Showing papers by "University of Turku published in 2004"

Dissecting the spatial structure of ecological data at multiple scales

Abstract: Spatial structures may not only result from ecological interactions, they may also play an essential functional role in organizing the interactions. Modeling spatial patterns at multiple spatial and temporal scales is thus a crucial step to understand the functioning of ecological communities. PCNM (principal coordinates of neighbor matrices) analysis achieves a spectral decomposition of the spatial relationships among the sampling sites, creating variables that correspond to all the spatial scales that can be perceived in a given data set. The analysis then finds the scales to which a data table of interest responds. The significant PCNM variables can be directly interpreted in terms of spatial scales, or included in a procedure of variation decomposition with respect to spatial and environmental components. This paper presents four applications of PCNM analysis to ecological data representing combinations of: transect or surface data, regular or irregular sampling schemes, univariate or multivariate data. The data sets include Amazonian ferns, tropical marine zooplankton, chlorophyll in a marine lagoon, and oribatid mites in a peat bog. In each case, new ecological knowledge was obtained through PCNM analysis.

Connections between attitudes, group norms, and behaviour in bullying situations:

Abstract: We examined the connections between attitudes, group norms, and students’ behaviour in bullying situations (bullying others, assisting the bully, reinforcing the bully, defending the victim, or staying outside bullying situations). The participants were 1220 elementary school children (600 girls and 620 boys) from 48 school classes from Grades four, five, and six, i.e., 9–10, 10–11, and 11–12 years of age. Whereas attitudes did predict behaviour at the student level in most cases (although the effects were moderate after controlling for gender), the group norms could be used in explaining variance at the classroom level, especially in the upper grades. The class context (even if not classroom norms specifically) had more effect on girls’ than on boys’ bullying-related behaviours.

Combinatorics on Words

Abstract: Words (strings of symbols) are fundamental in computer processing. Indeed, each bit of data processed by a computer is a string, and nearly all computer software use algorithms on strings. There are also abundant supply of applications of these algorithms in other areas such as data compression, DNA sequence analysis, computer graphics, cryptography, and so on.

What is “enterprise education”? An analysis of the objectives and methods of enterprise education programmes in four European countries

Abstract: This paper explores what constitutes “enterprise education” in four European countries. It proposes a conceptual schema for capturing the various objectives of enterprise education programmes and initiatives. This conceptual schema is then used to categorise the objectives of 50 enterprise programmes from Austria, Finland, Ireland, and the UK. The paper reviews the teaching/learning methods used in these programmes. It discusses what factors are associated with “effective” enterprise education, illustrating the discussion with “best practice” from the programmes studied. The paper argues that in order to operate effective enterprise education programmes, policy makers and educators need a thorough understanding of the diverse and alternative aims and objectives of enterprise education interventions, of the alternative forms such interventions can take, and of the need to “train the trainers”.

Communities of Networked Expertise: Professional and Educational Perspectives

Abstract: Introduction. Part I. The Knowledge-Acquisition Perspective. Expert Knowledge as the Basis of Human Competence. Dynamic Development of Expertise. Organizational Support for Dynamic Development of Expertise. Part II. The Participation Perspective. Participation in Communities of Expertise. Networks of Knowledge Sharing. Facilitating Organizational Intelligence through Knowledge Management. Part III. The Knowledge-Creation Perspective. Models of Innovative Knowledge Communities. Role of Conceptual and Material Artifacts in Knowledge Creation. The Dynamic Nature of Innovative Knowledge Communities. Individual and Social Aspects of Knowledge Creation. Part IV. Educating for Networked Expertise. Acquisition Perspective: Developing Basic Knowledge and Competencies for Expertise. Participation Perspective: Organizing Networking Relations Between Learners and Expert Communities. Knowledge-Creation Perspective: Facilitating Progressive Inquiry in Education. Concluding Remarks: Relational Nature of Networked Expertise.

