel syndrome
- 2008
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Ingår i: Neurogastroenterology and Motility. - : Wiley. - 1350-1925 .- 1365-2982. ; 20:6, s. 649-659
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Tidskriftsartikel (refereegranskat)abstract
- Glucagon-like peptide-1 (GLP-1) is released after food intake to act as an incretin. GLP-1 also inhibits gastric emptying and increases satiety. In rats, GLP-1 inhibits small bowel motility. Our aim was to study the effects of GLP-1 on gastrointestinal motility in healthy subjects and patients with irritable bowel syndrome (IBS). Antro-duodeno-jejunal manometry was carried out during a 4-h control period with saline, followed by a 4-h period with intravenous GLP-1 (healthy: 0.7 and 1.2 pmol kg-1 min-1 (n = 16), IBS, 1.2 and 2.5 pmol kg-1 min-1 (n = 14). Plasma was analysed for GLP-1 and gut hormones, and gut tissue expression of GLP-1 receptor was studied. In healthy subjects, GLP-1 0.7 pmol kg-1 min-1 reduced the migrating motor complexes (MMCs) from a median of 2 (range 2-3) to 0.5 (0-2), and motility index from 4.9 ± 0.1 to 4.3 ± 0.3 ln ∑(mmHg*s min-1) in jejunum, while GLP-1 1.2 pmol kg -1 min-1 diminshed MMCs from 2 (2-3) to 1.5 (1-2.5), and motility index from 5.2 ± 0.2 to 4.4 ± 0.2. In IBS patients, GLP-1 1.2 pmol kg-1 min-1 reduced the MMCs from 2.5 (2-3.5) to 1 (0-1.5) without affecting motility index. At 2.5 pmol kg-1 min -1 GLP-1 decreased MMCs from 2 (1.5-3) to 1 (0.5-1.5), and motility index from 5.2 ± 0.2 to 4.0 ± 0.5. Motility responses to GLP-1 were similar in antrum and duodenum. Presence of the GLP-1 receptor in the gut was verified by reverse transcriptase PCR. In conclusion, the gut peptide GLP-1 decreases motility in the antro-duodeno-jejunal region and inhibits the MMC in healthy subjects and IBS patients. © 2008 The Authors.
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27. |
- Holmberg, K, et al.
(författare)
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Generation and phenotypic characterization of a galanin overexpressing mouse
- 2005
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Ingår i: Neuroscience. - : Elsevier BV. - 0306-4522 .- 1873-7544. ; 133:1, s. 59-77
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Tidskriftsartikel (refereegranskat)abstract
- In most parts of the peripheral nervous system galanin is expressed at very low levels. To further understand the functional role of galanin, a mouse overexpressing galanin under the platelet-derived growth factor-B was generated, and high levels of galanin expression were observed in several peripheral tissues and spinal cord. Thus, a large proportion of neurons in autonomic and sensory ganglia were galanin-positive, as were most spinal motor neurons. Strong galanin-like immunoreactivity was also seen in nerve terminals in the corresponding target tissues, including skin, blood vessels, sweat and salivary glands, motor end-plates and the gray matter of the spinal cord. In transgenic superior cervical ganglia around half of all neuron profiles expressed galanin mRNA but axotomy did not cause a further increase, even if mRNA levels were increased in individual neurons. In transgenic dorsal root ganglia galanin mRNA was detected in around two thirds of all neuron profiles, including large ones, and after axotomy the percentage of galanin neuron profiles was similar in overexpressing and wild type mice. Axotomy reduced the total number of DRG neurons less in overexpressing than in wild type mice, indicating a modest rescue effect. Aging by itself increased galanin expression in the superior cervical ganglion in wild type and transgenic mice, and in the latter also in preganglionic cholinergic neurons projecting to the superior cervical ganglion. Galanin overexpressing mice showed an attenuated plasma extravasation, an increased pain response in the formalin test, and changes in muscle physiology, but did not differ from wild type mice in sudomotor function. These findings suggest that overexpressed galanin in some tissues of these mice can be released and via a receptor-mediated action influence pathophysiological processes. © 2005 Published by Elsevier Ltd on behalf of IBRO.
