Biofabricação de enxertos porosos de PCL/FastOs™: aplicação óssea

A Engenharia de Tecidos é um domínio multidisciplinar que combina especialistas de múltiplos domínios, no sentido de se desenvolverem substitutos biológicos para a regeneração, reparação ou restauração de funções de órgãos ou tecidos. A estratégia mais comum em engenharia de tecidos consiste na utilização de matrizes de suporte (scaffolds) tridimensionais, biocompatíveis, biodegradáveis e altamente porosos, os quais servem de substrato físico ao processo de adesão, proliferação e diferenciação celular. O objectivo deste trabalho de investigação centrou-se na produção e caracterização de scaffolds de PCL e de PCL com partículas de biovidro, abordando um processo de biofabricação, que teve por base o princípio da extrusão. Utilizou-se para tal um equipamento patenteado pelo Centro para o Desenvolvimento Rápido e Sustentado do Produto (CDRsp) designado Bioextruder. Trata-se de um sistema concebido para a produção de matrizes com ou sem encapsulamento de células, de uma forma automática, flexível e integrada. As estruturas obtidas caracterizaram-se quanto às propriedades térmicas, químicas, morfológicas e mecânicas. Realizaram-se ainda, testes de bioactividade e testes de degradação in vitro. Os resultados obtidos mostram que as condições de processamento não induzem qualquer alteração no que diz respeito às propriedades térmicas e químicas dos materiais, que o aumento do teor de biovidro conduz a uma fragmentação da matriz polimérica num período de tempo mais curto, que os scaffolds obtidos apresentam uma geometria bem definida e uma distribuição de poros uniforme. Demonstra-se assim, que a combinação da matriz polimérica (PCL) com o biovidro, sob a forma de scaffolds é promissora para aplicações em Engenharia de Tecidos e Medicina Regenerativa.

Alkali-free bioactive glasses for bone regeneration

Bioactive glasses and glass-ceramics are a class of third generation biomaterials which elicit a special response on their surface when in contact with biological fluids, leading to strong bonding to living tissues. The purpose of the present study was to develop diopside based alkali-free bioactive glasses in order to achieve good sintering behaviour, high bioactivity, and a dissolution/ degradation rates compatible with the target applications in bone regeneration and tissue engineering. Another aim was to understand the structure-property relationships in the investigated bioactive glasses. In this quest, various glass compositions within the Diopside (CaMgSi2O6) – Fluorapatite (Ca5(PO4)3F) – Tricalcium phosphate (3CaO•P2O5) system have been investigated. All the glasses were prepared by melt-quenching technique and characterized by a wide array of complementary characterization techniques. The glass-ceramics were produced by sintering of glass powders compacts followed by a suitable heat treatment to promote the nucleation and crystallization phenomena. Furthermore, selected parent glass compositions were doped with several functional ions and an attempt to understand their effects on the glass structure, sintering ability and on the in vitro bio-degradation and biomineralization behaviours of the glasses was made. The effects of the same variables on the devitrification (nucleation and crystallization) behaviour of glasses to form bioactive glass-ceramics were also investigated. Some of the glasses exhibited high bio-mineralization rates, expressed by the formation of a surface hydroxyapatite layer within 1–12 h of immersion in a simulated body fluid (SBF) solution. All the glasses showed relatively lower degradation rates in comparison to that of 45S5 Bioglass®. Some of the glasses showed very good in vitro behaviour and the glasses co-doped with zinc and strontium showed an in vitro dose dependent behaviour. The as-designed bioactive glasses and glass–ceramic materials are excellent candidates for applications in bone regeneration and for the fabrication of scaffolds for tissue engineering.

