924 resultados para Salivary testosterone
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There is increasing evidence to support a significant role for chronic non-bacterial, prostatic inflammation in the development of human voiding dysfunction and prostate cancer. Their increased prevalence with age suggests that the decrease of testosterone concentration and/or the ratio of testosterone-to-estradiol in serum may have a role in their development. The main objective of this study was to explore prostatic inflammation and its relationship with voiding dysfunction and prostate carcinogenesis by developing an experimental model. A novel selective estrogen receptor modulator (SERM), fispemifene, was tested for the prevention and treatment of prostatic inflammation in this model. Combined treatment of adult Noble rats with testosterone and estradiol for 3 to 6 weeks induced gradually developing prostatic inflammation in the dorsolateral prostatic lobes. Inflammatory cells, mainly T-lymphocytes, were first seen around capillaries. Thereafter, the lymphocytes migrated into the stroma and into periglandular space. When the treatment time was extended to 13 weeks, the number of inflamed acini increased. Urodynamical recordings indicated voiding dysfunction. When the animals had an above normal testosterone and estradiol concentrations but still had a decreased testosterone-to-estradiol ratio in serum, they developed obstructive voiding. Furthermore, they developed precancerous lesions and prostate cancers in the ducts of the dorsolateral prostatic lobes. Interestingly, inflammatory infiltrates were observed adjacent to precancerous lesions but not in the adjacency of adenocarcinomas suggesting that inflammation has a role in the early stages of prostate carcinogenesis. Fispemifene, a novel SERM tested in this experimental model, showed anti-inflammatory action by attenuating the number of inflamed acini in the dorsolateral prostate. Fispemifene exhibited also antiestrogenic properties by decreasing expression of estrogen-induced biomarkers in the acinar epithelium. These findings suggest that SERMs could be considered as a new therapeutic possibility in the prevention and in the treatment of chronic prostatic inflammation
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Human chorionic gonadotropin (hCG) and luteinizing hormone (LH) are structurally and functionally similar glycoprotein hormones acting through the same luteinizing hormone chorionic gonadotropin receptor (LHCGR). The functions of LH in reproduction and hCG in pregnancy are well known. Recently, the expression of LHCGR has been found in many nongonadal tissues and cancers, and this has raised the question of whether LH/hCG could affect the function or tumorigenesis of these nongonadal tissues. We have also previously generated an hCG expressing mouse model presenting nongonadal phenotypes. Using this model it is possible to improve our understanding of nongonadal action of highly elevated LH/hCG. In the current study, we analyzed the effect of moderately and highly elevated hCG levels on male reproductive development and function. The main finding was the appearance of fetal Leydig cell (FLC) adenomas in prepubertal males. However, the development and differentiation of FLCs were not significantly affected. We also show that the function of hCG is different in FLCs and in adult Leydig cells (ALC), because in the latter cells hCG was not able to induce tumorigenesis. In FLCs, LHCGR is not desensitized or downregulated upon ligand binding. In this study, we found that the testicular expression of two G protein-coupled receptor kinases responsible for receptor desensitization or downregulation is increased in adult testis. Results suggest that the lack of LHCGR desensitization or downregulation in FLCs protect testosterone (Te) synthesis, but also predispose FLCs for LH/hCG induced adenomas. However, all the hCG induced nongonadal changes observed in male mice were possible to explain by the elevated Te level found in these males. Our findings indicate that the direct nongonadal effects of elevated LH/hCG in males are not pathophysiologically significant. In female mice, we showed that an elevated hCG level was able to induce gonadal tumorigenesis. hCG also induced the formation of pituitary adenomas (PA), but the mechanism was indirect. Furthermore, we found two new potential risk factors and a novel hormonally induced mechanism for PAs. Increased progesterone (P) levels in the presence of physiological estradiol (E2) levels induced the formation of PAs in female mice. E2 and P induced the expression and nuclear localization of a known cell-cycle regulator, cyclin D1. A calorie restricted diet was also able to prevent the formation of PAs, suggesting that obesity is able to promote the formation of PAs. Hormone replacement therapy after gonadectomy and hormone antagonist therapy showed that the nongonadal phenotypes observed in hCG expressing female mice were due to ovarian hyperstimulation. A slight adrenal phenotype was evident even after gonadectomy in hCG expressing females, but E2 and P replacement was able to induce a similar phenotype in WT females without elevated LH/hCG action. In conclusion, we showed that the direct effects of elevated hCG/LH action are limited only to the gonads of both sexes. The nongonadal phenotypes observed in hCG expressing mice were due to the indirect, gonadal hormone mediated effects of elevated hCG. Therefore, the gonads are the only physiologically significant direct targets of LHCGR signalling.
