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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Designs and Applications of Surface Acoustic Wave Sensors for Biological and Chemical Sensing and Sample Handling

Cular, Stefan 15 February 2008 (has links)
Acoustic wave sensors have proven useful in many fields as primarily mass sensitive devices capable of responding to small environmental perturbations. The focus of this dissertation is the development of a new type of surface acoustic wave device with application to material property measurement, and biological and chemical sensing. This device is a combination of three independent acoustic wave devices with these waves propagated across the same area, while retaining independence of actuation and sensor function. The development of a complete sensor system, and its use and operation are presented for several example cases of chemical and biomarker sensing, and sample manipulation. These include experimental and theoretical studies for organic vapor sensing, biological moiety sensing, acoustic streaming to remove loosely bound material, and optimization of designs for these applications.
2

Real Time Surface Plasmon Resonance Biosensors, a Powerful Technology to Assess Polyclonal Antibody Avidity

Canelle, Quentin 11 September 2015 (has links)
The present research focused on the development of a new methodology to assess the strength of the interaction between vaccine antigens and elicited polyclonal antibodies through SPR biosensors. Quantifying the binding strength of polyclonal antibodies is of first importance to evaluate the quality of the vaccine as well as to increase the scientific knowledge of immune protection mechanisms. To now the development of such tool has been complicated by the non-specific binding caused by high protein abundance in the blood and serum samples but also by the way of interpreting the data resulting from multi-interaction events measured at the same time. At first, we unsuccessfully tried to segregate the individual affinity contribution of each antibody population by measuring the signal as the sum of singular interactions. Differentiation of the singular contribution would have needed the fulfillment of the “additivity” hypothesis, meaning that each antibody bind identically alone or in mixture with other antibody. This hypothesis was not met and mathematical assessment by the sum of singular contribution led to fitting results that did not reflect the biological reality. It was therefore decided to switch the analysis method and to measure the end association binding level reached by the different samples injected at the same specific antibody content. The dissociation behavior was interpreted by the percentage of binding after long and fixed dissociation time. In a first application, we compared the antibodies elicited by two different commercially available vaccines and we showed that the binding interaction was not concentration dependent as, highly different levels were reached when injecting identical antibody concentration. No statistical significant difference was observed between both vaccines. Research firstly focused on the decrease of the non-specific binding and we found that ionic strength was a key parameter, increasing the buffer salt concentration reduced the non-specific binding without diminishing the binding strength. The sample composition was also a key parameter and purifying the IgG allowed to decrease dramatically the undesired binding events. A second application aimed at showing the equivalence between two different antigen constructions for two antibodies population. Even if identical antigen level immobilization is a challenge, the methodology is completely suitable to perform a 2-dimensional comparison (ligand and analyte). A last application was dedicated to the comparison between D and Q-pan Flu vaccines, and results showed that there was no statistical evidence of significant differences between both vaccines. End association level correlated well with haemagglutination inhibition assay at least when serum samples were not diluted at the same antibody content. This last application also showed that throughput may be extended to more than 50 samples per 80 hours / Doctorat en Sciences agronomiques et ingénierie biologique / info:eu-repo/semantics/nonPublished
3

Ospecifik ländryggssmärta : Fysioterapeutiska åtgärder inom primärvården i Sverige / Nonspecific low back pain : Physiotherapeutic measures in primary care in Sweden