Synthesis and computer-assisted design of mitochondrial electron transport-chain inhibitors as antimalarial agents

Tese de doutoramento, Farmácia (Química Farmacêutica e Terapêutica), Universidade de Lisboa, Faculdade de Farmácia, 2014

Peroxide-based hybrid and prodrug antimalarials to deliver cysteine protease inhibitors into the parasitic food vacuole

Tese de doutoramento, Farmácia (Química Farmacêutica e Terapêutica), Universidade de Lisboa, Faculdade de Farmácia, 2014

Engineering new strategies to improve pharmacokinetics of therapeutic proteins

Tese de doutoramento, Farmácia (Biotecnologia Farmacêutica), Universidade de Lisboa, Faculdade de Farmácia, 2014

Biological membranes : biophysical properties and aquaporin function

Tese de doutoramento, Farmácia (Bioquímica), Universidade de Lisboa, Faculdade de Farmácia, 2014

New synthetic methodologies for the transformation of biomass derived intermediates to valuable molecules

Tese de doutoramento, Farmácia (Química Farmacêutica e Terapêutica), Universidade de Lisboa, Faculdade de Farmácia, 2014

Endothelialization of chitosan porous conduits via immobilization of a recombinant fibronectin fragment (rhFNIII7–10)

The present study aimed to develop a pre-endothelialized chitosan (CH) porous hollowed scaffold for application in spinal cord regenerative therapies. CH conduits with different degrees of acetylation (DA; 4% and 15%) were prepared, characterized (microstructure, porosity and water uptake) and functionalized with a recombinant fragment of human fibronectin (rhFNIII7–10). Immobilized rhFNIII7–10 was characterized in terms of amount (125I-radiolabelling), exposure of cell-binding domains (immunofluorescence) and ability to mediate endothelial cell (EC) adhesion and cytoskeletal rearrangement. Functionalized conduits revealed a linear increase in immobilized rhFNIII7–10 with rhFNIII7–10 concentration, and, for the same concentration, higher amounts of rhFNIII7–10 on DA 4% compared with DA 15%. Moreover, rhFNIII7–10 concentrations as low as 5 and 20 lgml 1 in the coupling reaction were shown to provide DA 4% and 15% scaffolds, respectively, with levels of exposed cell-binding domains exceeding those observed on the control (DA 4% scaffolds incubated in a 20 lgml 1 human fibronectin solution). These grafting conditions proved to be effective in mediating EC adhesion/cytoskeletal organization on CH with DA 4% and 15%, without affecting the endothelial angiogenic potential. rhFNIII7–10 grafting to CH could be a strategy of particular interest in tissue engineering applications requiring the use of endothelialized porous matrices with tunable degradation rates.

Study of glycosidic changes in lung cancer: potential effectors in hematogenous metastasis

RESUMO: O cancro do pulmão (LC), uma das principais causas de mortalidade relacionada com cancro em Portugal, pode levar à formação de metástases hematogénicas. A adesão das células tumorais ao endotélio é considerada um dos passos fundamentais envolvidos na metástase. Em células sanguíneas, esta adesão é mediada por ligandos de E-selectina (E-SL), glicoproteínas ou glicolípidos decorados principalmente com sialyl-Lewis x (sLex) e sialyl-Lewis a (sLea). Tem sido descrito a expressão destes antigénios em LC, contudo o seu papel funcional em permitir a adesão das células de LC ao endotélio é ainda pouco compreendido. Foram analisadas amostras emparelhadas normais e tumorais de pacientes com cancro de pulmão de não-pequenas células (NSCLC) e três linhas celulares de LC. Immunoblotting assays com anti-sLex/sLea e molécula quimérica de E-selectina demonstraram que tecidos tumorais de LC sobreexpressam significativamente E-SL e resultados de citometria de fluxo demonstraram uma expressão elevada de E-SL nas linhas celulares. Para compreender o mecanismo da sobreexpressão de E-SL em tecidos tumorais e linhas celulares de LC, foi analisada a expressão de genes envolvidos na biossíntese de E-SL, nomeadamente FUT3, FUT4, FUT6, FUT7, ST3GAL3, ST3GAL4, ST3GAL6, β4GALT1, GCNT1 e GALNT3. Observou-se a sobreexpressão das fucosiltransferases FUT3, FUT6 e FUT7 em tecidos tumorais de LC e FUT3 em linhas celulares de LC, sendo que neste último, esta expressão é correlacionada com um aumento da adesão das células de LC às selectinas endoteliais. Foi observado que uma baixa expressão de FUT4 em tecidos tumorais está associada com estadios menos avançados de NSCLC. Foram analisadas ainda proteínas decoradas com sLex/sLea, tendo-se identificado como E-SL o antigénio carcinoembrionário em NSCLC. Em resumo, esta tese contribuiu para uma melhor compreensão das alterações glicosídicas e moléculas que podem influenciar a progressão tumoral do LC, podendo permitir identificar futuramente novos biomarcadores de diagnóstico/prognóstico e potenciais alvos terapêuticos para o NSCLC.--------------------------ABSTRACT: Lung cancer (LC), one of the major causes of mortality related to cancer in Portugal, may lead to hematogenous metastasis. Adhesion of cancer cells to endothelium is considered one of the crucial steps involved in metastasis. In blood cells, this adhesion is initiated by endothelial selectin ligands (E-SL) that are glycoproteins or glycolipids decorated mostly with sialyl-Lewis x (sLex) and sialyl-Lewis a (sLea). While LC has been described as expressing these sialyl Lewis antigens, its functional role in allowing LC adhesion to endothelium is still poorly understood. We analyzed paired tumor and normal tissues samples from non-small cell lung cancer (NSCLC) patients and three LC cell lines. Immunoblotting assays with anti-sLex/sLea and E-selectin chimera demonstrated that LC tumor tissues significantly overexpress E-SL and flow cytometry results indicated that E-SL are also abundantly expressed in LC cell lines. To understand the mechanism behind the overexpression of E-SL in LC tissues and cell lines, we analyzed the expression of genes involved in its biosynthesis, namely FUT3, FUT4, FUT6, FUT7, ST3GAL3, ST3GAL4, ST3GAL6, β4GALT1, GCNT1 and GALNT3. It was observed the overexpression of fucosyltransferases FUT3, FUT6 and FUT7 in LC tumor tissues and FUT3 in LC cell lines, being this last one correlated with an increased reactivity of the LC cells to endothelial selectins. It was described that low expression of FUT4 in tumor tissues is correlated with early stages of NSCLC. We also analyzed scaffolds proteins of sLex/sLea and it was identified the carcinoembryonic antigen as an E-SL in NSCLC. In summary, this thesis contributed to a better understanding of the glycosidic changes and molecules that can influence tumor progression of LC, allowing identifying in the future new diagnosis/prognosis biomarkers and potential therapeutic targets for NSCLC.

