380 resultados para lääketiede


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The incidence of type 2 diabetes has increased rapidly worldwide. Obesity is one of the most important modifiable risk factors of type 2 diabetes: weight gain increases and weight loss decreases the risk. However, the effects of weight fluctuation are unclear. Reactive oxygen species are presumably part of the complicated mechanism for the development of insulin resistance and beta-cell destruction in the pancreas. The association of antioxidants with the risk of incident type 2 diabetes has been studied in longitudinal prospective human studies, but so far there is no clear conclusion about protective effect of dietary or of supplementary antioxidants on diabetes risk. The present study examined 1) weight change and fluctuation as risk factors for incident type 2 diabetes; 2) the association of baseline serum alpha-tocopherol or beta-carotene concentration and dietary intake of antioxidants with the risk of type 2 diabetes; 3) the effect of supplementation with alpha-tocopherol or beta-carotene on the risk of incident type 2 diabetes; and on macrovascular complications and mortality among type 2 diabetics. This investigation was part of the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study, a randomized, double-blind, placebo-controlled prevention trial, which has undertaken to examine the effect of alpha-tocopherol and beta-carotene supplementation on the development of lung cancer, other cancers, and cardiovascular diseases in male smokers aged 50-69 years at baseline. Participants were assigned to receive either 50 mg alpha-tocopherol, 20mg beta-carotene, both, or placebo daily in a 2 x 2 factorial design experiment during 1985-1993. Cases of incident diabetes were identified through a nationwide register of drug reimbursements of the Social Insurance Institution. At baseline 1700 men had a history of diabetes. Among those (n = 27 379) with no diabetes at baseline 305 new cases of type 2 diabetes were recognized during the intervention period and 705 during the whole follow-up to 12.5 years. Weight gain and weight fluctuation measured over a three year period were independent risk factors for subsequent incident type 2 diabetes. Relative risk (RR) was 1.77 (95% confidence interval [CI] 1.44-2.17) for weight gain of at least 4 kg compared to those with a weight change of less than 4 kg. The RR in the highest weight fluctuation quintile compared to the lowest was 1.64 (95% CI 1.24-2.17). Dietary tocopherols and tocotrienols as well as dietary carotenoids, flavonols, flavones and vitamin C were not associated with the risk of type 2 diabetes. Baseline serum alpha-tocopherol and beta-carotene concentrations were not associated with the risk of incident diabetes. Neither alpha-tocopherol nor beta-carotene supplementation affected the risk of diabetes. The relative risks for participants who received alpha-tocopherol compared with nonrecipients and for participants who received beta-carotene compared with nonrecipients were 0.92 (95% CI 0.79-1.07) and 0.99 (95% CI 0.85-1.15), respectively. Furthermore, alpha-tocopherol or beta-carotene supplementation did not affect the risk of macrovascular complications or mortality of diabetic subjects during the 19 years follow-up time. In conclusion, in this study of older middle-aged male smokers, weight gain and weight fluctuation were independent risk factors for type 2 diabetes. Intake of antioxidants or serum alpha-tocopherol or beta-carotene concentrations were not associated with the risk of type 2 diabetes. Supplementation with of alpha-tocopherol or beta-carotene did not prevent type 2 diabetes. Neither did they prevent macrovascular complications, or mortality among diabetic subjects.

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Congenital long QT syndrome (LQTS) is a familial disorder characterized by ventricular repolarization that makes carriers vulnerable to malignant ventricular tachycardia and sudden cardiac death. The three main subtypes (LQT1, LQT2 and LQT3) constitute 95% of cases. The disorder is characterized by a prolonged QT interval in electrocardiograms (ECG), but a considerable portion are silent carriers presenting normal (QTc < 440 ms) or borderline (QTc < 470 ms) QT interval. Genetic testing is available only for 60-70% of patients. A number of pharmaceutical compounds also affect ventricular repolarization, causing a clinically similar disorder called acquired long QT syndrome. LQTS carriers - who already have impaired ventricular repolarization - are especially vulnerable. In this thesis, asymptomatic genotyped LQTS mutation carriers with non-diagnostic resting ECG were studied. The body surface potential mapping (BSPM) system was utilized for ECG recording, and signals were analyzed with an automated analysis program. QT interval length, and the end part of the T wave, the Tpe interval, was studied during exercise stress testing and an epinephrine bolus test. In the latter, T wave morphology was also analyzed. The effect of cetirizine was studied in LQTS carriers and also with supra- therapeutic dose in healthy volunteers. At rest, LQTS mutation carriers had a slightly longer heart rate adjusted QTc interval than healthy subjects (427 ± 31 ms and 379 ± 26 ms; p<0.001), but significant overlapping existed. LQT2 mutation carriers had a conspicuously long Tpe-interval (113 ± 24 ms; compared to 79 ± 11 ms in LQT1, 81 ± 17 ms in LQT3 and 78 ± 10 ms in controls; p<0.001). In exercise stress tests, LQT1 mutation carriers exhibit a long QT interval at high heart rates and during recovery, whereas LQT2 mutation carriers have a long Tpe interval at the beginning of exercise and at the end of recovery at low heart rates. LQT3 mutation carriers exhibit prominent shortening of both QT and Tpe intervals during exercise. A small epinephrine bolus revealed disturbed repolarization, especially in LQT2 mutation carriers, who developed prolonged Tpe intervals. A higher epinephrine bolus caused abnormal T waves with a different T wave profile in LQTS mutation carriers compared to healthy controls. These effects were seen in LQT3 as well, a group that may easily escape other provocative tests. In the cetirizine test, the QT and Tpe intervals were not prolonged in LQTS mutation carriers or in healthy controls. Subtype-specific findings in exercise test and epinephrine bolus test help to diagnose silent LQTS mutation carriers and to guide subtype-specific treatments. The Tpe interval, which signifies the repolarization process, seems to be a sensitive marker of disturbed repolarization along with the QT interval, which signifies the end of repolarization. This method may be used in studying compounds that are suspected to affect repolarization. Cetirizine did not adversely alter ventricular repolarization and would not be pro-arrhythmic in common LQT1 and LQT2 subtypes when used at its recommended doses.

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Pre-eclampsia is a pregnancy complication that affects about 5% of all pregnancies. It is known to be associated with alterations in angiogenesis -related factors, such as vascular endothelial growth factor (VEGF). An excess of antiangiogenic substances, especially the soluble receptor-1 of VEGF (sVEGFR-1), has been observed in maternal circulation after the onset of the disease, probably reflecting their increased placental production. Smoking reduces circulating concentrations of sVEGFR-1 in non-pregnant women, and in pregnant women it reduces the risk of pre-eclampsia. Soluble VEGFR-1 acts as a natural antagonist of VEGF and placental growth factor (PlGF) in human circulation, holding a promise for potential therapeutic use. In fact, it has been used as a model to generate a fusion protein, VEGF Trap , which has been found effective in anti-angiogenic treatment of certain tumors and ocular diseases. In the present study, we evaluated the potential use of maternal serum sVEGFR-1, Angiopoietin-2 (Ang-2) and endostatin, three central anti-angiogenic markers, in early prediction of subsequent pre-eclampsia. We also studied whether smoking affects circulating sVEGFR-1 concentrations in pregnant women or their first trimester placental secretion and expression in vitro. Last, in order to allow future discussion on the potential therapy based on sVEGFR-1, we determined the biological half-life of endogenous sVEGFR-1 in human circulation, and measured the concomitant changes in free VEGF concentrations. Blood or placental samples were collected from a total of 268 pregnant women between the years 2001 2007 in Helsinki University Central Hospital for the purposes above. The biomarkers were measured using commercially available enzyme-linked immunosorbent assays (ELISA). For the analyses of sVEGFR-1, Ang-2 and endostatin, a total of 3 240 pregnant women in the Helsinki area were admitted to blood sample collection during two routine ultrasoundscreening visits at 13.7 ± 0.5 (mean ± SD) and 19.2 ± 0.6 weeks of gestation. Of them, 49 women later developing pre-eclampsia were included in the study. Their disease was further classified as mild in 29 and severe in 20 patients. Isolated early-onset intrauterine growth retardation (IUGR) was diagnosed in 16 women with otherwise normal medical histories and uncomplicated pregnancies. Fifty-nine women remaining normotensive, non-proteinuric and finally giving birth to normal-weight infants were picked to serve as the control population of the study. Maternal serum concentrations of Ang-2, endostatin and sVEGFR-1, were increased already at 16 20 weeks of pregnancy, about 13 weeks before the clinical manifestation of preeclampsia. In addition, these biomarkers could be used to identify women at risk with a moderate precision. However, larger patient series are needed to determine whether these markers could be applied for clinical use to predict preeclampsia. Intrauterine growth retardation (IUGR), especially if noted at early stages of pregnancy and not secondary to any other pregnancy complication, has been suggested to be a form of preeclampsia compromising only the placental sufficiency and the fetus, but not affecting the maternal endothelium. In fact, IUGR and preeclampsia have been proposed to share a common vascular etiology in which factors regulating early placental angiogenesis are likely to play a central role. Thus, these factors have been suggested to be involved in the pathogenesis of IUGR. However, circulating sVEGFR-1, Ang-2 and endostatin concentrations were unaffected by subsequent IUGR at early second trimester. Furthermore, smoking was not associated with alterations in maternal circulating sVEGFR-1 or its placental production. The elimination of endogenous sVEGFR-1 after pregnancy was calculated from serial samples of eight pregnant women undergoing elective Caesarean section. As typical for proteins in human compartments, the elimination of sVEGFR-1 was biphasic, containing a rapid halflife of 3.4 h and a slow one of 29 h. The decline in sVEGFR-1 concentrations after mid-trimester legal termination of pregnancy was accompanied with a simultaneous increase in the serum levels of free VEGF so that within a few days after pregnancy VEGF dominated in the maternal circulation. Our study provides novel information on the kinetics of endogenous sVEGFR-1, which serves as a potential tool in the development of new strategies against diseases associated with angiogenic imbalance and alterations in VEGF signaling.

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Stroke is a major cause of death and disability, incurs significant costs to healthcare systems, and inflicts severe burden to the whole society. Stroke care in Finland has been described in several population-based studies between 1967 and 1998, but not since. In the PERFECT Stroke study presented here, a system for monitoring the Performance, Effectiveness, and Costs of Treatment episodes in Stroke was developed in Finland. Existing nationwide administrative registries were linked at individual patient level with personal identification numbers to depict whole episodes of care, from acute stroke, through rehabilitation, until the patients went home, were admitted to permanent institutional care, or died. For comparisons in time and between providers, patient case-mix was adjusted for. The PERFECT Stroke database includes 104 899 first-ever stroke patients over the years 1999 to 2008, of whom 79% had ischemic stroke (IS), 14% intracerebral hemorrhage (ICH), and 7% subarachnoid hemorrhage (SAH). A 18% decrease in the age and sex adjusted incidence of stroke was observed over the study period, 1.8% improvement annually. All-cause 1-year case-fatality rate improved from 28.6% to 24.6%, or 0.5% annually. The expected median lifetime after stroke increased by 2 years for IS patients, to 7 years and 7 months, and by 1 year for ICH patients, to 4 years 5 months. No change could be seen in median SAH patient survival, >10 years. Stroke prevalence was 82 000, 1.5% of total population of Finland, in 2008. Modern stroke center care was shown to be associated with a decrease in both death and risk of institutional care of stroke patients. Number needed to treat to prevent these poor outcomes at one year from stroke was 32 (95% confidence intervals 26 to 42). Despite improvements over the study period, more than a third of Finnish stroke patients did not have access to stroke center care. The mean first-year healthcare cost of a stroke patient was ~20 000 , and among survivors ~10 000 annually thereafter. Only part of this cost was incurred by stroke, as the same patients cost ~5000 over the year prior to stroke. Total lifetime costs after first-ever stroke were ~85 000 . A total of 1.1 Billion , 7% of all healthcare expenditure, is used in the treatment of stroke patients annually. Despite a rapidly aging population, the number of new stroke patients is decreasing, and the patients are more likely to survive. This is explained in part by stroke center care, which is effective, and should be made available for all stroke patients. It is possible, in a suitable setting with high-quality administrative registries and a common identifier, to avoid the huge workload and associated costs of setting up a conventional stroke registry, and still acquire a fairly comprehensive dataset on stroke care and outcome.

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Background Acute bacterial meningitis (BM) continues to be an important cause of childhood mortality and morbidity, especially in developing countries. Prognostic scales and the identification of risk factors for adverse outcome both aid in assessing disease severity. New antimicrobial agents or adjunctive treatments - except for oral glycerol - have essentially failed to improve BM prognosis. A retrospective observational analysis found paracetamol beneficial in adult bacteraemic patients, and some experts recommend slow β-lactam infusion. We examined these treatments in a prospective, double-blind, placebo-controlled clinical trial. Patients and methods A retrospective analysis included 555 children treated for BM in 2004 in the infectious disease ward of the Paediatric Hospital of Luanda, Angola. Our prospective study randomised 723 children into four groups, to receive a combination of cefotaxime infusion or boluses every 6 hours for the first 24 hours and oral paracetamol or placebo for 48 hours. The primary endpoints were 1) death or severe neurological sequelae (SeNeSe), and 2) deafness. Results In the retrospective study, the mortality of children with blood transfusion was 23% (30 of 128) vs. without blood transfusion 39% (109 of 282; p=0.004). In the prospective study, 272 (38%) of the children died. Of those 451 surviving, 68 (15%) showed SeNeSe, and 12% (45 of 374) were deaf. Whereas no difference between treatment groups was observable in primary endpoints, the early mortality in the infusion-paracetamol group was lower, with the difference (Fisher s exact test) from the other groups at 24, 48, and 72 hours being significant (p=0.041, 0.0005, and 0.005, respectively). Prognostic factors for adverse outcomes were impaired consciousness, dyspnoea, seizures, delayed presentation, and absence of electricity at home (Simple Luanda Scale, SLS); the Bayesian Luanda Scale (BLS) also included abnormally low or high blood glucose. Conclusions New studies concerning the possible beneficial effect of blood transfusion, and concerning longer treatment with cefotaxime infusion and oral paracetamol, and a study to validate our simple prognostic scales are warranted.

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Background: The improved prognosis of early preterm birth has created a generation of surviving very low birth weight (< 1500 g, VLBW) infants whose health risks in adulthood are poorly known. Of every 1000 live-born infants in Finland, about 8 are born at VLBW. Variation in birth weight, even within the normal range, relates to considerable variation in the risk for several common adult disorders, including cardiovascular disease and osteoporosis. Small preterm infants frequently exhibit severe postnatal or prenatal growth retardation, or both. Much reason for concern thus exists, regarding adverse health effects in surviving small preterm infants later lives. We studied young adults, aiming at exploring whether VLBW birth and postnatal events after such a birth are associated with higher levels of risk factors for cardiovascular disease or osteoporosis. Subjects and Methods: A follow-up study for VLBW infants began in 1978; by the end of 1985, 335 VLBW survivors at Helsinki University Central Hospital participated in the follow-up. Their gestational ages ranged from 24 to 35 weeks, mean 29.2 and standard deviation 2.2 weeks. In 2004, we invited for a clinic visit 255 subjects, aged 18 to 27, who still lived in the greater Helsinki area. From the same birth hospitals, we also invited 314 term-born controls of similar age and sex. These two study groups underwent measurements of body size and composition, function of brachial arterial endothelium (flow-mediated dilatation, FMD) and carotid artery intima-media thickness (cIMT) by ultrasound. In addition, we measured plasma lipid concentrations, ambulatory blood pressure, fasting insulin, glucose tolerance and, by dual-energy x-ray densitometry, bone-mineral density. Results: 172 control and 166 VLBW participants underwent lipid measurements and a glucose tolerance test. VLBW adults fasting insulin (adjusted for body mass index) was 12.6% (95% confidence interval, 0.8 to 25.8) higher than that of the controls. The glucose and insulin concentrations 120 minutes after 75 g glucose ingestion showed similar differences (N=332) (I). VLBW adults had 3.9 mmHg (1.3 to 6.4) higher office systolic blood pressure, 3.5 mmHg (1.7 to 5.2) higher office diastolic blood pressure (I), and, when adjusted for body mass index and height, 3.1 mmHg (0.5 to 5.5) higher 24-hour mean systolic blood pressure (N=238) (II). VLBW birth was associated neither with HDL- or total cholesterol nor triglyceride concentrations (N=332) (I), nor was it associated with a low FMD or a high cIMT (N=160) (III). VLBW adults had 0.51-unit (0.28 to 0.75) lower lumbar spine Z scores and 0.56-unit (0.34 to 0.78) lower femoral neck Z scores (N=283). Adjustments for size attenuated the differences, but only partially (IV). Conclusions: These results imply that those born at VLBW, although mostly healthy as young adults, already bear several risk factors for chronic adult disease. The significantly higher fasting insulin level in adults with VLBW suggests increased insulin resistance. The higher blood pressure in young adults born at VLBW may indicate they later are at risk for hypertension, although their unaffected endothelial function may be evidence for some form of protection from cardiovascular disease. Lower bone mineral density around the age of peak bone mass may suggest increased risk for later osteoporotic fractures. Because cardiovascular disease and osteoporosis are frequent, and their prevention is relatively cheap and safe, one should focus on prevention now. When initiated early, preventive measures are likely to have sufficient time to be effective in preventing or postponing the onset of chronic disease.

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Hantaviruses have a tri-segmented negative-stranded RNA genome. The S segment encodes the nucleocapsid protein (N), M segment two glycoproteins, Gn and Gc, and the L segment the RNA polymerase. Gn and Gc are co-translationally cleaved from a precursor and targeted to the cis-Golgi compartment. The Gn glycoprotein consists of an external domain, a transmembrane domain and a C-terminal cytoplasmic domain. In addition, the S segment of some hantaviruses, including Tula and Puumala virus, have an open reading frame (ORF) encoding a nonstructural potein NSs that can function as a weak interferon antagonist. The mechanisms of hantavirus-induced pathogenesis are not fully understood but it is known that both hemorrhagic fever with renal syndrome (HFRS) and hantavirus (cardio) pulmonary syndrome (HCPS) share various features such as increased capillary permeability, thrombocytopenia and upregulation of TNF-. Several hantaviruses have been reported to induce programmed cell death (apoptosis), such as TULV-infected Vero E6 cells which is known to be defective in interferon signaling. Recently reports describing properties of the hantavirus Gn cytoplasmic tail (Gn-CT) have appeared. The Gn-CT of hantaviruses contains animmunoreceptor tyrosine-based activation motif (ITAM) which directs receptor signaling in immune and endothelial cells; and contain highly conserved classical zinc finger domains which may have a role in the interaction with N protein. More functions of Gn protein have been discovered, but much still remains unknown. Our aim was to study the functions of Gn protein from several aspects: synthesis, degradation and interaction with N protein. Gn protein was reported to inhibit interferon induction and amplication. For this reason, we also carried out projects studying the mechanisms of IFN induction and evasion by hantavirus. We first showed degradation and aggresome formation of the Gn-CT of the apathogenic TULV. It was reported earlier that the degradation of Gn-CT is related to the pathogenicity of hantavirus. We found that the Gn-CT of the apathogenic hantaviruses (TULV, Prospect Hill virus) was degraded through the ubiquitin-proteasome pathway, and TULV Gn-CT formed aggresomes upon treatment with proteasomal inhibitor. Thus the results suggest that degradation and aggregation of the Gn-CT may be a general property of most hantaviruses, unrelated to pathogenicity. Second, we investigated the interaction of TULV N protein and the TULV Gn-CT. The Gn protein is located on the Golgi membrane and its interaction with N protein has been thought to determine the cargo of the hantaviral ribonucleoprotein which is an important step in virus assembly, but direct evidence has not been reported. We found that TULV Gn-CT fused with GST tag expressed in bacteria can pull-down the N protein expressed in mammalian cells; a mutagenesis assay was carried out, in which we found that the zinc finger motif in Gn-CT and RNA-binding motif in N protein are indispensable for the interaction. For the study of mechanisms of IFN induction and evasion by Old World hantavirus, we found that Old World hantaviruses do not produce detectable amounts of dsRNA in infected cells and the 5 -termini of their genomic RNAs are monophosphorylated. DsRNA and tri-phosphorylated RNA are considered to be critical activators of innate immnity response by interacting with PRRs (pattern recognition receptors). We examined systematically the 5´-termini of hantavirus genomic RNAs and the dsRNA production by different species of hantaviruses. We found that no detectable dsRNA was produced in cells infected by the two groups of the old world hantaviruses: Seoul, Dobrava, Saaremaa, Puumala and Tula. We also found that the genomic RNAs of these Old World hantaviruses carry 5´-monophosphate and are unable to trigger interferon induction. The antiviral response is mainly mediated by alpha/beta interferon. Recently the glycoproteins of the pathogenic hantaviruses Sin Nombre and New York-1 viruses were reported to regulate cellular interferon. We found that Gn-CT can inhibit the induction of IFN activation through Toll-like receptor (TLR) and retinoic acid-inducible gene I-like RNA helicases (RLH) pathway and that the inhibition target lies at the level of TANK-binding kinase 1 (TBK-1)/ IKK epislon complex and myeloid differentiation primary response gene (88) (MyD88) / interferon regulatory factor 7 (IRF-7) complex.

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Asthma is a chronic inflammatory disorder of the airways. Remodelling in asthma is defined as the structural changes seen in the airways of asthmatics in comparison to healthy controls. Progressive loss of lung function also seen in asthma might be caused by remodelling. The research aims of this thesis were to investigate inflammation and remodelling in the airways of different types of asthmatics and smokers. The association between inflammation and remodelling was also examined in a mouse model of allergic airway inflammation. Healthy smokers showed increased numbers of macrophages in the BAL with no changes in the inflammatory cells in biopsies. Macrophages seemed to be quite quiescent, since mRNA expression for a wide variety of inflammatory mediators, especially chemokines CCL3, CCL4, CCL5 and CCL20, secreted by macrophages was significantly lower than in healthy non-smokers. Attenuated macrophage activity in the airway lumen may render smokers more susceptible to airway infections and have an impact on the development of other airway pathology. Patients with diisocyanate-induced asthma (DIA) on inhaled corticosteroids (ICS) who still had non-specific bronchial hyperreactivity (NSBHR) at the end of the follow-up showed increased expression of TNF-α, IL-6 and IL-15 mRNA in BAL cells compared to those without NSBHR. In addition to being markers for poor prognosis and possible slight glucocorticoid resistance, these cytokines might aid in guiding the treatment of DIA. The increase in the thickness of tenascin-C layer in the bronchial basement membrane (BM) was much less than usually seen in other types of asthma, which might not make tenascin-C a good marker for DIA. OVA-induced tenascin-C expression in the lung was attenuated in STAT4-/- mice with impaired Th1-type immunity compared to WT mice. Interestingly, STAT6-/- mice with impaired Th2-type immunity showed tenascin-C expression levels similar to those of WT mice. The clearest difference between these two knockout strains in response to OVA was that STAT4-/- mice exhibited no upregulation of IFN-γ and TNF-α mRNA expression. Thus, tenascin-C expression was unexpectedly more related to Th1 type reactions. In vitro studies confirmed the results. Human fibroblasts stimulated by TNF-α and IFN-γ showed increased expression of tenascin-C. Patients with newly diagnosed asthma showed increased expression of laminin α2 in the bronchial BM in comparison to patients with asthma symptoms only and healthy controls. Both patients with asthma and those with only asthma symptoms showed increased expression of the laminin β2 chain in comparison to controls. Thus, laminin α2 expression differentiated patients with clinical asthma from patients with symptoms only. Furthermore, the expression of laminin α2 and β2 was associated with NSBHR, linking very specific remodelling events to clinical findings.

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Background: The improved prognosis of early preterm birth has created a generation of surviving very low birth weight (PIENEMPI KUIN 1500 g, VLBW) infants whose health risks in adulthood are poorly known. Of every 1000 live-born infants in Finland, about 8 are born at VLBW. Variation in birth weight, even within the normal range, relates to considerable variation in the risk for several common adult disorders, including cardiovascular disease and osteoporosis. Small preterm infants frequently exhibit severe postnatal or prenatal growth retardation, or both. Much reason for concern thus exists, regarding adverse health effects in surviving small preterm infants later lives. We studied young adults, aiming at exploring whether VLBW birth and postnatal events after such a birth are associated with higher levels of risk factors for cardiovascular disease or osteoporosis. Subjects and Methods: A follow-up study for VLBW infants began in 1978; by the end of 1985, 335 VLBW survivors at Helsinki University Central Hospital participated in the follow-up. Their gestational ages ranged from 24 to 35 weeks, mean 29.2 and standard deviation 2.2 weeks. In 2004, we invited for a clinic visit 255 subjects, aged 18 to 27, who still lived in the greater Helsinki area. From the same birth hospitals, we also invited 314 term-born controls of similar age and sex. These two study groups underwent measurements of body size and composition, function of brachial arterial endothelium (flow-mediated dilatation, FMD) and carotid artery intima-media thickness (cIMT) by ultrasound. In addition, we measured plasma lipid concentrations, ambulatory blood pressure, fasting insulin, glucose tolerance and, by dual-energy x-ray densitometry, bone-mineral density. Results: 172 control and 166 VLBW participants underwent lipid measurements and a glucose tolerance test. VLBW adults fasting insulin (adjusted for body mass index) was 12.6% (95% confidence interval, 0.8 to 25.8) higher than that of the controls. The glucose and insulin concentrations 120 minutes after 75 g glucose ingestion showed similar differences (N=332) (I). VLBW adults had 3.9 mmHg (1.3 to 6.4) higher office systolic blood pressure, 3.5 mmHg (1.7 to 5.2) higher office diastolic blood pressure (I), and, when adjusted for body mass index and height, 3.1 mmHg (0.5 to 5.5) higher 24-hour mean systolic blood pressure (N=238) (II). VLBW birth was associated neither with HDL- or total cholesterol nor triglyceride concentrations (N=332) (I), nor was it associated with a low FMD or a high cIMT (N=160) (III). VLBW adults had 0.51-unit (0.28 to 0.75) lower lumbar spine Z scores and 0.56-unit (0.34 to 0.78) lower femoral neck Z scores (N=283). Adjustments for size attenuated the differences, but only partially (IV). Conclusions: These results imply that those born at VLBW, although mostly healthy as young adults, already bear several risk factors for chronic adult disease. The significantly higher fasting insulin level in adults with VLBW suggests increased insulin resistance. The higher blood pressure in young adults born at VLBW may indicate they later are at risk for hypertension, although their unaffected endothelial function may be evidence for some form of protection from cardiovascular disease. Lower bone mineral density around the age of peak bone mass may suggest increased risk for later osteoporotic fractures. Because cardiovascular disease and osteoporosis are frequent, and their prevention is relatively cheap and safe, one should focus on prevention now. When initiated early, preventive measures are likely to have sufficient time to be effective in preventing or postponing the onset of chronic disease.

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Although improved outcomes for children on peritoneal dialysis (PD) have been seen in recent years, the youngest patients continue to demonstrate inferior growth, more frequent infections, more neurological sequelae, and higher mortality compared to older children. Also, maintain-ing normal intravascular volume status, especially in anuric patients, has proven difficult. This study was designed to treat and monitor these youngest PD patients, which are relatively many due to the high prevalence of congenital nephrotic syndrome of the Finnish type (CNF, NPHS1) in Finland, with a strict protocol, to evaluate the results and to improve metabolic balance, growth, and development. A retrospective analysis of 23 children under two years of age at onset of PD, treated between 1995 and 2000, was performed to obtain a control population for our prospective PD study. Respectively, 21 patients less than two years of age at the beginning of PD were enrolled in prospective studies between 2001 and 2005. Medication for uremia and nutrition were care-fully adjusted during PD. Laboratory parameters and intravascular volume status were regu-larly analyzed. Growth was analyzed and compared with midparental height. In a prospective neurological study, the risk factors for development and the neurological development was determined. Brain images were surveyed. Hearing was tested. In a retrospective neurological study, the data of six NPHS1 patients with a congruent neurological syndrome was analyzed. All these patients had a serious dyskinetic cerebral palsy-like syndrome with muscular dysto-nia and athetosis (MDA). They also had a hearing defect. Metabolic control was mainly good in both PD patient groups. Hospitalization time shortened clearly. The peritonitis rate diminished. Hypertension was a common problem. Left ventricular hypertrophy decreased during the prospective study period. None of the patients in either PD group had pulmonary edema or dialysis-related seizures. Growth was good and catch-up growth was documented in most patients in both patient groups during PD. Mortality was low (5% in prospective and 9% in retrospective PD patients). In the prospective PD patient group 11 patients (52%) had some risk factor for their neuro-development originating from the predialysis period. The neurological problems, detected be-fore PD, did not worsen during PD and none of the patients developed new neurological com-plications during PD. Brain infarcts were detected in four (19%) and other ischemic lesions in three patients (14%). At the end of this study, 29% of the prospectively followed patients had a major impairment of their neurodevelopment and 43% only minor impairment. In the NPHS1+MDA patients, no clear explanation for the neurological syndrome was found. The brain MRI showed increased signal intensity in the globus pallidus area. Kernic-terus was contemplated to be causative in the hypoproteinemic newborns but it could not be proven. Mortality was as high as 67%. Our results for young PD patients were promising. Metabolic control was acceptable and growth was good. However, the children were significantly smaller when compared to their midparental height. Although many patients were found to have neurological impairment at the end of our follow-up period, PD was a safe treatment whereby the neurodevelopment did not worsen during PD.

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Several orthopoxviruses (OPV) and Borna disease virus (BDV) are enveloped, zoonotic viruses with a wide geographical distribution. OPV antibodies cross-react, and former smallpox vaccination has therefore protected human populations from another OPV infection, rodent-borne cowpox virus (CPXV). Cowpox in humans and cats usually manifests as a mild, self-limiting dermatitis and constitutional symptoms, but it can be severe and even life-threatening in the immunocompromised. Classical Borna disease is a progressive meningoencephalomyelitis in horses and sheep known in central Europe for centuries. Nowadays the virus or its close relative infects humans and also several other species in central Europe and elsewhere, but the existence of human Borna disease with its suspected neuropsychiatric symptoms is controversial. The epidemiology of BDV is largely unknown, and the present situation is even more intriguing following the recent detection of several-million-year-old, endogenized BDV genes in primate and various other vertebrate genomes. The aims of this study were to elucidate the importance of CPXV and BDV in Finland and in possible host species, and particularly to 1) establish relevant methods for the detection of CPXV and other OPVs as well as BDV in Finland, 2) determine whether CPXV and BDV exist in Finland, 3) discover how common OPV immunity is in different age groups in Finland, 4) characterize possible disease cases and clarify their epidemiological context, 5) establish the hosts and possible reservoir species of these viruses and their geographical distribution in wild rodents, and 6) elucidate the infection kinetics of BDV in the bank vole. An indirect immunofluorescence assay and avidity measurement were established for the detection, timing and verification of OPV or BDV antibodies in thousands of blood samples from humans, horses, ruminants, lynxes, gallinaceous birds, dogs, cats and rodents. The mostly vaccine-derived OPV seroprevalence was found to decrease gradually according to the year of birth of the sampled human subjects from 100% to 10% in those born after 1977. On the other hand, OPV antibodies indicating natural contact with CPXV or other OPVs were commonly found in domestic and wild animals: the horse, cow, lynx, dog, cat and, with a prevalence occasionally even as high as 92%, in wild rodents, including some previously undetected species and new regions. Antibodies to BDV were detected in humans, horses, a dog, cats, and for the first time in wild rodents, such as bank voles (Myodes glareolus). Because of the controversy within the human Borna disease field, extra verification methods were established for BDV antibody findings: recombinant nucleocapsid and phosphoproteins were produced in Escherichia coli and in a baculovirus system, and peptide arrays were additionally applied. With these verification assays, Finnish human, equine, feline and rodent BDV infections were confirmed. Taken together, wide host spectra were evident for both OPV and BDV infections based on the antibody findings, and OPV infections were found to be geographically broadly distributed. PCR amplification methods were utilised for hundreds of blood and tissue samples. The methods included conventional, nested and real-time PCRs with or without the reverse transcription step and detecting four or two genes of OPVs and BDV, respectively. OPV DNA could be amplified from two human patients and three bank voles, whereas no BDV RNA was detected in naturally infected individuals. Based on the phylogenetic analyses, the Finnish OPV sequences were closely related although not identical to a Russian CPXV isolate, and clearly different from other CPXV strains. Moreover, the Finnish sequences only equalled each other, but the short amplicons obtained from German rodents were identical to monkeypox virus, in addition to German CPXV variants. This reflects the close relationship of all OPVs. In summary, RNA of the Finnish BDV variant could not be detected with the available PCR methods, but OPV DNA infrequently could. The OPV species infecting the patients of this study was proven to be CPXV, which is most probably also responsible for the rodent infections. Multiple cell lines and some newborn rodents were utilised in the isolation of CPXV and BDV from patient and wildlife samples. CPXV could be isolated from a child with severe, generalised cowpox. BDV isolation attempts from rodents were unsuccessful in this study. However, in parallel studies, a transient BDV infection of cells inoculated with equine brain material was detected, and BDV antigens discovered in archival animal brains using established immunohistology. Thus, based on several independent methods, both CPXV and BDV (or a closely related agent) were shown to be present in Finland. Bank voles could be productively infected with BDV. This experimental infection did not result in notable pathological findings or symptoms, despite the intense spread of the virus in the central and peripheral nervous system. Infected voles commonly excreted the virus in urine and faeces, which emphasises their possible role as a BDV reservoir. Moreover, BDV RNA was regularly reverse transcribed into DNA in bank voles, which was detected by amplifying DNA by PCR without reverse transcription, and verified with nuclease treatments. This finding indicates that BDV genes could be endogenized during an acute infection. Although further transmission studies are needed, this experimental infection demonstrated that the bank vole can function as a potential BDV reservoir. In summary, multiple methods were established and applied in large panels to detect two zoonoses novel to Finland: cowpox virus and Borna disease virus. Moreover, new information was obtained on their geographical distribution, host spectrum, epidemiology and infection kinetics.

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Uveal melanoma (UM) is the second most common primary intraocular cancer worldwide. It is a relatively rare cancer, but still the second most common type of primary malignant melanoma in humans. UM is a slowly growing tumor, and gives rise to distant metastasis mainly to the liver via the bloodstream. About 40% of patients with UM die of metastatic disease within 10 years of diagnosis, irrespective of the type of treatment. During the last decade, two main lines of research have aimed to achieve enhanced understanding of the metastasis process and accurate prognosis of patients with UM. One emphasizes the characteristics of tumor cells, particularly their nucleoli, and markers of proliferation, and the other the characteristics of tumor blood vessels. Of several morphometric measurements, the mean diameter of the ten largest nucleoli (MLN) has become the most widely applied. A large MLN has consistently been associated with high likelihood of dying from UM. Blood vessels are of paramount importance in metastasis of UM. Different extravascular matrix patterns can be seen in UM, like loops and networks. This presence is associated with death from metastatic melanoma. However, the density of microvessels is also of prognostic importance. This study was undertaken to help understanding some histopathological factors which might contribute to developing metastasis in UM patients. Factors which could be related to tumor progression to metastasis disease, namely nucleolar size, MLN, microvascular density (MVD), cell proliferation, and The Insulin-like Growth Factor 1 Receptor(IGF-1R), were investigated. The primary aim of this thesis was to study the relationship between prognostic factors such as tumor cell nucleolar size, proliferation, extravascular matrix patterns, and dissemination of UM, and to assess to what extent there is a relationship to metastasis. The secondary goal was to develop a multivariate model which includes MLN and cell proliferation in addition to MVD, and which would fit better with population-based, melanoma-related survival data than previous models. I studied 167 patients with UM, who developed metastasis even after a very long time following removal of the eye, metastatic disease was the main cause of death, as documented in the Finnish Cancer Registry and on death certificates. Using an independent population-based data set, it was confirmed that MLN and extravascular matrix loops and networks were unrelated, independent predictors of survival in UM. Also, it has been found that multivariate models including MVD in addition to MLN fitted significantly better with survival data than models which excluded MVD. This supports the idea that both the characteristics of the blood vessels and the cells are important, and the future direction would be to look for the gene expression profile, whether it is associated more with MVD or MLN. The former relates to the host response to the tumor and may not be as tightly associated with the gene expression profile, yet most likely involved in the process of hematogenous metastasis. Because fresh tumor material is needed for reliable genetic analysis, such analysis could not be performed Although noninvasive detection of certain extravascular matrix patterns is now technically possible,in managing patients with UM, this study and tumor genetics suggest that such noninvasive methods will not fully capture the process of clinical metastasis. Progress in resection and biopsy techniques is likely in the near future to result in fresh material for the ophthalmic pathologist to correlate angiographic data, histopathological characteristics such as MLN, and genetic data. This study supported the theory that tumors containing epithelioid cells grow faster and have poorer prognosis when studied by cell proliferation in UM based on Ki-67 immunoreactivity. Cell proliferation index fitted best with the survival data when combined with MVD, MLN, and presence of epithelioid cells. Analogous with the finding that high MVD in primary UM is associated with shorter time to metastasis than low MVD, high MVD in hepatic metastasis tends to be associated with shorter survival after diagnosis of metastasis. Because the liver is the main organ for metastasis from UM, growth factors largely produced in the liver hepatocyte growth factor, epidermal growth factor and insulin-like growth factor-1 (IGF-1) together with their receptors may have a role in the homing and survival of metastatic cells. Therefore the association between immunoreactivity for IGF-1R in primary UM and metastatic death was studied. It was found that immunoreactivity for IGF-IR did not independently predict metastasis from primary UM in my series.

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Tinnitus is a frequent consequence of noise trauma. Usually, however, the main focus regarding the consequences of noise trauma is placed on hearing loss, instead of tinnitus. The objectives of the present study were to assess various aspects of noise-related tinnitus in Finland, such as to determine the main causes of conscript acute acoustic traumas (AAT) in the military, assess tinnitus prevalence after noise trauma, characterize long-term AAT-related tinnitus prevalence and characteristics, assess occupational tinnitus, and evaluate the efficacy of hearing protection regulations in preventing hearing loss and tinnitus. The study comprised several independent noise-exposed groups: conscripts performing their military duty, former conscripts who suffered an AAT over a decade earlier, bomb explosion victims, and retired army personnel. Tinnitus questionnaires were used to assess tinnitus prevalence and characteristics. For occupational tinnitus, occupational noise-induced hearing loss (NIHL) reports to the Finnish Institute of Occupational Health were reviewed. Tinnitus is a common result of AAT, blast exposure and long-term noise exposure. Despite hearing protection regulations, up to hundreds of AATs occur annually among conscripts in the Finnish Defence Forces (FDF). The most common cause is an accidental shot, accounting for approximately half of the cases. Conscript AATs are mainly due to accidental shots, while the ear is unprotected. Only seldom is an AAT due to negligence. The most common causative weapon of conscript AATs is the assault rifle, accounting for 81% of conscript AATs. After AAT, the majority of tinnitus cases resolve during military service and become asymptomatic. However, in one-fifth of the cases, tinnitus persists, causing problems such as sleeping and concentration difficulties in many. In Finland, occupational tinnitus often remains unreported in conjunction with NIHL reports. In a survey of occupational NIHL cases, tinnitus was mentioned in only four per cent. However, a subsequent inquiry revealed that almost 90% in fact had tinnitus, indicating that most cases remained undetected and unreported. The best way to prevent noise-related tinnitus is prevention of noise trauma. In the military, hearing protection guidelines have been revised several times over the years. These regulations have been effective in reducing hearing loss of professional soldiers. There has also been a reduction in cases with tinnitus, but the decrease was not significant. However, with improved hearing protection regulations, a significant reduction in the risk of more serious, disturbing tinnitus was observed.

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Transcription factors play a key role in tumor development, in which dysfunction of genes regulating tissue growth and differentiation is a central phenomenon. The GATA family of transcription factors consists of six members that bind to a consensus DNA sequence (A/T)GATA(A/G) in gene promoters and enhancers. The two GATA factors expressed in the adrenal cortex are GATA-4 and GATA-6. In both mice and humans, GATA-4 can be detected only during the fetal period, whereas GATA-6 expression is abundant both throughout development and in the adult. It is already established that GATA factors are important in both normal development and tumorigenesis of several endocrine organs, and expression of GATA-4 and GATA-6 is detected in adrenocortical tumors. The aim of this study was to elucidate the function of these factors in adrenocortical tumor growth. In embryonal development, the adrenocortical cells arise and differentiate from a common pool with gonadal steroidogenic cells, the urogenital ridge. As the adult adrenal cortex undergoes constant renewal, it is hypothesized that undifferentiated adrenocortical progenitor cells reside adjacent to the adrenal capsule and give rise to daughter cells that differentiate and migrate centripetally. A diverse array of hormones controls the differentiation, growth and survival of steroidogenic cells in the adrenal gland and the gonads. Factors such as luteinizing hormone and inhibins, traditionally associated with gonadal steroidogenic cells, can also influence the function of adrenocortical cells in physiological and pathophysiological states. Certain inbred strains of mice develop subcapsular adrenocortical tumors in response to gonadectomy. In this study, we found that these tumors express GATA-4, normally absent from the adult adrenal cortex, while GATA-6 expression is downregulated. Gonadal markers such as luteinizing hormone receptor, anti-Müllerian hormone and P450c17 are also expressed in the neoplastic cells, and the tumors produce gonadal hormones. The tumor cells have lost the expression of melanocortin-2 receptor and the CYP enzymes necessary for the synthesis of corticosterone and aldosterone. By way of xenograft studies utilizing NU/J nude mice, we confirmed that chronic gonadotropin elevation is sufficient to induce adrenocortical tumorigenesis in susceptible inbred strains. Collectively, these studies suggest that subcapsular adrenocortical progenitor cells can, under certain conditions, adopt a gonadal fate. We studied the molecular mechanisms involved in gene regulation in endocrine cells in order to elucidate the role of GATA factors in endocrine tissues. Ovarian granulosa cells express both GATA-4 and GATA-6, and the TGF-β signaling pathway is active in these cells. Inhibin-α is both a target gene for, and an atypical or antagonistic member of the TGF-β growth factor superfamily. In this study, we show that GATA-4 is required for TGF-β-mediated inhibin-α promoter activation in granulosa cells, and that GATA-4 physically interacts with Smad3, a TGF-β downstream protein. Apart from the regulation of steroidogenesis and other events in normal tissues, TGF-β signaling is implicated in tumors of multiple organs, including the adrenal cortex. Another signaling pathway found often to be aberrantly active in adrenocortical tumors is the Wnt pathway. As both of these pathways regulate the expression of inhibin-α, a transcriptional target for GATA-4 and GATA-6, we wanted to investigate whether GATA factors are associated with the components of these signaling cascades in human adrenocortical tumors. We found that the expression of Wnt co-receptors LRP5 and LRP6, Smad3, GATA-6 and SF-1 was diminished in adrenocortical carcinomas with poor outcome. All of these factors drive inhibin-α expression, and their expression in adrenocortical tumors correlated with that of inhibin-α. The results support a tumor suppressor role previously suggested for inhibin-α in the mouse adrenal cortex, and offer putative pathways associated with adrenocortical tumor aggressiveness. Unraveling the role of GATA factors and associated molecules in human and mouse adrenocortical tumors could ultimately contribute to the development of diagnostic tools and future therapies for these diseases.

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Urinary incontinence is a common problem, affecting one third of the women at least at some time during their lives. The prevalence of urinary incontinence increases with advancing age, and the everyday impact of incontinence on women and on health services is enormous. Urinary incontinence is usually divided into three different subtypes, of which stress urinary incontinence (SUI) is the most common. Surgical treatment is often needed to cure SUI, and modern mid-urethral sling procedures give the possibility to cure this condition with a low risk of adverse events, a problem often associated with the so-called traditional incontinence operations. Life expectancy among women in Western countries has grown beyond 80 years of age. Long-term efficacy of treatment options for urinary incontinence therefore becomes an important issue in a world with limited eco-nomic resources. The purpose of the present study was to prospectively evaluate the long-term efficacy and safety of the first minimally invasive mid-urethral tape procedure, the Tension-free Vaginal Tape (TVT) procedure. The long-term (5-year) follow-up results of the TVT procedure as a repeat operation af-ter an unsuccessful mid-urethral tape operation were studied and the reasons for failure of the first operation were analyzed. Another purpose was to compare the original TVT procedure with a newer modification, the Tension-free Vaginal Tape Obturator (TVT-O) procedure within a multi-centre, randomized context in order to find out possible differences between these procedures re-garding efficacy and complications and the effects on symptoms of urgency. The first study of the present thesis is a prospective, Nordic, three-centre follow-up study of 90 women suffering from SUI, who were treated by means of the TVT procedure. The mean follow-up time was more than eleven years, and the study is the first to be published in connection with more than ten years of follow-up. The second study is a retrospective analysis of 26 women who were treated with a repeat TVT procedure after an unsuccessful primary mid-urethral tape procedure. The third and fourth studies concern 273 women in seven centres in Finland who were ran-domly assigned to the TVT and TVT-O procedures, the 3-year follow-up results of which are pre-sented in this thesis. After eleven years of follow-up, 90% of the women had a negative cough stress test result and a negative 24-h pad test result. The subjective cure rate measured as the women s global impression of cure was 77%, the rate of improvement 20%, and only 3% thought that the treatment had failed. No late-onset adverse effects were found. The repeat TVT procedure was successful in 75% of the cases when women who were cured and women who were significantly improved were included. The reasons for failure of the first operation could be separated into four different groups: tape material-related, operation technique-related, concomitant illness-related and a group with no identifiable reason. There were no intra-operative complications during the repeat operation. In the randomized trial comparing the TVT with the TVT-O procedure a cough stress test results were negative in 94.6% and 89.5% of the women in the two groups, respectively, after a 3-year follow-up period. There were no statistical differences in the cure rate or the rate of complications be-tween the two procedures. Symptoms of urgency were analyzed more closely and the main finding was that the prevalence of urgency symptoms decreased significantly after both mid-urethral sling procedures. The TVT operation was found to be an effective and safe procedure even after eleven years of follow-up. Long-term follow-up after a repeat TVT procedure revealed that the TVT procedure can well be considered after an unsuccessful mid-urethra tape procedure, because 75% of the patients showed significantly improvement of their incontinence. The TVT and TVT-O procedures showed no statistically significant differences in efficacy and rate of complications after three years of follow-up. In most cases these procedures alleviate preoperative symptoms of urgency and the risk of developing de novo urgency is low.