78 resultados para Early-Bronze pontic cultures

em Helda - Digital Repository of University of Helsinki


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This thesis addresses the following broad research question: what did it mean to be a disabled Revolutionary War veteran in the early United States during the period from 1776 to roughly 1840? The study approaches the question from two angles: a state-centred one and an experiential one. In both cases, the theoretical framework employed comes from disability studies. Consequently, disability is regarded as a sociocultural phenomenon rather than a medical condition. The state-centred dimension of the study explores the meaning of disability and disabled veterans to the early American state through an examination of the major military pension laws of the period. An analysis of this legislation, particularly the invalid pension acts of 1793 and 1806, indicates that the early United States represents a key period in the development of the modern disability category. The experiential approach, in contrast, shifts the focus of attention away from the state towards the lived experiences of disabled veterans. It seeks to address the issue of whether or not the disabilities of disabled veterans had any significant material impact on their everyday lives. It does this through a comparison of the situation of 153 disabled veterans with that of an equivalent number of nondisabled veterans. The former group received invalid pensions while the latter did not. In comparing the material conditions of disabled and nondisabled veterans, a wide range of primary sources from military records to memoirs and letters are used. The most important sources in this regard are the pension application papers submitted by veterans in the early nineteenth century. These provide us with a unique insight into the everyday lives of veterans. Looking at the issue of experience through the window of the pension files reveals that there was not much difference in the broad contours of disabled and nondisabled veteran life. This finding has implications for the theorisation of disability that are highlighted and discussed in the thesis. The main themes covered in this study are: the wartime experiences of injured American soldiers, the military pension establishment of the early United States and the legal construction of disability, and the post-war working and family lives of disabled veterans. Keywords: disability, early America, veterans, military pensions, disabled people, Revolutionary War, United States, disability theory.

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The equilibrium between cell proliferation, differentiation, and apoptosis is crucial for maintaining homeostasis in epithelial tissues. In order for the epithelium to function properly, individual cells must gain normal structural and functional polarity. The junctional proteins have an important role both in binding the cells together and in taking part in cell signaling. Cadherins form adherens junctions. Cadherins initiate the polarization process by first recognizing and binding the neighboring cells together, and then guiding the formation of tight junctions. Tight junctions form a barrier in dividing the plasma membranes to apical and basolateral membrane domains. In glandular tissues, single layered and polarized epithelium is folded into tubes or spheres, in which the basal side of the epithelial layer faces the outer basal membrane, and the apical side the lumen. In carcinogenesis, the differentiated architecture of an epithelial layer is disrupted. Filling of the luminal space is a hallmark of early epithelial tumors in tubular and glandular structures. In order for the transformed tumor cells to populate the lumen, enhanced proliferation as well as inhibition of apoptosis is required. Most advances in cancer biology have been achieved by using two-dimensional (2D) cell culture models, in which the cells are cultured on flat surfaces as monolayers. However, the 2D cultures are limited in their capacity to recapitulate the structural and functional features of tubular structures and to represent cell growth and differentiation in vivo. The development of three-dimensional (3D) cell culture methods enables the cells to grow and to be studied in a more natural environment. Despite the wide use of 2D cell culture models and the development of novel 3D culture methods, it is not clear how the change of the dimensionality of culture conditions alters the polarization and transformation process and the molecular mechanisms behind them. Src is a well-known oncogene. It is found in focal and adherens junctions of cultured cells. Active src disrupts cell-cell junctions and interferes with cell-matrix binding. It promotes cell motility and survival. Src transformation in 2D disrupts adherens junctions and the fibroblastic phenotype of the cells. In 3D, the adherens junctions are weakened, and in glandular structures, the lumen is filled with nonpolarized vital cells. Madin-Darby canine kidney (MDCK) cells are an epithelial cell type commonly used as a model for cell polarization. Its-src-transformed variants are useful model systems for analyzing the changes in cell morphology, and they play a role in src-induced malignant transformation. This study investigates src-transformed cells in 3D cell cultures as a model for malignant transformation. The following questions were posed. Firstly: What is the role of the composition and stiffness of the extracellular matrix (ECM) on the polarization and transformation of ts v-src MDCK cells in 3D cell cultures? Secondly: How do the culture conditions affect gene expression? What is the effect of v-src transformation in 2D and in 3D cell models? How does the shift from 2D to 3D affect cell polarity and gene expression? Thirdly: What is the role of survivin and its regulator phosphatase and tensin homolog protein (PTEN) in cell polarization and transformation, and in determining cell fate? How does their expression correlate with impaired mitochondrial function in transformed cells? In order to answer the above questions, novel methods of culturing and monitoring cells had to be created: novel 3D methods of culturing epithelial cells were engineered, enabling real time monitoring of a polarization and transformation process, and functional testing of 3D cell cultures. Novel 3D cell culture models and imaging techniques were created for the study. Attention was focused especially on confocal microscopy and live-cell imaging. Src-transformation disturbed the polarization of the epithelium by disrupting cell adhesion, and sensitized the cells to their environment. With active src, the morphology of the cell cluster depended on the composition and stiffness of the matrix. Gene expression studies revealed a broader impact of src transformation than mere continuous activity of src-kinase. In 2D cultures, src transformation altered the expression of immunological, actin cytoskeleton and extracellular matrix (ECM). In 3D, the genes regulating cell division, inhibition of apoptosis, cell metabolism, mitochondrial function, actin cytoskeleton and mechano-sensing proteins were altered. Surprisingly, changing the culture conditions from 2D to 3D affected also gene expression considerably. The microarray hit survivin, an inhibitor of apoptosis, played a crucial role in the survival and proliferation of src-transformed cells.

