Fred E. Deatherage

Bruised Tissue. I. Biochemical Changes Resulting from Blunt Injury.

Summary In experimentally inflicted bruises of cattle, the greatest swelling and fluid volume occurred within 2 days. The maximum biochemical changes in bruised tissue were found on or about the fourth or fifth day: These included a drop in N.P.N. to one-fourth of the control level and a 2-fold increase in the “easily split iron” concentration. Moreover, the 10-fold elevation in red pigment was due to extra-stromal hemoglobin. Bilirubin formation in bruised tissue has been demonstrated conclusively and the probable metabolic derivation of this pigment is discussed. Although healing was evident grossly in 7 days, the biochemical values did not return completely to the control levels until the ninth day.

Bruised Tissue IV. Effect of Streptokinase and Trypsin on Healing.

Summary 1. Rabbits previously bruised healed more rapidly following injections of trypsin and SK-SD than did their untreated counterparts. 2. Injections of enzyme preparations into tissue remote from the bruised areas did not result in accelerated healing. 3. Combination of Vit. C and trypsin was superior to trypsin alone in promoting tissue repair.

What is our Food Made of

The driving force which makes life possible is the sun. By photosynthesis, plants, the autotrophs, grow and start new generations. The heterotrophs, including man, eventually use all of the substance produced by photosynthesis and convert it back to the raw materials of photosynthesis—water, carbon dioxide, nitrogen, etc. By such processes the heterotrophs get their nutrients and energy to complete their life cycles and start new generations. The amount of material produced by biological systems is equal to the amount of such material consumed and decomposed by biological systems. Consequently, there must be systems for building protoplasmic material and systems for breaking it down. Otherwise, the world would have long since been buried in biological or organic waste.1

Some Characteristics of Biological Organisms

Since man and the organisms he consumes are all biological in nature, let us examine some of the simple but basic characteristics of living things. The technologies of agriculture which provide food and the technologies of processing, preservation, and distribution which bring these foods to us depend on these same basic characteristics. Brief reflection on all the different plants, animals, and microorganisms (bacteria, yeasts, and fungi) which are the source of our daily food may be almost overwhelming when we consider the detailed biological complexities of each. (Each group of organisms forms a major branch of the biological sciences.) Also, comprehension of the logistics of getting this varied array of organisms to us each day in usable form may actually inspire a sense of awe. Nevertheless, there are some common denominators almost anyone can understand. Through this volume, these principles may be perceived when we get glimpses of some of the problems involved in the development of ancient civilizations and the modern-day problems of providing food for the world’s starving millions or of providing convenience foods in the supermarket. The reader is urged to try to do just that, for, in doing so, one will also gain a profound measure of understanding of the nature of food itself and how food can be most effectively and efficiently used by all.

The Biology of Some Food Organisms

Man’s ability to feed himself determines his survival. The ability of groups of people to form a viable community depends on their collective ability to provide food for themselves. The growth of civilizations depends primarily on their food supplies. So irrespective of level of social organization, survival of the human race is absolutely dependent on a continuing supply of food organisms. But what organisms? Of all of the hundreds of thousands of species of biological organisms on the earth relatively few are consumed by man and still fewer make up the major portion of his present-day food supply.

The Separation and Utilization of Nutrients from the Multiplicity of Substances Naturally Present in Foods

Man, like every other animal, lives by consuming other organisms. In Chapter 6 it was pointed out that organisms differ from each other in the details of their chemical composition even though there are chemical similarities among all biological organisms. Thus man, like every other animal, must have mechanisms for separating substances which are usable and which he needs from the multiplicity of substances which are useless or perhaps even harmful. This is even more apparent when we reflect on the specialized functions of specific cells, tissues, and organs which make up the whole dynamic organism. In order for nerve cells, muscle cells, secretory cells, etc., to perform their specific tasks, they must depend on other cells, organs, and organ systems to maintain the proper biological (cellular) environment.

Environmental Conditions for Life

Living things, as we know them, do not exist on the sun or the moon, and scientists have not found proof that there are living things on the other planets of the solar system. Many places on the earth itself are inhospitable. What then are the environmental conditions which permit an organism to grow, reproduce, and start another generation?

Food Spoilage and the Requirements for Preservation and Distribution

Food processing in the forms of peeling, milling, mixing, slaughter of animals, cooking, baking, etc., and food preservation in the forms of drying, canning, cooking, freezing, etc., are so much a part of American culture and that of other economically developed areas of the world that few people ask why foods are processed and preserved in a particular manner even though without these devices our society would be doomed. Primitive cultures developed systems of food processing and preservation that, although they may not have been as sophisticated as our own, were equally important. Many of these very old techniques are still practiced. In previous chapters we have alluded to certain aspects of the need for food processing and preservation, and now we shall look into these matters more systematically.

World Population Growth and Future Food Supplies

Food enough—there is no greater problem facing the world today. Food requirements are absolutely related to the number of people living on the earth. And this number is increasing at a rate never before experienced in human history. If the world’s population growth is maintained at its present rate, the number of people who must be fed will quadruple in the average lifetime of the readers of these words. This means that in 70 years four times as much food as is available now will be required to feed the hungry. The enormity of the problem is hard to grasp for most Americans, who, as a nation, have never experienced hunger. Such has been the bounty of U.S. agriculture and the efficiency of the food industry—both fruits of the advent of modern science coupled with good fortune in natural resources. But even in the United States food problems of diverse kinds will continue to get more and more public attention—rising prices; crop failures due to drought, floods, and freezing weather; food shortages, famine, and starvation in various parts of the world; international trading of food on a scale never before seen; food trade and the balance of payments. Such attention is evidence of increasing public awareness of the need for more food—the challenge facing all of us.

Economic and Social Conditions Controlling the Supply and Utilization of Food

Economics, sociological factors, and cultural attitudes of large populations, ethnic or religious groups, and even individuals often greatly affect food supplies and general nutrition and health of people. This is understandable because man is a social animal and lives in a social setting. Societies of men are characterized by division of labor and responsibility, and survival of individuals and of societies as a whole depends on this fact. The more highly developed social and economic systems become, the more interdependent individuals become. The industrial revolution of the past two centuries has led to urbanized societies in which fewer people produce food and more people do other tasks necessary to maintain the population as a whole.