Elucidating the role of glycans in leucocyte function

RESUMO:O processo de glicosilação é a modificação pós-traducional de proteínas mais comum e está envolvido em vários processos fisiológicos e patológicos. Especificamente, certos perfis glicosídeos estão correlacionados a estados específicos de diferenciação celular, e podem modular vários eventos celulares, como sinalização celular, migração celular e interações hospedeiro-patogénio. Assim sendo, a glicosilação desempenha um papel crucial na modulação de vários processos imunológicos. No entanto, permanece por esclarecer como as estruturas glicosídicas influenciam a imunidade. Especificamente, algumas estruturas glicosídicas terminais que estão modificadas pela ligação de ácido siálico desempenham um papel importante em várias funções do sistema imune, nomeadamente migração leucocitária em contexto de inflamação e ativação de células imunes. Como tal, este trabalho teve como objectivo investigar como a expressão de certos glicanos influencia componentes importantes da resposta imune inata e adaptativa. Este trabalho está dividido em três componentes principais: 1) A imunidade está amplamente dependente da habilidade das células circulantes migrarem para os tecidos inflamados, sendo que a ligação de leucócitos à Eselectina endotelial é o primeiro passo. Assim, nós analisámos a estrutura e função dos ligandos de E-selectina que são expressos pelas células humanas mononucleares de sangue periférico (PBMCs), fornecendo novos conhecimentos para a compreensão dos intervenientes moleculares que mediam a ligação dos monócitos, células CD4+ e CD8+T e células B ao endotélio vascular. Surpreendentemente, os monócitos apresentaram maior capacidade de ligação à E-selectina comparativamente aos linfócitos. Esta observação pode ser explicada pelo facto de os monócitos humanos expressarem, uniformemente, um vasto reportório de glicoproteínas que exibem afinidade de ligação à E-selectina, nomeadamente: as glicoformas do CD43 (CD43E) e do CD44 (HCELL), em adição à já previamente reportada glicoforma da PSGL-1 (CLA). Consistentemente, a diferente capacidade que as diversas populações linfocitárias apresentam de se ligar à E-selectina, está integralmente relacionada com a sua expressão de glicoproteínas com afinidade de ligação à E-selectina. Enquanto que as células CD4+T apresentam uma elevada reatividade à E-selectina, as células CD8+T e B demonstram pouca ou nenhuma capacidade de ligação à E-selectina. Esta atividade de ligação à E-selectina das células CD4+T é conferida pela expressão de HCELL, em adição às já previamente reportadas CLA e CD43E. As células CD8+ T não expressam HCELL e apenas expressam pequenas quantidades de CLA e CD43E, enquanto que as células B não expressam ligandos de Eselectina. Mais, a exofucosilação da superfície destas células, levou ao dramático aumento da expressão dos ligandos de E-selectina em todos as populações leucocitárias, verificando-se que a criação de certos ligandos de E-selectina está dependente do tipo de célula, após fucosilação. Colectivamente, estes resultados redefinem o nosso conhecimento acerca dos mecanismos moleculares que governam o tráfico das células mononucleares de sangue periférico em contexto de inflamação. 2) A habilidade das células dendríticas (DCs) para extravasarem em locais de inflamação é crucial para o sucesso da terapia com DCs. Assim, analisámos a estrutura e função das moléculas de adesão que mediam a migração transendotelial (TEM) das DCs. Para isso, foram usadas DCs geradas a partir da diferenciação de monócitos (mo-DCS), obtidos quer pelo métodos de separação imuno-magnética de células CD14+ (CD14-S) ou por isolamento por aderência ao plástico (PA-S). Os resultados obtidos indicam que as glicoformas de ligação à Eselectina de PSGL-1, CD43 e CD44 são expressas pelas CD14-S mo-DCs, enquanto que as PA-S mo-DCs expressam apenas CLA. É importante notar que a ligação do CD44 nas mo-DCs, mas não nas PA-S mo-DCs, desencadeia a ativação e consequente adesão da VLA-4 ao endotélio