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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.
271

Estudo de um modelo experimental para o desenvolvimento de enfisema pulmonar induzido por elastase e fumo em camundongos / An experimental model of elastase and cigarette smoke-induced emphysema in mice

Rubia Rodrigues 26 June 2015 (has links)
Os modelos experimentais têm sido utilizados para o estudo dos mecanismos fisiopatológicos envolvidos no desenvolvimento da Doença Pulmonar Obstrutiva Crônica (DPOC). O modelo que melhor mimetiza a doença em humanos é o que utiliza a exposição à fumaça de cigarro. No entanto, a utilização deste modelo experimental requer um longo tempo de exposição (6 meses) e a lesão do parênquima obtida é considerada leve. O desequilíbrio protease/anti-protease é considerado um importante mecanismo fisiopatológico envolvido no desenvolvimento da DPOC. Desta forma, neste estudo propomos o desenvolvimento de um modelo experimental no qual associamos a instilação de elastase previamente ao início da exposição ao fumo na tentativa de obter um maior grau de lesão tecidual em um menor espaço de tempo. Para tanto, camundongos C57Bl/6 foram divididos em quatro grupos: Controle, Elastase, Fumo, Fumo/Elastase 1 dose e Fumo/Elastase 2 doses e analisados após dois meses de exposição. Os animais do grupo Fumo/Elastase 1 dose e 2 doses foram submetidos à instilação intranasal de elastase pancreática de porco (0,33UI) e expostos a fumaça de cigarro por dois meses. O grupo controle recebeu o mesmo tratamento com solução fisiológica (NaCl 0.9%). A exposição ao fumo foi feita por 30min, 2 vezes/dia, 5 dias da semana. Após dois meses, os animais foram sacrificados e observamos aumento de LM no grupo Fumo/Elastase 1 dose e 2 doses comparado aos grupos Controle e Fumo; aumento de células positivas para MAC-2 no parênquima (Fumo/Elastase 2 doses) e vias aéreas (Fumo/Elastase 1 dose e 2 doses), MMP-12 no parênquima pulmonar (Fumo/Elastase 2 doses), GP91 no parênquima (Fumo/Elastase 1 dose e 2 doses) e vias aéreas (Fumo e Fumo/Elastase 1 dose) e aumento de proporção de fibras elásticas no parênquima pulmonar do grupo Fumo/Elastase 1 dose e do grupo Fumo, caracterizando presença de enfisema pulmonar. A instilação de elastase pancreática de porco juntamente com a exposição à fumaça de cigarro aumentou a susceptibilidade ao desenvolvimento do enfisema / Experimental models have been used to study the pathophysiological mechanisms involved in the development of COPD. Cigarette Smoke exposure (CS) is considered the best model to mimetize the disease in humans. However, the CS requires a long exposure time (6 months) and the parenchymal destruction obtained is considered mild. The protease / anti - protease imbalance is considered an important pathophysiological mechanism involved in the development of COPD. Thus, in this study we propose the development of an experimental model in which we associate instillation of elastase before the start of exposure to smoke, trying to increase the parenchymal destruction degree in a shorter time. For that, C57BL / 6 mice were divided into four groups: Control, Elastase, Smoke and Smoke/Elastase 1 dose and Smoke/Elastase 2 doses and analyzed in two months after the CS exposition. The Smoke/Elastase 1 dose and 2 doses animals group received an intranasal instillation of porcine pancreatic elastase (0.33 IU) and exposed to cigarette smoke for two months. The control group received the same treatment with saline (NaCl 0.9 %). Animals were exposed to CS for 30min, 2 times / day, 5 days a week. After two months, we observed increased mean linear intercept (LM) and positive cells for MAC-2, MMP-12 and GP91 in the airways and lung parenchyma and increase of elastic fibers in the lung parenchyma characterizing the presence of pulmonary emphysema. The instillation of porcine pancreatic elastase along the exposure to cigarette smoke increased susceptibility to the development of emphysema
272

Estudo de fatores prognósticos clínicos e biomoleculares de pacientes portadores de câncer de vulva submetidos a tratamento cirúrgico / Study of biomolecular and clinical prognostic factors in patients with vulvar cancer undergoing surgical treatment