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28. |
- Jacobsson, Stefan, et al.
(författare)
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Anemier
- 2018. - 10
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Ingår i: Laurells klinisk kemi i praktisk medicin. - Lund : Studentlitteratur AB. - 9789144119748 ; , s. 209-264
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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29. |
- 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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31. |
- Kokaia, Merab, et al.
(författare)
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Suppressed kindling epileptogenesis in mice with ectopic overexpression of galanin
- 2001
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 98:24, s. 14006-14011
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Tidskriftsartikel (refereegranskat)abstract
- The neuropeptide galanin has been shown to suppress epileptic seizures. In cortical and hippocampal areas, galanin is normally mainly expressed in noradrenergic afferents. We have generated a mouse overexpressing galanin in neurons under the platelet-derived growth factor B promoter. RIA and HPLC analysis revealed up to 8-fold higher levels of galanin in transgenic as compared with wild-type mice. Ectopic galanin overexpression was detected especially in dentate granule cells and hippocampal and cortical pyramidal neurons. Galanin-overexpressing mice showed retardation of seizure generalization during hippocampal kindling, a model for human complex partial epilepsy. The high levels of galanin in mossy fibers found in the transgenic mice were further increased after seizures. Frequency facilitation of field excitatory postsynaptic potentials, a form of short-term synaptic plasticity assessed in hippocampal slices, was reduced in mossy fiber-CA3 cell synapses of galanin-overexpressing mice, indicating suppressed glutamate release. This effect was reversed by application of the putative galanin receptor antagonist M35. These data provide evidence that ectopically overexpressed galanin can be released and dampen the development of epilepsy by means of receptor-mediated action, at least partly by reducing glutamate release from mossy fibers.
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32. |
- Kristoffersen, Laila, et al.
(författare)
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Skin-to-skin contact during eye examination did not reduce pain compared to standard care with parental support in preterm infants
- 2019
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Ingår i: Acta Paediatrica. - : Wiley-Blackwell Publishing Inc.. - 0803-5253 .- 1651-2227. ; 108:8, s. 1434-1440
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Tidskriftsartikel (refereegranskat)abstract
- AIM: We compared the pain relieving effect of skin-to-skin contact versus standard care in the incubator during screening for retinopathy of prematurity.METHODS: This randomised crossover study included 35 preterm infants of less than 32 weeks of gestational age admitted to St Olavs University Hospital, Trondheim, Norway, between January 2014 and June 2016. Randomisation was for skin-to-skin with one of the parents or standard care with supportive positioning by parents for the first of two consecutive eye examinations. The pain score was measured twice using the Premature Infant Pain Profile (PIPP) during and after the eye examination. The infants' movement activity was video recorded after the examination.RESULTS: There was no difference in mean pain scores with skin-to-skin contact versus standard care during (10.2 vs. 10.3, p = 0.91) or after (7.0 vs. 6.8, p = 0.76) the procedure. Independent of the randomisation group, PIPP scores were lower than previous comparable studies have found. Bouts of movement activity were also the same whether the examination was conducted in skin-to-skin position or in the incubator (p = 0.91).CONCLUSION: Skin-to-skin contact during the eye examination did not provide additional pain relief compared to standard care where the parents were already a part of the multidimensional approach.
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33. |
- Kuteeva, Eugenia, et al.