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Poor pharmacokinetics is one of the reasons for the withdrawal of drug candidates from clinical trials. There is an urgent need for investigating in vitro ADME (absorption, distribution, metabolism and excretion) properties and recognising unsuitable drug candidates as early as possible in the drug development process. Current throughput of in vitro ADME profiling is insufficient because effective new synthesis techniques, such as drug design in silico and combinatorial synthesis, have vastly increased the number of drug candidates. Assay technologies for larger sets of compounds than are currently feasible are critically needed. The first part of this work focused on the evaluation of cocktail strategy in studies of drug permeability and metabolic stability. N-in-one liquid chromatography-tandem mass spectrometry (LC/MS/MS) methods were developed and validated for the multiple component analysis of samples in cocktail experiments. Together, cocktail dosing and LC/MS/MS were found to form an effective tool for increasing throughput. First, cocktail dosing, i.e. the use of a mixture of many test compounds, was applied in permeability experiments with Caco-2 cell culture, which is a widely used in vitro model for small intestinal absorption. A cocktail of 7-10 reference compounds was successfully evaluated for standardization and routine testing of the performance of Caco-2 cell cultures. Secondly, cocktail strategy was used in metabolic stability studies of drugs with UGT isoenzymes, which are one of the most important phase II drug metabolizing enzymes. The study confirmed that the determination of intrinsic clearance (Clint) as a cocktail of seven substrates is possible. The LC/MS/MS methods that were developed were fast and reliable for the quantitative analysis of a heterogenous set of drugs from Caco-2 permeability experiments and the set of glucuronides from in vitro stability experiments. The performance of a new ionization technique, atmospheric pressure photoionization (APPI), was evaluated through comparison with electrospray ionization (ESI), where both techniques were used for the analysis of Caco-2 samples. Like ESI, also APPI proved to be a reliable technique for the analysis of Caco-2 samples and even more flexible than ESI because of the wider dynamic linear range. The second part of the experimental study focused on metabolite profiling. Different mass spectrometric instruments and commercially available software tools were investigated for profiling metabolites in urine and hepatocyte samples. All the instruments tested (triple quadrupole, quadrupole time-of-flight, ion trap) exhibited some good and some bad features in searching for and identifying of expected and non-expected metabolites. Although, current profiling software is helpful, it is still insufficient. Thus a time-consuming largely manual approach is still required for metabolite profiling from complex biological matrices.