na ausência de um gradiente de quimiocinas. Procedeu-se também à análise dos ligandos E-selectina expressos em mo-DCs geradas a partir de monócitos do sangue do cordão umbilical (UCB) e, inesperadamente, as UCB mo-DCs não expressam qualquer glicoproteína com reatividade à E-selectina. Além disso, a exofucosilação das mo- DCs humanas utilizando uma α(1,3)-fucosiltransferase aumenta significativamente a expressão de HCELL e, portanto, estas células apresentam uma capacidade aumentada para se ligarem à E-selectina em condições de fluxo hemodinâmico. Estes resultados destacam o papel do HCELL no desencadeamento do TEM das CD14-S mo-DCs e sugerem que estratégias para potenciar a expressão de HCELL poderão impulsionar o recrutamento de mo-DCs para locais de inflamação. 3) Outro obstáculo para alcançar o sucesso promissor de vacinas baseadas em DCs é o estabelecimento de abordagens eficientes que poderão melhorar o estado de maturação e apresentação antigénica das DCs. Por conseguinte, foram investigadas abordagens alternativas que podem superar este obstáculo. Através da remoção de ácido siálico de superfície celular das DCs, conseguiu-se induzir a maturação de DC humanas e de ratinhos. Notavelmente, tanto as DCs humanas como as de ratinho, ao serem desialiladas mostraram uma capacidade aumentada para induzir a proliferação de células T, para secretar citocinas Th1 e para induzir a morte específica de células tumorais. Em adição, as DCs desialiladas apresentam uma maior capacidade de apresentação cruzada de antigénios tumorais às células T citotóxicas. Colectivamente, o presente estudo oferece uma visão chave para optimizar a capacidade das DCs em induzir respostas imunitárias anti-tumorais, e indica que o tratamento com sialidase é uma nova tecnologia para melhorar a eficácia e aplicabilidade das vacinas baseadas em DCs. Coletivamente, os nossos resultados demostram como a glicosilação e a sua manipulação podem modular a imunidade. Concretamente, através de uma reação de exofucosilação conseguimos aumentar fortemente a capacidade de os leucócitos extravasarem para os tecidos afectados, enquanto que a remoção dos níveis de ácido siálico da superfície celular das DCs, induz potentes respostas anti-tumorais mediadas por células T citotóxicas. ---------------------------- ABSTRACT: Glycosylation is the most widely form of protein post-translational modification and is involved in many physiological and pathological processes. Specifically, certain patterns of glycosylation are associated with determined stages of cell differentiation and can modulate processes like cell-signaling and migration and host-pathogen interactions. As such, glycosylation plays a crucial role in the modulation of several immune events. However, how glycans execute this immune-modulation and, therefore, influence immunity is still poorly unknown. Specifically, some terminal sialic acid-modified determinants are known to be involved in several physiological immune processes, including leukocyte trafficking into sites of inflammation and cell immune activation. Therefore, in this work, we sought to investigate more deeply how the expression of these glycosidic structures affects events form both innate and adaptive immune responses. To this end, we divided our work into three main parts: 1) Immunity critically depends on the ability of sentinel circulating cells to infiltrate injured sites, of which leukocyte binding to endothelial E-selectin is the critical first step. Thus, we first analyzed the structure and function of the E-selectin ligands expressed on native human peripheral blood mononuclear cells (PBMCs), providing novel insights into the molecular effectors governing adhesion of circulating monocytes, and of circulating CD4+T, CD8+T and B cells, to vascular endothelium under hemodynamic shear conditions. Strikingly, monocytes show a higher ability to tether and roll on endothelial cells than lymphocyte subsets. This is due to the fact that human circulating monocytes uniformly display a wide repertoire of