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Multi-Scale Modelling of Vector-Borne DiseasesMathebula, Dephney 21 September 2018 (has links)
PhD (Mathematics) / Department of Mathematics and Applied Mathematics / In this study, we developed multiscale models of vector-borne diseases. In general, the transmission
of vector-borne diseases can be considered as falling into two categories, i.e. direct transmission
and environmental transmission. Two representative vector-borne diseases, namely; malaria
which represents all directly transmitted vector-borne diseases and schistosomiasis which represents
all environmentally transmitted vector-borne diseases were studied. Based on existing
mathematical modelling science base, we established a new multiscale modelling framework
that can be used to evaluate the effectiveness of vector-borne diseases treatment and preventive
interventions. The multiscale models consisted of systems of nonlinear ordinary differential
equations which were studied for the provision of solutions to the underlying problem of the
disease transmission dynamics. Relying on the fact that there is still serious lack of knowledge
pertaining to mathematical techniques for the representation and construction of multiscale
models of vector-bone diseases, we have developed some grand ideas to placate this gap. The
central idea in multiscale modelling is to divide a modelling problem such as a vector-bone disease
system into a family of sub-models that exist at different scales and then attempt to study
the problem at these scales while simultaneously linking the sub-models across these scales.
For malaria, we formulated the multiscale models by integrating four submodels which are: (i)
a sub-model for the mosquito-to-human transmission of malaria parasite, (ii) a sub-model for
the human-to-mosquito transmission of malaria parasite, (iii) a within-mosquito malaria parasite
population dynamics sub-model and (iv) a within-human malaria parasite population dynamics
sub-model. For schistosomiasis, we integrated the two subsystems (within-host and between-host
sub-models) by identifying the within-host and between-host variables and parameters associated
with the environmental dynamics of the pathogen and then designed a feedback of the variables
and parameters across the within-host and between-host sub-models. Using a combination of analytical
and computational tools we adequately accounted for the influence of the sub-models in
the different multiscale models. The multiscale models were then used to evaluate the effectiveness
of the control and prevention interventions that operate at different scales of a vector-bone
disease system. Although the results obtained in this study are specific to malaria and schistosomiasis,
the multiscale modelling frameworks developed are robust enough to be applicable to
other vector-borne diseases. / NRF
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Characterization of Amino Acid Transporters : Transporters expressed in the central nervous system belonging to the Solute Carrier family SLC38Hellsten, Sofie Victoria January 2016 (has links)
In cells and organelles transporters are responsible for translocation of amino acids, sugars and nucleotides among others. In the central nervous system (CNS), amino acid transporters can function as neurotransmitter transporters and nutrient sensors. The Solute carrier (SLC) superfamily is the largest family of transporters with 395 members divided in 52 families. The system A and system N amino acid transporter family, SLC38, consists of 11 members, SNAT1-11 (SLC38A1-11). The members are expressed in the brain, exclusively in neurons or astrocytes and some in both. Amino acid signaling is mainly regulated via two pathways, the amino acid responsive (AAR) pathway and the mechanistic/mammalian target of rapamycin complex 1 (mTORC1) pathway. These pathways regulate the protein synthesis in opposite directions depending on the amino acid availability. SLC38 members along with other SLCs have been identified to participate in these pathways. In paper I, the regulation of SLC genes after complete amino acid starvation in mouse hypothalamic cells have been studied with microarray and we found that 47 SLC genes were significantly altered at five hours of starvation. Interestingly, we found that Slc38a1 and Slc38a7 were upregulated along with the known starvation responding gene, Slc38a2. A complementary starvation study for the SLC38 genes was performed using primary mouse embryonic cortex cells. We found that Slc38a1, Slc38a2, Slc38a5, Slc38a6 and Slc38a8 were upregulated while Slc38a3, Slc38a7 and Slc38a11 were downregulated. Three members from the SLC38 family, SNAT8 (paper IV), SNAT9 (paper III) and SNAT10 (paper II) have been histologically characterized in mouse brain and all these transporters are exclusively neuronal. SNAT8 and SNAT10 were also functionally characterized and shown to be transporters for alanine and glutamine among others. SNAT8 was shown to mediate sodium dependent transport and was classified to system A. SNAT10 was shown to be a sodium independent bidirectional transporter and displayed characteristics for system A and N. SNAT9 is a lysosomal component of the Ragulator-Rag complex which senses amino acid availability and activates mTORC1. In paper III we also found that Slc38a9 gene expression was upregulated following starvation and downregulated following high-fat diet in mouse brain.
