A pesar de que el uso del cannabis y el alcohol como sustancias psicoactivas es muy antiguo y que su uso como drogas recreacionales está muy extendido, los mecanismos a través de los cuales producen sus efectos psicoactivos se han empezado a conocer hace relativamente poco tiempo. En la presente tesis se estudia como afectan distintos tratamientos sistémicos, tanto con etanol como con distintos compuestos cannabinoides, simultáneamente sobre la síntesis de las distintas monoaminas en diferentes regiones cerebrales de rata. Además, se analizó como afectaban estos tratamientos a los distintos componentes de la vía de señalización intracelular de las MAPK en la corteza frontal de rata. Se realizaron distintos tratamientos agudos con estos compuestos así como tratamientos a más largo plazo (crónicos) y además se estudiaron estos parámetros durante el llamado síndrome de abstinencia que aparece una vez que se detiene esta administración crónica.

Affinity proteins are invaluable tools in biotechnological and medical applications. This thesis is about combinatorial protein engineering principles for the generation of novel affinity proteins to purify mouse immunoglobulin, detect a potential cancer marker protein or inhibit a cell proliferation pathway. In a first study, ribosome display was for the first time applied to the selection of so-called affibody molecules, including the design of a ribosome display gene cassette, initial test enrichment experiments and the selection of binders against murine IgG1. One of the selected binders (ZMAB25) showed a highly selective binding profile to murine IgG1, which was exploited in the recovery of two different mouse monoclonal IgG1 antibodies from a bovine immunoglobulin-containing background. Ribosome display was further applied to the selection of affibody molecules binding to SATB1, a suggested marker protein for metastasizing adenocarcinoma. The study also included the selection of VHH antibody fragments from a naïve gene repertoire displayed on phage. Binders from both classes of protein scaffolds could be isolated that selectively recognized SATB1 but not its close homologue SATB2, and were used to detect endogenous SATB1 in Jurkat cells by immunofluorescence microscopy. The well-established phage display technology was used to select affibody molecules binding to H-Ras and Raf-1, both involved in the mitogen-activated protein kinase (MAPK) pathway and playing a central role in the control of cell proliferation, survival and differentiation. An isolated affibody molecule denoted ZRAF322 was found to selectively bind to Raf-1 and inhibit the interaction between H-Ras and Raf-1 in vitro. In a continued effort, ribosome display was applied to the affinity maturation of the ZRAF322 variant in a novel approach, based on repetitive cycles of diversification by error-prone PCR of the entire affibody gene and ribosome display selection, mimicking the principles of natural evolution. The method involved a monitoring of the progress of evolution and variants of ZRAF322 with 13- to 26-fold improved affinities were obtained, that contained different combinations of single or double amino acid substitutions in either previously randomized or framework positions. Implications of the substitutions for binder stability and selectivity were also investigated, showing that a higher affinity could be associated with a lower thermal melting point and that affinity-improved variants showed uncompromised binding selectivity to the hRaf-1 target. / QC 20110506

No description available.

Dissertation (Ph.D.)--University of South Florida, 2006. / Includes vita. Includes bibliographical references (leaves 166-187). Also available online.

Pancreatic cancer is the 4th leading cause of cancer related death in the United States with a median survival time of less than 6 months. Pancreatic ductal adenocarcinoma (PDAC) accounts for greater than 85% of all pancreatic cancers, and is marked by early and frequent mutation of the KRAS oncogene, with activating KRAS mutations present in over 90% of PDAC. To date, though, targeting activated KRAS for cancer treatment has been very difficult, and targeted therapies are currently being sought for the downstream effectors of activated KRAS. Activation of KRAS stimulates multiple signaling pathways, including the MEK-ERK and PI3K-AKT signaling cascades, but the role of downstream effectors in pancreatic tumor initiation and progression remains unclear. I therefore used primary pancreatic ductal epithelial cells (PDECs), the putative cell of origin for PDAC, to determine the role of specific downstream signaling pathways in KRAS activated pancreatic tumor initiation. As one third of KRAS wild type PDACs harbor activating mutations in BRAF , and KRAS and BRAF mutations appear to be mutually exclusive, I also sought to determine the effect of activated BRAF (BRAF V600E ) expression on PDECs and the signaling requirements downstream of BRAF. I found that both KRAS G12D and BRAF V600E expressing PDECs displayed increased proliferation relative to GFP expressing controls, as well as increased PDEC survival after challenge with apoptotic stimuli. This survival was found to depend on both the MEK-ERK and PI3K-AKT signaling cascades. Surprisingly, I found that this survival is also dependent on the IGF1R, and that activation of PI3K/AKT signaling occurs downstream of MEK/ERK activation, and is dependent on signaling through the IGF1R. Consistent with this, I find increased IGF2 expression in KRAS G12D and BRAF V600E expressing PDECs, and show that ectopic expression of IGF2 rescues survival in PDECs with inhibited MEK, but not PI3K. Finally, I showed that the expression of KRAS G12D or BRAF V600E in PDECs lacking both the Ink4a/Arf and Trp53 tumor suppressors is sufficient for tumor formation following orthotopic transplant of PDECs, and that IGF1R knockdown impairs KRAS and BRAF-induced tumor formation in this model. In addition to these findings within PDECs, I demonstrate that KRAS G12D or BRAF V600E expressing tumor cell lines differ in MEK-ERK and PI3K-AKT signaling from PDECs. In contrast to KRAS G12D or BRAF V600E expressing PDECs, activation of AKT at serine 473 in the KRAS G12D or BRAF V600E expressing tumor cell lines does not lie downstream of MEK, and only the inhibition of PI3K alone or both MEK and the IGF1R simultaneously results in loss of tumor cell line survival. However, inhibition of MEK, PI3K, or the IGF1R in KRAS G12D or BRAF V600E expressing tumor cell lines also resulted in decreased proliferation relative to DMSO treated cells, demonstrating that all three signaling cascades remain important for tumor cell growth and are therefore viable options for pancreatic cancer therapeutics.