E-selectin binding glycoproteins, namely the E-selectin-binding glycoforms of CD43 (CD43E) and CD44 (HCELL), in addition to the previously described E-selectin-binding glycoform of PSGL-1 (CLA). In addition, we also observed a differential ability of the different lymphocyte subsets to bind to Eselectin under hemodynamic shear stress conditions, and these differences were highly correlated with their individual expression of E-selectin binding glycoproteins. While CD4+T cells show a robust E-selectin binding ability, CD8+T and B cells show little to no E-selectin reactivity. CD4+T cell potent Eselectin rolling activity is conferred by HCELL expression, in addition to the previously reported E-selectin-binding glycoproteins CD43E and CLA. CD8+T cells display no HCELL and low amounts of CLA and CD43E, whereas B cells lack E-selectin ligand expression. Moreover, enforced exofucosylation of cell surface of these cells noticeably increases expression of functional E-selectin ligands among all leukocytes subsets, with cell type-dependent specificity in the protein scaffolds that are modified. Taken together, these findings redefine our understanding of the molecular mechanisms governing the trafficking patterns of PBMCs that are relevant in the context of acute or chronic inflammatory conditions. 2) The ability of circulating dendritic cells (DCs) to extravasate at inflammatory sites is critical to the success of DC-based therapies. Therefore, we assessed the structure and function of adhesion molecules mediating the transendothelial migration (TEM) of human monocyte derived-DCs (mo-DCs), obtained either by CD14 positive immune-magnetic selection (CD14-S) or by plastic adherence of blood monocytes (PA-S). We report for the first time that the E-selectin binding glycoforms of PSGL-1, CD43 and CD44 are all expressed on CD14-S mo-DCs, in contrast to PA-S mo-DCs that express only CLA. Importantly, CD44 engagement on CD14-S mo-DCs, but not on PA-S mo-DCs, triggers VLA-4-dependent adhesiveness and programs TEM in absence of chemokine gradient. We also analyzed the E-selectin ligands expressed on mo-DCs generated from umbilical cord blood (UCB) monocytes, and unexpectedly, UCB mo-DCs do not express any glycoprotein with E-selectin reactivity. Furthermore, exoglycosylation of human mo-DCs using an α(1,3)-fucosyltransferase significantly increases expression of HCELL, and therefore exofucosylated mo-DCs exhibit an augmented ability to bind to E-selectin under hemodynamic shear stress conditions. These findings highlight a role for HCELL engagement in priming TEM of CD14-S mo-DCs, and suggest that strategies to enforce HCELL expression could boost mo-DC recruitment to inflammatory sites.3) Another obstacle to achieve the promising success of DC-based vaccines is the establishment of efficient approaches that could successfully enhance maturation and cross-presentation ability of DCs. Therefore, we investigated an alternative approach that can overcome this problem. Through removal of sialic acid content from DC cell surface we are able to elicit maturation of both human and mouse DCs. Notably, desialylated human and murine DCs showed enhanced ability to induce autologous T cell to proliferate, to secrete Th1 cytokines and to kill tumor cells. Moreover, desialylated DCs display enhanced cross-presentation of tumor antigens to cytotoxic CD8+ T cells. Collectively, this study offers key insight to optimize the ability of DCs to boost anti-tumor immune responses, and indicates that the treatment with an exogenous sialidase is a powerful new technology to improve the efficacy and applicability of DC-based vaccines. Overall, our findings show how glycosylation and its manipulation can modulate immunity. Concretely, through an exofucosylation reaction we are able to greatly augment the ability of leukocytes to extravasate into injured tissues, while removal of sialic acid moieties from cell surface of DCs, significantly potentiate their ability to induce anti-tumor cytotoxic T cell-mediate responses.

