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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.
11

Biologia da formiga urbana Monomorium floricola Jerdon (Hymenoptera, Formicidae)

Solis, Daniel Russ. January 2011 (has links)
Orientador: Odair Correa Bueno / Banca: Ana Eugênia de Carvalho Campos / Banca: Mohamed Ezz El-Din Mostafa Habib / Banca: Edilberto Gianotti / Banca: Ana Yoshi Harada / Resumo: Monomorium floricola é uma espécie cosmopolita, adaptada ao meio urbano, que ocasiona incômodos em residências e hospitais. Poucos estudos foram efetuados com esta espécie e para o melhor conhecimento desta formiga, que possa ser utilizado em programas de manejo de pragas, o presente estudo teve como objetivo: analisar a interação com outras formigas urbanas; estudar o comportamento alimentar; descrever a morfologia externa das larvas e adultos reprodutores; verificar possíveis causas para o surgimento de anomalias nas formas reprodutoras; descrever o trato digestório; analisar a tolerância térmica das operárias; e verificar alguns fatores que poderiam interferir na fecundidade das rainhas virgens. As operárias de M. floricola se mostraram mais ofensivas em seu território e defensivas em outros territórios, com o comportamento sendo dependente da espécie de formiga com o qual interage. Com relação ao forrageamento: as substâncias açucaradas foram mais atrativas do que as gordurosas, as operárias despenderam mais tempo na coleta de substâncias açucaradas mais concentradas, e preferiram alimentos em maior quantidade e mais próximas ao ninho. As larvas de M. floricola se diferenciam das outras espécies do gênero, por apresentarem uma maior diversidade de pêlos e terem um número diferente de sensilas nos palpos. Os adultos reprodutores foram descritos com um maior detalhamento, fator importante para analisar com uma maior exatidão as formas anômalas. As anomalias não são causadas pelo choque térmico ou por bactérias simbiontes. O trato digestório das duas espécies de Monomorium apresentou algumas particularidades: a presença de espinhos no papo, e o número de túbulos de Malpighi e papilas retais não variaram entre as castas e idades. As operárias de M. floricola apresentaram uma alta tolerância para temperaturas frias, mas não para as quentes, quando... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Monomorium floricola is a cosmopolitan urban, and a worldwide pest in homes and hospitals. Few studies were directed with this species. With the objective of adding useful information for pest control programs, the present study aimed at analyzing: the interaction of these ants with other species when foraging for food; morphology of immature and adult reproductive forms; possible causes for the appearance of anomalous reproductive forms; internal anatomy of the digestive system; the tolerance of workers to different temperatures; different traits affecting the fecundity of virgin queens. Workers proved more defensive when foraging in enemy or neutral territory, and more aggressive when at their own territory. Their reaction towards alien ants was dependent upon their species. Sugary substances were more attractive than fatty foods, and workers spent more time collecting more concentrated sugary liquids, and give preference to foods at higher amounts and nearer to the nest entrance. Larvae of M. floricola were different from other Monomorium species by their greater diversity of types of body hairs, and by their number of mouthpart sensilla. Reproductive adults were described in richness of details, as we needed parameters to detect the anomalous forms. The appearance of anomalous forms is apparently not caused by temperature variations or by the presence of symbiotic bacteria. The digestive system of adults of M. floricola and M. pharaonis were unique, e.g. by their having spines in the crop and fixed number of Malpighian tubules and rectal pads among specimens of different castes and ages. Workers of M. floricola were tolerant to cold temperatures, but not to high temperatures, in comparison with tested species M. pharaonis and T. bicarinatum. Larvae and workers proved to interfere in the fecundity of virgin queens. We hope the finds of the present study will be of use in improving pest... (Complete abstract click electronic access below) / Doutor
12

Analyse zur Rolle von pflanzlichen Wirkstoffen und Histondeacetylase-Inhibitoren auf Wachstumsfaktoren und deren Signalwege in Prostatakarzinomzellen / Analysis of the role of herbal agents and histone deacetylase inhibitors on growth factors and their signaling pathways in prostate cancer cells

