Submitted in part fulfillment for the Degree of Master of Technology: Biotechnology, Durban Institute of Technology, 2003. / Evidence suggests that the induction of tissue kallikrein, and the subsequently formed kinins, enhances proliferation of tumour cells because of their mitogenic property. Additionally, the kinin peptides are believed to promote the invasion of normal tissue by tumour cells. TGF-l is a potent inhibitor of the growth of renal epithelial cells, and is a classical anti-mitogen, which is central to many of its antiproliferative effects. No studies thus far have been performed, as to whether the proposed anti-mitogenesis ofTGF-1 has a regulatory effect on the cell proliferative action of kinins on renal epithelial and carcinoma cells. / M

Glucan is a natural product immunomodulator that has been reported to enhance early wound repair. The mechanism of glucan-stimulated wound repair was thought to be indirect via macrophage release of wound growth factors. However, recent data indicate that there are glucan-specific receptors on human fibroblasts that can modulate cellular function following interaction with the glucan ligand. In this study we examined the effect of glucan on activation of the transcription factors activator protein-1 (AP-1) and specificity protein-1 (Sp1) in normal human dermal fibroblasts. AP-1 and Sp1 are involved in the regulation of cytokine and procollagen genes. In addition, we evaluated the effect of glucan on wound growth factor and vascular endothelial growth factor (VEGF) mRNA expression in primary cultures of normal human dermal fibroblasts. Glucan (1 μg/ml) stimulated fibroblast AP-1 and Sp1 activation in a time-dependent manner, although the temporal kinetics varied between the two transcription factors. AP-1 binding activity was increased (p<0.05) at early time intervals (1, 2, 4, 8 and 12 h), while Sp1 nuclear binding activity was increased (p<0.05) at later time intervals (12, 24, 36 and 48 h). Glucan (1 μg/ml) stimulated fibroblast expression of neurotrophin 3 (NT-3), platelet derived growth factor A (PDGF-A), platelet derived growth factor B (PDGF-B), fibroblast growth factor acidic (aFGF), fibroblast growth factor basic (bFGF), transforming growth factor alpha (TGFα), transforming growth factor beta (TGFβ) and VEGF mRNA at 8 h.

Orientador: Cláudia Valéria Seullner Brandão / Resumo: O plasma rico em plaquetas (PRP) atua na reparação corneal e, quando aquecido, minimiza a reação imunológica local sem interferir nos níveis dos fatores de crescimento. O objetivo deste estudo clínico foi comparar o PRP autólogo (GP) com o alogênico aquecido (GA) no tratamento de ceratite ulcerativa em cães, bem como os seus efeitos clínicos. Para isso, foram utilizados 24 cães diagnosticados na rotina oftalmológica com ceratite ulcerativa, distribuídos aleatoriamente em dois grupos experimentais, um tratado utilizando-se colírio de PRP autólogo (n=11) e outro com colírio de PRP alogênico aquecido (n=13). Todos os animais foram avaliados no momento inicial do atendimento e após 3, 5, 10, 15 e 30 dias do tratamento. Foram analisadas as seguintes variáveis oftalmológicas: blefaroespasmo, secreção ocular, opacidade corneal, vascularização, fotofobia, hiperemia conjuntival, quemose, espessura corneal e o percentual de redução da úlcera de córnea. Não houve diferenças estatísticas entre os grupos considerando o tratamento utilizado e verificou-se redução no tempo de cicatrização da lesão com adequada reepitelização corneal, bem como diminuição da opacidade e dos sinais de inflamação. Concluiu-se que o PRP autólogo e alogênico aquecido em cães apresentam-se de forma equiparável, sendo uma excelente opção no tratamento adjuvante da ceratite ulcerativa. / Abstract: Platelet rich plasma (PRP) acts on corneal repair and, when heated, presents reduced local immune response without interfering in growth factor levels. This clinical trial aimed to compare the use of autologous PRP (AP) and heated allogeneic PRP (HP) in the treatment of ulcerative keratitis in dogs, as well as their clinical effects. For this purpose, 24 dogs were utilized from the routine with diagnosis of ulcerative keratitis, and randomly distributed into two experimental groups, one treated with autologous PRP eye drops (n=11) and the other with heated allogeneic PRP eye drops (n=13). All the animals were evaluated at the initial moment of attendance and after 3, 5, 10, 15 and 30 days of treatment. The ophthalmologic variables analyzed were: blepharospasm, ocular discharge, corneal opacity, vascularization, photophobia, conjunctival hyperemia, chemosis, corneal thickness, as well as the percentage of corneal ulcer reduction. There were no statistical differences between the groups as to the treatment utilized whereas there was verification of a reduction in the injury-wound-healing time with adequate corneal re-epithelialization, as well as diminution of opacity and of inflammation signs. It was concluded that autologous and heated allogenic PRP in dogs are comparable in efficacy and constitute an excellent option in the adjuvant treatment of ulcerative keratitis. / Mestre

