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| 2. |
- Brundin, Peik M. A., 1975-
(författare)
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Sex differences in immune response and sex hormone receptor expression in healthy individuals and during viral infection
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- There is sex-bias in morbidity and mortality from infectious diseases. Infections kill more men than women and several studies have pointed out differences in the immune system as a reason. The sex hormones estrogen, progesterone and testosterone all shape the effect of the immune response on multiple levels. Women at fertile age have been suggested to have higher proinflammatory responses from inflammatory stimuli compared to men and post-menopausal women, which has been ascribed to their higher estrogen levels. This could possibly lead to a more active pathogen response but may also result in a detrimental immunopathology to infections or development of autoimmune reaction.The overall aim of this thesis is to study the contribution of sex hormones and sex hormone receptors (SHR) to sex differences in immune response. We focus on peripheral blood mononuclear cells (PBMCs) to study such relationships in healthy individuals, as well as in individuals with asymptomatic Torque Teno Virus infection, and individuals with acute Puumala virus infection.In Paper I, we investigated expression of SHR and immune response genes in PBMC from healthy premenopausal (pre-MP) women during the menstrual cycle. The expression levels were estimated using a qPCR Array (Taqman low-density array, TLDA). SHR expression did not change significantly during the menstrual cycle, but several key immune regulatory genes were significantly more expressed during the ovulatory and mid luteal phase. Further, we separated PBMC into cell subsets (CD4+ T-cells, CD8+ T-cells, CD56+ NK-cells, CD14+ monocytes and CD19+ B-cells) and analyzed the expression through qPCR of estrogen receptors (ERs), ERα, ERβ1 (wildtype) and the isoform ERβ2. For the first time and unexpectedly, we demonstrate that the isoform ERβ2 was more abundant than wildtype ERβ1. The data from this paper provides new knowledge on the contribution of the menstrual cycle on immune response.In Paper II, we explored the use of Torque Teno Virus as a secondary functional immune marker in men and women. Expression of viral TTV DNA in PBMCs was estimated using a qPCR kit from Argene (R-gene) and analyzed in relation to serum sex hormone levels. The results showed that 50% of the men, 25% the post-MP women, and 18% of the pre-MP women were TTV+. Interestingly, all pre-MP women that were TTV+ had hormonal aberrances and were either anovulatory and/or hypothyroid. TTV+ pre-MP women also had significantly lower progesterone levels than TTV- pre-MP women. This paper indicates that the prevalence of TTV in PBMC differs between men, pre-MP and post-MP women. Furthermore, hormonal aberrances (at least in pre-MP women) will lead to increased prevalence of TTV.In Paper III we investigated the expression of ERα, ERβ1 and ERβ2 in PBMC from patients with Nephropathia epidemica, the viral zoonotic disease caused by Puumala virus, a Hanta virus known to affect more men than women. Expression of ERs in PBMCs and clinical laboratory results during the acute and convalescent phases were analyzed using a principal component analysis (PCA). The results show differences in ER expression and support previous findings that men and women have a different clinical pictureIn conclusion, the results in this thesis reveal distinct patterns of immune response related to sex hormone levels, SHR expression and the phases of the menstrual cycle supporting that there a link between sex hormone levels and immune responses. Further, we show that the ER isoform ERβ2 is more abundant in PBMCs than what was previously described. The data in this thesis adds to the knowledge to the sex differences in immune response and exemplifies the importance of taking these differences into account in the clinic.
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| 3. |
- Björkman, Kristoffer, et al.
(författare)
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Clinical course of patients with single large-scale mtDNA deletions and childhood onset anemia
- 2022
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Ingår i: 14th European Paediatric Neurology Society Congress, Glasgow, UK (ISBN 978-3-00-072065-9).
