Predicting body weight from body measurements of pre-pubertal Ayshire heifers

Selostus: Hiehojen elopainon määrittäminen mittauksin alkukasvatusvaiheessa

Home Blood Pressure Measurement – Epidemiology and Clinical Application

Verenpaineen kotimittaus − epidemiologia ja kliininen käyttö Kohonnutta verenpainetta, maailmanlaajuisesti merkittävintä ennenaikaiselle kuolemalle altistavaa riskitekijää, ei voida tunnistaa tai hoitaa ilman tarkkoja ja käytännöllisiä verenpaineen mittausmenetelmiä. Verenpaineen kotimittaus on saavuttanut suuren suosion potilaiden keskuudessa. Lääkärit eivät ole kuitenkaan vielä täysin hyväksyneet verenpaineen kotimittausta, sillä riittävä todistusaineisto sen toimivuudesta ja eduista on puuttunut. Tämän tutkimuksen tarkoituksena oli osoittaa, että kotona mitattu verenpaine (kotipaine) on perinteistä vastaanotolla mitattua verenpainetta (vastaanottopaine) tarkempi, ja että se on tehokas myös kliinisessä käytössä. Tutkimme kotipaineen käyttöä verenpainetaudin diagnosoinnissa ja hoidossa. Lisäksi tarkastelimme kotipaineen yhteyttä verenpainetaudin aiheuttamiin kohde-elinvaurioihin. Ensimmäinen aineisto, joka oli edustava otos Suomen aikuisväestöstä, koostui 2 120 45–74-vuotiaasta tutkimushenkilöstä. Tutkittavat mittasivat kotipainettaan viikon ajan ja osallistuivat terveystarkastukseen, johon sisältyi kliinisen tutkimuksen ja haastattelun lisäksi sydänfilmin otto ja vastaanottopaineen mittaus. 758 tutkittavalle suoritettiin lisäksi kaulavaltimon seinämän intima-mediakerroksen paksuuden (valtimonkovettumataudin mittari) mittaus ja 237:lle valtimon pulssiaallon nopeuden (valtimojäykkyyden mittari) mittaus. Toisessa aineistossa, joka koostui 98 verenpainetautia sairastavasta potilaasta, hoitoa ohjattiin satunnaistamisesta riippuen joko ambulatorisen eli vuorokausirekisteröinnillä mitatun verenpaineen tai kotipaineen perusteella. Vastaanottopaine oli kotipainetta merkittävästi korkeampi (systolisen/diastolisen paineen keskiarvoero oli 8/3 mmHg) ja yksimielisyys verenpainetaudin diagnoosissa kahden menetelmän välillä oli korkeintaan kohtalainen (75 %). 593 tutkittavasta, joilla oli kohonnut verenpaine vastaanotolla, 38 %:lla oli normaali verenpaine kotona eli ns. valkotakkiverenpaine. Verenpainetauti voidaan siis ylidiagnosoida joka kolmannella potilaalla seulontatilanteessa. Valkotakkiverenpaine oli yhteydessä lievästi kohonneeseen verenpaineeseen, matalaan painoindeksiin ja tupakoimattomuuteen, muttei psykiatriseen sairastavuuteen. Valkotakkiverenpaine ei kuitenkaan vaikuttaisi olevan täysin vaaraton ilmiö ja voi ennustaa tulevaa verenpainetautia, sillä siitä kärsivien sydän- ja verisuonitautien riskitekijäprofiili oli normaalipaineisten ja todellisten verenpainetautisten riskitekijäprofiilien välissä. Kotipaineella oli vastaanottopainetta vahvempi yhteys verenpainetaudin aiheuttamiin kohde-elinvaurioihin (intima-mediakerroksen paksuus, pulssiaallon nopeus ja sydänfilmistä todettu vasemman kammion suureneminen). Kotipaine oli tehokas verenpainetaudin hoidon ohjaaja, sillä kotipaineeseen ja ambulatoriseen paineeseen, jota on pidetty verenpainemittauksen ”kultaisena standardina”, perustuva lääkehoidon ohjaus johti yhtä hyvään verenpaineen hallintaan. Tämän ja aikaisempien tutkimusten tulosten pohjalta voidaan todeta, että verenpaineen kotimittaus on selkeä parannus perinteiseen vastaanotolla tapahtuvaan verenpainemittaukseen verrattuna. Verenpaineen kotimittaus on käytännöllinen, tarkka ja laajasti saatavilla oleva menetelmä, josta voi tulla jopa ensisijainen vaihtoehto verenpainetautia diagnosoitaessa ja hoitaessa. Verenpaineen mittauskäytäntöön tarvitaan muutos, sillä näyttöön perustuvan lääketieteen perusteella vaikuttaa, että vastaanotolla tapahtuvaa verenpainemittausta tulisi käyttää vain seulontatarkoitukseen.

