17 resultados para HUMAN BODY
em Helda - Digital Repository of University of Helsinki
Resumo:
Human body is in continuous contact with microbes. Although many microbes are harmless or beneficial for humans, pathogenic microbes possess a threat to wellbeing. Antimicrobial protection is provided by the immune system, which can be functionally divided into two parts, namely innate and adaptive immunity. The key players of the innate immunity are phagocytic white blood cells such as neutrophils, monocytes, macrophages and dendritic cells (DCs), which constantly monitor the blood and peripheral tissues. These cells are armed for rapid activation upon microbial contact since they express a variety of microbe-recognizing receptors. Macrophages and DCs also act as antigen presenting cells (APCs) and play an important role in the development of adaptive immunity. The development of adaptive immunity requires intimate cooperation between APCs and T lymphocytes and results in microbe-specific immune responses. Moreover, adaptive immunity generates immunological memory, which rapidly and efficiently protects the host from reinfection. Properly functioning immune system requires efficient communication between cells. Cytokines are proteins, which mediate intercellular communication together with direct cell-cell contacts. Immune cells produce inflammatory cytokines rapidly following microbial contact. Inflammatory cytokines modulate the development of local immune response by binding to cell surface receptors, which results in the activation of intracellular signalling and modulates target cell gene expression. One class of inflammatory cytokines chemokines has a major role in regulating cellular traffic. Locally produced inflammatory chemokines guide the recruitment of effector cells to the site of inflammation during microbial infection. In this study two key questions were addressed. First, the ability of pathogenic and non-pathogenic Gram-positive bacteria to activate inflammatory cytokine and chemokine production in different human APCs was compared. In these studies macrophages and DCs were stimulated with pathogenic Steptococcus pyogenes or non-pathogenic Lactobacillus rhamnosus. The second aim of this thesis work was to analyze the role of pro-inflammatory cytokines in the regulation of microbe-induced chemokine production. In these studies bacteria-stimulated macrophages and influenza A virus-infected lung epithelial cells were used as model systems. The results of this study show that although macrophages and DCs share several common antimicrobial functions, these cells have significantly distinct responses against pathogenic and non-pathogenic Gram-positive bacteria. Macrophages were activated in a nearly similar fashion by pathogenic S. pyogenes and non-pathogenic L. rhamnosus. Both bacteria induced the production of similar core set of inflammatory chemokines consisting of several CC-class chemokines and CXCL8. These chemokines attract monocytes, neutrophils, dendritic cells and T cells. Thus, the results suggest that bacteria-activated macrophages efficiently recruit other effector cells to the site of inflammation. Moreover, macrophages seem to be activated by all bacteria irrespective of their pathogenicity. DCs, in contrast, were efficiently activated only by pathogenic S. pyogenes, which induced DC maturation and production of several inflammatory cytokines and chemokines. In contrast, L. rhamnosus-stimulated DCs matured only partially and, most importantly, these cells did not produce inflammatory cytokines or chemokines. L. rhamnosus-stimulated DCs had a phenotype of "semi-mature" DCs and this type of DCs have been suggested to enhance tolerogenic adaptive immune responses. Since DCs have an essential role in the development of adaptive immune response the results suggest that, in contrast to macrophages, DCs may be able to discriminate between pathogenic and non-pathogenic bacteria and thus mount appropriate inflammatory or tolerogenic adaptive immune response depending on the microbe in question. The results of this study also show that pro-inflammatory cytokines can contribute to microbe-induced chemokine production at multiple levels. S. pyogenes-induced type I interferon (IFN) was found to enhance the production of certain inflammatory chemokines in macrophages during bacterial stimulation. Thus, bacteria-induced chemokine production is regulated by direct (microbe-induced) and indirect (pro-inflammatory cytokine-induced) mechanisms during inflammation. In epithelial cells IFN- and tumor necrosis factor- (TNF-) were found to enhance the expression of PRRs and components of cellular signal transduction machinery. Pre-treatment of epithelial cells with these cytokines prior to virus infection resulted in markedly enhanced chemokine response compared to untreated cells. In conclusion, the results obtained from this study show that pro-inflammatory cytokines can enhance microbe-induced chemokine production during microbial infection by providing a positive feedback loop. In addition, pro-inflammatory cytokines can render normally low-responding cells to high chemokine producers via enhancement of microbial detection and signal transduction.
