SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Naessén Tord) ;mspu:(doctoralthesis)"

Sökning: WFRF:(Naessén Tord) > Doktorsavhandling

  • Resultat 1-6 av 6
Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  • Akhter, Tansim, 1967- (författare)
  • Carotid Artery Wall Layer Dimensions during and after Pre-eclampsia : An investigation using non-invasive high-frequency ultrasound
  • 2013
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Pre-eclampsia is associated with increased risk of cardiovascular disease (CVD) later in life. The ‘gold standard’ for estimating cardiovascular risk - ultrasound assessment of the common carotid artery intima-media thickness (CCA-IMT) - does not convincingly demonstrate this increased risk. The aim of this thesis was to examine whether high-frequency (22 MHz) ultrasound assessment of the individual CCA intima and media layers and calculation of the intima/media (I/M) ratio - can indicate the increased cardiovascular risk after pre-eclampsia. After validation of the method in premenopausal women with systemic lupus erythematosus (SLE) who have a recognized increased risk of CVD, women during and after normal and preeclamptic pregnancies were investigated.Assessment of the individual artery wall layers reliably demonstrated the increased cardiovascular risk in premenopausal women with SLE, while CCA-IMT did not. The artery wall layer dimensions in women with SLE were comparable to those of postmenopausal women without SLE and were 30 years older.Among the women with normal pregnancies negative changes to the artery wall later on in the pregnancy were seen in those with lower serum estradiol, older age, higher body mass index or higher blood pressure early in the pregnancy. About one year postpartum, both the mean intima thickness and the I/M ratio had improved, compared to values during pregnancy. These findings support the theory that normal pregnancy is a stress on the vascular system.Women who developed pre-eclampsia (mean age 31 years) had thicker intima layers, thinner media layers and higher I/M ratios, both at diagnosis and one year postpartum, than women with normal pregnancies, indicating increased cardiovascular risk.Women with a history of severe pre-eclampsia (mean age 44 years; mean 11 years since the last delivery) had thicker intima layers and higher I/M ratios than women with a history of normal pregnancies, indicating long-standing negative vascular effects.Assessment of individual CCA wall layers, but not of CCA-IMT, provided clear evidence of the well-known increased cardiovascular risk in women with SLE or pre-eclampsia. The method has the potential to become an important tool in reducing cardiovascular morbidity and mortality in these women through early diagnosis and intervention.
  •  
2.
  • Eriksson, Olle, 1954- (författare)
  • Studies on Premenstrual Dysphoria
  • 2005
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Premenstrual dysphoria, so severe that it affects the lives of the women afflicted, is the condition studied in this thesis. Physiological and pharmacological mechanisms of pathogenetic relevance were investigated. Women with premenstrual dysphoria showed a stronger and less dampened response of LH to an estradiol challenge than asymptomatic women, indicating an altered neuroendocrine regulation. In women with premenstrual dysphoria, the LH response was correlated to the severity of irritability and bloating, and the early FSH response was correlated to the severity of depressed mood. The positron-emission study showed strong, consistent correlations between worsening of mood symptoms and a decrease in brain trapping of the immediate serotonin precursor, from the mid-follicular to the late luteal phase in women with premenstrual dysphoria. The strongest correlations were seen for the cardinal mood symptoms of premenstrual dysphoria, and for their opposites. Physical symptoms showed weaker or no correlations with the exception of nociceptive symptoms from erogenous body regions which showed positive correlations to serotonin precursor trapping in the right caudate nucleus. The findings are consistent with the serotonin hypothesis of premenstrual dysphoria, and might possibly explain the observed effects of serotonin-augmenting drugs in this condition.The partial 5-HT1A receptor agonist buspirone was superior to placebo in the treatment of premenstrual dysphoria. The weak SRI and 5-HT2 receptor antagonist nefazodone was not superior to placebo. For women with premenstrual dysphoria in need of medication and who do not tolerate SRIs because of the sexual sideeffects, buspirone may be an alternative drug, since it had no adverse effects on sexual function. The prevalence of polycystic ovaries and serum levels of androgens were not higher in women with premenstrual dysphoria than in their asymptomatic counterparts. The findings are not consistent with the hypothesis that irritability in women with premenstrual dysphoria is induced by elevated testosterone levels. Thesis results, which are in line with the serotonin hypothesis of premenstrual dysphoria, may imply that increased brain sensitivity is one of the factors underlying severe premenstrual mood symptoms, thereby further supporting a common serotonergic dysregulation in this condition.