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The subject of the study is the classical Latin concept 'mundus muliebris', usually translated simply as women’s toiletry items. The task of the research is, on one hand, to find a more accurate and comprehensive literary definition for the concept as used in the early Imperial period, and on the other, to examine whether it is possible to find corresponding groupings of material objects among the finds from Pompeian houses destroyed by the eruption of Mount Vesuvius in AD 79. The study is based on two different bodies of evidence, literary and material, and consequently uses two independent methods of research. In the philological part of the study, all occurrences of the concept 'mundus muliebris' in classical Latin texts were identified and analysed in their proper literary context, paying special attention to information about the nature of the objects included (name, owner, quantity, value, location in the house). On the basis of this analysis, mirrors were chosen as the key elements of the archaeological research, being ̶ hypothetically ̶ the most probable objects to be found among any extant 'mundus muliebris' contexts in Pompeian houses. In the archaeological part of the study, all mirrors deposited in the Archaeological Storerooms of Pompeii, mostly unpublished, were examined, together with their original find contexts. For more detailed documentation, classification, as well as quantitative and functional analysis, the fifty-nine best preserved household or shop contexts were chosen. Among these contexts, only a few ‘ideal’ groups closely corresponding to the literary definitions were found. However, in most cases a functional artifact pattern of toiletry items could indeed be found grouped together with the mirror. The arrangement of the contexts in the domestic space also revealed a clear pattern. Firstly, the contexts consistently seem to be found in the place of storage, inside locked boxes, not in the place of use. Secondly, they show that for the storage of such objects small closed rooms flanking the main entrance of the house were preferred. Culturally, 'mundus muliebris' can be described as a very complex multi-layered concept intimately interrelated with the female gender, an instrument of its bodily creation and a symbol of its nature. Concretely, it has at its core mirrors and instruments for the care of skin and hair, and includes, in more technical definitions, washing equipment as well. In the Roman domus, lacking specific women’s quarters, this box containing toiletries and other personal objects could be defined as the true, although mobile, private space of the household’s female members.

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Bertrand Russell (1872 1970) introduced the English-speaking philosophical world to modern, mathematical logic and foundational study of mathematics. The present study concerns the conception of logic that underlies his early logicist philosophy of mathematics, formulated in The Principles of Mathematics (1903). In 1967, Jean van Heijenoort published a paper, Logic as Language and Logic as Calculus, in which he argued that the early development of modern logic (roughly the period 1879 1930) can be understood, when considered in the light of a distinction between two essentially different perspectives on logic. According to the view of logic as language, logic constitutes the general framework for all rational discourse, or meaningful use of language, whereas the conception of logic as calculus regards logic more as a symbolism which is subject to reinterpretation. The calculus-view paves the way for systematic metatheory, where logic itself becomes a subject of mathematical study (model-theory). Several scholars have interpreted Russell s views on logic with the help of the interpretative tool introduced by van Heijenoort,. They have commonly argued that Russell s is a clear-cut case of the view of logic as language. In the present study a detailed reconstruction of the view and its implications is provided, and it is argued that the interpretation is seriously misleading as to what he really thought about logic. I argue that Russell s conception is best understood by setting it in its proper philosophical context. This is constituted by Immanuel Kant s theory of mathematics. Kant had argued that purely conceptual thought basically, the logical forms recognised in Aristotelian logic cannot capture the content of mathematical judgments and reasonings. Mathematical cognition is not grounded in logic but in space and time as the pure forms of intuition. As against this view, Russell argued that once logic is developed into a proper tool which can be applied to mathematical theories, Kant s views turn out to be completely wrong. In the present work the view is defended that Russell s logicist philosophy of mathematics, or the view that mathematics is really only logic, is based on what I term the Bolzanian account of logic . According to this conception, (i) the distinction between form and content is not explanatory in logic; (ii) the propositions of logic have genuine content; (iii) this content is conferred upon them by special entities, logical constants . The Bolzanian account, it is argued, is both historically important and throws genuine light on Russell s conception of logic.