Modeling the transport phenomena within arterial wall: porous media approach

The transport of macromolecules, such as low-density lipoprotein (LDL), and their accumulation in the layers of the arterial wall play a critical role in the creation and development of atherosclerosis. Atherosclerosis is a disease of large arteries e.g., the aorta, coronary, carotid, and other proximal arteries that involves a distinctive accumulation of LDL and other lipid-bearing materials in the arterial wall. Over time, plaque hardens and narrows the arteries. The flow of oxygen-rich blood to organs and other parts of the body is reduced. This can lead to serious problems, including heart attack, stroke, or even death. It has been proven that the accumulation of macromolecules in the arterial wall depends not only on the ease with which materials enter the wall, but also on the hindrance to the passage of materials out of the wall posed by underlying layers. Therefore, attention was drawn to the fact that the wall structure of large arteries is different than other vessels which are disease-resistant. Atherosclerosis tends to be localized in regions of curvature and branching in arteries where fluid shear stress (shear rate) and other fluid mechanical characteristics deviate from their normal spatial and temporal distribution patterns in straight vessels. On the other hand, the smooth muscle cells (SMCs) residing in the media layer of the arterial wall respond to mechanical stimuli, such as shear stress. Shear stress may affect SMC proliferation and migration from the media layer to intima. This occurs in atherosclerosis and intimal hyperplasia. The study of blood flow and other body fluids and of heat transport through the arterial wall is one of the advanced applications of porous media in recent years. The arterial wall may be modeled in both macroscopic (as a continuous porous medium) and microscopic scales (as a heterogeneous porous medium). In the present study, the governing equations of mass, heat and momentum transport have been solved for different species and interstitial fluid within the arterial wall by means of computational fluid dynamics (CFD). Simulation models are based on the finite element (FE) and finite volume (FV) methods. The wall structure has been modeled by assuming the wall layers as porous media with different properties. In order to study the heat transport through human tissues, the simulations have been carried out for a non-homogeneous model of porous media. The tissue is composed of blood vessels, cells, and an interstitium. The interstitium consists of interstitial fluid and extracellular fibers. Numerical simulations are performed in a two-dimensional (2D) model to realize the effect of the shape and configuration of the discrete phase on the convective and conductive features of heat transfer, e.g. the interstitium of biological tissues. On the other hand, the governing equations of momentum and mass transport have been solved in the heterogeneous porous media model of the media layer, which has a major role in the transport and accumulation of solutes across the arterial wall. The transport of Adenosine 5´-triphosphate (ATP) is simulated across the media layer as a benchmark to observe how SMCs affect on the species mass transport. In addition, the transport of interstitial fluid has been simulated while the deformation of the media layer (due to high blood pressure) and its constituents such as SMCs are also involved in the model. In this context, the effect of pressure variation on shear stress is investigated over SMCs induced by the interstitial flow both in 2D and three-dimensional (3D) geometries for the media layer. The influence of hypertension (high pressure) on the transport of lowdensity lipoprotein (LDL) through deformable arterial wall layers is also studied. This is due to the pressure-driven convective flow across the arterial wall. The intima and media layers are assumed as homogeneous porous media. The results of the present study reveal that ATP concentration over the surface of SMCs and within the bulk of the media layer is significantly dependent on the distribution of cells. Moreover, the shear stress magnitude and distribution over the SMC surface are affected by transmural pressure and the deformation of the media layer of the aorta wall. This work reflects the fact that the second or even subsequent layers of SMCs may bear shear stresses of the same order of magnitude as the first layer does if cells are arranged in an arbitrary manner. This study has brought new insights into the simulation of the arterial wall, as the previous simplifications have been ignored. The configurations of SMCs used here with elliptic cross sections of SMCs closely resemble the physiological conditions of cells. Moreover, the deformation of SMCs with high transmural pressure which follows the media layer compaction has been studied for the first time. On the other hand, results demonstrate that LDL concentration through the intima and media layers changes significantly as wall layers compress with transmural pressure. It was also noticed that the fraction of leaky junctions across the endothelial cells and the area fraction of fenestral pores over the internal elastic lamina affect the LDL distribution dramatically through the thoracic aorta wall. The simulation techniques introduced in this work can also trigger new ideas for simulating porous media involved in any biomedical, biomechanical, chemical, and environmental engineering applications.