Resumo:
Solid materials can exist in different physical structures without a change in chemical composition. This phenomenon, known as polymorphism, has several implications on pharmaceutical development and manufacturing. Various solid forms of a drug can possess different physical and chemical properties, which may affect processing characteristics and stability, as well as the performance of a drug in the human body. Therefore, knowledge and control of the solid forms is fundamental to maintain safety and high quality of pharmaceuticals. During manufacture, harsh conditions can give rise to unexpected solid phase transformations and therefore change the behavior of the drug. Traditionally, pharmaceutical production has relied on time-consuming off-line analysis of production batches and finished products. This has led to poor understanding of processes and drug products. Therefore, new powerful methods that enable real time monitoring of pharmaceuticals during manufacturing processes are greatly needed. The aim of this thesis was to apply spectroscopic techniques to solid phase analysis within different stages of drug development and manufacturing, and thus, provide a molecular level insight into the behavior of active pharmaceutical ingredients (APIs) during processing. Applications to polymorph screening and different unit operations were developed and studied. A new approach to dissolution testing, which involves simultaneous measurement of drug concentration in the dissolution medium and in-situ solid phase analysis of the dissolving sample, was introduced and studied. Solid phase analysis was successfully performed during different stages, enabling a molecular level insight into the occurring phenomena. Near-infrared (NIR) spectroscopy was utilized in screening of polymorphs and processing-induced transformations (PITs). Polymorph screening was also studied with NIR and Raman spectroscopy in tandem. Quantitative solid phase analysis during fluidized bed drying was performed with in-line NIR and Raman spectroscopy and partial least squares (PLS) regression, and different dehydration mechanisms were studied using in-situ spectroscopy and partial least squares discriminant analysis (PLS-DA). In-situ solid phase analysis with Raman spectroscopy during dissolution testing enabled analysis of dissolution as a whole, and provided a scientific explanation for changes in the dissolution rate. It was concluded that the methods applied and studied provide better process understanding and knowledge of the drug products, and therefore, a way to achieve better quality.
Resumo:
This dissertation is about ancient philosophers notions of mental illness, from Plato onwards. Mental illness here means disorders that, in ancient medical thought, were believed to originate in the body but to manifest themselves predominantly through mental symptoms. These illnesses were treated by physical means, which were believed to address the bodily cause of the illness, conceived of as an elemental imbalance or a state of cephalic stricture , for example. Sometimes the mental symptoms were addressed directly by psychotherapeutic means. The first and most important question explored concerns how the ancient philosophers responded to the medical notion of mental illness, and how they explained such illnesses in their theories of physiology and psychology. Although the illnesses are seldom discussed extensively, the philosophers were well aware of their existence and regarded their occurrence an indication of the soul s close dependence on the body. This called for a philosophical account. The second question addressed has to do with the ancient philosophers role as experts in mental problems of a non-medical kind, such as unwanted emotions. These problems were dubbed diseases of the soul , and the philosophers thus claimed to be doctors of the soul. Although the distinction between mental illnesses and diseases of the soul was often presented as rather obvious, there was some vagueness and overlap. There is still a third question that is explored, concerning the status of both mental illnesses and diseases of the soul as unnatural conditions, the role of the human body in the philosophical aetiologies of evil, and the medico-philosophical theories of psycho-physiological temperaments. This work consists of an introduction and five main chapters, focusing on Plato, Aristotle, the Stoics and Galen, and the Sceptics, the Epicureans and later Platonists. The sources drawn on are the original Greek and Latin philosophical and medical texts. It appears that the philosophers accepted the medical notion of mental illness, but interpreted it in various ways. The differences in interpretation were mostly attributable to differences in their theories of the soul. Although the distinction between mental illness and diseases of the soul was important, marking the boundary between the fields of expertise of medicine and philosophy, and of the individual s moral responsibilities, the problematic aspects of establishing it are discussed rather little in ancient philosophy. There may have been various reasons for this. The medical descriptions of mental illness are often extreme, symptoms of the psychotic type excluding the possibility of the condition being of the non-medical kind. In addition, the rigid normativeness of ancient philosophical anthropologies and their rigorous notion of human happiness decreased the need to assess the acceptability of individual variation in their emotional and intellectual lives and external behaviour.