  •  
3.
  • Hallberg, Gunilla (författare)
  • Effects of Endogenous and Exogenous Hormones on the Female Breast : With Special Reference to the Expression of Proteoglycans
  • 2011
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • This thesis aims to study the effects of endogenous and exogenous hormones and mammographic breast density (BD) on cellular markers in non-cancerous female breast tissue. Women on the waiting list for breast reduction plastic surgery were recruited (n = 79), and randomized to 2 months of hormone therapy or no therapy before surgery. The women had a mammogram and a needle biopsy 2 months before surgery and tissue samples were obtained at the operation. In premenopausal women, estrogen receptor (ER)α levels were associated with age (p = 0.0002), were similar in the follicular and luteal phases of the menstrual cycle and were higher in parous than in nulliparous women (p = 0.009). Current smokers had lower PR levels than non-smokers (p = 0.019). Women on oral contraception had lower ERα (p = 0.048) and PR (p = 0.007) levels than women in the follicular phase. The ERα levels did not differ significantly between postmenopausal estrogen and estrogen-progestogen users, but PR levels were lower among estrogen-progestogen users (p = 0.03). We found lower expression of the genes for decorin and syndecans 1 and 4 in the luteal phase than in the follicular phase, among parous women. Protein levels of the androgen receptor, syndecan-4 and decorin was lower in premenopausal women who were using oral contraceptives (OC) than in those in the follicular phase (p = 0.002 - 0.02), whereas no significant differences between OC use and the luteal phase were found. In premenopausal women, BD was negatively associated with age and body mass index but was similar for the menstrual phases. Breast density was associated with genetic expression of the androgen receptor and remained significant after adjustment for age (rs = 0.56; p = 0.04). After adjustement for age, breast density was also marginally associated with expression of the caspase 3 gene (0.55; 0.053). However, protein levels of caspase 3 was negatively associated (-0.61; 0.03).
  •  
4.
  •  
5.
  • Rodriguez-Macias Wallberg, Kenny A., 1963- (författare)
  • Artery Wall Imaging and Effects of Postmenopausal Estrogen Therapy
  • 2005
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Postmenopausal estrogen therapy, initiated early in the menopause, seems to protect against development of atherosclerosis and cardiovascular diseases. This thesis concerns studies of artery wall thickness and arterial stiffness estimated by noninvasive ultrasound techniques in long-term estrogen treated postmenopausal women who initiated therapy at the time of the menopause.A noninvasive 25 MHz high-frequency ultrasound technique was validated in the imaging of superficial arteries by using an animal model. Ultrasound estimates of the artery wall layers obtained in vivo in the pig were compared to ex-vivo histomorphometry. Valid estimates of total artery wall and media thickness were found for the most superficial arteries. Adventitia thickness was underestimated and intima thickness overestimated in this animal model when non-atherosclerotic vessels were imaged.To validate the clinical usefulness of separately estimating the artery wall layers in the human, the carotid artery wall was imaged in elderly subjects. Separate estimates of intima thickness, media thickness and intima/media ratio differed significantly between subjects with and without atherosclerosis and CVD, indicating that this noninvasive high-frequency ultrasound method might be a strong tool in monitoring changes in artery wall morphology associated with aging and development of atherosclerosis.The investigation of intima thickness, media thickness and intima/media ratio of the carotid and femoral arteries in long-term estrogen treated postmenopausal women showed a maintenance of a thin intima and a preservation of media thickness and intima/media ratio at values similar to those obtained in women of fertile age. By comparing estrogen-users with age-matched postmenopausal nonusers, long-term estrogen therapy initiated at the time of the menopause seemed to counteract the increase in intima and decrease in media thickness associated with aging and development of atherosclerosis. The preservation of the artery wall morphology into older age might be a mechanism for the well-documented cardioprotective effects of estrogen when therapy is initiated early after menopause. However, long-term estrogen therapy showed no substantial effects on the age-related changes in arterial stiffness estimated at the aorta, carotid and femoral arteries, suggesting that any long-term cardioprotective effect that estrogen therapy may have is unlikely to be mediated by an impact on arterial stiffness.
