Submitted by Karem Dantas (karem.c.dantas@gmail.com) on 2018-10-08T13:33:57Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Teorema de Pick.pdf: 18162866 bytes, checksum: b5924b5d514e4978acc23fddace5a5cb (MD5) / Approved for entry into archive by Marcos Roberto Gomes (mrobertosg@gmail.com) on 2018-10-08T14:49:39Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Teorema de Pick.pdf: 18162866 bytes, checksum: b5924b5d514e4978acc23fddace5a5cb (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-10-09T17:15:54Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Teorema de Pick.pdf: 18162866 bytes, checksum: b5924b5d514e4978acc23fddace5a5cb (MD5) / Made available in DSpace on 2018-10-09T17:15:54Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Teorema de Pick.pdf: 18162866 bytes, checksum: b5924b5d514e4978acc23fddace5a5cb (MD5) Previous issue date: 2018-06-20 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The purpose of this project is Pick’s Theorem, which is about of the calculation of simple polygons with vertices in the points of mesh grid at the plane. The theorem let us to calculate the area using counting, analyzing the points in the edge and the interior of the polygon at the mesh grid. We going to talk about a little bit of Georg Alexander Pick history, beyond the necessary observations to understand the theorem’s demonstration and complexity. At last, we going to show you Pick’s Theorem activities, in the Geoboard and on the GeoGebra software as didactic resources for classroom. / O foco deste trabalho é o Teorema de Pick. Esse teorema se refere ao cálculo de áreas de polígonos simples com vértices nos pontos de uma malha quadriculada no plano, o teorema permite calcular a área usando contagem, analisando os pontos do bordo e do interior do polígono em uma malha quadriculada. Apresentaremos um pouco da história de Georg Alexander Pick, além de observações necessárias para se compreender a demonstração do teorema e sua extensão. Finalmente mostramos atividades com o teorema de Pick no Geoplano e no software GeoGebra como recursos didáticos para a sala de aula.

Cholesterol is essential for many life processes, including correct development, fluidity of cell membranes, production of steroid hormones and bile acids, and is a major component of myelin. Smith-Lemli-Opitz Syndrome (SLOS) and Niemann-Pick disease type C (NPC) are devastating diseases and both involve dysregulation of cholesterol homeostasis. SLOS is caused by a defect in 7-dehydrocholesterol reductase (DHCR7), resulting in increased levels of 7-dehydrocholesterol (7DHC) and decreased levels of cholesterol. On the other hand, NPC is caused by defects in NPC1 or NPC2. These genes encode two lysosomal proteins that are responsible for the transport of cholesterol and other lipids out of lysosomes. Consequently, defects in these proteins results in accumulation of unesterified cholesterol within late endosomes/lysosomes. The severity ranges of both disorders are broad, and no or limited therapeutic options are available. This thesis aimed to establish the incidence and mechanisms behind SLOS and NPC in order to aid development of novel therapeutic interventions. Using a bioinformatics approach, <b>Chapter 2</b> showed that the estimated incidences of classical SLOS and NPC were similar to clinical reports. However, the analysis suggested that a late onset form of NPC1 could be more prevalent. <b>Chapter 3</b> investigated the behavioural phenotype of the SLOS Dhcr7^{T93M/&Delta;3-5} mouse model and it was found that some parallels could be drawn to the behaviour observed in SLOS patients. It also highlighted some defects in neuro-anatomy that could potentially explain certain cognitive defects. <b>Chapter 4</b> explored the suggestion of oxidative stress in the Dhcr7^{T93M/&Delta;3-5} mouse model. However, this study did not support a role for oxidative stress in this model. Genetic insights were generated via an RNAseq study on SLOS and NPC patient fibroblasts, which suggested that the WNT signalling pathway could play a role in the pathogenesis of SLOS. This pathway was also highlighted when the cells were treated with miglustat, the only approved therapy for NPC. However, the main pathway apparently affected by this drug in both SLOS and NPC was cell proliferation.