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The study is an examination of how the distant national past has been conceived and constructed for Finland from the mid-sixteenth century to the Second World War. The author argues that the perception and need of a national 'Golden Age' has undergone several phases during this period, yet the perceived Greatness of the Ancient Finns has been of great importance for the growth and development of the fundamental concepts of Finnish nationalism. It is a question reaching deeper than simply discussing the Kalevala or the Karelianism of the 1890s. Despite early occurrences of most of the topics the image-makers could utilize for the construction of an Ancient Greatness, a truly national proto-history only became a necessity after 1809, when a new conceptual 'Finnishness' was both conceived and brought forth in reality. In this process of nation-building, ethnic myths of origin and descent provided the core of the nationalist cause - the defence of a primordial national character - and within a few decades the antiquarian issue became a standard element of the nationalist public enlightenment. The emerging, archaeologically substantiated, nationhood was more than a scholarly construction: it was a 'politically correct' form of ethnic self-imaging, continuously adapting its message to contemporary society and modern progress. Prehistoric and medieval Finnishness became even more relevant for the intellectual defence of the nation during the period of Russian administrative pressure 1890-1905. With independence the origins of Finnishness were militarized even further, although the 'hot' phase of antiquarian nationalism ended, as many considered the Finnish state reestablished after centuries of 'dependency'. Nevertheless, the distant past of tribal Finnishness and the conceived Golden Age of the Kalevala remained obligating. The decline of public archaeology is quite evident after 1918, even though the national message of the antiquarian pursuits remained present in the history culture of the public. The myths, symbols, images, and constructs of ancient Finnishness had already become embedded in society by the turn of the century, like the patalakki cap, which remains a symbol of Finnishness to this day. The method of approach is one of combining a broad spectrum of previously neglected primary sources, all related to history culture and the subtle banalization of the distant past: school books, postcards, illustrations, festive costumes, drama, satirical magazines, novels, jewellery, and calendars. Tracing the origins of the national myths to their original contexts enables a rather thorough deconstruction of the proto-historical imaginary in this Finnish case study. Considering Anthony D. Smith's idea of ancient 'ethnies' being the basis for nationalist causes, the author considers such an approach in the Finnish case totally misplaced.

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According to the models conceptualizing work stress, increased risk of health problems arise when high job demands co-occur with low job control (the demand-control model) or the efforts invested by the employee are disproportionately high compared to the rewards received (effort-reward imbalance model). This study examined the association between work stress and early atherosclerosis with particular attention to the role of pre-employment risk factors and genetic background in this association. The subjects were young healthy adults aged 24-39 who were participating in the 21-year follow-up of the ongoing prospective "Cardiovascular Risk in Young Finns" study in 2001-2002. Work stress was evaluated with questionnaires on demand-control model and on effort-reward model. Atherosclerosis was assessed with ultrasound of carotid artery intima-media thickness (IMT). In addition, risk for enhanced atherosclerotic process was assessed by measuring with heart rate variability and heart rate. Pre-employment risk factors, measured at age 12 to 18, included such as body mass index, blood lipids, family history of coronary heart disease, and parental socioeconomic position. Variants of the neuregulin-1 were determined using genomic DNA. The results showed that higher work stress was associated with higher IMT in men. This association was not attenuated by traditional risk factors of atherosclerosis and coronary heart disease or by pre-employment risk factors measured in adolescence. Neuregulin-1 gene moderated the association between work stress and IMT in men. A significant association between work stress and IMT was found only for the T/T genotype of the neuregulin-1 gene but not for other genotypes. Among women an association was found between higher work stress and lower heart rate variability, suggesting higher risk for developing atherosclerosis. These associations could not be explained by demographic characteristics or coronary risk factors. The present findings provide evidence for an association between work stress and atherosclerosis in relatively young population. This association seems to be modified by genetic influences but it does not appear to be confounded by pre-employment adolescent risk factors.

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The success of entering work life, young people s psychological resources and self-reported well-being were studied in a longitudinal setting from a life-span developmental-contextual perspective in early adulthood. The aim was to analyse how psychosocial characteristics in early childhood and adolescence predict successful entrance into work life, how this is associated with well-being, and to assess the level of psychological resources such as dispositional optimism, personal meaning of work and coping in early adulthood. The role of these and social support, in the relationship between regional factors (such as place of residence and migration), self-reported health and life satisfaction was studied. The association between a specific coping strategy, i.e. eating and drinking in a stressful situation and eating habits, was studied to demonstrate how coping is associated with health behaviour. Multivariate methods, including binary logistic regression analyses and ANOVA, were used for statistical analyses. The subjects were members of the Northern Finland 1966 Birth Cohort, which consists of all women and men born in 1966 in the two northernmost provinces of Finland (n= 12,058). The most recent follow-up, at the age of 31 years when 11,637 subjects were alive, took place in 1997-1998. The results show, first, that social resources in the childhood family and adolescence school achievement predict entrance into the labour market. Secondly, psychosocial resources were found to mediate the relationship between migration from rural to urban areas, and subjective well-being. Thirdly, psychological resources at entrance into the labour market were found to develop from early infancy on. They are, however, influenced later by work history. Fourthly, stress-related eating and drinking, as a way of coping, was found to be directly associated with unhealthy eating habits and alcohol use. Gender differences were found in psychosocial resources predicting, and being associated with success in entering the labour market. For men, the role of attitudinal and psychological factors seems to be especially important in entrance into work life and in the development of psychological resources. For women, academic attainment was more important for successfully entering work life, and lack of emotional social support was a risk factor for stress-related eating only among women. Stress-related eating and drinking habits were predicted by a long history of unemployment as well as a low level of education among both genders, but not excluding an academic degree among men. The results emphasize the role of childhood psychosocial factors in preventing long-term unemployment and in enhancing psychological well-being in early adulthood. Success in entering work life, in terms of continuous work history, plays a crucial role for well-being and the amount of psychological resources in early adulthood. The results emphasize the crucial role of enhancing psychological resources for promoting positive health behaviour and diminishing regional differences in subjective well-being.

