Art or science

Principles and Techniques of Electron Microscopyby M.A. Hayat, 2000, Cambridge University Press.$55.00 hbk/$20.00 pbk (541 pages)ISBN 0 521 63287 0/0 442 25694 9Contrary to popular belief, the art of electron microscopy (EM) has been quietly replaced over the past 20 years and has been turned into a powerful quantitative and analytical scientific discipline. This quiet revolution in methods of specimen preparation, equipment development and the understanding of high-resolution morphology has resulted in a powerful and objective set of tools ideally suited to molecular cell biologists.In this exciting climate of change, a book introducing both experienced and novice electron microscopists to the new EM technologies should find a large and eager audience. Professor Hayat promises such with this new book, acknowledging the obsolescence of some established procedures and offering a new approach to EM textbooks by presenting practical details as well as covering the theoretical principles of modern approaches to specimen preparation. Unfortunately, this book missed the boat on its aims and might even help relegate EM back onto the walls of art galleries to be the preserve of a few gifted people and not propel it into general use and the frontline scientific journals where it belongs.Why is this so? – especially when Hayat is a respected author of EM textbooks, and this is the fourth edition of a popular EM text. The book is obviously a work of effort and enthusiasm from the hands of an expert. The text includes extremely detailed chapters on colloidal gold, low-temperature methods and applications involving microwave processors. These augment equally detailed chapters covering more classical subjects such as chemical fixation, dehydration and embedding, specimen support films, staining methods and thin sectioning. An additional, and oddly placed, chapter is added to cover the methods involved with preparing and immunolabeling plant tissues for EM.The problems come not from the chapters covering the more traditional or classic subjects, which I found to be extremely useful and learned something every time I looked into them. Instead, they come from the chapters covering the newer specimen-preparation methods. They are written partially in the style of a scientific text, where statements are attributed to specific sources, and partially as a dogmatic teaching text. Despite being a poor choice for a single-author book, both styles fail badly when not carefully proofread for accuracy and for inclusion of specific facts. This is where the book fails to achieve its aims.For a book proposing to offer information to novices, and presumably provide sufficient information to get them started, it is surprising that there is both omission of important information as well as factual inaccuracies. This is unfortunate in a textbook destined for a world market rich with many potential new microscopists.Glaring examples of omission are present throughout. Perhaps the most obvious is that gold quantitation (and related stereology) is not discussed – subjects that deserve a chapter of their own in a book such as this.A more-specific omission can be illustrated by taking an example from the chapter on colloidal gold. There is a micrograph of a thawed cryosection labeled with three different antibodies visualized using gold particles of three different sizes. This micrograph is a good example of multiple labeling on cryosections and is similar to images that appear routinely in the current scientific literature. However, the text surrounding the micrograph does not attempt to explain how this labeling was produced, restricting itself to only describing double labeling of resin sections using methods that cannot work if three antibodies are used. This limited coverage of multiple labeling, in addition to ignoring the many methods available to immunocytochemists, also results in a failure to discuss the problems involved with the few methods described.The approach to low-temperature methods is confusing and inaccurate. Insufficient distinction is made between freezing biological material in a fully hydrated state and freezing fixed and cryoprotected samples. Preparing cryosections for immunocytochemistry is not well explained and neither is freeze substitution. Sometimes the wrong advice is given, which means that the protocol will not work. Both these methods are important tools for microscopists, especially those new to the field who will be looking specifically for explanations of these methods.Microwave technology is relegated to descriptions of effects caused by heating, with no discussion of other effects of microwave energy on the specimen. Much is made of the use of microwaves in antigen retrieval, which is still experimental at the EM level and more dependent on the biological system under study than the specific protocol applied. Yet the rapid resin-embedding methods that use microwave processors to take wet biological material to resin-embedded, ready-to-section blocks in less than four hours are barely mentioned. This innovation is probably one of the more important uses of microwave processors in an EM laboratory today.The perceived loss of specific skills in biological EM throughout the scientific community will mean that many beginners will take the publicity claims of the book to heart and read it. This is where the book will fail in its mission of describing techniques and the underlying principles to the uninitiated. How will these readers avoid wasting time trying out protocols that will not work or looking for equipment that does not exist if there is no expert to help them interpret the book?In my opinion, Hayat should not only rely on his own expertise when writing these books but should also subject his work to the eyes of critical scientific colleagues willing to carefully and ruthlessly read the chapters prior to publication.