Individualized immunosuppression after renal transplantation in childhood

Pediatric renal transplantation (TX) has evolved greatly during the past few decades, and today TX is considered the standard care for children with end-stage renal disease. In Finland, 191 children had received renal transplants by October 2007, and 42% of them have already reached adulthood. Improvements in treatment of end-stage renal disease, surgical techniques, intensive care medicine, and in immunosuppressive therapy have paved the way to the current highly successful outcomes of pediatric transplantation. In children, the transplanted graft should last for decades, and normal growth and development should be guaranteed. These objectives set considerable requirements in optimizing and fine-tuning the post-operative therapy. Careful optimization of immunosuppressive therapy is crucial in protecting the graft against rejection, but also in protecting the patient against adverse effects of the medication. In the present study, the results of a retrospective investigation into individualized dosing of immunosuppresive medication, based on pharmacokinetic profiles, therapeutic drug monitoring, graft function and histology studies, and glucocorticoid biological activity determinations, are reported. Subgroups of a total of 178 patients, who received renal transplants in 1988 2006 were included in the study. The mean age at TX was 6.5 years, and approximately 26% of the patients were <2 years of age. The most common diagnosis leading to renal TX was congenital nephrosis of the Finnish type (NPHS1). Pediatric patients in Finland receive standard triple immunosuppression consisting of cyclosporine A (CsA), methylprednisolone (MP) and azathioprine (AZA) after renal TX. Optimal dosing of these agents is important to prevent rejections and preserve graft function in one hand, and to avoid the potentially serious adverse effects on the other hand. CsA has a narrow therapeutic window and individually variable pharmacokinetics. Therapeutic monitoring of CsA is, therefore, mandatory. Traditionally, CsA monitoring has been based on pre-dose trough levels (C0), but recent pharmacokinetic and clinical studies have revealed that the immunosuppressive effect may be related to diurnal CsA exposure and blood CsA concentration 0-4 hours after dosing. The two-hour post-dose concentration (C2) has proved a reliable surrogate marker of CsA exposure. Individual starting doses of CsA were analyzed in 65 patients. A recommended dose based on a pre-TX pharmacokinetic study was calculated for each patient by the pre-TX protocol. The predicted dose was clearly higher in the youngest children than in the older ones (22.9±10.4 and 10.5±5.1 mg/kg/d in patients <2 and >8 years of age, respectively). The actually administered oral doses of CsA were collected for three weeks after TX and compared to the pharmacokinetically predicted dose. After the TX, dosing of CsA was adjusted according to clinical parameters and blood CsA trough concentration. The pharmacokinetically predicted dose and patient age were the two significant parameters explaining post-TX doses of CsA. Accordingly, young children received significantly higher oral doses of CsA than the older ones. The correlation to the actually administered doses after TX was best in those patients, who had a predicted dose clearly higher or lower (> ±25%) than the average in their age-group. Due to the great individual variation in pharmacokinetics standardized dosing of CsA (based on body mass or surface area) may not be adequate. Pre-Tx profiles are helpful in determining suitable initial CsA doses. CsA monitoring based on trough and C2 concentrations was analyzed in 47 patients, who received renal transplants in 2001 2006. C0, C2 and experienced acute rejections were collected during the post-TX hospitalization, and also three months after TX when the first protocol core biopsy was obtained. The patients who remained rejection free had slightly higher C2 concentrations, especially very early after TX. However, after the first two weeks also the trough level was higher in the rejection-free patients than in those with acute rejections. Three months after TX the trough level was higher in patients with normal histology than in those with rejection changes in the routine biopsy. Monitoring of both the trough level and C2 may thus be warranted to guarantee sufficient peak concentration and baseline immunosuppression on one hand and to avoid over-exposure on the other hand. Controlling of rejection in the early months after transplantation is crucial as it may contribute to the development of long-term allograft nephropathy. Recently, it has become evident that immunoactivation fulfilling the histological criteria of acute rejection is possible in a well functioning graft with no clinical sings or laboratory perturbations. The influence of treatment of subclinical rejection, diagnosed in 3-month protocol biopsy, to graft function and histology 18 months after TX was analyzed in 22 patients and compared to 35 historical control patients. The incidence of subclinical rejection at three months was 43%, and the patients received a standard rejection treatment (a course of increased MP) and/or increased baseline immunosuppression, depending on the severity of rejection and graft function. Glomerular filtration rate (GFR) at 18 months was significantly better in the patients who were screened and treated for subclinical rejection in comparison to the historical patients (86.7±22.5 vs. 67.9±31.9 ml/min/1.73m2, respectively). The improvement was most remarkable in the youngest (<2 years) age group (94.1±11.0 vs. 67.9±26.8 ml/min/1.73m2). Histological findings of chronic allograft nephropathy were also more common in the historical patients in the 18-month protocol biopsy. All pediatric renal TX patients receive MP as a part of the baseline immunosuppression. Although the maintenance dose of MP is very low in the majority of the patients, the well-known steroid-related adverse affects are not uncommon. It has been shown in a previous study in Finnish pediatric TX patients that steroid exposure, measured as area under concentration-time curve (AUC), rather than the dose correlates with the adverse effects. In the present study, MP AUC was measured in sixteen stable maintenance patients, and a correlation with excess weight gain during 12 months after TX as well as with height deficit was found. A novel bioassay measuring the activation of glucocorticoid receptor dependent transcription cascade was also employed to assess the biological effect of MP. Glucocorticoid bioactivity was found to be related to the adverse effects, although the relationship was not as apparent as that with serum MP concentration. The findings in this study support individualized monitoring and adjustment of immunosuppression based on pharmacokinetics, graft function and histology. Pharmacokinetic profiles are helpful in estimating drug exposure and thus identifying the patients who might be at risk for excessive or insufficient immunosuppression. Individualized doses and monitoring of blood concentrations should definitely be employed with CsA, but possibly also with steroids. As an alternative to complete steroid withdrawal, individualized dosing based on drug exposure monitoring might help in avoiding the adverse effects. Early screening and treatment of subclinical immunoactivation is beneficial as it improves the prospects of good long-term graft function.