  •  
6.
  • Wihlbäck, Anna-Carin, 1962- (författare)
  • Ovarian hormones and effects in the brain : studies of neurosteroid sensitivity, serotonin transporter and serotonin2A receptor binding in reproductive and postmenopausal women
  • 2004
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Background: Estrogen has been reported to enhance well-being and quality of life during the climacteric phase. In women with an intact uterus estrogen treatment is always combined with progestins in order to protect the endometrium from hyperplasia and malignancies. However, in certain women the addition of progestins causes cyclicity in negative mood symptoms and physical symptoms similar to those encountered during ovulatory cycles in women with premenstrual dysphoric disorder (PMDD). The ovarian hormones estradiol and progesterone have profound effects on a number of neurotransmitter systems in the brain, such as the gamma aminobutyric acid (GABA) system and the serotonergic system. Progesterone metabolites, such as allopregnanolone and pregnanolone (also referred to as neurosteroids) modify the GABAA receptor in the central nervous system (CNS) and enhance GABAergic inhibitory transmission. Neurosteroid sensitivity in human studies can be studied by saccadic eye movement measurements using pharmacodynamic challenges with pregnanolone. Altered neurosteroid sensitivity has been suggested as a possible contributory factor to the progesterone/progestin-induced adverse mood effects of hormone replacement therapy (HRT). There is also evidence of estrogen treatment affecting the serotonergic system in postmenopausal women, although progestin addition has been less well studied. Aims and method: The aim was to investigate whether the negative mood symptoms experienced during the progestin or progesterone phase of HRT were associated with changes in neurosteroid sensitivity, or changes in platelet serotonin uptake site (transporter) and serotonin2A (5-HT2A) receptor binding. The intention was also to investigate whether hormonal changes during the normal menstrual cycle affect these peripheral serotonergic parameters. Postmenopausal women with climacteric symptoms were given HRT in two randomized, double-blinded, placebo-controlled crossover studies. The women received 2 mg estradiol (E2) continuously during 28- day cycles. Synthetic progestins or natural progesterone were added sequentially during the last 14 days, and compared to a placebo addition. Before treatment, as well as during the last week of each treatment cycle the pharmacodynamic response to pregnanolone was assessed using saccadic eye movement measurements. Throughout the studies daily symptom ratings were made. In the study regarding synthetic progestins, platelet serotonin transporter and 5-HT2A receptor binding were assayed before entering the study, as well as during the last week of each treatment cycle. In the study on reproductive women, blood samples were collected for analysis of platelet serotonin transporter and 5-HT2A receptor binding at six different points in time during the menstrual cycle. Results and conclusion: The addition of synthetic progestins to estrogen treatment increased negative mood symptoms and physical symptoms, whereas positive symptoms decreased. The addition of progestins also increased the sensitivity to pregnanolone. The addition of natural progesterone to estrogen treatment increased the sensitivity to pregnanolone. However, in this study the pregnanolone sensitivity was enhanced also during estrogen treatment. Women expressing cyclicity in negative mood symptoms were more sensitive to pregnanolone than women without symptom cyclicity. Thus, it is evident that mood deterioration during HRT is associated with altered neurosteroid sensitivity. Platelet serotonin transporter and 5-HT2A receptor binding did not change during the different treatment conditions in HRT. Thus, we were unable to explain the negative mood changes of HRT by use of these peripheral serotonergic parameters. In the study on reproductive women however, it was clear that the serotonergic variables did change during the menstrual cycle. Binding to the serotonin transporter was higher in the late follicular phase than in the ovulatory, early luteal or mid-luteal phases. Binding to the 5-HT2A receptor was higher in the early follicular phase and the early luteal phase than in the mid-luteal phase. These findings may provide a link between the ovarian steroids, and the GABAergic and serotonergic neurotransmitter systems, which in turn, could explain part of the specific vulnerability that women have for the development of adverse mood effects during HRT, mood and anxiety disorders and for the deterioration of mood so frequently seen during the luteal phase.
  •  
Skapa referenser, mejla, bekava och länka
  • Resultat 1-6 av 6

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy