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High-Frequency Irreversible Electroporation (H-FIRE) optimization for the treatment of highly invasive cells beyond the tumor marginLatouche, Eduardo L. 19 June 2016 (has links)
Irreversible electroporation (IRE) is a non-thermal ablation technique that allows for eradication of unresectable tumors in a minimally invasive procedure. While IRE will preferentially kill larger cells over smaller ones, it does not discriminate between cells with larger and small nuclei. Given that one of the hallmarks of cancer cell morphology is larger, more abundant nuclei, our team set out to explore the possibility of preferentially targeting this physical and geometrical characteristic. / Master of Science
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Evaluation of Norovirus Persistence on Farm and Agriculturally-relevant EnvironmentsFallahi Marvast, Sara 05 March 2012 (has links)
Human norovirus (NoV) causes gastroenteritis worldwide and has been associated with a number of produce related outbreaks. The design of effective inactivation and prevention procedures requires an understanding of virus survival in environments applicable to the production and processing of fresh produce. To evaluate the extent of NoV risk from farm to fork, the survival of murine norovirus (MNV), a surrogate for human NoV, was studied on stainless steel disks, soil and in bottled water for 42 days and on lettuce for 15 days in the laboratory. Stability experiments were then conducted on farm during one lettuce planting/harvest cycle, for 4 weeks. MNV stability was tested at room temperature in the laboratory or under ambient conditions on the farm. A one log reduction in virus titre was achieved after 30 days in water, 4 days on lettuce, 15 days on stainless steel disks, 12 days on loamy and sandy soil. For farm testing, infectious virus was recovered from both soil and lettuce on the day of inoculation. Although infectious virus was not recovered at later time points, the viral genomes were detected for up to four weeks. The observed long-term persistence of NoV, under both laboratory and field conditions, provides valuable information for developing risk assessments and control procedures to limit the possibility for NoV transmission in the food supply.
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Evaluation of Norovirus Persistence on Farm and Agriculturally-relevant EnvironmentsFallahi Marvast, Sara 05 March 2012 (has links)
Human norovirus (NoV) causes gastroenteritis worldwide and has been associated with a number of produce related outbreaks. The design of effective inactivation and prevention procedures requires an understanding of virus survival in environments applicable to the production and processing of fresh produce. To evaluate the extent of NoV risk from farm to fork, the survival of murine norovirus (MNV), a surrogate for human NoV, was studied on stainless steel disks, soil and in bottled water for 42 days and on lettuce for 15 days in the laboratory. Stability experiments were then conducted on farm during one lettuce planting/harvest cycle, for 4 weeks. MNV stability was tested at room temperature in the laboratory or under ambient conditions on the farm. A one log reduction in virus titre was achieved after 30 days in water, 4 days on lettuce, 15 days on stainless steel disks, 12 days on loamy and sandy soil. For farm testing, infectious virus was recovered from both soil and lettuce on the day of inoculation. Although infectious virus was not recovered at later time points, the viral genomes were detected for up to four weeks. The observed long-term persistence of NoV, under both laboratory and field conditions, provides valuable information for developing risk assessments and control procedures to limit the possibility for NoV transmission in the food supply.
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Evaluation of Norovirus Persistence on Farm and Agriculturally-relevant EnvironmentsFallahi Marvast, Sara 05 March 2012 (has links)
Human norovirus (NoV) causes gastroenteritis worldwide and has been associated with a number of produce related outbreaks. The design of effective inactivation and prevention procedures requires an understanding of virus survival in environments applicable to the production and processing of fresh produce. To evaluate the extent of NoV risk from farm to fork, the survival of murine norovirus (MNV), a surrogate for human NoV, was studied on stainless steel disks, soil and in bottled water for 42 days and on lettuce for 15 days in the laboratory. Stability experiments were then conducted on farm during one lettuce planting/harvest cycle, for 4 weeks. MNV stability was tested at room temperature in the laboratory or under ambient conditions on the farm. A one log reduction in virus titre was achieved after 30 days in water, 4 days on lettuce, 15 days on stainless steel disks, 12 days on loamy and sandy soil. For farm testing, infectious virus was recovered from both soil and lettuce on the day of inoculation. Although infectious virus was not recovered at later time points, the viral genomes were detected for up to four weeks. The observed long-term persistence of NoV, under both laboratory and field conditions, provides valuable information for developing risk assessments and control procedures to limit the possibility for NoV transmission in the food supply.