(författare)
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Distribution of galanin and galanin transcript in the brain of a galanin-overexpressing transgenic mouse
- 2004
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Ingår i: Journal of Chemical Neuroanatomy. - : Elsevier BV. - 0891-0618 .- 1873-6300. ; 28:4, s. 185-216
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Tidskriftsartikel (refereegranskat)abstract
- The distribution of galanin mRNA-expressing cells and galanin-immunoreactive (IR) cell bodies and processes was studied in the brain of mice overexpressing galanin under the PDGF-B promoter (GalOE mice) and of wild type (WT) mice, both in colchicine-treated and non-treated animals. In this abstract, we only describe the results in GalOE mouse. A widespread ectopic expression of galanin (both mRNA and peptide) was found, that is a situation when neither transcript nor peptide could be seen in WT mice, not even after colchicine treatment. However, in some regions, such as claustrum, basolateral amygdala, thalamus, CA1 pyramidal cells, and Purkinje cells only galanin mRNA could be detected. In the forebrain galanin was seen in the mitral cells of the olfactory bulb, throughout the cortex, in the basolateral amygdaloid nucleus, claustrum, granular and pyramidal cell layers of the hippocampus, subiculum and presubiculum. In the thalamus, the anterodorsal, mediodorsal, intermediodorsal and mediodorsal lateral nuclei, the reuniens and reticular nuclei showed ectopic expression of galanin. Within the hypothalamus, neurons of the suprachiasmatic nucleus contained galanin. In the mesencephalon, the geniculate nucleus, nucleus ruber, the mesencephalic trigeminal and reticulotegmental nuclei ectopically expressed galanin. In the cerebellum, galanin was observed in the Purkinje cells and in the lateral and interposed cerebellar nuclei. In the pons, sensory and motor nuclei of the trigeminal nerve, the laterodorsal and dorsal tegmental nuclei, the pontine, reticulotegmental and gigantocellular reticular nuclei expressed galanin. Within the medulla oblongata, labeled cells were detected in the facial, ambiguus, prepositus, lateral paragigantocellular and lateral reticular nuclei, and spinal trigeminal nucleus. High densities of galanin-IR fibers were found in the axonal terminals of the lateral olfactory tract, the hippocampal and presumably the cerebellar mossy fibers system, in several thalamic and hypothalamic regions and the lower brain stem. Possible functional consequences of galanin overexpression are discussed.
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34. |
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35. |
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Laurells klinisk kemi i praktisk medicin
- 2018. - 10
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Samlingsverk (redaktörskap) (övrigt vetenskapligt/konstnärligt)abstract
- Denna tionde upplaga av Laurells Klinisk kemi i praktisk medicin utgör en grundlig bearbetning av det populära verket. Samtliga kapitel har reviderats och kapitlen om tolkning av analysresultat, vatten, elektrolyter, blodgaser, mag–tarmkanalen och immunologi har skrivits om från grunden; allt i samarbete mellan verksamma inom klinisk farmakologi, klinisk immunologi och klinisk kemi.?Kunskapsfragment inom medicin, inklusive klinisk kemi, är lättillgängliga på nätet men ger sällan den helhetsbild som behövs för en djupare förståelse och därmed optimal användning av laboratorieanalyser. Denna bok ger en sådan helhetsbild och kan användas såväl för att slå upp fakta om specifika analyser som för att förstå de sjukdomsmekanismer som är av betydelse för beställning och tolkning av laboratorieresultat.?Texten är organiserad utifrån kliniska problemområden och i balansgången mellan inslagen av laboratorium och medicin har tonvikten lagts på det medicinskt-diagnostiska snarare än på det laboratorietekniska. Fokus ligger på förståelsen av preanalytiska och analytiska faktorer vid tolkningen av laboratorieresultat samt av förståelsen av prevalens, sensitivitet, specificitet och liknande begrepp i det diagnostiska arbetet.?Föreliggande bok förväntas även fortsatt komma till god användning på avdelningar, mottagningar och vårdcentraler – överallt där man behöver ta laboratorieprover och tolka provsvar – men också bland studenter i medicin, biomedicin, biomedicinsk laboratorievetenskap och besläktade kunskapsområden.
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36. |
- 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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37. |
- 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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38. |
- 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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39. |
- Lund, Mari L., et al.