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Work stress is after musculoskeletal disorders the second most common work-related health problem in the European Union, affecting 28% of EU employees. Furthermore, a 50% excessive cardiovascular disease risk among employees with work stress is reported. High job demands combined with low job control according to the Job Demands-Job Control model, or high effort combined with low rewards according to Effort-Reward Imbalance model, are likely to produce work stress in the majority of employees. Atherosclerotic wall thickening is a validated marker of an increased risk of cardiovascular disease. This study examined the role of childhood and adolescent factors as antecedents of work stress and early atherosclerosis, and in the relationship between them. The Cardiovascular Risk in Young Finns Study, (the CRYF project) started in 1980 when the participants were at the age of three to 18 years. Follow-ups have been conducted every three years until 1992, after that in 1997 and 2001, and the latest is ongoing in 2008. The participants parents reported their socioeconomic position in 1980 and 1983, and their life satisfaction in 1983. Biological risk factors were measured in 1980 and 2001. Type A behaviour was reported in 1986, 1989 and 2001. In the 2001 follow-up when the participants were aged 24 to 39, work stress was assessed from responses to questionnaires on job demands-job control and effort-reward imbalance, and education. Ultrasound measurement of the carotid intima-media thickness (CIMT) was used to assess atherosclerosis. There were 755, 746, 1014 and 494 participants in studies I-IV, respectively. The results showed that low parental socioeconomic position and parental life dissatisfaction during childhood and adolescence predicted higher levels of job strain 18 years later, and that education mediated the relationship between parental socioeconomic position and job strain. Childhood and adolescent family factors were not related to the effort-reward imbalance. Parental life satisfaction was associated with high rewards at work among the men, and high parental socioeconomic position was associated with high reward among the women. Among the men, the eagerness-energy component of Type A behaviour across different developmental periods predicted increased CIMT. Among the women, hard-driving component of Type A behaviour predicted decreased CIMT. Low leadership characteristic in adolescence and early adulthood was associated with both high job strain and increased CIMT, and attenuated the relationship between job strain and CIMT to non-significance in men. The current findings add to the literature on the relationship between job strain and health literature in adopting a developmental perspective. The results imply that work stress does not completely originate from work. There are childhood and adolescent environmental and dispositional effects on work stress and CIMT several years later, and these partly seem to operate through educational attainment.

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The aim was to analyse the growth and compositional development of the receptive and expressive lexicons between the ages 0,9 and 2;0 in the full-term (FT) and the very-low-birth-weight (VLBW) children who are acquiring Finnish. The associations between the expressive lexicon and grammar at 1;6 and 2;0 in the FT children were also studied. In addition, the language skills of the VLBW children at 2;0 were analysed, as well as the predictive value of early lexicon to the later language performance. Four groups took part in the studies: the longitudinal (N = 35) and cross-sectional (N = 146) samples of the FT children, and the longitudinal (N = 32) and cross-sectional (N = 66) samples of VLBW children. The data was gathered by applying of the structured parental rating method (the Finnish version of the Communicative Development Inventory), through analysis of the children´s spontaneous speech and by administering a a formal test (Reynell Developmental Language Scales). The FT children acquired their receptive lexicons earlier, at a faster rate and with larger individual variation than their expressive lexicons. The acquisition rate of the expressive lexicon increased from slow to faster in most children (91%). Highly parallel developmental paths for lexical semantic categories were detected in the receptive and expressive lexicons of the Finnish children when they were analysed in relation to the growth of the lexicon size, as described in the literature for children acquiring other languages. The emergence of grammar was closely associated with expressive lexical growth. The VLBW children acquired their receptive lexicons at a slower rate and had weaker language skills at 2;0 than the full-term children. The compositional development of both lexicons happened at a slower rate in the VLBW children when compared to the FT controls. However, when the compositional development was analysed in relation to the growth of lexicon size, this development occurred qualitatively in a nearly parallel manner in the VLBW children as in the FT children. Early receptive and expressive lexicon sizes were significantly associated with later language skills in both groups. The effect of the background variables (gender, length of the mother s basic education, birth weight) on the language development in the FT and the VLBW children differed. The results provide new information of early language acquisition by the Finnish FT and VLBW children. The results support the view that the early acquisition of the semantic lexical categories is related to lexicon growth. The current findings also propose that the early grammatical acquisition is closely related to the growth of expressive vocabulary size. The language development of the VLBW children should be followed in clinical work.