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Hormone-dependent diseases, e.g. cancers, rank high in mortality in the modern world, and thus, there is an urgent need for new drugs to treat these diseases. Although the diseases are clearly hormone-dependent, changes in circulating hormone concentrations do not explain all the pathological processes observed in the diseased tissues. A more inclusive explanation is provided by intracrinology – a regulation of hormone concentrations at the target tissue level. This is mediated by the expression of a pattern of steroid-activating and -inactivating enzymes in steroid target tissues, thus enabling a concentration gradient between the blood circulation and the tissue. Hydroxysteroid (17beta) dehydrogenases (HSD17Bs) form a family of enzymes that catalyze the conversion between low active 17-ketosteroids and highly active 17beta-hydroxysteroids. HSD17B1 converts low active estrogen (E1) to highly active estradiol (E2) with high catalytic efficiency, and altered HSD17B1 expression has been associated with several hormone-dependent diseases, including breast cancer, endometriosis, endometrial hyperplasia and cancer, and ovarian epithelial cancer. Because of its putative role in E2 biosynthesis in ovaries and peripheral target tissues, HSD17B1 is considered to be a promising drug target for estrogen-dependent diseases. A few studies have indicated that the enzyme also has androgenic activity, but they have been ignored. In the present study, transgenic mice overexpressing human HSD17B1 (HSD17B1TG mice) were used to study the effects of the enzyme in vivo. Firstly, the substrate specificity of human HSD17B1 was determined in vivo. The results indicated that human HSD17B1 has significant androgenic activity in female mice in vivo, which resulted in increased fetal testosterone concentration and female disorder of sexual development appearing as masculinized phenotype (increased anogenital distance, lack of nipples, lack of vaginal opening, combination of vagina with urethra, enlarged Wolffian duct remnants in the mesovarium and enlarged female prostate). Fetal androgen exposure has been linked to polycystic ovary syndrome (PCOS) and metabolic syndrome during adulthood in experimental animals and humans, but the genes involved in PCOS are largely unknown. A putative mechanism to accumulate androgens during fetal life by HSD17B1 overexpression was shown in the present study. Furthermore, as a result of prenatal androgen exposure locally in the ovaries, HSD17B1TG females developed ovarian benign serous cystadenomas in adulthood. These benign lesions are precursors of low-grade ovarian serous tumors. Ovarian cancer ranks fifth in mortality of all female cancers in Finland, and most of the ovarian cancers arise from the surface epithelium. The formation of the lesions was prevented by prenatal antiandrogen treatment and by transplanting wild type (WT) ovaries prepubertally into HSD17B1TG females. The results obtained in our non-clinical TG mouse model, together with a literature analysis, suggest that HSD17B1 has a role in ovarian epithelial carcinogenesis, and especially in the development of serous tumors. The role of androgens in ovarian carcinogenesis is considered controversial, but the present study provides further evidence for the androgen hypothesis. Moreover, it directly links HSD17B1-induced prenatal androgen exposure to ovarian epithelial carcinogenesis in mice. As expected, significant estrogenic activity was also detected for human HSD17B1. HSD17B1TG mice had enhanced peripheral conversion of E1 to E2 in a variety of target tissues, including the uterus. Furthermore, this activity was significantly decreased by treatments with specific HSD17B1 inhibitors. As a result, several estrogen-dependent disorders were found in HSD17B1TG females. Here we report that HSD17B1TG mice invariably developed endometrial hyperplasia and failed to ovulate in adulthood. As in humans, endometrial hyperplasia in HSD17B1TG females was reversible upon ovulation induction, triggering a rise in circulating progesterone levels, and in response to exogenous progestins. Remarkably, treatment with a HSD17B1 inhibitor failed to restore ovulation, yet completely reversed the hyperplastic morphology of epithelial cells in the glandular compartment. We also demonstrate that HSD17B1 is expressed in normal human endometrium, hyperplasia, and cancer. Collectively, our non-clinical data and literature analysis suggest that HSD17B1 inhibition could be one of several possible approaches to decrease endometrial estrogen production in endometrial hyperplasia and cancer. HSD17B1 expression has been found in bones of humans and rats. The non-clinical data in the present study suggest that human HSD17B1 is likely to have an important role in the regulation of bone formation, strength and length during reproductive years in female mice. Bone density in HSD17B1TG females was highly increased in femurs, but in lesser amounts also in tibias. Especially the tibia growth plate, but not other regions of bone, was susceptible to respond to HSD17B1 inhibition by increasing bone length, whereas the inhibitors did not affect bone density. Therefore, HSD17B1 inhibitors could be safer than aromatase inhibitors in regard to bone in the treatment of breast cancer and endometriosis. Furthermore, diseases related to improper growth, are a promising new indication for HSD17B1 inhibitors.