No description available.

The study commences with a brief overview of the history of marriage and specifically of marriage in community of property with reference to marital power. The unique ex lege consequences of marriage in community of property is comprehensively discussed. The Constitutional Court decision in Harksen v Lane determined the test for unconstitutionality. The test for unconstitutionality is discussed with specific reference to the Bill of Rights. The Constitutional Court's decision in Volks v Robinson is critically evaluated as the Court propounded the so-called "choice argument" in terms of which people purposefully decide to marry instead of cohabiting and therefore the law may accord certain benefits to married people which are not available to unmarried life partners. The Constitutional Court decisions in Van der Merwe v RAF as well as its consequences are discussed. It concluded that section 18(b) of the Matrimonial Property Act constituted unjustifiable discrimination between spouses married in community of property and those married out of community of property and the said section was therefore declared unconstitutional. The law of insolvency in respect of the joint estate of spouses married in community of property is investigated. Freedom of testation and case law relating thereto is considered briefly. The study concludes with the submission that the common law provision that separate assets of a spouse in a marriage in community of property form part of the joint insolvent estate even if a testator expressly determined in his will that a bequest will not form part of the joint estate of a beneficiary, amounts to unfair discrimination and is unconstitutional. t is submitted that the principle unfairly discriminates between spouses married in community of property and those married out of community of property on the ground of marital status. / LLM (Estate Law), North-West University, Potchefstroom Campus, 2015

The study commences with a brief overview of the history of marriage and specifically of marriage in community of property with reference to marital power. The unique ex lege consequences of marriage in community of property is comprehensively discussed. The Constitutional Court decision in Harksen v Lane determined the test for unconstitutionality. The test for unconstitutionality is discussed with specific reference to the Bill of Rights. The Constitutional Court's decision in Volks v Robinson is critically evaluated as the Court propounded the so-called "choice argument" in terms of which people purposefully decide to marry instead of cohabiting and therefore the law may accord certain benefits to married people which are not available to unmarried life partners. The Constitutional Court decisions in Van der Merwe v RAF as well as its consequences are discussed. It concluded that section 18(b) of the Matrimonial Property Act constituted unjustifiable discrimination between spouses married in community of property and those married out of community of property and the said section was therefore declared unconstitutional. The law of insolvency in respect of the joint estate of spouses married in community of property is investigated. Freedom of testation and case law relating thereto is considered briefly. The study concludes with the submission that the common law provision that separate assets of a spouse in a marriage in community of property form part of the joint insolvent estate even if a testator expressly determined in his will that a bequest will not form part of the joint estate of a beneficiary, amounts to unfair discrimination and is unconstitutional. t is submitted that the principle unfairly discriminates between spouses married in community of property and those married out of community of property on the ground of marital status. / LLM (Estate Law), North-West University, Potchefstroom Campus, 2015

Dissertation (Ph.D.)--University of South Florida, 2008. / Title from PDF of title page. Document formatted into pages; contains 181 pages. Includes bibliographical references.

Dissertation (Ph.D.)--University of South Florida, 2009. / Title from PDF of title page. Document formatted into pages; contains 155 pages. Includes vita. Includes bibliographical references.