Detection of renal dysfunction during and after anaesthesia and surgery - evaluation of the influence of inorganic fluoride, ketorolac and clonidine

Drugs and surgical techniques may have harmful renal effects during the perioperative period. Traditional biomarkers are often insensitive to minor renal changes, but novel biomarkers may more accurately detect disturbances in glomerular and tubular function and integrity. The purpose of this study was first, to evaluate the renal effects of ketorolac and clonidine during inhalation anesthesia with sevoflurane and isoflurane, and secondly, to evaluate the effect of tobacco smoking on the production of inorganic fluoride (F-) following enflurane and sevoflurane anesthesia as well as to determine the effect of F- on renal function and cellular integrity in surgical patients. A total of 143 patients undergoing either conventional (n = 75) or endoscopic (n = 68) inpatient surgery were enrolled in four studies. The ketorolac and clonidine studies were prospective, randomized, placebo controlled and double-blinded, while the cigarette smoking studies were prospective cohort studies with two parallel groups. As a sign of proximal tubular deterioration, a similar transient increase in urine N-acetyl-beta-D-glucosaminidase/creatinine (U-NAG/crea) was noted in both the ketorolac group and in the controls (baseline vs. at two hours of anesthesia, p = 0.015) with a 3.3 minimum alveolar concentration hour sevoflurane anesthesia. Uncorrelated U-NAG increased above the maximum concentration measured from healthy volunteers (6.1 units/l) in 5/15 patients with ketorolac and in none of the controls (p = 0.042). As a sign of proximal tubular deterioration, U-glutathione transferase-alpha/crea (U-GST-alpha/crea) increased in both groups at two hours after anesthesia but a more significant increase was noted in the patients with ketorolac. U-GST-alpha/crea increased above the maximum ratio measured from healthy volunteers in 7/15 patients with ketorolac and in 3/15 controls. Clonidine diminished the activation of the renin-angiotensin aldosterone system during pneumoperitoneum; urine output was better preserved in the patients treated with clonidine (1/15 patients developed oliguria) than in the controls (8/15 developed oliguria (p=0.005)). Most patients with pneumoperitoneum and isoflurane anesthesia developed a transient proximal tubular deterioration, as U-NAG increased above 6.1 units/L in 11/15 patients with clonidine and in 7/15 controls. In the patients receiving clonidine treatment, the median of U-NAG/crea was higher than in the controls at 60 minutes of pneumoperitoneum (p = 0.01), suggesting that clonidine seems to worsen proximal tubular deterioration. Smoking induced the metabolism of enflurane, but the renal function remained intact in both the smokers and the non-smokers with enflurane anesthesia. On the contrary, smoking did not induce sevoflurane metabolism, but glomerular function decreased in 4/25 non-smokers and in 7/25 smokers with sevoflurane anesthesia. All five patients with S-F- ≥ 40 micromol/L, but only 6/45 with S-F- less than 40 micromol/L (p = 0.001), developed a S-tumor associated trypsin inhibitor concentration above 3 nmol/L as a sign of glomerular dysfunction. As a sign of proximal tubulus deterioration, U-beta 2-microglobulin increased in 2/5 patients with S-F- over 40 micromol/L compared to 2/45 patients with the highest S-F- less than 40 micromol/L (p = 0.005). To conclude, sevoflurane anesthesia may cause a transient proximal tubular deterioration which may be worsened by a co-administration of ketorolac. Clonidine premedication prevents the activation of the renin-angiotensin aldosterone system and preserves normal urine output, but may be harmful for proximal tubules during pneumoperitoneum. Smoking induces the metabolism of enflurane but not that of sevoflurane. Serum F- of 40 micromol/L or higher may induce glomerular dysfunction and proximal tubulus deterioration in patients with sevoflurane anesthesia. The novel renal biomarkers warrant further studies in order to establish reference values for surgical patients having inhalation anesthesia.

Molecular Genetics of Age-related Macular Degeneration

Age-related macular degeneration (AMD; OMIM # 603075) is an eye disease of the elderly, signs of which appear after the age of 50. In the Western world it is a leading cause of permanent visual loss with a prevalence of 8.5% in persons under 54 years of age and of 37% in persons over 75 years of age. Early forms of AMD may be asymptomatic, but in the late forms usually a central scotoma in the visual field follows severely complicating daily tasks. Smoking, age, and genetic predisposition are known risk factors for AMD. Until recently no true susceptibility genes had been identified though the composition of drusen deposits, the hallmarks of AMD, has suggested that the complement system might play a role in the pathogenesis of AMD. When four groups reported in March 2005, that, on chromosome 1q32, a Y402H variant in the complement factor H (CFH) gene confers risk for AMD in independent Caucasian samples, a new period in the field of genetic research of AMD started. CFH is a key regulator of the complement system. Thus, it is logical to speculate, that it plays a role in the pathogenesis of AMD. We performed a case-control association study to analyse whether the CFH Y402H variant contain a risk for AMD in the Finnish population. Although the population of Finland represents a genetic isolate, the CFH Y402H polymorphism was associated with AMD also in our patient sample with similar risk allele frequencies as in the other Caucasian populations. We further evaluated the effects of this variant, but no association between lesion subtype (predominantly classic, minimally classic or occult lesion) or lesion size of neovascular AMD and the CFH Y402H variant was detected. Neither did the variant have an effect on the photodynamic therapy (PDT) outcome. The patients that respond to PDT carried the risk genotype as frequently as those who did not respond, and no difference was found in the number of PDT sessions needed in patients with or without the risk genotypes of CFH Y402H. Functional analyses, however, showed that the binding of C-reactive protein (CRP) to CFH was significantly reduced in patients with the risk genotype of Y402H. In the past two years, the LOC387715/ high-temperature requirement factor A1 (HTRA1) locus on 10q26 has also been repeatedly associated with AMD in several populations. The recent discovery of the LOC387715 protein on the mitochondrial outer membrane suggests that the LOC387715 gene, not HTRA1, is the true predisposing gene in this region, although its biological function is still unknown. In our Finnish patient material, patients with AMD carried the A69S risk genotype of LOC387715 more frequently than the controls. Also, for the first time, an interaction between the CFH Y402H and the LOC387715 A69S variants was found. The most recently detected susceptibilty gene of AMD, the complement component 3 (C3) gene, encodes the central component of the complement system, C3. In our Finnish sample, an additive gene effect for the C3 locus was detected, though weaker than the effects for the two main loci, CFH and LOC387715. Instead, the hemicentin-1 or the elongation of very long chain fatty acids-like 4 genes that have also been suggested as candidate genes for AMD did not carry a risk for AMD in the Finnish population. This was the first series of molecular genetic study of AMD in Finland. We showed that two common risk variants, CFH Y402H and LOC387715 A69S, represent a high risk of AMD also in the isolated Finnish population, and furthermore, that they had a statistical interaction. It was demonstrated that the CFH Y402H risk genotype affects the binding of CFH to CRP thus suggesting that complement indeed plays an important role in the pathogenesis of AMD.

Complement factor C4 and immunoglobulins in recurrent or chronic mucosal infections

The study assessed whether plasma concentrations of complement factors C3, C4, or immunoglobulins, serum classical pathway hemolytyic activity, or polymorphisms in the class I and II HLA genes, isotypes and gene numbers of C4, or allotypes of IgG1 and IgG3 heavy chain genes were associated with severe frequently recurring or chronic mucosal infections. According to strict clinical criteria, 188 consecutive voluntary patients without a known immunodeficiency and 198 control subjects were recruited. Frequencies of low levels in IgG1, IgG2, IgG3 and IgG4 were for the first time tested from adult general population and patients with acute rhinosinusitis. Frequently recurring intraoral herpes simplex type 1 infections, a rare form of the disease, was associated with homozygosity in HLA -A*, -B*, -C*, and -DR* genes. Frequently recurrent genital HSV-2 infections were associated with low levels of IgG1 and IgG3, present in 54% of the recruited patients. This association was partly allotype-dependent. The G3mg,G1ma/ax haplotype, together with low IgG3, was more common in patients than in control subjects who lacked antibodies against herpes simplex viruses. This is the first found immunogenetic deficiency in otherwise healthy adults that predisposes to highly frequent mucosal herpes recurrences. According to previous studies, HSV effectively evades the allotype G1ma/ax of IgG1, whereas G3mg is associated with low IgG3. Certain HLA genes were more common in patients than in control subjects. Having more than one C4A or C4B gene was associated with neuralgias caused by the virus. Low levels of IgA, IgG1, IgG2, IgG3, and IgG4 were common in the general adult population, but even more frequent in patients with chronic sinusitis. Only low IgG1 was more common chronic than in acute rhinosinusitis. Clinically, nasal polyposis and bronchial asthma were associated with complicated disease forms. The best differentiating immunologic parameters were C4A deficiency and the combination of low plasma IgG4 together with low IgG1 or IgG2, performing almost equally. The lack of C4A, IgA, and IgG4, all known to possess anti-inflammatory activity, together with a concurrently impaired immunity caused by low subclass levels, may predispose to chronic disease forms. In severe chronic adult periodontitis, any C4A or C4B deficiency combined was associated with the disease. The new quantitative analysis of C4 genes and the conventional C4 allotyping method complemented each other. Lowered levels of plasma C3 or C4 or both, and serum CH50 were found in herpes and periodontitis patients. In rhinosinusitis, there was a linear trend with the highest levels found in the order: acute > chronic rhinosinusitis > general population > blood donors with no self-reported history of rhinosinusitis. Complement is involved in the defense against the tested mucosal infections. Seemingly immunocompetent patients with chronic or recurrent mucosal infections frequently have subtle weaknesses in different arms of immunity. Their susceptibility to chronic disease forms may be caused by these. Host s subtly impaired immunity often coincides with effective immune evasion from the same arms of immunity by the disease-causing pathogens. The interpretation of low subclass levels, if no additional predisposing immunologic factors are tested, is difficult and of limited value in early diagnosis and treatment.

Childhood otitis media - risk factors and surgical management

Background: Otitis media (OM) is one of the most common childhood diseases. Approximately every third child suffers from recurrent acute otitis media (RAOM), and 5% of all children have persistent middle ear effusion for months during their childhood. Despite numerous studies on the prevention and treatment of OM during the past decades, its management remains challenging and controversial. In this study, the effect of adenoidectomy on the risk for OM, the potential risk factors influencing the development of OM and the frequency of asthma among otitis-prone children were investigated. Subjects and methods: One prospective randomized trial and two retrospective studies were conducted. In the prospective trial, 217 children with RAOM or chronic otitis media with effusion (COME) were randomized to have tympanostomy with or without adenoidectomy. The age of the children at recruitment was between 1 and 4 years. RAOM was defined as having at least 3 episodes of AOM during the last 6 months or at least 5 episodes of AOM during the last 12 months. COME was defined as having persistent middle ear effusion for 2-3 months. The children were followed up for one year. In the first retrospective study, the frequency of childhood infections and allergy was evaluated by a questionnaire among 819 individuals. In the second retrospective study, data of asthma diagnosis were analysed from hospital discharge records of 1616 children who underwent adenoidectomy or had probing of the nasolacrimal duct. Results: In the prospective randomized study, adenoidectomy had no beneficial effect on the prevention of subsequent episodes of AOM. Parental smoking was found to be a significant risk factor for OM even after the insertion of tympanostomy tubes. The frequencies of exposure to tobacco smoke and day-care attendance at the time of randomization were similar among children with RAOM and COME. However, the frequencies of allergy to animal dust and pollen and parental asthma were lower among children with COME than those with RAOM. The questionnaire survey and the hospital discharge data revealed that children who had frequent episodes of OM had an increased risk for asthma. Conclusions: The first surgical intervention to treat an otitis-prone child younger than 4 years should not include adenoidectomy. Interventions to stop parental smoking could significantly reduce the risk for childhood RAOM. Whether an otitis-prone child develops COME or RAOM, seems to be influenced by genetic predisposition more strongly than by environmental risk factors. Children who suffer from repeated upper respiratory tract infections, like OM, may be at increased risk for developing asthma.

Cyclosporine population pharmacokinetics in pediatric renal transplant recipients