Dynamics of photosystem II: a proteomic approach to thylakoid protein complexes

Abstract: Oxygenic photosynthesis produces various radicals and active oxygen species with harmful effects on photosystem II (PSII). Such photodamage occurs at all light intensities. Damaged PSII centres, however, do not usually accumulate in the thylakoid membrane due to a rapid and efficient repair mechanism. The excellent design of PSII gives protection to most of the protein components and the damage is most often targeted only to the reaction centre D1 protein. Repair of PSII via turnover of the damaged protein subunits is a complex process involving (i) highly regulated reversible phosphorylation of several PSII core subunits, (ii) monomerization and migration of the PSII core from the grana to the stroma lamellae, (iii) partial disassembly of the PSII core monomer, (iv) highly specific proteolysis of the damaged proteins, and finally (v) a multi-step replacement of the damaged proteins with de novo synthesized copies followed by (vi) the reassembly, dimerization, and photoactivation of the PSII complexes. These processes will shortly be reviewed paying particular attention to the damage, turnover, and assembly of the PSII complex in grana and stroma thylakoids during the photoinhibition–repair cycle of PSII. Moreover, a two-dimensional Blue-native gel map of thylakoid membrane protein complexes, and their modification in the grana and stroma lamellae during a high-light treatment, is presented.

Fitness benefits of prolonged post-reproductive lifespan in women

Abstract: Most animals reproduce until they die, but in humans, females can survive long after ceasing reproduction In theory, a prolonged post-reproductive lifespan will evolve when females can gain greater fitness by increasing the success of their offspring than by continuing to breed themselves Although reproductive success is known to decline in old age, it is unknown whether women gain fitness by prolonging lifespan post-reproduction Using complete multi-generational demographic records, we show that women with a prolonged post-reproductive lifespan have more grandchildren, and hence greater fitness, in pre-modern populations of both Finns and Canadians This fitness benefit arises because post-reproductive mothers enhance the lifetime reproductive success of their offspring by allowing them to breed earlier, more frequently and more successfully Finally, the fitness benefits of prolonged lifespan diminish as the reproductive output of offspring declines This suggests that in female humans, selection for deferred ageing should wane when one's own offspring become post-reproductive and, correspondingly, we show that rates of female mortality accelerate as their offspring terminate reproduction

Large–scale geographical variation confirms that climate change causes birds to lay earlier

Abstract: Advances in the phenology of organisms are often attributed to climate change, but alternatively, may reflect a publication bias towards advances and may be caused by environmental factors unrelated to climate change. Both factors are investigated using the breeding dates of 25 long-term studied populations of Ficedula flycatchers across Europe. Trends in spring temperature varied markedly between study sites, and across populations the advancement of laying date was stronger in areas where the spring temperatures increased more, giving support to the theory that climate change causally affects breeding date advancement.

Interrelations Between Brachial Endothelial Function and Carotid Intima-Media Thickness in Young Adults The Cardiovascular Risk in Young Finns Study

Abstract: Background— Endothelial vasodilator dysfunction and carotid intima-media thickening (IMT) are 2 indicators of subclinical cardiovascular disease. We examined their correlation and interaction with risk factors in a large, community-based cohort of young adults. Methods and Results— As part of the longitudinal Cardiovascular Risk in Young Finns Study, we measured endothelium-dependent brachial artery flow–mediated dilatation (FMD) and carotid artery IMT by ultrasound in 2109 healthy adults aged 24 to 39 years. FMD was inversely associated with IMT (P≤0.001) in a multivariate model adjusted for age, sex, brachial vessel size, and several risk variables. The subjects with age- and sex-specific FMD values in the extreme deciles were classified into groups of impaired (n=204, FMD=1.1±1.4%, mean±SD) and enhanced (n=204, FMD=16.3±2.9%) FMD response. The number of risk factors was correlated with increased IMT in subjects with an impaired FMD response (P ...

Longitudinal changes in diet from childhood into adulthood with respect to risk of cardiovascular diseases: The Cardiovascular Risk in Young Finns Study.