Resumo:
The study explores the first appearances of Russian ballet dancers on the stages of northern Europe in 1908 1910, particularly the performances organized by a Finnish impresario, Edvard Fazer, in Helsinki, Stockholm, Copenhagen and Berlin. The company, which consisted of dancers from the Imperial Theatres of St. Petersburg, travelled under the name The Imperial Russian Ballet of St. Petersburg. The Imperial Russian Ballet gave more than seventy performances altogether during its tours of Finland, Sweden, Denmark and central Europe. The synchronic approach of the study covers the various cities as well as genres and thus stretches the rather rigid geographical and genre boundaries of dance historiography. The study also explores the role of the canon in dance history, revealing some of the diversity which underlies the standard canonical interpretation of early twentieth-century Russian ballet by bringing in source material from the archives of northern Europe. Issues like the central position of written documentation, the importance of geographical centres, the emphasis on novelty and reformers and the short and narrow scholarly tradition have affected the formation of the dance history canon in the west, often imposing limits on the historians and narrowing the scope of research. The analysis of the tours concentrates on four themes: virtuosity, character dancing, the idea of the expressive body, and the controversy over ballet and new dance. The debate concerning the old and new within ballet is also touched upon. These issues are discussed in connection with each city, but are stressed differently depending on the local art scene. In Copenhagen, the strong local canon based on August Bournonville s works influenced the Danish criticism of Russian ballet. In Helsinki, Stockholm and Berlin, the lack of a solid local canon made critics and audiences more open to new influences, and ballet was discussed in a much broader cultural context than that provided by the local ballet tradition. The contemporary interest in the more natural, expressive human body, emerging both in theatre and dance, was an international trend that also influenced the way ballet was discussed. Character dancing, now at low ebb, played a central role in the success of the Imperial Russian Ballet, not only because of its exoticism but also because it was considered to echo the kind of performing body represented by new dance forms. By exploring this genre and its dancers, the thesis brings to light artists who are less known in the current dance history canon, but who made considerable careers in their own time.
Resumo:
Regardless of the existence of antibiotics, infectious diseases are the leading causes of death in the world. Staphylococci cause many infections of varying severity, although they can also exist peacefully in many parts of the human body. Most often Staphylococcus aureus colonises the nose, and that colonisation is considered to be a risk factor for spread of this bacterium. S. aureus is considered to be the most important Staphylococcus species. It poses a challenge to the field of medicine, and one of the most problematic aspects is the drastic increase of the methicillin-resistant S. aureus (MRSA) strains in hospitals and community world-wide, including Finland. In addition, most of the clinical coagulase-negative staphylococcus (CNS) isolates express resistance to methicillin. Methicillin-resistance in S. aureus is caused by the mecA gene that encodes an extra penicillin-binding protein (PBP) 2a. The mecA gene is found in a mobile genomic island called staphylococcal chromosome cassette mec (SCCmec). The SCCmec consists of the mec gene and cassette chromosome recombinase (ccr)gene complexes. The areas of the SCCmec element outside the ccr and mec complex are known as the junkyard J regions. So far, eight types of SCCmec(SCCmec I- SCCmec VIII) and a number of variants have been described. The SCCmec island is an acquired element in S. aureus. Lately, it appears that CNS might be the storage place of the SCCmec that aid the S. aureus by providing it with the resistant elements. The SCCmec is known to exist only in the staphylococci. The aim of the present study was to investigate the horizontal transfer of SCCmec between the S. aureus and CNS. One specific aim was to study whether or not some methicillin-sensitive S. aureus (MSSA) strains are more inclined to receive the SCCmec than others. This was done by comparing the genetic background of clinical MSSA isolates in the health care facilities of the Helsinki and Uusimaa Hospital District in 2001 to the representatives of the epidemic MRSA (EMRSA) genotypes, which have been encountered in Finland during 1992-2004. Majority of the clinical MSSA strains were related to the EMRSA strains. This finding suggests that horizontal transfer of SCCmec from unknown donor(s) to several MSSA background genotypes has occurred in Finland. The molecular characteristics of representative clinical methicillin-resistant S. epidermidis (MRSE) isolates recovered in Finnish hospitals between 1990 and 1998 were also studied, examining their genetic relation to each other and to the internationally recognised MRSE clones as well, so as to ascertain the common traits between the SCCmec elements in MRSE and MRSA. The clinical MRSE strains were genetically related to each other; eleven PFGE types were associated with sequence type ST2 that has been identified world-wide. A single MRSE strain may possess two SCCmec types III and IV, which were recognised among the MRSA strains. Moreover, six months after the onset of an outbreak of MRSA possessing a SCCmec type V in a long-term care facility in Northern Finland (LTCF) in 2003, the SCCmec element of nasally carried methicillin-resistant staphylococci was studied. Among the residents of a LTCF, nasal carriage of MR-CNS was common with extreme diversity of SCCmec types. MRSE was the most prevalent CNS species. Horizontal transfer of SCCmec elements is speculated to be based on the sharing of SCCmec type V between MRSA and MRSE in the same person. Additionally, the SCCmec element of the clinical human S. sciuri isolates was studied. Some of the SCCmec regions were present in S. sciuri and the pls gene was common in it. This finding supports the hypothesis of genetic exchange happening between staphylococcal species. Evaluation of the epidemiology of methicillin-resistant staphylococcal colonisation is necessary in order to understand the apparent emergence of these strains and to develop appropriate control strategies. SCCmec typing is essential for understanding the emergence of MRSA strains from CNS, considering that the MR-CNS may represent the gene pool for the continuous creation of new SCCmec types from which MRSA might originate.