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The main idea of this study was to find out how immigrants understand and define successful co-operation and professional partnership in early childhood education. Another target of this research was to think over how the parents see professional partnership from their viewpoint, and how willing / ready the they are in engaging in the professional partnership with the day care personnel. The theoretical part of this research is based on theories of immigration and theories of it s different forms, theories of cultural varieties and theory of modernizing co-operation through using professional partnership. Also guidelines and policies for day care and early childhood education play a part in the theory section. Theory part is written to support research problems. The research method used in this study is peer interview. The interviewed are both immigrants and customers of day care services. The data collected is comprised of materials from peer interviews and personal background information. The interviewed were of Somalia and Russian ethnic groups. Interview were carried out in each group in the participants own mother tongue. These peer interviews showed that parents were interested and willing to discuss professional partnership. From this research one can conclude that the term professional partnership is seen as a complex term, and as a term difficult to understand. From the results it is seen that quite often the principles of professional partnership are not carried out in practise. According to the material gathered, the parents feel that lack of common language and prejudice against immigrants effectively prevents the professional partnership from being formed. The cultural differences can become challenging in a professional partnership. Based on this research, one can conclude that when different cultures meet, there has to be mutual will to understand and to be understood in order to make sure that the children s development, both educational and physical, is supported in a best possible way.

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The genus Actinomyces consists of a heterogeneous group of gram-positive, mainly facultatively anaerobic or microaerobic rods showing various degrees of branching. In the oral cavity, streptococci and Actinomyces form a fundamental component of the indigenous microbiota, being among initial colonizers in polymicrobial biofilms. The significance of the genus Actinomyces is based on the capability of species to adhere to surfaces such as on teeth and to co-aggregate with other bacteria. Identification of Actinomyces species has mainly been based on only a few biochemical characteristics, such as pigmentation and catalase production, or on the use of a single commercial kit. The limited identification of oral Actinomyces isolates to species level has hampered knowledge of their role both in health and disease. In recent years, Actinomyces and related organisms have attracted the attention of clinical microbiologists because of a growing awareness of their presence in clinical specimens and their association with disease. This series of studies aimed to amplify the identification methods for Actinomyces species. With the newly developed identification scheme, the age-related occurrence of Actinomyces in healthy mouths of infants and their distribution in failed dental implants was investigated. Adhesion of Actinomyces species to titanium surfaces processed in various ways was studied in vitro. The results of phenotypic identification methods indicated a relatively low applicability of commercially available test kits for reliable identification within the genus Actinomyces. However, in the study of conventional phenotypic methods, it was possible to develop an identification scheme that resulted in accurate differentiation of Actinomyces and closely related species, using various different test methods. Genotypic methods based on 16S rRNA sequence analysis of Actinomyces proved to be a useful method for genus level identification and further clarified the species level identification with phenotypic methods. The results of the study of infants showed that the isolation frequency of salivary Actinomyces species increased according to age: thirty-one percent of the infants at 2 months but 97% at 2 years of age were positive for Actinomyces. A. odontolyticus was the most prominent Actinomyces colonizer during the study period followed in frequency by A. naeslundii and A. viscosus. In the study of explanted dental implants, Actinomyces was the most prevalent bacterial genus, colonizing 94% of the fixtures. Also in the implants A. odontolyticus was revealed as the most common Actinomyces species. It was present in 84% of Actinomyces -positive fixtures followed in frequency by A. naeslundii, A. viscosus and A. israelii. In an in vitro study of titanium surfaces, different Actinomyces species showed variation regarding their adhesion to titanium. Surface roughness as well as albumin coating of titanium had significant effects on adhesion. The use of improved phenotypic and molecular diagnostic methods increased the accuracy of the identification of the Actinomyces to species level. This facilitated an investigation of their occurrence and distribution in oral specimens in both health and disease.