Abstract: Objective To assess nutrient intakes relevant in the prevention of cardiovascular diseases (CVD) among young adults in Finland and to find past and present determinants of quality of diet. Design Prospective study, 21 years of follow-up. Setting The Cardiovascular Risk in Young Finns Study, Finland. Subjects At baseline in 1980: 3569 children aged 3-18 y participated (83% of those invited), and every second of them (1780) were selected to the dietary study. At follow-ups in 1986 and 2001: 1200 and 1037 of the original sample, respectively, participated. Methods Food consumption was assessed using 48-h dietary recall. Intakes in 2001 were compared with those obtained in 1980 and 1986. Nutrients selected for further examination were those implicated in the risk of CVD: saturated, monounsaturated, polyunsaturated and n-3 fatty acids, fibre and salt. An index describing the quality of adulthood diet was constructed. Multivariate logistic regression was used to identify independent childhood and adulthood determinants of the quality index. Results The average intakes showed substantial changes since 1980. Intakes of fat and saturated fat had decreased, while the consumption of vegetables and fruit had increased. However, a great disparity was present between the recommended levels and actual intakes for many of the nutrients, particularly salt, saturated fat and fibre. Intake of fat and consumption of vegetables in childhood and physical activity in adulthood were important health behavioural determinants of the cardiovascular quality of the adult diet. Socio-demographic factors, including education of the subject and their parents, had no significant associations with diet. Conclusions While intakes of energy and nutrients have changed favourably in Finnish young adults between 1980 and 2001 with regard to the risk of CVD, they are still far from recommended levels. Childhood diet is a significant determinant of adult diet even after 21 y. Sponsorship This study was supported by the Academy of Finland (grant 77841) and Juho Vainio Foundation.

An Introduction to Silanes and Their Clinical Applications in Dentistry

Abstract: Purpose: This overview presents a description of organofunctional trialkoxysilane coupling agents (silanes), their chemistry, properties, use, and some of the main clinical experiences in dentistry. Materials and Methods: The main emphasis was on major dental journals that have been reviewed from 1958 up to the latest research news from 2002. A MEDLINE search with the key words “dental silanes” was used. Special silane literature and journals outside dentistry were also cited. Results: The main emphasis is on the use of silanes in prosthetic and restorative dentistry. Clinical relevance was based mainly on either short- or long-term tests. The interpretation of various results is not given, mainly because of controversial observations that may be very difficult to explain. Nevertheless, the majority of the clinical results pointed to silanes playing a significant role in the adhesion process. Silane reaction mechanisms were not entirely understood, and there exist several theories for bonding mechanisms for silanes and substrates. Conclusion: Dental materials offer a continuously challenging forum for silanes, and silanes will play an essential role in material development. Publ. in: Int J Prosthodont 2004;17:155–164.

Nurse competence scale: development and psychometric testing.

Abstract: Background. Self-assessment assists nurses to maintain and improve their practice by identifying their strengths and areas that may need to be further developed. Professional competence profiles encourage them to take an active part in the learning process of continuing education. Although competence recognition offers a way to motivate practising nurses to produce quality care, few measuring tools are available for this purpose. Aim. This paper describes the development and testing of the Nurse Competence Scale, an instrument with which the level of nurse competence can be assessed in different hospital work environments. Methods. The categories of the Nurse Competence Scale were derived from Benner's From Novice to Expert competency framework. A seven-step approach, including literature review and six expert groups, was used to identify and validate the indicators of nurse competence. After a pilot test, psychometric testing of the Nurse Competence Scale (content, construct and concurrent validity, and internal consistency) was undertaken with 498 nurses. The 73-item scale consists of seven categories, with responses on a visual analogy scale format. The frequency of using competencies was additionally tested with a four-point scale. Results. Self-assessed overall scores indicated a high level of competence across categories. The Nurse Competence Scale data were normally distributed. The higher the frequency of using competencies, the higher was the self-assessed level of competence. Age and length of work experience had a positive but not very strong correlation with level of competence. According to the item analysis, the categories of the Nurse Competence Scale showed good internal consistency. Conclusion. The results provide strong evidence of the reliability and validity of the Nurse Competence Scale.