Paulo Henrique Zanvettor 31 January 2014 (has links)
INTRODUÇÃO: O câncer de vulva representa entre 3 a 5% dos cânceres do trato genital feminino e aproximadamente 0,6% dos cânceres da mulher. Existem poucos estudos na literatura sobre fatores prognósticos incluindo avaliação molecular, relacionados a esta doença. Este estudo foi realizado para avaliar fatores prognósticos clínicos, epidemiológicos, patológicos e moleculares de pacientes portadores de câncer de vulva submetidos a tratamento cirúrgico. Avaliamos também uma classificação de prognóstico com base na pontuação do risco relativo dos fatores encontrados. MÉTODOS: Foram selecionadas as pacientes portadoras de carcinoma escamocelular de vulva, submetidas a tratamento cirúrgico no Departamento de Cirurgia Pélvica e Serviço de Ginecologia do Hospital Aristides Maltez entre o período de Junho de 1993 e Junho de 2011. Avaliamos as características clínicas, epidemiológicas, de anatomia patológica e molecular, em relação ao prognóstico das pacientes. A avaliação molecular estudou a expressão da proteína p53 e metaloproteinase 2 de matriz por exame de imunohistoquímica pela técnica de arranjo em matriz de amostras teciduais (TMA). Com base no banco de dados realizado através de consulta aos prontuários e com os resultados de anatomia patológica e testes imunohistoquímicos realizamos análise estatística em relação à sobrevida global das pacientes.RESULTADOS: Setenta e cinco pacientes foram elegíveis para o estudo. A análise univariada mostra como fatores relacionados à sobrevida foram a presença de linfonodo suspeito de metástase ao exame clínico (p=0,004), o tamanho maior de 4 centímetros (p=0,001), a presença de linfonodo com metástase (p=0,026), o estadiamento por grupos (p=0,001), a localização mediana (p=0,011), a profundidade de infiltração maior de 2 milímetros (p=0,012), a expressão da MMP 2 em mais de 50% das células (p=0,009). Na análise multivariada os fatores relacionados à sobrevida foram o tamanho maior de 4 centímetros (p=0,014), a profundidade de invasão maior de 2 milímetros (p=0,023) e a expressão de MMP2 em mais de 50% das células (p=0,046). De acordo ao risco relativo dos fatores identificados como relacionados ao prognóstico pela análise multivariada, foi elaborada a contagem de pontos para uma classificação prognóstica. Essa pontuação classifica em três categorias conforme a presença ou ausência dos fatores identificados na análise multivariada e pode corresponder a três expectativas de sobrevida. CONCLUSÕES: Os fatores tamanho maior de 4 centímetros, profundidade de invasão maior de 2 milímetros e expressão em mais de 50% das células tumorais de metaloproteinase 2 parecem estar relacionados a menor taxa de sobrevida global de pacientes portadores de câncer de vulva submetidas a tratamento cirúrgico. Pode ser realizada uma classificação para o prognóstico de acordo com uma contagem de pontos atribuídos ao risco relativo destes fatores / INTRODUCTION: Vulvar cancer accounts for 3-5% of all cancers of the female genital tract and approximately 0.6% of women\'s cancers. There are few studies on prognostic factors including molecular evaluation related to this disease. This study was conducted to evaluate clinical, epidemiological, pathological and molecular prognostic factors of patients with vulvar cancer, undergoing surgical treatment. A classification based on prognostic risk score related to the factors found was also evaluated. METHODS: Patients were selected with squamous cell carcinoma of the vulva who underwent surgical treatment at the Department of Pelvic Surgery and Department of Gynecology, Hospital Aristides Maltez between the period of June 1993 and June 2011. Clinical, epidemiological, and molecular and pathological anatomy characteristics were evaluated in relation to the prognosis of patients. Molecular assessment studied the expression of p53 protein and metalloproteinase 2 by immunohistochemical examination through the technical arrangement on matrix tissue samples (TMA). Based on the database performed on medical records held and the results of pathological anatomy and immunohistochemical tests, the statistical analysis was performed with respect to overall survival of patients. RESULTS: Seventy-five patients were eligible for the study. Univariate analysis shows how factors related to survival were the presence of lymph node metastasis suspected on clinical examination (p = 0.004), the larger size of 4 cm (p = 0.001), presence of lymph node metastasis (p = 0.026), staging groups (p = 0.001), the location median (p = 0.011), the depth of infiltration larger than 2 millimeters (p = 0.012), the expression of MMP 2 in more than 50% of the cells (p = 0.009). In multivariate analysis, factors related to survival were larger size than 4 cm (p = 0.014), depth of invasion greater than 2 mm (p = 0.023) and MMP2 expression in more than 50% of cells (p = 0.046). According to the relative risk of factors identified as related to prognosis by multivariate analysis, a score was developed for a prognostic classification. This score classifies into three categories, according to the presence or absence of the factors identified in the multivariate analysis and may correspond to three survival expectations. CONCLUSIONS: Prognostic factors as the size larger than 4 centimeters, depth of invasion greater than 2 mm and expression in more than 50% of tumor cells of metalloproteinase 2 may be related to lower overall survival rate of patients with cancer of the vulva undergoing surgery. Classification may be performed for the prognostic according to a count point attributed to the relative risk of these factors
273

