17 results on '"Stein Frostad"'
Search Results
2. Are the Effects of Malnutrition on the Gut Microbiota–Brain Axis the Core Pathologies of Anorexia Nervosa?
- Author
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Stein Frostad
- Subjects
anorexia nervosa ,anxiety ,gut microbiota–brain axis ,Biology (General) ,QH301-705.5 - Abstract
Anorexia nervosa (AN) is a disabling, costly, and potentially deadly illness. Treatment failure and relapse after treatment are common. Several studies have indicated the involvement of the gut microbiota–brain (GMB) axis. This narrative review hypothesizes that AN is driven by malnutrition-induced alterations in the GMB axis in susceptible individuals. According to this hypothesis, initial weight loss can voluntarily occur through dieting or be caused by somatic or psychiatric diseases. Malnutrition-induced alterations in gut microbiota may increase the sensitivity to anxiety-inducing gastrointestinal hormones released during meals, one of which is cholecystokinin (CCK). The experimental injection of a high dose of its CCK-4 fragment in healthy individuals induces panic attacks, probably via the stimulation of CCK receptors in the brain. Such meal-related anxiety attacks may take part in developing the clinical picture of AN. Malnutrition may also cause increased effects from appetite-reducing hormones that also seem to have roles in AN development and maintenance. The scientific background, including clinical, microbiological, and biochemical factors, of AN is discussed. A novel model for AN development and maintenance in accordance with this hypothesis is presented. Suggestions for future research are also provided.
- Published
- 2022
- Full Text
- View/download PDF
3. Implementation of enhanced cognitive behaviour therapy (CBT-E) for adults with anorexia nervosa in an outpatient eating-disorder unit at a public hospital
- Author
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Stein Frostad, Yngvild S. Danielsen, Guro Å. Rekkedal, Charlotte Jevne, Riccardo Dalle Grave, Øyvind Rø, and Ute Kessler
- Subjects
Anorexia nervosa ,Adults ,Cognitive behaviour therapy ,Body mass index ,Psychiatry ,RC435-571 - Abstract
Abstract Background Anorexia nervosa (AN) in adults is difficult to treat, and no current treatment is supported by robust evidence. A few studies, most of which were performed by highly specialized research units, have indicated that enhanced cognitive behaviour therapy (CBT-E) for eating disorders can be effective. However, the dropout rate is high and the evidence from non-research clinical units is sparse. Methods This quality assessment project implemented CBT-E in an outpatient setting at a public hospital. Forty-four patients with AN started therapy. Each patient received at least 40 sessions of CBT-E over a 12-month period. Their body mass index (BMI) was recorded at baseline and after 3, 6 and 12 months. Reasons for not starting therapy or for leaving therapy prematurely were recorded. Results Half (n = 22) of the 44 patients who started outpatient CBT-E did not complete the treatment. In the remaining sample there was a large (and statistically significant) weight gain after 12 months. The percentage of patients achieving the target BMI of > 18.5 kg/m2 was 36.4, 50.0 and 77.3% after 3, 6 and 12 months, respectively. Conclusions This quality assessment project shows that it is possible to establish effective CBT-E in an outpatient eating-disorder unit at a public hospital. Although half of the patients did not complete CBT-E, the remaining patients achieved a significant increase in BMI at 1 year after the start of therapy.
- Published
- 2018
- Full Text
- View/download PDF
4. Effectiveness of enhanced cognitive behavioral therapy (CBT-E) in the treatment of anorexia nervosa: a prospective multidisciplinary study
- Author
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Yngvild S. Danielsen, Guro Årdal Rekkedal, Stein Frostad, and Ute Kessler
- Subjects
Anorexia nervosa ,Enhanced cognitive behavioral therapy ,CBT-E ,Treatment dropout ,Gut microbiota ,Genetics ,Psychiatry ,RC435-571 - Abstract
Abstract Background Anorexia nervosa (AN) is a debilitating psychiatric disorder associated with a wide array of negative health complications and psychiatric comorbidity. Existing evidence for AN treatment in adults is weak, and no empirically supported treatment has been reliably established. The primary objective of this study is to gain knowledge about the effectiveness of enhanced cognitive behavioral therapy (CBT-E) for anorexia nervosa delivered in a public hospital setting. Baseline predictors of treatment outcome and dropout are studied. Furthermore, there will be collected blood and stool samples for a general biobank to be able to initiate research on possible pathophysiological mechanisms underlying AN. Methods The study will assess the potency of outpatient CBT-E in a sample of patients suffering from AN (age >16) admitted to the Section for Eating Disorders at the Department for Psychosomatic Medicine, Haukeland University Hospital in Bergen, Norway. The study has a longitudinal design with five main assessment time points: before treatment, at 3 months, at the end of treatment, at 20 weeks, and at 12 months follow-up including biobank samples. A control group without an eating disorder will also be recruited. Discussion Treatment research in a public hospital setting is important for gaining knowledge about the transportability of treatments evaluated in research clinics into ordinary clinical practice. Furthermore, biological material from the thoroughly described patient cohort will serve as a basis for further research on the pathophysiological mechanisms in AN. Trial registration ClinicalTrials.gov Identifier: NCT02745067 . Registered 14 April 2016.