Influence of mode of delivery on gut microbiota composition in seven year old children

Abstract: Intestinal microbiota development begins immediately following birth.1 The composition of the infant’s evolving microbiota is initially defined by the mother, the source of the newborn’s first microbial inoculum. Colonising bacteria rapidly adapt to breast milk and epithelial mucins as sources of nutrients. The prevalence of caesarean section delivery in Western countries is increasing. Caesarean born babies are deprived of contact with the maternal/vaginal microbiota and the first exposure is characterised by a lack of strict anaerobes and the presence of facultative anaerobes such as Clostridium species.2 Caesarean born infants have a more slowly diversifying microbiota, with differences reported from normally born infants, even after six months of age. Aberrancies in early microbiota acquisition can affect immunophysiological development with a heightened disease risk.2,3 This …

Effects of habitat cover, landscape structure and spatial variables on the abundance of birds in an agricultural–forest mosaic

Abstract: Summary 1 Numerical studies of the relationship between birds and their habitat are important because they provide understanding of the impacts of natural and human factors on avian diversity. However, collinearity between explanatory variables and spatial autocorrelation can hamper the detection of key environmental factors underlying bird–environment relationships identified by traditional regression approaches. This study utilized two alternative statistical methods to address these difficulties in biodiversity modelling. 2 We examined bird abundance patterns, spatial structure and relationship to environmental factors in an agricultural–forest mosaic landscape in Finland. We used data from 105 grid squares each 25 ha in size. Using variation partitioning and hierarchical partitioning methods, we determined the independent and joint effects of habitat cover, landscape structure and spatial variables on the total number of bird pairs and that of agricultural bird pairs. 3 The explanatory variables highlighted as important predictors of bird patterns by the two methods generally coincided well. The total number of bird pairs was negatively related to agricultural land, and positively to cover of forests and landscape heterogeneity. However, a clear majority of the explained variation in bird patterns was related to the joint effect of predictors, and the independent contributions of predictors were small. The univariate importance of landscape heterogeneity decreased greatly if the habitat cover variables were considered simultaneously. 4 Most of the explained variation in the number of agricultural bird pairs was related to the joint effects of the explanatory variables. In addition, the independent effect of habitat cover variables was considerable and agricultural birds showed a positive relationship with semi-natural grasslands. 5 Synthesis and applications. Variation partitioning and hierarchical partitioning approaches provide deeper insights into bird–environment relationships than traditional regression methods. This is particularly so when they are employed in a complementary manner. Our results indicate that a major part of the spatial structure in bird patterns in agricultural–forest mosaics can be caused by the clumping of habitats either preferred or avoided by birds. Moreover, at a scale of 25 ha, the abundance of bird pairs is not necessarily related to landscape heterogeneity as such, but depends more on the distribution of the most important habitats for birds.

Phenotypic characterization of regulatory T cells in the human decidua

Abstract: Pregnancy is a unique situation for the maternal immune system. We have studied and identified a CD4+CD25+ regulatory T (Treg) cell population isolated from the human decidua. This mucosal surface in the uterus is in direct contact with semiallogenic fetal cells. We observed that about 14% of the decidual CD4+ T cells have the CD4+CD25+ phenotype. The decidual CD4+CD25+ T cells expressed high frequency of intracellular CTLA-4 (CTLA-4i). The majority of CD4+CD25+CTLA-4i+ cells were also positive for GITR and OX40, typical markers for human Treg cells. The frequency of CD4+CD25+ T cells in the peripheral blood from pregnant women was found to be increased during the first and second trimester of gestation when compared to nonpregnant controls. Being an important molecule for Treg cells, the role of CTLA-4 in the regulation of indoleamine 2,3-dioxygenase (IDO) expression was also examined. The stimulation with CTLA-4Ig did not increase IDO mRNA expression in CD14+ cells from pregnant women, while IFN-gamma was observed to up-regulate IDO expression. The presence of Treg cells in the human decidua suggests that these cells are important in protecting the fetus from alloreactive immune responses at the maternal-fetal interface.