(författare)
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Enterochromaffin 5-HT cells : A major target for GLP-1 and gut microbial metabolites
- 2018
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Ingår i: MOLECULAR METABOLISM. - : Elsevier. - 2212-8778. ; 11, s. 70-83
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Tidskriftsartikel (refereegranskat)abstract
- Objectives5-HT storing enterochromaffin (EC) cells are believed to respond to nutrient and gut microbial components, and 5-HT receptor-expressing afferent vagal neurons have been described to be the major sensors of nutrients in the GI-tract. However, the molecular mechanism through which EC cells sense nutrients and gut microbiota is still unclear.Methods and resultsTPH1, the 5-HT generating enzyme, and chromogranin A, an acidic protein responsible for secretory granule storage of 5-HT, were highly enriched in FACS-purified EC cells from both small intestine and colon using a 5-HT antibody-based method. Surprisingly, EC cells from the small intestine did not express GPCRsensors for lipid and protein metabolites, such as FFAR1, GPR119, GPBAR1(TGR5), CaSR, and GPR142, in contrast to the neighboring GLP-1 storing enteroendocrine cell. However, the GLP-1 receptor was particularly highly expressed and enriched in EC cells as judged both by qPCR and by immunohistochemistryusing a receptor antibody. GLP-1 receptor agonists robustly stimulated 5-HT secretion from intestinal preparations using both HPLC and a specific amperometricmethod. Colonic EC cells expressed many different types of known and potential GPCR sensors of microbial metabolites including three receptors for SCFAs, i.e. FFAR2, OLF78, and OLF558 and receptors for aromatic acids, GPR35; secondary bile acids GPBAR1; and acyl-amides and lactate, GPR132.ConclusionNutrient metabolites apparently do not stimulate EC cells of the small intestine directly but through a paracrine mechanism involving GLP-1 secreted from neighboring enteroendocrine cells. In contrast, colonic EC cells are able to sense a multitude of different metabolites generated by the gut microbiota as well as gut hormones, including GLP-1.
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40. |
- Lundin, Cecilia, et al.
(författare)
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Sexual function and combined oral contraceptives : a randomised, placebo-controlled trial
- 2018
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Ingår i: Endocrine Connections. - : Bioscientifica. - 2049-3614. ; 7:11, s. 1208-1216
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The effect of combined oral contraceptives (COCs) on female sexuality has long been a matter of discussion, but placebo-controlled studies are lacking. Thus, the aim of the present study was to investigate if an oestradiol-containing COC influences sexual function.Design: Investigator-initiated, randomised, double-blinded, placebo-controlled clinical trial where 202 healthy women were randomised to a combined oral contraceptive (1.5 mg oestradiol and 2.5 mg nomegestrol acetate) or placebo for three treatment cycles.Methods: Sexual function at baseline and during the last week of the final treatment cycle was evaluated by the McCoy Female Sexuality Questionnaire. Serum and hair testosterone levels were assessed at the same time points.Results: Compared to placebo, COC use was associated with a small decrease in sexual interest (COC median change score: -2.0; interquartile range (IQR): -5.0 to 0.5 vs placebo: -1.0; IQR: -3.0 to 2.0, P=0.019), which remained following adjustment for change in self-rated depressive symptoms (B= -0.80 +/- 0.30, Wald =7.08, P=0.008). However, the proportion of women who reported a clinically relevant deterioration in sexual interest did not differ between COC or placebo users (COC 18 (22.2%) vs placebo 16 (17.8%), P=0.47). Change in other measured aspects of sexual function as well as total score of sexual function did not differ between the two treatments.Conclusions: This study suggests that use of oestradiol-based COCs is associated with reduced sexual interest. However, the changes are minute, and probably not of clinical relevance.
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41. |
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42. |
- Lördal, Mikael, et al.