Witt, Daria 23 January 2013 (has links)
Das Prostatakarzinom (PCa) ist die am häufigsten diagnostizierte Krebsneuerkrankung bei Männern in Deutschland sowie die dritthäufigste Ursache krebsbedingter Sterbefälle. Die Therapiemöglichkeiten für das PCa sind sehr beschränkt und mit erheblichen Nebenwirkungen verbunden. Daher wurden in dieser Arbeit neue Therapieansätze verfolgt: zum einen wurde das Phytoöstrogen Tectorigenin (TG) und zum anderen der Histon-Deacetylase-Inhibitor (HDI) Valproinsäure (VPA) auf die jeweilige Wirksamkeit gegen das PCa untersucht. Das Phytoöstrogen Tectorigenin wird aus dem Gesamtextrakt von Belamcanda chinensis-Rhizomen isoliert. Dieser Gesamtextrakt wurde zunächst in PCa-Zellen in vitro getestet. Sowohl in den humanen PCa-Zellen LNCaP als auch in den murinen PCa-Zellen 2E, die aus dem Prostatatumor einer Maus des TRAMP-(transgenic adenocarcinoma of mouse prostate) Mausmodells neu etabliert wurden, konnte eine Inhibition der Zellproliferation sowie eine Veränderung der Expression ausgewählter PCa-relevanter Gene detektiert werden. Anschließend wurde eine Microarray-Analyse durchgeführt, bei der einige differentiell exprimierte Gene nach der Behandlung der humanen LNCaP-Zellen mit Tectorigenin identifiziert werden konnten. Neben einer Reihe von Androgen-induzierten Genen traten u.a. der IGF-IR (insulin-like growth factor I receptor) und PSA (prostate specific antigen) auf. In vivo-Studien in TRAMP-Mäusen konnten zudem eine langsamere Progression des PCa nach Behandlung mit Tectorigenin zeigen. In den in vivo-Studien an subkutanen LNCaP-Tumoren im Nacktmaus-Modell konnte sowohl ein vermindertes Tumorgewicht als auch eine verminderte Tumorgröße nach der Behandlung der Mäuse mit Tectorigenin beobachtet werden. Im zweiten Teil dieser Arbeit wurde die Wirkung des HDI VPA auf PCa-Zellen untersucht. Funktionell konnte eine erhöhte Acetylierung des Histons 3 an Lysin 9 sowie eine Verringerung der Zellproliferation, -migration und -invasion nach der Behandlung der primären PCa-Zellen 2E mit VPA gezeigt werden. Molekular konnten einige differentielle Genexpressionen nach der Behandlung der 2E-Zellen mit VPA detektiert werden. Es konnte z.B. eine Abnahme der Androgenrezeptor-Expression, eine Zunahme der Expression des proapoptotischen Proteins Bim sowie eine Verringerung der Expression von Foxo1 und Gsk3β gezeigt werden. Weiterhin wurde eine Deregulation von Zellzyklus- und Angiogenese-relevanten Genen wie z.B. Cdkn1a, Cdk4, Vegfa und Hif1α beobachtet. Des Weiteren wurden Kandidatengene aus einer früheren Microarray-Analyse untersucht. Für alle sieben untersuchten Kandidatengene wurde die differentielle Genexpression nach der Behandlung der 2E-Zellen mit VPA sowohl konzentrations- als auch zeitabhängig mittels quantitativer real time PCR bestätigt. Für die verstärkt exprimierten Gene konnte ein Zusammenhang mit einer erhöhten Acetylierung des Promotorbereichs der jeweiligen Gene nach VPA-Behandlung dargestellt werden. Das Kandidatengen Cyclin D2 wurde für weiterführende Untersuchungen ausgewählt. Als einziges Mitglied der D-Typ-Cycline lag Cyclin D2 nach VPA-Behandlung verstärkt exprimiert vor. Diese Re-Expression konnte auch durch die Behandlung mit HDIs verschiedener Wirkstoffklassen hervorgerufen werden. Die Untersuchung der PCa-Zelllinien PC-3, DU145 und LNCaP nach VPA-Behandlung zeigte ebenfalls, wie bei den primären PCa-Zellen 2E, eine Re-Expression von Cyclin D2 sowie eine Inhibition der Proliferation. Nicht-maligne Zelllinien, die bereits eine hohe Basalexpression von Cyclin D2 aufweisen, veränderten durch VPA die Cyclin D2-Expression nicht und auch der Effekt auf die Zellproliferation war nur moderat vorhanden. Die Verringerung der Cyclin D2-Expression mittels siRNA in den murinen Fibroblastenzellen NIH/3T3 führte zu einem Anstieg der Zellproliferation. Dass Cyclin D2 im PCa einen Tumorsuppresor darstellt, zeigt auch die immunhistochemische Analyse von humanen PCa-Gewebeschnitten, bei der keine Expression von Cyclin D2 im PCa-Gewebe nachgewiesen werden konnte. In gesundem Prostatagewebe hingegen wurde Cyclin D2 in den proliferierenden Zellen exprimiert. Im Gegensatz dazu wurde Cyclin D1 im PCa-Gewebe stärker exprimiert als im gesunden Prostatagewebe. Schließlich wurden in vivo-Studien an TRAMP-Mäusen mit VPA-Gabe über das Trinkwasser durchgeführt. Es wurden drei verschiedene Versuchsgruppen untersucht. In der Überlebensstudie, welche VPA präventiv ab einem Alter von sechs Wochen erhielt, konnte ein höheres Überlebensalter, ein geringerer Tumoranteil sowie ein geringeres Tumorgewicht verzeichnet werden. Nach präventiver Gabe von VPA ab einem Alter von sechs Wochen bis zu einem Alter von 30 Wochen konnte kein Unterschied zwischen der VPA- und der Kontrollgruppe detektiert werden. In der Überlebensstudie nach therapeutischer Gabe von VPA ab einem Alter von 16 Wochen konnte ein höheres Überlebensalter und ein geringerer Tumoranteil, jedoch kein Unterschied im Tumorgewicht gezeigt werden.
13