PASSCLAIM - gut health and immunity

Abstract: Background The gut and immune system form a complex integrated structure that has evolved to provide effective digestion and defence against ingested toxins and pathogenic bacteria. However, great variation exists in what is considered normal healthy gut and immune function. Thus, whilst it is possible to measure many aspects of digestion and immunity, it is more difficult to interpret the benefits to individuals of variation within what is considered to be a normal range. Nevertheless, it is important to set standards for optimal function for use both by the consumer, industry and those concerned with the public health. The digestive tract is most frequently the object of functional and health claims and a large market already exists for gut-functional foods worldwide. Aim To define normal function of the gut and immune system and describe available methods of measuring it. Results We have defined normal bowel habit and transit time, identified their role as risk factors for disease and how they may be measured. Similarly, we have tried to define what is a healthy gut flora in terms of the dominant genera and their metabolism and listed the many, varied and novel methods for determining these parameters. It has proved less easy to provide boundaries for what constitutes optimal or improved gastric emptying, gut motility, nutrient and water absorption and the function of organs such as the liver, gallbladder and pancreas. The many tests of these functions are described. We have discussed gastrointestinal well being. Sensations arising from the gut can be both pleasant and unpleasant. However, the characteristics of well being are ill defined and merge imperceptibly from acceptable to unacceptable, a state that is subjective. Nevertheless, we feel this is an important area for future work and method development. The immune system is even more difficult to make quantitative judgements about. When it is defective, then clinical problems ensure, but this is an uncommon state. The innate and adaptive immune systems work synergistically together and comprise many cellular and humoral factors. The adaptive system is extremely sophisticated and between the two arms of immunity there is great redundancy, which provides robust defences. New aspects of immune function are discovered regularly. It is not clear whether immune function can be "improved". Measuring aspects of immune function is possible but there is no one test that will define either the status or functional capacity of the immune system. Human studies are often limited by the ability to sample only blood or secretions such as saliva but it should be remembered that only 2% of lymphocytes circulate at any given time, which limits interpretation of data. We recommend assessing the functional capacity of the immune system by: measuring specific cell functions ex vivo measuring in vivo responses to challenge, e. g. change in antibody in blood or response to antigens determining the incidence and severity of infection in target populations during naturally occurring episodes or in response to attenuated pathogens.

Specific in vivo phosphorylation sites determine the assembly dynamics of vimentin intermediate filaments.

Abstract: Intermediate filaments (IFs) continuously exchange between a small, depolymerized fraction of IF protein and fully polymerized IFs. To elucidate the possible role of phosphorylation in regulating this equilibrium, we disrupted the exchange of phosphate groups by specific inhibition of dephosphorylation and by specific phosphorylation and site-directed mutagenesis of two of the major in vivo phosphorylation sites determined in this study. Inhibition of type-1 (PP1) and type-2A (PP2A) protein phosphatases in BHK-21 fibroblasts with calyculin-A, induced rapid vimentin phosphorylation in concert with disassembly of the IF polymers into soluble tetrameric vimentin oligomers. This oligomeric composition corresponded to the oligopeptides released by cAMP-dependent kinase (PKA) following in vitro phosphorylation. Characterization of the 32P-labeled vimentin phosphopeptides, demonstrated Ser-4, Ser-6, Ser-7, Ser-8, Ser-9, Ser-38, Ser-41, Ser-71, Ser-72, Ser-418, Ser-429, Thr-456, and Ser-457 as significant in vivo phosphorylation sites. A number of the interphase-specific high turnover sites were shown to be in vitro phosphorylation sites for PKA and protein kinase C (PKC). The effect of presence or absence of phosphate groups on individual subunits was followed in vivo by microinjecting PKA-phosphorylated (primarily S38 and S72) and mutant vimentin (S38:A, S72:A), respectively. The PKA-phosphorylated vimentin showed a clearly decelerated filament formation in vivo, whereas obstruction of phosphorylation at these sites by site-directed mutagenesis had no significant effect on the incorporation rates of subunits into assembled polymers. Taken together, our results suggest that elevated phosphorylation regulates IF assembly in vivo by changing the equilibrium constant of subunit exchange towards a higher off-rate.