Clinically occult metastases in patients with cutaneous melanoma. Detection with sentinel lymph node biopsy and whole body positron emission tomography

Objective: The aim of this study was to investigate the use of sentinel lymph node biopsy (SLNB) and whole body positron emission tomography (PET), with emphasis on surgical treatment and prognosis, in the detection of clinically occult metastases in patients with clinically localized cutaneous melanoma. Patients and methods: The study population consisted of 1255 patients with clinical stage I–II cutaneous melanoma, operated at Turku University Hospital between 1983 and 2007. 334 patients underwent SLNB and they were compared to 921 retrospective patients. A subgroup of 30 symptom-free patients with high risk melanoma underwent prospectively whole body PET 6–24 months postoperatively. Results: Overall, the disease-specific survival rate was 84.4 % at five years. Sex, Breslow thickness, age and nodal status were independent prognostic factors for survival. SLNB revealed occult nodal metastases in 17 % of the patients. There was no significant difference in disease-specific overall survival between SLNB patients and controls, but the nodal disease-free time was significantly longer suggesting better local control after SLNB and subsequent completion lymph node dissection. The followup time was different between the study cohorts and initial surgery was performed during different time periods. SLNB detected micrometastases in seven of 155 patients (4.5 %) with thin T1 primary melanoma and in four of 25 patients (16 %) with head and neck melanoma. In six of 30 asymptomatic patients with high risk melanoma (20 %), whole body PET detected occult distant metastases. Conclusion: Both SLNB and whole body PET were reliable methods to detect clinically occult metastases in patients with cutaneous melanoma. This upstaging altered the treatment in each case.

Exposure to Tobacco Smoke and Markers of Subclinical Atherosclerosis in Children and Adolescents. The STRIP Study.