Fenomén jménem PORTA / The Phenomenon named PORTA

Hanzlík, Lubomír January 2021 (has links)
(in English) This thesis aims to present Porta Music Festival as a cultural and social phenomenon of the second half of the 1980s in Czechoslovakia on the basis of archival sources, secondary literature and our questionnaire survey.
14

[pt] ABORDAGEM DE OTIMIZAÇÃO PARA UM PROBLEMA DE ROTEAMENTO E PROGRAMAÇÃO DE NAVIOS / [en] OPTIMIZATION APPROACH TO A SHIP ROUTING AND PROGRAMMING PROBLEM

LUCAS GERALDO DE RESENDE LOUZADA 04 May 2020 (has links)
[pt] A organização da operação do transporte marítimo pode ser descrita dentre três modelos: liner, industrial ou tramp. No setor de tramp, armadores buscam otimizar os lucros através de ganhos de capacidade e redução de custos, ao mesmo tempo em que atendem às demandas e às restrições colocadas pelos clientes, muitas vezes baseadas em contratos. O roteamento de navios se torna um tema relevante dado que disponibilidade e confiabilidade de datas são um grande diferencial, ainda mais no atual contexto de alta oferta de navios tramp no mercado e, consequentemente, fretes mais baixos. Assim, o objetivo desse trabalho é apresentar um modelo de programação inteira mista visando a maximização do lucro de viagens pertencentes a uma específica rota geográfica de uma empresa tramp. O problema trabalhado nessa dissertação é do tipo pick-up e delivery (coleta e entrega) com janelas de tempo, múltiplas cargas a bordo, frota heterogénea, cargas fracionadas entre navios, velocidades de navegação variáveis e termos de tempo de trânsito garantidos. Utilizando-se da otimização Branch-and-Bound, o modelo é comparado com programações mensal real feita de maneira empírica por profissionais experientes dessa empresa em que o modelo matemático gera soluções com reduções de até 7 por cento dos custos totais e desafiando paradigmas estabelecidos pelos programadores quando da realização do roteamento e programação dos navios. Tendo em vista tais resultados, o modelo se apresentou como oportunidade de implementação e melhoria do processo de programação dos navios e do nível de serviço junto aos clientes. / [en] The organization of the maritime transport operation can be defined among three models: liner, industrial or tramp. In the tramp sector, shipowners seek to optimize profits through capacity gains and cost savings, while meeting the demands and constraints placed by customers, often based on contracts. Vessel routing becomes as availability and reliability of dates is a great differential, especially in the current context of a high supply of tramp vessels in the market and, consequently, lower freight rates. Thus, the hereby objective is to present a mixed integer programming model aiming to maximize the profit of all voyages belonging to a specific geographical route of a tramp company. The problem solved with in this work can be defined as of pick-up and delivery with time windows, multiple cargoes on board, heterogeneous fleet, split loads, variable sailing speeds and guaranteed transit time terms. Using Branch-and-Bound optimization, the model is compared to actual monthly routing planning made empirically by experienced professionals of that company and the mathematical model generates solutions with reductions of up to 7 percent of total costs and challenging programmers established paradigms when routing and programming vessels. In view of these results, the model presented itself as an opportunity to be implemented and improve the vessel routing and planning process and level of service to customers.
15