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Probiotic lactobacilli and bifidobacteria in the mouth – in vitro studies on saliva-mediated functions and acid production Probiotics are viable bacteria which, when used in adequate amounts, are beneficial to the health of the host. Although most often related to intestinal health, probiotic bacteria can be found also in the mouth after consumption of products that contain them. This study aimed at evaluating the oral effects of probiotic bacteria already in commercial use. In a series of in vitro studies, the oral colonisation potential of different probiotic bacteria, their acid production and potential saliva-mediated effects on oral microbial ecology were investigated. The latter included effects on the salivary pellicle, the adhesion of other bacteria, and the activation of the peroxidase system. Streptococcus mutans, Streptococcus gordonii, Aggregatibacter actinomycetemcomitans and Helicobacter pylori were used as bacterial indicators of the studied phenomena. There were significant differences between the probiotic strains in their colonisation potential. They all were acidogenic, although using different sugars and sugar alcohols. However, their acid production could be inhibited by the peroxidase system. Based on the results, it can be suggested that probiotic bacteria might influence the oral microbiota by different, partly species or strain-specific means. These include the inhibition of bacterial adhesion, modification of the enamel pellicle, antimicrobial activity, and activation of the peroxidase system. To conclude, probiotic strains differed from each other in their colonisation potential and other oral effects as evaluated in vitro. Both positive and potentially harmful effects were observed, but the significance of the perceived results needs to be further evaluated in vivo.
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In vitro release of bioidentical hormones in four different liposomal transdermal emulsions (containing testosterone, progesterone, estradiol, or estradiol and estriol) was assessed. For this purpose, novel high-performance liquid chromatography methods were developed and validated in an eco-friendly manner and used to determine the in vitro release of such products. The methods were suitable for our intended goal, and the emulsions employed were found to be effective as transporting candidates for the efficient release of hormones in the transdermal delivery of human sexual steroids.
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The growth of breast cancer is regulated by hormones and growth factors. Recently, aberrant fibroblast growth factor (FGF) signalling has been strongly implicated in promoting the progression of breast cancer and is thought to have a role in the development of endocrine resistant disease. FGFs mediate their auto- and paracrine signals through binding to FGF receptors 1-4 (FGFR1-4) and their isoforms. Specific targets of FGFs in breast cancer cells and the differential role of FGFRs, however, are poorly described. FGF-8 is expressed at elevated levels in breast cancer, and it has been shown to act as an angiogenic, growth promoting factor in experimental models of breast cancer. Furthermore, it plays an important role in mediating androgen effects in prostate cancer and in some breast cancer cell lines. We aimed to study testosterone (Te) and FGF-8 regulated genes in Shionogi 115 (S115) breast cancer cells, characterise FGF-8 activated intracellular signalling pathways and clarify the role of FGFR1, -2 and -3 in these cells. Thrombospondin-1 (TSP-1), an endogenous inhibitor of angiogenesis, was recognised as a Te and FGF-8 regulated gene. Te repression of TSP-1 was androgen receptor (AR)-dependent. It required de novo protein synthesis, but it was independent of FGF-8 expression. FGF-8, in turn, downregulated TSP-1 transcription by activating the ERK and PI3K pathways, and the effect could be reversed by specific kinase inhibitors. Differential FGFR1-3 action was studied by silencing each receptor by shRNA expression in S115 cells. FGFR1 expression was a prerequisite for the growth of S115 tumours, whereas FGFR2 expression alone was not able to promote tumour growth. High FGFR1 expression led to a growth advantage that was associated with strong ERK activation, increased angiogenesis and reduced apoptosis, and all of these effects could be reversed by an FGFR inhibitor. Taken together, the results of this thesis show that FGF-8 and FGFRs contribute strongly to the regulation of the growth and angiogenesis of experimental breast cancer and support the evidence for FGF-FGFR signalling as one of the major players in breast cancers.