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Bat as the animal origin of SARS-CoV and reservoir of diverse coronavirusesLi, Sze-ming, Kenneth., 李思銘. January 2009 (has links)
published_or_final_version / Microbiology / Doctoral / Doctor of Philosophy
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A DLTS study of copper indium diselenideDjebbar, El-hocine January 1998 (has links)
No description available.
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An Organic Electrochemical Transistor for Printed Sensors and LogicNilsson, David January 2005 (has links)
Conducting polymers entered the research field in late 70´s and efforts aimed at achieving printed electronics started a decade later. This thesis treats printable organic electrochemical transistors (OECT). Some conjugated polymers can be switched between a high conducting and a low conducting state in an electrochemical cell. In this thesis, the work carried out using poly(3,4-ethylenedioxythiophene) (PEDOT) as the active material in an electrochemical transistor is reported. The electrochemical transistors, presented, can be designed into a bi-stable and dynamic mode of operation. These transistors operates at voltages below 2V and current on/off ratios are typically 5000, but 105 have been reached. The transistor device can be built up from all-organic materials using common printing techniques such as with screen-printing. The bi-stable transistor can be combined with an electrochromic (EC) display cell to form a smart pixel circuit. Combining several of these smart pixels yield an actively addressed cross-point matrix display. From this an all-organic active matrix display printable on paper has been achieved. The OECT, combined with a resistor network was successfully used in inverter and logic circuits. One important feature of these organic electrochemical devices is that both ions and electrons are used as the charge (signal) carriers. This is of particular interest and importance for chemical sensors. By combining a proton-conducting electrolyte (Nafion®) that changes its conductivity upon exposure to humidity, a simple OECT humidity sensor was achieved. This proves the use of this OECT as the ion-to-electron transducer.
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Vliv plastifikace na reologické vlastnosti oligoestru kyseliny mléčné a glykolové větveného dipentaerythritolem / Effect of plasticization on rheological properties of oligoester of lactic acid and glycolic acid branched with dipentaerythritolBílková, Klára January 2014 (has links)
CHARLES UNIVERSITY IN PRAGUE Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical technology Name of the student: Klára Bílková Title of diploma thesis: Influence of plastification on rheological properties of oligoester of lactic acid and glycolic acid branched with dipentaerythritole Consultant: PharmDr. Eva Šnejdrová, Ph.D. The aim of this diploma thesis was the study of rheological properties of the oligoester of DL-lactic and glycolic acids branched with 1% of dipenthaerythritol (1D) and plasticized with 6 various plasticizers in increasing concentrations. Theoretical part was devoted to fundamentals of rheology and measurements of viscosity using rotational viscometers. It describes basic types and constructions of rotational rheometers and summarizes basic facts about bioadhesion and use of rheological method for assessment of bioadhesion. There were prepared matrices from oligoester 1D and plasticizers in concentrations of 20 %, 30 % and 40 % in the experimental part. These plasticizers were tested: ethyl pyruvate, ethyl salicylate, methyl salicylate, triacetin, tributyrin and triethyl citrate. Rheological properties were examinated at 37 řC using spindle viscometer and at 37 řC and 50 řC using rotational rheometer. Rheograms were used to characterize flow properties of tested...
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Aktuální otázky regulace mezinárodní letecké přepravy / Topicas issues of the regulation of international air transportPichlerová, Lucie January 2014 (has links)
Topical issues of the regulation of international air transport This thesis with current issues of legal regulation of international carriage by air, with a focus on the air carrier's liability. After the introductory chapter follows the second chapter which delas with aviation law and specifics of this legal branch. It further discusses the different methods of legal relations in civil aviation and recommends the most appropriate options of treatment. The third chapter summarizes the concept of responsibility in private law with a focus on recodification in Czech private law in 2014. The findings are applied to international and regional regulation of air carrier's liability, which is discussed in the next part of the thesis . The following fourth chapter deals with the liability of the air carrier on the international level. Firstly summarizes the historical development that preceded the adoption of legal rules in aviation law and in the next section discusses two important international documents - the Warsaw Convention and the Montreal Convention . In the section that deals with the Montreal Convention is focused on practical issues, mainly the interpretation of various terms used by the Montreal Convention . The author tries to hold uniform structure for all legal documents which are discussed...