- Published
- 2016
- Full Text
- View/download PDF
5. Anorexia nervosa: Outpatient treatment and medical management
- Author
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Stein Frostad and Mette Bentz
- Abstract
Anorexia nervosa (AN) is a disabling, costly and potentially deadly illness. Treatment failure and relapse are common after completing treatment, and a substantial proportion of patients develop severe and enduring AN. The time from AN debut to the treatment initiation is normally unreasonably long. Over the past 20 years there has been empirical support for the efficacy of several treatments for AN. Moreover, outpatient treatment with family-based therapy or individual psychotherapy is associated with good outcomes for a substantial proportion of patients. Early intervention improves outcomes and should be a priority for all patients. Outpatient treatment is usually the best format for early intervention, and it has been demonstrated that even patients with severe or extreme AN can be treated as outpatients if they are medically stable. Inpatient care is more disruptive, more costly, and usually has a longer waiting list than does outpatient care. The decision as to whether to proceed with outpatient treatment or to transfer the patient for inpatient therapy may be difficult. The core aim of this opinion review is to provide the knowledge base needed for performing safe outpatient treatment of AN. The scientific essentials for outpatient treatment are described, including how to assess and manage the medical risks of AN and how to decide when transition to inpatient care is indicated. The following aspects are discussed: early intervention, outpatient treatment of AN, including outpatient psychotherapy for severe and extreme AN, how to determine when outpatient treatment is safe, and when transfer to inpatient healthcare is indicated. Emerging treatments, ethical issues and outstanding research questions are also addressed.
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- 2022
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6. BMI at Discharge from Treatment Predicts Relapse in Anorexia Nervosa: A Systematic Scoping Review
- Author
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Stein Frostad, Natalia Rozakou-Soumalia, Ştefana Dârvariu, Bahareh Foruzesh, Helia Azkia, Malina Ploug Larsen, Ehsan Rowshandel, and Jan Magnus Sjögren
- Subjects
Medicine (miscellaneous) - Abstract
Background: Anorexia nervosa (AN) has high rates of enduring disease and mortality. Currently, there is insufficient knowledge on the predictors of relapse after weight normalization and this is why a systematic literature review was performed. Methods: PubMed, EMBASE, PsychInfo, and Cochrane databases were searched for literature published until 13 July 2021. All study designs were eligible for inclusion if they focused on predictors of relapse after weight normalization in AN. Individual study definitions of relapse were used, and in general, this was either a drop in BMI and/or reccurrence of AN symptoms. Results: The database search identified 11,507 publications, leaving 9511 publications after the removal of duplicates and after a review of abstracts and titles; 191 were selected for full-text review. Nineteen publications met the criteria and included 1398 AN patients and 39 healthy controls (HC) from adults and adolescents (ages range 11–73 years). The majority used a prospective observational study design (12 studies), a few used a retrospective observational design (6 studies), and only one was a non-randomized control trial (NRCT). Sample sizes ranged from 16 to 191 participants. BMI or measures of body fat and leptin levels at discharge were the strongest predictors of relapse with an approximate relapse rate of 50% at 12 months. Other predictors included signs of eating disorder psychopathology at discharge. Conclusions: BMI at the end of treatment is a predictor of relapse in AN, which is why treatment should target a BMI well above 20. Together with the time to relapse, these outcomes are important to include in the evaluation of current and novel treatments in AN and for benchmarking. BACKGROUND: Anorexia nervosa (AN) has high rates of enduring disease and mortality. Currently, there is insufficient knowledge on the predictors of relapse after weight normalization and this is why a systematic literature review