Chairside-Nachweis aktivierter Matrixmetalloproteinase-8 (aMMP-8) sowie Detektion potenziell parodontalpathogener Bakterien zur parodontalen Risikoeinschätzung in der Blutspende / Eine klinische Querschnittstudie in der Transfusionsmedizin Göttingen / Point-of-care diagnostic of activated matrix metalloproteinase-8 (aMMP-8) and detection of potentially periodontal pathogenic bacteria to estimate the risk of periodontal diseases in blood donation / A clinical cross-sectional study in the Department of Transfusion Medicine Göttingen

Hübscher, Anna Elisabeth 18 December 2017 (has links)
No description available.
274

Studies On Intracrine Regulators Of Ovarian Function : Examination Of Progesterone Action On Structure And Function Of Corpus Luteum In The Monkey

Suresh, P S 11 1900 (has links) (PDF)
The control of reproductive cycles in higher primates is largely dependent on negative and positive feedback mechanisms by both steroidal and non-steroidal substances of the ovaries which regulate the function of hypothalamo-pituitary system. To gain insights into the role of INH A, the non steroidal ovarian hormone in the feedback control of pituitary FSH secretion, studies were conducted to examine the interrelationships of hormones throughout the menstrual cycle of the bonnet macaque. The findings of chapter II provide a detailed description of endocrine hormone profile during the menstrual cycle of the bonnet macaques with special attention to the feedback role of INH A on pituitary FSH secretion. To characterize the endocrine profile of different hormones, both ovarian (E2, P4, INH A) and pituitary (FSH, LH) hormones were measured daily for more than 40 days. To further examine the site of secretion of INH A and its relationship with pituitary FSH dynamics, surgical lutectomy and pharmacological induction of luteolysis employing the third generation GnRH R antagonist, Cetrorelix (CET) studies were carried out in the subsequent experiments. The results obtained from these studies suggest that INH A and P4 secreted from the CL during luteal phase regulate pituitary FSH secretion. The selective rise in FSH observed during the late menstrual cycle and during menstruation (referred to as luteo-follicular transition), as has been reported previously in higher primates, considered necessary for initiation of follicular growth and recruitment of follicles for ensuing menstrual cycle was characterized in the monkey. Surgical lutectomy and induction of luteolysis by CET experiments suggested that increased GnRH secretion is essential for this selective rise in FSH following withdrawal of inhibition by P4 and INH A. In clinical cases of reproductive ageing, the shortened follicular phase in human females has been identified to be the result of occurrence of early onset of FSH rise during the luteal-follicular transition period. The cause(s) of declining fertility with age in women who still have regular menstrual cycles are not clear, but issues of relationship between dysregulation of selective FSH rise in the late luteal phase and associated infertility could be examined using bonnet monkey as a model system. INH A is secreted in significant quantities by CL in higher primates and the feto placental unit suggesting its importance during fertility and pregnancy. Apart from the negative feedback regulation of pituitary FSH secretion, the complete repertoire of actions of this hormone during pregnancy is yet to be fully understood. The data presented in this thesis is the first comprehensive report showing the endocrine hormone profile of gonadotropins and ovarian hormones including INH A throughout the menstrual cycle of the bonnet macaque. The characterization of INH A profile in bonnet monkey will be of significant value for studies examining the role of INH A in higher primates. Dimeric inhibin has been suggested to be important for regulation of fertility and reproductive functions. Also, inhibin-α (one of the subunits of the dimeric protein) knock out mice model has provided convincing evidence that it acts as a tumour suppressor. A great deal of new information has been generated in recent years regarding the potential clinical usefulness of monitoring inhibin levels in blood and biological fluids in gynaecological diseases, pathological pregnancies and other disorders. Emerging clinical roles of inhibin have made INH A an important candidate molecule to study its molecular regulation. The results presented in chapter II suggested that LH regulates luteal INH A secretion (induction of luteolysis by CET administration experiment). As a first step towards understanding molecular regulation of inhibin-α expression in the macaque CL, in silico promoter analysis of macaque inhibin-α was performed and it revealed several transcriptional factor binding sites that were conserved across species. In rats FSH up regulates while preovulatory LH surge suppresses inhibin-α mRNA expression in the ovary and this suppression has been suggested to be necessary for occurrence of secondary FSH surge during metestrus. To address differential regulation of inhibin-α by LH and FSH in rat ovary during the periovulatory period, studies employing immature rats were carried out and the results are presented in chapter III. The results suggest that immature rat ovaries respond to exogenous gonadotropins in terms of LH signaling (cAMP production), luteinization (P4 production) and as well induction of ICER expression required for repression of inhibin-α subunit expression. PDE4 inhibitor (rolipram) treatment enhanced the ovarian cAMP concentrations suggesting that PDE4 play a major role in controlling intraovarian cAMP concentrations in rat ovaries. However increased cAMP concentrations did not appear to up regulate the ICER expression at the time point