Niemann-Pick type C2 (NPC2) protein is a soluble protein that binds unesterified cholesterol. The protein helps transport unesterified cholesterol in tandem with the membrane protein Niemann-Pick type C1 (NPC1). Defects in either of proteins can cause Niemann-Pick type C disease (NPC), which results in the accumulation of unesterified cholesterol and lipids in the late endosome and lysosome. NPC is an autosomal recessive lysosomal storage disease affecting 0.35~2.20 per 100,000 people. Here we present the structural analysis of the human NPC2 glycoprotein, including expression, purification, functional analysis, homology modeling, and crystallographic studies. Human NPC2 was expressed from baculovirus-infected Trichoplusia ni (Tn5) insect cells. The construct contained a hexahistidine purification epitope tag, and the protein was purified using Nickel affinity column chromatography. The purified protein was used in binding studies with dehydroergosterol (DHE), showing that human NPC2 was functional. Using the structure of bovine NPC2, we made a homology model and mapped the human mutations onto the model. Some modeled proteins, such as the V30M and S67P variants, are unclear as to how they lead to disease, thus a structure of the human protein would be informative. Crystallization screens of human NPC2 were performed and led to crystals with a needle-like morphology, which diffracted to 4Å resolution. The structure of human NPC2 will be useful for understanding the mechanism of cholesterol binding and trafficking in cells, and to better understand the human metabolic disease NPC.

Two-neutron pick up reactions have been performed on targets of 149Sm and radioactive 151Sm using 18 MeV protons. The outgoing tritons from the 151Sm target were analyzed with a magnetic spectrograph at 16 angles between 6 degrees and 8 degrees. Unlike the two-neutron transfer data on neighbouring even-even targets, the angular distributions indicated l=o transitions to many levels in the final nucleus. Partial angular distributions for the 149Sm (p, t) 147Sm reaction were obtained, but showed only one strong l=o transition populating the 147Sm ground state. In addition, spectra from the 152Sm (p, t) reaction were measured at several angles in order to provide normalization to previous results. / Thesis / Master of Science (MSc)

A hipótese do presente estudo sugere que a baixa fertilidade de vacas Holandesas (Bos taurus) repetidoras de serviço (RS) está relacionada à baixa qualidade oocitária que, por sua vez, é associada ao quadro de resistência periférica a insulina (RPI). Ainda, a indução de lactação (IL) em vacas Holandesas (Bos taurus) RS pode reverter o quadro de RPI e, consequentemente, melhorar a qualidade oocitária e a produção in vitro de embriões (PIVE). Para testar a hipótese proposta, este estudo objetivou avaliar o efeito da fase da lactação e da gestação [Exp. 1], o efeito da secagem de RS [Exp. 2] e o efeito da IL [Exp. 3] sobre a RPI, a qualidade oocitária e a PIVE em vacas da raça Holandesa (Bos taurus). Nos três estudos foram realizados testes de tolerância à glicose (TTG) para avaliar a RPI através do perfil hormonal sérico de insulina e glicose. Além disso, avaliou-se o perfil bioquímico sérico e folicular e a qualidade oocitária através da PIVE. Verificou-se que, em resposta à infusão de 0,3mg glicose/kg PV, as vacas RS no final da lactação secretaram 53% mais insulina e captaram 40% menos de glicose quando comparadas as vacas no terço inicial de lactação (Exp 1). Esses achados são indicativos do estabelecimento do quadro de RPI nas vacas RS em lactação. Durante o período seco, as vacas RS secretaram 96% mais insulina e captaram 56% menos glicose que as vacas no terço inicial da lactação e as vacas RS em lactação, respectivamente (Exp. 2). Ainda, as vacas com lactação induzida secretaram 11% menos insulina e captaram a mesma quantidade de glicose que vacas paridas em fases semelhantes de lactação (Exp 3), demonstrando que o protocolo de IL foi eficiente em alterar o perfil metabólico, revertendo o quadro de RPI presente nas vacas RS. Nos Exp. 1, 2 e 3 foram verificadas maiores concentrações plasmática de triglicérides (TG; P &lt; 0,05), colesterol total (COL; P < 0,05) e LDL (P < 0,05) no soro sanguíneo em vacas RS quando comparadas com vacas no terço inicial de lactação. Durante o período seco (Exp. 2 e 3), observou-se incremento desses metabólitos, destacando aumento na concentração de TG (P < 0,05), COL (P < 