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Varhaislapsuuden karies ja sen ehkäisy kehittyvän terveydenhuollon maassa Varhaislapsuuden karies on merkittävä kansanterveysongelma varsinkin lapsirikkaissa maissa ja väestöissä. Karieksen hoitaminen vie paljon voimavaroja ja aiheuttaa mittavia taloudellisia seuraamuksia. Karies voi ilmaantua lapselle jo vauvaikäisenä, pian ensimmäisten maitohampaiden puhjettua suuhun. Alle 3-vuotiaiden karieksesta on kuitenkin niukasti tilastotietoja. Maailman terveysjärjestökin suosittaa tietojen keräämistä vasta 3-vuotiaiden ikäryhmästä. Heistä kariesta sairastaa Suomessa 16 %, Yhdysvalloissa 25 %, Englannissa 30 %, Iranissa 46 % ja Saudi-Arabiassa 61 %. Tämä väitöstutkimus selvitti karieksen esiintymistä ja sen vaaratekijöitä 1─3-vuotiailla Teheranissa. Lisäksi tutkimus arvioi perusterveydenhuoltoon sisällytetyn karieksen ehkäisyn tuloksellisuutta. Tutkimuskohteiksi arvottiin Teheranista 18 neuvolaa. Jokaisessa oltiin 4 päivää, jolloin kaikkia rokotuksiin tulleita 1─3-vuotiaita äiteineen pyydettiin osallistumaan tutkimukseen. Kahta lukuun ottamatta kaikki äidit suostuivat, ja aineistoon tuli kaikkiaan 504 lasta äiteineen. Kaikki 1-vuotiaat, 242 lasta äiteineen, valittiin karieksen ehkäisykokeiluun. Sitä varten neuvolat jaettiin kolmeen ryhmään, joista kaksi (A ja B) oli koeryhmiä ja yksi (C) oli vertailuryhmä. Tutkimus alkoi äidin haastattelulla. Siinä selvitettiin perheen koulutus- ja tulotaso sekä lapsen ruokinnasta imetyksen kesto, yösyötöt ja päiväaikaan nautitut makeat. Vielä kysyttiin lapsen ja äidin suuhygieniatavoista ja äidin kokemuksista lapsen suun puhdistamisessa. Sitten hammaslääkäri tutki lapsen suun ja kirjasi karieksen ja hammasplakin esiintymät. Suun tutkimuksen jälkeen äiti ja lapsi siirtyivät rokotushuoneeseen. Koeryhmissä (A ja B) äidit saivat terveydenhoitajalta suunterveyttä koskevan esitteen ja kehotuksen lukea se huolellisesti. Lisäksi ryhmässä A terveydenhoitaja kertoi suun ja hampaiden terveydenhoidosta saman esitteen avulla, ja neuvolan henkilökunta muistutti suunhoidon tärkeydestä puhelimitse kahdesti seuraavan puolen vuoden kuluessa. Vertailuryhmässä äideille ei annettu suunhoidon ohjeita. Kaikissa ryhmissä äitejä muistutettiin seuraavan rokotuskerran ajankohdasta, muttei mainittu tulevaa toista hammastarkastusta. Varhaislapsuuden kariesta sairasti ikäryhmästä riippuen 3─26 % tutkituista 1─3-vuotiaista, ja 65─76 %:lla oli hammasplakkia. Äideistä 68 % harjasi hampaansa päivittäin ja 39 % puhdisti lapsensa suun päivittäin. Mitä useammin äiti harjasi omat hampaansa, sitä paremmin hän huolehti lapsen suun puhtaudesta. Rintaruokinta oli yleistä eikä lisännyt kariesvaaraa. Yöllä pullomaitoa saavilla karies oli 5 kertaa yleisempää kuin muilla. Neuvolassa saatu ohjeistus ehkäisi selvästi karieksen syntyä puolen vuoden kokeessa.