The Cellular and Molecular Properties of Flavinoids in Prostate Cancer Chemoprevention

Haddad, Ahmed Qais 31 July 2008 (has links)
Flavonoids are a large class of dietary polyphenols that have emerged as candidate agents for chemoprevention in prostate cancer. Despite the large number of known flavonoids (over 9000), only a few have been studied in prostate cancer to date. The work presented in this thesis describes the identification of novel anti-proliferative flavonoids, their molecular effects on cell cycle and related proliferation and survival pathways, and their chemopreventive properties in a murine model of prostate carcinogenesis. We identified several novel flavonoids with potent anti-proliferative effects in human prostate cancer cells in vitro. Non-prostate cell lines were generally resistant to the effect of these flavonoids. Two of the most potent flavonoids identified, 2,2-dihydroxychalcone (DHC) and fisetin, induced S and G2 phase cell cycle arrest in LNCaP and PC3 prostate cancer cells. Gene expression studies employing oligonucleotide microarray demonstrated profound down-regulation in gene expression of 75 key cell cycle (predominantly G2 and M phase) genes by DHC and fisetin, and the enhanced expression of 50 stress-response genes with important roles in cell proliferation and survival. DHC and fisetin induced apoptosis, but not accelerated senescence, in prostate cancer cells. The chemopreventive effect of 4 flavonoids identified from the in vitro studies was examined in an autochthonous murine model of prostate cancer (TRAMP). Mice were administered diets supplemented with 1% DHC, 1% fisetin or a combination of flavonoids (0.25% DHC, 0.25% fisetin, 0.25% quercetin, 0.25% luteolin) for 32 weeks. We demonstrated a significant reduction in genitourinary weight, and a reduction in prostate cancer grade in mice administered 1% DHC and combination diets. Flavonoid supplementation was, however, associated with gastrointestinal toxicity in some mice. Liquid chromatography-mass spectrometry demonstrated the accumulation of high levels of flavonoid in the prostates of TRAMP mice. These findings lay the foundation for further studies of flavonoids in clinical chemoprevention trials.
16

The Cellular and Molecular Properties of Flavinoids in Prostate Cancer Chemoprevention

Haddad, Ahmed Qais 31 July 2008 (has links)
Flavonoids are a large class of dietary polyphenols that have emerged as candidate agents for chemoprevention in prostate cancer. Despite the large number of known flavonoids (over 9000), only a few have been studied in prostate cancer to date. The work presented in this thesis describes the identification of novel anti-proliferative flavonoids, their molecular effects on cell cycle and related proliferation and survival pathways, and their chemopreventive properties in a murine model of prostate carcinogenesis. We identified several novel flavonoids with potent anti-proliferative effects in human prostate cancer cells in vitro. Non-prostate cell lines were generally resistant to the effect of these flavonoids. Two of the most potent flavonoids identified, 2,2-dihydroxychalcone (DHC) and fisetin, induced S and G2 phase cell cycle arrest in LNCaP and PC3 prostate cancer cells. Gene expression studies employing oligonucleotide microarray demonstrated profound down-regulation in gene expression of 75 key cell cycle (predominantly G2 and M phase) genes by DHC and fisetin, and the enhanced expression of 50 stress-response genes with important roles in cell proliferation and survival. DHC and fisetin induced apoptosis, but not accelerated senescence, in prostate cancer cells. The chemopreventive effect of 4 flavonoids identified from the in vitro studies was examined in an autochthonous murine model of prostate cancer (TRAMP). Mice were administered diets supplemented with 1% DHC, 1% fisetin or a combination of flavonoids (0.25% DHC, 0.25% fisetin, 0.25% quercetin, 0.25% luteolin) for 32 weeks. We demonstrated a significant reduction in genitourinary weight, and a reduction in prostate cancer grade in mice administered 1% DHC and combination diets. Flavonoid supplementation was, however, associated with gastrointestinal toxicity in some mice. Liquid chromatography-mass spectrometry demonstrated the accumulation of high levels of flavonoid in the prostates of TRAMP mice. These findings lay the foundation for further studies of flavonoids in clinical chemoprevention trials.
17

Sex steroid and growth factor expression in prostates of transgenic mice exposed to dietary polyphenols

Cook, Leah. January 2007 (has links) (PDF)
Thesis (M.S.)--University of Alabama at Birmingham, 2007. / Title from PDF title page (viewed Jan. 29, 2010). Includes bibliographical references (p. 55-60).
18