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Objective: To add to our knowledge of the clinical spectrum of patients with single large-scale mitochondrial DNA (mtDNA) deletion and childhood onset anemia. Methods: Retrospective collection of clinical data from medical records for patients, both living and deceased, with a single large-scale mtDNA deletion from seven mitochondrial disease centers in five countries. Statistical analysis with descriptive methods and Kaplan-Meier survival analysis. Results: Seventeen patients matching the genetic criterium and with anemia onset before six years of age. Exocrine pancreatic insufficiency was only seen in five patients in this group. Multiple organs were involved in all patients, with the most common non-hematologic ones being skeletal muscle, central nervous system, endocrine, eyes, gastrointestinal system, kidneys, hearing, liver and heart. Psychomotor retardation was seen in ten patients, hearing impairment in nine patients, failure to thrive in eight patients. Eight later developed Kearns-Sayre syndrome. Eleven patients were deceased, with a median age at death of 7.5 years. Conclusions: The classically described phenotype of patients with large-scale mtDNA deletions and early onset anemia is Pearson marrow-pancreas syndrome, characterized by sideroblastic anemia and exocrine pancreas dysfunction. Only a minority of our patients fulfill the original criteria of Pearson syndrome though. Involvement of other organs than the pancreas is more common. The clinical course vary, but multi-system impact is the rule and life-expectancy is low. Early onset anemia in patients with large-scale mtDNA deletions is most frequently not associated with exocrine pancreas dysfunction. Better knowledge of the phenotype is helpful for diagnosis and more accurate prognosis.
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| 4. |
- Löfgren, Magnus, 1979-
(författare)
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Behavioral effects of female sex steroid hormones : models of PMS and PMDD in Wistar rats
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background Animal models can be used to mimic human conditions of psychopathology, and also as pre-clinical models to evaluate candidate drugs. With hormonal treatment it is possible to produce behavior in the rat which corresponds to the mental symptoms of pre-menstrual syndrome (PMS), and pre-menstrual dysphoric disorder (PMDD). PMS affects 25-30 % of all women in fertile age and 3-8% are diagnosed with the more severe condition PMDD. The cardinal mental symptoms are; irritability, mood-swings, depression, anxiety, fatigue, insomnia, difficulties with concentration and memory and learning difficulties. The symptoms of PMS/PMDD occur in the luteal phase in conjunction with increasing concentrations of progesterone (P4) and P4-metabolites. In anovulatory cycles the symptoms are absent. The hormones which produce the monthly reoccurring negative symptoms on mood are foremost the neuroactive metabolites; allopregnanolone (ALLO) and tetrahydro-deoxycorticosterone (THDOC). ALLO is produced by the corpus luteum, but can also be synthesized in the brain, both ALLO and THDOC can also be released from the adrenal cortex during stress. These steroids are active on the inhibitory GABA neurotransmitter system through the GABAA receptor, and the effects are similar to that of alcohol and benzodiazepines. These steroids have strong sedative and hypnotic effects. A paradox is that some individuals seem to react with negative mood on sex steroids while all fertile women have the cyclical steroid changes during the menstrual cycle. Some individuals are more sensitive to neuroactive steroids with influences of personality, heritability and stress factors. Aims The thesis aims were to develop pre-clinical animal models of PMS/PMDD and to investigate induction of ALLO tolerance, individual sensitivity to neurosteroids and the interactions between chronic social stress and neurosteroids. Methods In these studies male and female Wistar rats were used to test steroid hormone effects on learning and memory and behaviors analogous to negative mood symptoms. This was accomplished through hormonal treatment and a subsequent withdrawal period from P4 (P4) + estradiol (E2) (PEWD), or ALLO. To assess tolerance, memory and learning in the Morris water maze (MWM) was studied. Anxiety-like behaviors were tested with the elevated plus maze (EPM), open field test (OFT), and the intruder test (IT). The EPM or OFT was used to classify the rats as high or low responders on risk-taking and explorative behavior (HR/LR). For social ranking order assessment the tube test (TT) and food competition test (FCT) were used. Chronic social stress was accomplished through co-habituation with two older rats (chronic subordination stress). In female rats the estrous cycle followed using staining of vaginal smears. Concentration of corticosterone (CORT) was measured by radio-immuno-assay (RIA). Results In the MWM ALLO pre-treatment produced tolerance to the acute negative ALLO effects. Both male and female rats showed behavioral correlations between the EPM and OFT tests, and correlations were also seen in CORT levels. Individuals with the stable trait of high risk-taking and explorative behavior (HR) were more sensitive to PEWD induction of anxiety-like behavior. These animals also showed decreased CORT levels during withdrawal. Chronic subordination stress enhanced the response to PEWD on measures of locomotor activity and social anxiety-like behavior. Conclusions It is possible to induce tolerance to the negative ALLO effects on learning and memory. The animal models of anxiety-like behavior show an individual PEWD response profile where HR rats are more sensitive. Exposure to chronic social stress enhanced the PEWD response. Hence there are both inherent and environmental factors behind the behavioral response to steroid hormones in rats.