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Liberace acikloviru z mukoadhezivních matric / Acyclovir release from mucoadhesive matricesŠišáková, Lenka January 2014 (has links)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Student: Lenka Šišáková Supervisor of Diploma thesis: PharmDr. Eva Šnejdrová, Ph.D. Title of Diploma thesis: Aciclovir release from mucoadhesive matrices The aim of this diploma thesis was the study of the mucoadhesive parameters of plasticized oligoester of lactic acid and glycolic acid and 3% mannitol as a branching monomer. Knowledge of dissolution testing of drug release from dosage form, principal theories and mechanisms of mucoadhesion and mucoadhesion testing of adhesive formulation is described in theoretical part. Matrices formed from terpolymer of D,L-lactic acid, glycolic acid branched with mannitol and 5 % aciclovir were examined in the experimental part. Triethylcitrate (TEC), ethylpyruvate (EP), methylsalicylate (MS) and ethylsalicylate (ES) were used as plasticizers. Dissolution test has been done. Hydrated mucin from porcine stomach was used as a base. Phosphate-citrate buffer pH 7.4 was used as a dissolution medium. Dissolution was defined as a quantity of released aciclovir in to the dissolution medium after 15, 30, 60 and 90 minutes. The quantity of the released aciclovir was defined by a spectrophotometry. In 90 minutes was released 43 % of aciclovir from the matrice...
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Miopatia miotubular: diagnóstico molecular e aconselhamento genético em famílias brasileiras / Myotubular myopathy: molecular diagnosis and genetic counselling in Brazilian familiesSouza, Lucas Santos e 17 December 2018 (has links)
A miopatia miotubular é uma doença genética congênita que afeta a musculatura esquelética e respiratória, causada por mutações no gene MTM1. Apresenta padrão de herança recessivo ligado ao cromossomo X e frequência estimada de 1/50.000 meninos nascidos vivos. O diagnóstico é geralmente realizado através de biopsia muscular, com presença de fibras pequenas com núcleo central, predominância de fibras do tipo I, concentração de miofibrilas na periferia da fibra e região central ocupada por acúmulos de mitocôndrias e glicogênio. O quadro clínico é bastante grave, com manifestação clínica no período neonatal e óbito nos primeiros meses, ou ano de vida. Os pacientes apresentam hipotonia e fraqueza muscular generalizadas, dificuldade de alimentação, ptose palpebral, oftalmoplegia, hérnia inguinal e criptorquidia. Mulheres portadoras das mutações são geralmente assintomáticas, mas diversos casos de heterozigotas sintomáticas têm sido relatados. Pacientes com miopatias congênitas estruturais vem sendo estudados nos últimos 20 anos no Centro de Pesquisa do Genoma Humano e Células Tronco (CPGH-CEL) da Universidade de São Paulo (USP). Atualmente, em razão do avanço das tecnologias de análise molecular do DNA, como o sequenciamento de nova geração (NGS - Next Generation Sequencing), o diagnóstico tem se tornado cada vez mais preciso. No presente trabalho, pacientes de 12 famílias estudadas no CEGH-CEL foram submetidos à triagem mutacional, utilizando técnica de NGS. Onze mutações foram identificadas (c.109 C>T; c.139_142 delAAAG; c.706 A>T; c.1010 G>A, c.1181 A>G, c.1262 G>A, c.1354 -1 G>C, c.1465_1465delC, c.1467 +1 G>A, c.1528 A>T; c.1528 A>T); entre elas 5 já descritas como patogênicas e 6 são novas. Em duas famílias, foram identificadas 4/8 e 2/4 mulheres portadoras apresentando algum nível de manifestação clínica. A análise de desvio de inativação do X revelou desvio aleatório em pelo menos 4 das heterozigotas manifestantes. Além disso, adicionando os casos deste trabalho aos relatados na literatura, a taxa de penetrância da doença foi estimada em 30% em mulheres heterozigotas, o que é compatível com um padrão de penetrância incompleta e poderia explicar a alta frequência de mulheres manifestantes. Uma análise de exomas foi realizada a fim de identificar possíveis genes modificadores que explicassem a variabilidade clínica observada. Foi identificada uma região de 4,2 Mb contendo genes contíguos no cromossomo 19 que pode estar relacionado à modulação do