Background: Measurement of serum cotinine, a major metabolite of nicotine, provides a valid marker for quantifying exposure to tobacco smoke. Exposure to tobacco smoke causes vascular damage by multiple mechanisms, and it has been acknowledged as a risk factor for atherosclerosis. Multifactorial atherosclerosis begins in childhood, but the relationship between exposure to tobacco smoke and arterial changes related to early atherosclerosis have not been studied in children. Aims: The aim of the present study was to evaluate exposure to tobacco smoke with a biomarker, serum cotinine concentration, and its associations with markers of subclinical atherosclerosis and lipid profile in school-aged children and adolescents. Subjects and Methods: Serum cotinine concentration was measured using a gas chromatographic method annually between the ages 8 and 13 years in 538-625 children participating since infancy in a randomized, prospective atherosclerosis prevention trial STRIP (Special Turku coronary Risk factor Intervention Project). Conventional atherosclerosis risk factors were measured repeatedly. Vascular ultrasound studies were performed among 402 healthy 11-year-old children and among 494 adolescents aged 13 years. Results: According to serum cotinine measurements, a notable number of the school aged children and adolescents were exposed to tobacco smoke, but the exposure levels were only moderate. Exposure to tobacco smoke was associated with decreased endothelial function as measured with flow-mediated dilation of the brachial artery, decreased elasticity of the aorta, and increased carotid and aortic intima-media thickness. Longitudinal exposure to tobacco smoke was also related with increased apolipoprotein B and triglyceride levels in 13-year-old adolescents, whose body mass index and nutrient intakes did not differ. Conclusions: These findings suggest that exposure to tobacco smoke in childhood may play a significant role in the development of early atherosclerosis. Key Words: arterial elasticity, atherosclerosis, children, cotinine, endothelial function, environmental tobacco smoke, intima-media thickness, risk factors, ultrasound

Metabolic syndrome – early cardio-metabolic, vascular and hepatic changes

Background: Metabolic syndrome (MetS) is a combination of several cardio-metabolic risk factors including obesity, hyperglycemia, hypertension and dyslipidemia. MetS has been associated with increased levels of apolipoprotein B (apoB) and low-density lipoprotein oxidation (OxLDL) and with an increased risk of cardiovascular disease and non-alcoholic fatty liver disease. Aims: To establish the relation of apoB and OxLDL with the MetS development and to determine the status of MetS as a risk factor for adverse liver changes and for subclinical atherosclerosis. Subjects and Methods: The present thesis is part of the two large scale population-based, prospective, observational studies. Cardiovascular Risk in Young Finns study was launched in 1980 including 3,596 subjects aged 3-18 years. Thereafter follow-up studies have been conducted regularly. In the latest follow-ups that were performed in 2001 (N=2,283) and 2007 (N=2,204), non-invasive ultrasound studies were introduced to the study protocol to measure subclinical atherosclerosis i.e. carotid intima-media thickness (IMT), carotid artery distensibility (Cdist) and brachial flow-mediated dilatation (FMD). Alanine-aminotransferase (ALT) and gammaglutamyltransferase (GGT) were measured in 2007 to assess liver function. The Bogalusa Heart Study is a long-term epidemiologic study of cardiovascular risk factors launched in 1972 in a biracial community of Bogalusa, Louisiana, USA. Total of 374 youths (aged 9-18 years at baseline in 1984-88) who underwent non-invasive ultrasound studies of the carotid artery as adults, were included in the analyses of the present thesis. Results: The odds ratios (95% confidence intervals) for MetS incidence during a 6-year follow-up by quartiles of apoB were 2.0(1.0-3.8) for the second quartile, 3.1(1.7-5.7) for the third quartile and 4.2(2.3-7.6) for the fourth quartile. OxLDL was not independently associated with incident MetS. Youth (aged 9-18 years) with MetS or with high body mass index were at 2-3 times the risk of having MetS, high IMT, and type 2 diabetes 24-years later as adults. IMT increased 79±7μm (mean±SEM) in subjects with MetS and 42±2μm in subjects without the MetS (P<0.0001) during 6- years. Subjects who lost the MetS diagnosis during 6-year follow-up had reduced IMT progression compared to persistent MetS group (0.036±0.005vs.0.079±0.010 mm, P=0.001) and reduced Cdist change compared to incident MetS group (-0.12±0.05vs.-0.38±0.10 %/mmHg, P=0.03) over 6-year follow-up. MetS predicted elevated ALT (β±SEM=0.380±0.052, P<0.0001 in men and 0.160±0.052, P=0.002 in women) and GGT (β±SEM=0.240±0.058, P<0.0001 in men and 0.262±0.053, P<0.0001 in women) levels after 6-years. Conclusions: These findings suggest that apoB may give additional information on early metabolic disturbances predisposing MetS. MetS may be used to identify individuals at increased risk of developing atherosclerosis and non-alcoholic liver disease. However, recovery from the MetS may have positive effects on liver and vascular properties.

