The cellular microenvironment in vivo consists of both mechanical and chemical signals, which drive cell function and fate. These signals include the composition, architecture, and mechanical properties of the extracellular matrix (ECM), signaling molecules secreted by cells into their surroundings, as well as physical interactions between neighboring cells. Cells are able to interact with their surroundings through a number of different mechanisms such as remodeling of the ECM through adhesion, contraction, degradation, and deposition of proteins, as well as the secretion of pro- or anti-inflammatory molecules. In diseased states, where homeostasis has been perturbed, inflammatory signals are secreted which can modify the cellular microenvironment. Diseased states such as cancer and fibrosis are often associated with the excessive production of ECM proteins that subsequently lead to an increase in tissue stiffness and changes to ECM architecture. Such changes to the mechanical properties of the cellular microenvironment affect the cytoskeletal arrangement, migration and adhesion of both the parenchymal cells, as well as immune response cells, which migrate to the sites of injury. Further understanding of the inflammatory responses and their relationships to tissue stiffness and ECM architecture could aid in the development of novel strategies to predict diseases as well as to target and monitor therapies. Since inflammation and mechanical properties of the affected tissue are closely interlinked, obtaining a detailed understanding of the interplay between the properties of the microenvironment and the cells that reside within it will be very beneficial to obtain physiologically relevant information. We have investigated the combinatorial effects of matrix stiffness, and architecture in the presence of co-cultures of cells to determine the overall effect on cellular responses and phenotypes. We have conducted studies on co-cultures of cells in 2D and 3D environments to identify how cellular behavior is affected by dimensionality. / PHD / The cellular microenvironment in vivo consists of both mechanical and chemical signals, which drive cell function and fate. These signals include the composition and organization of the extracellular matrix (ECM), signaling molecules secreted by cells into their surroundings, as well as physical interactions between neighboring cells. Cells are able to interact with their surroundings through reorganization of the ECM and secretion of pro- or anti-inflammatory molecules. In diseased states, inflammatory signals are secreted which can modify the cellular microenvironment. Diseased states such as cancer and fibrosis are often associated with the excessive production of ECM proteins that subsequently lead to an increase in tissue stiffness and changes to ECM architecture. Such changes to the mechanical properties of the cellular microenvironment affect the function and behavior of cells within a given tissue. Further understanding of the inflammatory responses and their relationships to tissue stiffness and ECM architecture could aid in the development of novel strategies to predict diseases as well as to target and monitor therapies. Since inflammation and mechanical properties of the affected tissue are closely interlinked, obtaining a detailed understanding of the interplay between the properties of the microenvironment and the cells that reside within it will be very beneficial to obtain physiologically relevant information. We have investigated the combinatorial effects of matrix stiffness, and architecture in the presence of co-cultures of cells to determine the overall effect on cellular responses and phenotypes. We have conducted studies on co-cultures of cells in 2D and 3D environments to identify how cellular behavior is affected by dimensionality.

Every year there are nearly two million new cases of invasive breast cancer worldwide and over 500,000 deaths, the majority from metastatic sites. While cellular changes during tumorigenesis and progression have been studied, our understanding of extracellular matrix remodeling, at the fiber level, by individual and collective cellular cohorts remains limited. Furthermore, recent studies suggest that there is a correlation between the organization of collagen I fibers perpendicular to the tumor and patient survival. However, the underlying mechanism of this alignment remains unknown. The central hypothesis proposed in this dissertation is that breast cancer tumors reorganize collagen I fibers perpendicular to the tumor surface via integrin β1 and matrix metalloproteinases (MMPs). To investigate this hypothesis, we developed a novel in vitro assay that replicates collagen I fiber alignment previously reported in vivo and a new quantitative collagen I fiber orientation algorithm. Our studies using multicellular aggregates, derived from the triple negative breast cancer cell line MDA-MB-231, embedded into collagen I matrices and confocal reflectance microscopy provide novel insights into how the local microenvironment is affected and into local orientation of the collagen I fibers near the spheroid-collagen I interface. These results agree well with our computational studies. Furthermore, the viability of the algorithm is demonstrated using both in silico and in vitro derived images, and shows that this algorithm is more accurate than similar algorithms previously published. Using the developed in vitro assay and computational algorithm it is also demonstrated that knocking down integrin β1 reduces the amount of collagen I aligned perpendicularly to the tumor surface, while inhibiting MMP activity using the broad spectrum MMP inhibitor GM6001 increases the amount of collagen I aligned perpendicularly to the tumor surface at early time points. The work presented here has implications in three-dimensional multicellular assays, accurate fiber orientation analysis, and understanding the role of integrins in matrix reorganization and cancer cell metastasis. / 2019-08-09T00:00:00Z