was performed.METHODS: PubMed, EMBASE, PsychInfo, and Cochrane databases were searched for literature published until 13 July 2021. All study designs were eligible for inclusion if they focused on predictors of relapse after weight normalization in AN. Individual study definitions of relapse were used, and in general, this was either a drop in BMI and/or reccurrence of AN symptoms.RESULTS: The database search identified 11,507 publications, leaving 9511 publications after the removal of duplicates and after a review of abstracts and titles; 191 were selected for full-text review. Nineteen publications met the criteria and included 1398 AN patients and 39 healthy controls (HC) from adults and adolescents (ages range 11-73 years). The majority used a prospective observational study design (12 studies), a few used a retrospective observational design (6 studies), and only one was a non-randomized control trial (NRCT). Sample sizes ranged from 16 to 191 participants. BMI or measures of body fat and leptin levels at discharge were the strongest predictors of relapse with an approximate relapse rate of 50% at 12 months. Other predictors included signs of eating disorder psychopathology at discharge.CONCLUSIONS: BMI at the end of treatment is a predictor of relapse in AN, which is why treatment should target a BMI well above 20. Together with the time to relapse, these outcomes are important to include in the evaluation of current and novel treatments in AN and for benchmarking.
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- 2022
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7. Enhanced cognitive behavior therapy for severe and extreme anorexia nervosa: An outpatient case series
- Author
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Stein Frostad, Riccardo Dalle Grave, Massimiliano Sartirana, and Simona Calugi
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Pediatrics ,medicine.medical_specialty ,Depressive Disorder, Major ,Anorexia Nervosa ,Cognitive Behavioral Therapy ,business.industry ,Cognition ,Eating disorder examination questionnaire ,medicine.disease ,Substance abuse ,Psychiatry and Mental health ,Treatment Outcome ,Anorexia nervosa (differential diagnoses) ,Outpatients ,medicine ,Outpatient setting ,Ambulatory Care ,Humans ,In patient ,medicine.symptom ,business ,Body mass index ,Weight gain - Abstract
OBJECTIVE The study aimed to assess outcomes in patients with severe and extreme anorexia nervosa managed with enhanced cognitive behavior therapy (CBT-E) in a real-world outpatient setting. METHOD Thirty patients with anorexia nervosa and body mass index (BMI)
- Published
- 2020
8. Dysbiosis of the Microbiota in Anorexia Nervosa: Pathophysiological Implications
- Author
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Stein Frostad, Magnus Sjögren, and Kenneth Klingenberg Barfod
- Subjects
Anorexia nervosa (differential diagnoses) ,InformationSystems_INFORMATIONSTORAGEANDRETRIEVAL ,Immunology ,medicine ,Biology ,medicine.disease ,GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries) ,Dysbiosis ,Pathophysiology - Published
- 2019
- Full Text
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9. Effectiveness of enhanced cognitive behavioral therapy (CBT-E) in the treatment of anorexia nervosa: a prospective multidisciplinary study
- Author
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G. Rekkedal, Ute Kessler, Stein Frostad, and Yngvild Sørebø Danielsen
- Subjects
Adult ,Male ,050103 clinical psychology ,medicine.medical_specialty ,lcsh:RC435-571 ,medicine.medical_treatment ,Enhanced cognitive behavioral therapy ,Disease ,Gut microbiota ,Study Protocol ,03 medical and health sciences ,0302 clinical medicine ,Multidisciplinary approach ,lcsh:Psychiatry ,medicine ,Genetics ,Humans ,0501 psychology and cognitive sciences ,CBT-E ,Longitudinal Studies ,Prospective Studies ,Prospective cohort study ,Psychiatry ,Depression (differential diagnoses) ,Cognitive Behavioral Therapy ,Norway ,business.industry ,05 social sciences ,Neuropsychology ,Psychosomatic medicine ,Anorexia nervosa ,medicine.disease ,Biobank ,030227 psychiatry ,Cognitive behavioral therapy ,Psychiatry and Mental health ,Eating disorders ,Treatment Outcome ,Anorexia nervosa (differential diagnoses) ,Cohort ,Cognitive therapy ,Anxiety ,Female ,Treatment dropout ,medicine.symptom ,business ,Psychology ,Clinical psychology - Abstract