Shapes and sizes : body image, body dissatisfaction and disordered eating in relation to gender and gender identity

Syftet med denna avhandling var att empiriskt undersöka kroppsbild, kroppsmissnöje och ätstörningssymptom hos vuxna i relation till kön och könsidentitet. Även sexuell kroppsbild studerades. Data samlades in via en populationsbaserad frågeformulärsstudie (11,468 deltagare) samt en intervjustudie med 20 transpersoner. Kvinnor rapporterade mer kroppsmissnöje och ätstörningssymptom än män. Till exempel uppgav mer än hälften av kvinnorna och en tredjedel av männen att de uppfattade sig som mindre attraktiva än de önskade att de var. Mer än hälften av kvinnorna och en tredjedel av männen uppgav sig banta, och självframkallade kräkningar rapporterades av var tionde kvinna och var hundrade man. Könsidentitetskonflikt var associerat med högre nivåer av kroppsnöje och ätstörningssymptom. Majoriteten av de intervjuade transpersonerna rapporterade omfattande missnöje med sina kroppar, särskilt gällande sexuell kroppsbild, samt ätstörningssymptom. Könskorrigering uppgavs i huvudsak lindra kroppsmissnöje och ätstörningssymptom. Vårdpersonal bör vara medveten om att kroppsmissnöje och ätstörningssymptom berör både vuxna kvinnor och män. Missnöje med de sexuella delarna av kroppen förefaller vara relativt vanligt bland vuxna och bör inte förbises. Vårdpersonal som arbetar med transpersoner bör vara medvetna om hur djupt och omfattande dessa personers kroppsmissnöje kan vara, samt uppmärksamma en eventuellt förhöjd risk för ätstörningssymptom. Det är även värt att notera att könskorrigering kan lindra kroppsmissnöje och ätstörningssymptom hos transpersoner.

Individual dietary counselling during and after pregnancy: Impact on diet and body weight

In Finland, maternity and child health clinics play a key role in promoting health in young families. Currently, obesity causes the greatest challenges to clinics. In obese pregnant women, an increased risk for metabolic diseases exist which can affect both the mother and child. The purpose of this thesis was to explore the role of dietary counselling: in Finnish health clinics; in the regulation of dietary intake; and in affecting the body weight of women. The main aim was to test the effect of dietary counselling and probiotic intervention on dietary intake and maternal body weight during and after pregnancy. In addition to dietary counselling, the effect of other factors, such as eating behaviour on dietary intake and body weight control after pregnancy was assessed. Another aim was also to evaluate dietary counselling practices by nurses (n = 327) in Finnish health clinics assessed by a questionnaire. At the beginning of the pregnancy, women (n = 256) enrolled in a dietary intervention study, were randomised into three groups. One group received dietary counselling with probiotics, one had counselling with placebo and the third group was the control group. The control group consisted of women whom did not receive counselling and took placebo. Probiotics and placebo supplements were used until the end of exclusive breastfeeding or six months after pregnancy. Women were followed from early pregnancy up to four years after pregnancy. Follow-up visits took place three times during pregnancy, at one and six months, and one, two and four years after pregnancy. Dietary counselling, provided by a nutritionist, aimed to influence the quality of dietary fat intake. Dietary counselling is important to provide in clinics, as determined by the nurses, and these nurses expressed a want to improve their own nutritional knowledge through education. The nurses had varying knowledge of current dietary recommendations. Dietary counselling for women during and after pregnancy resulted in beneficial changes in dietary intake up to one year after pregnancy and body weight and waist circumference up to four years after pregnancy. Probiotics had a beneficial effect together with dietary counselling on waist circumference until one year after pregnancy, but not throughout the long term, four years after pregnancy. Other factors, such as eating behaviour, associated with dietary intake and body weight control after pregnancy. Specifically, dietary recommendations are reached amongst women whom had high cognitive restraint in their eating behaviour and did not demonstrate uncontrolled eating. Overweight women more frequently emotionally ate compared to normal weight women and women with central adiposity related more frequently to having an uncontrolled eating behaviour than women with normal waist circumference. In addition, being overweight prior to pregnancy and excessive weight gain during pregnancy associated with increased body weight retention after pregnancy. This study showed that individual dietary counselling is useful in influencing dietary intake which adheres to dietary recommendations and this counselling influences, favourably, body weight after pregnancy. Especially, women with the risk for weight retention, such as women who have emotional and uncontrolled eating behaviours, who were overweight prior to pregnancy or those who had excessive weight gain during pregnancy, may benefit from individual dietary counselling. This study underscores the need to develop dietary counselling practices for pregnant women and their follow-up after pregnancy in Finnish health clinics. These practices include increasing the efficacy of the counselling such as collaboration with families, having knowledgable health professionals and having sufficient resources.