Cyclosporine is an immunosuppressant drug with a narrow therapeutic index and large variability in pharmacokinetics. To improve cyclosporine dose individualization in children, we used population pharmacokinetic modeling to study the effects of developmental, clinical, and genetic factors on cyclosporine pharmacokinetics in altogether 176 subjects (age range: 0.36–20.2 years) before and up to 16 years after renal transplantation. Pre-transplantation test doses of cyclosporine were given intravenously (3 mg/kg) and orally (10 mg/kg), on separate occasions, followed by blood sampling for 24 hours (n=175). After transplantation, in a total of 137 patients, cyclosporine concentration was quantified at trough, two hours post-dose, or with dose-interval curves. One-hundred-four of the studied patients were genotyped for 17 putatively functionally significant sequence variations in the ABCB1, SLCO1B1, ABCC2, CYP3A4, CYP3A5, and NR1I2 genes. Pharmacokinetic modeling was performed with the nonlinear mixed effects modeling computer program, NONMEM. A 3-compartment population pharmacokinetic model with first order absorption without lag-time was used to describe the data. The most important covariate affecting systemic clearance and distribution volume was allometrically scaled body weight i.e. body weight**3/4 for clearance and absolute body weight for volume of distribution. The clearance adjusted by absolute body weight declined with age and pre-pubertal children (< 8 years) had an approximately 25% higher clearance/body weight (L/h/kg) than did older children. Adjustment of clearance for allometric body weight removed its relationship to age after the first year of life. This finding is consistent with a gradual reduction in relative liver size towards adult values, and a relatively constant CYP3A content in the liver from about 6–12 months of age to adulthood. The other significant covariates affecting cyclosporine clearance and volume of distribution were hematocrit, plasma cholesterol, and serum creatinine, explaining up to 20%–30% of inter-individual differences before transplantation. After transplantation, their predictive role was smaller, as the variations in hematocrit, plasma cholesterol, and serum creatinine were also smaller. Before transplantation, no clinical or demographic covariates were found to affect oral bioavailability, and no systematic age-related changes in oral bioavailability were observed. After transplantation, older children receiving cyclosporine twice daily as the gelatine capsule microemulsion formulation had an about 1.25–1.3 times higher bioavailability than did the younger children receiving the liquid microemulsion formulation thrice daily. Moreover, cyclosporine oral bioavailability increased over 1.5-fold in the first month after transplantation, returning thereafter gradually to its initial value in 1–1.5 years. The largest cyclosporine doses were administered in the first 3–6 months after transplantation, and thereafter the single doses of cyclosporine were often smaller than 3 mg/kg. Thus, the results suggest that cyclosporine displays dose-dependent, saturable pre-systemic metabolism even at low single doses, whereas complete saturation of CYP3A4 and MDR1 (P-glycoprotein) renders cyclosporine pharmacokinetics dose-linear at higher doses. No significant associations were found between genetic polymorphisms and cyclosporine pharmacokinetics before transplantation in the whole population for which genetic data was available (n=104). However, in children older than eight years (n=22), heterozygous and homozygous carriers of the ABCB1 c.2677T or c.1236T alleles had an about 1.3 times or 1.6 times higher oral bioavailability, respectively, than did non-carriers. After transplantation, none of the ABCB1 SNPs or any other SNPs were found to be associated with cyclosporine clearance or oral bioavailability in the whole population, in the patients older than eight years, or in the patients younger than eight years. In the whole population, in those patients carrying the NR1I2 g.-25385C–g.-24381A–g.-205_-200GAGAAG–g.7635G–g.8055C haplotype, however, the bioavailability of cyclosporine was about one tenth lower, per allele, than in non-carriers. This effect was significant also in a subgroup of patients older than eight years. Furthermore, in patients carrying the NR1I2 g.-25385C–g.-24381A–g.-205_-200GAGAAG–g.7635G–g.8055T haplotype, the bioavailability was almost one fifth higher, per allele, than in non-carriers. It may be possible to improve individualization of cyclosporine dosing in children by accounting for the effects of developmental factors (body weight, liver size), time after transplantation, and cyclosporine dosing frequency/formulation. Further studies are required on the predictive value of genotyping for individualization of cyclosporine dosing in children.

Lung structure and function studied by synchrotron radiation

A novel method for functional lung imaging was introduced by adapting the K-edge subtraction method (KES) to in vivo studies of small animals. In this method two synchrotron radiation energies, which bracket the K-edge of the contrast agent, are used for simultaneous recording of absorption-contrast images. Stable xenon gas is used as the contrast agent, and imaging is performed in projection or computed tomography (CT) mode. Subtraction of the two images yields the distribution of xenon, while removing practically all features due to other structures, and the xenon density can be calculated quantitatively. Because the images are recorded simultaneously, there are no movement artifacts in the subtraction image. Time resolution for a series of CT images is one image/s, which allows functional studies. Voxel size is 0.1mm3, which is an order better than in traditional lung imaging methods. KES imaging technique was used in studies of ventilation distribution and the effects of histamine-induced airway narrowing in healthy, mechanically ventilated, and anaesthetized rabbits. First, the effect of tidal volume on ventilation was studied, and the results show that an increase in tidal volume without an increase in minute ventilation results a proportional increase in regional ventilation. Second, spiral CT was used to quantify the airspace volumes in lungs in normal conditions and after histamine aerosol inhalation, and the results showed large patchy filling defects in peripheral lungs following histamine provocation. Third, the kinetics of proximal and distal airway response to histamine aerosol were examined, and the findings show that the distal airways react immediately to histamine and start to recover, while the reaction and the recovery in proximal airways is slower. Fourth, the fractal dimensions of lungs was studied, and it was found that the fractal dimension is higher at the apical part of the lungs compared to the basal part, indicating structural differences between apical and basal lung level. These results provide new insights to lung function and the effects of drug challenge studies. Nowadays the technique is available at synchrotron radiation facilities, but the compact synchrotron radiation sources are being developed, and in relatively near future the method may be used at hospitals.

Tuloverotuksen reaalinen muuttuminen Suomessa : Kuusikymmentä vuotta verojen vuoristorataa