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| 5. |
- Nowak, Christoph, 1986-
(författare)
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Insulin Resistance : Causes, biomarkers and consequences
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The worldwide increasing number of persons affected by largely preventable diseases like diabetes demands better prevention and treatment. Insulin is required for effective utilisation of circulating nutrients. Impaired responsiveness to insulin (insulin resistance, IR) is a hallmark of type 2 diabetes and independently raises the risk of heart attack and stroke. The pathophysiology of IR is incompletely understood. High-throughput measurement of large numbers of circulating biomarkers may provide new insights beyond established risk factors.The aims of this thesis were to (i) use proteomics, metabolomics and genomics methods in large community samples to identify biomarkers of IR; (ii) assess biomarkers for risk prediction and insights into aetiology and consequences of IR; and (iii) use Mendelian randomisation analysis to assess causality.In Study I, analysis of 80 circulating proteins in 70-to-77-year-old Swedes identified cathepsin D as a biomarker for IR and highlighted a tentative causal effect of IR on raised plasma tissue plasminogen activator levels. In Study II, nontargeted fasting plasma metabolomics was used to discover 52 metabolites associated with glycaemic traits in non-diabetic 70-year-old men. Replication in independent samples of several thousand persons provided evidence for a causal effect of IR on reduced plasma oleic acid and palmitoleic acid levels. In Study III, nontargeted metabolomics in plasma samples obtained at three time points during an oral glucose challenge in 70-year-old men identified associations between a physiologic measure of IR and concentration changes in medium-chain acylcarnitines, monounsaturated fatty acids, bile acids and lysophosphatidylethanolamines. Study IV provided evidence in two large longitudinal cohorts for causal effects of type 2 diabetes and impaired insulin secretion on raised coronary artery disease risk.In conclusion, the Studies in this thesis provide new insights into the pathophysiology and adverse health consequences of IR and illustrate the value of combining traditional epidemiologic designs with recent molecular techniques and bioinformatics methods. The results provide limited evidence for the role of circulating proteins and small molecules in IR and require replication in separate studies and validation in experimental designs.
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| 6. |
- Åkerman, Linda, 1983-
(författare)
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Aspects of the Pre-Diabetic Period in Type 1 Diabetes
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Type 1 diabetes (T1D) is an autoimmune disease characterized by insulin deficiency, due to immune-mediated destruction of beta cells. Current knowledge regarding the period preceding disease onset comes, to a large extent, from studying risk cohorts based on relatives of T1D-patients, as they have an increased disease risk. Among T1D patients in general, however, few have the disease in their immediate family. It is therefore important to study risk cohorts from the general population as well. An ongoing autoimmune reaction can often be seen in the blood long before disease onset, by detection of autoantibodies directed towards beta cell antigens. By autoantibody screening among participants in the ABIS (All Babies in the South-east of Sweden) cohort, we could identify a group of children from the general population with increased risk for T1D, positive for multiple autoantibodies. They were enrolled in a 2-year prospective follow-up aiming to characterize the prediabetic period and to identify factors indicative of progression/non-progression to T1D. We assessed glucose homeostasis and autoantibody titers over time, and searched for risk-biomarkers by analyzing the expression of immune-related genes (Th1-Th2-Th3) in peripheral blood mononuclear cells (PBMC) from these children, in comparison to healthy children and newly diagnosed T1D patients. In the same groups we also compared serum micro RNA (miRNA) profiles, knowing that miRNA molecules have desirable biomarker properties. We found that two specific autoantibodies, IA2A and ZnT8A, were detected at higher concentrations in risk-individuals who progressed to overt T1D during or after the follow-up period, compared to those who still have not. We also observed disturbed glucose homeostasis long before onset in the progressors, but it was seen among those who remain symptom free as well. Further, we found support for the possible role of insulin resistance as an accelerator of the disease process. For gene expression and serum miRNA, few differences were observed between risk-individuals and healthy children overall. However, for PBMC gene expression and serum miRNA both, there were associations to beta cell function and glucose homeostasis, and for miRNA also to islet autoantibodies. Although specific profiles for prediction of disease onset or identification of risk-individuals could not be found, these results are interesting and deserve to be evaluated further. As part of another sub-study within ABIS, the effects of physical activity on glucose homeostasis were assessed in healthy schoolchildren. The level of physical activity, measured by pedometers, was related to insulin resistance and beta cell-stress, and decreased physical activity was associated with increased insulin resistance and load on the insulin-producing beta cells, already at school-age.