0,05) e LDL (P < 0,05) plasmático em vacas secas quando comparadas as vacas em lactação [início e final (RS) da lactação]. No liquido folicular foram observadas variações no perfil bioquímico para COL e TG. Nos Exp. 1, 2 e 3, verificou-se que vacas RS possuem maior concentração de TG (P < 0,05) e COL (P < 0,05) no fluido folicular do que vacas no terço inicial de lactação. Contrariando a hipótese inicialmente proposta, as vacas RS em lactação e as vacas secas apresentaram maior taxa de blastocisto (P < 0,05) e número de blastocistos por OPU (P < 0,05) que as vacas no terço inicial de lactação (Exp. 1, 2 e 3). Através do perfil de insulina circulante em resposta ao TTG foi possível demonstrar o estabelecimento do quadro de RPI em vacas RS (P < 0,05). Além disso, constatou-se agravamento da RPI em vacas secas (P < 0,05). Esse quadro foi associado ao aumento do escore de condição corporal (P < 0,05) e do peso vivo (kg; P < 0,05) nas vacas RS. Em conclusão, não foi verificada associação negativa entre RPI, qualidade oocitária e PIVE em vacas Holandesas (Bos taurus) RS. Apesar da indução de lactação em vacas Holandesas (Bos taurus) RS alterar o metabolismo e diminuir o quadro de RPI, não foi verificado efetivo positivo na qualidade oocitária e na PIVE. / The hypothesis of the present study suggests that low fertility of repeat breeders (RB) Holstein (Bos taurus) cows is related to low oocyte quality, which is associated with peripheral insulin resistance (PIR). Also, induction of lactation (IL) in RB Holstein (Bos taurus) cows can revert PIR and, consequently, improve oocyte quality and in vitro embryo production (IVEP). In order to test the proposed hypothesis, the objective of this study was to evaluate the effect of phase of lactation and gestation [Exp. 1], effect of drying RB [Exp. 2] and effect of IL [Exp. 3] on PIR, oocyte quality and IVEP of Holstein (Bos taurus) cows. In all three studies, glucose tolerance tests (GTT) were performed to evaluate PIR through the serum hormonal insulin and glucose profile. In addition, we evaluated the serum and follicular biochemical profile and oocyte quality through IVEP. It was verified that, in response to a 0.3mg glucose/kg of body weight (BW), RB cows at the end of lactation secreted 53% more insulin and captured 40% less glucose when compared to cows in the initial third of their lactation (Exp. 1). These findings are indicative of the establishment of PIR in RB lactating cows. During the dry period, RB cows secreted 96% more insulin and captured 56% less glucose than cows in the initial third of their lactation and RB lactating cows, respectively (Exp. 2). Also, cows with induced lactation secreted 11% less insulin and captured the same amount of glucose than calved cows in similar lactation phase (Exp. 3), demonstrating that the IL protocol was efficient to alter the metabolic profile, reverting PIR present in RB cows. In Exp. 1, 2 and 3 higher plasmatic concentrations of triglycerides (TG; P<0.05), total cholesterol (COL; P<0.05) and LDL (P<0.05) were verified in the blood serum in RB cows when compared to cows in the initial third of their lactation. During the dry period (Exp. 2 and 3), we observed the increment of these metabolites, and a notable elevation of the plasmatic TG (P < 0.05), COL (P < 0.05) and LDL (P < 0.05) in dry cows when compared to lactating cows [beginning and end (RB) of lactation]. In the follicular fluid, it was possible to observe variations in the biochemical profile for COL and TG. In Exp. 1, 2 and 3, it was verified that RB cows have higher concentration of TG (P < 0.05) and COL (P < 0.05) in the follicular fluid than cows in the initial third of their lactation. Contrary to the initially proposed hypothesis, RB lactating cows and dry cows presented higher blastocyst rate (P<0.05) than cows in the initial third of lactation (Exp. 1, 2 and 3). Through the circulating insulin profile in response to the GTT it was possible to demonstrate the establishment of PIR in RB cows (P<0.05). Also, it was observed worsening of the PIR in dry cows (P<0.05). This condition was associated with an increase in body condition score (P<0.05) and BW (kg; P<0.05) in RB cows. In conclusion, no negative association between PIR, oocyte quality and IVEP was observed in RB Holstein (Bos taurus) cows. Although induction of lactation in RB Holstein (Bos taurus) cows altered the metabolism and reduced PIR, no positive effect was observed in oocyte quality and IVEP.