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The aim of this thesis was to evaluate the short- and long-term effectiveness of a prefabricated occlusal appliance (R) on patients with myofascial pain and headache by comparing it with the treatment of the stabilization appliance (S). Another aim was to evaluate the effect of appliance treatment on stress-related salivary parameters like cortisol and IgA, as well as on flow rate values in these patients. Sixty-five patients diagnosed with myofascial temporomandibular disorder (TMD) pain, of whom 94% suffered concomitantly from headache, at two centres for Stomatognathic Physiology, one in Sweden and one in Finland, were included in this randomized controlled trial using Research Diagnostic Criteria for TMD (RDC/TMD), with history questionnaires and clinical examinations performed at baseline and at 6- and 10-weeks, and 6- and 12-month follow-ups. Patients were randomly assigned either to the R or the S group. Treatment outcome was measured according to IMMPACT (Initiative on Methods, Measurements, and Pain Assessment in Clinical Trials), i.e. four chronic pain outcome domains: pain intensity, overall improvement, physical and emotional functioning. Changes in frequency and intensity of headache were recorded. Thirty-nine patients participated in the saliva study. Salivary analyses were performed at 6 and 10 weeks. The results revealed no differences between groups at baseline. At all follow-ups, all four outcome measures, as well as frequency and intensity of headache, showed statistically significant within-group improvement compared to baseline, without significant differences between groups. No treatment-induced changes in saliva parameters could be registered. In conclusion, the effectiveness of the prefabricated appliance seemed to be similar to that of the stabilization appliance in alleviating myofascial pain, and frequency and intensity of headache, in the short as well as the long term. However, no changes in salivary parameters were observed during treatment.
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Astringency is traditionally thought to be induced by plant tannins in foods. Because of this current research concerning the mechanism of astringency is focused on tannin‐protein interactions and thus on precipitation, which may be perceived by mechanoreceptors. However, astringency is elicited by a wide range of different phenolic compounds, as well as, some non‐phenolic compounds in various foods. Many ellagitannins or smaller compounds that contribute to astringent properties do not interact with salivary proteins and may be directly perceived through some receptors. Generally, the higher degree of polymerization of proanthocyanidins can be associated with more intense astringency. However, the astringent properties of smaller phenolic compounds may not be directly predicted from the structure of a compound, although glycosylation has a significant role. The astringency of organic acids may be directly linked to the perception of sourness, and this increases along with decreasing pH. Astringency can be divided into different sub‐qualities, including even other qualities than traditional mouth‐drying, puckering or roughing sensations. Astringency is often accompanied by bitter or sour or both taste properties. The different sub‐qualities can be influenced by different astringent compounds. In general, the glycolysation of the phenolic compound results in more velvety and smooth mouthdrying astringency. Flavonol glycosides and other flavonoid compounds and ellagitannins contribute to this velvety mouthdrying astringency. Additionally, they often lack the bitter properties. Proanthocyanidins and phenolic acids elicit more puckering and roughing astringency with some additional bitter properties. Quercetin 3‐O‐rutinoside, along with other quercetin glycosides, is among the key astringent compounds in black tea and red currants. In foods, there are always various other additional attributes that are perceived at the same with astringency. Astringent compounds themselves may have other sensory characteristics, such as bitter or sour properties, or they may enhance or suppress other sensory properties. Components contributing to these other properties, such as sugars, may also have similar effects on astringent sensations. Food components eliciting sweetness or fattiness or some polymeric polysaccharides can be used to mask astringent subqualities. Astringency can generally be referred to as a negative contributor to the liking of various foods. On the other hand, perceptions of astringent properties can vary among individuals. Many genetic factors that influence perceptions of taste properties, such as variations in perceiving a bitter taste or variations in saliva, may also effect the perception of astringency. Individuals who are more sensitive to different sensations may notice the differences between astringent properties more clearly. This may not have effects on the overall perception of astringency. However, in many cases, the liking of astringent foods may need to be learned by repetitive exposure. Astringency is often among the key sensory properties forming the unique overall flavour of certain foods, and therefore it also influences whether or not a food is liked. In many cases, astringency may be an important sub‐property suppressed by other more abundant sensory properties, but it may still have a significant contribution to the overall flavour and thus consumer preferences. The results of the practical work of this