fenótipo / Myotubular myopathy is a rare congenital muscle genetic disease, caused by mutations in the MTM1 gene. With a X-linked recessive inheritance, the disease affects 1/50.000 living born males. The clinical picture is characteristic and very severe, with manifestation in the neonatal period, including generalized hypotonia and muscle weakness, feeding difficulty, palpebral ptosis, ophthalmoplegia, inguinal hernia, and cryptorchidism. Most affected die in the first few months or year of life, and those who survive often depend on care and assistance to perform activities of daily living, as well as require mechanical ventilation and enteral nutrition. Females carrying the mutations are generally asymptomatic, but several cases of symptomatic heterozygotes have been reported, compared to the low frequency of manifesting carriers in other X-recessive diseases. Patients with structural congenital myopathies have been studied in the last 20 years at the Human Genome and Stem Cell Research Center (HUG-CELL) at the University of São Paulo (USP). The diagnosis of myotubular myopathy is usually made with muscle biopsy findings, with small fibers with central nuclei, the predominance of type I fibers, the concentration of myofibrils in the periphery of the fiber and central region occupied by accumulations of mitochondria and glycogen. More recently, with the advancement of DNA molecular analysis technologies, such as Next Generation Sequencing (NGS), the diagnosis has become increasingly accurate. In the present study, patients from 12 families studied in the HUG-CEL were submitted to mutation screening using NGS techniques. Eleven mutations were identified (c.109 C> T; c.139_142 delAAAG; c.706 A> T; c.1010 G> A, c.1181 A> G, c.1262 G> A, c.1354-1 G> C, c.1465_1465delC, c.1467 +1 G> A, c.1528 A> T; c.1528 A> T); among them 6 are novel. In two families, 4/8 and 2/4 female carriers were identified, presenting some level of clinical manifestation. Inactivation skewing analysis of the X chromosome revealed random inactivation in at least 4 of the manifesting carriers. In addition, joining the cases of this work to those reported in the literature, the disease penetrance rate was estimated to be 30% in heterozygous women, which is compatible with an incomplete penetrance pattern and could explain the high frequency of manifesting females. An exome analysis was performed to identify possible modifying genes that explain the observed clinical variability. A region of 4,2 Mb containing contiguous genes was identified on chromosome 19 that may be related to phenotype modulation
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Preparação, caracterização e avaliação do potencial citotóxico in vitro de carreadores lipídicos nanoestruturados funcionalizados com folato encapsulando quercetina em células de câncer de bexiga / Preparation, characterization and cytotoxic potential evaluated in bladder cancer cells of nanostructured lipid carriers functionalized with folate encapsulated quercetinSilva, Letícia Bueno 05 December 2016 (has links)
Câncer de bexiga (CB) é a segunda doença mais prevalente do trato urinário. Atualmente as principais terapias para o CB apresentam baixa eficácia, altas taxas de recorrência e vários efeitos adversos. Assim, avalia-se o potencial de novas moléculas para a terapia do CB. Quercetina (QT) é um flavonóide com propriedades inibidora da proliferação celular e apoptótica que são interessantes para o tratamento do câncer, porém é um composto instável e fotossensível, o que inviabiliza sua administração na forma livre. Desta forma, o encapsulamento da QT em carreadores lipídicos nanoestruturados (CLN) funcionalizados com folato (CLN-F) pode ser um sistema efetivo de entrega de QT em células de CB que poderá superar os desafios da terapia intravesical do CB. O encapsulamento da QT pode aumentar a estabilidade da QT, sua permeação pelo urotélio, internalização em células tumorais, seu tempo de residência na bexiga e sua eficácia farmacológica. Os objetivos deste trabalho foram preparar, caracterizar e avaliar a citotoxicidade de QT livre e encapsulada em CLN e CLN-F em células de CB. O CLN e CLN-F foram preparados pelo método