Resumo:
Breast cancer is the most common cancer in women in the western countries. Approximately two-thirds of breast cancer tumours are hormone dependent, requiring estrogens to grow. Estrogens are formed in the human body via a multistep route starting from cholesterol. The final steps in the biosynthesis include the CYP450 aromatase enzyme, converting the male hormones androgens (preferred substrate androstenedione ASD) into estrogens(estrone E1), and the 17beta-HSD1 enzyme, converting the biologically less active E1 into the active hormone 17beta-hydroxyestradiol E2. E2 is bound to the nuclear estrogen receptors causing a cascade of biochemical reactions leading to cell proliferation in normal tissue, and to tumour growth in cancer tissue. Aromatase and 17beta-HSD1 are expressed in or near the breast tumour, locally providing the tissue with estrogens. One approach in treating hormone dependent breast tumours is to block the local estrogen production by inhibiting these two enzymes. Aromatase inhibitors are already on the market in treating breast cancer, despite the lack of an experimentally solved structure. The structure of 17beta-HSD1, on the other hand, has been solved, but no commercial drugs have emerged from the drug discovery projects reported in the literature. Computer-assisted molecular modelling is an invaluable tool in modern drug design projects. Modelling techniques can be used to generate a model of the target protein and to design novel inhibitors for them even if the target protein structure is unknown. Molecular modelling has applications in predicting the activities of theoretical inhibitors and in finding possible active inhibitors from a compound database. Inhibitor binding at atomic level can also be studied with molecular modelling. To clarify the interactions between the aromatase enzyme and its substrate and inhibitors, we generated a homology model based on a mammalian CYP450 enzyme, rabbit progesterone 21-hydroxylase CYP2C5. The model was carefully validated using molecular dynamics simulations (MDS) with and without the natural substrate ASD. Binding orientation of the inhibitors was based on the hypothesis that the inhibitors coordinate to the heme iron, and were studied using MDS. The inhibitors were dietary phytoestrogens, which have been shown to reduce the risk for breast cancer. To further validate the model, the interactions of a commercial breast cancer drug were studied with MDS and ligand–protein docking. In the case of 17beta-HSD1, a 3D QSAR model was generated on the basis of MDS of an enzyme complex with active inhibitor and ligand–protein docking, employing a compound library synthesised in our laboratory. Furthermore, four pharmacophore hypotheses with and without a bound substrate or an inhibitor were developed and used in screening a commercial database of drug-like compounds. The homology model of aromatase showed stable behaviour in MDS and was capable of explaining most of the results from mutagenesis studies. We were able to identify the active site residues contributing to the inhibitor binding, and explain differences in coordination geometry corresponding to the inhibitory activity. Interactions between the inhibitors and aromatase were in agreement with the mutagenesis studies reported for aromatase. Simulations of 17beta-HSD1 with inhibitors revealed an inhibitor binding mode with hydrogen bond interactions previously not reported, and a hydrophobic pocket capable of accommodating a bulky side chain. Pharmacophore hypothesis generation, followed by virtual screening, was able to identify several compounds that can be used in lead compound generation. The visualisation of the interaction fields from the QSAR model and the pharmacophores provided us with novel ideas for inhibitor development in our drug discovery project.