thesis show that the astringent phenolic compounds are mostly located in the skin fractions of black currants, crowberries and bilberries (publications I–III). The skin fractions themselves are rather tasteless. However, the astringent phenolic compounds can be efficiently removed from these skin fractions by consecutive ethanol extractions. Berries contain a wide range of different flavonol glycosides, hydroxycinnamic acid derivatives and anthocyanins and some of them strongly contribute to the different astringent and bitterness properties. Sweetness and sourness are located in the juice fractions along with the majority of sugars and fruit acids. The sweet and sour properties of the juice may be used to mask the astringent and bitterness properties of the extracts. Enzymatic treatments increase the astringent properties and fermented flavour of the black currant juice and decrease sweetness and freshness due to the effects on chemical compositions (IV). Sourness and sweetness are positive contributors to the liking of crowberry and bilberry fractions, whereas bitterness is more negative (V). Some astringent properties in berries are clearly negative factors, whereas some may be more positive. The liking of berries is strongly influenced by various consumer background factors, such as motives and health concerns. The liking of berries and berry fractions may also be affected by genetic factors, such as variations in the gene hTAS2R38, which codes bitter taste receptors (V).
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OBJECTIVE: to analyze the value of fine needle aspiration and the rates of postoperative complications in patients undergoing resection of the submandibular gland. METHODS: we analyzed the records of patients treated with resection of the gland from January 1995 to December 2008. The data collected included age, gender, findings on clinical history, surgical procedure, results of fine needle aspiration (FNA), pathological diagnosis and complications. RESULTS: 117 patients were studied, aged 12-89 years (mean 48), 70 women and 47 men. Thirty-nine patients (33.3%) were affected by inflammatory diseases (28 patients with lithiasis), 70 had benign tumors, and malignant tumors, eight. Regarding FNA, the sensitivity and specificity were 85.7% and 100%, respectively. Nine patients (7.7%) had temporary paralysis of the marginal mandibular nerve and one had permanent paralysis. CONCLUSION: resection of the submandibular gland is a safe procedure, with low complication rates.
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The antiandrogenic therapy (ADT) for prostate cancer represents an additional risk factor for the development of osteoporosis and fragility fractures. Still, bone health of patients on ADT is often not evaluated. After literature research we found that simple preventive measures can prevent bone loss in these patients, resulting in more cost-effective solutions to the public health system and family when compared to the treatment of fractures.
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Objective Polycystic ovary syndrome (PCOS) is the most common endocrine metabolic disorder in women between menarche and menopause. Clinical hyperandrogenism is the most important diagnostic criterion of the syndrome, which manifests as hirsutism in 70% of cases. Hirsute carriers of PCOS have high cardiovascular risk. Lipid accumulation product (LAP) is an index for the evaluation of lipid accumulation in adults and the prediction of cardiovascular risk. The aim of this study was to evaluate the association between LAP and hirsutism in women with PCOS. Methods This was a cross-sectional observational study of a secondary database, which included 263 patients who had visited the Hyperandrogenism Outpatient Clinic from November 2009 to July 2014. The exclusion criteria were patients without Ferriman-Gallwey index (FGI) and/or LAP data. We used the Rotterdam criteria for the diagnosis of PCOS. All patients underwent medical assessment followed by measurement and recording of anthropometric data and the laboratory tests for measurement of the following: thyroid-stimulating hormone, follicle-stimulating hormone, prolactin, total testosterone, sex hormone binding globulin, 17-α-hydroxyprogesterone (follicular phase), glycohemoglobin A1c, and basal insulin. In addition, the subjects underwent lipid profiling and oral glucose tolerance tests. Other laboratory measurements were determined according to clinical criteria. LAP and the homeostatic model assessment index (HOMA-IR) were calculated using the data obtained. We divided patients into two groups: the PCOS group with normal LAP (< 34.5) and the PCOS group with altered LAP (> 34.5) to compare the occurrence of hirsutism. For statistical analysis, we used SPSS Statistics for Windows(r) and Microsoft Excel programs, with descriptive (frequencies, percentages, means, and standard deviations) and comparative analyses (Student's t-test and Chi-square test). We considered relations significant when the p-value was≤0.05. Results LAP was high in most patients (n = 177; 67.3%) and the FGI indicated that 58.5% of the patients (n = 154) had hirsutism. The analysis by LAP quartiles showed a positive correlation (p = 0.04) among patients with a high FGI and an upper quartile LAP (> 79.5) when compared with those with LAP < 29.0 (lower quartile). Conclusion This study demonstrated an association between high LAP and hirsutism. The FGI could represent a simple and low-cost tool to infer an increased cardiovascular risk in women with PCOS.