The study seeks to find out whether the real burden of the personal taxation has increased or decreased. In order to determine this, we investigate how the same real income has been taxed in different years. Whenever the taxes for the same real income for a given year are higher than for the base year, the real tax burden has increased. If they are lower, the real tax burden has decreased. The study thus seeks to estimate how changes in the tax regulations affect the real tax burden. It should be kept in mind that the progression in the central government income tax schedule ensures that a real change in income will bring about a change in the tax ration. In case of inflation when the tax schedules are kept nominally the same will also increase the real tax burden. In calculations of the study it is assumed that the real income remains constant, so that we can get an unbiased measure of the effects of governmental actions in real terms. The main factors influencing the amount of income taxes an individual must pay are as follows: - Gross income (income subject to central and local government taxes). - Deductions from gross income and taxes calculated according to tax schedules. - The central government income tax schedule (progressive income taxation). - The rates for the local taxes and for social security payments (proportional taxation). In the study we investigate how much a certain group of taxpayers would have paid in taxes according to the actual tax regulations prevailing indifferent years if the income were kept constant in real terms. Other factors affecting tax liability are kept strictly unchanged (as constants). The resulting taxes, expressed in fixed prices, are then compared to the taxes levied in the base year (hypothetical taxation). The question we are addressing is thus how much taxes a certain group of taxpayers with the same socioeconomic characteristics would have paid on the same real income according to the actual tax regulations prevailing in different years. This has been suggested as the main way to measure real changes in taxation, although there are several alternative measures with essentially the same aim. Next an aggregate indicator of changes in income tax rates is constructed. It is designed to show how much the taxation of income has increased or reduced from one year to next year on average. The main question remains: How aggregation over all income levels should be performed? In order to determine the average real changes in the tax scales the difference functions (difference between actual and hypothetical taxation functions) were aggregated using taxable income as weights. Besides the difference functions, the relative changes in real taxes can be used as indicators of change. In this case the ratio between the taxes computed according to the new and the old situation indicates whether the taxation has become heavier or easier. The relative changes in tax scales can be described in a way similar to that used in describing the cost of living, or by means of price indices. For example, we can use Laspeyres´ price index formula for computing the ratio between taxes determined by the new tax scales and the old tax scales. The formula answers the question: How much more or less will be paid in taxes according to the new tax scales than according to the old ones when the real income situation corresponds to the old situation. In real terms the central government tax burden experienced a steady decline from its high post-war level up until the mid-1950s. The real tax burden then drifted upwards until the mid-1970s. The real level of taxation in 1975 was twice that of 1961. In the 1980s there was a steady phase due to the inflation corrections of tax schedules. In 1989 the tax schedule fell drastically and from the mid-1990s tax schedules have decreased the real tax burden significantly. Local tax rates have risen continuously from 10 percent in 1948 to nearly 19 percent in 2008. Deductions have lowered the real tax burden especially in recent years. Aggregate figures indicate how the tax ratio for the same real income has changed over the years according to the prevailing tax regulations. We call the tax ratio calculated in this manner the real income tax ratio. A change in the real income tax ratio depicts an increase or decrease in the real tax burden. The real income tax ratio declined after the war for some years. In the beginning of the 1960s it nearly doubled to mid-1970. From mid-1990s the real income tax ratio has fallen about 35 %.

Very Low Birth Weight Infants as Young Adults : Focus on aspects of cognition, behavior and sleep

Major advances in the treatment of preterm infants have occurred during the last three decades. Survival rates have increased, and the first generations of preterm infants born at very low birth weight (VLBW; less than 1500 g) who profited from modern neonatal intensive care are now in young adulthood. The literature shows that VLBW children achieve on average lower scores on cognitive tests, even after exclusion of individuals with obvious neurosensory deficits. Evidence also exists for an increased risk in VLBW children for various neuropsychiatric disorders such as attention-deficit hyperactivity disorder (ADHD) and related behavioral symptoms. Up till now, studies extending into adulthood are sparse, and it remains to be seen whether these problems persist into adulthood. The aim of this thesis was to study ADHD-related symptoms and cognitive and executive functioning in young adults born at VLBW. In addition, we aimed to study sleep disturbances, known to adversely affect both cognition and attention. We hypothesized that preterm birth at VLBW interferes with early brain development in a way that alters the neuropsychological phenotype; this may manifest itself as ADHD symptoms and impaired cognitive abilities in young adulthood. In this cohort study from a geographically defined region, we studied 166 VLBW adults and 172 term-born controls born from 1978 through 1985. At ages 18 to 27 years, the study participants took part in a clinic study during which their physical and psychological health was assessed in detail. Three years later, 213 of these individuals participated in a follow-up. The current study is part of a larger research project (The Helsinki Study of Very Low Birth Weight Adults), and the measurements of interest for this particular study include the following: 1) The Adult Problem Questionnaire (APQ), a self-rating scale of ADHD-related symptoms in adults; 2) A computerized cognitive test battery designed for population studies (CogState®) which measures core cognitive abilities such as reaction time, working memory, and visual learning; 3) Sleep assessment by actigraphy, the Basic Nordic Sleep Questionnaire, and the Morningness-Eveningness Questionnaire. Actigraphs are wrist-worn accelerometers that separate sleep from wakefulness by registering body movements. Contrary to expectations, VLBW adults as a group reported no more ADHD-related behavioral symptoms than did controls. Further subdivision of the VLBW group into SGA (small for gestational age) and AGA (appropriate for gestational age) subgroups, however, revealed more symptoms on ADHD subscales pertaining to executive dysfunction and emotional instability among those born SGA. Thus, it seems that intrauterine growth retardation (for which SGA served as a proxy) is a more essential predictor for self-perceived ADHD symptoms in adulthood than is VLBW birth as such. In line with observations from other cohorts, the VLBW adults reported less risk-taking behavior in terms of substance use (alcohol, smoking, and recreational drugs), a finding reassuring for the VLBW individuals and their families. On the cognitive test, VLBW adults free from neurosensory deficits had longer reaction times than did term-born peers on all tasks included in the test battery, and lower accuracy on the learning task, with no discernible effect of SGA status over and above the effect of VLBW. Altogether, on a group level, even high-functioning VLBW adults show subtle deficits in psychomotor processing speed, visual working memory, and learning abilities. The sleep studies provided no evidence for differences in sleep quality or duration between the two groups. The VLBW adults were, however, at more than two-fold higher risk for sleep-disordered breathing (in terms of chronic snoring). Given the link between sleep-disordered breathing and health sequelae, these results suggest that VLBW individuals may benefit from an increased awareness among clinicians of this potential problem area. An unexpected finding from the sleep studies was the suggestion of an advanced sleep phase: The VLBW adults went to bed earlier according to the actigraphy registrations and also reported earlier wake-up times on the questionnaire. In further study of this issue in conjunction with the follow-up three years later, the VLBW group reported higher levels of morningness propensity, further corroborating the preliminary findings of an advanced sleep phase. Although the clinical implications are not entirely clear, the issue may be worth further study, since circadian rhythms are closely related to health and well-being. In sum, we believe that increased understanding of long-term outcomes after VLBW, and identification of areas and subgroups that are particularly vulnerable, will allow earlier recognition of potential problems and ultimately lead to improved prevention strategies.

