Effect of insulin on ultrastructure and glycogenesis in primary cultures of adult rat hepatocytes

Insulin in the presence of high concentrations of glucose has a beneficial trophic effect on the development of primary cultures of hepatocytes. Compared to the situation observed in hormone-free control cultures, the flattening of the reaggregated hepatocytes is enhanced, and the reconstituted cell trabeculae are enlarged and tend to form a confluent monolayer after 3 days; the survival time is prolonged from 3 to 5 or 6 days. Ultrastructural modifications are also initiated by insulin; numerous glycogen particles appear after 24 h, in between the cisternae of the proliferated smooth endoplasmic reticulum. After 48 h, large amounts of glycogen are stored, and numerous polysomes are present. A small number of cells showed an increased synthesis of lipid droplets in the lumen of the smooth endoplasmic reticulum and form liposomes at the same time. After 72 h, cytolysomes filled with glycogen develop, simulating glycogenosis type II. Simultaneously, microtubules and microfilaments, closely related to numerous polysomes, appear in cytoplasmic extensions constituting undulating membranes. The biochemical data demonstrate that, in the absence of insulin, a high concentration of glucose stimulates glycogenesis and hinders glycogenolysis. This effect of glucose on polysaccharide synthesis is progressively lost. The addition of insulin to the culture induces after 48 and 72 h, a three- to fivefold increase of the glucose incorporation into glycogen, as compared to the controls. The presence of insulin is required to maintain the hepatocyte's capacity to store glycogen. Glycogen synthetase is converted into its active form under the influence of glucose. Insulin increases the rate of activation

An android tablet tool for enterprise architecture modeling in small and medium-sized enterprises

Enterprise architecture (EA) is widely used to improve the alignment of different facets of a company, traditionally focused on business-IT alignment. In recent years, the recognition for the need of EA in small and medium-sized enterprises (SMEs) has risen as a means to manage complexity and change [1]. Due to the specific problems and characteristics of SMEs, a different approach is necessary. CHOOSE was therefore developed by Bernaert et al. [2] as an EA approach focused on and adapted to the characteristics and needs of SMEs. During case studies performed with CHOOSE, the application and implementation of EA in general and the CHOOSE approach in particular, has proven to be a complex and challenging task. This paper describes the development and use of a mobile software tool in support of the CHOOSE approach in order to maximize the rate of adoption. The tool should guide the CEO as enterprise architect throughout the entire EA process and facilitate the implementation, management, and maintenance of the resulting EA model. The generic development decisions make this software tool widely applicable for a multitude of models. Finally, evaluation by means of case studies in two Belgian SMEs is presented

Simplicity is not Simple: How Business Architecture in One of Belgium’s Biggest Companies Can Be Simple and Easy-to-Use

Part 9: Engineering MethodsInternational audienceAs organizations are becoming more complex, Enterprise Architecture (EA) serves as an important means to align the strategy with the operations and to achieve business/IT (i.e., Information Technology) alignment. Although numerous approaches have been designed for large enterprises, little EA research was oriented towards small- and medium-sized enterprises (SMEs). However, both organizational types are fundamentally different and require a tailored approach. Therefore, CHOOSE was designed as an EA approach that is in accordance with the needs of SMEs. By performing a case study in the department of a large enterprise, this paper aims to investigate how CHOOSE can be used outside its original context. More specifically, it will be examined how the metamodel and modeling method could be extended to deliver an overview and valuable insights about a complex business reality. To realize this, potential solutions for the encountered issues are formulated and evaluated by the involved business stakeholders

Evaluating and Improving the Visualisation of CHOOSE, an Enterprise Architecture Approach for SMEs

International audienceEnterprise architecture (EA) serves as a means to improve business-IT and strategy-operations alignment in an organisation. While it is a fairly mature domain in large enterprises, the need for EA in small and medium-sized enterprises (SMEs) has only been recently addressed. As SMEs have different characteristics and cope with specific problems, a different approach is essential to enable a successful adoption of EA. In order to meet these particular requirements of SMEs, the EA approach CHOOSE has been developed. In previous research, emphasis has been put on refining the method and metamodel of CHOOSE and on the development of supporting software tools. However, the visual notation of CHOOSE has not been investigated yet, while the form of representation has a great impact on the cognitive effectiveness of a diagram. This paper assesses the current visualisation of CHOOSE, describes alternatives and conducts an experimental comparison