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Rabies is a neurological disease, but the rabies virus spread to several organs outside the central nervous system (CNS). The rabies virus antigen or RNA has been identified from the salivary glands, the lungs, the kidneys, the heart and the liver. This work aimed to identify the presence of the rabies virus in non-neuronal organs from naturally-infected vampire bats and to study the rabies virus in the salivary glands of healthy vampire bats. Out of the five bats that were positive for rabies in the CNS, by fluorescent antibody test (FAT), viral isolation in N2A cells and reverse transcription - polymerase chain reaction (RT-PCR), 100% (5/5) were positive for rabies in samples of the tongue and the heart, 80% (4/5) in the kidneys, 40% (2/5) in samples of the salivary glands and the lungs, and 20% (1/5) in the liver by RT-PCR test. All the nine bats that were negative for rabies in the CNS, by FAT, viral isolation and RT-PCR were negative for rabies in the salivary glands by RT-PCR test. Possible consequences for rabies epidemiology and pathogenesis are discussed in this work.
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The impact of menopausal hormone therapy (MHT) on increasing the risk for breast cancer (BC) remains controversial. To understand MHT-elicited cellular breast effects and the potential risks, included with using this therapy, a further investigation into this controversy is the subject of this thesis. In this thesis, to study the effects of estrogen, progestin, androgens and selective estrogen receptor modulators (SERMs), a modified tissue explant culture system was used. The different types of human breast tissues (HBTs) used in this study were normal HBTs, obtained from reduction mammoplasties of premenopausal women (prem-HBTs) or postmenopausal (postm-HBTs) women and peritumoral HBTs (peritum-HBTs) which were obtained from surgeries on postmenopausal BC patients. The explants were cultured up to three weeks in the presence or absence of estradiol (E2), medroxyprogesterone acetate (MPA), testosterone (T), dihydrotestosterone (DHT) and SERMs - ospemifene (OSP), raloxifene (RAL) and tamoxifen (TAM). The cultured HBTs maintained morphological integrity and responded to hormonal treatment in vitro. E2, MPA or E2/MPA increased proliferative activity and was associated with increased cyclin-D1 and caused changes in the cell cycle inhibitors p21 and p27, whereas the androgens T and DHT inhibited proliferation and increased apoptosis in HBT epithelia and opposed E2-stimulated proliferation and cell survival. The postm-HBTs were more sensitive to E2 than prem-HBTs. The effects of OSP, RAL and TAM on HBT epithelium were antiproliferative. E2, androgens and SERMs were associated with marked changes in the proportions of epithelial cells expressing steroid hormone receptors: E2 increased ERα expressing cells and decreased androgen receptor (AR) positive cells, whereas T and DHT had opposite effects. The OSP, RAL and TAM, also decreased a proportion of ERα positive cells in HBT epithelium. At 100 nM, these compounds maintained the relative number of AR positive cells, present at control level, which may partly explain proliferative inhibition. In conclusion, the proliferative activity of E2, in the epithelium of postm-HBTs, is opposed by T and DHT, which suggests that the inclusion of androgens in MHT may decrease the risk for developing BC.