Objective: A wide range of cardiac diseases is associated with inflammation. “Inflamed” heart tissue is infiltrated with pro-inflammatory macrophages which extensively secrete matrix metalloproteinase 9 (MMP9), a regulator of extracellular matrix turnover. As MMP9 is released from macrophages in a latent form, it requires activation. The present study addresses the role of cardiomyocytes in the course of this activation process. Methods and results: In mono- and co-cultures of pro-inflammatory rat macrophages (bone marrow-derived and peritoneal) and cardiomyocytes (H9C2 cell line) gelatin zymography demonstrated that activated macrophages robustly secreted latent pro-MMP9, whereas cardiomyocytes could not produce the enzyme. Co-culturing of the two cell species was critical for pro-MMP9 activation and was also accompanied by processing of cardiomyocyte-secreted pro-MMP2. A cascade of pro-MMP9 activation was initiated on macrophage membrane with pro-MMP2 cleavage. Namely, pro-inflammatory macrophages expressed an active membrane type 1 MMP (MT1MMP), which activated pro-MMP2, which in turn converted pro-MMP9. Downregulation of MT1MMP in macrophages by siRNA abolished activation of both pro-MMP2 and pro-MMP9 in co-culture. In addition, both cell species secreted MMP13 as a further pro-MMP9 activator. In co-culture, activation of pro-MMP13 occurred on membranes of macrophages and was enhanced in presence of active MMP2. Using incubations with recombinant MMPs and isolated macrophage membranes, we demonstrated that while both MMP2 and MMP13 individually had the ability to activate pro-MMP9, their combined action provided a synergistic effect. Conclusion: Activation of pro-MMP9 in a co-culture of pro-inflammatory macrophages and cardiomyocytes was the result of a complex interaction of several MMPs on the cell membrane and in the extracellular space. Both cell types contributed critically to pro-MMP9 processing.

Yes / Cardiovascular disease is a leading cause of morbidity and mortality. Smooth muscle cells (SMC) comprising the vascular wall can switch phenotypes from contractile to synthetic, which can promote the development of aberrant remodelling and intimal hyperplasia (IH). MicroRNA‐21 (miR‐21) is a short, non‐coding RNA that has been implicated in cardiovascular diseases including proliferative vascular disease and ischaemic heart disease. However, its involvement in the complex development of atherosclerosis has yet to be ascertained. Smooth muscle cells (SMC) were isolated from human saphenous veins (SV). miR‐21 was over‐expressed and the impact of this on morphology, proliferation, gene and protein expression related to synthetic SMC phenotypes monitored. Over‐expression of miR‐21 increased the spread cell area and proliferative capacity of SV‐SMC and expression of MMP‐1, whilst reducing RECK protein, indicating a switch to the synthetic phenotype. Furthermore, platelet‐derived growth factor BB (PDGF‐BB; a growth factor implicated in vasculoproliferative conditions) was able to induce miR‐21 expression via the PI3K and ERK signalling pathways. This study has revealed a mechanism whereby PDGF‐BB induces expression of miR‐21 in SV‐SMC, subsequently driving conversion to a synthetic SMC phenotype, propagating the development of IH. Thus, these signaling pathways may be attractive therapeutic targets to minimise progression of the disease. / King Saud University; College of Medicine , Riyadh, Saudi Arabia