examined in this study. In higher primates time course of second FSH surge and continued synthesis and secretion of INH A in the CL are different from non primate species. In the monkey, the second FSH rise occurs during the late luteal phase and experiments have been carried out to examine the regulation of inhibin-α subunit expression by ICER. Expressions of ICER (mRNA/protein) and INH A were examined during different stages of CL and the results indicated no clear inverse relationship between the ICER and inhibin-α mRNAs. With no conclusive role for the ICER in regulating luteal inhibin-α observed in the study, the role of transcriptional activators in the regulation of inhibin-α like GATA4, SF-1, β-catenin were further examined. Since luteal INH A secretion was dependent on pituitary LH as determined earlier in chapter II, expressions of transcriptional activators were examined in CL of different stages and also during induced luteolysis and the results are described in chapter IV. In conclusion, our results indicate cross talk between WNT, cAMP and P38 MAP kinase signaling pathways in the regulation of luteal INH A secretion. The pituitary gonadotropin, LH, is the primary luteotropin in primate species acting to maintain the structure and function of the CL during the menstrual cycle. However whether the actions of LH are direct or mediated by local factors such as P4 remain unknown. Moreover, P4 secretion which is dominant during luteal phase has any role in regulating CL structure and function is not clearly defined. To address these and issues concerning P4 actions, initially, experiments were performed in the rat model to study the importance of P4 in the regulation of ovarian functions. An antiprogestin, RU486, was employed as a tool to uncover the PR regulated pathways during ovulation in rats and the findings are presented in the chapter V. The results indicated that blockade of PR action by RU486 during gonadotropin-induced superovulation resulted in inhibition of follicular rupture and ovulation in immature rats. Further to understand the downstream effectors of PR action, and to identify the candidate target genes of PR activation, semi-quantitative RT-PCR and western blot analyses were performed. The results obtained indicated that betacellulin, a member of EGF family and MMP-9 a proteolytic enzyme, were markedly repressed in response to RU486 treatment in rat ovaries. Also, the down stream pathway of EGF signaling leading to activation of ERK was markedly repressed in RU486 treated ovaries. It was next examined what role the P4/PR system has in the regulation of CL structure and function. Surprisingly, PR expression is absent in CL of rats, while it is present in higher primates. Experiments were carried out to examine intracrine actions of P4 in the regulation of CL structure and function in monkeys. The recently reported model system of induced luteolysis yet capable of responsive to trophic support from the laboratory provided an ideal opportunity to examine direct effects of P4 on structure and function of CL in the monkey. A series of pilot experiments were carried out in monkeys experiencing summer amenorrhea, to determine dose and mode of administration of exogeneous P4 to simulate mid luteal phase circulating P4 concentrations in monkeys subjected to induced luteolysis. Based on the results of pilot experiments, implantation of Alzet pumps containing 97.5mg of P4 was selected for maintaining mid luteal phase P4 concentrations. The microarray data of induced luteolysis previously deposited by the laboratory in NGBI’s gene expression omnibus were mined for identification and validation of differentially expressed genes of PR and its target genes following LH depletion and LH replacement experiments. Expressions of PR, PR cofactors and expressions of PR downstream target genes through out the luteal phase and in CL from day1 of menses were also examined. Analysis of expressions of genes revealed that of the 45 genes identified to be regulated by LH treatment, 4 genes were found to be responsive to P4, and 14 were identified to be responsive to both P4 and LH. Morphology of CL tissue sections revealed that P4 treatment appeared to have reversed the induced-luteolysis changes. In another experiment, implantation of P4 during late luteal phase (i.e., the period of declining P4 concentrations) for 24h caused changes in expressions of genes associated with tissue remodeling and morphology of luteal cells. Taken together, the results suggest that induced luteolysis plus P4 replacement model is suitable for assessing the effects of P4 on CL function. The results also suggest that CL could serve as target tissue for examining the genomic and non genomic actions of P4. In summary, studies carried out in the present thesis provides a comprehensive endocrine hormone profile throughout the menstrual cycle of the bonnet monkey with special emphasis on time course of INH A and FSH secretion which is very useful for future investigations. Studies have been carried out in rats and monkeys with different experimental model systems to address molecular mechanisms underlying inhibin-α regulation in the ovary in general and CL in particular. Experimental findings in monkeys could help elucidate the underlying molecular nature of CL functionality and extrapolate to understand luteal insufficiency and infertility producing conditions in humans. Also different model systems have been validated to examine the actions of P4/PR system in rats and monkeys and more importantly to address the direct effects of P4 upon monkey CL structure and function were established. Future investigations based on findings of these studies should help clarify relative roles for LH and P4 during maintenance of CL function and luteolysis.
275