Resumo:
Portable music players have made it possible to listen to a personal collection of music in almost every situation, and they are often used during some activity to provide a stimulating audio environment. Studies have demonstrated the effects of music on the human body and mind, indicating that selecting music according to situation can, besides making the situation more enjoyable, also make humans perform better. For example, music can boost performance during physical exercises, alleviate stress and positively affect learning. We believe that people intuitively select different types of music for different situations. Based on this hypothesis, we propose a portable music player, AndroMedia, designed to provide personalised music recommendations using the user’s current context and listening habits together with other user’s situational listening patterns. We have developed a prototype that consists of a central server and a PDA client. The client uses Bluetooth sensors to acquire context information and logs user interaction to infer implicit user feedback. The user interface also allows the user to give explicit feedback. Large user interface elements facilitate touch-based usage in busy environments. The prototype provides the necessary framework for using the collected information together with other user’s listening history in a context- enhanced collaborative filtering algorithm to generate context-sensitive recommendations. The current implementation is limited to using traditional collaborative filtering algorithms. We outline the techniques required to create context-aware recommendations and present a survey on mobile context-aware music recommenders found in literature. As opposed to the explored systems, AndroMedia utilises other users’ listening habits when suggesting tunes, and does not require any laborious set up processes.
Resumo:
Background: As the human body ages, the arteries gradually lose their elasticity and become stiffer. Although inevitable, this process is influenced by hereditary and environmental factors. Interestingly, many classic cardiovascular risk factors affect the arterial stiffness. During the last decade, accelerated arterial stiffening has been recognized as an important cardiovascular risk factor associated with increased mortality as well as with several chronic disorders. Objectives: This thesis examines the role of arterial stiffness in relation to variations in a physiological feature in healthy individuals. In addition, the effect on arterial stiffness of an acute transitory disease and the effect of a chronic disease are studied. Furthermore, the thesis analyzes the prognostic value of a marker of arterial stiffness in individuals with chronic disease. Finally, a potential method of reducing arterial stiffness is evaluated. Material and study design: The first study examines pulse wave reflection and pulse wave velocity in relation to muscle fibre distribution in healthy middle-aged men. In the second study, pulse wave reflection in women with current or previous preeclampsia is compared to a healthy control group. The effect of aging on the different blood pressure indices in patients with type 1 diabetes is examined in the third study, whereas the fourth paper studies the relation between these blood pressure indices and mortality in type 2 diabetes. The fifth study evaluates how intake of a fermented milk product containing bioactive peptides affects pulse wave reflection in individuals with mild hypertension. Results and conclusions: Muscle fibre type distribution is not an independent determinant of arterial stiffness in middle-aged males. Pulse wave reflection is increased in pregnant women with preeclampsia, but not in previously preeclamptic non-pregnant women. Patients with type 1 diabetes have a higher and more rapidly increasing pulse pressure, which suggests accelerated arterial stiffening. In elderly type 2 diabetic patients, very high and very low levels of pulse pressure are associated with higher mortality. Intake of milk-derived bioactive peptides reduces pulse wave reflection in hypertensive males but not in hypertensive females.