Meta‐analysis of Trade‐offs among Plant Antiherbivore Defenses: Are Plants Jacks‐of‐All‐Trades, Masters of All?

Abstract: On the basis of physiological and ecological costs of defense allocation, most plant defense theories predict the occurrence of trade‐offs between resource investment in different types of antiherbivore defenses. To test this prediction, we conducted a meta‐analysis of 31 studies published in 1976–2002 that provided data on covariation of different defensive traits in plant genotypes. We found no overall negative association between different defensive traits in plants; instead, the relationship between defensive traits varied from positive to negative depending on the types of co‐occurring defenses. Evidence of trade‐off was found only between constitutive and induced defenses. Therefore, to a large extent, plants appear to be jacks‐of‐all‐trades, masters of all and may successfully produce several types of defense without paying considerable trade‐offs. Our survey thus provides little evidence that genetic trade‐offs between defensive traits significantly constrain the evolution of multiple de...

Persistence of rhinovirus and enterovirus RNA after acute respiratory illness in children.

Abstract: The persistence of rhinovirus and enterovirus RNAs was studied in the nasal secretions of children with acute expiratory wheezing (median age: 1.7 years). On admission, 84 samples from 161 (52%) children admitted to hospital were positive by reverse transcriptase-polymerase chain reaction (RT-PCR), which detects rhino- and enteroviruses simultaneously. Of the samples, 26 (16%) were positive for rhinovirus, 29 (18%) enterovirus and 29 (18%) nontypable rhino-enterovirus. After 2 weeks, 16 of these 84 (19%) samples were still positive. Rhinovirus RNA remained positive in 13 of 26 (50%) cases, whereas enterovirus RNA remained positive only in 1 of 29 (3%) cases (P=0.0001). Respiratory symptoms at 2 weeks or systemic glucocorticoid treatment during hospital stay were not related to the persistence of viral RNA. After 5 weeks, only one sample remained PCR-positive. Thirteen of the 79 (16%) asymptomatic control children were PCR-positive for respiratory picornavirus. Five of the 13 (38%) PCR-positive children developed respiratory symptoms in the following week. The study shows that after the onset of symptomatic respiratory infection enterovirus RNA may take 2-3 weeks and rhinovirus RNA 5-6 weeks to disappear from nasal mucus.

Burden of Influenza in Children in the Community

Abstract: BACKGROUND Influenza vaccination of healthy children is encouraged because children are frequently hospitalized for influenza-attributable illnesses. However, most children with influenza are treated as outpatients, and scarce data are available on the burden of influenza in these children. METHODS We performed a prospective study of respiratory infections in preenrolled cohorts of children < or = 13 years old during 2 consecutive respiratory seasons (2231 child-seasons of follow-up). At any sign of respiratory infection, we examined the children and obtained a nasal swab for the detection of influenza. The parents filled out daily symptom diaries. Of all the enrollees, 94% remained active participants in the study. RESULTS The average annual rate of influenza was highest (179 cases/1000 children) among children < 3 years old. Acute otitis media developed as a complication of influenza in 39.7% of children < 3 years old. For every 100 influenza-infected children < 3 years old, there were 195 days of parental work loss (mean duration, 3.2 days). CONCLUSIONS Influenza causes a substantial burden of illness on outpatient children and their families. Vaccination of children < 3 years old might be beneficial for reducing the direct and indirect costs of influenza in children.

Life satisfaction and depression in a 15-year follow-up of healthy adults.