Extracellular matrix components in peripheral nerve repair: how to affect neural cellular response and nerve regeneration?

Peripheral nerve injury is a serious problem affecting significantly patients' life. Autografts are the "gold standard" used to repair the injury gap, however, only 50% of patients fully recover from the trauma. Artificial conduits are a valid alternative to repairing peripheral nerve. They aim at confining the nerve environment throughout the regeneration process, and providing guidance to axon outgrowth. Biocompatible materials have been carefully designed to reduce inflammation and scar tissue formation, but modifications of the inner lumen are still required in order to optimise the scaffolds. Biomicking the native neural tissue with extracellular matrix fillers or coatings showed great promises in repairing longer gaps and extending cell survival. In addition, extracellular matrix molecules provide a platform to further bind growth factors that can be released in the system over time. Alternatively, conduit fillers can be used for cell transplantation at the injury site, reducing the lag time required for endogenous Schwann cells to proliferate and take part in the regeneration process. This review provides an overview on the importance of extracellular matrix molecules in peripheral nerve repair.

Translation of biomechanical concepts in bone tissue engineering: from animal study to revision knee arthroplasty.

Bone defects in revision knee arthroplasty are often located in load-bearing regions. The goal of this study was to determine whether a physiologic load could be used as an in situ osteogenic signal to the scaffolds filling the bone defects. In order to answer this question, we proposed a novel translation procedure having four steps: (1) determining the mechanical stimulus using finite element method, (2) designing an animal study to measure bone formation spatially and temporally using micro-CT imaging in the scaffold subjected to the estimated mechanical stimulus, (3) identifying bone formation parameters for the loaded and non-loaded cases appearing in a recently developed mathematical model for bone formation in the scaffold and (4) estimating the stiffness and the bone formation in the bone-scaffold construct. With this procedure, we estimated that after 3 years mechanical stimulation increases the bone volume fraction and the stiffness of scaffold by 1.5- and 2.7-fold, respectively, compared to a non-loaded situation.

Gibson Tie

The Brock University tie was cut from a bolt of silk manufactured in Sussex, England. This was the first of 100 Brock ties specially ordered from Swords Custom Furnishings of Toronto. Dr. Gibson received this tie in May of 1967. The tie was eventually presented to Special Collections and Archives in 2002 from the Dr. James A. Gibson fonds.

The effect of pH and ethanol on the astringent sub-qualities of red wine, and the implications for optimum grape maturity /