Oxidized LDL and physical fitness in healthy young men: associations with body composition, smoking, metabolic syndrome and androgen status

Background: In the past, oxidized low density lipoprotein (ox-LDL) has been associated with an unbeneficial lipid profile. This atherogenic lipid profile increases the risk of atherosclerotic cardiovascular diseases. Physical fitness has substantial effect on serum lipoprotein concentration as well as body composition and humoral responses, however interrelationships between ox-LDL and physical fitness have not been widely examined in a nationally representative sample. Aims: This thesis evaluates how cardiorespiratory and muscular fitness associate with ox-LDL lipids and how the other known risk factors of atherosclerosis might alter these associations. Subjects and Methods: The study cohort consisted of 846 healthy young males (mean age 25.1, SD 4.6) who were gathered by voluntary nationwide recruitment. Each participant conducted a series of physical fitness tests (cardiorespiratory and muscular fitness) and answered a detailed questionnaire that included lifestyle habits (i.e. smoking and leisuretime physical activity). Venous blood samples including ox-LDL and serum lipids were also collected. Results: Higher levels of ox-LDL were found in overweight and obese men, however, high cardiorespiratory fitness seemed to protect the overweight from high levels of ox-LDL. Young men who smoked and had poor cardiorespiratory or muscular fitness possessed a higher concentration of ox-LDL lipids when compared to comparable levels of cardiorespiratory or muscular fitness non-smoking young men. Metabolic syndrome was associated with increased levels of ox-LDL and high levels of ox-LDL combined with poor cardiorespiratory and abdominal muscle fitness seems to predict metabolic syndrome in young men. Also, participants with poor cardiorespiratory fitness and low levels of testosterone had higher levels of ox-LDL when compared to participants with high cardiorespiratory fitness / low testosterone as well as those with poor cardiorespiratory fitness / high testosterone. Conclusions: Good cardiorespiratory and muscular fitness protects young men from increased levels of ox-LDL lipids. This association was discovered in young men who were categorized as being overweight, smokers, metabolic syndrome or with low levels of testosterone. Being fit seems to prevent higher levels of ox-LDL, even in young healthy