(författare)
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A novel tachykinin NK2 receptor antagonist prevents motility-stimulating effects of neurokinin A in small intestine
- 2001
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Ingår i: British Journal of Pharmacology. - 0007-1188 .- 1476-5381. ; 134:1, s. 215-223
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Tidskriftsartikel (refereegranskat)abstract
- 1. MEN 11420 (nepadutant) is a potent, selective and competitive antagonist of tachykinin NK2 receptors. 2. The objective of the present study was to assess the capability of the drug to antagonize the stimulatory effects of neurokinin A (NKA) on gastrointestinal motility, as well as to change the fasting migrating motor complex (MMC). 3. Thirty-four male volunteers were randomized to treatment with either placebo or MEN 11420 in a double-blinded manner. Effects of MEN 11420 (8 mg intravenously) were evaluated as changes in phases I, II and III of MMC, as well as contraction frequency, amplitude and motility index during baseline conditions and during stimulation of motility using NKA (25 pmol kg-1 min-1 intravenously). 4. NKA preceded by placebo increased the fraction of time occupied by phase II, increased contraction frequency, amplitude and motility index. 5. MEN 11420 effectively antagonized the motility-stimulating effects of NKA. MEN 11420 reduced the phase II-stimulating effect of NKA. In addition, the stimulatory effect of NKA on contraction frequency and amplitude, as well as motility index were inhibited by MEN 11420. MEN 11420 did not affect the characteristics of MMC during saline infusion. 6. Plasma levels of MEN 11420 peaked during the first hour after infusion and decreased to less than half during the first 2 h. 7. In conclusion, intravenous MEN 11420 effectively inhibited NKA-stimulated, but not basal gastrointestinal motility, and was well tolerated by all subjects.
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43. |
- Löwbeer, Christian, et al.
(författare)
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Energiomsättning, diabetes och lipoproteinrubbningar
- 2018. - 10
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Ingår i: Laurells klinisk kemi i praktisk medicin. - Lund : Studentlitteratur AB. - 9789144119748 ; , s. 345-414
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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44. |
- 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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45. |
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46. |
- Martinez, Cristina A., et al.
(författare)
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Prenatal stress, anxiety and depression alter transcripts, proteins and pathways associated with immune responses at the maternal-fetal interface
- 2022
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Ingår i: Biology of Reproduction. - : Oxford University Press. - 0006-3363 .- 1529-7268. ; 106:3, s. 449-462
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Tidskriftsartikel (refereegranskat)abstract
- During pregnancy, the immune system is modified to allow developmental tolerance of the semi-allogeneic fetus and placenta to term. Pregnant women suffering from stress, anxiety, and depression show dysfunctions of their immune system that may be responsible for fetal and/or newborn disorders, provided that placental gene regulation is compromised. The present study explored the effects of maternal chronic self-perceived stress, anxiety, and depression during pregnancy on the expression of immune-related genes and pathways in term placenta. Pregnancies were clinically monitored with the Beck Anxiety Inventory (BAI) and Edinburgh Postnatal Depression Scale (EPDS). A cutoff threshold for BAI/EPDS of 10 divided patients into two groups: Index group (>10, n = 11) and a Control group (<10, n = 11), whose placentae were sampled at delivery. The placental samples were subjected to RNA-Sequencing, demonstrating that stress, anxiety, and depression during pregnancy induced a major downregulation of placental transcripts related to immune processes such as T-cell regulation, interleukin and cytokine signaling, or innate immune responses. Expression differences of main immune-related genes, such as CD46, CD15, CD8 alpha & beta ILR7 alpha, and CCR4 among others, were found in the Index group (P < 0.05). Moreover, the key immune-like pathway involved in humoral and cellular immunity named "Primary immunodeficiency" was significantly downregulated in the Index group compared with Controls. Our results show that mechanisms ruling immune system functions are compromised at the maternal-fetal interface following self-perceived depressive symptoms and anxiety during pregnancy. These findings may help unveil mechanisms ruling the impact of maternal psychiatric symptoms and lead to new prevention/intervention strategies in complicated pregnancies. Summary Sentence Mechanisms ruling immune system functions are compromised at the maternal-fetal interface following self-perceived depressive symptoms and anxiety during pregnancy.
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47. |
- Mohseni, Simin, 1959-, et al.