IntroductionAccording to the most widely influential treatment guidelines from the National Institute for Health and Clinical Excellence and the American Psychiatric Association, existing evidence for adult AN treatment is weak, and more treatment studies are needed.Objectives/aimsThe primary objective of this project is to gain knowledge about the effectiveness of CBT-E in the treatment of Anorexia Nervosa (AN). Secondary objectives are to prospectively examine baseline predictors of treatment outcome/drop-out and to examine variables related to treatment process and patient engagement as predictors of outcome/drop-out. Thirdly, in a multidisciplinary approach, to focus on selected pathophysiological mechanisms including disturbed neuropsychological functioning, changes in the gut microbiota, immunological and genetic measures in patients with severe AN in different stages of the disease, and further to investigate to what extent they are related to treatment outcome.MethodsThe sample consists of patients aged ≥ 16 years with AN admitted to outpatient treatment (CBT-E) at Section for Eating Disorders, Haukeland University Hospital, Bergen, Norway. Outcome measures include BMI, self-reported eating disorder symptoms (EDE-Q), depression (BDI), anxiety (BAI) general psychiatric symptomatology (SCL-90-R, M.I.N.I 6.0), health related quality of life (CIA, RAND-36), physical activity (accelerometers) and neuropsychological functioning. The main measurement points are at the start of treatment, 3 months, end of treatment and one year follow-up. Baseline predictors of treatment outcome and drop-out will be examined as well as the association between early adherence, behavioral change, therapeutic alliance and treatment outcome. In addition biochemical, genetic and bacteriological assessments will be conducted.Disclosure of interestThe authors have not supplied their declaration of competing interest.
- Published
- 2016
- Full Text
- View/download PDF
10. Implementation of enhanced cognitive behaviour therapy (CBT-E) for adults with anorexia nervosa in an outpatient eating-disorder unit at a public hospital
- Author
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Charlotte Jevne, Øyvind Rø, Stein Frostad, Ute Kessler, G. Rekkedal, Yngvild Sørebø Danielsen, and Riccardo Dalle Grave
- Subjects
050103 clinical psychology ,medicine.medical_specialty ,lcsh:RC435-571 ,Anorexia nervosa ,behavioral disciplines and activities ,03 medical and health sciences ,Behavioral Neuroscience ,0302 clinical medicine ,lcsh:Psychiatry ,medicine ,Outpatient setting ,Adults ,0501 psychology and cognitive sciences ,Letter to the Editor ,Body mass index ,Nutrition and Dietetics ,business.industry ,Quality assessment ,Cognitive behaviour therapy ,05 social sciences ,medicine.disease ,030227 psychiatry ,Psychiatry and Mental health ,Eating disorders ,Public hospital ,Physical therapy ,medicine.symptom ,business ,Weight gain - Abstract
Background Anorexia nervosa (AN) in adults is difficult to treat, and no current treatment is supported by robust evidence. A few studies, most of which were performed by highly specialized research units, have indicated that enhanced cognitive behaviour therapy (CBT-E) for eating disorders can be effective. However, the dropout rate is high and the evidence from non-research clinical units is sparse. Methods This quality assessment project implemented CBT-E in an outpatient setting at a public hospital. Forty-four patients with AN started therapy. Each patient received at least 40 sessions of CBT-E over a 12-month period. Their body mass index (BMI) was recorded at baseline and after 3, 6 and 12 months. Reasons for not starting therapy or for leaving therapy prematurely were recorded. Results Half (n = 22) of the 44 patients who started outpatient CBT-E did not complete the treatment. In the remaining sample there was a large (and statistically significant) weight gain after 12 months. The percentage of patients achieving the target BMI of > 18.5 kg/m2 was 36.4, 50.0 and 77.3% after 3, 6 and 12 months, respectively. Conclusions This quality assessment project shows that it is possible to establish effective CBT-E in an outpatient eating-disorder unit at a public hospital. Although half of the patients did not complete CBT-E, the remaining patients achieved a significant increase in BMI at 1 year after the start of therapy.