A hipótese do presente estudo sugere que a baixa fertilidade de vacas Holandesas (Bos taurus) repetidoras de serviço (RS) está relacionada à baixa qualidade oocitária que, por sua vez, é associada ao quadro de resistência periférica a insulina (RPI). Ainda, a indução de lactação (IL) em vacas Holandesas (Bos taurus) RS pode reverter o quadro de RPI e, consequentemente, melhorar a qualidade oocitária e a produção in vitro de embriões (PIVE). Para testar a hipótese proposta, este estudo objetivou avaliar o efeito da fase da lactação e da gestação [Exp. 1], o efeito da secagem de RS [Exp. 2] e o efeito da IL [Exp. 3] sobre a RPI, a qualidade oocitária e a PIVE em vacas da raça Holandesa (Bos taurus). Nos três estudos foram realizados testes de tolerância à glicose (TTG) para avaliar a RPI através do perfil hormonal sérico de insulina e glicose. Além disso, avaliou-se o perfil bioquímico sérico e folicular e a qualidade oocitária através da PIVE. Verificou-se que, em resposta à infusão de 0,3mg glicose/kg PV, as vacas RS no final da lactação secretaram 53% mais insulina e captaram 40% menos de glicose quando comparadas as vacas no terço inicial de lactação (Exp 1). Esses achados são indicativos do estabelecimento do quadro de RPI nas vacas RS em lactação. Durante o período seco, as vacas RS secretaram 96% mais insulina e captaram 56% menos glicose que as vacas no terço inicial da lactação e as vacas RS em lactação, respectivamente (Exp. 2). Ainda, as vacas com lactação induzida secretaram 11% menos insulina e captaram a mesma quantidade de glicose que vacas paridas em fases semelhantes de lactação (Exp 3), demonstrando que o protocolo de IL foi eficiente em alterar o perfil metabólico, revertendo o quadro de RPI presente nas vacas RS. Nos Exp. 1, 2 e 3 foram verificadas maiores concentrações plasmática de triglicérides (TG; P &lt; 0,05), colesterol total (COL; P < 0,05) e LDL (P < 0,05) no soro sanguíneo em vacas RS quando comparadas com vacas no terço inicial de lactação. Durante o período seco (Exp. 2 e 3), observou-se incremento desses metabólitos, destacando aumento na concentração de TG (P < 0,05), COL (P < 0,05) e LDL (P < 0,05) plasmático em vacas secas quando comparadas as vacas em lactação [início e final (RS) da lactação]. No liquido folicular foram observadas variações no perfil bioquímico para COL e TG. Nos Exp. 1, 2 e 3, verificou-se que vacas RS possuem maior concentração de TG (P < 0,05) e COL (P < 0,05) no fluido folicular do que vacas no terço inicial de lactação. Contrariando a hipótese inicialmente proposta, as vacas RS em lactação e as vacas secas apresentaram maior taxa de blastocisto (P < 0,05) e número de blastocistos por OPU (P < 0,05) que as vacas no terço inicial de lactação (Exp. 1, 2 e 3). Através do perfil de insulina circulante em resposta ao TTG foi possível demonstrar o estabelecimento do quadro de RPI em vacas RS (P < 0,05). Além disso, constatou-se agravamento da RPI em vacas secas (P < 0,05). Esse quadro foi associado ao aumento do escore de condição corporal (P < 0,05) e do peso vivo (kg; P < 0,05) nas vacas RS. Em conclusão, não foi verificada associação negativa entre RPI, qualidade oocitária e PIVE em vacas Holandesas (Bos taurus) RS. Apesar da indução de lactação em vacas Holandesas (Bos taurus) RS alterar o metabolismo e diminuir o quadro de RPI, não foi verificado efetivo positivo na qualidade oocitária e na PIVE. / The hypothesis of the present study suggests that low fertility of repeat breeders (RB) Holstein (Bos taurus) cows is related to low oocyte quality, which is associated with peripheral insulin resistance (PIR). Also, induction of lactation (IL) in RB Holstein (Bos taurus) cows can revert PIR and, consequently, improve oocyte quality and in vitro embryo production (IVEP). In order to test the proposed hypothesis, the objective of this study was to evaluate the effect of phase of lactation and