Resumo:
This thesis is a study of the x-ray scattering properties of tissues and tumours of the breast. Clinical radiography is based on the absorption of the x-rays when passing right through the human body and gives information about the densities of the tissues. Besides being absorbed, x-rays may change their direction within the tissues due to elastic scattering or even to refraction. The phenomenon of scattering is a nuisance to radiography in general, and to mammography in particular, because it reduces the quality of the images. However, scattered x-rays bear very useful information about the structure of the tissues at the supra-molecular level. Some pathologies, like breast cancer, produce alterations to the structures of the tissues, being especially evident in collagen-rich tissues. On the other hand, the change of direction due to refraction of the x-rays on the tissue boundaries can be mapped. The diffraction enhanced imaging (DEI) technique uses a perfect crystal to convert the angular deviations of the x-rays into intensity variations, which can be recorded as images. This technique is of especial interest in the cases were the densities of the tissues are very similar (like in mammography) and the absorption images do not offer enough contrast. This thesis explores the structural differences existing in healthy and pathological collagen in breast tissue samples by the small-angle x-ray scattering (SAXS) technique and compares these differences with the morphological information found in the DEI images and the histo-pathology of the same samples. Several breast tissue samples were studied by SAXS technique in the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. Scattering patterns of the different tissues of the breast were acquired and compared with the histology of the samples. The scattering signals from adipose tissue (fat), connective tissue (collagen) and necrotic tissue were identified. Moreover, a clear distinction could be done between the scattering signals from healthy collagen and from collagen from an invasive tumour. Scattering from collagen is very characteristic. It includes several scattering peaks and scattering features that carry information about the size and the spacing of the collagen fibrils in the tissues. It was found that the collagen fibrils in invaded tumours were thinner and had a d-spacing length 0,7% longer that fibrils from healthy tumours. The scattering signals from the breast tissues were compared with the histology by building colour-coded maps across the samples. They were also imaged with the DEI technique. There was a total agreement between the scattering maps, the morphological features seen in the images and the information of the histo- pathological examination. The thesis demonstrates that the x-ray scattering signal can be used to characterize tissues and that it carries important information about the pathological state of the breast tissues, thus showing the potential of the SAXS technique as a possible diagnostic tool for breast cancer.
Resumo:
"Body and Iron: Essays on the Socialness of Objects" focuses on the bodily-material interaction of human subjects and technical objects. It poses a question, how is it possible that objects have an impact on their human users and examines the preconditions of active efficacy of objects. In this theoretical task the work relies on various discussions drawing from realistic ontology, phenomenology of body, neurophysiology of Antonio Damasio and psychoanalysis to establish both objects and bodies as material entities related in a causal interaction with each other. Out of material interaction emerge a symbolic field, psyche and culture that produce representations of interactions with material world they remain dependent on and conditioned by. Interaction with objects informs the human body via its somatosensory systems: interoseptive and proprioseptive (or kinesthetic) systems provide information to central nervous system of the internal state of the body and muscle tensions and motor activity of the limbs. Capability to control the movements of one's body by the internal "feel" of being a body turns out to be a precondition to the ability to control artificial extensions of the body. Motor activity of the body is involved in every perception of environment as the feel of one's own body is constitutive of any perception of external objects. Perception of an object cause changes in the internal milieu of the body and these changes in the organism form a bodily representation of an external object. Via these "muscle images" the subject can develop a feel for an instrument. Bodily feel for an object is pre-conceptual, practical knowledge that resists articulation but allows sensing the world through the object. This is what I would call sensual knowledge. Technical objects intervene between body and environment, transforming the relation of perception and motor activity. Once connected to a vehicle, human subject has to calibrate visual information of his or her position and movement in space to the bodily actions controlling the machine. It is the machine that mediates the relation of human actions to the relation of her body to its environment. Learning to use the machine necessarily means adjusting his or her bodily actions to the responses of the machine in relation to environmental changes it causes. Responsiveness of the machine to human touch "teaches" its subject by providing feedback of the "correctitude" of his or her bodily actions. Correct actions form a body technique of handling the object. This is the way of socialness of objects. While responding to human actions they generate their subjects. Learning to handle a machine means accepting the position of the user in the program of action materialized in the construction of the object. Objects mediate, channel and transform the relation of the body to its environment and via environment to the body itself according to their material and technical construction. Objects are sensory media: they channel signals and information from the environment thus constituting a representation of environment, a virtual or artificial reality. They also feed the body directly with their powers equipping their user with means of regulating somatic and psychic states of her self. For these reasons humans look for the company of objects. Keywords: material objects, material culture, sociology of technology, sociology of body, mobility, driving