- Published
- 2018
11. Insulin-like Growth Factor-1 (IGF-1) is a Costimulator of the Expansion of Lineage Committed Cells Derived from Peripheral Blood Mobilized CD34(+) Cells in Multiple Myeloma Patients
- Author
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Øystein Bruserud, Tor Hervig, Stein Frostad, Robert Bjerknes, Ingerid Nesthus, and Johanna Olweus
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medicine.medical_specialty ,medicine.medical_treatment ,CD34 ,Stem cell factor ,Hematology ,CD15 ,Granulocyte ,Biology ,Colony-stimulating factor ,Molecular biology ,In vitro ,03 medical and health sciences ,Insulin-like growth factor ,0302 clinical medicine ,medicine.anatomical_structure ,Endocrinology ,030225 pediatrics ,030220 oncology & carcinogenesis ,Internal medicine ,medicine ,Progenitor cell - Abstract
The effect of insulin-like growth factor-1 (IGF-1) on highly enriched human apheresis CD34(+) progenitor cells was investigated in vitro. The progenitor cells were mobilized by treatment with cyclophosphamide + granulocyte - colony stimulating factor (G-CSF) in patients with multiple myeloma. CD34(+) cells were cultured for 7 days in serumfree medium containing stem cell factor (SCF), granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin-3 (IL-3), and this is referred to as cytokine-dependent proliferation. After 7 days of cytokine-dependent proliferation the total number of viable cells increased 1.6-8.2 times, and subsets of cells expressing the granulocyte marker CD15, the myelomonocytic marker CD64 and the erythrocyte phenotype CD71(high) /CD64(-) were detected among the in vitro cultured cells. Addition of G-CSF together with SCF + IL-3 + GM-CSF increased the number of CD15(+) and CD64(+) cells, but without altering the number of erythroid cells. IGF-1 caused a dose-dependent increase in the number of CD15(+), CD64(+) and CD71(high) /CD64(-) cells, and this increase was detected when cells were cultured in both SCF + IL-3 + GM-CSF alone and G-CSF + SCF + IL-3 + GM-CSF. A minor subset of CD34(+) cells could still be detected among in vitro cultured cells and the number of CD34(+) cells was not altered by adding G-CSF and/or IGF-1. Morphologically recognizable mature granulocytes or erythroid cells could not be detected for any of the combinations investigated. We conclude that IGF-1 can enhance the in vitro proliferation of committed progenitor cells derived from apheresis CD34(+) cells.
- Published
- 2016
12. THE ONTOGENY OF IMMUNOLOGICAL RECEPTORS IN THE THYMUS
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Nils Erik Gilhus, Roald Matre, Olav Tönder, and Stein Frostad
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Pathology ,medicine.medical_specialty ,Erythrocytes ,Immunology ,Fc receptor ,Receptors, Fc ,Thymus Gland ,Complement receptor ,Immune receptor ,Fetus ,Pregnancy ,Cortex (anatomy) ,medicine ,Animals ,Humans ,Receptors, Immunologic ,Child ,Receptor ,Medulla ,Sheep ,General Immunology and Microbiology ,biology ,Receptors, IgG ,Infant ,General Medicine ,Receptors, Complement ,medicine.anatomical_structure ,Immunoglobulin M ,Child, Preschool ,Receptors, Complement 3b ,biology.protein ,Female ,Receptors, Complement 3d - Abstract
Receptors for sheep erythrocytes, for the Fc part of IgG (Fc gamma R) and IgM (Fc mu R), and for components of activated human complement C3 (C3bR and C3dR) in thymus tissue from fetuses, infants and children were studied using haemadsorption to cryostat sections in a closed chamber. Sheep erythrocytes (SE) did not adhere to sections of thymus from fetuses at 10-11 weeks of gestation, adhered weakly between 14 and 20 weeks, while they adhered in a dense monolayer in older fetuses, in infants and in children, denser in the cortex than in the medulla. Ox erythrocytes (OE), sensitized with IgG to demonstrate Fc gamma R, adhered focally to both cortical and medullary areas. The adherence was more pronounced to the sections of fetal thymus than to the sections from infants and children. OE, sensitized with IgM to demonstrate Fc mu R, adhered focally to all thymus tissue sections, preferentially to the cortex. The adherence was most pronounced in fetal thymus. SE, sensitized with IgM and coated with complement, adhered to sections of fetal thymus, but the density decreased markedly during fetal life. Indicator cells demonstrating C3bR adhered focally also to sections from infants and children, while indicator cells demonstrating C3dR did not adhere to sections from individuals older than 38 weeks of gestation. Indicator cells demonstrating C3bR and C3dR adhered both to cortex and medulla.