gestation [Exp. 1], effect of drying RB [Exp. 2] and effect of IL [Exp. 3] on PIR, oocyte quality and IVEP of Holstein (Bos taurus) cows. In all three studies, glucose tolerance tests (GTT) were performed to evaluate PIR through the serum hormonal insulin and glucose profile. In addition, we evaluated the serum and follicular biochemical profile and oocyte quality through IVEP. It was verified that, in response to a 0.3mg glucose/kg of body weight (BW), RB cows at the end of lactation secreted 53% more insulin and captured 40% less glucose when compared to cows in the initial third of their lactation (Exp. 1). These findings are indicative of the establishment of PIR in RB lactating cows. During the dry period, RB cows secreted 96% more insulin and captured 56% less glucose than cows in the initial third of their lactation and RB lactating cows, respectively (Exp. 2). Also, cows with induced lactation secreted 11% less insulin and captured the same amount of glucose than calved cows in similar lactation phase (Exp. 3), demonstrating that the IL protocol was efficient to alter the metabolic profile, reverting PIR present in RB cows. In Exp. 1, 2 and 3 higher plasmatic concentrations of triglycerides (TG; P<0.05), total cholesterol (COL; P<0.05) and LDL (P<0.05) were verified in the blood serum in RB cows when compared to cows in the initial third of their lactation. During the dry period (Exp. 2 and 3), we observed the increment of these metabolites, and a notable elevation of the plasmatic TG (P < 0.05), COL (P < 0.05) and LDL (P < 0.05) in dry cows when compared to lactating cows [beginning and end (RB) of lactation]. In the follicular fluid, it was possible to observe variations in the biochemical profile for COL and TG. In Exp. 1, 2 and 3, it was verified that RB cows have higher concentration of TG (P < 0.05) and COL (P < 0.05) in the follicular fluid than cows in the initial third of their lactation. Contrary to the initially proposed hypothesis, RB lactating cows and dry cows presented higher blastocyst rate (P<0.05) than cows in the initial third of lactation (Exp. 1, 2 and 3). Through the circulating insulin profile in response to the GTT it was possible to demonstrate the establishment of PIR in RB cows (P<0.05). Also, it was observed worsening of the PIR in dry cows (P<0.05). This condition was associated with an increase in body condition score (P<0.05) and BW (kg; P<0.05) in RB cows. In conclusion, no negative association between PIR, oocyte quality and IVEP was observed in RB Holstein (Bos taurus) cows. Although induction of lactation in RB Holstein (Bos taurus) cows altered the metabolism and reduced PIR, no positive effect was observed in oocyte quality and IVEP.

In dieser Arbeit beleuchten wir die subzelluläre Lokalisation von Flotillin unter Einfluss von Cholesterin. Wir zeigen, dass die zelluläre Lokalisation abhängig vom Cholesterinniveau der Zelle ist. Eine Cholesterindepletion bringt Flotillin in die Plasmamembran, sowie umgekehrt eine Überversorgung mit Cholesterin Flotillin in cholesterinhaltige, endosomale Strukturen führt. Dabei ist die Umverteilung abhängig von der Integrität des Zytoskeletts. Außerdem zeigt die vorliegende Arbeit, dass die Umverteilung von Flotillin von der Plasmamembran hin zu endosomalen, intrazellulären Kompartimenten abhängig vom Vorhandensein von zwei putativen Cholesterinbindungs-/Interaktionsdomänen ist. Aus den gewonnenen Daten ergeben sich weiterhin Hinweise, dass Cholesterin an Flotillin gebunden in das späte Endosomen transportiert wird. In weiterführenden Versuchen unserer Gruppe zeigte sich, dass die exosomale Freisetzung von Cholesterin bei ansteigenden zellulären Cholesterinkonzentrationen erhöht wird und dass die exosomale Cholesterinfreisetzung von Flotillin abhängig ist. Die Daten deuten auf eine mögliche Rolle von Flotillin und Exosomen bei der zellulären Cholesterinhomöostase hin.