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Evaluation of Norovirus Persistence on Farm and Agriculturally-relevant EnvironmentsFallahi Marvast, Sara January 2012 (has links)
Human norovirus (NoV) causes gastroenteritis worldwide and has been associated with a number of produce related outbreaks. The design of effective inactivation and prevention procedures requires an understanding of virus survival in environments applicable to the production and processing of fresh produce. To evaluate the extent of NoV risk from farm to fork, the survival of murine norovirus (MNV), a surrogate for human NoV, was studied on stainless steel disks, soil and in bottled water for 42 days and on lettuce for 15 days in the laboratory. Stability experiments were then conducted on farm during one lettuce planting/harvest cycle, for 4 weeks. MNV stability was tested at room temperature in the laboratory or under ambient conditions on the farm. A one log reduction in virus titre was achieved after 30 days in water, 4 days on lettuce, 15 days on stainless steel disks, 12 days on loamy and sandy soil. For farm testing, infectious virus was recovered from both soil and lettuce on the day of inoculation. Although infectious virus was not recovered at later time points, the viral genomes were detected for up to four weeks. The observed long-term persistence of NoV, under both laboratory and field conditions, provides valuable information for developing risk assessments and control procedures to limit the possibility for NoV transmission in the food supply.
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Optimization of Cell Culture Procedures for Growing Neural Networks on Microelectrode ArraysSanta Maria, Cara L. 12 1900 (has links)
This thesis describes the development of an optimized method for culturing dissociated, monolayer neuronal networks from murine frontal cortex and midbrain. It is presented as a guidebook for use by cell culture specialists and laboratory personnel who require updated and complete procedures for use with microelectrode array (MEA) recording technology. Specific cell culture protocols, contamination prevention and control, as well common problems encountered within the cell culture facility, are discussed. This volume offers value and utility to the rapidly expanding fields of MEA recording and neuronal cell culture. Due to increasing interest in determining the mechanisms underlying Parkinson's disease, the newly developed procedures for mesencephalon isolation and culture on MEAs are an important research contribution.
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Evalutation of Human Platelet Lysate in NK Cell CultureWilliamson, Elizabeth 01 January 2020 (has links)
Natural Killer (NK) cells can recognize and lyse a large variety of tumor cells and have been of interest as a potential cancer treatment option. Our group has developed a particle-based NK cell expansion method that utilizes plasma membrane particles (PM-particles) derived from K562 cells genetically engineered to express membrane bound IL21 and 41BBL(K562-mbIL21-41BBL), two proteins that stimulate growth and activity of NK cells. This method selectively expands highly cytotoxic NK cells > 400-fold in 14 days of culture. Currently NK cells are expanded in vitro using Fetal Bovine Serum (FBS) as a serum-supplement to promote cell growth. While effective, the use of animal products is not preferred in cell cultures grown for clinical purposes. This project tested Human Platelet Lysates (HPL) as a potential replacement for FBS in NK cell culture. NK cells were expanded using PM21-particle based expansion method with either FBS or HPL as supplements. Their growth characteristics, phenotype and functionality were assessed and compared. Results of this study determined that HPL is a viable option to replace FBS in NK cell culture for clinical applications, as there was no significant difference between the two serum supplements.
