Анализ вероятностных моделей параметрических правил принятия решений функциональной диагностики

Рассмотрена задача статистического обоснования выбора вида математической модели измерительно-логических преобразований для процедуры функциональной диагностики с учетом ограниченности априорной информации о свойствах объекта диагностики. Построена и проанализирована информационная модель процедуры диагностики, которая учитывает требования плана диагностического эксперимента и вероятностные свойства математической модели этой процедуры.The problem of statistical justification of selecting the type of the mathematical model of measuring-logical transformations for the procedure of functional diagnostics taking into account limited aprioristic information on the properties of the object of diagnostics is considered. An information model of the procedure of diagnostics taking into account the requirements of the plan of diagnostics experiment and probabilistic properties of the mathematical model of this procedure is built and analyzed

Predictive Markers of Treatment Resistance in Head and Neck Squamous Cell Carcinoma

Head and neck cancer is a common malignancy with approximately 600 000 new cases yearly. Disappointingly, the overall survival has not increased over the last decades. The concept of personalized medicine, i.e. to treat every patient with an individually planned treatment regime has gathered increased interest, but requires the establishment of novel biomarkers that can predict treatment response. The aim of this thesis is to propose novel predictive single markers or combinations of markers of response to radiation, cisplatin and cetuximab. The general methodology is to evaluate common differences of cell lines resistant to radiation, cisplatin or cetuximab compared to sensitive counterparts. In paper I, we analysed the expression of 14 proteins involved in growth control and/or apoptosis by western blot and related them to intrinsic radiosensitivity (IR) in nine cell lines. No factor had a significant correlation to IR on its own. A combination of EGFR, survivin, Bak, Smad4, and Hsp70 had the best correlation to IR (R=0.886, p=0.001). Additionally, we analysed the presence of p53 mutations in the cell lines. All cell lines had at least one missense, splice site or loss of transcript mutation. To be able to combine protein expression and presence of p53 mutations we created a system designated the number of negative points (NNP). With this system we could extract that expression of EGFR, survivin, and p53 missense or splice site mutations had the best correlation to IR (R=0.990, p<0.001). In paper II we conducted a gene expression microarray analysis of three cell lines, from which common deregulations in two cisplatin resistant cell lines was compared to a cisplatin sensitive cell line. From a bioinformatic approach of gene ontology and molecular network analysis, we defined a transcriptional profile of 20 genes. Finally, key findings were analysed in a larger panel of cell lines, where high MMP-7 expression correlated with higher cisplatin resistance. Paper III compared 4 cell lines with high IR to a radiosensitive equivalent. Using a similar bioinformatic approach as paper II, we established a transcriptional profile of 14 genes. Analysis in a larger panel of cell lines revealed that FN1 expression predicts higher IR. Paper IV establishes the cetuximab sensitivity of 35 cell lines of which 12 were resistant and five were sensitive to cetuximab. After whole genome gene copy number analysis of five cetuximab resistant and five cetuximab sensitive cell lines, and verification of key findings in a larger cell line panel, the results show that the amplification of the YAP1 gene is coupled to cetuximab resistance. In summary, this thesis proposes a number of novel markers of resistance to radiation, cisplatin, and cetuximab which could influence treatment choice in the future, following verifications in primary tumor material

On Predictive Factors of Treatment Response in Head and Neck Squamous Cell Carcinoma

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer and yearly include 500 000 new cases worldwide. The outcomes for these patients have not been significantly improved over the last decades and the five year survival is still around 50 %. Establishing predictive markers of treatment response will have great impact on the clinical management of this disease. The aim of this thesis was to elucidate markers of intrinsic response to radiotherapy and cisplatin. Combining expression patterns of 14 proteins and identifying mutations in the p53 gene, we were able to incorporate both protein and genetic changes to create a predictive model termed Number of Negative Points (NNP). We used the NNP model to statistically calculate the combination of factors that had the best correlation to intrinsic radiosensitivity (IR). We established that a panel of three markers, epidermal growth factor receptor (EGFR), survivin and splice site/missence mutations of p53, had the best correlation to IR (R=0.990, p<0.0001). We also conducted gene expression analysis to investigate what genes and gene ontologies that are different between cell lines with varying IR. Furthermore, we wanted to identify key regulator genes with central positions of molecular networks, which were generated from the transcripts included in the deregulated gene ontologies. A transcriptional profile of 28 key regulator genes was generated. Immunoblot analysis supported deregulation at the protein level of three markers implicated from the transcriptional profile. We propose that these proteins, notch1, thrombospondin 1, and pai‐1 are predictive markers of IR. Finally, on a subset of cell lines with sensitivity or resistance to cisplatin, we performed gene expression analysis. Markers of intrinsic cisplatin sensitivity (ICS) such as gene ontologies and key regulators of molecular networks were proposed and five genes, APOE, CTNNB1, MMP7, MMP13, and THBS1 were selected for further analysis. Quantitative polymerase chain reaction (qPCR) analysis of these genes in 25 cell lines established that MMP7 (p=0.0013) and MMP13 (p=0.058) are possible predictive markers of ICS. The markers of IR and ICS presented here could, if confirmed in a clinical setting, guide clinicians in the choice of treatment and thus give a more individualized and effective therapy for patients with HNSCC