Articular cartilage is a smooth, white connective tissue that covers and protects the ends of long bones to allow for a smooth, frictionless surface on which to glide for easy movement. Once the tissue is damaged, articular cartilage lacks a direct blood supply, which results in a limited ability to repair itself. This study explores the effect of the growth factor BMP-13 on the chondroinduction of primary human bone marrow-derived mesenchymal stem cells. The results demonstrate the limited ability of BMP-13 to exert a strong chondroinductive effect on human bone marrow-derived MSCs. However, the results do indicate that BMP-13 has the ability to sustain chondroinduction to a certain extent for up to 18 days following initiation by 3 days of exposure to TGF-β3. Results are encouraging for future work that involves growth factor influence on MSCs in articular cartilage tissue engineering.

No description available.

No description available.

The enzyme gamma-glutamyl transferase (GGT) is a multifunctional enzyme that participates in a number of metabolic processes, including the conversion of leukotriene C4 (LTC4) to leukotriene D4 (LTD4). LTD4 is necessary for normal myeloid proliferation and differentiation. We have examined the ability of hematopoietic growth factors (HGF) to induce GGT enzyme activity and mRNA content in a HGF-responsive cell line (KG-1). Incubation of KG-1 with recombinant human cytokines interleukin-1β (IL- 1β), interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), and tumor necrosis factor (TNF), but not interleukin-6 (IL-6), granulocyte colony-stimulating factor (G-CSF) or monocyte colony-stimulating factor (M-CSF), results in significant increases in GGT enzyme activity. The increases in GGT activity are both dose- and time-dependent. In response to IL-1. Increases in enzyme activity are seen by 6 hours and activity is maximal by 24 hours. GGT mRNA increases also occur and peak by 3 to 6 hours. These results indicate that induction of increases in GGT mRNA levels and enzyme activity occur in myeloid cells in response to HGFs. This induction, together with the requirement for LTD4 for normal granulopoiesis, supports a role for GGT in the cellular events occurring in myeloid cells in response to HGFs.

Water uptake by a single root of an onion plant (Allium cepa) was measured potentially before, during and following exposure of shoots to an external electric field (EEF). The field strength used was 9kV/m DC and AC (60-Hz) brought about a statistically significant increase (44-71%) in water uptake if the shoot chamber was at almost 100% humidity.

Cardiovascular disease (CVD) is the leading cause of death internationally. Efforts to decrease CVD death has been explored through stem cell technology, specifically organoid formation. Current cardiac organoid models lack the vascular networks for nutrient supply and maturation. In this study, pillar perfusion technology is used to fabricate cardiac organoids and induce vascularization via dynamic culturing and the addition of vascular promoting growth factors (GFs). In addition to this study, a millifluidic chip is engineered for shear stress application via flow simulations and experimental flow analysis. We successfully optimized the millifluidic chip to achieve fluid shear stress of 20mPa and validated through particle tracking velocimetry using 0.1um diameter beads under flow. The results of cardiac organoids displayed contraction and growth of endothelial cells (ECs) under dynamic flow with GFs. In addition, smooth muscle cells (SMCs) displayed growth via GFs in both dynamic and static culturing. Although vascular networks were not present in all conditions of this experiment, this thesis can serve a basis for searching other methods of inducing vascularization.

No description available.