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Obtenção de anticorpo monoclonal anti-dengue tipo 2 em diferentes meios e sistemas de cultivoZanatta, Aline Stelling January 2009 (has links)
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Previous issue date: 2009 / Fundação Oswaldo Cruz. Instituto de Tecnologia em Imunobiológicos. Rio de Janeiro, RJ, Brasil / Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil. / Desde o trabalho de Köhler e Milstein (1975), hibridomas tem sido cultivados para
obtenção de anticorpos monoclonais com finalidade de uso em pesquisa, diagnóstico e
terapia. O método tradicional de obtenção de anticorpos monoclonais em altas concentrações é através de indução de ascite em camundongos. Estatécnica vem sendo substituída por
cultivos de hibridomas em altas concentrações celulares. Neste trabalho, foram cultivados hibridomas secretores de anticorpos monoclonais anti-dengue tipo 2 em frascos T, garrafas rotatórias (roller) e frascos do tipo spinner, utilizando-se o meio DMEM, suplementado com soro fetal bovino a 10%, e o meio comercial livre de soro animal Ex-Cell® TiterHigh TM
(Sigma). Ao longo dos diferentes cultivos, foram avaliadas a concentração celular, viabilidade celular e as concentrações de nutrientes (glicose eglutamina), metabólitos (lactato e amônio) e produto (IgG). A partir dos resultados obtidos, foram calculadas as grandezas representativas do metabolismo celular: concentração máxima de células (X
máx), taxa específica de crescimento celular (µexp), tempo de duplicação (td) e coeficientes de rendimento de glicose em células (YX/glc), glutamina em células (Y
X/gln), células em produto (YP/X),
glutamina em amônio (YNH4/gln), glicose em lactato (Ylac/glc), glicose em produto (YP/glc) e glutamina em produto (YP/gln). O meio livre de soro mostrou ser capaz de fornecer melhores condições para o crescimento celular (alcançando 4 x 106
céls/mL), mantendo a viabilidade por um período maior de tempo, nos três sistemas decultivo testados. Quanto à formação de
produto, no meio livre de soro, os hibridomas também secretaram altas concentrações de IgG, alcançando níveis de 3 µg/mL. Os melhores resultados de crescimento e viabilidade celular
foram observados em garrafas rollera 40 rpm (após adaptação a rotações inferiores) e a
produção de IgG foi maior em garrafas rollera 16 rpm (também após adaptação a rotações inferiores) e em frascos do tipo spinner a 50 rpm (após adaptação a rotações inferiores em garrafas rolleraté 40 rpm). Quando foram comparadas as concentrações de IgG entre os sobrenadantes de cultivo e três amostras de fluido ascítico do mesmo hibridoma, foi observado que o fluido ascítico continha concentrações 10 a 20 vezes maiores que as obtidas nos sobrenadantes de cultivo. Entretanto, como os volumes de sobrenadantes de cultivo são
significativamente maiores do que os de fluido ascítico de camundongos, infere-se que é viável a substituição da produção in vivopela obtenção do anticorpo monoclonal estudado neste trabalho em sistemas agitados, utilizando-se meio livre de soro animal. Contudo, sugere-se a condução de experimentos adicionais para confirmação da total viabilidade da obtenção de anticorpos monoclonais anti-dengue tipo2 in vitroutilizando o processo proposto
no presente trabalho. / Since Köhler and Milstein’s work (1975), hybridoma cells have been cultured to obtain monoclonal antibodies for research, diagnostic and therapeutic purposes. The traditional method to obtain high concentrations (5 to 10 mg/mL) of the monoclonal antibodies is the induction of ascite in mice. This technique is being replaced by high cell density cultivations.
In this work, hybridoma secreting anti-dengue type 2 monoclonal antibodies were cultivated in T flasks, roller bottles and spinner flasks, using DMEM medium supplemented with fetal bovine serum at 10%, and the commercial serum-free medium Ex-Cell® TiterHigh TM (Sigma). Cell concentration, cell viability, as well as concentration of nutrients (glucose and
glutamine), metabolites (lactate and amonium) and product (IgG) were evaluated along culture time in the different media and culture systems. Based on these data, variables that reflect the cell metabolism were calculated: maximum cell concentration (Xmáx), specific cell growth rate (µexp), duplication time (td), as well as the yield coefficients of glucose to cells
(YX/glc), glutamine to cells (YX/gln), cells to product (YP/X), glutamine to ammonium (Y
NH4/gln), glucose to lactate (Ylac/glc), glucose to product (YP/glc) and glutamine to product (YP/gln). Among the culture media, the serum-free medium showed to provide better conditions for cell growth (reaching 4 x 106 cells/mL), keeping high cell viabilities for a longer period, in all
three tested culture systems. Concerning product formation, hybridoma also released high IgG concentrations (3 µg/mL) in the serum-free medium. Among the culture systems, the best results for cell growth and viability were found inroller bottles at 40 rpm (after adaptation under lower rotation rates) and IgG production was higher in roller bottles at 16 rpm (after
adaptation under lower rotation rates) and in spinner flasks at 50 rpm (after adaptation under lower rotation rates in roller bottles, up to 40 rpm). The IgG concentrations ascitic fluid presented concentrations 10 to 20 times higher thanthose obtained in culture supernatants.