Biomarkery zánětlivého postižení subchondrální kosti při axiální spondyloartritidě. / Biomarkers of subchondral bone damage caused by inflammation in axial spondyloarthritis.

Bubová, Kristýna January 2020 (has links)
Background: Axial spondyloarthritis (axSpA) is a chronic inflammatory rheumatic disease affecting primarily the spine and its adjacent structures. The disease is characterized not only by destructive joint changes but also by excessive osteoproduction, which can lead to gradual ankylosis of the spine and thus significantly reduce the mobility and quality of life. The pathogenesis of the disease is not yet fully understood, but a strong genetic background is suggested, along with dysregulation of tissue metabolism resulting from an imbalance of pro- and anti-inflammatory immune mechanisms. We are still lacking biomarker with sufficient sensitivity and specificity which could help to identify early diagnosis, to monitor subchondral damage, and to differentiate rapidly progressing patients. The aim of this work was to determine the levels of potential biomarkers of connective tissue metabolism, fat metabolism and new promising biomarkers for both disease subtypes, their relationship to disease activity and progressive structural changes. Results: We have shown increased serum/plasma levels of connective tissue metabolism biomarkers (especially matrix metalloproteinase mediated metabolites), which were able to differentiate patients with early and late forms of axSpA from healthy individuals (HC), were...
276

Impact of autocrine factors on physiology and productivity in Trichoplusia ni serum-free cultures