Sandqvist, Frej, Yan, Kevin January 2022 (has links)
Ospecifik ländryggssmärta är den vanligaste typen av ländryggssmärta och saknar identifierbar patoanatomisk orsak, därför har det blivit en utmaning att utveckla effektiva behandlingar. Det saknas nationella riktlinjer i Sverige för fysioterapeutisk behandling av ospecifik ländryggssmärta. Det är oklart vilka typer av åtgärder som idag används av svenska fysioterapeuter.  Syftet med studien var att kartlägga vilka fysioterapeutiska åtgärder för ospecifik ländryggssmärta som används av fysioterapeuter i Sverige samt undersöka om det föreligger eventuella skillnader i val av åtgärd mellan offentligt och privat anställda fysioterapeuter och mellan kvinnliga och manliga fysioterapeuter.  Studien var en kvantitativ tvärsnittsstudie av deskriptiv och komparativ design. Urvalet var ett bekvämlighetsurval bestående av yrkesverksamma fysioterapeuter i Sverige. Data samlades in via en enkät som besvarades av 105 fysioterapeuter.  De mest frekvent använda åtgärderna var information och råd kring fysisk aktivitet, sedan följde information om ergonomi, information om smärtmekanismer, muskelstärkande träning samt träning av rörlighet. Privat anställda fysioterapeuter använde laserterapi (p=0.020), massage (p=0.006), samt yoga (p=0.013) oftare i genomsnitt jämfört med offentligt anställda. McKenzie träningsprogram (p=0.010) var mer frekvent använt av offentligt anställda i genomsnitt. Kvinnliga fysioterapeuter använde aerob träning (p=0.012), akupunktur (p=<0.001), information om ergonomi (p=0.023), träning av balans (p=0.013), träning av bålstabilitet med motorisk kontroll (p=0.012), träning av rörlighet (p=0.016) samt TENS (p=<0.001) oftare än manliga.      Studien visade att det i övrigt fanns mycket likhet mellan grupper men att typen av anställning samt kön kan påverka till en viss utsträckning val av åtgärder. / Nonspecific low back pain is the most common type of low back pain and lacks an identifiable pathoanatomical cause, which makes it difficult to develop effective treatments. There are no national guidelines in Sweden for this condition and it is unclear what methods are currently used by Swedish physiotherapists. The purpose of the study was to map physiotherapeutic measures for nonspecific low back pain used by physiotherapists in Sweden and to investigate whether there are differences between public and private physiotherapists and between female and male physiotherapists. The study was a quantitative cross-sectional study of descriptive and comparative design. The sample was a convenience sample and the data were collected via a questionnaire that was answered by 105 physiotherapists.  The most frequently used methods were information and advice on physical activity, followed by information about ergonomy, information on pain mechanisms, muscle-strengthening training and training of mobility. Laser therapy (p=0.020), massage (p=0.006) and yoga (p=0.013) were more often used by public physiotherapists while McKenzie training programme (p=0.010) was more often used by public physiotherapists. Female physiotherapists used aerobic training (p=0.012), acupuncture (p=<0.001), information about ergonomy (p=0.023), training of balance (p=0.013), training of core stability with motorical control (p=0.012), träning of mobility (p=0.016) and TENS (p=<0.001) more often than male physiotherapists.  The study showed that there were strong similarities between groups but that the type of employment and gender can affect to a certain degree the choice of measures.
4

The Withdrawn and Sociable Behaviors of Children with Specific and Nonspecific Language Impairment

Haskin, Heather 05 August 2009 (has links) (PDF)
Recently researchers have identified a group of children with language impairment (LI) whose IQ scores are below the typical IQ cutoff of 85 for specific language impairment (SLI) but above the IQ cutoff of 70 for intellectual disability (Weismer et al., 2000). This group is referred to as having nonspecific language impairment (NLI). Eleven children with NLI, eleven same-age peers with SLI, and eleven same-age typical peers were compared on withdrawn and sociable behaviors demonstrated in the classroom setting using the Teacher Behavior Rating Scale (Hart & Robinson, 1996). Three subtypes of withdrawal (solitary-active, solitary-passive, reticent) and two subtypes of sociable behavior (impulse control/likability and prosocial) were examined. The children were compared on the severity of their ratings as well as the pattern of item responses for each behavioral subtype. Teachers rated the group with NLI significantly more poorly than the typical group on the reticence, impulse control/likability, and prosocial subtypes. Teachers rated the group with SLI significantly more poorly than the typical group on the impulse control/likability subtype. Participants were added to the typical group and the group with SLI to increase statistical power. With additional participants, the children with SLI were also rated significantly more poorly than the typical children on the reticence, likability, and prosocial subtypes. The group with NLI was consistently rated more poorly than the group with SLI except on the solitary-active subtype. However, there were no significant differences between the groups with LI, even with additional participants. The pattern of item responses was similar between the groups with NLI and SLI on all behavioral subtypes. In addition, the pattern of item responses for the groups with LI also matched the pattern of the typical group on the solitary-active withdrawal, impulse control/likability, and prosocial subtypes. These data indicate that the differences between the groups with NLI and SLI may be quantitative but not qualitative.
5

BEAD-BASED IMMUNOASSAYS WITH ELECTROCHEMICAL DETECTION

RONKAINEN-MATSUNO, NIINA JOHANNA January 2003 (has links)
No description available.
6

