Rapid Acceleration of Diagnostics (RADx®) Tech was the key diagnostics component of a three-pronged national strategy, including vaccines and therapeutics, to respond to the COVID-19 pandemic. Unprecedented in the scale of its mission, its budget, its accelerated time frame, the extent of cross-government agency collaboration and information exchange, and the blending of business, academic, and investment best practices, RAD Tech successfully launched dozens of US Food and Drug Administration Emergency Use Authorization diagnostic tests, established a new model for rapidly translating diagnostic tests from the laboratory to the marketplace, and accelerated public acceptance of home-based diagnostic tests. This chapter provides an overview of the processes utilized by RADx Tech during the COVID-19 pandemic to improve clinical laboratory tests and identify, evaluate, support, validate, and commercialize innovative point-of-care and home-based tests that directly detected the presence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus.

Introduction

What does the title of this chapter actually mean? It has to be said at the outset that it sounds more comprehensive than it can possibly be within the constraints of space and the reader's patience. In other words, it has to represent the author's selective interests and prejudices. In this case this will wholly exclude from consideration the role of large arteries and their mechanical properties, apart from one brief mention. Instead the focus will be on the following main questions:

1. • Is there endothelial dysfunction in hypertension?

2. – If so, what is its severity?

3. – How does it occur?

4. – Is it influenced and even corrected by antihypertensive drugs?

5. – Is this clinically important?

6. • What determines peripheral vascular resistance, especially in terms of the structure of the vessels concerned?

As one might expect, these are contentious issues despite, or rather because of, intensive research. The reader, as always, will have to make up his or her own mind and should note that in some cases reviews have been cited in order to keep the number of references within manageable limits.

Endothelial dysfunction in hypertension

Is there endothelial dysfunction in hypertension?

The dynamic nature of the endothelium is now very much a truism, though it would have surprised most vascular biologists 30 or even 20 years ago. Table 12.1 lists some of the vasoconstrictor and vasodilator substances produced by the endothelium. Though this list is likely to grow it is also probable that the most important factors have now been identified.

The science of vascular biology has emerged and expanded rapidly over the past 25 years. Research in this area has increased understanding of a wide range of clinical conditions. This book provides a broad overview of the field for both specialist and newcomer to the field, and concise resource for the non-specialist. The multidisciplinary team of contributors covers topics ranging from normal and pathological aspects of endothelial cell function to the role of the vasculature in pregnancy, hypertension and atherosclerosis.

The authors have been selected for their ability to provide clear explanations of their area, resulting in an easily readable text with carefully produced illustrations. This second edition has allowed for increased clarity in presentation: the book has been divided into three sections, basic science, pathogenic mechanisms, and clinical practice. There is also inclusion of information on new and advancing areas in vascular biology including chapters on nitric oxide, apoptosis, imaging and pregnancy.