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Despite their microscopic dimensions, bacteria have a significant impact on all life on earth. They inhabit various habitats as diverse as soil, water, acidic hot springs and Arctic environments. Furthermore, many bacteria live in symbiotic or parasitic relationships with animals and plants. With approximately 1030 bacteria on earth, they form a biomass which exceeds that of all plants and animals [1]. Bacteria recycle nutrients, influence the atmosphere and cause disease. To better understand the biological phenomena underlying the bacterial kingdom, several species or so-called model organisms are being extensively studied, assuming that bacteria share some fundamental mechanisms. On the basis of this assumption, discoveries made in the m..

Oral exposure to metals and metal alloys is frequently associated with local and systemic adverse reactions. The studies presented in this thesis shed a new light on the mechanisms by which dentally applied metals can cause irritation, inflammation or allergy. In addition the question is addressed why some metals, such as nickel, are known as strong sensitizers, while others seldom cause allergy. Overall, this thesis contributes to the understanding why metal-sensitivity occurs so frequently and it helps the researcher, dentist and patient to become more aware of the (potential) health effects of dental alloys. This data might also be useful for dentists to select alloys which have minimal immune stimulatory capacity. In addition, the resul..

Head and neck squamous cell carcinoma [HNSCCs] is the sixth most common cancer worldwide, of which the oral squamous cell carcinoma [OSCC] and oropharyngeal squamous cell carcinoma [OPSCC] are two most common tumors with 300.000 new cases worldwide [1]. The traditional risk factors for developing HNSCC are tobacco and excessive alcohol use, which have a synergistic effect [2]. In the last decades, the causative role of high risk human papillomavirus [HPV] in HNSCCs is widely established, particularly in tumors arising from the oropharyngeal region. HPV-positive OPSCC is considered a distinct molecular entity with a better prognosis compared to its HPV-negative counterpart [3, 4]. Despite improvements in conventional therapy, the five-year s..

Worldwide 2.5 billion people lack access to sanitation. This impacts public health, environment, welfare, and moreover results in a loss of resources. Conventional sanitation systems consume energy, chemicals, land and produce sludge that requires disposal, whereas a range of opportunities exists that enables valorization of resources from our “waste”, such as energy, phosphorus, compost, plastic and paper. Resource recovery may become a driver for economic growth and respond to profound changes of the world’s population impacting food security and availability of finite natural resources. The backlog in sanitation development can partly be attributed to the absence of a functional sanitation planning framework that allows for integration o..

Over the last years, it has become generally accepted that animal data is not sufficient for human risk assessment. The drive to reduce, refine and replace the use of test animals (3Rs), particularly in the area of sensitizer risk assessment, (European Commission -Statute-;European Commission -Bill/Resolution-;Williams et al., 2009), has led to increasing pressure to develop superior alternative in vitro human test models. Our studies emphasize that physiologically relevant and immune competent models are needed which not only are human but which also resemble specific three dimensional (3D) tissues, if we are to identify factors in the tissue microenvironment that regulate immune stimulation which in turn will aid the rational development ..

Healthy eating behaviour in childhood is important for children’s growth and development and might protect against the development of obesity and chronic diseases later in life. The school environment provides an effective setting for teaching children about nutrition and healthy eating behaviour. Therefore, school-based nutrition education programmes have increasingly been used in the past few decades to teach children about nutrition and to provide them with the skills to make healthy food choices. However, evaluating these programmes is complex, and studies have shown varying effects. As the programmes differ in content and delivery, it is hard to identify what intervention components and implementation conditions are most effective. Fur..

'From nutrient to satiety signal' There is a clear need to develop preventive strategies for overweight. Worldwide, in 2014, more than 1.9 billion adults were overweight of which 600 million were obese. Also in the Netherlands this number was strikingly high; in 2014, 43.2% of the adults were overweight, of which 12.3% were obese. The only effective weight loss treatment so far is bariatric surgery. This surgery does not only result in long term weight loss, but also in improved metabolic health. Studies on bariatric surgery have suggested that signals from the small intestine contribute to the beneficial effects of this treatment. However, bariatric surgery is only applied when people are extremely obese (BMI >35 kg/m2). Although it is wel..

This thesis addresses three topics in obesity research: a. alterations in the obese brain and b. insulin resistance and inflammation. The studies described in this thesis are performed in humans with the major aim to translate findings from rodents and explore new pathways that might be targeted for future medical treatment...

We argued that the fetal brain may be particular sensitive to developmental programming since the brain is subject to dramatic developmental processes during the prenatal life period and introduced the developmental origins of behavior, health and disease (DOBHaD) hypothesis. The central aim of this dissertation was to examine the effect of exposure to maternal anxiety during pregnancy on neurocognitive functioning in infants and young children. Because research in the DOBHaD field almost exclusively focused on the effects of negative maternal states and traits we also included a potential positive/protective factor in our study: maternal mindfulness...

In the first part of this thesis we investigated the role of the sympathetic nervous system in human bone metabolism and hematopoiesis and in the second part we investigated the hormonal control of bone and bone marrow. Chapter 1 presents an introduction to human bone metabolism, bone marrow physiology and the sympathetic nervous system...

The term ‘exit strategy’ has been considered from various angles and domains by scholars and practitioners alike (Cardon and DeTienne, 2013; Van Dijk, 2011; Artto, 2008; Artto and Wickstrom, 2005; Rogers and Macias, 2004; Boeker and Karichachil, 2002; Alter et al, 2001; Berenson, 1963). Interestingly, not much has been written about exit in relation to the study of Social Venture Entrepreneurship (Cardon and DeTienne, 2013; Van Dijk, 2011)...

Cardiovascular disease is still the leading cause of death around the globe, despite major advances in prevention and treatment. In particular, coronary artery disease (CAD) has become a disease of men and women of all ethnicities. While historically, CAD was a disease of White men, Westernization of developing parts of the world transformed the Western epidemic into a global one. Especially in Asia with billions of inhabitants, large numbers of CAD deaths are projected. In the East-Asian region an increase in cardiovascular deaths of 20% is expected, contrasting with expected stable numbers in the European region...

This thesis describes non-Hodgkin's lymphoma (NHL) care in the Netherlands, the identification of barriers and facilitators for optimal NHL care and the effect of a tailored strategy on the care delivered to NHL patients. All research is done in context of the PEARL study: imProvement of patiEnts' hospitAl caRe for non-hodgkin's Lymphoma...

Noncommunicable diseases (NCDs), such as cardiovascular diseases, cancers, chronic respiratory diseases and diabetes are increasing around the world and are the biggest cause of death globally. Unhealthy lifestyles, including unhealthy dietary patterns, are among the key risk factors for these NCDs...

When in the age of discovery European sailors set sail for new sea routes and unknown destinations, the perception of the world employed in navigating it was often far from how we understand the world today. Still, navigating was not unsuccessful: centuries of European consensus on the flat nature of the earth did not hinder sailors from roaming -the upper- half of it...