(författare)
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Hypoglycaemic neuropathy : Occurrence of axon terminals in plantar skin and plantar muscle of diabetic BB/Wor rats treated with insulin implants
- 2000
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Ingår i: Acta Neuropathologica. - 0001-6322 .- 1432-0533. ; 99:3, s. 257-262
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Tidskriftsartikel (refereegranskat)abstract
- It is generally believed that diabetic neuropathy is due to chronic hyperglycaemia. However, experience from insulinoma patients and experimental studies show that hypoglycaemia may also cause neuropathy. Accordingly, the plantar nerves of diabetic eu-/hypoglycaemic BB/Wor rats treated with insulin implants exhibit a distinct neuropathy. To what extent hypoglycaemic neuropathy affects axon terminals in skin and muscle is unknown. In the present study we examine the occurrence of epidermal axon profiles and the neuropeptide calcitonin gene-related peptide (CGRP) in plantar skin, and of end plate axon terminals in a plantar muscle of diabetic BB/Wor rats subjected to long periods of hypoglycaemia. The number of protein gene product-immunoreactive axon profiles was found to be normal in heel skin biopsy specimens from eu-/hypoglycaemic rats, but many profiles were short and thin. The content of CGRP in the skin biopsy samples was significantly below normal. After staining with antibodies against the vesicular acetylcholine transporter protein, the occurrence of end plate axon terminals was significantly reduced in sections from the flexor hallucis brevis muscle of eu-/hypoglycaemic rats. Moreover, the end plate axon terminals tended to be abnormally small in these rats. We conclude that the hypoglycaemic neuropathy seen in plantar nerve trunks of diabetic BB/Wor rats treated with insulin implants is accompanied by mild alterations in the epidermal innervation of plantar skin and a more obviously abnormal nerve terminal pattern in plantar muscle.
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48. |
- Mörelius, Evalotte, 1965-, et al.
(författare)
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OC09 - Early maternal contact has an impact on preterm infants' brain systems that manage stress.
- 2016
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Ingår i: Nursing children and young people. - London, Middx, United Kingdom : RCNi. - 2046-2344 .- 2046-2336. ; 28:4, s. 62-63
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Tidskriftsartikel (refereegranskat)abstract
- UNLABELLED: Theme: Parenting/parenthood.INTRODUCTION: Early maternal contact can protect the infants' brain from harmful effects of stress while deprivation increases the stress level and leads to increased sensitivity to stress.AIM: To evaluate the effects of continuous skin-to-skin contact (SSC) after preterm birth on stress.METHODS: Late preterm infants from two neonatal care units were randomized to either SSC or standard care. Salivary cortisol was measured in response to a nappy change at one month, and again at four months in response to a still-face procedure.RESULTS: Infants randomized to SSC had a significantly lower salivary cortisol reactivity at one month and there was a correlation between the mothers' and the preterm infants' salivary cortisol levels at four months.CONCLUSIONS: The results show that close parental contact and human touch have a buffering effect on the infant's stress reactivity and stimulate a more rapid development of regularity.
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49. |
- Preinbergs, Julia, 1989-, et al.
(författare)
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Effect of cosmetic hair treatment and natural hair colour on hair testosterone concentrations
- 2023
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 18:10
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Tidskriftsartikel (refereegranskat)abstract
- PurposeTestosterone analysis in hair allows for retrospective evaluation of endogenous testosterone concentrations, but studies devoted to investigating confounders in hair testosterone analysis have hitherto been scarce. The current study examined the stability of testosterone concentrations between two hair samples collected three months apart and investigated two potential confounding factors: natural hair colour and cosmetic hair treatments.MethodsTestosterone was analysed with an in-house radioimmunoassay with a limit of detection adequate for the purpose.ResultsThe testosterone concentrations from the two samplings, at baseline and three months later, had an intra-individual correlation of moderate strength (rho = 0.378, p<0.001, n = 146). Hair treatment, such as colouring or bleaching, seemed to increase testosterone concentrations (p = 0.051, n = 191, and in a paired analysis in a subset of the cohort p = 0.005, n = 24), while no effect of natural colour in untreated hair (p = 0.133) could be detected.ConclusionThe current results suggest that cosmetic hair treatments need to be considered in hair testosterone analyses and demonstrate the utility of a radioimmunoassay to reliably measure testosterone concentrations in small hair samples in women.
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50. |
- 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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