Essays on Market Microstructure: Price Discovery and Informed Trading

Market microstructure is “the study of the trading mechanisms used for financial securities” (Hasbrouck (2007)). It seeks to understand the sources of value and reasons for trade, in a setting with different types of traders, and different private and public information sets. The actual mechanisms of trade are a continually changing object of study. These include continuous markets, auctions, limit order books, dealer markets, or combinations of these operating as a hybrid market. Microstructure also has to allow for the possibility of multiple prices. At any given time an investor may be faced with a multitude of different prices, depending on whether he or she is buying or selling, the quantity he or she wishes to trade, and the required speed for the trade. The price may also depend on the relationship that the trader has with potential counterparties. In this research, I touch upon all of the above issues. I do this by studying three specific areas, all of which have both practical and policy implications. First, I study the role of information in trading and pricing securities in markets with a heterogeneous population of traders, some of whom are informed and some not, and who trade for different private or public reasons. Second, I study the price discovery of stocks in a setting where they are simultaneously traded in more than one market. Third, I make a contribution to the ongoing discussion about market design, i.e. the question of which trading systems and ways of organizing trading are most efficient. A common characteristic throughout my thesis is the use of high frequency datasets, i.e. tick data. These datasets include all trades and quotes in a given security, rather than just the daily closing prices, as in traditional asset pricing literature. This thesis consists of four separate essays. In the first essay I study price discovery for European companies cross-listed in the United States. I also study explanatory variables for differences in price discovery. In my second essay I contribute to earlier research on two issues of broad interest in market microstructure: market transparency and informed trading. I examine the effects of a change to an anonymous market at the OMX Helsinki Stock Exchange. I broaden my focus slightly in the third essay, to include releases of macroeconomic data in the United States. I analyze the effect of these releases on European cross-listed stocks. The fourth and last essay examines the uses of standard methodologies of price discovery analysis in a novel way. Specifically, I study price discovery within one market, between local and foreign traders.

Molecular background of three lethal fetal syndromes

This study identified the molecular defects underlying three lethal fetal syndromes. Lethal Congenital Contracture Syndrome 1 (LCCS1, MIM 253310) and Lethal Arthrogryposis with Anterior Horn Cell Disease (LAAHD, MIM 611890) are fetal motor neuron diseases. They affect the nerve cells that control voluntary muscle movement, and eventually result in severe atrophy of spinal cord motor neurons and fetal immobility. Both LCCS1 and LAAHD are caused by mutations in the GLE1 gene, which encodes for a multifunctional protein involved in posttranscriptional mRNA processing. LCCS2 and LCCS3, two syndromes that are clinically similar to LCCS1, are caused by defective proteins involved in the synthesis of inositol hexakisphosphate (IP6), an essential cofactor of GLE1. This suggests a common mechanism behind these fetal motor neuron diseases, and along with accumulating evidence from genetic studies of more late-onset motor neuron diseases such as Spinal muscular atrophy (SMA) and Amyotrophic lateral sclerosis (ALS), implicates mRNA processing as a common mechanism in motor neuron disease pathogenesis. We also studied gle1-/- zebrafish in order to investigate whether they would be a good model for studying the pathogenesis of LCCS1 and LAAHD. Mutant zebrafish exhibit cell death in their central nervous system at two days post fertilization, and the distribution of mRNA within the cells of mutant zebrafish differs from controls, encouraging further studies. The third lethal fetal syndrome is described in this study for the first time. Cocoon syndrome (MIM 613630) was discovered in a Finnish family with two affected individuals. Its hallmarks are the encasement of the limbs under the skin, and severe craniofacial abnormalities, including the lack of skull bones. We showed that Cocoon syndrome is caused by a mutation in the gene encoding the conserved helix-loop-helix ubiquitous kinase CHUK, also known as IκB kinase α (IKKα). The mutation results in the complete lack of CHUK protein expression. CHUK is a subunit of the IκB kinase enzyme that inhibits NF-κB transcription factors, but in addition, it has an essential, independent role in controlling keratinocyte differentiation, as well as informing morphogenetic events such as limb and skeletal patterning. CHUK also acts as a tumor suppressor, and is frequently inactivated in cancer. This study has brought significant new information about the molecular background of these three lethal fetal syndromes, as well as provided knowledge about the prerequisites of normal human development.