Bakgrund: En organisations olika avdelningar är ständigt i behov av rätt information vid rätt tillfälle. Information i realtid är av stor vikt för en distributör då deras överlevnad är beroende av kunden. Plockprocessen i ett lager hos ett företag utgör en stor kostnad och är en viktig aktivitet att förbättra för att bli mer lönsam och effektivare. Syfte: Syftet med studien är att skapa ett beslutsunderlag gällande implementering av ett digitalt verktyg för en manuell plockprocess samt ekonomisk aspekt och förändringsarbete. Det generella beslutsunderlaget ska kunna tillämpas av företag som agerar grossister inom distribution och som vill digitalisera plockprocessen för att få information i realtid. Metod: Studien omfattas av en kvalitativ forskningsmetod där fallstudie har utförts. Forskarna har tillämpat jämförande studie gällande det digitala verktygen. Empiri har samlats in genom snöbollsurval och använt strukturerade och semi- strukturerade intervjuer samt utfört observationer. Resultat: Studien har analyserat tre digitala verktyg utifrån Hall Mibas förutsättningar. Studien har analyserat de lämpliga verktygen utifrån ett finansiellt perspektiv med hjälp av en Pay-back kalkyl samt testat resultatet med en känslighetsanalys. En sammanställning av en möjlig implementeringsprocess har förklaras med hjälp av ASAP Roadmap och forskarna har utformat en checklista för företag att följa genom implementeringens gång.

M. Niemann-Pick Typ C (NPC) ist eine juvenile Demenz mit intrazellulärer Anreicherung von freiem Cholesterin, M. Alzheimer (AD) eine senile Demenz, die mit einem Polymorphismus im Gen des Cholesterintransportproteins Apolipoprotein E (ApoE) assoziiert ist. Bei beiden Erkrankungen treten im Gehirn zahlreiche neurofibrilläre Tangles (NFT), bestehend aus Protein Tau, auf. Es sollte mit einer für freies Cholesterin spezifischen Filipin-Färbung herausgefunden werden, ob sich bei beiden Erkrankungen der Cholesteringehalt Tangle-tragender Neurone von dem Tangle-freier unterscheidet. Zur Verfügung standen diverse Teile aus dem Zentralen Nervensystem von 5 NPC- und Gyri temporales superficiales von 9 AD-Fällen. In Material von 3 NPC-Fällen und 1 AD-Fall fanden sich intraneuronale, mit Tangles assoziierte Cholesterinakkumulationen. In 3 AD-Fällen fanden sich außerdem Cholesterinakkumulationen in Assoziation mit Senilen Plaques. Der Cholesteringehalt Tangle-tragender Neurone war in 6 Regionen der NPC-Fälle und in 3 AD-Fällen erhöht. Für alle Neuronenpaare der AD-Fälle insgesamt ergab sich ein erhöhter Cholesteringehalt des Tangle-tragenden Neurons. Cholesterinspeicherung im NPC-Hirn könnte über oxidativen Stress oder eine Veränderung der cholesterinabhängigen Signaltransduktion zur Tangle-Bildung führen. Argumente für die Unterstützung der Tangle-Bildung durch Cholesterin über oxidativen Stress und veränderte Signaltransduktion in AD werden angeführt. Diese Untersuchung erlaubt, neue Hypothesen zu gemeinsamen Mechanismen der Tangle-Entstehung in AD und NPC zu formulieren. / Niemann-Pick type C disease (NPC) is a juvenile dementia with intracellular accumulation of free cholesterol, whereas Alzheimer s disease (AD) is a senile dementia associated with a gene polymorphism of a cholesterol transport protein, apolipoprotein E (apoE). In both conditions, there are abundant neurofibrillary tangles (NFT) in brain, consisting of protein tau. This study addresses the issue whether cholesterol content of tangle-bearing neurons is the same compared to tangle-free neurons, in both diseases. For this purpose, staining with the free cholesterol-specific fluorochrome filipin was used. Several CNS tissue specimen of 5 NPC cases and superior temporal gyri of 9 AD cases were available. In 3 NPC cases and 1 AD case, intraneuronal cholesterol accumulation were found associated with neurofibrillary tangles. Furthermore, cholesterol accumulations were found associated with senile plaques in 3 AD cases. Cholesterol content of tangle-bearing neurons was increased in 6 regions of the NPC cases and in 3 AD cases. For all neurons analysed in AD, the tangle-bearing neuron showed more cholesterol than the adjacent tangle-free neuron. Cholesterol storage in NPC brain could lead to neurofibrillary degeneration by enhancing oxidative stress or by alterating cholesterol-dependent signal transduction. Cholesterol accumulation in AD neurons could lead to neurofibrillary degeneration by the same mechanisms. This study allows the creation of new hypotheses concerning common mechanisms of neurofibrillary degeneration in both Niemann-Pick type C and Alzheimer s diseases.