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| 7. |
- Bjermo, Helena, 1981-
(författare)
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Dietary Fatty Acids and Inflammation : Observational and Interventional Studies
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Dietary fat quality influences the risk of type 2 diabetes and cardiovascular disease. A low-grade inflammation is suggested to contribute to the disease development, often accompanied by obesity. Whereas n-3 polyunsaturated fatty acids (PUFA) have been considered anti-inflammatory, n-6 PUFA have been proposed to act pro-inflammatory. Saturated fatty acids (SFA) act pro-inflammatory in vitro. This thesis aimed to investigate effects of different fatty acids on low-grade inflammation in observational and interventional studies. In Paper I and II, fatty acid composition in serum cholesterol esters was used as objective marker of dietary fat quality and related to serum C-reactive protein (CRP) and other circulating inflammatory markers in two population-based cohorts, conducted in middle-aged men and elderly men and women, respectively. In Paper III and IV, the impact of diets differing in fat quality on inflammation and oxidative stress was investigated in randomised controlled studies, in subjects with metabolic syndrome and abdominal obesity. In Paper I and II, a low proportion of linoleic acid (18:2 n-6) in serum was associated with higher CRP concentrations, indicating that a low intake of vegetable fats may be related to low-grade inflammation. High CRP concentrations were also associated with high proportions of palmitoleic (16:1) and oleic (18:1) acids and high stearoyl coenzymeA desaturase index, possibly reflecting altered fat metabolism and/or high SFA intake in this population. When comparing two high-fat diets rich in either saturated or monounsaturated fat, and two low-fat diets with or without long-chain n-3 PUFA supplementation during 12 weeks (Paper III), no differences in inflammation or oxidative stress markers were observed. Moreover, a 10-week intervention (Paper IV) with high linoleic acid intake showed no adverse effects on inflammation or oxidative stress. Instead, interleukin-1 receptor antagonist and tumor necrosis factor receptor-2 decreased after linoleic acid intake compared with a diet high in SFA. The results in this thesis indicate that dietary n-6 PUFA found in vegetable fats is associated with lower inflammation marker levels, and to some extent reduces systemic inflammation when compared with SFA. Supplementation of n-3 PUFA did not exert any systemic anti-inflammatory effects, maybe due to a relatively low dose.
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| 8. |
- Löfgren, Magnus, 1979-, et al.
(författare)
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Chronic subordination stress augments combined progesterone and estradiol withdrawal behavior
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Exposure to stress is a risk factor for developing pre-menstrual syndrome (PMS) and pre-menstrual dysphoric disorder (PMDD), and stress enhances the anxiogenic effect of female sex steroids in animals. This study examines the interaction between chronic subordination stress and withdrawal from progesterone (P4) and estradiol (E2) (PEWD) in producing behaviors analogous to anxiety and irritability in rats. At the start of the experiment, male Wistar rats were housed in triads consisting of one younger rat (~35 days) and two older rats (~50 days). The housing condition was aimed at producing chronic subordination stress in the younger animals. Chronic subordination stress was assessed by the elevated plus maze (EPM) and by corticosterone (CORT) analysis. A triad of three 35-day-old rats was used as age control. Social rank within the triads was determined using a food competition test (FCT) and the tube test (TT). The younger rats (subordinate) and the dominant rats were assigned to 10 days of treatment with 5 mg/kg progesterone combined with 10 µg/kg 17β estradiol. Twenty-four hours after the last injection, the subordinate and dominant animals were tested in the open-field test (OFT) and in the intruder test (IT). The IT consists of a 10-minute exposure to 3 unfamiliar rats. Chronic subordination stress reduced EPM open-arm time and altered the CORT response. It also made the subordinate animals more vulnerable to PEWD. The effects were increased locomotion in the OFT, increased defensive burying, and increased social anxiety in the intruder test (IT). Dominant animals did not react to PEWD. Thus, chronic subordination stress augments PEWD.