This Thesis is aimed at evaluating the options of renovation for an existing residential building to make it more energy efficient. The various aspects in the basic structures of residential homes are discussed in order to help the user identify the areas of the house for which renovation is required to improve the energy efficiency of the building. These aspects include doors, roof and wall in addition to various systems of electrical wiring, mechanical systems of ventilation, heating and cooling and plumbing systems for the efficient flow of water throughout the house. The renovation options have been described in detail to provide as many possibilities to the user as possible. The building taken for renovation is a 1953 suburban home which has been awarded the honor of being the first building to be labeled as Zero Energy Home in its vicinity. This has made the home so efficient that its expenditure of energy has become equivalent to its energy generation, therefore, cancelling each other out and creating an estimate of zero energy.

The chromatin structure, consisting of DNA and histones, changes dynamically during the cell cycle and cell differentiation. DNA can only be transcribed and replicated when it is packaged loosely, whereas tight packaging allows for more efficient storage. Chromatin remodelling is therefore one of the tools of gene expression control. The chromatin remodelling factors recognise chromatin with varying specificity and have an effect on the interaction between DNA and the histones. One of these factors is the Smarca5 protein. This study investigates the role of Smarca5; its goal is to create a mouse model with the ability to trigger Smarca5 overproduction in specific tissues. This model will be used to study the effect of a high, unregulated dose of Smarca5 on the physiological function of the protein. Previous studies have shown that non-physiological expression of a chromatin-remodelling factor can lead to malignant transformation. Our model can help to understand this process. Another goal of this study is to investigate some phenotype aspects of the mouse model with conditional deletion of Smarca5 in T and B cells, in particular the effects of this deletion on progenitor cell differentiation. Our results show that Smarca5 has an important role in lymphocyte development, and we have observed that...