Predictive Markers of Treatment Resistance in Head and Neck Squamous Cell Carcinoma

Head and neck cancer is a common malignancy with approximately 600 000 new cases yearly. Disappointingly, the overall survival has not increased over the last decades. The concept of personalized medicine, i.e. to treat every patient with an individually planned treatment regime has gathered increased interest, but requires the establishment of novel biomarkers that can predict treatment response. The aim of this thesis is to propose novel predictive single markers or combinations of markers of response to radiation, cisplatin and cetuximab. The general methodology is to evaluate common differences of cell lines resistant to radiation, cisplatin or cetuximab compared to sensitive counterparts. In paper I, we analysed the expression of 14 proteins involved in growth control and/or apoptosis by western blot and related them to intrinsic radiosensitivity (IR) in nine cell lines. No factor had a significant correlation to IR on its own. A combination of EGFR, survivin, Bak, Smad4, and Hsp70 had the best correlation to IR (R=0.886, p=0.001). Additionally, we analysed the presence of p53 mutations in the cell lines. All cell lines had at least one missense, splice site or loss of transcript mutation. To be able to combine protein expression and presence of p53 mutations we created a system designated the number of negative points (NNP). With this system we could extract that expression of EGFR, survivin, and p53 missense or splice site mutations had the best correlation to IR (R=0.990, p<0.001). In paper II we conducted a gene expression microarray analysis of three cell lines, from which common deregulations in two cisplatin resistant cell lines was compared to a cisplatin sensitive cell line. From a bioinformatic approach of gene ontology and molecular network analysis, we defined a transcriptional profile of 20 genes. Finally, key findings were analysed in a larger panel of cell lines, where high MMP-7 expression correlated with higher cisplatin resistance. Paper III compared 4 cell lines with high IR to a radiosensitive equivalent. Using a similar bioinformatic approach as paper II, we established a transcriptional profile of 14 genes. Analysis in a larger panel of cell lines revealed that FN1 expression predicts higher IR. Paper IV establishes the cetuximab sensitivity of 35 cell lines of which 12 were resistant and five were sensitive to cetuximab. After whole genome gene copy number analysis of five cetuximab resistant and five cetuximab sensitive cell lines, and verification of key findings in a larger cell line panel, the results show that the amplification of the YAP1 gene is coupled to cetuximab resistance. In summary, this thesis proposes a number of novel markers of resistance to radiation, cisplatin, and cetuximab which could influence treatment choice in the future, following verifications in primary tumor material

Intracellular distribution of amyloid beta peptide and its relationship to the lysosomal system