Eriksson, Ulrika January 2005 (has links)
The aim of this study was to increase the understanding of the mechanisms regulating cell proliferation and recombinant protein production in serum-free cultures of Trichoplusia ni (T. ni) insect cells. Conditioned medium (CM) was shown to contain both stimulatory and inhibitory factors (CM factors) influencing cell growth. Metalloproteinase (MP) activity was the major factor responsible for the growth stimulating effect of CM as shown by using the specific MP inhibitor DL-thiorphan. MPs may exist in several different molecular mass forms due to autoproteolysis. Although the main band of the MP was determined to be around 48 kDa, precursor forms above 48 kDa as well as autocatalytic degradation products below the main band could be observed. It is not clear whether all forms of the MP or just the main band is involved in the growth regulation. Further, a proteinase inhibitor could be identified in the inhibitory fraction. Thus, we speculate that the proteinase inhibitor may be part of an autocrine system regulating cell proliferation. Analysis of the cell cycle phase distribution revealed a high proportion of cells in the G1 (80-90 %) and a low proportion of cells in the S and G2/M phases (10-20 %) during the whole culture, indicating that S and G2/M are short relative to G1. After inoculation, a drastic decrease in the S phase population together with a simultaneous increase of cells in G1 and G2/M could be observed as a lagphase on the growth curve and this may be interpreted as a temporary replication stop. When the cells were released from the initial arrest, the S phase population gradually increased again. This was initiated earlier in CM-supplemented cultures, and agrees with the earlier increase in cell concentration. Thus, these data suggests a correlation between CM factors and the cell cycle dynamics. In cultures supplied with CM, a clear positive effect on specific productivity was observed, with a 30 % increase in per cell productivity. The specific productivity was also maintained at a high level much longer time than in fresh-medium cultures. The positive effect observed after 20 h coincided with the time a stimulatory effect on cell growth first was seen. Thus, the productivity may be determined by the proliferation potential of the culture. A consequence of this would be that the secreted MP indirectly affects productivity. Finally, the yeast extract from Express Five SFM contains factors up to 35 kDa which are essential for T. ni cell growth. The optimal concentration was determined to be 2.5-fold that in normal medium, while higher concentrations were inhibitory. However although vital, they were not solely responsible for the growth-enhancing effect, as some other, more general, component present in yeast extract was needed for proliferation as well. / <p>QC 20101129</p>
277

The Responses of Human Neutrophils to Tobacco Smoke Components

Al-Shibani, Nouf Khider January 2012 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Tobacco smoking is considered a major modifiable risk factor for periodontal disease. Tobacco contains about 6700 compounds and almost 4000 compounds of these have been identified in tobacco smoke. Nicotine is the addictive ingredient in tobacco and has been shown to affect multiple cellular processes. Cigarette smoke condensate (CSC) is the particulate matter of smoke. It is believed to be a powerful inducer of inflammatory responses. Neutrophils are the first line of host defense and are critical cells in the maintenance of periodontal health through their role in the control of bacteria, but they can also contribute to the progression of periodontal disease by the production and release of reactive oxygen species (ROS). Virulence factors from periodontal pathogens, such as Porphyromonas gingivalis (P. gingivalis), stimulate the respiratory burst of neutrophils. In this dissertation, three studies aimed at understanding the oxidative activity of neutrophils when stimulated with either nicotine, cigarette smoke condensate (CSC) or four other components of tobacco smoke (2-naphthylamine, hydroquinone, acrolein, and acetaldehyde) with or without P. gingivalis supernatant. The release of matrix metalloproteinase-9 (MMP-9) was also examined. ROS production increased significantly when the neutrophils were stimulated with nicotine. P. gingivalis induced the maximum ROS production when compared to all the other components examined. The combination of nicotine and P. gingivalis did not have an additive effect on ROS production. Nicotine significantly increased the MMP-9 release from the neutrophils. On the contrary, CSC inhibited ROS production at all the concentrations examined. The combination of CSC and P. gingivalis resulted in the inhibition of ROS production. MMP-9 release was also increased from the CSC-treated neutrophils. The four other tobacco smoke components examined affected ROS production and MMP-9 release differently. These projects demonstrated that CSC inhibited the ROS production from neutrophils, which can be attributed to several components in tobacco smoke that may include acrolein and hydroquinone. More research is needed to determine the mechanisms of inhibition and if other tobacco components are involved in ROS inhibition
278

<b>Agent-Based Modeling of </b><b>Cell Culture Granuloma Models: </b><b>The Role of Structure, Dimension, Collagen, and Matrix Metalloproteinases</b>