Chromatoid body mediated RNA regulation in mouse male germline

Male germ cell differentiation, spermatogenesis is an exceptional developmental process that produces a massive amount of genetically unique spermatozoa. The complexity of this process along with the technical limitations in the germline research has left many aspects of spermatogenesis poorly understood. Post-meiotic haploid round spermatids possess the most complex transcriptomes of the whole body. Correspondingly, efficient and accurate control mechanisms are necessary to deal with the huge diversity of transcribed RNAs in these cells. The high transcriptional activity in round spermatids is accompanied by the presence of an uncommonly large cytoplasmic ribonucleoprotein granule, called the chromatoid body (CB) that is conjectured to participate in the RNA post-transcriptional regulation. However, very little is known about the possible mechanisms of the CB function. The development of a procedure to isolate CBs from mouse testes was this study’s objective. Anti-MVH immunoprecipitation of cross-linked CBs from a fractionated testicular cell lysate was optimized to yield considerable quantities of pure and intact CBs from mice testes. This protocol produced reliable and reproducible data from the subsequent analysis of CB’s protein and RNA components. We found that the majority of the CB’s proteome consists of RNA-binding proteins that associate functionally with different pathways. We also demonstrated notable localization patterns of one of the CB transient components, SAM68 and showed that its ablation does not change the general composition or structure of the CB. CB-associated RNA analysis revealed a strong accumulation of PIWI-interacting RNAs (piRNAs), mRNAs and long non-coding RNAs (lncRNAs) in the CB. When the CB transcriptome and proteome analysis results were combined, the most pronounced molecular functions in the CB were related to piRNA pathway, RNA post-transcriptional processing and CB structural scaffolding. In addition, we demonstrated that the CB is a target for the main RNA flux from the nucleus throughout all steps of round spermatid development. Moreover, we provided preliminary evidence that those isolated CBs slice target RNAs in vitro in an ATPdependent manner. Altogether, these results make a strong suggestion that the CB functions involve RNA-related and RNA-mediated mechanisms. All the existing data supports the hypothesis that the CB coordinates the highly complex haploid transcriptome during the preparation of the male gametes for fertilization. Thereby, this study provides a fundamental basis for the future functional analyses of ribonucleoprotein granules and offers also important insights into the mechanisms governing male fertility.

Seasonal variation in migratory body condition, corticosterone secretion, oxidative stress and biotransformation activity in barn swallows (Hirundo rustica L.)

I studied the associations between migration-related physiological regulation (corticosterone) and body condition of barn swallows (Hirundo rustica L.). An additional purpose was to determine whether oxidative stress and biotransformation activity vary seasonally. Since physiological regulation, biotransformation activity and the stress involved may be important factors for body condition during migration; they may have direct effects on migration success. This in turn may influence other important life history stages, such as breeding and moult. In the thesis I used barn swallow data of the Finnish Ringing Centre (1997–2009), consisting of all juveniles ringed in the nests and recaptured from night roosts later the same autumn. Before the autumn migration in Finland I also captured, ringed and sampled barn swallows from night roosts in 2003, 2006, 2007 and 2011. Samples preceding spring migration in South Africa were collected in 2007. Juvenile barn swallows started to migrate southward in mid-August (first broods). Second broods started their migration at a younger age and almost a month later than first broods (mid-September). Barn swallows increased body mass and accumulated fat for the autumn migration. In the course of the autumn they seemed to be able to prevent the loss of energy already accumulated, since the proportional overnight mass loss, fat loss and faecal production decreased. Surprisingly, corticosterone, the major energy-regulating hormone in birds, seemed not to be involved in the fuelling process. Previous studies with warblers, sparrows and shorebirds had shown that during migration, the baseline levels of corticosterone were elevated in order to facilitate fuelling. It is possible that for Finnish barn swallows the most important fuelling place is in southern Europe, since northern and eastern populations migrate via the Balkan Peninsula. However, the adrenocortical stress response of Finnish barn swallows in good body condition was lower than that of those in poor body condition. Birds clearly suppressed the response, probably to prevent the catabolic effects of excessive corticosterone levels; birds cannot afford to lose muscle mass before migration. South African barn swallows had high levels of baseline corticosterone, but this may have been associated with the high oxidative damage and biotransformation activity of those birds. Barn swallows in spring and summer had low biotransformation activity and intermediate oxidative stress, which was probably related to breeding. Autumn birds had low biotransformation activity and oxidative stress but high redox enzyme activities in some migration-related enzymes.