Suppression of Carcinogenesis and Tumor Progression by an Energy Restriction-Mimetic Agent in Murine Models of Prostate Cancer

Berman-Booty, Lisa Danielle 12 July 2013 (has links)
No description available.
19

Chemopreventive Effects of Dietary Selenium and Soy Isoflavones in a Mouse Model of Prostate Cancer

Quiner, Trevor Elisha 30 June 2010 (has links) (PDF)
Prostate cancer is the most commonly diagnosed non-skin cancer in men and the second leading cause of cancer death in the United States. Prostate cancer, like many cancers, is a disease that generally requires a long period of time to develop and grow before it becomes detectable. This long period of latency makes prostate cancer a candidate for dietary chemoprevention. Soy and selenium (Se), are associated with a decreased risk of prostate cancer. We previously showed that high dietary intake of selenium (Se) and soy isoflavones decreased the expression of the androgen receptor (AR) and AR-regulated genes in the prostates of healthy rats. In this study we hypothesized that the downregulation of AR and AR-regulated genes would inhibit tumorigenesis in the transgenic adenocarcinoma of the mouse prostate (TRAMP) mouse. Mice were fed one of two stock diets with or without a supplement of Se in a 2 X 2 factorial design. The stock diets provided high or low dietary isoflavones. Mice were exposed to the diets from conception and sacrificed at 18 or 24 weeks of age. Prostate histopathology, urogenital tract (UGT) weight, serum IGF-1 levels, and the expression of AR and AR-regulated genes in the dorsolateral prostate was examined using quantitative PCR and Western blotting. Urogenital tract (UGT) weight was reduced compared to control in all dietary groups containing high Se, isoflavones, or both at 24 weeks (p<0.005). Dietary isoflavones delayed tumor progression and downregulated protein levels of AR, AR-regulated genes, and upregulated the protective FOXO1 and FOXO3a transcription factors. High dietary isoflavones also decreased the phosphorylation of the IGF-1R. The only main effect of Se was the upregulation of AKR1C14 the enzyme that deactivates 5&aplha;-DHT.This study identifies a previously unknown effect of isoflavones in the upregulation of FOXO expression and confirms previous studies of isoflavones' anticancer effects. Further research is needed to find a protective dose or form of Se and to elucidate the mechanism of isoflavones.
20

Exposure to Dietary Selenium and Soy Isoflavones in Utero Provides Greater Protection Against Prostate Cancer Risk Factors in TRAMP Mice than Exposure Beginning at 6 Weeks

Lindsay, Heather Schofield 04 June 2012 (has links) (PDF)
Prostate cancer is the second most commonly occurring cancer in men in the United States. Generally, an extended period of time is needed for a mutation to develop into a full scale tumor. Because of this long latency period, lifestyle and environmental factors, such as diet, may play an important role in the development and progression of the disease. Diet is one factor that has been implicated in the risk for developing prostate cancer. We previously showed that diets high in soy isoflavones and selenium (Se) decreased androgen receptor expression and expression of androgen regulated genes in healthy rat prostates. The purpose of this study was to determine whether treatment of soy isoflavones and/or supplemental Se provide chemopreventive effects in the Transgenic Adenocarcinoma of Mouse Prostate (TRAMP) model of prostate cancer, and whether the timing of the introduction of these nutrients determines protective effects. Male hemizygous C57/BL6 x FVB TRAMP mice were exposed to a diet high in isoflavones, a 4 mg/kg daily bolus of supplemental Se as methylselenocysteine (MSC), or the combination of high isoflavones and MSC starting at one of two time points: conception or 6 weeks of age, and were killed and dissected for prostate tissue, liver, and serum at either 4 weeks or 12 weeks of age (n per dietary treatment = 20: total mice = 240). Treatment with MSC resulted in decreased urogenital tract weight at 4 and 12 weeks. Treatment with MSC and isoflavones, both individually and as a combination, resulted in decreased androgen receptor expression, 5 alpha-reductase levels, and aromatase levels. The combination of MSC and a basal diet high in isoflavones resulted in decreased serum IGF-1 levels in 12 week TRAMP mice. Treatment from conception resulted in greater decreases in urogenital tract weight, 5 alpha-reductase expression, and aromatase expression than treatment from 6 weeks. This study demonstrated that in 12 week TRAMP mice, reductions in risk factors for prostate cancer by treatments of high isoflavones and supplemental Se are maximized by introduction to treatments at conception.

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