Resumo:
This study examines how sex education is currently developed and implemented in Greek primary schools. The four publications that comprise it explore the following themes: (1) the position and visibility of sex education as one of the topics for health education programme development; (2) the inhibiting and enhancing factors in the development and implementation of primary school sex education programmes; (3) how issues of sex, sexuality, the human body and romantic relationships are visually and textually represented in primary school textbooks; (4) the impact of sex education on teachers and pupils; and (5) teachers experiences as practitioners who deal with sexuality- related issues at school. -- The research was based on conducting multiple sub-studies using a mixed-methods approach. Specifically, qualitative and quantitative data were collected and analysed. The initial quantitative data that had been obtained by questionnaire was followed by the collection and analysis of qualitative data. The qualitative data were acquired by way of examining one particular case, various texts, interviews with teachers and self-reflective material. The results of the sub-studies are presented in a more detailed manner in the study s four publications. -- In general, the sub-studies found that sex education as an educational activity occupies a marginal place within the instructional practices of Greek primary school teachers, since the subject is hardly mentioned in classroom material, such as textbooks. However, engaging in the provision of sex education programmes can become a meaningful and rewarding experience for many teachers as well as pupils and their families. Further, teachers classroom experiences pointed to school settings as sexualized environments. These contextual factors and conditions nevertheless affected teachers practices and perceptions on a personal and professional level.Health indicators in Greece provide a picture of a population that faces various sexual health related problems. However, as many studies (including this work) indicate, sex education programmes that meet specific standards can have a positive impact on students overall health and well-being. Sex education teaching has always been a controversial issue. Its successful implementation in Greece demands knowledgeable educators and responsible policy-makers. The findings of this study suggest that the content of Greek primary school textbooks needs to be revised in order to include texts and pictures that deal with the human body and human sexuality, encourage pupils to become involved in designing the content and methods of programmes and give teachers the opportunity to reflect on and discuss their experiences. Keywords: sex education, primary school, Greece
Resumo:
Microbes in natural and artificial environments as well as in the human body are a key part of the functional properties of these complex systems. The presence or absence of certain microbial taxa is a correlate of functional status like risk of disease or course of metabolic processes of a microbial community. As microbes are highly diverse and mostly notcultivable, molecular markers like gene sequences are a potential basis for detection and identification of key types. The goal of this thesis was to study molecular methods for identification of microbial DNA in order to develop a tool for analysis of environmental and clinical DNA samples. Particular emphasis was placed on specificity of detection which is a major challenge when analyzing complex microbial communities. The approach taken in this study was the application and optimization of enzymatic ligation of DNA probes coupled with microarray read-out for high-throughput microbial profiling. The results show that fungal phylotypes and human papillomavirus genotypes could be accurately identified from pools of PCR amplicons generated from purified sample DNA. Approximately 1 ng/μl of sample DNA was needed for representative PCR amplification as measured by comparisons between clone sequencing and microarray. A minimum of 0,25 amol/μl of PCR amplicons was detectable from amongst 5 ng/μl of background DNA, suggesting that the detection limit of the test comprising of ligation reaction followed by microarray read-out was approximately 0,04%. Detection from sample DNA directly was shown to be feasible with probes forming a circular molecule upon ligation followed by PCR amplification of the probe. In this approach, the minimum detectable relative amount of target genome was found to be 1% of all genomes in the sample as estimated from 454 deep sequencing results. Signal-to-noise of contact printed microarrays could be improved by using an internal microarray hybridization control oligonucleotide probe together with a computational algorithm. The algorithm was based on identification of a bias in the microarray data and correction of the bias as shown by simulated and real data. The results further suggest semiquantitative detection to be possible by ligation detection, allowing estimation of target abundance in a sample. However, in practise, comprehensive sequence information of full length rRNA genes is needed to support probe design with complex samples. This study shows that DNA microarray has the potential for an accurate microbial diagnostic platform to take advantage of increasing sequence data and to replace traditional, less efficient methods that still dominate routine testing in laboratories. The data suggests that ligation reaction based microarray assay can be optimized to a degree that allows good signal-tonoise and semiquantitative detection.