Enhancing Biosensor Performance with Omniphobic Lubricant-Infused Coatings

Osborne, Matthew January 2018 (has links)
Point-of-care testing brings diagnosis and treatment monitoring to the site of the patient. It heavily relies on biosensors, which leverage the interactions between a target biomarker and a bioreceptor, to deliver fast and accurate results. However, non-specific binding of molecules and microorganisms on the biointerface can interfere with biomarker-bioreceptor interactions and diminish a biosensor’s sensitivity, specificity, and stability. In turn, this can lead to false diagnoses and ineffective treatments. Omniphobic-lubricant infused (OLI) coatings exhibit slippery, self-cleaning characteristics that repel untargeted molecules and microorganisms to augment the biosensor’s performance. In this work, we investigate the proficiency of OLI coatings in two specific applications: dissolved oxygen sensing and DNA biosensing. First, in water quality monitoring, an OLI coating is applied to the selectively permeable membranes of a dissolved oxygen sensor. Over a three-week incubation period in an environment with accelerated bacterial growth, the coated membranes exhibit a 160% higher reproducibility (10% deviation in sensitivity) and lower biofilm formation (96° static contact angle) in comparison to unmodified membranes (26%, 32°). The second application is in DNA biosensing, where a novel OLI coating uses carbon dioxide plasma activation to embed oligonucleotide probes. It demonstrates an optimized balance of slippery repellency (76° static contact angle, 10° sliding angle) and biosensing functionality, 19% longer clotting times than conventional blocking conditions, and equal sensitivity to PLL-PEG when capturing target DNA in whole blood. Going forward, our research will continue to expand the use of OLI coatings in biosensing applications, particularly exploiting its antibiofouling and anticoagulative capabilities. / Thesis / Master of Applied Science (MASc) / Biosensors are an integral tool in delivering quick and accurate point-of-care diagnosis and treatment monitoring. However, their performance can be impeded by the non-specific binding of undesirable molecules and microorganisms on the sensing surface. Omniphobic lubricant-infused (OLI) coatings have been shown to suppress biofouling and blood clotting on surfaces through exceptional repellency. This thesis focuses on the implementation of OLI coatings in biosensing applications. It investigates the antibiofouling capacity of an OLI coating on a membrane for dissolved oxygen detection. Then, it discusses a novel coating with integrated DNA biosensing functionality for working directly with blood samples. The enclosed work demonstrates that the OLI coating empowers biosensors to deliver more effective point-of-care testing.
7

The Development of the Common Factor Therapist Competence Scale for Youth Psychotherapy

Brown, Ruth 05 October 2011 (has links)
In order to continue to improve the effectiveness of psychotherapy, researchers must identify key change processes. Unfortunately, there are disparate views in the field about the relative importance and potency of specific techniques versus relationship factors. Few measures have been developed to examine the relative contribution of these factors, particularly for child-focused treatment. The Common-Factor Therapist Competence Scale for Youth Psychotherapy (COMP-CF) was developed to address this deficit. For this study, 142 video-taped sessions of child CBT for anxiety were observed and rated by independent coders using the COMP-CF. The measure demonstrated good reliability and internal consistency. Significant between-therapist and between-session differences were noted that warrant further exploration. The COMP-CF also demonstrated initial validity when compared to other observer-rater measures of therapeutic processes such as alliance, CBT-specific competence, and adherence. Recommendations for further development and refinement are discussed. Used in conjunction with adherence measures, the competence measure developed here may help improve our understanding of the therapeutic process.
8

Pesquisa de anticorpos inibidores da hemaglutinação contra o vírus da influenza equina (subtipos: H7N7 e H3N8) em equídeos provenientes do Estado de São Paulo / Detection of hemagglutination inhibition antibodies against equine influenza viruses (subtypes: H7N7 and H3N8) in horses from São Paulo State