However, since the volumes of culture supernatant obtained in relatively simple, small-scale culture systems are significantly higher than thoseof mice ascitic fluids, the replacement of in
vivoproduction for in vitroIgG production in stirred systems, using serum-free media, seems to be feasible. Nevertheless, additional experiments should be carried out to confirm the feasibility of switching the production of anti-dengue type 2 monoclonal antibodies for in vitrosystems, using the process proposed in this work.
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Sperm binding properties to uterine epithelial cells in vitro employing a primary porcine endometrium culture systemBergmann, Annabel Elisabeth 21 May 2015 (has links)
In der Schweinezucht werden konventionell 1-3 x109 Spermien als Frischsamen in einem Volumen von 80-100 ml intrauterin versamt. Im Vergleich zur Rinderbesamung, bei der mitunter 2 x106 Spermien zu Trächtigkeiten führen, sind Ejakulate von Ebern ineffizient. Die einzige Möglichkeit geringe Spermienzahlen erfolgreich zu versamen besteht darin die Spermienablage nahe dem Ort der Befruchtung im distalen Isthmus des Eileiters durchzuführen. Die spezies-spezifische Bindung von Säugerspermien an diverse Oberflächenzellen des weiblichen Traktes, die der Kapazitation und Hyperaktivierung vorangehen, setzt die Erkennung von Kohlenhydraten durch lektin-ähnliche Proteine der Spermienplasmamembran voraus Daher wurde vermutet, dass eine mutmaßliche Bindung porziner Spermien an das Uterusepithel ebenfalls Protein-Kohlenhydrat vermittelt ist. Ziel der vorliegenden Arbeit war die Etablierung eines Zellkulturmodells aus primären Uterusepithelien der Sau (Sus scrofa), um mögliche Gründe für die hohen Spermienzahlen in der Schweinbesamung zu untersuchen und zu identifizieren.
Porzine uterine Epithelien wurden mittels Verdau mit Trypsin/EDTA (1x) gewonnen. Zellen wurden auf Collagen (rat tail, type I) auf Kollagen-beschichteten Deckgläschen aus Glas in 6-Well Kulturschalen ausgesät. Die Anheftung der Zellen an die Kollagen-Matrix wurde nach 12-36 Stunden beobachtet. Erste Kolonien bildeten sich nach fünf bis sieben Tagen und Konfluenz wurde nach zehn bis fünfzehn Tagen erreicht. Der Nachweis der Zellart erfolgte mittels Immunfluoreszenz-Färbung mit einem Epithelien-spezifischen Antikörper (anti-Cytokeratin-19). Eberspermien banden innerhalb weniger Minuten an die UEC und verblieben währenddessen motil. Eine verringerte Spermienbindung wurde sowohl auf Aortenendothelien als auch fötalen Fibroblasten des Schweins beobachtet. Dies weist auf das Vorhandensein spermienspezifischer Liganden auf den UEC hin. Spermien, wie auch UEC wiesen hohe Bindungsintensitäten für Lektine die an Glc-NAc, (WGA) sowie Gal-NAc (sWGA) binden. Die Sättigung von Sialinsäure führte zu einer stark verminderten Spermienbindung auf den UEC. Bei einer Sättigung von Glc-NAC wurde kein Unterschied beobachtet. Dies kennzeichnet Sialinsäure als den vermutlich wichtigsten Kohlenhydratrest in der Spermien-Epithelzellbindung.