de emulsão e sonicação. A funcionalização do CLN foi realizada pela reação do estabilizante Pluronic F68 com folato (PF68F). Esta funcionalização foi avaliada por espectroscopia de ressonância magnética Nuclear (RMN) unidimensional de 1H. Os CLNs foram caracterizados quanto ao diâmetro, índice de polidispersão (PdI), potencial zeta (PZ), cristalinidade, eficiência de encapsulamento (EE) e morfologia. Além disso, foi avaliado o perfil de liberação da QT, a atividade antioxidante e a citotoxicidade da QT livre e encapsulada. A funcionalização foi confirmada pelos espectros de RMN que apresentaram sinais atribuídos ao PF68 e ao folato. O diâmetro, PdI e o PZ dos CLN foram 176,5 nm, 0,124 e -11,4 mV, respectivamente. O CLN-F apresentou 197,9 nm de diâmetro, 0,160 de PdI e -17,5mV de PZ. O encapsulamento da QT não alterou significativamente estes parâmetros para ambas as partículas. Obteve-se uma alta eficiência de encapsulamento da QT, para os dois carreadores (~98%), devido, provavelmente, ao baixo valor de índice de recristalização (~28) dos CLNs. Os CLN apresentam forma esférica, estabilidade por 330 dias e um perfil de liberação sustentada da QT. O IC50 do CLN-F-QT (83,4 ?g/mL) foi menor que o IC50 do CLN-QT (94,9 ?g/mL) provavelmente devido ao aumento da internalização causada pela funcionalização das partículas com folato. Os CLN-QT e CLN-F-QT apresentaram alta atividade antioxidante. Os resultados obtidos sugerem que o CLN-F-Q é um sistema com potencial para a futura terapia do CB, pois apresenta tamanho menor que 200 nm, baixo PdI, alta estabilidade, EE e atividade antioxidante, liberação sustentada além de ser citotóxico para as células RT4. / Bladder cancer (BC) is the second most prevalent tumor of urinary tract. Currently the main BC therapies have low effectiveness, high recurrence rate and several adverse effects. Thus, new molecule have been investigate to CB therapy. Quercetin (QT) is a flavonoid with interesting properties for cancer therapy such as inhibition of cancer cell proliferation and apoptosis. However, QT is an unstable and photosensitive compound. Therefore, QT encapsulated in nanostructure lipid carriers (NLC) functionalized with folate (F-NLC) might be an alternative targeting system of QT for tumor cell and can be strategy to overcome intravesical CB therapy challenges. The QT encapsulation can improve QT stability, increase its permeation in the urothelium and uptake in tumor cells, increase retention time in the bladder and enhancing its pharmacological efficacy. Aims of this study were preparation, characterization of NLC-QT and F-NLC-QT and cytotoxic evaluation of these particles in BC cells. NLC and F-NLC were prepared by ultrasonication method. NLC were funcionalized by conjugated between surfactant Pluronic and folate (PL68F). This conjugation was characterized by proton nuclear magnetic resonance spectroscopy (NMR). The particles were characterized regarding to size, polydispersity index (PdI), zeta potential (ZP), crystallinity, encapsulation efficiency (EE) and morphology. Furthermore, stability, release profile, cytotoxicity and antioxidant activity of QT encapsulated or not in NLC, were evaluated. RMN spectrums confirmed the PF68 functionalization, exhibiting peaks attributed to PF68 and folate. Size, PdI and ZP of NCL were respectively 176.5 nm, 0.124 and -11.4, whereas F-NLC showed 197.9 nm of size, 0.160 of PdI and ZP of -17.5mV. The QT encapsulation did not affect these physical parameters. Low values of crystalization index (~28) might promote high EE of quercetin (~98%). NLC shows spherical shape, sustained release profile of QT and were stable for 330 days. IC50 of NLC-QT (87.4 ?g/mL) was smaller thanthe IC50 of F-NLC-QT (94.9 ?g/mL). This difference might be explained by the increase of NLC uptake by endocytosis mediated by folate receptor. NLC-QT and F-NLC-QT showed high antioxidant activity. Therefore, our results suggest that QT-F-NLC is a carry system with potential for future BC therapy that show size smaller than 200 nm, low PdI, high long-term stability, high EE and antioxidant activity, sustained release and cytotoxic to CB cells (RT4).
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