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| 9. |
- Magnusson, Louise, 1992-
(författare)
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Peripheral immunity in patients with autoimmune endocrine diseases and the influence of physiological adaptions during pregnancy
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Type 1 diabetes (T1D), Hashimoto’s thyroiditis (HT), Graves’ disease (GD), and autoimmune Addison’s disease (AD) appear to share immunogenetic mechanisms. This idea is not novel, as “autoimmune tautology” is an established concept. An issue with previous studies is that no or few simultaneous comparisons between these autoimmune endocrine diseases have been made. Due to methodological limitations, immune deviations associated with these diseases have also been examined for a limited number of immune cell lineages and analytes. High-dimensional single-cell mass cytometry was thus employed to phenotypically characterise all peripheral CD45+ cell lineages, whilst immune-related proteins in plasma and cell supernatants were analysed by proximity extension assay. Patients with new-onset T1D, HT, and AD had altered frequencies of distinct clusters within antigen-presenting and cytotoxic cell lineages. Importantly, previously unreported alterations of rare cell subsets from patients with HT and AD were identified. The systemic immunoprofile of patients with autoimmune endocrine diseases was in general similar. However, an increased abundance of CDCP1 and SLAMF1 in plasma from patients with T1D, HT, and GD might reflect a higher degree of inflammation and lymphocyte activation.Pregnancy in healthy women entails two important features: 1) an increase in fractional β-cell area and 2) peripheral immunomodulation. The effects of pregnancy on T1D remain nevertheless equivocal, as there are conflicting results on β-cell function and longitudinal analyses on peripheral immunity are lacking. β-cell function and the plasma proteome in pregnant women with long-standing T1D (L-T1D) were therefore examined during three occasions: 1) first trimester, 2) third trimester, and 3) two months postpartum. An oral glucose tolerance test was performed to measure both fasting and stimulated C-peptide concentrations in plasma. Plasma proteins related to cell regulatory and immunological processes were analysed by proximity extension assay. Glucose-induced insulin secretion was regained in pregnant women with L-T1D, which decreased slowly after parturition. The plasma proteome was dynamic during gestation, although few analytes were functionally linked. A recovered β-cell function might be related to elevated plasma levels of prolactin, prokineticin-1, or glucagon. Moreover, reduced plasma levels of proteins related to leukocyte migration, T cell activation, and antigen-presentation might have further protected an improved β-cell function.
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| 10. |
- Decker, Ralph, 1968, et al.
(författare)
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Case report of a girl with secondary amenorrhea associated with aurantiasis cutis
- 2016
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Ingår i: Hormone Research in Paediatrics. - : S. Karger AG. - 1663-2818 .- 1663-2826.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Introduction: --- Aurantiasis cutis is a condition of yellowish or golden skin discoloration that can result from eating excessive amounts of foods containing carotene leading to hypercarotenemia(1), described causing secondary amenorrhea(2). Objective & hypothesis: --- Hypercarotenemia can cause secondary amenorrhea without overconsumption of excessive quantities of carotene. Results: --- Laboratory tests showed a ß-Carotene level more than the 2-fold above the upper reference level. Hyperbilirubinemia could be excluded. Hypogonadotropic hypogonadism was not present. There was no evidence for adrenal dysfunction. Liver function tests were normal. Material/ Methods: --- A 16-year-old girl presented to our endocrine outpatient clinic with a 2-year history of varying yellow discoloration of her skin and secondary amenorrhea. The findings of the general physical examination were normal, but there was a marked yellow discoloration of the palms, soles, and nasolabial folds. A dietary history revealed a low carotene diet, but also a low carbohydrate diet. BMI was 19.9 kg/m² (-0.2 SDS) without signs of anorexia. Discussion: --- In this girl we observed hypercarotenemia associated with secondary nonhypothalamic amenorrhea in absence of excess external intake of carotenes. This suggests an intrinsic reason due to a polymorphism(3) in ß-carotene 15,15'-monooxygenase (BCO)(4), an enzyme breaking down carotenes to vitamin A(5). Phenotype-genotype association studies are needed to confirm this hypothesis. Conclusion: --- Secondary non-hypothalamic amenorrhea can be associated with hypercarotenemia. References: --- 1. Tanikawa K, Seta K, Machii A, Itoh S 1961 [Aurantiasis cutis due to overeating of dried laver (nori): a case report]. Jpn J Med Sci Biol 50:414-419 2. Kemmann E, Pasquale SA, Skaf R 1983 Amenorrhea associated with carotenemia. JAMA 249:926-929 3. Leung WC, Hessel S, Meplan C, Flint J, Oberhauser V, Tourniaire F, Hesketh JE, von Lintig J, Lietz G 2009 Two common single nucleotide polymorphisms in the gene encoding beta-carotene 15,15'-monoxygenase alter beta-carotene metabolism in female volunteers. FASEB j 23:1041-1053 4. Frumar AM, Meldrum DR, Judd HL 1979 Hypercarotenemia in hypothalamic amenorrhea. Fertil Steril 32:261-264 5. Lindqvist A, Andersson S 2002 Biochemical properties of purified recombinant human beta-carotene 15,15'-monooxygenase. J Biol Chem 277:23942-23948
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