Filippsen, Patricia 22 January 2014 (has links)
Os vírus da Influenza Equina (EIV) (H3N8 e H7N7) pertencem à família Orthomyxoviridae, gênero Influenza A. Apesar de existirem poucos relatos de infecção humana pelo EIV, é conhecido o risco zoonótico e infecção interespécies. Serviços de vigilância epidemiológica da OIE e WHO informam que o subtipo H3N8 é isolado de surtos que ocorrem mundialmente, enquanto o subtipo H7N7, menos patogênico, não é isolado desde 1980, sendo então considerado um vírus extinto. Embora o EIV seja endêmico em nosso meio, há poucos trabalhos nacionais que tenham versado sobre a avaliação atual de anticorpos (Ac) anti-EIV presentes nos equídeos do Estado de São Paulo, o que motivou a realização do presente estudo. Os objetivos do presente trabalho foram: 1) avaliar a ação de diferentes tratamentos de soro descritos pela OIE e WHO para a remoção de inibidores inespecíficos da hemaglutinação em soros de 10 equinos vacinados (H3N8 A/Equi/Kentucky/1/1997), sendo eles: a) TPH: tripsina, metaperiodato de potássio seguido de adsorção de hemácias; b) KH: kaolin 20% seguido de adsorção de hemácias; e c) RDEH: RDE seguido de adsorção de hemácias; 2) avaliar a presença de Ac contra os vírus H3N8 e H7N7, em 84 equídeos não vacinados do Estado de São Paulo; 3) comparar a frequência de Ac contra H3N8 entre equídeos amostrados do estado de SP e de um painel de soros de equídeos do município de Mossoró - RN, região onde não há estudos sobre a circulação do EIV. Constatou-se que não houve diferença estatística entre os tratamentos de soro para a remoção de inibidores inespecíficos da hemaglutinação (p>0,05; confiança de 95%), todavia o tratamento RDEH apresentou resultados mais consistentes, corroborando a recomendação da OIE e da WHO de utilizar preferencialmente este tratamento. O perfil sorológico dos animais amostrados de SP sugere que circule o subtipo H3N8 e que o subtipo H7N7 circule de forma subclínica nos equídeos, o que é sustentado por outros trabalhos realizados no Brasil. Há evidências no Brasil sobre a detecção de anticorpos em equinos contra o subtipo H7N7, mesmo não havendo o isolamento deste no mundo desde 1980. No painel de soros do RN, onde a espécie Equus asinus era maioria, verificou-se a igualdade estatística entre as frequências de Equus caballus e Equus asinus positivos no teste de HI para o subtipo H3N8 (p>0,05; confiança de 95%), dado inédito em nosso meio. A frequência dos equídeos positivos no teste de HI para o subtipo H3N8 foi estatisticamente maior (p<0,05; confiança de 95%) em SP do que em RN. / The Equine influenza Virus (EIV) (H3N8 and H7N7) belong to Orthomyxoviridae family and Influenza A genus. Although there are few reports of human infection with EIV zoonotic and interspecies infection risk is known. OIE and WHO services on epidemiological surveillance report that H3N8 subtypes are isolated and characterized from worldwide outbreaks while H7N7 subtype less pathogenic has not being isolated since 1980 considered an extinct virus. Although the EIV is endemic in our country there are few national studies that had versed on the current evaluation of horses antibodies (Ab) from São Paulo State which motivated the present study. The study objectives were: 1) to evaluate the effects of different serum treatments described by OIE and WHO for the removal of nonspecific inhibitors of hemagglutination in 10 vaccinated (H3N8 - A/Equi/Kentucky/1/1997) horses sera being: a) TPH: trypsin, potassium metaperiodate followed by adsorption of erythrocytes b) KH: kaolin 20% followed by adsorption of erythrocytes and c) RDEH: RDE followed by adsorption of erythrocytes; 2) investigate the presence of antibodies against H3N8 and H7N7 viruses in 84 unvaccinated equines in São Paulo State; 3) compare the frequency of antibodies against H3N8 sampled between São Paulo State and a panel of equines sera from Mossoró - RN where there are no studies on EIV circulation. There was no statistical difference between the treatments for serum nonspecific inhibitors of hemagglutination removal (p>0.05; 95% confidence) however RDEH treatment showed results more consistent confirming OIE and WHO recommendation to use this treatment with priority. The serological profile of SP samples suggests H3N8 subtype circulates in those animals and H7N7 subtype might circulate in a subclinical form in equines, which is supported by other studies conducted in Brazil. There is evidence of antibodies detection against equine H7N7 subtype in Brazil, even without since 1980 isolation in the world. In animals from RN State which had Equus asinus representing a major fraction there was statistical equal frequencies of Equus caballus and Equus asinus positivity in HI test against H3N8 subtype (p>0.05; 95% of confidence), as unprecedented in the world. The frequency of positive equine against H3N8 subtype on HI test in SP was statistically higher (p<0.05; 95% of confidence) than in RN.
9