As doenças renais crônicas (DRC) evoluem com distúrbios na homeostase do cálcio e do fósforo, diminuição na produção de vitamina D e aumento na secreção de PTH. Osteodistrofia renal (OR) é o termo usado para definir as alterações ósseas dos pacientes com DRC e classifica-se em doença de alta remodelação representada pela osteíte fibrosa (OF) e doença mista (DM); e de baixa remodelação representada pela osteomalácia (OM) e pela doença adinâmica (DOA). Pacientes com DRC apresentam elevada incidência de fraturas e recentemente demonstrou-se que a hiperfosfatemia leva a diminuição do volume ósseo. Estudamos o efeito isolado do fósforo no tecido ósseo de animais com insuficiência renal mantidos com infusão fixa de PTH variando o conteúdo de fósforo na dieta. Cinqüenta e cinco ratos Wistar foram submetidos à paratireoidectomia (PTX) e nefrectomia (Nx) com reposição de PTH em diferentes concentrações ou foram sham operados e recebiam infusão de veículo. Todos os animais receberam a mesma dieta variando apenas a concentração de P (pobre em P (pP): 0,2% e rico em P (rP):1,2%). Dividimos os grupos em: Sham (N=8); Sham-pP (N=8); Sham-rP (N=7); NxPTHn-pP (N=8); NxPTHn-rP (N=8); NxPTHe-pP (N=9); NxPTHe-rP (N=7). Após 2 meses, realizamos análises bioquímicas e histomorfometria do fêmur proximal. Os animais que ingeriram dieta rica em fósforo apresentaram hiperfosfatemia assim como menor valor de cálcio sérico. A reposição de PTH foi efetiva e proporcional às concentrações infundidas. A histomorfometria óssea mostrou que os ratos que ingeriram dieta rica em fósforo independente da uremia tinham diminuição do volume ósseo (BV/TV), e que este efeito foi amenizado pela reposição do PTH em concentrações elevadas. Nossos resultados demonstram que o fósforo é deletério para o tecido ósseo e que na uremia são necessários níveis mais elevados de PTH para manter a integridade óssea. / Chronic kidney disease (CKD) involves disturbances in calcium and phosphorus metabolism, reduced vitamin D production and increased parathormone (PTH) secretion. Renal osteodistrophy (RO) is a term used to define bone disease complications of patients with CKD, and is classified in high turnover disease represented by osteitis fibrosa (OF) and mixed bone disease; and low turnover disease represented by osteomalacia (OM) and adynamic bone disease (ABD). It is already known that patients with CKD have high incidence of bone fractures, and it has been demonstrated that hyperphosphatemia results in to decreased trabecular bone volume (BV/TV). We evaluated the effect of phosphorus (P) in rats? bone tissue submitted to experimental uremia that received continuous infusion of 1-34 rat PTH in physiologic or five times the normal values. Fifty five Wistar rats were submitted to parathyroidectomy (PTX), nephrectomy (Nx) and received PTH in different concentrations or some were PTX and NX controls (Sham) that received only vehicle. Rats received identical diets, excepted for the P content which was different according to the group [Low P (LP): 0,2% and high P (HP): 1,2%]. Groups were divided as follow: Sham (N=8), Sham LP (N=8), Sham-HP (N=7), NxPTHn-LP (N=8), NxPTHn-HP (N=8), NxPTHh-LP (N=9), NxPTHh-HP (N=7). After two months, animals were sacrificed and biochemical and bone histomorphometry were performed. Rats who received high P diet developed hyperphosphatemia and hypocalcemia. PTH replacement was effective and in accordance with infusion concentration. Bone histomorphometric analysis showed that HP rats presented low trabecular bone volume (BV/TV) independently of the uremia. BV/TV decreased slightly in the group where PTH continuous infusion was five times the physiologic values. Our results demonstrated that P has a deleterious action on bone tissue and in uremia it is necessary high levels of PTH to maintain bone integrity.

Lam Hiu Yan, Janice. / "Architecture Department, Chinese University of Hong Kong, Master of Architecture Programme 2010-2011, design report." / Includes bibliographical references.

Tsang Chui Lan, Cara. / "Architecture Department, Chinese University of Hong Kong, Master of Architecture Programme 2006-2007, design report." / Includes bibliographical references (p. 68) / Chapter 1.0 --- Foreword / Chapter 1.0.1 --- Thesis Statement / Chapter 2.0 --- Background Study / Chapter 2.0.1 --- Old Dilapidated Industrial Buildings / Chapter 2.0.2 --- Other Uses in Industrial Buildings / Chapter 2.0.3 --- Exhibition Sites / Chapter 2.0.4 --- Concern of Artist / Chapter 2.0.5 --- Existing Galleries / Chapter 3.0 --- Site Study_ FoTan / Chapter 3.0.1 --- City Level _ FoTan Industrial District / Chapter 3.0.2 --- Building Level _ Wah Luen Industrial Center / Chapter 3.0.3 --- Unit Level _ Interview of Artsit / Chapter 4.0 --- Design / Chapter 4.0.1 --- Material / Chapter 4.0.2 --- City Level / Chapter 4.0.3 --- District Level / Chapter 4.0.4 --- Unit Level / Chapter 4.0.5 --- Details / Chapter 5.0 --- Precedent Study / Chapter 5.0.1 --- Steven Holl's Project / Chapter 5.0.2 --- Intervention / Chapter 5.0.2 --- Details / Chapter 6.0 --- Reading List / Chapter 7.0 --- Final Panels

Fung Chi Keung. / "Architecture Department, Chinese University of Hong Kong, Master of Architecture Programme 2007-2008, design report." / Includes bibliographical references.