- Published
- 2009
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13. [Somatic investigation and treatment of eating disorders]
- Author
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Stein, Frostad
- Subjects
Feeding and Eating Disorders ,Male ,Anorexia Nervosa ,Heart Diseases ,Bone Density ,Risk Factors ,Malnutrition ,Humans ,Female ,Comorbidity ,Growth Disorders ,Hypoglycemia - Abstract
Eating disorders are associated with several medical complications. Growth retardation and osteoporosis can cause permanent sequelae if treatment is delayed. Severe eating disorders are associated with significant mortality. Cardiac arrhythmias are the most common somatic cause of death. Hypokalaemia is a common complication and is associated with increased risk of cardiac arrhythmias. Occasionally, overzealous refeeding may induce a potentially life-threatening condition, the refeeding syndrome. In any patient with severe eating disorder, a physician should perform diagnostic evaluation including assessment of possible somatic complications. This is necessary in order to determine where and how the patient should be treated. Most of the somatic complications of eating disorders are partly or completely reversible if the patient receives adequate treatment in time.
- Published
- 2004
14. Malignancy: Insulin-like Growth Factor-1 (IGF-1) is a Costimulator of the Expansion of Lineage Committed Cells Derived from Peripheral Blood Mobilized CD34+ Cells in Multiple Myeloma Patients
- Author
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STEIN, Frostad, ROBERT, Bjerknes, TOR, Hervig, INGERID, Nesthus, JOHANNA, Olweus, and ØYSTEIN, Bruserud Ø
- Abstract
The effect of insulin-like growth factor-1 (IGF-1) on highly enriched human apheresis CD34(+) progenitor cells was investigated in vitro. The progenitor cells were mobilized by treatment with cyclophosphamide + granulocyte - colony stimulating factor (G-CSF) in patients with multiple myeloma. CD34(+) cells were cultured for 7 days in serumfree medium containing stem cell factor (SCF), granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin-3 (IL-3), and this is referred to as cytokine-dependent proliferation. After 7 days of cytokine-dependent proliferation the total number of viable cells increased 1.6-8.2 times, and subsets of cells expressing the granulocyte marker CD15, the myelomonocytic marker CD64 and the erythrocyte phenotype CD71(high) /CD64(-) were detected among the in vitro cultured cells. Addition of G-CSF together with SCF + IL-3 + GM-CSF increased the number of CD15(+) and CD64(+) cells, but without altering the number of erythroid cells. IGF-1 caused a dose-dependent increase in the number of CD15(+), CD64(+) and CD71(high) /CD64(-) cells, and this increase was detected when cells were cultured in both SCF + IL-3 + GM-CSF alone and G-CSF + SCF + IL-3 + GM-CSF. A minor subset of CD34(+) cells could still be detected among in vitro cultured cells and the number of CD34(+) cells was not altered by adding G-CSF and/or IGF-1. Morphologically recognizable mature granulocytes or erythroid cells could not be detected for any of the combinations investigated. We conclude that IGF-1 can enhance the in vitro proliferation of committed progenitor cells derived from apheresis CD34(+) cells.
- Published
- 2001
15. In vitro culture of acute myelogenous leukemia blasts: a comparison of four different culture media
- Author
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Øystein Bruserud, Brynjar Foss, and Stein Frostad
- Subjects
Adult ,CD4-Positive T-Lymphocytes ,Male ,Cell Survival ,medicine.medical_treatment ,T cell ,Immunology ,Cell Culture Techniques ,Biology ,Lymphocyte Activation ,Culture Media, Serum-Free ,hemic and lymphatic diseases ,medicine ,Tumor Cells, Cultured ,Humans ,Secretion ,Antigen-presenting cell ,Aged ,Aged, 80 and over ,Hematology ,Middle Aged ,medicine.disease ,Molecular biology ,Coculture Techniques ,Leukemia ,Leukemia, Myeloid, Acute ,Cytokine ,medicine.anatomical_structure ,Gamma Rays ,Cytokines ,Tumor necrosis factor alpha ,Cytokine secretion ,Female ,Fetal bovine serum ,Cell Division - Abstract
Proliferative responses and cytokine secretion were compared when AML blasts were cultured in the three serum-free media, X-Vivo 10, X-Vivo 15, and defined serum-free medium (IMDM with mercaptoethanol, low-density lipoprotein, albumin, and transferrin) and in media containing 10% inactivated fetal bovine serum (FBS). The following AML blast functions were investigated: (a) constitutive cytokine secretion, (b) autonomous and cytokine-dependent proliferation, and (c) accessory cell function during T cell activation. Constitutive cytokine secretion and accessory cell function differed markedly when using different culture media. For the constitutive AML blast secretion of IL-1beta, IL-6, and tumor necrosis factor (TNF)-alpha, no qualitative differences were seen, but quantitative differences were observed with decreased cytokine levels for cells cultured in X-Vivo 10 and X-Vivo 15. The accessory cell function of AML blasts was also decreased in the X-Vivo media, whereas differences were less pronounced when comparing AML blast proliferation. Our results clearly demonstrate that a well-characterized culture system is essential for in vitro studies of AML blast functions.