Abstract: The aim of this study was to investigate the cross-sectional and longitudinal relationship between life satisfaction and depressive symptoms in healthy adults. This is a 15-year prospective cohort study with a nationwide sample of healthy Finnish adults (N=9679), aged 18–45, who responded to postal questionnaires in 1975, 1981 and 1990 including a 4-item life satisfaction (LS) scale (range 4–20) and, in 1990, the 21-item Beck Depression Inventory (BDI). A strong linear association was found between concurrent LS and BDI scales (r=0.6). With an LS cut-off point of 11/12, moderate/severe depression (BDI ≥ 19) was detected with 87% sensitivity, 88 % specificity and a 94% area under the ROC curve. Longitudinally, a strongly increased risk of moderate/severe depression in 1990 was observed among the dissatisfied (LS 12–20) compared with the satisfied (LS 4–6) in 1975 (OR=6.7; 95 %CI 4.2–10.9) and in 1981 (OR=10.4; 6.1–17.6). The 4-item LS scale can identify a group of healthy people from the general population with a high risk of having or developing depressive symptoms. Since low life satisfaction also indicates an elevated risk of other adverse health outcomes, the assessment of subjective well-being should be encouraged both in surveys and in clinical practice.

Mutations in SEC63 cause autosomal dominant polycystic liver disease.

Abstract: Mutations in PRKCSH, encoding the beta-subunit of glucosidase II, an N-linked glycan-processing enzyme in the endoplasmic reticulum (ER), cause autosomal dominant polycystic liver disease. We found that mutations in SEC63, encoding a component of the protein translocation machinery in the ER, also cause this disease. These findings are suggestive of a role for cotranslational protein-processing pathways in maintaining epithelial luminal structure and implicate noncilial ER proteins in human polycystic disease.

Variation in climate warming along the migration route uncouples arrival and breeding dates

Abstract: Migratory species are of special concern in the face of global climate change, since they may be affected by changes in the wintering area, along the migration route and at the breeding grounds. Here we show that migration and breeding times of a trans-Saharan migrant, the pied flycatcher Ficedula hypoleuca, closely follow local temperatures along the migration route and at the breeding grounds. Because of differences in long-term temperature trends of short within-spring periods, the migration period and the time interval between migration and breeding dates of this species have extended in SW Finland. Temperatures in northern parts of Central Europe have risen at the time when the first migrants arrive there, facilitating their migration northward. Temperatures later in the spring have not changed, and the last individuals arrive at the same time as before. The timing of breeding has not advanced because temperatures at the breeding site after arrival have not changed. These results show that the pied flycatchers can speed up their migration in response to rising temperatures along the migration route. Our results strongly indicate that the effects of climate change have to be studied at the appropriate time and geographical scales for each species and population concerned.

HPV infections and tonsillar carcinoma

Abstract: Since human papillomavirus (HPV) was first linked to laryngeal/oral carcinomas in 1983, several studies have confirmed its causal role in a subgroup of upper aerodigestive tract tumours. Of the non-genital cancers, tonsillar carcinomas (TCs) have the strongest association with HPV. By the end of 2002, 432 TCs had been analysed for HPV DNA. Overall detection rate was 51%, with HPV-16 being the most prevalent (84%). The original proposal that HPV-33 would be the most frequent HPV in TCs has not been confirmed, being present in only 4.6% of cases. HPV copy numbers are similar to those found in genital carcinomas (10–300 copies/cell), although HPV is mainly episomal in TC. The importance of this observation is unclear, although a role for subepithelial proliferative lymphatic tissue has been speculated. Patients with HPV-16 positive tumours have better overall and disease specific survival than HPV negative patients. They are also younger and the association with conventional risk factors—smoking and drinking—is less significant than in HPV negative patients. Thus, recent data suggest a distinct pattern for HPV-16 positive TCs.

C957T polymorphism of the dopamine D2 receptor (DRD2) gene affects striatal DRD2 availability in vivo

Abstract: C957T polymorphism of the dopamine D2 receptor (DRD2) gene affects striatal DRD2 availability in vivo