"Miksi lehmät pitää tappaa?" : Etnografinen tutkimus 2000-luvun alun huumemarkkinoista Helsingissä

The present study focuses on the drug market in Helsinki in the early 2000s, mainly on the dealing in and use of amphetamines, cannabis and the pharmaceutical Subutex. The drug market is usually analysed into upper, middle and lower level markets. These levels are very different in terms of their operating practices, although there may be some mingling. The present study is mainly concerned with drug dealers and users in the lower and middle level markets. Operations also differ depending on whether the dealing involves just one drug or several. Dealing in and using Subutex is a very different business from dealing and using home grown cannabis, for instance: both the customers and the dealers are mostly quite different. The study material was mostly collected through ethnographical field work, including observations and interviews. Interviews with officials and minutes of pre-trial investigations concerning aggravated drug crimes are also included. The study discusses the roles of dealers on the various levels of the drug market in Helsinki and traces activities at various levels. Ethnographical methods are employed to observe day-to-day drug dealing and use and leisure pursuits in private homes and in public premises. The study takes note of the risks inherent in drug dealing and estimates what kind of drug dealers can last the longest on the market without the authorities intervening. At the same time, the study discusses how small groups on the middle and lower levels of the drug market avoid control measures undertaken by the authorities and how the authorities address these groups. Moreover, the study discusses what the drug market is like in prison from the perspective of a drug dealer sent to prison, what their everyday lives are like after release, and how much money dealers on various levels of the drug market make. The study demonstrates that drug dealing in Helsinki, whether we consider the very top or the very bottom of the pyramid, is a far from rational pursuit. The undertakings are not very systematic; they are more a reaction to intoxicant addiction( s) and other problems caused by other dealers, the dealers own actions and the actions of the police. The everyday lives of drug dealers are often chaos only alleviated by drug use in the company of buyers or alone. If a drug dealer uses drugs himself/herself, things become even more complicated and a vicious circle develops. At the same time, everyday life is certainly exciting, and a drug dealer often has a highly eventful if brief life. Drug dealing is a very masculine pursuit, and there is a sort of macho code governing it, although this does not nearly always work as it should. This macho code, typically for illegal activities, involves the threat of violence as a control measure. Hence the untranslatable slang expression Kill the cows : the Finnish word for calf has the slang meaning snitch or police informant . No more cows, no more calves. But informing on others to the authorities is a fact of life in the drug-dealing world. Contributing factors to being reported to the authorities are the dealer s own mistakes and the actions of other dealers and the police. A determined drug dealer will not be deterred from drug dealing by a prison sentence. However, following time in prison only few dealers manage to gain an income from drug dealing commensurate with its risks.

Kädestä suuhun : Makro- ja mikrotaloudellinen tarkastelu suomalaisten kotitalouksien säästämisestä ja sen mittaamisesta 1950-luvulla

This study is divided into two parts: a methodological part and a part which focuses on the saving of households. In the 1950 s both the concepts as well as the household surveys themselves went through a rapid change. The development of national accounts was motivated by the Keynesian theory and the 1940 s and 1950 s were an important time for the development of the national accounts. Before this, saving was understood as cash money or money deposited in bank accounts but the changes in this era led to the establishment of the modern saving concept. Separate from the development of national accounts, household surveys were established. Household surveys have been conducted in Finland from the beginning of the 20th century. At that time surveys were conducted in order to observe the working class living standard and as a result, these were based on the tradition of welfare studies. Also a motivation for undertaking the studies was to estimate weights for the consumer price index. A final reason underpinning the government s interest in observing this data regarded whether there were any reasons for the working class to become radicalised and therefore adopt revolutionary ideas. As the need for the economic analysis increased and the data requirements underlying the political decision making process also expanded, the two traditions and thus, the two data sources started to integrate. In the 1950s the household surveys were compiled distinctly from the national accounts and they were virtually unaffected by economic theory. The 1966 survey was the first study that was clearly motivated by national accounts and saving analysis. This study also covered the whole population rather than it being limited to just part of it. It is essential to note that the integration of these two traditions is still continuing. This recently took a big step forward as the Stiglitz, Sen and Fitoussi Committee Report was introduced and thus, the criticism of the current measure of welfare was taken seriously. The Stiglitz report emphasises that the focus in the measurement of welfare should be on the households and the macro as well as micro perspective should be included in the analysis. In this study the national accounts are applied to the household survey data from the years 1950-51, 1955-56 and 1959-60. The first two studies cover the working population of towns and market towns and the last survey covers the population of rural areas. The analysis is performed at three levels: macro economic level, meso level, i.e. at the level of different types of households, and micro level, i.e. at the level of individual households. As a result it analyses how the different households saved and consumed and how that changed during the 1950 s.

Preterm birth and risk factors for chronic disease : Helsinki Study of Very Low Birth Weight Adults

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.

Preterm birth and risk factors for chronic disease : Helsinki Study of Very Low Birth Weight Adults

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.