The first objective of this study was to identify appropriate sensory descriptors to assess the astringent sub-qualities of red wine. The influence of pH and ethanol on the sensation of astringency in red wine was evaluated, using a de-alcoholized red wine. A portion of the wine was adjusted to the pH values of 3.2, 3.4, 3.6 and 3.8, and another portion was adjusted to ethanol concentrations of 0%, 6%, 12%, and 15%. In addition, the pH 3.4 and 3.6 treatments were adjusted to an ethanol concentration of 12% and 15% all wines were then assessed sensorially and seventeen terms were identified, through panel discussion, to describe the mouth-feel and taste qualities: velvet, aggressive, silk/satin, dry, fleshy, unripe, pucker viscosity, abrasive, heat, chewy, acidity, grippy/adhesive, bitter, balance, overall astringency, and mouth-coat. Descriptive analysis profiling techniques were used to train the panel and measure the intensity of these attributes. It was found that decreasing pH values (averaged across all ethanol concentrations) showed an increase in the overall astringency of the wine. The combined treatments of ethanol and pH, real wine parameters (pH 3.4 and 3.6; 12% and 15% ethanol) did not have an effect on the perception of the astringent sub-qualities of the wine. A time intensity study was also included using the pH and ethanol adjusted wines, which showed that as the ethanol level of the wines increased so did the time to maximum intensity. The second objective was to identify appropriate sensory descriptors to evaluate the influence of grape maturity and maceration technique (grape skin contact) on the astringency sub-qualities of red vinifera wines from Niagara. The grapes were harvested across two dates, representing an early harvest and a late harvest. A portion of the Cabernet Sauvignon grapes wine was divided into three maceration treatments of oneweek maceration, standard two-week maceration, three-week maceration, and MCM. Another portion of both the early and late harvest Cabernet Sauvignon grapes were chaptalized to yield a final ethanol concentration of 14.5%. The wines were assessed sensorially and thirteen terms were identified, through panel discussion, to describe the mouth-feel and taste qualities: carbon dioxide, pucker, acidity, silk/chamois, dusty/chalky/powdery, sandpaper, numbing, grippy/adhesive, dry, mouthcoat, bitter, balance and, overall astringency. Descriptive analysis techniques were used to train the panel and measure the intensity of these attributes. The data revealed few significant differences in the mouth-feel of the wines with respect to maturity; which included differences in overall astringency and balance. There were varietal differences between Cabernet Sauvignon, Cabernet Franc, and Pinot Noir and differences for Cabernet Sauvignon wines due to the length and manner of maceration and as a result of chaptalization. Statistical analysis revealed a more complex mouth-feel for the Pinot Noir wines; and an increase in the intensity of the astringent sub-qualities as a result of the addition of sugar to the wines. These findings have implications for how processing decisions, such as optimum grape maturity and vinification methods may affect red wine quality.

Office of the City Clerk, St. Catharines Records, 1928-1974, n.d.

The site of present-day St. Catharines was settled by 3000 United Empire Loyalists at the end of the 18th century. From 1790, the settlement (then known as "The Twelve") grew as an agricultural community. St. Catharines was once referred to Shipman's Corners after Paul Shipman, owner of a tavern that was an important stagecoach transfer point. In 1815, leading businessman William Hamilton Merritt abandoned his wharf at Queenston and set up another at Shipman's Corners. He became involved in the construction and operation of several lumber and gristmills along Twelve Mile Creek. Shipman's Corners soon became the principal milling site of the eastern Niagara Peninsula. At about the same time, Merritt began to develop the salt springs that were discovered along the river which subsequently gave the village a reputation as a health resort. By this time St. Catharines was the official name of the village; the origin of the name remains obscure, but is thought to be named after Catharine Askin Robertson Hamilton, wife of the Hon. Robert Hamilton, a prominent businessman. Merritt devised a canal scheme from Lake Erie to Lake Ontario that would provide a more reliable water supply for the mills while at the same time function as a canal. He formed the Welland Canal Company, and construction took place from 1824 to 1829. The canal and the mills made St. Catharines the most important industrial centre in Niagara. By 1845, St. Catharines was incorporated as a town, with the town limits extending in 1854. Administrative and political functions were added to St. Catharines in 1862 when it became the county seat of Lincoln. In 1871, construction began on the third Welland Canal, which attracted additional population to the town. As a consequence of continual growth, the town limits were again extended. St. Catharines attained city status in 1876 with its larger population and area. Manufacturing became increasingly important in St. Catharines in the early 1900s with the abundance of hydro-electric power, and its location on important land and water routes. The large increase in population after the 1900s was mainly due to the continued industrialization and urbanization of the northern part of the city and the related expansion of business activity. The fourth Welland Canal was opened in 1932 as the third canal could no longer accommodate the larger ships. The post war years and the automobile brought great change to the urban form of St. Catharines. St. Catharines began to spread its boundaries in all directions with land being added five times during the 1950s. The Town of Merritton, Village of Port Dalhousie and Grantham Township were all incorporated as part of St. Catharines in 1961. In 1970 the Province of Ontario implemented a regional approach to deal with such issues as planning, pollution, transportation and services. As a result, Louth Township on the west side of the city was amalgamated, extending the city's boundary to Fifteen Mile Creek. With its current population of 131,989, St. Catharines has become the dominant centre of the Niagara region. Source: City of St. Catharines website http://www.stcatharines.ca/en/governin/HistoryOfTheCity.asp (January 27, 2011)