- Published
- 1999
16. Insulin-like growth factor-1 (IGF-1) has a costimulatory effect on proliferation of committed progenitors derived from human umbilical cord CD34+ cells
- Author
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Øystein Bruserud, Robert Bjerknes, Stein Frostad, J. F. Abrahamsen, and Johanna Olweus
- Subjects
CD3 Complex ,medicine.medical_treatment ,CD34 ,Stem cell factor ,Antigens, CD34 ,Biology ,Umbilical cord ,Culture Media, Serum-Free ,Flow cytometry ,Insulin-like growth factor ,Antigen ,Antigens, CD ,Granulocyte Colony-Stimulating Factor ,Receptors, Transferrin ,medicine ,Humans ,Progenitor cell ,Insulin-Like Growth Factor I ,Cells, Cultured ,medicine.diagnostic_test ,Cell growth ,Stem Cells ,Infant, Newborn ,Cell Differentiation ,Cell Biology ,Fetal Blood ,Flow Cytometry ,Molecular biology ,Antigens, Differentiation, B-Lymphocyte ,medicine.anatomical_structure ,Immunology ,Molecular Medicine ,Cytokines ,Cell Division ,Developmental Biology - Abstract
The effects of insulin-like growth factor-1 (IGF-1) on highly enriched human umbilical cord CD34+ cells were investigated in vitro. CD34+ cells were cultured in serum-free medium containing stem cell factor (SCF), GM-CSF, and interleukin-3 (IL-3). Culture of CD34+ cells for one week in the presence of these cytokines resulted in a dose-dependent increase in total cell number. Addition of G-CSF together with SCF+IL-3+GM-CSF increased the proliferation of myelopoietic cells as determined by the number of cells expressing the myelomonocytic marker CD64 and the granulocytic marker CD15 without significantly altering the number of CD34+ cells in the cultures. In the presence of G-CSF, IGF-1 induced a dose-dependent increase in the total cell number and a moderate but significant increase in the percentages of CD15+, CD64+ cells with sustained CD34+ cell proliferation. We conclude that IGF-1 can enhance the in vitro proliferation of committed progenitor cells derived from umbilical cord CD34+ cells.
- Published
- 1998
17. The sequence of the hemoregulatory peptide is present in Gi alpha proteins
- Author
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Stein Frostad, Dietmar Kamp, Hege I. Tøn, and Ole Didrik Laerum
- Subjects
G-protein ,G protein ,Molecular Sequence Data ,Biophysics ,Peptide ,Biology ,In Vitro Techniques ,Biochemistry ,Mice ,Structure-Activity Relationship ,GTP-binding protein regulators ,Structural Biology ,GTP-Binding Proteins ,Genetics ,Animals ,Amino Acid Sequence ,Hemoregulatory peptide ,Molecular Biology ,Peptide sequence ,chemistry.chemical_classification ,Oligopeptide ,Effector ,Cell Biology ,Hematopoiesis ,Pyrrolidonecarboxylic Acid ,chemistry ,Hemopoiesis ,Signal transduction ,Sequence motif ,Oligopeptides - Abstract
The hemoregulatory peptide PyroGlu-Glu-Asp-Cys-Lys (HP5b), which inhibits myelopoietic colony formation in vitro, is shown to be a sequence motif which is also part of the effector domain of Gi alpha proteins. Out of 8 synthetic peptides with sequence variations of HP5b, those with the closest similarity to the Gi alpha sequence are biologically active. The inhibitory effect appears to be dependent on the blocked N-terminus. It is postulated that these peptides may interfere with signal transduction mediated by Gi alpha proteins.
- Published
- 1990
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