Pesquisa de anticorpos inibidores da hemaglutinação contra o vírus da influenza equina (subtipos: H7N7 e H3N8) em equídeos provenientes do Estado de São Paulo / Detection of hemagglutination inhibition antibodies against equine influenza viruses (subtypes: H7N7 and H3N8) in horses from São Paulo State

Patricia Filippsen 22 January 2014 (has links)
Os vírus da Influenza Equina (EIV) (H3N8 e H7N7) pertencem à família Orthomyxoviridae, gênero Influenza A. Apesar de existirem poucos relatos de infecção humana pelo EIV, é conhecido o risco zoonótico e infecção interespécies. Serviços de vigilância epidemiológica da OIE e WHO informam que o subtipo H3N8 é isolado de surtos que ocorrem mundialmente, enquanto o subtipo H7N7, menos patogênico, não é isolado desde 1980, sendo então considerado um vírus extinto. Embora o EIV seja endêmico em nosso meio, há poucos trabalhos nacionais que tenham versado sobre a avaliação atual de anticorpos (Ac) anti-EIV presentes nos equídeos do Estado de São Paulo, o que motivou a realização do presente estudo. Os objetivos do presente trabalho foram: 1) avaliar a ação de diferentes tratamentos de soro descritos pela OIE e WHO para a remoção de inibidores inespecíficos da hemaglutinação em soros de 10 equinos vacinados (H3N8 A/Equi/Kentucky/1/1997), sendo eles: a) TPH: tripsina, metaperiodato de potássio seguido de adsorção de hemácias; b) KH: kaolin 20% seguido de adsorção de hemácias; e c) RDEH: RDE seguido de adsorção de hemácias; 2) avaliar a presença de Ac contra os vírus H3N8 e H7N7, em 84 equídeos não vacinados do Estado de São Paulo; 3) comparar a frequência de Ac contra H3N8 entre equídeos amostrados do estado de SP e de um painel de soros de equídeos do município de Mossoró - RN, região onde não há estudos sobre a circulação do EIV. Constatou-se que não houve diferença estatística entre os tratamentos de soro para a remoção de inibidores inespecíficos da hemaglutinação (p>0,05; confiança de 95%), todavia o tratamento RDEH apresentou resultados mais consistentes, corroborando a recomendação da OIE e da WHO de utilizar preferencialmente este tratamento. O perfil sorológico dos animais amostrados de SP sugere que circule o subtipo H3N8 e que o subtipo H7N7 circule de forma subclínica nos equídeos, o que é sustentado por outros trabalhos realizados no Brasil. Há evidências no Brasil sobre a detecção de anticorpos em equinos contra o subtipo H7N7, mesmo não havendo o isolamento deste no mundo desde 1980. No painel de soros do RN, onde a espécie Equus asinus era maioria, verificou-se a igualdade estatística entre as frequências de Equus caballus e Equus asinus positivos no teste de HI para o subtipo H3N8 (p>0,05; confiança de 95%), dado inédito em nosso meio. A frequência dos equídeos positivos no teste de HI para o subtipo H3N8 foi estatisticamente maior (p<0,05; confiança de 95%) em SP do que em RN. / The Equine influenza Virus (EIV) (H3N8 and H7N7) belong to Orthomyxoviridae family and Influenza A genus. Although there are few reports of human infection with EIV zoonotic and interspecies infection risk is known. OIE and WHO services on epidemiological surveillance report that H3N8 subtypes are isolated and characterized from worldwide outbreaks while H7N7 subtype less pathogenic has not being isolated since 1980 considered an extinct virus. Although the EIV is endemic in our country there are few national studies that had versed on the current evaluation of horses antibodies (Ab) from São Paulo State which motivated the present study. The study objectives were: 1) to evaluate the effects of different serum treatments described by OIE and WHO for the removal of nonspecific inhibitors of hemagglutination in 10 vaccinated (H3N8 - A/Equi/Kentucky/1/1997) horses sera being: a) TPH: trypsin, potassium metaperiodate followed by adsorption of erythrocytes b) KH: kaolin 20% followed by adsorption of erythrocytes and c) RDEH: RDE followed by adsorption of erythrocytes; 2) investigate the presence of antibodies against H3N8 and H7N7 viruses in 84 unvaccinated equines in São Paulo State; 3) compare the frequency of antibodies against H3N8 sampled between São Paulo State and a panel of equines sera from Mossoró - RN where there are no studies on EIV circulation. There was no statistical difference between the treatments for serum nonspecific inhibitors of hemagglutination removal (p>0.05; 95% confidence) however RDEH treatment showed results more consistent confirming OIE and WHO recommendation to use this treatment with priority. The serological profile of SP samples suggests H3N8 subtype circulates in those animals and H7N7 subtype might circulate in a subclinical form in equines, which is supported by other studies conducted in Brazil. There is evidence of antibodies detection against equine H7N7 subtype in Brazil, even without since 1980 isolation in the world. In animals from RN State which had Equus asinus representing a major fraction there was statistical equal frequencies of Equus caballus and Equus asinus positivity in HI test against H3N8 subtype (p>0.05; 95% of confidence), as unprecedented in the world. The frequency of positive equine against H3N8 subtype on HI test in SP was statistically higher (p<0.05; 95% of confidence) than in RN.
10