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A study of an epithelial-mesenchymal transition-inducing transcriptional factor Snail in prostate cancer using a newly-developed three-dimensional culture model. / CUHK electronic theses & dissertations collectionJanuary 2008 (has links)
In recent years, three dimensional (3D)-culture technique has emerged as a very popular approach to reconstruct tissue architectures and develop experimental models for studying epithelial cancers. However, 3D culture models of prostate epithelial cells to mimic prostate cancer development are relatively rare, making it highly desirable to develop and characterize novel 3D culture models suitable for studying prostate cancer. Recently, epithelial-mesenchymal transition (EMT) has emerged as an important mechanism for cancer cell invasion. The zinc finger transcriptional factor Snail as a key regulator of EMT has been found to contribute to aggressive progression in many types of neoplasms. Even though several studies corroborated that EMT is implicated in prostate cancer, the expression patterns of Snail in normal prostate and prostate cancer, and the functional role of Snail in prostate cancer as well as its relation with EMT are still unknown. Based on this background, my major efforts were to establish a 3D culture model of human prostatic epithelial cells with structural and functional relevance to prostate gland and to employ this model to study the functional role of Snail in the prostate cancer. / When embedded in Matrigel for 3D culture, BPH-1 cells developed into growth-arrested acinar structures with a hollow lumen. Ultrastructural examination of BPH-1 spheroids by electricon microscopy indicated that BPH-1 spheroids displayed a polarized differentiation phenotype. Immunoflurescence analysis of polarized epithelial markers further confirmed that BPH-1 spheroids were polarized. In contrast, tumorigenic BPH-1CAFTD cells exhibited disorganized and continuously proliferating structures in Matrigel, with polarized epithelial markers randomly diffused or completely lost. In addition, BPH-1 CAFTD cells displayed significantly higher invasive capacity in comparison to BPH-1 cells by transwell invasion assay. Moreover, LY294002 treatment of BPH-1CAFTD1 and BPH-1CAFTD3 cells in 3D cultures resulted in impaired cell proliferation as evidenced by reduced colony size and decreased Ki-67 index, and western blot analysis showed that cyclin D1 protein levels were significantly decreased, while p21 protein levels were slightly up-regulated in LY294002-treated 3D cultures. Additionally, LY94002 significantly decreased the invasive capacity of BPH-1CAFTD1 and BPH-1CAFTD3 cells. Interestingly, LY294002 treatment completely reverted the disorganized non-polar 3D structures of BPH-1CAFTD1 cells to well-organized polarized spheroid structures in Matrigel, but failed to restore the polarized differentiation in 3D cultures of BPH-1CAFTD3 cells, which still formed compact aggregates as shown by confocal immunofluorescence analysis. Snail protein was barely detected in the epithelial cells of human benign prostatic tissue but significantly elevated as nuclear protein in primary prostate cancer and bone metastatic specimens by immunohistochemical analysis. Snail transcript levels were weakly expressed in a majority of nonmalignant prostatic epithelial cell lines, while markedly increased in almost all tested cancer cell lines. Snail expression induced a morphological switch to more scattered and spindle-shaped appearance in BPH-1 and BPH-1CAFTD1 cells in 2D culture, and immunofluorescence analysis of several EMT specific markers indicated that Snail-expressing cells underwent EMT. In 3D contexts, Snail-expressing cells developed into more disorganized structures with many cords or protrusions, with a concurrent EMT change as evidenced by reduced E-cadherin and increased vimentin expression. In addition, Snail expression augmented the invasive capacities in both BPH-1 cells and BPH-lCAFTD1 cells, but did not significantly affect the migratory capacities. Snail expression enhanced the MMP2 activity in BPH-1 cells and promoted both MMP-2 and MMP-9 activities in BPH-1CAFTD1 cells. Moreover, Snail expression enhanced anchorage-independent growth capability in BPH-1 cells, but failed to initiate tumor formation in nude-mice. Lastly, Snail expression induced a dramatic increase in FoxC2 and SPARC transcripts but a marked decrease in claudin-1 and p63 transcripts. / Chu, Jianhong. / Adviser: Franky Chan Leung. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3448. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 143-166). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
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