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Luce Irigaray is a Belgian-born philosopher, psychoanalyst and linguist. Irigaray s concept of woman is crucial for understanding her own work but also for examining and developing the theoretical and methodological basis of feminist theory. This thesis argues that, ultimately, Irigaray s exploration of woman s being challenges our traditional notion of philosophy as a neutral discourse and the traditional notion of ourselves as philosophizing persons or human beings. However, despite its crucial role, Irigaray s idea of woman still lacks a comprehensive explication. This is because the discourse of sexual difference is blurred by the ideas of essentialism and biologism. --- Irigaray s concept of woman has been interpreted and criticized from the perspectives of metaphysical essentialism, strategic essentialism, realist essentialism and deconstructionism. This thesis argues that a reinterpretation is necessary to account for Irigaray s claims about the the traditional woman , mimesis, the specificity of the feminine body, feminine expression and sexual difference. Moreover, any reading should account for the differences between women and avoid giving a prescriptive function to the essence of woman. --- My thesis develops a new interpretation of Irigaray s concept of woman on the basis of the phenomenology of the body. It argues that Irigaray s discourse on woman can and must be understood by an idea of existential style. Existential style is embodied, affective and spiritual and it is constituted in relation to oneself, to others and to the world. It is temporal, it evolves and changes but preserves its open unity in its transformations. Stylistic unities, such as femininity or philosophy, are constituted in and by the singulars. -- This study discusses and analyses feminine existential style as a central theme and topic of Irigaray s works and shows how her work operates as a primary and paradigmatic example of the feminine style. These tasks are performed by studying the mimetic positions available for women and by explicating the phenomenological background of Irigaray s conceptions of the philosophical method, and the lived, expressive and affective body. The critical occupation and transformation of these mimetic positions, the inquiry into the first-person pre-discursive experience, and the cultivation of feminine expressivity open up the possibility of becoming a woman writer, a woman lover and a woman philosopher. The appearance of these new feminine figures is a precondition for the realization of sexual difference. So Irigaray opens up the possibility of sexual difference by instituting and constituting a feminine subject of love and wisdom, and by problematizing the idea of a neutral and absolute subject.
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Humans are a social species with the internal capability to process social information from other humans. To understand others behavior and to react accordingly, it is necessary to infer their internal states, emotions and aims, which are conveyed by subtle nonverbal bodily cues such as postures, gestures, and facial expressions. This thesis investigates the brain functions underlying the processing of such social information. Studies I and II of this thesis explore the neural basis of perceiving pain from another person s facial expressions by means of functional magnetic resonance imaging (fMRI) and magnetoencephalography (MEG). In Study I, observing another s facial expression of pain activated the affective pain system (previously associated with self-experienced pain) in accordance with the intensity of the observed expression. The strength of the response in anterior insula was also linked to the observer s empathic abilities. The cortical processing of facial pain expressions advanced from the visual to temporal-lobe areas at similar latencies (around 300 500 ms) to those previously shown for emotional expressions such as fear or disgust. Study III shows that perceiving a yawning face is associated with middle and posterior STS activity, and the contagiousness of a yawn correlates negatively with amygdalar activity. Study IV explored the brain correlates of interpreting social interaction between two members of the same species, in this case human and canine. Observing interaction engaged brain activity in very similar manner for both species. Moreover, the body and object sensitive brain areas of dog experts differentiated interaction from noninteraction in both humans and dogs whereas in the control subjects, similar differentiation occurred only for humans. Finally, Study V shows the engagement of the brain area associated with biological motion when exposed to the sounds produced by a single human being walking. However, more complex pattern of activation, with the walking sounds of several persons, suggests that as the social situation becomes more complex so does the brain response. Taken together, these studies demonstrate the roles of distinct cortical and subcortical brain regions in the perception and sharing of others internal states via facial and bodily gestures, and the connection of brain responses to behavioral attributes.
Resumo:
Obesity increases the risk for several conditions, including type 2 diabetes mellitus, cardiovascular disease, hypertension, osteoarthirits and certain types of cancer. Twin- and family studies have shown that there is a major genetic component in the determination of body mass. In recent years several technological and scientific advance have been made in obesity research. For instance, novel replicated loci have been revealed by a number of genome wide association studies. This thesis aimed to investigate the association of genetic factors and obesity-related quantitative traits. The first study investigated the role of the lactase gene in anthropometric traits. We genetically defined lactose persistence by genotyping 31 720 individuals of European descent. We found that lactase persistence was significantly correlated with weight and body mass index but not with height. In the second study we performed the largest whole genome linkage scan for body mass index to date. The sample consisted of 4401 twin families and 10 535 individuals from six European countries. We found supporting evidence for two loci (3q29 and 7q36). We observed that the heritability estimate increased substantially when additional family members were removed from the analyses, which suggests reduced environmental variance in the twin sample. In the third study we assessed metabonomic, transcriptomic and genomic variation in a Finnish population cohort of 518 individuals. We formed gene expression networks to portray pathways and showed that a set of highly correlated genes of an inflammatory pathway associated with 80 serum metabolites (of 134 quantified measures). Strong association was found, for example, with several lipoprotein subclasses. We inferred causality by using genetic variation as anchors. The expression of the network genes was found to be dependent on the circulatory metabolite concentrations.