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Background: In the past, oxidized low density lipoprotein (ox-LDL) has been associated with an unbeneficial lipid profile. This atherogenic lipid profile increases the risk of atherosclerotic cardiovascular diseases. Physical fitness has substantial effect on serum lipoprotein concentration as well as body composition and humoral responses, however interrelationships between ox-LDL and physical fitness have not been widely examined in a nationally representative sample. Aims: This thesis evaluates how cardiorespiratory and muscular fitness associate with ox-LDL lipids and how the other known risk factors of atherosclerosis might alter these associations. Subjects and Methods: The study cohort consisted of 846 healthy young males (mean age 25.1, SD 4.6) who were gathered by voluntary nationwide recruitment. Each participant conducted a series of physical fitness tests (cardiorespiratory and muscular fitness) and answered a detailed questionnaire that included lifestyle habits (i.e. smoking and leisuretime physical activity). Venous blood samples including ox-LDL and serum lipids were also collected. Results: Higher levels of ox-LDL were found in overweight and obese men, however, high cardiorespiratory fitness seemed to protect the overweight from high levels of ox-LDL. Young men who smoked and had poor cardiorespiratory or muscular fitness possessed a higher concentration of ox-LDL lipids when compared to comparable levels of cardiorespiratory or muscular fitness non-smoking young men. Metabolic syndrome was associated with increased levels of ox-LDL and high levels of ox-LDL combined with poor cardiorespiratory and abdominal muscle fitness seems to predict metabolic syndrome in young men. Also, participants with poor cardiorespiratory fitness and low levels of testosterone had higher levels of ox-LDL when compared to participants with high cardiorespiratory fitness / low testosterone as well as those with poor cardiorespiratory fitness / high testosterone. Conclusions: Good cardiorespiratory and muscular fitness protects young men from increased levels of ox-LDL lipids. This association was discovered in young men who were categorized as being overweight, smokers, metabolic syndrome or with low levels of testosterone. Being fit seems to prevent higher levels of ox-LDL, even in young healthy
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It has been commonly thought that standards of beauty are arbitrary cultural conventions that vary between cultures and time. In my thesis I found that it is not so. Instead, I show that attractiveness and preferred traits serve as cues to phenotypic qualities that provide selective benefits for those who choose their mates based on these criteria. In the first study I show that attractive men have a stronger antibody response to the hepatitis b vaccine and higher levels of testosterone than their less attractive peers. Men with low levels of testosterone also tend to have high levels of the stress hormone cortisol, suggesting that their immune responses may have been inhibited by stress hormones. Thus, facial attractiveness may serve as an honest cue of the strength of immune defence in men. In the second study, I show that the attractiveness of the male body is also a cue of better immunity. In addition, I show that adiposity, both in men’s faces and bodies, is a better cue of the strength of immunity and attractiveness than of masculinity. In the third study, I test the preferences of women from 13 countries for facial cues of testosterone and cortisol. I show that there is cross-cultural variation in women’s preference for cues of testosterone and cortisol in male faces. I found a relationship between the health of a nation and women’s preferences for cues of testosterone in the male face and the interaction between preferences for cues of testosterone and cortisol. I show also a relationship between preferences for cues of testosterone and a societal-level measure of parasite stress. Thus, it seems that societal-level ecological factors influence the relative value of traits as revealed by combinations of testosterone and stress hormones. In the fourth study, I show that women’s immune responsiveness (amount of antibodies produced) does not predict facial attractiveness. Instead, plasma cortisol level is negatively associated with attractiveness, indicating that stressed women look less attractive. Fat percentage is curvilinearly associated with facial attractiveness, indicating that being too thin or too fat reduces attractiveness. This study suggests that in contrast to men, facial attractiveness in women does not indicate the strength of immune defence, but is associated with other aspects of long-term health and fertility: circulating levels of the stress hormone cortisol and the percentage of body fat. In the last study I show that the attractiveness of men’s body odor is positively correlated with stress hormone levels, suggesting also that the attractiveness of body odors may signal the phenotypic quality of males to females. However, the attractiveness of men’s body odor was not associated with testosterone levels. My thesis suggests that the standard of beauty is not in the eye of the beholder. Instead, our standard of beauty is hardwired in our brains by genes that are selected by natural selection and also influenced by current environmental conditions.