Abstract Background Amyloid beta peptide (Aβ) is the main component of extraneuronal senile plaques typical of Alzheimer’s disease (AD) brains. Although Aβ is produced by normal neurons, it is shown to accumulate in large amounts within neuronal lysosomes in AD. We have recently shown that under normal conditions the majority of Aβ is localized extralysosomally, while oxidative stress significantly increases intralysosomal Aβ content through activation of macroautophagy. It is also suggested that impaired Aβ secretion and resulting intraneuronal increase of Aβ can contribute to AD pathology. However, it is not clear how Aβ is distributed inside normal neurons, and how this distribution is effected when Aβ secretion is inhibited. Methods Using retinoic acid differentiated neuroblastoma cells and neonatal rat cortical neurons, we studied intracellular distribution of Aβ by double immunofluorescence microscopy for Aβ40 or Aβ42 and different organelle markers. In addition, we analysed the effect of tetanus toxin-induced exocytosis inhibition on the intracellular distribution of Aβ. Results Under normal conditions, Aβ was found in the small cytoplasmic granules in both neurites and perikarya. Only minor portion of Aβ was colocalized with trans-Golgi network, Golgi-derived vesicles, early and late endosomes, lysosomes, and synaptic vesicles, while the majority of Aβ granules were not colocalized with any of these structures. Furthermore, treatment of cells with tetanus toxin significantly increased the amount of intracellular Aβ in both perikarya and neurites. Finally, we found that tetanus toxin increased the levels of intralysosomal Aβ although the majority of Aβ still remained extralysosomally. Conclusion Our results indicate that most Aβ is not localized to Golgi-related structures, endosomes, lysosomes secretory vesicles or other organelles, while the suppression of Aβ secretion increases intracellular intra- and extralysosomal Aβ.</p

Intracellular distribution of amyloid beta peptide and its relationship to the lysosomal system.

Background Amyloid beta peptide (Aβ) is the main component of extraneuronal senile plaques typical of Alzheimer’s disease (AD) brains. Although Aβ is produced by normal neurons, it is shown to accumulate in large amounts within neuronal lysosomes in AD. We have recently shown that under normal conditions the majority of Aβ is localized extralysosomally, while oxidative stress significantly increases intralysosomal Aβ content through activation of macroautophagy. It is also suggested that impaired Aβ secretion and resulting intraneuronal increase of Aβ can contribute to AD pathology. However, it is not clear how Aβ is distributed inside normal neurons, and how this distribution is effected when Aβ secretion is inhibited. Methods Using retinoic acid differentiated neuroblastoma cells and neonatal rat cortical neurons, we studied intracellular distribution of Aβ by double immunofluorescence microscopy for Aβ40 or Aβ42 and different organelle markers. In addition, we analysed the effect of tetanus toxin-induced exocytosis inhibition on the intracellular distribution of Aβ. Results Under normal conditions, Aβ was found in the small cytoplasmic granules in both neurites and perikarya. Only minor portion of Aβ was colocalized with trans-Golgi network, Golgi-derived vesicles, early and late endosomes, lysosomes, and synaptic vesicles, while the majority of Aβ granules were not colocalized with any of these structures. Furthermore, treatment of cells with tetanus toxin significantly increased the amount of intracellular Aβ in both perikarya and neurites. Finally, we found that tetanus toxin increased the levels of intralysosomal Aβ although the majority of Aβ still remained extralysosomally. Conclusion Our results indicate that most Aβ is not localized to Golgi-related structures, endosomes, lysosomes secretory vesicles or other organelles, while the suppression of Aβ secretion increases intracellular intra- and extralysosomal Aβ

Investigation of a sub boundary layer vortex generator for the control of separation in boundary layer-shock wave interaction

It is well known that in transonic flows, shQtk waves are fonned over the wings of aircraft. Depending on the strength of the shock wave and the state of the boundary layer, a region of boundary layer separation can occur downstream of the shock. This separation can lead to drastic changes in the flow over the wing which in tum can h~ad to an increase in drag, reduction of lift and buffeting. The aim of this investigation is to assess the potential of sub-boundary layer devices (Sub Boundary Vortex Generators, SBVG) to control a nonnal shock wave/ boundary layer interaction. The experiments have been perfonned at a nominal Mach number of 1.4 and a fre~strcam Reynolds mm1ber of 16x 106 pcr Uii.it length. Detr.ih;d measurements of a fully developed flat plate turbulent boundary layer were used to assess the perfonnance of 8 different SBVG configurations. The SBVG perfonnance was assessed by comparing flow before separation and after the reattachment. Mean flow data such as static and surface total pressure distributions, boundary layer total pressure and velocity profile, surface oil flow visualisation and schlieren method were used in evaluating the perfonnance of SBVGs. The experimental results indicate that the optimum SBVG for the current flow condition is a pair of Tetrahedral Vortex Generator with 30mm length with base and· height dimensions of 3mm by 3mm, which the height is 40% of the boundary layer thickness. The leading and trailing edge of this configuration were 18mm and 3 mm correspondingly.EThOS - Electronic Theses Online ServiceGBUnited Kingdo