Alexa A Petrucciani (18422784) 22 April 2024 (has links)
<p dir="ltr">Tuberculosis (TB) remains a global public health crisis, causing over 10 million new infections and 1.3 million deaths in 2022 alone. TB is caused by <i>Mycobacterium tuberculosis </i>(<i>Mtb</i>), which initiates heterogeneous pathology in the lungs, including granulomas and cavities. Granulomas are organized structures of immune cells, traditionally thought to contain bacteria. Cavities are pathological spaces caused by the destruction of extracellular matrix (ECM), which can worsen disease outcomes and cause long-lasting pulmonary impairment.<i> In vitro </i>methods are commonly used to study host-pathogen interactions in <i>Mtb</i> infection, and recent developments have led to models that represent the TB granuloma environment more closely than traditional cell culture. These advances include the development of 3D models and the inclusion of physiological ECM components like collagen. Increasing complexity has been accomplished in a piece-wise manner – minimally necessary components are included to minimize cost while maintaining throughput and tractability. This creates a need for tools to analyze these systems and, more importantly, integrate the independent data created. We developed an agent-based model to characterize multiple <i>in vitro</i> models of TB and apply it to 1) separate the contributions of dimension and structure to bacterial control in granuloma-like spheroids and 2) explore how the interactions of collagen and matrix metalloproteinases (MMP) contribute to clinically relevant outputs such as bacterial load and ECM destruction. The model provides insights into the role of granuloma structure and the conflicting results of MMP inhibition, generating new hypotheses to be tested in tandem with <i>in vitro</i> models.</p>
279

Nové biomarkery u pacientů s onemocněním ledvin / Novel biomarkers in patients with renal disease

Zakiyanov, Oskar January 2014 (has links)
Chronic kidney disease (CKD) and acute kidney injury (AKI) are major public health problems. It is important to be able to identify those at high risk of adverse outcome, CKD progression and associated cardiovascular disease. The aim of the thesis was to study novel promising biomarkers, their relationship to kidney function, chronic inflammation and/or cardiovascular risk - placental growth factor (PlGF), pregnancy associated plasma protein A (PAPP-A), matrix metalloproteinase 2 (MMP-2), matrix metalloproteinase 9 (MMP-9), soluble receptor for advanced glycation end products (sRAGE), calcium binding protein S100A12 or extracellular newly identified RAGE binding protein (EN-RAGE), and high mobility group box protein-1 (HMGB-1) in patients with renal diseases including CKD, haemodialysis (HD), AKI patients, and healthy controls for comparison. First study revealed that PlGF is elevated in patients with decreased renal function. Second study demonstrated the association of MMP-2 and PAPP-A with proteinuria in patients with CKD. Moreover, serum MMP-2, MMP-9 and PAPP-A levels significantly differed in patients with various nephropathies. EN-RAGE levels are not elevated in patients with CKD, but are related to inflammatory status. PAPP-A, EN-RAGE and HMGB-1 levels are significantly elevated, but sRAGE and PlGF...
280

Nové biomarkery u pacientů s onemocněním ledvin / Novel biomarkers in patients with renal disease

Zakiyanov, Oskar January 2014 (has links)
Chronic kidney disease (CKD) and acute kidney injury (AKI) are major public health problems. It is important to be able to identify those at high risk of adverse outcome, CKD progression and associated cardiovascular disease. The aim of the thesis was to study novel promising biomarkers, their relationship to kidney function, chronic inflammation and/or cardiovascular risk - placental growth factor (PlGF), pregnancy associated plasma protein A (PAPP-A), matrix metalloproteinase 2 (MMP-2), matrix metalloproteinase 9 (MMP-9), soluble receptor for advanced glycation end products (sRAGE), calcium binding protein S100A12 or extracellular newly identified RAGE binding protein (EN-RAGE), and high mobility group box protein-1 (HMGB-1) in patients with renal diseases including CKD, haemodialysis (HD), AKI patients, and healthy controls for comparison. First study revealed that PlGF is elevated in patients with decreased renal function. Second study demonstrated the association of MMP-2 and PAPP-A with proteinuria in patients with CKD. Moreover, serum MMP-2, MMP-9 and PAPP-A levels significantly differed in patients with various nephropathies. EN-RAGE levels are not elevated in patients with CKD, but are related to inflammatory status. PAPP-A, EN-RAGE and HMGB-1 levels are significantly elevated, but sRAGE and PlGF...

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