Mécanismes moléculaires de la transdifférenciation des cellules musculaires lisses et calcification dans l'athérosclérose / Molecular mechanisms of vascular smooth muscle cell trans-differentiation and calcification in atherosclerosis

Roszkowska, Monika 06 April 2018 (has links)
Chez les patients atteints d'athérosclérose, les calcifications vasculaires sont une caracteristique des plaques d'athérome. Elles résultent de la trans-différenciation des cellules musculaires lisses (CMLs) en cellules de type ostéoblastique et/ou chondrocytaire, notamment en réponse à des cytokines inflammatoires. Les CMLs forment alors des cristaux par l'activité de la phosphatase alcaline non-spécifique du tissu (TNAP). A la lumière de résultats récents, nous avons émis l'hypothèse que la TNAP module la trans-différenciation des CMLs. Nos objectifs étaient donc de déterminer l'effet de la TNAP dans la trans-différenciation des CMLs, et d'étudier les mécanismes impliqués dans son induction. Nous avons observé que l'ajout de phosphatase alcaline purifiée ou la surexpression de TNAP stimule l'expression de marqueurs chondrocytaires en culture de CMLs et de cellules souches mésenchymateuses. De plus, l'inhibition de la TNAP bloque la maturation de chondrocytes primaires. Nous avons observé un rôle des cristaux formés par la TNAP, puisque l'ajout de cristaux seuls ou associés à une matrice collagénique a reproduit les effets de la TNAP. Nous suspectons que la TNAP agit en hydrolysant le PPi et en générant des cristaux. Ces cristaux ensuite induisent l'expression du facteur ostéogénique BMP-2 et l'inhibition des effets de la BMP-2 annule les effets de la TNAP. De plus, nous étions intéressés par les la localisation et la fonction de marqueurs de minéralisation comme les annexines en parallèle de la TNAP. Nous avons observé que l'activité TNAP des CMLs induit la minéralisation en grande partie quand la TNAP est associée aux vésicules matricielles et au fibres de collagène / Vascular calcification (VC) is a hallmark of atherosclerosis plaques. Calcification (formation of apatite) of advanced lesions share common features with endochondral ossification of long bones and appears to stabilize plaques. This process is associated with trans-differentiation of vascular smooth muscle cells (VSMCs) into chondrocyte-like cells. On the other hand, microcalcification of early plaques, which is poorly understood, is thought to be harmful. The two proteins necessary for physiological mineralization are tissue-nonspecific alkaline phosphatase (TNAP) and collagen. Under pathological conditions, TNAP is activated by inflammatory cytokines in VSMCs, whereas collagen is produced constantly. The activation of TNAP appears to induce calcification of these cells. Therefore, the objective of this PhD thesis was to study the role of TNAP and generated apatite crystals in the VSMC trans-differentiation and determine underlying molecular mechanisms. Based on the obtained results, we propose that activation of BMP-2, a strong inducer of ectopic calcification, and formation of apatite crystals generated by TNAP represents a likely mechanism responsible for stimulation of VSMC trans-differentiation. Moreover, we were interested in localization and function of mineralization markers such as TNAP and annexins in mineralization process mediated by trans-differentiated VSMCs and VSMC-derived matrix vesicles (MVs). We observed that, similarly as in the case of typical mineralizing cells, increased TNAP activity in VSMC-derived MVs and association with collagen were important for their ability to mineralize

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