Sphingolipide sind eine wichtige Klasse von Lipiden, die nicht nur als Strukturmoleküle von Bedeutung sind sondern auch in Signaltransduktionsprozessen eine wichtige Rolle spielen. Insbesondere die Sphingolipidmetaboliten Ceramid, Sphingosin und Sphingosin-1-phosphat sind an zellulären Prozessen wie Differenzierung, Apoptose, Proliferation und Inflammation beteiligt. Sphingomyelinasen üben daher als katabole Enzyme des Sphingolipidstoffwechsels eine wichtige Funktion aus. Die vorliegende Arbeit befasst sich mit der Expression und Reinigung der rekombinanten humanen sauren Sphingomyelinase sowie ausgewählter varianter Formen des Enzyms, die verschiedene Subtypen der Niemann-Pick-Erkrankung widerspiegeln. Die Kinetiken und weitere Parameter der erhaltenen Enzyme wurden nach Michaelis-Menten bestimmt. Durch Gabe der rekombinanten Enzyme zu metabolisch radiomarkierten (NPA -/-) Fibroblasten wurde die Stimulation des Sphingolipidmetabolismus nachverfolgt. Mittels FT-IR Spektroskopie gelang die Bestimmung und Quantifizierung von Sekundärstrukturelementen im Wildtypenzym und den varianten Formen. Darüber hinaus wurde in SPR-Messungen die biomolekulare Interaktion der sauren Sphingomyelinase mit dem Krebstherapeutikum Siramesin untersucht. Siramesin, welches als Inhibitor der sauren Sphingomyelinase wirkt, induziert selektiv in Krebszellen den lysosmalen Zelltod. In diesem Zusammenhang wurde die saure Sphingomyelinase als potentielles Zielmolekül für Krebstherapien identifiziert. / Sphingolipids are an important class of lipid molecules. Beyond their structural role, they also serve as bioactive signalling entities. Sphingolipid metabolites like ceramide, sphingosine and sphingosine-1-phosphate are involved in many cellular processes including differentiation, apoptosis, proliferation, inflammation and intracellular trafficking. In this context, sphingomyelinases are of special interest. The present work focuses on the expression and purification of recombinant human acid sphingomyelinase and selectively chosen variant forms of the enzyme, representing prominent Niemann-Pick disease types. Subsequently the biochemical parameters of all obtained enzymes were determined by Michaelis-Menten kinetics. In order to asses the stimulation of sphingolipid metabolism metabolically radiolabeled (NPA -/-) cells were treated with the recombinant enzymes. Based on FT-IR spectroscopy, structural components of the acid sphingomyelinase and its variants, were determined and quantified. Furthermore SPR-experiments were performed to analyse the biomolecular interaction of immobilized acid sphingomyelinase and the anticancer agent siramesine. Siramesine acts as an inhibitor on acid sphingomyelinase, thereby triggering cancer-specific lysosomal cell death. In this context the human acid sphingomyelinase was identfied as a target for cancer therapy.